Based on the theory of emergy analysis,a modified model of ecological footprint accounting,termed emergetic ecological footprint(EMEF)in contrast to the conventional ecological footprint(EF)model,is formulated and app...Based on the theory of emergy analysis,a modified model of ecological footprint accounting,termed emergetic ecological footprint(EMEF)in contrast to the conventional ecological footprint(EF)model,is formulated and applied to a case study of Jiangsu cropland,China.Comparisons between the EF and the EMEF with respect to grain,cotton,and food oil were outlined.Per capita EF and EMEF of cropland were also presented to depict the resources consumption level by comparing the biocapacity(BC)or emergetic biocapacity(EMBC,a new BC calculation by emergy analysis) of the same area.In the meanwhile,the ecological sustainability index(ESI),a new concept initiated by the authors, was established in the modified model to indicate and compare the sustainability of cropland use at different levels and between different regions.The results from conventional EF showed that per capita EF of the cropland has exceeded its per capita BC in Jiangsu since 1986.In contrast,based on the EMBC,the per capita EMEF exceeded the per capita EMBC 5 years earlier.The ESIs of Jiangsu cropland use were between 0.7 and 0.4 by the conventional method,while the numbers were between 0.7 and 0.3 by the modified one.The fact that the results of the two methods were similar showed that the modified model was reasonable and feasible,although some principles of the EF and EMEF were quite different. Also,according to the realities of Jiangsu cropland use,the results from the modified model were more acceptable.展开更多
The Ecological Footprint(EF) equation provides useful accounting to analyze the relationship between human activities and the environment.Knowledge of the specific forces driving EF is not fully understood but the STI...The Ecological Footprint(EF) equation provides useful accounting to analyze the relationship between human activities and the environment.Knowledge of the specific forces driving EF is not fully understood but the STIRPAT model provides a simple framework for decomposing the impact of human activities on environment.We applied the EF model in Sichuan Province,China to assess the impact of human activities.The per capita EF increased by 2 fold in the 14 years between 1995 and 2008,but ecological capacity decreased in the same period,suggesting that the biologically productive area of Sichuan Province is inadequate to sustain human activities.According to the refined STIRPAT model,the hypothesized driving forces of EF include population size(P),GDP per capita(A1),quadratic term of GDP per capita(A2),percentage of GDP from industry(T1) and urbanization rate(T2).However,the multi-collinearity among these drivers could be a substantial problem which may reveal negative effect in the final results.Application of the Ridge Regression(RR) method to fit the STIRPAT model had the advantage of being able to avoid the collinearity among independent variables.The results showed that population is the principal driving force of EF variation in Sichuan Province and that urbanization and industrialization also have a positive association with the EF.Analysis of affluence elasticity(EEA) showed that the relationship betweenEF and economic growth was not curvilinear,suggesting that variation of EF does not follow an Environmental Kuznets Curve relative to economic growth in Sichuan Province.展开更多
为改善传统N-Calculator模型的局限性,加强食物氮足迹核算结果与环境影响的联系,提高活性氮管理预见性,将N-Calculator模型与食物系统养分流动(Nutrient Flows in Food Chains,Environment and Resources Use,NUFER)模型进行耦合,以估...为改善传统N-Calculator模型的局限性,加强食物氮足迹核算结果与环境影响的联系,提高活性氮管理预见性,将N-Calculator模型与食物系统养分流动(Nutrient Flows in Food Chains,Environment and Resources Use,NUFER)模型进行耦合,以估算我国2001—2020年人均食物氮足迹,建立组合预测体系。结果显示:2001—2020年,我国人均食物氮足迹由16.04 kg N/a增至18.95 kg N/a;全国食物氮足迹由20.47 Mt N/a增至26.76 Mt N/a;居民饮食结构正由以植物源食物为主的低氮消费模式转向以动物源食物为主的高氮消费模式;食物生产过程产生的活性氮的最终归宿为大气(64.3%)、水体和深层土壤(35.7%);我国食物氮足迹与人均可支配收入、城市化率、动物源食物消费氮占比呈正相关性,与恩格尔系数呈负相关性;未来10 a我国人均食物氮足迹呈增长趋势,预测结果显示年均增幅为0.16 kg N/a。展开更多
