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Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

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    A comprehensive assessment of agriculture in lowlands of south Brazil: characterization and comparison of current and alternative concepts
    Theisen, Giovani - \ 2017
    Wageningen University. Promotor(en): N.P.R. Anten, co-promotor(en): L. Bastiaans. - Wageningen : Wageningen University - ISBN 9789463436380 - 234
    cropping systems - farming systems - crop management - lowland areas - wetlands - pampas - brazil - intensification - sustainability - productivity - indicators - soil management - rice - flooded rice - oryza sativa - maize - zea mays - glycine max - cover crops - livestock - rotation - mixed farming - seedbed preparation - farm machinery - teeltsystemen - bedrijfssystemen - gewasteelt - laaglandgebieden - wetlands - pampa's - brazilië - intensivering - duurzaamheid (sustainability) - productiviteit - indicatoren - bodembeheer - rijst - natte rijst - oryza sativa - maïs - zea mays - glycine max - dekgewassen - vee - rotatie - gemengde landbouw - zaaibedbereiding - landbouwwerktuigen

    Agriculture in the lowlands of south Brazil is of strategic importance at the national level, since it supplies around 80% of the rice consumed by the Brazilian population. In Rio Grande do Sul, the southernmost state in Brazil, three million hectares of lowlands are ready for grain-based agriculture. Of this area, about half is fallow, partly used for cattle grazing, and irrigated rice is the predominant crop, cultivated annually on 1.1 million ha. The remaining area is used for soybean and other crops. The predominant cropping system is a combination of irrigated rice and cattle. Over the last decades, rice yields have steadily increased, but this rise in yield level has to a large extent been obtained at the expense of a continuously higher use of external inputs. The recent introduction of soybean in rotation with rice has partially improved the system, but in most areas the situation is becoming incompatible with the modern demands for sustainability. This thesis presents a long-term study (2006-2015) of five cropping systems for lowlands. Next to monocrop rice and two rice-soybean rotations conducted in either conventional or minimum tillage, the experiment contained two novel systems based on large ridges, on which soybean and maize were combined with either cover crops or crop-livestock integration in winter. In these last systems, 8-m-wide ridges were built to avoid flooding, thus allowing for diversification of cash crops and the cultivation of cover crops or pastures in winter time, as well as the use of no-tillage. All systems were evaluated at process-level, including soil preparation, seeding, plant nutrition, pest management, irrigation, harvesting, transport and cattle management, as well as regarding their performance for the different dimensions of sustainability, particularly environment, land productivity, economics, energy-use and labour. Next to system assessment, two additional experiments were conducted for the evaluation of two specific technologies for soil management in these areas. Crop livestock integration on the ridge-based system offered the best balance between food production, environmental impact and economics. This system is well suited to be used in fields that are kept fallow, thereby enlarging the agricultural productivity of the lowlands. The additional experiments revealed that a knife-roller can successfully substitute plough-and-harrow for soil preparation after rice harvest, and that germination of weed seeds can be reduced if crop seeding is conducted at a lower speed or using a no-tillage seeder equipped with an improved cutting mechanism. Overall the results show that by using alternative cropping systems that allow for diversification and new methods of field management it is possible to simultaneously attain a larger agricultural production and improved sustainability in the lowlands.

    Agronomic and socioeconomic sustainability of farming systems : A case in Chencha, South Ethiopia
    Dersseh, Waga Mazengia - \ 2017
    Wageningen University. Promotor(en): P.C.. Struik, co-promotor(en): R.P.O. Schulte; D. Griffin. - Wageningen : Wageningen University - ISBN 9789463436830 - 157
    potatoes - solanum tuberosum - ethiopia - food security - farming systems - mixed farming - sustainability - optimization - efficiency - farm surveys - household surveys - socioeconomics - self sufficiency - profits - training - agronomic characteristics - productivity - soil fertility - rotation - animal feeding - improved varieties - inorganic fertilizers - aardappelen - solanum tuberosum - ethiopië - voedselzekerheid - bedrijfssystemen - gemengde landbouw - duurzaamheid (sustainability) - optimalisatie - efficiëntie - bedrijfsonderzoeken - huishoudonderzoeken - sociale economie - zelfvoorziening - winsten - opleiding - agronomische kenmerken - productiviteit - bodemvruchtbaarheid - rotatie - diervoedering - veredelde rassen - anorganische meststoffen

    Potato has multiple benefits and thus can play a vital role in ensuring food security in Ethiopia. However, for diverse reasons, its productivity is low. The farming systems in Ethiopia in which potato is grown, are predominantly mixed farming systems.

    Most of the research in Ethiopia is focused on crop-specific constraints and thus there is limited research in which the interrelations between crop and livestock management practices are investigated. There is also not enough research focused on combined analysis of soil nutrient and animal feed balances and agronomic and socioeconomic efficiencies at farm level.

    This study assessed production constraints and agronomic and socioeconomic sustainability of the farming systems in South Ethiopia and explored the possible synergetic options to alleviate major constraints. More specifically, the study intended to quantify the variation in input and output among farms, to identify constraints hindering expansion of potato production, to evaluate the sustainability of the farming systems at farm level, to identify constraints of sustainable intensification, and to explore synergetic solutions for the major constraints. Different research approaches were used ranging from lab analysis, household surveys, group discussions, to farm surveys.

    Results showed that constraints related to input and product use in potato production vary across households indicating a need for a pluriform advisory model recognizing (and building upon alleviation of) the diversity of constraints identified in this analysis. The sustainability of the farming system is constrained by low agricultural productivity, low soil fertility, poor labour efficiency and limited economic return associated with improper crop rotation, inappropriate soil fertility management practices, shortage of animal feed, labour- and economically inefficient farm practices and labour shortage. However, there is ample scope to overcome the major constraints and simultaneously to optimize farm management.

    The core messages of the study can be summarized as follows:

    1) the current potato production is characterized by low productivity and economic returns due to various socioeconomic, agronomic and biological factors;

    2) the soil fertility is low and there is uneven distribution of nutrients over plots with relatively high fertility levels in the homestead areas;

    3) the current labour shortage can be attributed to mainly inefficiency of agricultural management practices and labour migration to towns for economic reasons indicating that the farming system is not sustainable in terms of labour;

    4) considering the direct return from animal production, most of the farms had very low gross margin with the current management system and this reduced the overall operating profit of farms. The low return from animal rearing was offset by the relatively high profit from crop production indicating the benefit of mixed farming system in sustaining agricultural production; and

    5) each farm can have a wide range of optimized solutions mainly through introduction of improved technologies and subsequent redesigning of the farm managements.

    In general, the findings of the current study indicate that it is worthwhile to assess the sustainability of agricultural production in different farming systems and agro-ecologies of Ethiopia. In addition, the combined effect of introducing improved agricultural technologies and subsequent reconfiguring the farm management is very crucial to increase and sustain agricultural production.

