Interactions between broiler chickens, soil parameters and short rotation coppice willow in a free-range system
Stadig, Lisanne M. ; Tuyttens, Frank A.M. ; Rodenburg, T.B. ; Vandecasteele, Bart ; Ampe, Bart ; Reubens, Bert - \ 2019
Agroecology and Sustainable Food Systems 43 (2019)9. - ISSN 2168-3565 - p. 1009 - 1030.
agroforestry - biomass - carbon storage - nitrogen loss - poultry - Willow
Planting short rotation coppice willows (SRCW) in chickens’ free-range areas could have several advantages for the chickens, environment and farmer. Our aim was to test the effects of combining SRCW and chickens on free-range use, soil conditions and SRCW growth. A free-range chicken area was partially planted with a grass/clover mixture, and partially with SRCW. Chickens preferred to range in SRCW compared to grassland. No effects of periodical chicken presence on SRCW growth were observed. Total mineral N (Nmin) was affected by interactions between vegetation type, location, and soil depth; it was generally higher in SRCW than in grassland and in areas close to the chicken houses. Nmin did not appear to accumulate in the soil over the years, but there were strong indications for higher risk of N leaching to deeper soil layers and possibly to groundwater close to the houses and in SRCW. SRCW was beneficial for the chickens, but the combination needs to be studied further with a focus on strategies for preventing nutrient leaching to groundwater.
Enhancing agroecosystem productivity with woody perennials in semi-arid West Africa: a meta-analysis
Felix, G.F. ; Bayala, J. - \ 2018
Wageningen University & Research
agroforestry - ecological engineering - mulch - Sahel - shrub-crop associations - woody amendments
Dataset for meta-analysis about effects of parkland agroforestry systems and ramial wood amendment applications on crop yields and soil properties in semi-arid West Africa.
Trait-based approaches for guiding the restoration of degraded agricultural landscapes in East Africa
Lohbeck, Madelon ; Winowiecki, Leigh ; Aynekulu, Ermias ; Okia, Clement ; Vågen, Tor Gunnar - \ 2018
Journal of Applied Ecology 55 (2018)1. - ISSN 0021-8901 - p. 59 - 68.
agricultural land - agroecology - agroforestry - erosion - functional diversity - functional traits - land degradation - soil health - soil organic carbon - vegetation
Functional ecology provides a framework that can link vegetation characteristics of various land uses with ecosystem function. However, this application has been mostly limited to [semi-]natural systems and small spatial scales. Here, we apply functional ecology to five agricultural landscapes in Kenya, Uganda and Ethiopia, and ask to what extent vegetation characteristics contribute to soil functions that are key to farmers’ livelihoods. We used the Land Degradation Surveillance Framework (LDSF), a multi-scale assessment of land health. Each LDSF site is a 10 × 10 km landscape in which vegetation cover and erosion prevalence were measured, a tree inventory was carried out, and topsoil (0–20 cm) samples were collected for organic carbon (SOC) analysis in approximately 160 × 1,000 m2 plots. Land degradation is a recurring phenomenon across the five landscapes, indicated by high erosion prevalence (67%–99% of the plots were severely eroded). We used mixed models to assess if vegetation cover, above-ground woody biomass and the functional properties of woody vegetation (weighted-mean trait values, functional diversity [FD]) explain variation in SOC and erosion prevalence. We found that the vegetation cover and above-ground biomass had strong positive effects on soil health by increasing SOC and reducing soil erosion. After controlling for cover and biomass, we found additional marginal effects of functional properties where FD was positively associated with SOC and the abundance of invasive species was associated with higher soil erosion. Synthesis and applications. This work illustrates how functional ecology can provide much-needed evidence for designing strategies to restore degraded agricultural land and the ecosystem services on which farmers depend. We show that to ensure soil health, it is vital to avoid exposed soil, maintain or promote tree cover, while ensuring functional diversity of tree species, and to eradicate invasive species.
