Comparative study of nitrate leaching models on a regional scale
Roelsma, J. ; Hendriks, R.F.A. - \ 2014
Science of the Total Environment 499 (2014). - ISSN 0048-9697 - p. 481 - 496.
agricultural land-use - soil-crop model - groundwater nitrate - sandy soils - drinking-water - system stone - netherlands - nitrogen - losses - simulation
In Europe and North America the application of high levels of manure and fertilisers on agricultural land has led to high levels of nitrate concentrations in groundwater, in particular on sandy soils. For the evaluation of the development of the quality of groundwater a sound quantitative basis is needed. In this paper a comparison has been made between observations of nitrate concentrations in the upper groundwater and predictions of nitrate leaching models. Observations of nitrate concentrations in the upper groundwater at three different locations in regions with mainly sandy soils in the eastern and northern part of the Netherlands were used to test the performance of the simulation models to predict nitrate leaching to the upper groundwater. Four different types of simulation models of different levels of complexity and input data requirement were tested. These models are ANIMO (dynamic complex process oriented model), MM-WSV (meta-model), WOG (simple process oriented model) and NURP (semi-empiric model). The performance of the different simulation models was evaluated using statistical criteria. The dynamic complex process oriented ANIMO model showed the best model performance. The MM-WSV meta-model was the second best model, whilst the simple process oriented WOG model produced the worst model performance. The best model performance showed the dynamic complex process oriented ANIMO model in predicting the nitrate concentrations in the upper groundwater of the Klooster catchment. The good performance of the ANIMO model for this catchment can be explained by the additional information about the use of manure and fertilisers at farm level in this study area. The ANIMO model may be a good tool to predict nitrate concentrations in the upper groundwater on a regional scale. However, the use of a detailed process oriented simulation model requires a comprehensive set of input data. If such a comprehensive data-set is not available the MM-WSV model (meta-model) proves to be a good alternative. The WOG and NURP models are suitable for long term (>8 years) predictions of average nitrate concentrations in the upper groundwater on a regional scale. (C) 2014 Elsevier B.V. All rights reserved.
From global economic modelling to household level analyses of food security and sustainability: how big is the gap and can we bridge it?
Wijk, M.T. van - \ 2014
Food Policy 49 (2014)2. - ISSN 0306-9192 - p. 378 - 388.
agricultural land-use - integrated assessment - climate-change - production systems - farming systems - earth system - cover change - east-africa - challenges - science
Policy and decision makers have to make difficult choices to improve the food security of local people against the background of drastic global and local changes. Ex-ante impact assessment using integrated models can help them with these decisions. This review analyses the state of affairs of the multi-scale modelling of policy interventions, with an emphasis on applications in developing countries and livestock systems. Existing models do not sufficiently capture the complexity of human-environment interactions across different scales, and especially the link between landscape and local market levels, and national and sub-national level policies and markets is missing. The paper suggests a step wise approach with increasing data needs to bridge this gap. Improvements need to be made at the description of effects of the distribution of local markets on price formation and the representation of farm diversity within a landscape. Analyses in contrasting agro-ecological systems are needed to derive generic summary functions that can be used as input for macro level model analyses. This is especially pertinent for macro level descriptions of crop and livestock production in relation to price developments and of the mosaic of different agricultural land use responses in regions with contrasting socio-economic conditions and developments.
Assessing climate change and associated socio-economic scenarios for arable farming in the Netherlands: An application of benchmarking and bio-economic farm modelling
Kanellopoulos, A. ; Reidsma, P. ; Wolf, J. ; Ittersum, M.K. van - \ 2014
European Journal of Agronomy 52 (2014)Part A. - ISSN 1161-0301 - p. 69 - 80.
