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1.
Combining top-down and bottom-up dynamics in land use modeling: exploring the future of abandoned farmlands in Europe with the Dyna-CLUE model 总被引：9，自引：0，他引：9
Land use change is the result of interactions between processes operating at different scales. Simulation models at regional
to global scales are often incapable of including locally determined processes of land use change. This paper introduces a
modeling approach that integrates demand-driven changes in land area with locally determined conversion processes. The model
is illustrated with an application for European land use. Interactions between changing demands for agricultural land and
vegetation processes leading to the re-growth of (semi-) natural vegetation on abandoned farmland are explicitly addressed.
Succession of natural vegetation is simulated based on the spatial variation in biophysical and management related conditions,
while the dynamics of the agricultural area are determined by a global multi-sector model. The results allow an exploration
of the future dynamics of European land use and landscapes. The model approach is similarly suitable for other regions and
processes where large scale processes interact with local dynamics. 相似文献
2.
Spatio-Temporal Changes in the Rice Planting Area and Their Relationship to Climate Change in Northeast China：A Model-Based Analysis 总被引：3，自引：0，他引：3
XIA Tian ;WU Wen-bin ;ZHOU Qing-bo ;YU Qiang-yi ;Peter H Verburg ;YANG Peng ;LU Zhong-jun ;TANG Hua-jun 《中国农业科学(英文版)》2014,(7):1575-1585
Rice is one of the most important grain crops in Northeast China （NEC） and its cultivation is sensitive to climate change. This study aimed to explore the spatio-temporal changes in the NEC rice planting area over the period of 1980-2010 and to analyze their relationship to climate change. To do so, the CLUE-S （conversion of land use and its effects at small region extent） model was ifrst updated and used to simulate dynamic changes in the rice planting area in NEC to understand spatio-temporal change trends during three periods： 1980-1990, 1990-2000 and 2000-2010. The changing results in individual periods were then linked to climatic variables to investigate the climatic drivers of these changes. Results showed that the NEC rice planting area expanded quickly and increased by nearly 4.5 times during 1980-2010. The concentration of newly planted rice areas in NEC constantly moved northward and the changes were strongly dependent on latitude. This conifrmed that climate change, increases in temperature in particular, greatly inlfuenced the shift in the rice planting area. The shift in the north limit of the NEC rice planting area generally followed a 1＆#176;C isoline migration pattern, but with an obvious time-lag effect. These ifndings can help policy makers and crop producers take proper adaptation measures even when exposed to the global warming situation in NEC. 相似文献
3.
W. W. Miller D. W. Johnson C. Denton P. S. J. Verburg G. L. Dana R. F. Walker 《Water, air, and soil pollution》2005,163(1-4):3-17
It is generally held that surface runoff in heavily forested ecosystems is minimal and therefore nutrient fluxes via runoff are unimportant. This is based in large measure on the absence of direct observation or remnant physical evidence. It is further held that protected forests with heavy understory and litter serve as a nutrient sink due to maximum uptake and interception. Our Sierran studies have detected the presence of surface runoff at several sites in the form of both overland and litter interflow with concentrations of NH4-N as high as 87.2 mg L?1, NO3-N as high as 95.4 mg L?1, and PO4-P as high as 24.4 mg L?1. Data suggest that nutrients are derived from the mature O-horizons, and that there has been little contact with the mineral soil or root zone where strong retention and/or uptake of these ions would be expected. Such contributions from overland/interflow could be particularly important in areas where ultra-oligotrophic lakes (e.g., Lake Tahoe) are now trending towards meso-oligotrophic status. We believe that fire exclusion in these systems may have exacerbated N and P inputs to Lake Tahoe and elsewhere by allowing unnatural buildups of O-horizons that are apparently a source of nutrients to surface runoff. 相似文献
4.
A. Veldkamp K. Kok G. H. J. De Koning J. M. Schoorl M. P. W. Sonneveld P. H. Verburg 《Soil & Tillage Research》2001,58(3-4):129-140
Spatial multi-scale analyses of actual land use system performance as determined by spatial yield variability reveals the need for landscape research in agronomy. Main ‘drivers’ of spatial yield variability for five different crops in Honduras, Costa Rica and Ecuador were identified. It is demonstrated how they vary with spatial scales and that landscape-related factors often play a large and significant role in when the variability in yield is determined. These results indicate that landscape experiments in agronomy are relevant. Apart from empirical analysis, spatial–temporal explicit modeling of landscape process dynamics such as water and soil redistribution within a landscape can give insight in the performance of agronomic systems within a dynamic landscape context. For a case study in the South of Spain it is demonstrated how within a landscape this type of research can determine the on- and off-site effects of water and soil redistribution in agro-ecosystems. Only after a spatially explicit multi-scale system analysis and explorative landscape process modeling is completed, relevant agronomic landscape experiments can be designed. 相似文献
5.