Walnotenboomgaard als pensioenvoorziening : bomen verdienen een plek in de landbouw, ter inspiratie een permacultuurontwerp
Zandbergen, Jelmer - \ 2017
Ekoland (2017)3. - ISSN 0926-9142 - p. 14 - 15.
walnoten - boomgaarden - juglon - agroforestry - bomen voor meerdere doeleinden - ecosysteemdiensten - walnuts - orchards - juglone - agroforestry - multipurpose trees - ecosystem services
Na de tweede wereldoorlog werden akkers en weilanden groter. Veel bomen werden gerooid en 200.000 km aan hagen verdween. Met de bijbehorende ecosysteemdiensten, zoals koolstofbinding en een microklimaat waar gewassen en dieren van profiteren. Nu is er weer meer aandacht voor het terugbrengen van bomen en hagen in de landbouw, zeker als ze naast de ecosysteemdiensten ook voedsel en hout produceren
The use of Eucalyptus in agroforestry systems of southern Rwanda : to integrate of segregate
Mugunga, C. - \ 2016
Wageningen University. Promotor(en): Frits Mohren; Ken Giller. - Wageningen : Wageningen University - ISBN 9789462577534 - 162
eucalyptus - agroforestry - eucalyptus saligna - zea mays - agroforestry systems - rotations - water use - rwanda - eucalyptus - agroforestry - eucalyptus saligna - zea mays - agroforestrysystemen - rotaties - watergebruik - rwanda
Effects of flow alteration on Apple-ring Acacia (Faidherbia albida) stands, Middle Zambezi floodplains, Zimbabwe
Gope, E.T. ; Sass-Klaassen, U.G.W. ; Irvine, K. ; Beevers, L. ; Hes, E.M. - \ 2015
Ecohydrology 8 (2015)5. - ISSN 1936-0584 - p. 922 - 934.
tree-rings - riparian vegetation - riverine ecosystems - growth - agroforestry - woodlands - ethiopia - regimes
The impounding of the Zambezi River by Kariba dam has regulated the river discharge of the Middle Zambezi river. This has been implicated in the failure of regeneration of Faidherbia albida in the downstream flood plain. This study aimed (1) to assess the effect of the altered flow regime of the river on the establishment and growth of F. albida on the Middle Zambezi floodplain and islands and (2) to test the potential of dendrochronology in detecting the age and long-term growth rates of F. albida in response to flow regime. Results indicated an uneven age distribution of F. albida stands on relatively ‘new islands’, dominated by young trees, while the floodplain and the ‘old island’ exhibited an even-aged stand but with a lack of regeneration, and a dying-off of older trees. The lack of F. albida establishment on the floodplain was linked to the decreased occurrence of flooding events, associated with a decrease in alluvial deposits, soil moisture and groundwater recharge. These effects may be enhanced by impact from browsers on regeneration of trees. Tree-ring analyses revealed the presence of distinct annual growth rings in F. albida and the applicability of dendrochronology for estimating F. albida population dynamics. The trees on the ‘new islands’ are younger and grow faster than those on the floodplain. Lack of competition and possible favourable moisture conditions suggest beneficial conditions for establishment and growth of the trees on the islands.
Constraints and opportunities for tree diversity management along the forest transition curve to achieve multifunctional agriculture
Ordonez, J.C. ; Luedeling, E. ; Kindt, R. ; Tata, H.L. ; Harja, D. ; Jamnadass, R. ; Noordwijk, M. van - \ 2014
Current Opinion in Environmental Sustainability 6 (2014). - ISSN 1877-3435 - p. 54 - 60.
ecosystem services - functional diversity - biodiversity - agroforestry - tropics - systems
On-farm tree diversity patterns result from a social-ecological process shaped by different actors. Farmer preferences, tree-site matching, seed dispersal, tree domestication and delivery via nurseries all play important roles in forming these patterns. As part of a wider interest in tree cover transition curves that link agroforestation stages of landscapes to a preceding deforestation process, we here focus on ‘tree diversity transition curves’ i. as a conceptual framework to understand current processes and how shifts in drivers affect tree diversity and ii. to help identify constraints and opportunities for interventions. We provide some examples of current research efforts and make suggestions for databases and analyzes that are required to improve our understanding of tree diversity transitions. We explore drivers, consequences and entry points for tree diversity management to achieve multifunctional agriculture.