akkerbouw - klimaatverandering - opbrengsten - groeimodellen - scenario-analyse - alternatieve landbouw - arable farming - climatic change - yields - growth models - scenario analysis - alternative farming - agricultural land-use - integrated assessment - european-community - future - crop - efficiency - impacts - systems
Future farming systems are challenged to adapt to the changing socio-economic and bio-physical environment in order to remain competitive and to meet the increasing requirements for food and fibres. The scientific challenge is to evaluate the consequences of predefined scenarios, identify current “best” practices and explore future adaptation strategies at farm level. The objective of this article is to assess the impact of different climate change and socio-economic scenarios on arable farming systems in Flevoland (the Netherlands) and to explore possible adaptation strategies. Data Envelopment Analysis was used to identify these current “best” practices while bio-economic modelling was used to calculate a number of important economic and environmental indicators in scenarios for 2050. Relative differences between yields with and without climate change and technological change were simulated with a crop bio-physical model and used as a correction factors for the observed crop yields of current “best” practices. We demonstrated the capacity of the proposed methodology to explore multiple scenarios by analysing the importance of drivers of change, while accounting for variation between individual farms. It was found that farmers in Flevoland are in general technically efficient and a substantial share of the arable land is currently under profit maximization. We found that climate change increased productivity in all tested scenarios. However, the effects of different socio-economic scenarios (globalized and regionalized economies) on the economic and environmental performance of the farms were variable. Scenarios of a globalized economy where the prices of outputs were simulated to increase substantially might result in increased average gross margin and lower average (per ha) applications of crop protection and fertilizers. However, the effects might differ between different farm types. It was found that, the abolishment of sugar beet quota and changes of future prices of agricultural inputs and outputs in such socio-economic scenario (i.e. globalized economy) caused a decrease in gross margins of smaller (in terms of economic size) farms, while gross margin of larger farms increased. In scenarios where more regionalized economies and a moderate climate change are assumed, the future price ratios between inputs and outputs are shown to be the key factors for the viability of arable farms in our simulations
Convergence of European wheat yields
Powell, J.P. ; Rutten, M.M. - \ 2013
Renewable and Sustainable Energy Reviews 28 (2013). - ISSN 1364-0321 - p. 53 - 70.
agricultural land-use - panel-data - model - productivity - estimators - regression - scenarios - emissions - gas
The paper makes several contributions to the study of wheat yield changes in Europe and the resulting economic consequences in the near to medium term future. In particular, it addresses the issue of the effects of yield changes on land use. The transition and growth of yields are estimated using a combination of convergence, time-series and dynamic panel models. Scenarios are then run using estimated yields as input into a computable general equilibrium (CGE) model. The CGE model provides a narrative framework through which the total economic impact of changes in yields can be analyzed. Together, the complementary approaches of econometrics and general equilibrium models allow a more complete economic analysis of the consequences of yield changes for this important biofuels crop to emerge. Although there is no evidence of a common rate of yield convergence across Europe, there is evidence of absolute convergence. Standard time series and panel forecasting methods indicate the potential for only very modest yearly yield increases across most of Europe given optimistic assumptions; although potential yearly increases in newer European states could, in some cases, be substantially higher. However, the total amount of land released as a result of potential yield increases in the wheat sector is only modest because of an increase in demand for land by sectors other than wheat. The overall question of whether significant yield increases will necessarily lead to large increases in land available to produce bio-energy crops is rejected. Land freed by wheat yield increases will go to the production of a wide range of agricultural products that value it as an input. The same reasoning which links yields and land use applies to all agricultural products when there are well functioning markets. (C) 2013 Elsevier Ltd. All rights reserved.
Combining qualitative and quantitative understanding for exploring cross-sectoral climate change impacts, adaptation and vulnerability in Europe.
Harrison, P.A. ; Holman, I.P. ; Cojocaru, G. ; Kok, K. ; Kontogianni, A. ; Metzger, M.J. ; Gramberger, M. - \ 2013
Regional Environmental Change 13 (2013)4. - ISSN 1436-3798 - p. 761 - 780.
global water-resources - agricultural land-use - north-west england - integrated assessment - east-anglia - model - scenarios - policy - scale - coastal
Abstract Climate change will affect all sectors of society and the environment at all scales, ranging from the continental to the national and local. Decision-makers and other interested citizens need to be able to access reliable science-based information to help them respond to the risks of climate change impacts and assess opportunities for adaptation. Participatory integrated assessment (IA) tools combine knowledge from diverse scientific disciplines, take account of the value and importance of stakeholder ‘lay insight’ and facilitate a two-way iterative process of exploration of ‘what if’s’ to enable decision-makers to test ideas and improve their understanding of the complex issues surrounding adaptation to climate change. This paper describes the conceptual design of a participatory IA tool, the CLIMSAVE IA Platform, based on a professionally facilitated stakeholder engagement process. The CLIMSAVE (climate change integrated methodology for cross-sectoral adaptation and vulnerability in Europe) Platform is a user-friendly, interactive web-based tool that allows stakeholders to assess climate change impacts and vulnerabilities for a range of sectors, including agriculture, forests, biodiversity, coasts, water resources and urban development. The linking of models for the different sectors enables stakeholders to see how their interactions could affect European landscape change. The relationship between choice, uncertainty and constraints is a key cross-cutting theme in the conduct of past participatory IA. Integrating scenario development processes with an interactive modelling platform is shown to allow the exploration of future uncertainty as a structural feature of such complex problems, encouraging stakeholders to explore adaptation choices within real-world constraints of future resource availability and environmental and institutional capacities, rather than seeking the ‘right’ answers.