    Is sustainable development of semi-subsistence mixed crop-livestock systems possible? : an integrated assessment of Machakos, Kenya
    Valdivia, R.O. - \ 2016
    Wageningen University. Promotor(en): Tammo Bult, co-promotor(en): J. Antle; Jetse Stoorvogel. - Wageningen : Wageningen University - ISBN 9789462578272 - 233
    sustainable development - development economics - livestock - cash crops - agriculture - mixed farming - development policy - policy - rural areas - poverty - farming - kenya - east africa - duurzame ontwikkeling - ontwikkelingseconomie - vee - marktgewassen - landbouw - gemengde landbouw - ontwikkelingsbeleid - beleid - platteland - armoede - landbouw bedrijven - kenya - oost-afrika

    Sub-Saharan Africa countries face the challenge of reducing rural poverty and reversing the declining trends of agricultural productivity and the high levels of soil nutrient depletion. Despite of numerous efforts and investments, high levels of poverty and resource degradation persist in African agriculture. The Millennium Development Goals Report (MDGR) states that the majority of people living below the poverty line of $1.25 a day belong to Sub-Saharan Africa (SSA) and South Asia. About two thirds of the global rural population lives in mixed crop-livestock systems (CLS), typical of SSA, where interactions between crops and livestock activities are important for the subsistence of smallholders. CLS are characterized by high degree of biophysical and economic heterogeneity, complex and diversified production system that frequently involves a combination of several subsistence and cash crops and livestock. Increasing crop productivity is clearly a key element to improve living standards and to take these people out of poverty. However, agricultural productivity in most of SSA has been stagnant or increased slowly. In addition, the likely negative impacts of climate change on agriculture have accentuated the vulnerability of smallholders.

    The international research community has once more the eyes on SSA with the recently proposed post-2015 MDGs, the Sustainable Development Goals that emphasize the need to achieve sustainable development globally by 2030 by promoting economic development, environmental sustainability, good governance and social inclusion. Governments and scientists are making considerable efforts to develop strategies that include structural transformations of the different sectors of the economy in search of the recipe to achieve the SDGs. Most of these strategies are based on policy and technology interventions that seek to achieve the “win-win” outcomes and move from the usual “tradeoffs” between poverty-productivity-sustainability to synergies. A key message of this thesis is that achieving the goal of sustainable development in semi-subsistence African agriculture will require better understanding of the poverty-productivity-sustainability puzzle: why high poverty and resource degradation levels persist in African agriculture. I hypothesize that the answer to this puzzle lies, at least in part, in understanding and appropriately analyzing key features of semi-subsistence crop-livestock systems (CLS) typical of Sub-Saharan Africa. The complexity and diversity of CLS often constrain the ability of policy or technology interventions to achieve a “win-win” outcome of simultaneously reducing poverty while increasing productivity sustainably (i.e., avoiding soil nutrient losses).

    This thesis focuses on the Machakos Region in Kenya. Machakos has been the center of many studies looking at soil fertility issues and its implications for poverty and food security, including the well-known study by Tiffen et al. (1994). Recently, the Government of Kenya developed the Kenya Vision 2030, a long-term development strategy designed to guide the country to meet the 2015 MDGs and beyond. The agricultural sector is recognized as one of the economic actors that can lead to reduce poverty if appropriate policies are in place. For the Vision 2030, the key is to improve smallholder productivity and promote non-farm opportunities. The Vision 2030 was used to assess if the implementation of some of the proposed plans and policies can lead to a sustainable agriculture for smallholders in the Machakos region.

    This thesis describes and uses the Tradeoff Analysis Model (TOA), an integrated modeling approach designed to deal with the complexities associated to production systems such as the CLS and at the same time, quantify economic and sustainability indicators for policy tradeoff analysis (e.g., poverty indexes and measures of sustainability). The TOA was linked to Representative Agricultural Pathways and Scenarios to represent different future socio-economic scenarios (based on the Vision 2030) to assess the impacts of policy interventions aimed to move agricultural systems towards meeting sustainable development goals.

    One important finding is that the complex behavior of CLS has important implications for the effectiveness of policy interventions. The Machakos analysis provides important findings regarding the implementation and effectiveness of policy interventions addressing poverty and sustainability in Africa and other parts of the developing world. The analysis shows that policy interventions tend to result in much larger benefits for better-endowed farms, implying that farm heterogeneity results in differential policy impacts and that resilience of agricultural systems is likely to be highly variable and strongly associated with heterogeneity in bio-physical and economic conditions. The results shows that a combination of these interventions and strategies, based on the GoK Vision 2030 and the Machakos County plans, could solve the poverty-productivity-sustainability puzzle in this region. The pathway from tradeoffs to synergies (win-win) seems to be feasible if these interventions and strategies are well implemented, however the analysis also shows that some villages may respond better to these strategies than others. The analysis suggests that these interventions may actually benefit most the areas with better initial endowments of soils and climate.

    The analysis also suggested that prices (e.g., maize price) play a key role in the assessment of policy interventions. There is an increasing recognition that analysis of economic and environmental outcomes of agricultural production systems requires a bottom-up linkage from the farm to market, as well as top-down linkage from market to farm. Hence, a two-way linkage between the TOA model and a partial equilibrium market model (ME) was developed. The TOA model links site-specific bio-physical process models and economic decision models, and aggregate economic and environmental outcomes to a regional scale, but treats prices as exogenous. The resulting TOA-ME allows the effects of site-specific interactions at the farm scale to be aggregated and used to determine market equilibrium. This in turn, can be linked back to the underlying spatial distribution of economic and environmental outcomes at market equilibrium quantities and prices. The results suggest that market equilibrium is likely to be important in the analysis of agricultural systems in developing countries where product and input markets are not well integrated, and therefore, local supply determines local prices (e.g., high transport costs may cause farm-gate prices be set locally) or where market supply schedules are driven not only by prices but also by changes in farm characteristics in response to policy changes, environmental conditions or socio-economic conditions. The results suggest that the market equilibrium price associated to a policy intervention could be substantially different than the prices observed without the market equilibrium analysis, and consequently could play an important role in evaluating the impacts of policy or technology interventions.

    As mentioned above, climate change poses a long-term threat for rural households in vulnerable regions like Sub-Saharan Africa. Policy and technology interventions can have different impacts under climate change conditions. In this thesis the likely economic and environmental impacts of climate change and adaptations on the agricultural production systems of Machakos are analyzed.

    Climate change impact assessment studies have moved towards the use of more integrated approaches and the use of scenarios to deal with the uncertainty of future condition. However, several studies fall short of adequately incorporating adaptation in the analysis, they also fall short of adequately assessing distributional economic and environmental impacts. Similarly, climate change is likely to change patterns of supply and demand of commodities with a consequent change in prices that could play an important role in designing policies at regional, national and international levels. Therefore, a market equilibrium model should also be incorporated in the analysis to assess how markets react to changing prices due to shifts in supply and demand of commodities. The TOA-ME was used to incorporate the elements mentioned above to assess the impacts of climate change. Using data from 5 Global Circulation Models (GCMs) with three emission scenarios (SRES, 2000) to estimate the climate change projections, these projections were used to perturb weather data used by a crop simulation model to estimate the productivity effects of climate change. Land use change and impacts on poverty and nutrient depletion at the market equilibrium were then assessed using the TOA-ME model.

    The simulation was carried out for three scenarios, which are a combination of socio-economic and climate change scenarios: a baseline scenario that represents current socio-economic conditions and climate conditions, a climate change and current socio-economic scenarios (i.e., future climate change with no policy or technology intervention), and a climate change and future socio economic conditions which are a consequence of rural development policies.

    Our findings show that in this particular case, the changes on precipitation, temperature and solar radiation do not show a significant difference among the selected emission scenarios. However, the variability is significant across GCMs. The effects of climate change on crop productivity are negative on average. These results show that policy and technology interventions are needed to reduce this region’s vulnerability. Furthermore, the socio-economic scenarios based on policy and technology interventions presented in the case study would be effective to offset the negative effect of climate change on the sustainability (economical and environmental) of the system across a range of possible climate outcomes represented by different GCMs. Finally, the results show that ignoring market equilibrium analysis can lead to biased results and incorrect information for policy making, in particular for the scenario based on policy and technology interventions.