Evaluating a non-destructive method for calibrating tree biomass equations derived from tree branching architecture
MacFarlane, D.W. ; Kuyah, S. ; Mulia, R. ; Dietz, J. ; Muthuri, C. ; Noordwijk, M. van - \ 2014
Trees-Structure and Function 28 (2014)3. - ISSN 0931-1890 - p. 807 - 817.
aboveground biomass - root architecture - fractal analysis - model - agroforestry - allometry - systems - forest - size
Functional branch analysis (FBA) is a promising non-destructive alternative to the standard destructive method of tree biomass equation development. In FBA, a theoretical model of tree branching architecture is calibrated with measurements of tree stems and branches to estimate the coefficients of the biomass equation. In this study, species-specific and mixed-species tree biomass equations were derived from destructive sampling of trees in Western Kenya and compared to tree biomass equations derived non-destructively from FBA. The results indicated that the non-destructive FBA method can produce biomass equations that are similar to, but less accurate than, those derived from standard methods. FBA biomass prediction bias was attributed to the fact that real trees diverged from fractal branching architecture due to highly variable length–diameter relationships of stems and branches and inaccurate scaling relationships for the lengths of tree crowns and trunks assumed under the FBA model.
Met bomen op landbouwgrond opbrengsten verhogen
Noordwijk, M. van - \ 2014
agroforestry - agroforestrysystemen - ontwikkelingslanden - kennis van boeren - ontwikkelingsstudies - kennisoverdracht - landbouw - agrosilviculturele systemen - duurzame landbouw - agroforestry systems - developing countries - farmers' knowledge - development studies - knowledge transfer - agriculture - agrosilvicultural systems - sustainable agriculture
Filmpje over agroforestry. Aan het woord is prof.dr. Meine van Noordwijk, buitengewoon hoogleraar Agroforestry aan Wageningen University. “We moeten ons realiseren dat op 43% van het landbouwareaal in de wereld bomen staan die voor minstens 10% de bodem bedekken. Het gaat dus om een landbouwareaal ter grootte van een continent".
Simulation of water-limited growth of the forage shrub saltbush (Atriplex nummularia Lindl.) in a low-rainfall environment of southern Australia
Descheemaeker, K.K.E. ; Smith, A.P. ; Robertson, M.J. ; Whitbread, A. ; Huth, N.I. ; Davoren, W. ; Emms, J. ; Llewellyn, R. - \ 2014
Crop and Pasture Science 65 (2014)10. - ISSN 1836-0947 - p. 1068 - 1083.
medicago-sativa l. - western-australia - farming systems - light interception - discharge areas - use efficiency - model - soil - agroforestry - crops
Old man saltbush (Atriplex nummularia Lindl.) is a useful forage shrub for livestock in the low-rainfall areas of the world, and particularly in Australia. In these semi-arid and arid environments, saltbush is valuable for increasing the production from otherwise marginal areas of the farm and during drought periods when there are few feed alternatives. The ability to predict the growth and development of perennial forages such as old man saltbush in response to rainfall, soils and farm management is necessary for farming system planning and design purposes. A field experiment was conducted at Waikerie, South Australia, to inform the development of a new forage shrub model for use in the APSIM framework. The model takes into account the common setup of saltbush plantations in alley systems, by simulating light interception and water uptake for interacting shrub and inter-row zones separately. This is done by modelling the canopy and root system development. Field data across three soil types along a landscape catena showed that the model was able to satisfactorily predict daily biomass accumulation, partitioning into leaf and woody biomass, and regrowth after grazing. The model was sensitive to properties associated with the root system, and with limited parameterisation can be tailored to simulate different clonal cultivars. The model can now be used in the APSIM framework to assess temporal and spatial dynamics of forage systems combining shrubs with herbaceous pasture components.
The 'One cow per poor family' programme: Current and potential fodder availability within smallholder farming systems in southwest Rwanda
Klapwijk, C.J. ; Bucagu, C. ; Wijk, M.T. van; Udo, H.M.J. ; Vanlauwe, B. ; Munyanziza, E. ; Giller, K.E. - \ 2014
Agricultural Systems 131 (2014). - ISSN 0308-521X - p. 11 - 22.