Nutrient flows and balances in urban and peri-urban agroecosystems of Kano, Nigeria
Abdulkadir, A. ; Leffelaar, P.A. ; Agbenin, J.O. ; Giller, K.E. - \ 2013
Nutrient Cycling in Agroecosystems 95 (2013)2. - ISSN 1385-1314 - p. 231 - 254.
sub-saharan africa - dissolved organic nitrogen - vegetable farming systems - agricultural land-use - northern nigeria - water-quality - waste-water - west-africa - economic-performance - exchange equilibria
Nutrient balances are useful indicators to assess the sustainability of farming systems. This study study investigates inflow and outflow of major nutrients in urban and periurban production systems in Kano, Nigeria. To this end, 16 households representing three different urban and peri-urban (UPA) farming systems were studied using the MONQI toolbox (formerly known as NUTMON) to calculate nutrient flows and economic performances. The farm nitrogen (N) balance was positive at 56.6, 67.4 and 56.4 kg farm-1 year-1 for commercial garden and crop-livestock (cGCL), commercial gardening and semi-commercial livestock (cGscL) and commercial livestock subsistence field cropping (cLsC) farm types, respectively. The same trend was observed for phosphorus (P) and potassium (K) in all farm types except an annual negative K balance of 16 kg farm-1 in cGCL. Across the different activities within the farms, land uses had positive N (359, 387 and 563 kg N ha-1 year-1) and P (74, 219 and 411 kg P ha-1 year-1) balances for all farm types, but again a negative K balance in cGCL with an average loss of 533 kg K ha-1 year-1. Partial nutrient balances in livestock production indicated a positive balance for all nutrients across the farms types but were slightly negative for P in cLsC. Commercial livestock keeping (cLsC) was economically more profitable than the other farm types with an average annual gross margin (GM) and net cash flow (NCF) of 9,033and 935. Cropping activities within cGCL and cGscL had GMs of 1,059and 194 and NCFs of 757and 206, respectively, but livestock activities in both farm types incurred financial losses. Potassium inputs were limited under vegetable and crop production of cGCL, threatening long-term K nutrient availability in this system. Overall, the results indicated large annual surpluses of N and P in urban and peri-urban vegetable and crop production systems which pose a potential threat when lost to the environment. Appropriate policies should aim at promoting sustainable production through efficient nutrient management in the Kano UPA sector.
Scenarios of long-term farm structural change for application in climate change impact assessment
Mandryk, M. ; Reidsma, P. ; Ittersum, M.K. van - \ 2012
Landscape Ecology 27 (2012)4. - ISSN 0921-2973 - p. 509 - 527.
klimaatadaptatie - klimaatverandering - landbouw - structurele verandering - agrarische bedrijfsvoering - bedrijfsstructuur in de landbouw - scenario-analyse - flevoland - nederland - climate adaptation - climatic change - agriculture - structural change - farm management - farm structure - scenario analysis - flevoland - netherlands - agricultural land-use - future - policy - adaptation - diversification - vulnerability - productivity - consequences - variability - performance
Towards 2050, climate change is one of the possible drivers that will change the farming landscape, but market, policy and technological development may be at least equally important. In the last decade, many studies assessed impacts of climate change and specific adaptation strategies. However, adaptation to climate change must be considered in the context of other driving forces that will cause farms of the future to look differently from today’s farms. In this paper we use a historical analysis of the influence of different drivers on farm structure, complemented with literature and stakeholder consultations, to assess future structural change of farms in a region under different plausible futures. As climate change is one of the drivers considered, this study thus puts climate change impact and adaptation into the context of other drivers. The province of Flevoland in the north of The Netherlands was used as case study, with arable farming as the main activity. To account for the heterogeneity of farms and to indicate possible directions of farm structural change, a farm typology was developed. Trends in past developments in farm types were analyzed with data from the Dutch agricultural census. The historical analysis allowed to detect the relative importance of driving forces that contributed to farm structural changes. Simultaneously, scenario assumptions about changes in these driving forces elaborated at global and European levels, were downscaled for Flevoland, to regional and farm type level in order to project impacts of drivers on farm structural change towards 2050. Input from stakeholders was also used to detail the downscaled scenarios and to derive historical and future relationships between drivers and farm structural change. These downscaled scenarios and future driver-farm structural change relationships were used to derive quantitative estimations of farm structural change at regional and farm type level in Flevoland. In addition, stakeholder input was used to also derive images of future farms in Flevoland. The estimated farm structural changes differed substantially between the two scenarios. Our estimations of farm structural change provide a proper context for assessing impacts of and adaptation to climate change in 2050 at crop and farm level
Landscape-mediated biodiversity effects of agri-environmental management - a meta-analysis.