    One of the major conclusions of the thesis are that policy interventions aimed to deal with poverty and sustainability can have unintended consequences if they are not accompanied by a set of policy strategies and investments. For example, increasing the maize price can result in substitution from subsistence crops to maize, without much increase in nutrient inputs, thus increasing soil nutrient losses. The analysis shows that improving soil nutrient balances by increasing fertilizer and manure use is critically important, but is not enough to move the system to a sustainable path.

    There is no one factor that can reverse the negative nutrient balances and move the system towards sustainability. Rather, a broad-based strategy is required that stimulates rural development, increases farm size to a sustainable level, and also reduces distortions and inefficiencies in input and output markets that tend to discourage the use of sustainable practices. The Machakos case shows that a combination of these interventions and strategies, based on the GoK Vision 2030 and the Machakos County plans, could solve the poverty-productivity-sustainability puzzle in this region.

    Mapping the impact of crossbreeding in smallholder cattle systems in Indonesia
    Tri Satya Mastuti Widi, Tri - \ 2015
    Wageningen University. Promotor(en): Akke van der Zijpp, co-promotor(en): Henk Udo; Kor Oldenbroek. - Wageningen : Wageningen University - ISBN 9789462573246 - 136
    rundvee - rundveeteelt - kleine landbouwbedrijven - kruisingsfokkerij - genetische effecten - milieueffect - gemengde landbouw - bedrijfssystemen - dierlijke productie - indonesië - cattle - cattle farming - small farms - crossbreeding - genetic effects - environmental impact - mixed farming - farming systems - animal production - indonesia

    ABSTRACT

    In response to increasing demand for meat, Indonesia’s government has been implementing crossbreeding with European beef breeds to improve the meat production of local cattle. The main objective of the present study was to evaluate the benefits and consequences of crossbreeding in smallholder cattle farming systems in Madura and Central Java. The study used participatory approaches, observations during cultural events in Madura, and measurements of cattle performances, feeding practices and farm inputs and outputs. In Madura, crossbreeding is not a threat to the two cultural events involving cattle, sonok (cow conformation contest) and karapan (bull racing), nor to the sub-populations of Madura cattle in the specific areas where these events are organised. Farmers outside the sonok and karapan areas, prefer Limousin crossbreds (madrasin) to conventional Madura cattle. The current breeding and conservation approaches do not distinguish between different Madura cattle types and do not consider the specific needs of the farmers in the sonok and karapan areas. In Java, farmers perceive that crossbreeding of Simmental with local Ongole cattle is beneficial for them. Crossbreeding was not accompanied with changes in the cattle farming systems. Crossbred cattle reached a higher body weight and therefore had a higher market price, but they also required more feed. This resulted in comparable Gross Margins for farms with crossbred and Ongole stock. Farmers preferred the crossbreds because of their nice appearance, high growth rate and the higher market price for progeny compared to Ongole. Crossbreeding as a tool of intensification did not reduce the carbon footprint and land use per kilogram liveweight produced. The advantage from the faster growth of crossbreds was counteracted by the higher emissions and land use from feed production for crossbreds. The dualism in crossbreeding is that policy makers promote crossbreeding to meet the increasing demand for beef, whereas farmers are concerned with their livelihoods and the multi-functionality of cattle. Crossbreeding contributes to increased meat production at the national level, however, it has limited possibilities to improve cattle production at farm level. Crossbreeding is also not reducing rural poverty. Participatory approaches should ensure that farmers’ views are considered in national crossbreeding policies and practices. In Madura and Central Java, farmers identified economic benefits, feed availability, cattle management, animal performances, additional functions of cattle, and health and fertility as issues to be considered beforehand in a genetic impact assessment of crossbreeding. Other stakeholders mentioned meat production, environmental quality and diversity in farm animal genetic resources as important issues. Crossbreeding will inevitably continue in Java and Madura. Breeding strategies, have to be adjusted, however, as farmers do not want to upgrade their local cattle to Simmental or Limousin. Viable populations of local cattle are needed to ensure sustainable crossbreeding strategies.