soil fertility management - exploring diversity - resource-allocation - central highlands - western kenya - napier grass - agroforestry - productivity - variability - growth
Livestock is an essential component of smallholder farming systems in the East African highlands. The ‘One cow per poor family’ programme was initiated in Rwanda as part of a poverty alleviation strategy, aiming to increase the livestock population. A four month-study was conducted in Umurera village (Simbi sector), southern Rwanda with the objectives to (1) quantify the on-farm fodder availability, (2) quantify the amount and quality of fodder on offer to livestock, (3) analyse potential fodder availability under five future scenarios and (4) evaluate the implications and feasibility of the programme. Farmers’ surveys, measurements of field sizes, together with daily measurements of fodder on offer, milk production and fodder refusals were conducted. Feeds used were diverse, comprising grasses (53%), banana plant parts (25%), residues of several crops (9%) and other plants (10%). Herbs collected from valley-bottoms, uncultivated grasses and crop residues were predominant fodder types on poorer (Resource group 1 – RG1) farms while Pennisetum and Calliandra were predominant fodder types for moderate (RG2) and better resource endowed (RG3) farms. The amount of fodder on offer for cattle ranged from 20 to 179 kg fresh weight animal-1 day-1 (9–47 kg DM). The milk yield ranged between 1.3 and 4.6 L day-1. The amount of Pennisetum and Calliandra fodder available decreased in the dry season with a concomitant increase in reliance on banana leaves and pseudo-stems. The poorest farmers (RG1) were not able to feed a local cow under all scenarios. RG2 farmers can sustain a local cow during both seasons when using all possible fodder resources, but can sustain a European cow under just two scenarios during the rainy season. RG3 farmers can feed a European cow during the rainy season under all scenarios and for four scenarios during the dry season. We conclude that the ‘One cow per poor family’ programme needs to be adjusted to increase its effectiveness. Our main recommendations are to shift to livestock that require less fodder, for example local cattle or small ruminants such as goats.
CoP in focus : community of practice on metropolitan food clusters, resource use efficiency and climate adaptation
Kranendonk, R.P. ; Hoechstetter, S. ; Castillo, A. ; Smeets, P.J.A.M. ; Mansfeld, M.J.M. van; Eetgerink, F. ; Cserhaty, M. ; Kalas, N. ; Schneider, U. - \ 2014
Wageningen : Alterra, Wageningen-UR (Alterra-report 2497) - 80
landbouw - landgebruik - broeikasgassen - kooldioxide - agroforestry - klimaatadaptatie - monitoring - landen van de europese unie - duitsland - intensieve veehouderij - de peel - agro-industriële ketens - agriculture - land use - greenhouse gases - carbon dioxide - agroforestry - climate adaptation - monitoring - european union countries - germany - intensive livestock farming - de peel - agro-industrial chains
This Pathfinder project develops a focused EU Community of Practice (CoP) on development of Agro food-clusters that focuses on innovation of high tech, large scale, industrialized and sustainable agriculture and food production for Metropoles. The Metropolitan food clusters significantly contribute to reduction of the carbon and water footprint of metropolitan areas. In the exchange of concepts, this CoP will work out the benefits for climate from MFC in real regional innovation trajectories, towards business cases. The focus will be on co creation in KENGi networks and applyimg the innovation pathways of MFC design.
Coffee farming and soil management in Rwanda
Nzeyimana, I. ; Hartemink, A.E. ; Graaff, J. de - \ 2013
Outlook on Agriculture 42 (2013)1. - ISSN 0030-7270 - p. 47 - 52.
erosion control - agroforestry - plantations - systems - mexico
Agriculture is the cornerstone of Rwanda's economy. The authors review how the sector has changed and specifically what soil management practices are now being implemented to enhance coffee production. Coffee covers around 2.3% of total cultivated arable land, and is grown mainly by smallholder farmers on plots of less than one hectare. Rwanda produces high-quality speciality or fully washed coffee, which is intercropped with annual crops due to land scarcity to enable farmers to achieve a better combination of food and cash crops. Most of the agricultural soils have a pH of <5.2 and are highly deficient in phosphorus. Reduced land fragmentation, increased organic and inorganic fertilizer applications and mulching are all needed to boost yields. These practices will also help to improve the soils' chemical and physical properties and control erosion on the steep cultivated slopes.