Batáry, P. ; Báldi, A. ; Kleijn, D. ; Tscharntke, T. - \ 2011
Proceedings of the Royal Society. B: Biological Sciences 278 (2011)1713. - ISSN 0962-8452 - p. 1894 - 1902.
agricultural land-use - file-drawer problem - farmland biodiversity - ecosystem service - natural enemies - pollinator diversity - european countries - biological-control - crop pollination - habitat
Agri-environmental management (AEM) is heralded as being key to biodiversity conservation on farmland, yet results of these schemes have been mixed, making their general utility questionable. We test with meta-analysis whether the benefits of AEM for species richness and abundance of plants and animals are determined by the surrounding landscape context. Across all studies (109 observations for species richness and 114 observations for abundance), AEM significantly increased species richness and their abundance. More specifically, we test the hypothesis that AEM benefits species richness and abundance (i.e. increases the difference between fields with and without AEM) more in simple than in complex landscapes. In croplands, species richness but not abundance was significantly enhanced in simple but not in complex landscapes. In grasslands, AEM effectively enhanced species richness and abundance regardless of landscape context. Pollinators were significantly enhanced by AEM in simple but not in complex landscapes in both croplands and grasslands. Our results highlight that the one-size-fits-all approach of many agri-environmental programmes is not an efficient way of spending the limited funds available for biodiversity conservation on farmland. Therefore, we conclude that AEM should be adapted to landscape structure and the species groups at which they are targeted.
Changing environmental characteristics of European cropland
Bakker, M.M. ; Hatna, E. ; Kuhlman, T. ; Mücher, C.A. - \ 2011
Agricultural Systems 104 (2011)7. - ISSN 0308-521X - p. 522 - 532.
agricultural land-use - cover change - future - areas - roads
The spatial configuration of agricultural systems is continuously changing in response to changes in demand for agricultural goods, changes in the level of competition between different land use activities, and progress in agricultural technology. This may lead to a change in the location of agricultural systems and consequently to a change in their average environmental characteristics. This paper explores the change in environmental characteristics of cropland (horticulture and field crops) over the years 1950, 1990 and 2000, for Western and Eastern Europe, using basic descriptive statistics. Underlying mechanisms are explored with logistic (interaction) regression analysis. We find that in both Eastern and Western Europe, crop cultivation shifted away from cities. In Western Europe cropland became situated on shallower soils, steeper slopes, and drier and less accessible areas. Probable reasons are that technical progress reduced the importance of traditional constraints such as drought, poor soils, and distance from markets, so that crop farmers were allowed to move to warm and sunny areas where potential productivity is highest. In addition, cropland probably lost some of its competitive power to grassland and nature. In Eastern Europe cropland concentrated on deeper soils and flatter terrain from 1990 onward. Here, the abandonment of the central planning system and a more flexible land market must have allowed a shift of cropland towards more suitable locations.