    A methodology to compare specialized and mixed farming systems : case studies, in the Netherlands and France
    Guillaume, D. ; PRI, - \ 2012
    Wageningen : Plant Research International - 129
    bedrijfssystemen - gemengde landbouw - gespecialiseerde landbouw - vergelijkingen - indicatoren - gevalsanalyse - nederland - frankrijk - farming systems - mixed farming - specialized farming - comparisons - indicators - case studies - netherlands - france
    In this thesis, the aim was to create a methodology, composed of a set of economic, social and environmental indicators, in order to compare mixed and specialized farming system and to test the methodology in two case studies in the Netherlands and in France. The analysis relies on two farm typologies based on the concepts of representative and typical farms. Accordingly, the two-scale methodology uses the farm accountancy data network (FADN) to compare farming systems over large areas and agri-environmental data collected on-farm to design innovative farming systems. The results are a first step towards understanding up scaling procedure of innovative mixed farming systems at district level. While the municipality of Winterswijk shows a higher potential to develop between-farm mixing, the Ribéracois however presents better possibilities to develop diversified on-farm mixing. Very heterogeneous areas of Europe render difficult to set up a harmonized methodology. The data heterogeneity of case studies and the importance to make good use of existing information and specificities of each case study prevails on harmonizing the set of indicators. The scientific soundness and efficacy of the methodology is empirically verified but further study is needed to validate all indicators. Additionally, a selection of a primary set of information that is required by all work packages and all case studies is necessary to have a common basis for work.
    Identifying agroecological mixed farming strategies for local conditions in San Antonio de Los Baños, Cuba
    Monzote, F.R.F. ; Bello, R. ; Alvarex, A. ; Hernández, A. ; Lantinga, E.A. ; Keulen, H. van - \ 2012
    International Journal of Agricultural Sustainability 10 (2012)3. - ISSN 1473-5903 - p. 208 - 229.
    bedrijfssystemen - cuba - alternatieve landbouw - gemengde landbouw - agro-ecologie - agrarische bedrijfsvoering - duurzame landbouw - plattelandsontwikkeling - farming systems - cuba - alternative farming - mixed farming - agroecology - farm management - sustainable agriculture - rural development - systems - agriculture - indicators - diversity - impact - asia
    Building on previous research at the experimental and national scales, this study was carried out at the local scale over a four-year period on three farms of reference: one specialized dairy farm ‘Vaquería 10’ (33.7 ha) and two mixed farms, ‘Remedio’ (9.4 ha) and ‘La Sarita’ (47 ha). All three farms are located in the San Antonio de Los Baños municipality, Havana, Cuba. This study illustrates the application of the Ecological Framework for the Assessment of Sustainability (ECOFAS). This methodology consists of a cyclical structure of six steps, aimed at guiding the process of implementing innovative mixed (crop–livestock) farming strategies. Local stakeholders (farmers, researchers, extension officers and representatives of the ministry of agriculture in the municipality) identified alternative strategies for agriculture in the region, based on the critical technological, environmental and socio-economic factors constraining the current performance of farming systems. The results show that implementation of ‘best practice’ mixed farming systems management strategies in the region potentially can lead to a strong positive impact on land productivity, food self-sufficiency as well as improve socio-economic performance.
    Agro-landerij: een moderne, regionale samenwerking
    Prins, A.M. ; Galema, P. ; Beldman, A.C.G. ; Laverman, W. - \ 2011
    Wageningen : Wageningen UR
    agrarische bedrijfsvoering - akkerbouw - veehouderij - gemengde landbouw - innovaties - ondernemerschap - drenthe - farm management - arable farming - livestock farming - mixed farming - innovations - entrepreneurship - drenthe
    Het project regionaal gemengd bedrijf Zuidoost Drenthe is gericht op het maken van een businessplan voor een vergaande samenwerking tussen akkerbouwers en veehouders in zuidoost Drenthe, gebaseerd op specialisatie in de bedrijfsvoering. Het uiteindelijk doel is het opzetten van het Nieuw Gemengd Bedrijf, waarin (lokale) ondernemers – die in verschillende takken van sport opereren – en bewoners van het gebied samenwerken. Kortom, samenwerkingsvormen op het gebied van voer, energie, mest en recreatie (beleving). Nieuwe vormen van landbouw vragen om innovatie, samenwerken en risicospreiding, om mee te kunnen gaan in de tijd en klaar te zijn voor de toekomst. De economische structuren vragen erom en de landbouw is in zuidoost Drenthe een belangrijke drager van de economie.
    Five centuries of farming : a short history of Dutch agriculture 1500-2000
    Bieleman, J. - \ 2010
    Wageningen : Wageningen Academic Publishers (Mansholt publication series vol. 8) - ISBN 9789086861330 - 367
    geschiedenis - landbouw - tuinbouw - akkerbouw - veehouderij - gemengde landbouw - zandgronden - landbouwindustrie - nederland - agrarische geschiedenis - history - agriculture - horticulture - arable farming - livestock farming - mixed farming - sandy soils - agribusiness - netherlands - agricultural history
    Where the lower reaches of the rivers Rijn, Maas and Schelde have passed through the Northwest-European plain to finally flow out into the North Sea, a unique country of towns had come about during the Late Middle Ages. Since then, due to its natural and central location, this country, the Netherlands, has turned into a true crossroads of European trade connections between east and west, north and south. A highly urbanised country emerged and as the urban economies prospered they have had a great impact on the surrounding countryside. This in turn has affected the rural communities and has stimulated all kinds of agrarian activities. Highly productive agribusiness complexes have been the result. Today experts rank Dutch agriculture and horticulture as one of the most productive in the world. Milk production per cow and arable farming and horticulture, productivity per man-hour is amongst the highest known. This book is meant to give an overview of the historical processes of five centuries of farming and it makes clear that the old farming society was only seemingly static. This account of Dutch agricultural history demonstrates how Dutch farmers and horticulturist have always been keen on resetting their aims when the ever changing economic environment induced them to do so.
    Decision-making for heterogeneity : diversity in resources, farmers' objectives and livelihood strategies in northern Nigeria
    Berkhout, E.D. - \ 2009
    Wageningen : Wageningen UR (Tropical resource management papers 94) - ISBN 9789085856702 - 231
    besluitvorming - natuurlijke hulpbronnen - boeren - bodemvruchtbaarheid - teeltsystemen - gemengde landbouw - rotatie - braaksystemen - landbouwhuishoudens - doelstellingen - bedrijfssystemen - west-afrika - nigeria - ontwikkelingseconomie - strategieën voor levensonderhoud - modelleren - decision making - natural resources - farmers - soil fertility - cropping systems - mixed farming - rotation - fallow systems - agricultural households - objectives - farming systems - west africa - nigeria - development economics - livelihood strategies - modeling
    Decision-making for heterogeneity : diversity in resources, farmers' objectives and livelihood strategies in northern Nigeria
    Berkhout, E.D. - \ 2009
    Wageningen University. Promotor(en): Arie Kuyvenhoven; Herman van Keulen, co-promotor(en): Rob Schipper. - Wageningen : Wageningen University - ISBN 9789085855224 - 231
    besluitvorming - natuurlijke hulpbronnen - boeren - bodemvruchtbaarheid - teeltsystemen - gemengde landbouw - rotatie - braaksystemen - landbouwhuishoudens - doelstellingen - bedrijfssystemen - west-afrika - nigeria - ontwikkelingseconomie - strategieën voor levensonderhoud - modelleren - decision making - natural resources - farmers - soil fertility - cropping systems - mixed farming - rotation - fallow systems - agricultural households - objectives - farming systems - west africa - nigeria - development economics - livelihood strategies - modeling
    As a result of increasing population pressure, the average farm sizes in the savannah
    regions of West Africa have reduced. By consequence, farmers can no longer rely on
    fallowing to maintain soil fertility. For long farmers have therefore resorted to other
    methods. The most common on-farm strategies to cope with reduced fallow lengths
    are rotation of cereals with nitrogen fixing legumes and crop-livestock integration.
    The most important component of crop-livestock integration is the feeding of crop
    residues to livestock and the subsequent use of manure as fertilizer. At the same time,
    many farmers can no longer rely on farming as their sole source of income and
    diversify into off-farm income sources such as petty trading; local manufacturing
    jobs; or migrate (seasonally) to large urban areas. Hence, the coping strategies in the
    wake of increased population pressure are manifold, and the rural population is far
    from homogenous.
    The aim of this study is to examine in detail three types of heterogeneity and
    their relationships with agricultural production. These three types of heterogeneity
    are: (1) heterogeneity in farmer goals and objectives, (2) heterogeneity in (on-farm)
    soil fertility resources, and (3) heterogeneity in crop-livestock integration. We thereby
    explore how differences in household characteristics and farming strategies relate to
    the three types of heterogeneity distinguished, and how this affects soil fertility levels.
    These types of heterogeneity affect production (decisions) and farmer soil
    fertility resources in different ways. First, developed with the purpose of analysing the
    ex ante impact of policies and technologies on farmers’ soil nutrient use, bioeconomic
    models frequently assume that farmers are homogenous in goals and
    preferences, i.e., their underlying utility function. Similarly, many studies on
    smallholder productivity and efficiency only include observable household
    characteristics and thereby implicitly assume that the relationship between household
    characteristics and farmer goals and objectives is homogenous. In neither type of study there is a clear reason to assume that such behavioural homogeneity holds.
    More importantly, ignoring farmer specific goals and objectives may lead to incorrect
    simulation outcomes from a bio-economic model, as well as biased estimates of efficiency or productivity. In both cases this could lead to ill-formulated policy
    recommendations. This is further investigated in this study.
    Second, most studies focusing on productivity and efficiency in agricultural
    production assume farm size to be homogenous with respect to its soil composition,
    an assumption refuted by numerous field studies. Again, ignoring such information
    may lead to biased estimates and policy recommendations.
    Third, livestock clearly plays an important role for production of manure, but
    manure production is not the main reason for households to keep livestock. Next to
    meat and other tangible benefits contributing to farm incomes in kind or in cash,
    several other non-tangible benefits, such as insurance and storing finances, play a role.
    The importance of these non-tangible preferences for keeping livestock may differ
    from one household to the other, giving rise to differences in the degree to which a
    farmer integrates crops and livestock.
    These types of heterogeneity are further analysed in Chapters 2 till 5 of this
    study. Thereby use is made from various data sources from northern Nigeria. The data
    used includes farmers from villages in different agro-ecological zones in northern
    Nigeria, as well as villages characterized by different levels of market access. The
    villages also differ in population density, but levels of agricultural intensification are
    high throughout the region of study, with fallowing non-existent in nearly all
    locations.
    The description of heterogeneity in farmer goals and objectives, and their effect on
    smallholder efficiency and on soil nutrient budgets is the subject of Chapters 2 and 3
    respectively. Chapter 2 follows an explorative approach in documenting the various
    farmer goals and objectives. While arguable risk aversion and profit maximization are
    important attributes in farmer decision-making, other preferences and attributes may equally play a role. To capture such additional variables, a fuzzy pair-waise goal
    ranking is combined with a set of Likert scale questions. Principal component analysis
    is used to reduce these data into behavioural factors, i.e., the minimum set of
    underlying behavioural latent variables. We subsequently estimate technical and
    allocative efficiency levels by using Data Envelopment Analysis and analyse how
    these are related to farm characteristics and the identified behavioural factors. The
    models in which both intended behaviour and farmer characteristics are included give
    a significantly better fit over models in which only household characteristics are included. More importantly, next to expected effects of risk aversion, two other
    behavioural variables are identified that influence efficiency levels. These variables
    reflect the desire to be a successful farmer and the desire to fulfil subsistence demands
    from own production. On the other hand, the overall effects of these behavioural
    variables are small in relation to other observable household characteristics, and
    additional research should focus if and how agricultural policies should account for
    this heterogeneity.
    In Chapter 3, the relationship between differences in goals and objectives and
    on-farm soil nutrient budgets is explored in more detail, by using a combination of
    multi-objective programming, multi-attribute utility theory and bio-economic
    modelling. The first part of the analysis establishes trade-off curves between the most
    common production attributes included in smallholder studies, i.e., optimisation of
    gross margins, labour use, risk levels and sustainable use of soil resources. The
    estimated trade-off curves reveal that farm plans aimed at optimising gross margins
    and, arguably, sustainable use of soil resources are more favourable, considering the
    nutrient balances, than those aimed at minimising production risks. In the second part
    of the analysis, by using multi-attribute utility theory, farmer specific weights for each
    of these attributes are identified. Risk aversion, operationalised through variance
    minimization, appears an important attribute in this study for many farm households
    with smaller land holdings. Subsistence production of cereals is dominant in such
    farm plans that lead to negative soil nutrient balances, especially for potassium.
    Farmers who place a large importance on gross margins in their utility function are
    likely to benefit most from policies aimed at enhancing profitability through
    improving the functioning of markets. The large group of risk averse farmers will
    have the largest immediate gain in utility from policies and technologies aimed at
    lowering production risk in high-value crops. Additional policies aimed at creating a stronger market–oriented production by the least-endowed farm households could
    play a role in reducing intensity of soil fertility mining. Then, the efficient cropping
    pattern shifts (partially) from cereal cropping to high value crops, associated with
    higher input use.
    In Chapter 4 it is analysed how heterogeneity in soil fertility resources at farm level
    affects maize and sorghum production, and measures of technical efficiency for these
    crops. While arguably crop production is dependent on natural soil fertility levels, this is not always taken into consideration in production function estimations. Two
    variables that can easily be derived from household production surveys are introduced
    as proxies for on-farm heterogeneity in soil fertility. Next to these proxies, detailed
    soil fertility data at village level is included to account for differences in soil fertility
    levels between villages. The results show that the used soil fertility variables have
    significant effects on production, although not always of the expected sign. Secondly,
    the inclusion or omission of such soil fertility variables plays a critical role in testing
    for the presence of inefficiency. In the case of maize production, inefficiency is no
    longer observed after inclusion of the soil fertility variables. Finally, variation in
    labour availability is an important determinant of the inefficiency found in sorghum
    production. The findings highlight the need to further develop and include proxies for
    on-farm soil fertility heterogeneity in smallholder efficiency and productivity studies.
    In Chapter 5 it is investigated how preferences in non-tangible benefits of keeping
    livestock relate to differences in herd size and crop choice at different types of farms.
    Integrating crops and livestock is widely advocated as a method to maintain soil
    fertility levels through increased use of manure. On the other hand, there are many
    other benefits of keeping livestock, such as insurance and storage of finances, in
    addition to manure production. The role of such non-tangible benefits could differ
    across farms, thereby driving apparent differences in observed levels of crop-livestock
    integration. First, a bio-economic simulation model is used to identify, at different
    farm types, the relationships between preferences for non-tangible benefits, optimal
    herd size and crop choice. The simulation outcomes show that optimal herd size
    increases for non-tangible benefits, though herd size decreases again for increased
    importance of tangible benefits, i.e., liveweight production. Furthermore, the results
    from the model suggest that for increasing labour supply, herd size decreases due to a
    shift into vegetable cultivation and consequent reduction of on-farm fodder supply.
    Second, a novel method to measure non-tangible benefits empirically is
    introduced in this chapter. This measurement is done by calculating the difference
    between simulated herd size at maintenance levels, given on-farm fodder supply, and
    actual herd size observations. A regression analysis shows that farm households wellendowed
    with farm and labour are more likely to maintain (too) large herds, possibly
    as a mechanism to store finances. Consequently, these farmers also use more manure.
    It shows that herd size increases demand for fodder products, while there is additional
    evidence that manure use benefits cereal production, but does not benefit other crops.
    Hence, similar to the results in Chapter 3, these results suggest that specific policies
    and technologies are needed to enhance use of manure at the least-endowed farm
    households.
    Finally, in Chapter 6 the wider implications of the research findings and the methods
    used are discussed. More specifically, three topics are discussed in more detail. First,
    it is discussed how research should further address heterogeneity in goals and
    objectives in various types of study. It is thereby argued that experimental field
    research methods could potentially further improve the accuracy of latent variables,
    including the newly identified ones in Chapter 2. Furthermore, such variables could
    further shed new light in other agricultural or development studies at smallholder
    level, such as (dis-)adoption studies. Second, it is discussed how simulation models
    can be improved for more accurate design of policies to promote growth at
    smallholder levels. Both the inclusion of heterogeneity in farmer goals and objectives,
    as done in this study, and the use of robust optimisation methods to account for data
    uncertainty thereby play an important role.
    Finally, the implications of this research for the enhancement of sustainable
    use of soil resources in the savannah regions in Nigeria, and Africa in general, are
    discussed. Most importantly, the results in Chapter 3 and 5 suggest that mostly wellendowed
    farmers tap into markets for high-value crops, and thereby use more organic
    and inorganic inputs. Hence, research should focus on how production, and
    sustainable use of soil resources, at the least-endowed farmers can be enhanced
    further. This can be partially achieved by developing technologies that reduce the risk
    in the cultivation of high-value crops and policies aimed at bringing the leastendowed
    to the market. Potentially this can be achieved through cooperative
    agreements between farmers, but little is yet known if and how such agreements can
    play a role. This can be further investigated by combining bio-economic simulation models and methods from cooperative game theory.
    Scherp blijven door samenwerking
    Animal Sciences Group (ASG), - \ 2008
    S.l. : Bioveem
    samenwerking - agrarische bedrijfsvoering - biologische landbouw - gemengde landbouw - melkveehouderij - akkerbouw - cooperation - farm management - organic farming - mixed farming - dairy farming - arable farming
    Pieter Boons uit Waspik is een echte allrounder in zijn vak. Hij vindt de gemengde bedrijfsvoering het mooiste wat er is. Om die reden kan Pieter veel kwijt in de biologische landbouw. Hij geniet net zoveel van zijn koeien in de melkput, als van het ploegen van een perceel. Wat boeren ook zo prettig maakt voor Pieter, is het samenwerken met andere mensen. Er lopen altijd wel mensen rond op het bedrijf.
    Boeren in Nederland. Geschiedenis van de landbouw 1500-2000
    Bieleman, J. - \ 2008
    Amsterdam : Boom - ISBN 9789085065401 - 671
    landbouw - tuinbouw - akkerbouw - landbouw bedrijven - gemengde landbouw - zandgronden - lössgronden - melkveebedrijven - platteland - urbanisatie - welvaartseconomie - nederland - geschiedenis - landbouw als bedrijfstak - welvaartsstaat - agrarische geschiedenis - agriculture - horticulture - arable farming - farming - mixed farming - sandy soils - loess soils - dairy farms - rural areas - urbanization - welfare economics - netherlands - history - agriculture as branch of economy - welfare state - agricultural history
    In Boeren in Nederland beschrijft landbouwhistoricus Jan Bieleman hoe een land van steden en industrieën toch bij uitstek een landbouwnatie is gebleven. Bieleman legt een glashelder verband tussen de verstedelijking, de groeiende welvaart en de landbouw, die daar telkens weer adequaat op wist in te spelen. Boeren in Nederland. De geschiedenis van de landbouw 1500-2000 is een sterk uitgebreide en geactualiseerde bewerking van Bielemans Geschiedenis van de landbouw in Nederland 1500-1950, dat sinds zijn verschijnen een standaardwerk is
    Farming like we're here to stay : the mixed farming alternative for Cuba
    Funes Monzote, F.R. - \ 2008
    Wageningen University. Promotor(en): Herman van Keulen, co-promotor(en): Egbert Lantinga. - [S.l.] : S.n. - ISBN 9789085049791 - 211
    gemengde landbouw - meervoudig landgebruik - bedrijfssystemen - biodiversiteit - gebruiksefficiëntie - duurzaamheid (sustainability) - ontwikkeling - melkveehouderij - cuba - agro-ecologie - agro-ecosystemen - mixed farming - multiple land use - farming systems - biodiversity - use efficiency - sustainability - development - dairy farming - cuba - agroecology - agroecosystems
    Keywords: Crop-livestock, agro-diversity, mixed farming, dairy production, agro-ecological indicators, sustainability, energy efficiency, local development, Cuba