Political ecology in the oil palm-based cropping system on the Adja plateau in Benin: connecting soil fertility and land tenure
Yemadje, H.R.M. - \ 2013
Wageningen University. Promotor(en): Thomas Kuijper; R. Mongbo; D.K. Kossou, co-promotor(en): Todd Crane. - Wageningen : Wageningen UR - ISBN 9789461737557 - 111
teeltsystemen - oliepalmen - ecologie - politiek - bodemvruchtbaarheid - pachtstelsel - innovaties - landhervorming - sociale verandering - intensivering - agroforestry - benin - cropping systems - oil palms - ecology - politics - soil fertility - tenure systems - innovations - land reform - social change - intensification - agroforestry - benin
Keywords: Innovation system, Soil fertility management, Land reform, Participatory technology development, Social change, Agroforestry, Land access rights, Fallow, Agricultural intensification, Africa
On the Adja plateau (West Benin), multiple actors are involved in an intercropping system with oil palm and food crops. This system is known as the oil palm-based cropping system (OPBCS). It contains two stages: a stage of small oil palms underneath which food crops are grown and a fallow stage with mature oil palm. Landowners grow oil palm mainly for the artisanal production of palm wine and sodabi, rather than for palm oil, for which the region is unsuitable for climatological reasons. The OPBCS has to be analysed not only from a technical and ecological perspective, but also from an institutional one. In the OPBCS there are competing claims between landowners and tenants for land use. Tenants access land under specific customary rules, grow food crops beneath oil palm and extend the cropping period by severely pruning palms because their right to grow food crops terminates when the palms reach a height of 2 m. Landowners claim that extended cropping reduces soil fertility and that long-duration oil palm fallows are necessary for soil fertility regeneration. Tenants state that long-duration fallow maintains land scarcity. In an attempt to remedy the competing claims, a land titling programme was implemented in some villages on the Adja plateau.
I analysed the system with a political ecology lens. I demonstrated the implications of the multiple institutions for land access and ownership, and therefore for the competing claims. Land titling initially created land insecurity for tenants, as they were thrown off the land by owners who wanted to demonstrate ownership. Subsequently, new rules related to land access by tenants were introduced. Both ownership and access by tenants relied on a different mix of formal and informal practices, as evidenced by formal contracts, petits papiers and a new paper contract. The new paper contract provides tenants the rights to rent the land for up to 25 years. The titling programme also enhanced on-going processes of intensification and commercialisation, as evidenced by increased use of mineral fertiliser and the regression of the OPBCS. The long-duration fallow periods did not improve biological and chemical soil fertility. Long-duration fallows are rather used as an expression of control over land. Mineral fertiliser and organic amendments (household waste) explain lack of effects of fallowing. Application of household waste and mineral fertiliser did not change soil organic matter content. Organic amendments increased maize yields more than mineral fertiliser. Household waste did not improve agronomic use efficiency of mineral fertiliser.
I suggest that formal and customary land tenure institutions can be blended to generate a hybrid system. Such a hybrid system might contribute to sustainable soil fertility management.
Tailoring agroforestry technologies to the diversity of Rwandan smallholder agriculture
Bucagu, C. - \ 2013
Wageningen University. Promotor(en): Ken Giller, co-promotor(en): Mark van Wijk; B. Vanlauwe. - Wageningen : Wageningen University - ISBN 9789461733658 - 252
agroforestry - voedselzekerheid - landbouw - kleine landbouwbedrijven - voedselproductie - bedrijfssystemen - kunstmeststoffen - afrika ten zuiden van de sahara - agroforestry - food security - agriculture - small farms - food production - farming systems - fertilizers - africa south of sahara
Keywords: food security, biophysical and socioeconomic conditions, farmer resource groups, productivity, economic evaluation, scenario analysis
Smallholder livelihoods in sub-Saharan Africa(SSA) are constrained by a number of factors that limit food production and thereby threaten food security. Soil fertility is one of the major factors explaining the decrease in per capita food production in SSA. Nutrient deficiencies in particular N and P severely limit agricultural production in many regions in the tropics. Supply of adequate amounts of nutrients throughfertiliserapplication is therefore a prerequisite to balance soil fertility budgets and to boost food production. However, mineral fertilisers are not accessible to the large majority of smallholder farmers. Farmyard manure, an important source of organic fertiliser for smallholder farmers, is available at limited quantities due to low livestock densities in many regions, for example Rwanda. Agroforestry, a low-input technology, was shown to contribute to the enhancement of food production while ensuring sustainability in sub-Saharan Africa.Agroforestry may contribute to soil fertility by increasing nutrient availability and providing other various benefits and services. However, to be successful agroforestry technologies need to match the characteristics of different smallholder farming systems, like for example soil fertility status, socioeconomic status and farmer management. These factors are rarely studied in an integrated manner.
