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基于能值理论分析方法的农业灌溉效益研究 被引量:6
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作者 罗乾 方国华 +1 位作者 黄显峰 闫轲 《水电能源科学》 北大核心 2011年第6期137-139,共3页
针对传统方法计算农业灌溉效益时无法衡量自然环境对农作物生产影响的缺陷,以连云港市农作物生产系统为例,采用能值理论及其统一衡量标准将决定灌溉效益的主要指标转化为同一量纲,定义了灌溉效益分摊系数,构建了农业灌溉效益能值指标体... 针对传统方法计算农业灌溉效益时无法衡量自然环境对农作物生产影响的缺陷,以连云港市农作物生产系统为例,采用能值理论及其统一衡量标准将决定灌溉效益的主要指标转化为同一量纲,定义了灌溉效益分摊系数,构建了农业灌溉效益能值指标体系并分析了影响因素,为灌溉效益准确计算提出了具体方案。 展开更多
关键词 能值理论 农业灌溉效益 灌溉效益分摊系数 农作物生产系统
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能值法计算农业灌溉效益分摊系数 被引量:2
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作者 罗乾 魏广平 《水利科技与经济》 2011年第6期61-63,共3页
应用能值理论及其统一的衡量标准,将决定灌溉效益分摊系数的主要指标——灌溉用水量与灌溉设施投入转化为同一的量纲,可克服传统方法计算农业灌溉效益分摊系数时,无法衡量自然环境对农作物生产影响的缺陷,定义农业灌溉总能值投入量和生... 应用能值理论及其统一的衡量标准,将决定灌溉效益分摊系数的主要指标——灌溉用水量与灌溉设施投入转化为同一的量纲,可克服传统方法计算农业灌溉效益分摊系数时,无法衡量自然环境对农作物生产影响的缺陷,定义农业灌溉总能值投入量和生产过程总能值投入量的比值为效益分摊系数,为农业灌溉效益的准确计算提出具体的方法。 展开更多
关键词 能值 灌溉效益分摊系数 农作物生产系统
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Construction and Realization of Decision Support System on Production Plan of Regional Crops
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作者 Jie YUAN 《Agricultural Science & Technology》 CAS 2012年第6期1381-1384,共4页
Based on low income of farmers and blindness of crop production,decision support system on production plan of regional crops was proposed with consideration of clustering production,low harvest with high yield,histori... Based on low income of farmers and blindness of crop production,decision support system on production plan of regional crops was proposed with consideration of clustering production,low harvest with high yield,historical data and market information using statistics and mathematical modeling. 展开更多
关键词 Information system Crop production Decision support
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Mitigating greenhouse gas of chemical fertilizer with farmland emissions through replacement organic manure in a temperate 被引量:13
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作者 Haitao Liu Jing Li +3 位作者 Xiao Li Yanhai Zheng Sufei Feng Gaoming Jiang 《Science Bulletin》 SCIE EI CAS CSCD 2015年第6期598-606,M0003,共10页
Burning crop residues and excessive use of chemical fertilizers results in an enormous waste of bio- logical resources, which further weakens the potential capacity of the agro-ecosystem as a carbon sink. To explore t... Burning crop residues and excessive use of chemical fertilizers results in an enormous waste of bio- logical resources, which further weakens the potential capacity of the agro-ecosystem as a carbon sink. To explore the potential of farmlands acting as a carbon sink without yield losses, we conducted an experiment on a temperate eco-farm in eastern rural China. Crop residues were applied to cattle feed, and the composted cattle manure was returned to cropland with a winter wheat and maize rotation. Four different proportions of fertilizers were designed: 100 % cattle manure, 100 % mineral nitrogen, 75 % cattle manure plus 25 % mineral nitrogen, and 50 % cattle manure plus 50 % mineral nitrogen. Crop yield and greenhouse gas (GHG) emissions were carefully calculated according to the Intergovernmental Panel on Climate Change (IPCC) Guidelines for National Green- house Gas Inventories 2006. Our results showed that replacing chemical fertilizer with organic manure signifi- cantly decreased the emission of GHGs. Yields of wheat and corn also increased as the soil fertility was improved by the application of cattle manure. Totally replacing chemical fertilizer with organic manure decreased GHG emissions, which reversed the agriculture ecosystem from a carbon source (+2.7 t CO_2-eq. hm-2 year-1) to a carbon sink (-8.8 t CO_2-eq. hm^-2 year^-1). Our findings provide useful insights for improving agricultural ecosystems under global change scenarios. 展开更多
关键词 Crop residue Chemical fertilizer Cattle manure Crop yield Greenhouse gasemissions Climate change
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