    Specialization, as opposed to diversification, and export orientation have been historically the basis for patterns of dependence on external inputs and centralized decision-making in the Cuban agricultural model. Low autonomy in farmers’ decision-making (centrally-planned collective farms), scarcity of production inputs and extensive areas of abandoned land on the one hand, and increasing food imports on the other, are threatening sustainable development in the country. However, small farmers and an emergent sector of land tenants under a usufruct system are showing that food for the Cuban population can be produced efficiently and sustainably at home. These small-scale producers, cultivating about 25% of the available agricultural land, generate more than 65% of domestic food production, putting increasing pressure on the collective sector.
    Over the last 15 years, agro-biodiversity and food self-sufficiency have been officially recognized as drivers for increasing productivity and autonomy in decision making. The economic crisis that started in 1990 in Cuba had a strong negative impact on agriculture, but at the same time created conditions for emergence of a new model strongly based on principles of organic agriculture and agro-ecology. Various alternative systems, aimed at sustainable development, were developed during that period, but most of these lacked an integrative perspective on farming system development and followed an input substitution scheme in which high-input industrial practices were substituted by low input agro-ecological ones. Conversion from specialized (monoculture) farming systems into mixed (diversified) farming systems is considered by that model to be an effective step towards implementation of sustainable practices in agriculture. Thus, the current research is aimed at filling some of the conceptual, practical and methodological gaps that constrain a comprehensive transition from specialized dairy farming systems to mixed crop-livestock systems at farm and regional levels. For that purpose a methodological framework was tested for evaluating, monitoring, comparing, analysing and designing land use management strategies for the conversion of specialized dairy farming systems into mixed crop-livestock farming systems.
    Our results show that in comparing different systems, the issue is not simply one of high or low input, specialization or diversification, but that farming system-specific characteristics and the way in which inputs and agro-diversity are interrelated and managed also are at stake. We found that even in low external input agriculture, when comparing specialized and mixed farming systems, the latter achieved higher levels of food production and higher energy and protein production, as a result of more efficient use of natural resources available on farm (or locally). The unique position of the Cuban agricultural sector, both nationally and internationally, provides a context in which these results are highly relevant. High oil prices, climate change and high prices for food in the international markets, combined with national awareness of the necessity to substitute food imports for nationally grown food, as well as a recent government decision to make all unproductive land available for cultivation, open a wide spectrum of possibilities for adoption of alternative technologies. Diversification, decentralization, and movement towards food self-sufficiency are major trends in Cuban agriculture. However, these trends must be translated into systematic and consistent policies to ensure reliable and sustainable production, as well as agriculture’s contribution to a viable economy. Therefore, changes in Cuban agriculture should be driven by conscientious and scientifically-based policies.