基金the National Natural Science Foundation of China(No.40401059)the Natural Science Foundation of the Education Department of Jiangsu Province(No.07KJD170123)the Natural Science Foundation of Nanjing Xiaozhuang University(No.2007NXY06)
文摘Based on the theory of emergy analysis,a modified model of ecological footprint accounting,termed emergetic ecological footprint(EMEF)in contrast to the conventional ecological footprint(EF)model,is formulated and applied to a case study of Jiangsu cropland,China.Comparisons between the EF and the EMEF with respect to grain,cotton,and food oil were outlined.Per capita EF and EMEF of cropland were also presented to depict the resources consumption level by comparing the biocapacity(BC)or emergetic biocapacity(EMBC,a new BC calculation by emergy analysis) of the same area.In the meanwhile,the ecological sustainability index(ESI),a new concept initiated by the authors, was established in the modified model to indicate and compare the sustainability of cropland use at different levels and between different regions.The results from conventional EF showed that per capita EF of the cropland has exceeded its per capita BC in Jiangsu since 1986.In contrast,based on the EMBC,the per capita EMEF exceeded the per capita EMBC 5 years earlier.The ESIs of Jiangsu cropland use were between 0.7 and 0.4 by the conventional method,while the numbers were between 0.7 and 0.3 by the modified one.The fact that the results of the two methods were similar showed that the modified model was reasonable and feasible,although some principles of the EF and EMEF were quite different. Also,according to the realities of Jiangsu cropland use,the results from the modified model were more acceptable.
基金funded by the Knowledge Innovation Project of the Chinese Academy of Sciences(Grant No.KZCX2-YW-333)the National Natural Science Foundation of China(Grant No.40901299)
文摘The Ecological Footprint(EF) equation provides useful accounting to analyze the relationship between human activities and the environment.Knowledge of the specific forces driving EF is not fully understood but the STIRPAT model provides a simple framework for decomposing the impact of human activities on environment.We applied the EF model in Sichuan Province,China to assess the impact of human activities.The per capita EF increased by 2 fold in the 14 years between 1995 and 2008,but ecological capacity decreased in the same period,suggesting that the biologically productive area of Sichuan Province is inadequate to sustain human activities.According to the refined STIRPAT model,the hypothesized driving forces of EF include population size(P),GDP per capita(A1),quadratic term of GDP per capita(A2),percentage of GDP from industry(T1) and urbanization rate(T2).However,the multi-collinearity among these drivers could be a substantial problem which may reveal negative effect in the final results.Application of the Ridge Regression(RR) method to fit the STIRPAT model had the advantage of being able to avoid the collinearity among independent variables.The results showed that population is the principal driving force of EF variation in Sichuan Province and that urbanization and industrialization also have a positive association with the EF.Analysis of affluence elasticity(EEA) showed that the relationship betweenEF and economic growth was not curvilinear,suggesting that variation of EF does not follow an Environmental Kuznets Curve relative to economic growth in Sichuan Province.
文摘为改善传统N-Calculator模型的局限性,加强食物氮足迹核算结果与环境影响的联系,提高活性氮管理预见性,将N-Calculator模型与食物系统养分流动(Nutrient Flows in Food Chains,Environment and Resources Use,NUFER)模型进行耦合,以估算我国2001—2020年人均食物氮足迹,建立组合预测体系。结果显示:2001—2020年,我国人均食物氮足迹由16.04 kg N/a增至18.95 kg N/a;全国食物氮足迹由20.47 Mt N/a增至26.76 Mt N/a;居民饮食结构正由以植物源食物为主的低氮消费模式转向以动物源食物为主的高氮消费模式;食物生产过程产生的活性氮的最终归宿为大气(64.3%)、水体和深层土壤(35.7%);我国食物氮足迹与人均可支配收入、城市化率、动物源食物消费氮占比呈正相关性,与恩格尔系数呈负相关性;未来10 a我国人均食物氮足迹呈增长趋势,预测结果显示年均增幅为0.16 kg N/a。
