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How Could Agricultural Land Systems Contribute to Raise Food Production Under Global Change? 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
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Prince Chinedu Peter 《Communications in Soil Science and Plant Analysis》2018,49(3):389-403
Degrading soil quality and productivity are major global challenges exacerbated by climate change and management practices. The dwindling global economy calls for other cost-effective approaches to address these challenges. This study reviewed a number of literatures on degraded soils, conservation agriculture (CA), and biochar soil amendment. The aim is to establish a base for more appropriate policy decisions and support for research on CA and biochar soil amendment nexus, which will enable the design of profitable and sustainable farming systems. Studies have highlighted the positive effects of CA practice, yet the adoption is low and some shortfalls have been reported. Likewise in the application of biochar as soil amendment, positive soil transformations have been recorded and some lapses. It is therefore imperative to explore the possibility of merging the two practices to see if the effects are complimentary, additive, or opposing in which case the positive values could be lost. 相似文献
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Peter Oko Ogbaji Jianmin Li Xuzhang Xue Mohamad Hesam Shahrajabian Anthony Egrinya Eneji 《Communications in Soil Science and Plant Analysis》2018,49(3):286-290
Studies were conducted to investigate mineralogical and textural characteristics of Hancheng soils in relation to fertility status, mineralogical, and particle size distribution properties, which were determined from soil samples of the profile pits in 2014. Prepared representative clay fraction samples were subjected to x-ray diffraction analysis for mineralogical characterization. The results show dominant of quartz, attributed to high granitic parent materials with a range of 65.7–84.6% mean 54.1%, moganite 59.8%, albite 12.0–26.3% mean 21.03%, flusston 18.1%, calcium magnesium silicate 10.6%, muscovite 7.8%, olivine 1.8%, and illite 1.6% were detected. The particle size distribution analysis revealed sand fraction of 28.12–30.12% mean 29.1%, 22.12–28.12% mean 25.1%; silt 34.0–36.0% mean 35%, 32.0–38.0% mean 35%; and clay 35.9–35.9% mean 35.9%, 35.9–43.9% mean 32.6% surface and subsurface soils respectively. Texture classes of the soils were clay loam to clay apredominantly clay loam. The mineralogical and textural characteristics are important in relation to soil fertility, which allow farmers to adapt crop management practices with real soil situation. 相似文献
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Peter A Robertson Tim Adriaens Xavier Lambin Aileen Mill Sugoto Roy Craig M Shuttleworth Mike Sutton‐Croft 《Pest management science》2017,73(2):273-279
Numerous examples exist of successful mammalian invasive alien species (IAS) eradications from small islands (<10 km2), but few from more extensive areas. We review 15 large‐scale removals (mean area 2627 km2) from Northern Europe since 1900, including edible dormouse, muskrat, coypu, Himalayan porcupine, Pallas' and grey squirrels and American mink, each primarily based on daily checking of static traps. Objectives included true eradication or complete removal to a buffer zone, as distinct from other programmes that involved local control to limit damage or spread. Twelve eradication/removal programmes (80%) were successful. Cost increased with and was best predicted by area, while the cost per unit area decreased; the number of individual animals removed did not add significantly to the model. Doubling the area controlled reduced cost per unit area by 10%, but there was no evidence that cost effectiveness had increased through time. Compared with small islands, larger‐scale programmes followed similar patterns of effort in relation to area. However, they brought challenges when defining boundaries and consequent uncertainties around costs, the definition of their objectives, confirmation of success and different considerations for managing recolonisation. Novel technologies or increased use of volunteers may reduce costs. Rapid response to new incursions is recommended as best practice rather than large‐scale control to reduce the environmental, financial and welfare costs. © 2016 Crown copyright. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献
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Coherent anti‐Stokes Raman scattering (CARS) spectroscopy in Caenorhabditis elegans and Globodera pallida: evidence for an ivermectin‐activated decrease in lipid stores 下载免费PDF全文
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Suzanne Osorio Lujan Walid Habre Youssef Daali Zhaoxin Pan Peter W. Kronen 《Veterinary anaesthesia and analgesia》2017,44(3):665-675