    De bijdrage van visvijvers aan de nutriënthuishouding op gemengde kleinschalige landbouwbedrijven
    Verdegem, M.C.J. ; Muendo, P.N. - \ 2007
    Aquacultuur 22 (2007)1. - ISSN 1382-2764 - p. 26 - 32.
    agrarische bedrijfsvoering - gemengde landbouw - voedingsstoffenbalans - visvijvers - visteelt - voedingsstoffenbeschikbaarheid - experimenteel veldonderzoek - toegepast onderzoek - farm management - mixed farming - nutrient balance - fish ponds - fish culture - nutrient availability - field experimentation - applied research
    Vijvers kunnen een aanzienlijke bijdrage leveren aan de nutriëntenkringloop op gemenge landbouwbedrijven. Het integreren van water- en landgebonden productie in gemengde bedrijven kan leiden tot een verhoogde efficiëntie van het nutriëntengebruik. Bij evaluatie van de visteelt wordt vaak alleen gekeken naar de oogst zonder aandacht voor andere voordelen van visteelt zoals waterbeschikbaarheid of efficiëntie van nutriëntengebruik. Bovendien verkiezen boeren vaak geformuleerde voeders, hoewel het voordeel voor de oogst hiervan niet evident is in de gemiddelde eenvoudige onbeluchte vijvers. Een onderzoeksproject is gestart om mogelijkheden voor verbetering in kaart te brengen
    Gecombineerde bedrijven: inkomen stabieler, wel lager
    Jager, J.H. ; Everdingen, W.H. van - \ 2006
    Agri-monitor 2006 (2006)mei. - ISSN 1383-6455 - 2
    gemengde landbouw - inkomsten uit het landbouwbedrijf - agrarische economie - mixed farming - farm income - agricultural economics
    Gecombineerde bedrijven krijgen bij beschrijvingen van de inkomensontwikkeling vaak minder aandacht dan gespecialiseerde bedrijven. Terwijl het inkomen op gespecialiseerde bedrijven van jaar tot jaar sterk kan fluctueren, blijft het op gecombineerde bedrijven vanwege de risicospreiding vrij stabiel. Gemiddeld is het inkomen wel iets lager dan op gespecialiseerde bedrijven.
    Ecolana: Gemengd bedrijf nieuwe stijl, samenwerken veehouders en akkerbouwers: “Voor een landbouw met toekomst in Nederland”
    Animal Sciences Group (ASG), - \ 2006
    Animal Sciences Group
    gemengde landbouw - agrarische bedrijfsvoering - dierhouderij - akkerbouw - duurzame landbouw - mixed farming - farm management - animal husbandry - arable farming - sustainable agriculture
    Brochure met informatie over EcoLaNa, een nieuwe vorm van samenwerken van boeren met een gemengd bedrijf
    Dynamics of livestock development in Gujarat, India: experiences of an Indian NGO
    Patil, B.R. - \ 2006
    Wageningen University. Promotor(en): Herman van Keulen, co-promotor(en): Henk Udo; J.B. Schiere. - [S.l.] : S.n. - ISBN 9789085045304 - 158
    veehouderij - india - melkveehouderij - gemengde landbouw - landbouwkundig onderzoek - landbouwontwikkeling - experimenteel veldonderzoek - kruisingsfokkerij - voedering - diervoedering - modellen - bedrijfssystemenonderzoek - livestock farming - india - dairy farming - mixed farming - agricultural research - agricultural development - field experimentation - crossbreeding - feeding - animal feeding - models - farming systems research
    Keywords:    Agricultural R&D, field experimentation, crossbreeding, dairy, feeding technologies, mixed farming, farming systems research, modelling.