This thesis aims to understand and characterise different farming systems, evaluate the potential for the most promising agroforestry practices and suggest the most suitable agroforestry recommendations for different farming systems in targeted agro-ecological zones of Rwanda. The approach combined characterization of farming systems, participatory tree testing, farmer’s evaluations of technologies, and scenario and trade-off analyses in two agro-ecological zones: Central Plateau (moderate altitude) and Buberuka (high altitude zone). Two locations, Simbi and Kageyo sectors were selected as representative study sites. Wealth ranking techniques allowed the identification of three farm resource groups (RGs). Though three farmer classes were identified in the two locations and referred as RG 1, RG 2 and RG 3 respectively, farmer classes were unique to each location. Averaged over sampled villages, 76% of all households belong to RG 1 class in Simbi versus 67% in Kageyo. This least resourced group with on average 0.20 ha of land and with 1 goat wasthe most vulnerable farmer groupin terms of food security (20 to 25% protein deficient).RG 2 (9 to 31%) was intermediate between RG 1 and RG 3. RG 3 (2 to 7 %) was the wealthiest (1 to 3 ha, 2 or more cattle) and food-secure for at least 10 months. Soil nutrient balances were negative in most farms due to small amounts of nutrients applied, which did not compensate for nutrient removal during harvest. From an agroforestry perspective, Simbi contrasted with Kageyo in tree diversity and density but tree niches and management were similar between the locations. The main agroforestry species may becategorisedinto three classes including timber, legume and fruit tree species based on the main functions. The results clearly indicated the need to improve soil fertility and food production using integrated soil fertility approaches that promote a combined use of agroforestry resources and other fertiliser sources to replenish the soil nutrients and improve the efficiency and cost effectiveness of inputs use at farm level.
Experiments evaluated the potential effects of agroforestry species on production within different farming systems. Tephrosia species were tested as a source of mulch in coffee plantations in the Central Plateau agro-ecological zone. Application of Tephrosia mulch resulted in higher biomass and better economic returns when established in coffee fields, particularly when Tephrosiamulch was combined with NPK. Application of prunings of Calliandra increased maize productivity, net returns and the ratio between gross margin and costs of inputs on all farms except the richest farms. This positive effect of Calliandra was larger in Kageyo than in Simbi. The effect was even more pronounced with P application. The results indicated that fields responded differently within farms, and significant differences between locations were present.
The assessment of fodder availability within different farming systems revealed that animal feeds are widely diversified, with Pennisetum being largely used in wealthier farms (RG 3), while RG 1 farmers use larger quantities of marshland-herbs and crop residues.There was a strong variation in seasonal feed availability. Napier and Calliandra were more available during the wet season, while banana pseudo-stems were used more in the dry seasons. Quantification of the year-round fodder availability showed that RG 1 farmers are unable to keep a cow, while RG 2 and RG 3 could keep local or improved cows under specific scenarios. Biophysical (rainfall, field type) and socio-economic conditions (wealth status) as well as farmer preferences were factors influencing the choice and performance of agroforestry technologies. The study recommends revisiting current agroforestry research policies and taking into account farmer’s preferences as priorities in the agroforestry research agenda.
Soil erosion, soil fertility and crop yield on slow-forming terraces in the highlands of Buberuka, Rwanda
Kagabo, M.D. ; Stroosnijder, L. ; Visser, S.M. ; Moore, D. - \ 2013
Soil & Tillage Research 128 (2013). - ISSN 0167-1987 - p. 23 - 29.
spatial variability - andes region - conservation - systems - water - land - agroforestry - hedgerows - ecuador - strips
Crop productivity in Rwanda is declining as a result of intensive farming on steep slopes, which leads to soil loss and declining soil fertility particularly in the northern highlands. Slow-forming terraces have been widely adopted in the northern highlands of Rwanda to control soil erosion however not much been done to evaluate their efficiency. We hypothesized that slow-forming terraces reduce soil loss and soil fertility gradients compared with non-conserved land. A field experiment compared the soil erosion rates and fertility gradients of 20+ year old terraces where sole grass strips (Pennisetum purpureum) or grass strips combined with infiltration ditches were used with those of land where no soil conservation technologies were applied. The experiment was conducted in the year 2010 on three landscape positions (Upperslope, Hillslope and Footslope) along a representative toposequence using farmers’ fields where potato and maize were grown in two consecutive cropping seasons. The highest annual soil loss (41.5 t ha-1) was recorded with plots receiving no soil conservation practices while the lowest annual soil loss (18 t ha-1) was recorded with grass strips combined with infiltration ditches. The slow-forming terraces showed a marked “within” spatial difference in both soil quality and crop yield. The soil in the lower part of the terraces showed as much as 57% more organic carbon content and 31% more available phosphorous than the soil in the upper part. Organic carbon (OC) was higher (OC = 2.1%) on the upperslope than on hillslope (OC = 1.9%). Less than 2.3 t ha-1 of the mean potato yield (23 t ha-1) and only 0.5 t ha-1 of the mean maize yield (5 t ha-1) were recorded on the uppermost third of the terraces on all three landscape positions. The marked soil fertility gradients indicate that the sustainability of slow-forming terraces is threatened, unless a site-specific fertilizer strategy is developed. For the sustainability of these terraces, the current practice of “harvesting” the fertile soil from the lower edge of the grass strip and using it as fertilizer for the nutrient deficient upper parts of terraces needs to be stopped
Farm woodlots in rural Rwanda: purposes and determinants
Ndayambaje, J.D. ; Heijman, W.J.M. ; Mohren, G.M.J. - \ 2013
Agroforestry Systems 87 (2013)4. - ISSN 0167-4366 - p. 797 - 814.