An assessment of the impact of climate adaptation measures to reduce flood risk on ecosystem services 总被引：3，自引：1，他引：2
Peter H. Verburg Eric Koomen Maarten Hilferink Marta Pérez-Soba Jan Peter Lesschen 《Landscape Ecology》2012,27(4):473-486
Measures of climate change adaptation often involve modification of land use and land use planning practices. Such changes in land use affect the provision of various ecosystem goods and services. Therefore, it is likely that adaptation measures may result in synergies and trade-offs between a range of ecosystems goods and services. An integrative land use modelling approach is presented to assess such impacts for the European Union. A reference scenario accounts for current trends in global drivers and includes a number of important policy developments that correspond to on-going changes in European policies. The reference scenario is compared to a policy scenario in which a range of measures is implemented to regulate flood risk and protect soils under conditions of climate change. The impacts of the simulated land use dynamics are assessed for four key indicators of ecosystem service provision: flood risk, carbon sequestration, habitat connectivity and biodiversity. The results indicate a large spatial variation in the consequences of the adaptation measures on the provisioning of ecosystem services. Synergies are frequently observed at the location of the measures itself, whereas trade-offs are found at other locations. Reducing land use intensity in specific parts of the catchment may lead to increased pressure in other regions, resulting in trade-offs. Consequently, when aggregating the results to larger spatial scales the positive and negative impacts may be off-set, indicating the need for detailed spatial assessments. The modelled results indicate that for a careful planning and evaluation of adaptation measures it is needed to consider the trade-offs accounting for the negative effects of a measure at locations distant from the actual measure. Integrated land use modelling can help land use planning in such complex trade-off evaluation by providing evidence on synergies and trade-offs between ecosystem services, different policy fields and societal demands. 相似文献
6.
M F te Pas J W Freriksen A J van Bijnen C L Gerritsen T J van den Bosch F H Harders F J Verburg A H Visscher K H de Greef 《Domestic animal endocrinology》2001,20(3):165-184
Selection for increased growth rate or decreased back fat thickness results in concomitant changes in endocrine and metabolic status. Growth hormone (GH) changes in blood plasma concentration related to selection for growth rate and fat deposition were reported in pigs. The molecular mechanisms regulating selection-induced changes in GH plasma concentration remain largely unknown. We investigated selection-associated changes in GH axis parameters in 2 pig lines selected for increased growth rate (F-line), or decreased back fat thickness (L-line), respectively. First, we investigated selection-associated changes in GH pulse parameters. In both selection lines we found each generation a declining GH peak maximum concentration and area under the GH curve. GH pulse width was not associated with generation number. In both lines generation number was associated with a declined pulse interval, indicating that the number of pulses per day increased on average with 1 pulse per 24 h per generation. Second, plasma concentration of GH axis related Insulin-like growth factor-I (IGF-I) and insulin were investigated. Plasma IGF-I concentration was not associated with generation number in the F-line. Mean plasma insulin concentration declined each generation in both lines. Third, we investigated changes in GH and Pit-1 mRNA levels. In both selection lines GH and Pit-1 mRNA levels increased approximately 50% each generation. The high SD of the GH mRNA levels in both lines may suggest that the GH mRNA levels are pulsatile in vivo. We postulate a molecular mechanism that may explain how selection is associated with increased GH mRNA levels and GH pulse numbers, while lowering GH release per pulse. 相似文献
7.
Water balance information at locations across southern Australia is analysed to identify mechanistic causes for higher water
tables under agricultural systems compared to natural vegetation. Contrasting patterns of water use indicate pronounced physiological
activity in summer by natural ecosystems ensuring the persistence of the dominant perennial species. A strategy of tempered
water use during periods of rainfall excess in winter/spring enables seasonal carryover of soil water to be withdrawn by deep
roots for summer functioning. Characteristic patterns of water use by agricultural systems, comprised mainly of determinant
annual species, are truncated in time but feature elevated peak rates coinciding with periods of maximum soil water availability
during the cooler months. Low seasonal vapour pressure deficit explains the observed benefits of enhanced biomass production
due to high water use efficiency. The associated limited scope for soil water uptake carries the penalty of increased frequency
of drainage and the subsequent resource degradation currently associated with farmland. Inclusion of a perennial lucerne phase
in rotation with crops confers environmental benefit through summer uptake from a rooting depth double that of crops. An effective
buffer is thus provided to restrict drainage under an ensuing cropping phase in a manner that more closely emulates natural
systems. Simulations of phase farming point to a halving in long term drainage. They suggest adoption over a range of arable
land units could cause local retreat of water tables by 0.3 m y−1 initially, leading to a new equilibrium level which would still remain elevated with respect to that under natural vegetation.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
8.