Simulation modelling and risk assessment as tools to identify the impact of climate change on microbiological food safety – The case study of fresh produce supply chain
Jacxsens, L. ; Luning, P.A. ; Vorst, J.G.A.J. van der; Devlieghere, F. ; Leemans, R. ; Uyttendaele, M. - \ 2010
Food Research International 43 (2010)7. - ISSN 0963-9969 - p. 1925 - 1935.
minimally processed vegetables - escherichia-coli o157-h7 - agricultural land-use - time rt-pcr - ambient-temperature - iceberg lettuce - cryptosporidium oocysts - foodborne pathogens - contaminated water - future scenarios
The current quality assurance and control tools and methods to prevent and/or to control microbiological risks associated with fresh produce are challenged due to the following pressures upon the food supply chain, i.e. changing consumption patterns, globalization and climate change. It demonstrates the need for scientific research and development of new and/or improved tools, techniques and practices to adapt the current risk management systems. In this paper, a conceptual research approach is presented to analyse the complexity of the climate change and globalization challenge on the fresh produce supply chain taken as a case study. The factors which affect the vulnerability of the fresh produce chain demand a multidisciplinary research approach. The proposed knowledge-based modelling system is believed to be a most appropriate way to identify problems and to offer solutions to monitor and prevent microbiological food safety risks during all phases of food production and supply. To explore the potential impact of climate change and globalization, baseline information can be obtained by surveillance and performance measurement of implemented food safety management systems. Simulation of climate change scenarios and the logistic chain of fresh produce, along with mathematical models to optimize packaging technology to maintain quality and safety of fresh produce are tools to provide insights in the complex dynamic ecosystem. They are the basis for elaboration of risk assessment studies to scientifically support management options and decisions to new microbiological threats related to globalization and climate change in the fresh produce supply chain. This research concept as such will contribute to develop strategies in order to guarantee the (microbiological) food safety of fresh produce on the long term
Vulnerability and adaptation of European farmer: a multi-level analysis of yield and income responses to climate variability
Reidsma, P. ; Ewert, F. ; Oude Lansink, A.G.J.M. ; Leemans, R. - \ 2009
Regional Environmental Change 9 (2009)1. - ISSN 1436-3798 - p. 25 - 40.
agricultural land-use - crop models - adaptive capacity - food-production - elevated co2 - impacts - policy - wheat - trends - heterogeneity
Climate change will affect crop yields and consequently farmers¿ income. The underlying relationships are not well understood, particularly the importance of crop management and related factors at the farm and regional level. We analyze the impacts of trends and variability in climatic conditions from 1990 to 2003 on trends and variability in yields of five crops and farmers¿ income at farm type and regional level in Europe considering farm characteristics and other factors. While Mediterranean regions are often characterized as most vulnerable to climate change, our data suggest effective adaptation to variable and changing conditions in these regions largely attributable to the characteristic farm types in these regions. We conclude that for projections of climate change impacts on agriculture, farm characteristics influencing management and adaptation should be considered, as they largely influence the potential impacts
Sugarcane for Bioethanol: Soil and Environmental Issues
Hartemink, A.E. - \ 2008
Advances in Agronomy 99 (2008). - ISSN 0065-2113 - p. 125 - 182.
papua-new-guinea - nonpoint-source pollution - greenhouse-gas emissions - organic-matter content - agricultural land-use - great-barrier-reef - nitrogen-fixation - south-africa - precision agriculture - north queensland
Cultivation of sugarcane for bioethanol is increasing and the area under sugarcane is expanding. Much of the sugar for bioethanol comes from large plantations where it is grown with relatively high inputs. Sugarcane puts a high demands on the soil because of the use of heavy machinery and because large amounts of nutrients are removed with the harvest; biocides and inorganic fertilizers introduce risks of groundwater contamination, eutrophication of surface waters, soil pollution, and acidification. This chapter reviews the effect of commercial sugarcane production on soil chemical, physical, and biological properties using data from the main producing areas. Although variation is considerable, soil organic C decreased in most soils under sugarcane and, also, soil acidification is common as a result of the use of N fertilizers. Increased bulk densities, lower water infiltration rates, and lower aggregate stability occur in mechanized systems. There is some evidence for high leaching losses of fertilizer nutrients as well as herbicides and pesticides; eutrophication of surface waters occurs in high-input systems. Soil erosion is a problem on newly planted land in many parts of the world. Trash or green harvesting overcomes many of the problems. It is concluded that sugarcane cultivation can substantially contribute to the supply of renewable energy, but that improved crop husbandry and precision farming principles are needed to sustain and improve the resource base on which production depends
Sectoral approaches to improve regional carbon budgets
Smith, P. ; Nabuurs, G.J. ; Janssens, I.A. ; Reis, S. ; Marland, G. ; Soussana, J.F. ; Christensen, T.R. ; Heath, L. ; Apps, M. ; Alexeyev, V. ; Fang, J. ; Gattuso, J.P. ; Guerschman, J.P. ; Huang, Y. ; Jobbagy, E. ; Murdiyarso, D. ; Ni, J. ; Nobre, A. ; Peng, C. ; Walcroft, A. ; Wang, S.Q. ; Pan, Y. ; Zhou, G.S. - \ 2008
Climatic Change 88 (2008)3-4. - ISSN 0165-0009 - p. 209 - 249.