    Smallholder mixed crop livestock systems continue to be a dominant agricultural production system in many developing countries, includingIndia. Dairy farming is part and parcel of many such systems, and it is often seen as an important livelihood option to increase household income and to therefore contribute to poverty alleviation in rural areas. As a result, substantial efforts in agricultural R&D have been directed towards design of new technologies for smallholder dairy farming. Variable success in technology transfer has clearly shown that adoption is context-specific, related to the physical and socio-economic environment, access of farmers to resources, access to information and personal attitudes. A series of concepts and methods were developed to incorporate these considerations, and to replace narrow technology-driven approaches by broader ones such as Farming Systems Research (FSR).

    This thesis describes and analyses experiences of BAIF, an Indian NGO, with the use of FSR methodology in livestock development programmes inGujarat,India. The objectives were to identify criteria and methodologies for selection of appropriate livestock technologies for farm level, and to identify differences in the methods of selection of appropriate technology. Section 1 describes the variation in livestock production systems inIndiain general and in Gujarat-state. Livestock comprises defined and undefined breeds of cattle and buffalo. Total livestock population increased annually by over 1% in the last four decades, with buffalo and goat populations increasing faster than cattle. This section also gives background to the BAIF organization and to FSR methodologies. Section 2 more specifically describes theGujaratresearch area with agro-ecological zone-wise information on animal breeds, herd composition, feed resources, crops, and trends in seasonal availability of feed as derived from transects, Participatory Rural Appraisals, and mapping. Constraint analysis and modelling indicated limited genetic potential of the local breeds and shortage of feed resources, both quantitatively and qualitatively, as major constraints for livestock development. Crossbreeding for breed improvement and use of (improved) local feed resources were identified as suitable technologies to alleviate these constraints.

    Ex-post performance monitoring of some BAIF crossbreeding programmes show that crossbred cattle fitted well in the smallholder mixed farming systems of both tribal and non-tribal farmers in all three selected agro-ecological zones (Section 3). Milk production of crossbreds was substantially higher, as was livestock gross margin and household income. Although quality of the roughages is a major limiting factor, farmers owning crossbreds tried to adjust to the needs of the cows by feeding concentrates. There was no difference in workload and labour division between households with and without crossbreds. Crossbreeding thus proved a techno-economically and socially viable livelihood option for both mixed and landless farming systems inGujarat.

    Various modelling approaches were used in Section 4 to explore,ex ante,the suitability of feeding technologies such as urea supplementation, use of local and commercial concentrates, urea-treated straw with concentrates, and leuceana tree leaves for crop-livestock systems inGujarat,India. Major conclusions were that (i) concentrate feeding is beneficial to farmers with market access and crossbred cows, (ii) crossbreeding interventions are more remunerative for landless and tribal farmers than for non-tribal farmers; feeding interventions are more effective for crossbreds than for local cows, (iii) maximum farm income is achieved at medium milk yields per animal; higher milk yields require use of better feeds, which renders the straws of the grains useless for feeding; at farm level, the (economically) optimum cropping pattern would then shift from grain crops to cotton.This section continues with a narrative on BAIF's experiences with field testing of technologies at animal, at herd, at farm and watershed level, including a shift to crop research when dictated by local needs.Over a period of roughly 30 years, three phases in on-field testing can be distinguished, i.e., starting with a period of predominantly top-down approaches, moving to a phase with emphasis on participatory identification and testing of technologies, and then into a phase with work at community and watershed level. A few cases are discussed for each phase, illustrating the processes, methods and types of technologies involved, and drawing lessons on field experimentation for livestock and rural development in general. The studies brought out, among others, that adoption of technologies is facilitated when these use local (feed) resources, that are readily available, requires only small changes in farm practices, are relatively simple to implement, and yield tangible results in the short term.

    Section 5 analyses the dynamics in methods and approaches of BAIF's work on livestock development, as it grew from Gandhian roots into a large development organization. It emphasises the dynamics in approaches between top-down, objectivist and reductionist approaches on one hand and bottom-up, constructivist, holistic and self-organized approaches on the other hand. These experiences are set against similar developments on the (inter)national scene and in industrialized countries, along with factors that influence the changes, suggesting that agricultural R&D behaves as a complex adaptive system with its own dynamics and associated paradigm shifts. It also discusses a number of cross-cutting issues such as the notion of real versus perceived problems, hierarchy and grid, phases in development and aspects of holism versus reductionism, also reflected in notions of goal and process orientation.Concluding, the thesis considers development as a continuous process, of which the goals change over time-and-space. This reflects a paradigm issue, and if development is indeed a dynamic process it implies that choice of methodology and technology) should go along with changes occurring in that process. Some guidelines regarding the usefulness of approaches and technologies are given. But agricultural R&D is ultimately considered to be a complex adaptive system, also inGujarat, and development organizations such as BAIF have to, therefore, show dynamic behaviour.
    The role of fish ponds in the nutrient dynamics of mixed farming systems
    Muendo, P.N. - \ 2006
    Wageningen University. Promotor(en): Johan Verreth, co-promotor(en): Marc Verdegem; Jetse Stoorvogel. - [S.l. ] : S.n. - ISBN 9789085044598 - 120
    visvijvers - gemengde landbouw - voedingsstoffen - aquacultuur - visproductie - bedrijfssystemen - landbouwbijproducten - kringlopen - fish ponds - mixed farming - nutrients - aquaculture - fish production - farming systems - agricultural byproducts - cycling

    Rapid population growth in developing countries has resulted in increased demand for food, leading to increased pressure to extend land under cultivation and to intensify food production. Because most of the arable land has already been utilized, further intensification of agricultural production has involved conversion of marginal lands such as forest reserves, communal grazing land & and fragile areas such as river banks and steep hill slopes. Intensified crop production on marginal lands enhances the risk for soil degradation, like soil fertility decline. In many situations, inorganic fertilizers are not available or are too expensive, and efficient utilization of organic residues such as crop residues and manures is constrained by a temporal mismatch between availability and application. Diversification of farming activities potentially increases nutrient efficiencies. One promising additional activity is aquaculture and the development of integrated aquaculture - agriculture (IAA) systems.