Evaluation of agricultural ecosystem services in fallowing land based on farmers’ participation and model simulation 总被引：1，自引：0，他引：1
Yen Lan Liu Kang-tsung Chang Jetse Stoorvogel Peter Verburg Chin Hong Sun 《Paddy and Water Environment》2012,10(4):301-310
Fallowing with green fertilizer can benefit agricultural ecosystem services (AES). Farmers in Taiwan do not implement fallow practices and plant green fertilizer because the current subsidy level (46,000 NT$ per ha) is too low to manage fallowing. This paper defines the objective of government agriculture policy or the farmer’s objective as maximization of farm productivity, approximated to the value of social welfare and AES. Farms, which do not follow proper fallowing practices, often have poorly maintained fallow land or left farmland abandoned. This results in negative environmental consequences such as cutworm infestations in abandoned land, which in turn can affect crops in adjacent farmlands. The objectives of this study are twofold. First, it determines the proper fallowing subsidy based on the concept of payment for ecosystem services to entice more farmers to participate in fallowing. Second, it simulates the benefit of planting green manure in fallow land to the supply of AES based on the rate of farmers who are willing to participate in fallow land practices and essential parameters that can affect soil fertility change. The approach involves a series of interviews and a developed empirical model. The value of AES when the rate of farmer participation is 100% represents a 1.5% increase in AES (448,317,000 NT$) over the value at the current participation rate of 14%. This study further concludes that the appropriate fallowing subsidy has a large positive impact on AES and social welfare (e.g., benefit from food and biofuel supplies) and is seen as a basis of ecological governance for sustainable agro-ecosystems. 相似文献
9.
How Could Agricultural Land Systems Contribute to Raise Food Production Under Global Change? 
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下载免费PDF全文 WU Wen-bin YU Qiang-yi Verburg H Peter YOU Liang-zhi YANG Peng TANG Hua-jun 《农业科学学报》2014,13(7):1432-1442
To feed the increasing world population, more food needs to be produced from agricultural land systems. Solutions to produce more food with fewer resources while minimizing adverse environmental and ecological consequences require sustainable agricultural land use practices as supplementary to advanced biotechnology and agronomy. This review paper, from a land system perspective, systematically proposed and analyzed three interactive strategies that could possibly raise future food production under global change. By reviewing the current literatures, we suggest that cropland expansion is less possible amid fierce land competition, and it is likely to do less in increasing food production. Moreover, properly allocating crops in space and time is a practical way to ensure food production. Climate change, dietary shifts, and other socio-economic drivers, which would shape the demand and supply side of food systems, should be taken into consideration during the decision-making on rational land management in respect of sustainable crop choice and allocation. And finally, crop-specific agricultural intensification would play a bigger role in raising future food production either by increasing the yield per unit area of individual crops or by increasing the number of crops sown on a particular area of land. Yet, only when it is done sustainably is this a much more effective strategy to maximize food production by closing yield and harvest gaps. 相似文献
10.
Interpretation of Climate Change and Agricultural Adaptations by Local Household Farmers: a Case Study at Bin County,Northeast China 下载免费PDF全文
下载免费PDF全文 YU Qiang-yi WU Wen-bin LIU Zhen-huan Peter H Verburg XIA Tian YANG Peng LU Zhongjun YOU Liang-zhi TANG Hua-jun 《农业科学学报》2014,13(7):1599-1608
Although climate change impacts and agricultural adaptations have been studied extensively, how smallholder farmers perceive climate change and adapt their agricultural activities is poorly understood. Survey-based data (presents farmers' personal perceptions and adaptations to climate change) associated with external biophysical-socioeconomic data (presents real-world climate change) were used to develop a farmer-centered framework to explore climate change impacts and agricultural adaptations at a local level. A case study at Bin County (1980s–2010s), Northeast China, suggested that increased annual average temperature (0.6°C per decade) and decreased annual precipitation (46 mm per decade, both from meteorological datasets) were correctly perceived by 76 and 66.9%, respectively, of farmers from the survey, and that a longer growing season was confirmed by 70% of them. These reasonably correct perceptions enabled local farmers to make appropriate adaptations to cope with climate change: Longer season alternative varieties were found for maize and rice, which led to a significant yield increase for both crops. The longer season also affected crop choice: More farmers selected maize instead of soybean, as implicated from survey results by a large increase in the maize growing area. Comparing warming-related factors, we found that precipitation and agricultural disasters were the least likely causes for farmers' agricultural decisions. As a result, crop and variety selection, rather than disaster prevention and infrastructure improvement, was the most common ways for farmers to adapt to the notable warming trend in the study region. 相似文献