soil organic-matter - net primary production - agricultural land-use - long-term experiments - conterminous united-states - northern hardwood forests - nitrous-oxide emissions - peat bog growth - climate-change - european forests
Humans utilise about 40% of the earth¿s net primary production (NPP) but the products of this NPP are often managed by different sectors, with timber and forest products managed by the forestry sector and food and fibre products from croplands and grasslands managed by the agricultural sector. Other significant anthropogenic impacts on the global carbon cycle include human utilization of fossil fuels and impacts on less intensively managed systems such as peatlands, wetlands and permafrost. A great deal of knowledge, expertise and data is available within each sector. We describe the contribution of sectoral carbon budgets to our understanding of the global carbon cycle. Whilst many sectors exhibit similarities for carbon budgeting, some key differences arise due to differences in goods and services provided, ecology, management practices used, land-management personnel responsible, policies affecting land management, data types and availability, and the drivers of change. We review the methods and data sources available for assessing sectoral carbon budgets, and describe some of key data limitations and uncertainties for each sector in different regions of the world. We identify the main gaps in our knowledge/data, show that coverage is better for the developed world for most sectors, and suggest how sectoral carbon budgets could be improved in the future. Research priorities include the development of shared protocols through site networks, a move to full carbon accounting within sectors, and the assessment of full greenhouse gas budgets
Factors affecting soil quality changes in the North China Plain: a case study of Quzhou County
Chen, J. ; Yu, Z. ; Ouyang, J. ; Mensvoort, M.E.F. van - \ 2006
Agricultural Systems 91 (2006)3. - ISSN 0308-521X - p. 171 - 188.
agricultural land-use - of-the-art - nutrient balances - indicators - management - africa - flows - policies - scales - farm
At the end of the 1970s there were 3,300,000 ha of salt-affected land in the North China Plain. After the successful removal of the salt in the 1980s, the land has gradually been used for increasing intensive forms of agriculture. The Household Responsibility System (HRS) was adopted in Chinese rural areas at the time of the economic reform of the early 1980s. Farm households became the basic decision-making units that could directly control soil quality. This paper describes the change in soil fertility after 20 years of intensive agriculture and the driving factors of soil fertility change. Quzhou County was selected as it is representative for the North China Plain. The soil fertility status and nutrient flows of the salt-affected land for 1980¿1981 and 1999 in Quzhou County were evaluated. Over 20 years, the total nitrogen (N), the extractable phosphorus (P) and the soil organic matter (SOM) in salt-affected land increased by 127%, 601% and 51% respectively; but exchangeable potassium decreased by 31%. The N, P, K and SOM balance in 1980¿1981 was ¿15, ¿2, ¿29 and ¿24 kg ha¿1 y¿1, but in 1999 the N and P balance had changed to 24 kg ha¿1 y¿1 and 25 kg ha¿1 y¿1 as a result of the widespread use of N and P fertilizer. With the rapid increase in crop production and the sparse use of K fertilizer, the K balance continues to be negative. Straw production increased along with crop yields and there was a development of stock breeding. Together with better straw restitution practices, the SOM balance increased to a positive 613 kg ha¿1 y¿1. The analysis of farm household land-use and inputs indicated that there were significant differences in behaviour between almost totally off-farm households and other household types. These differences were in the choice of land-use type, the use of fertilizers and crop residue management. However, there was no significant relationship between socio-economic factors and fertilizer inputs. Current nutrient management is not optimal. Therefore, it is important to establish a better system for bottom-up knowledge collection and transfer of scientific information to farmers.