central highlands - tree - agroforestry - ethiopia - management - landscape - patterns - systems - malawi - diversity
The development of farm woodlots as an alternative source of livelihood for smallholder farmers in diverse biophysical and socio-economic conditions is a challenging issue in developing countries, such as Rwanda, where the majority of the population relies on subsistence farming. There is a need to understand why and when farmers decide to grow trees and woodlots on their farms. The objective of this study was to analyse the determinants and the purposes that enhance the propensity to grow woodlots in low, medium and high altitude regions of Rwanda. Necessary information for this study came from a survey of 480 households across these regions. The results showed regional variations in the determinants of woodlot farming, demonstrating the importance of not extrapolating the results between regions. Pooled data across regions indicated that age of the householder, number of salaried household members, farm size, travel distance to fuelwood sources and household location in medium forest cover region had positive significant effects on the propensity to grow farm woodlots. In contrast, household location in low forest cover region, ownership of livestock and monthly frequency of purchasing fuelwood were inversely related to the presence of farm woodlots. Many households planted eucalyptus woodlots for economic reasons, not for environmental purposes. Livestock and crop production were more attractive to rural households than woodlot farming. The findings of the study can be used by policymakers and extension services in order to promote sustainable land use practices by focusing on the challenges of competing land uses, farm size, unemployment, dependence on forests for fuelwood supply and subsistence farming.
Biosocial and bionumerical diversity of variously sized home gardens in Tabasco, Mexico
Wal, J.C. van der; Bongers, F. - \ 2013
Agroforestry Systems 87 (2013)1. - ISSN 0167-4366 - p. 93 - 107.
species richness - tropical forest - costa-rica - biodiversity - homegardens - plant - conservation - agroforestry - kerala - india
The evaluation of species and structural diversity of home gardens strongly depends on the methods used. We distinguish the biosocial and the bionumerical method. The first is widely used and takes data of the whole population of trees of home gardens to calculate diversity. The bionumerical method calculates diversity from data of a fixed number of randomly selected trees. We apply both methods to analyze if structural and species diversity varies with home garden size, a theme of considerable conservation interest, and compare results. We inventoried the tree component of a sample of 61 home gardens from rural areas in Tabasco, Mexico, which we assigned to three size categories: small (=1,000 m2), medium sized (>1,000 and =2,000 m2), and large home gardens (>2,000 m2). Average species richness and Shannon diversity indices determined by the biosocial method were significantly different among home garden size classes. Average species richness determined by the bionumerical method did not differ among size classes. Both methods showed highest total observed and estimated species richness in the large home gardens, which contain many unique species. Both methods showed similar overall species composition among size classes and highest structural diversity in large home gardens. We conclude that it is important for conservation to maintain large home gardens in local mosaics, and that the biosocial and bionumerical methods are complementary. The bionumerical method allows straight comparison of population diversity within and among systems, but lacks attention for rare and unique species. The biosocial method evaluates how much diversity families custody.