    Although integrated aquaculture - agriculture farming systems have been developed and practiced in some parts of Asia, they have not been widely adopted. In many developing countries, especially in Africa, aquaculture itself is still poorly developed. Aquaculture is considered separately from agriculture and its benefits are measured in terms of fish production, ignoring its role in nutrient cycling through integrated farming systems. Yet, the majority of nutrients entering ponds, including fertilizers, feeds and nutrients contained in inflows from channels or run-off from watersheds, accumulate in the sediment. These nutrients are a potential nutrient source for terrestrial agriculture.

    This thesis explored the use of fish ponds as nutrient traps (besides fish production) to increase the nutrient use efficiency in mixed farming systems. Focus was put on (i) nutrient utilization efficiency of agricultural by-products such as crop residues and animal manure in aquaculture production, and(ii) in quantitative aspects of sediment and nutrient accumulation in aquaculture ponds, and pond sediments potential as a fertilizer in land-based agriculture.

    n chapter 2, aquaculture components were ideotyped for existing agricultural farming systems and benefits from resultant ideotyped integrated aquaculture - agriculture OAA) farming systems were evaluated and quantified. The results showed that integration of an aquaculture component in agricultural farming systems provided the opportunity to recycle eroded nutrients, in addition, aquaculture provided an opportunity to utilize nutrients from agricultural by-products otherwise lost through leaching during storage. As the majority of nutrients added to ponds accumulate in the sediment, nutrients are stored for later use. In different agro-ecological zones of the Kenyan highlands this practice reduced soil fertility decline by 23 - 35%, increased agricultural production by 2 - 26% and raised the overall farm food production by 22 - 70%. The results indicated that there may be more benefits from pond sediment utilization than fish production alone and also demonstrated that integration of aquaculture is not a threat to agricultural production. The nutrient storage capacity of ponds and the linked increase in productivity largely compensates for the small loss in land surface for crop production.

    In chapter 3, the nutrient utilization efficiency of agricultural by-products in fish ponds was investigated and compared to that of supplemental foods. Using multivariate analyses, the trophic pathways in organically fertilized and feed driven semi-intensive culture environments were explored. By ANOVA models, water quality, sediment quality and tilapia growth and yields in the two environments were also compared. In both environments, a phytoplankton based food web dominated, and fish nutrition in both environments was mainly based on natural foods. Extrapolated fish yield data indicated that with equal nutrient input and stocking density, organically fertilized environments could achieve production rates similar to those in feed driven environments. The results challenge the general assumption that supplemental or complete foods are well utilized by tilapia in ponds and underscore the need for further research on fish nutrition in ponds. In chapter 4, the sediment and nutrient accumulation in semi-intensive fish culture ponds within one culture period was quantified, the effect of input type (chicken manure vs. formulated feed) and stocking density (1 or 2 fishes m"2) on sediment and nutrient accumulation evaluated, and the accumulated sediment's potential for use in land-based agriculture estimated. An accumulation of up to 173 tons of sediment ha' cycle" (5 months) was observed in the semi-intensive production ponds and contained between 100 - 300kg of nitrogen, 1.8 - 5 tons of organic matter, 0.2 - 1.1 kg of available phosphorus and 50 - 125 kg of exchangeable potassium. Both sediment and nutrient accumulation were not affected by input type or stocking density. The results indicated that often reported accumulation of phosphorus in pond sediment may be in non-available forms. However, accumulated sediment had a high potential as nitrogen and potassium fertilizer and as a soil conditioner. By recommended Egyptian fertilization rates, the accumulated nutrients during a tilapia production cycle could potentially meet the nitrogen fertilizer requirement for 0.35 - 1.2 hectare and the potassium fertilizer requirement for 0.7 ~ 1.5 hectare.

    A part of the nutrients that accumulate in aquaculture ponds are lost through seepage. Normally, the assumption is made that seepage water and pond water have the same composition. In chapter 5, the use of rhizons as a standard methodology to measure the concentration of nutrients in seepage water was developed. The results showed that assuming identical chemical composition in seepage water and pond water results in an underestimation of nutrient losses due to seepage. Direct sampling of seepage water using rhizons provided a standardized and easy to use method to quantify nutrient losses due to seepage from earthen pond soils.

    The findings of this thesis are discussed in chapter 6 and main conclusions are given. The study demonstrated, from a bio-physical point of view, the technical feasibility of aquaculture - agricultural integration and the effect on nutrient cycling through the whole farming system. For further understanding of the benefits of IAA systems, future studies should asses the socio-economic feasibilities of IAA systems. The study has also shown mat agricultural by-products do not necessarily result in lower fish production compared to the use of formulated feeds. The results stress the need to search for new concepts for pond nutrition, as the present use of formulated diets serves more as an expensive fertilizer than a direct feed.

    Samen werken aan betere bodem
    Drenth, H. - \ 2005
    Oogst : weekblad voor de agrarische ondernemer. Landbouw 18 (2005)1. - ISSN 1566-2616 - p. 32 - 33.
    akkerbouw - akkerbouw- en tuinbouwbedrijven - melkveehouderij - melkveebedrijven - schapenhouderij - landbouwbedrijven - samenwerking - rotaties - pootaardappelen - voedergewassen - gemengde landbouw - meervoudig landgebruik - veehouderij - veehouderijbedrijven - landgebruik - grondbeheer - bodemvruchtbaarheid - bodemstructuur - bodembeheer - netwerken - friesland - arable farming - crop enterprises - dairy farming - dairy farms - sheep farming - farms - cooperation - rotations - seed potatoes - fodder crops - mixed farming - multiple land use - livestock farming - livestock enterprises - land use - land management - soil fertility - soil structure - soil management - networks - friesland
    Verslag van de samenwerking tussen twee akkerbouwers, een melkveehouder en een schapenhouder in Holwerd (Fr). De door hun opgerichte vereniging EcoLaNa beoogt een economisch en ecologisch verantwoorde landbouw waarin ook plaats is voor natuurbeheer. De boeren brengen samen 270 ha grond in en stellen gezamenlijk een bouwplan op voor hun 'gemengd bedrijf nieuwe stijl'. De bodemstructuur en de maatregelen die nodig zijn om die in stand te houden (vooral aanvoer van organische stof) zijn bepalend voor het bouwplan. Uitgangspunten van de samenwerking zijn dat de beste grond wordt benut voor de pootaardappelteelt en dat er voldoende gras en maïs wordt geproduceerd voor de melkkoeien. De vereniging EcoLaNa doet mee aan het onderzoeksprogramma 'Netwerken in de veehouderij'
    Neem alle belanghebbenden mee in het proces : nieuw gemengd bedrijf in Horst
    Noorduyn, L. - \ 2005
    Syscope Magazine 2005 (2005)8. - p. 6 - 7.
    gemengde landbouw - agrarische bedrijfsvoering - technische vooruitgang - gesloten systemen - glastuinbouw - systeeminnovatie - geïntegreerde bedrijfssystemen - mixed farming - farm management - technical progress - closed systems - greenhouse horticulture - system innovation - integrated farming systems
    Systeeminnovaties slagen alleen als belanghebbenden er vanaf het begin een stem in hebben. Dat is de overtuiging van de betrokkenen van het Nieuw Gemengd Bedrijf in Horst. Samen met onderzoekers, Transforum Agro & Groen en procesbegeleider Knowhouse bereiden de ondernemers het project zorgvuldig voor.
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