Projected changes in mineral soil carbon of European croplands and grasslands, 1990-2080
Smith, J. ; Smith, P. ; Wattenbach, M. ; Zaehle, S. ; Hiederer, R. ; Jones, R.J.A. ; Montanarella, L. ; Rounsevell, M.D.A. ; Reginster, I. ; Ewert, F. - \ 2005
Global Change Biology 11 (2005)12. - ISSN 1354-1013 - p. 2141 - 2152.
long-term experiments - agricultural land-use - organic-carbon - climate-change - terrestrial carbon - future scenarios - regional-scale - co2 emissions - model - sequestration
We present the most comprehensive pan-European assessment of future changes in cropland and grassland soil organic carbon (SOC) stocks to date, using a dedicated process-based SOC model and state-of-the-art databases of soil, climate change, land-use change and technology change. Soil carbon change was calculated using the Rothamsted carbon model on a European 10 × 10' grid using climate data from four global climate models implementing four Intergovernmental Panel on Climate Change (IPCC) emissions scenarios (SRES). Changes in net primary production (NPP) were calculated by the Lund¿Potsdam¿Jena model. Land-use change scenarios, interpreted from the narratives of the IPCC SRES story lines, were used to project changes in cropland and grassland areas. Projections for 1990¿2080 are presented for mineral soil only. Climate effects (soil temperature and moisture) will tend to speed decomposition and cause soil carbon stocks to decrease, whereas increases in carbon input because of increasing NPP will slow the loss. Technological improvement may further increase carbon inputs to the soil. Changes in cropland and grassland areas will further affect the total soil carbon stock of European croplands and grasslands. While climate change will be a key driver of change in soil carbon over the 21st Century, changes in technology and land-use change are estimated to have very significant effects. When incorporating all factors, cropland and grassland soils show a small increase in soil carbon on a per area basis under future climate (1¿7 t C ha1 for cropland and 3¿6 t C ha1 for grassland), but when the greatly decreasing area of cropland and grassland are accounted for, total European cropland stocks decline in all scenarios, and grassland stocks decline in all but one scenario. Different trends are seen in different regions. For Europe (the EU25 plus Norway and Switzerland), the cropland SOC stock decreases from 11 Pg in 1990 by 4¿6 Pg (39¿54%) by 2080, and the grassland SOC stock increases from 6 Pg in 1990 to 1.5 Pg (25%) under the B1 scenario, but decreases to 1¿3 Pg (20¿44%) under the other scenarios. Uncertainty associated with the land-use and technology scenarios remains unquantified, but worst-case quantified uncertainties are 22.5% for croplands and 16% for grasslands, equivalent to potential errors of 2.5 and 1 Pg SOC, respectively. This is equivalent to 42¿63% of the predicted SOC stock change for croplands and 33¿100% of the predicted SOC stock change for grasslands. Implications for accounting for SOC changes under the Kyoto Protocol are discussed.
ROTAT, a tool for systematically generating crop rotations
Dogliotti Moro, S. ; Rossing, W.A.H. ; Ittersum, M.K. van - \ 2003
European Journal of Agronomy 19 (2003). - ISSN 1161-0301 - p. 239 - 250.
agricultural land-use - systems - sustainability - netherlands - management - options - models
This paper reports part of a methodology for a model-based exploration of land use motivated by the lack of sustainability of small farming systems in southern Uruguay. Explorative land use studies aim to gain insight into future possibilities for agricultural development. They support strategic thinking during the design of new farming systems. The crop rotation plays a central role in a farming system and represents a logical starting point in the design process. The combination and sequence of crop species determine characteristics of farming systems such as crop yields, soil erosion, occurrence of soil-borne pests, diseases and weeds, and dynamics of nitrogen and labour. Here, we present a software tool called ROTAT, designed for generating crop rotations based on agronomic criteria in a transparent manner. The program combines crops from a predefined list to generate all possible rotations. The full factorial number of possible combinations of crops is limited by a number of filters controlled by the user. These filters are designed to eliminate crop successions which are agronomically unfeasible and for farm-specific reasons not practical or desirable. The filters represent expert knowledge in a quantitative and explicit way. The use of this computer program as a stand-alone tool in the process of designing crop rotations is illustrated with a published case study from an ecological pilot farm in Flevoland (The Netherlands). Using this software we were able to design 840 rotations based on the same crops and designing criteria that were used for the example farm. Many of these rotations might be interesting alternatives to the one actually implemented. Coupled with a sound procedure to evaluate the performance of such a large number of rotations 'a priori', ROTAT can reduce the risk of ignoring promising options and the arbitrariness present in previous studies dealing with design of rotations. The usefulness Of ROTAT for designing production activities in explorative land use studies based on linear programming is discussed. (C) 2002 Elsevier Science B.V. All rights reserved.