Forest-people interfaces : understanding community forestry and biocultural diversity
Arts, B.J.M. ; Bommel, S. van; Ros-Tonen, M.A.F. ; Verschoor, G.M. - \ 2012
Wageningen : Wageningen Academic Publishers - ISBN 9789086867493 - 317
bossen - bosbouw - agroforestry - sociale bosbouw - bosproducten anders dan hout - bosproducten - mensen - gemeenschapsbosbouw - natuurlijke hulpbronnen - hulpbronnenbeheer - bosbedrijfsvoering - bosbeleid - forests - forestry - agroforestry - social forestry - non-wood forest products - forest products - people - community forestry - natural resources - resource management - forest management - forest policy
This book aims at both academics and professionals in the field of forest-people interfaces. It takes the reader on a journey through four major themes that have emerged since the initiation of 'social forestry' in the 1970s: non-timber forest products and agroforestry; community-based natural resource management; biocultural diversity; and forest governance. In so doing, the books offers a comprehensive and current review on social issues related to forests that other, more specialized publications, lack. It is also theory-rich, offering both mainstream and critical perspectives, and presents up-to-date empirical materials. Reviewing these four major research themes, the main conclusion of the book is that naïve optimism associated with forest-people interfaces should be tempered. The chapters show that economic development, political empowerment and environmental aims are not easily integrated. Hence local landscapes and communities are not as 'makeable' as is often assumed. Events that take place on other scales might intervene; local communities might not implement policies locally; and governance practices might empower governments more than communities. This all shows that we should go beyond community-based ideas and ideals, and look at practices on the ground.
Biodiversity and key ecosystem services in agroforestry coffee systems in the Brazilian Atlantic Rainforest Biome
Souza, H.N. de - \ 2012
Wageningen University. Promotor(en): Lijbert Brussaard; I.M. Cardoso, co-promotor(en): Mirjam Pulleman; Ron de Goede. - S.l. : s.n. - ISBN 9789461731098 - 156
agroforestry - biodiversiteit - ecosysteemdiensten - coffea - duurzaamheid (sustainability) - agroforestrysystemen - tussenteelt - inheemse planten - regenbossen - brazilië - agroforestry - biodiversity - ecosystem services - coffea - sustainability - agroforestry systems - intercropping - native plants - rain forests - brazil
The thesis reports the results of long-term experimentation (since 1993) of family farmers with agroforestry (AF) coffee systems in the Brazilian Atlantic Rainforest region, a highly fragmented and threatened biodiversity hotspot. The farmers used native trees from forest fragments during a transition from the predominant full sun-coffee (SC) production to more diversified agriculture. The aim of the research was to gain understanding of different agricultural management systems within the complex landscape matrix with respect to farmers’ capacity to diminish negative impacts on the environment, based on an ecosystem services approach.
Participatory Rural Appraisal was used to obtain data from the family farmers. A method of systematization of their experiments created platforms for reflexion and development of agroforestry systems for farmers, technicians and researchers beyond only listing the negative and positive results. Long-term effects of coffee agroforestry (AF), full-sun coffee (SC) systems and surrounding reference forest fragments (RF) were assessed on: tree biodiversity, microclimate, soil quality, costs of labour and inputs and profitability. Selection of appropriate tree species was essential to the success of agroforestry. The main criteria for selecting tree species by farmers were: compatibility with coffee, amount of tree biomass produced, diversification of the production and the labour needed for tree management. The farmers used 85 tree species across the area, 28 of which belonged to the Leguminosae, a family of nitrogen-fixing plants. Most trees were either native to the biome, or exotic fruit trees. The diversification of production, especially with fruit trees, contributed to food security and to a low cost/benefit ratio of AF.
Comparisons between reference forest fragments, agroforestry coffee and sun coffee revealed the potential of AF to conserve local tree biodiversity. Litter quality on-farm was functional in terms of soil erosion and fertility management. The canopy of the trees mitigated high temperature extremes: maximum temperature in SC systems (32oC) was 5.4 oC higher than in AF. Some soil quality parameters (total organic carbon, microbial carbon, soil respiration and potential nitrogen mineralization) showed higher values in RF than AF and SC, but no differences were observed between AF and SC.
There was considerable diversity in the strategies and management of farmers for AF (including the choice of tree species), affecting the productivity and profitability. The total production value of AF was on average 43% higher than that of SC, largely due to other products than coffee. Both systems had an overall higher return of labour than the wage rate in the area.
Continued participative work among scientists and stakeholders may help to increase the delivery of ecosystem services provided by family agriculture. Production systems based on ecosystem service delivery beyond just crop production have potential to reduce the need for external inputs and contribute to major local, regional and global objectives, such as food security, adaptation to climate change and conservation of biodiversity.