由于传统Wackernagel and Rees生态足迹模型仅研究人类对资源的需求和生态系统供给的生物生产能力之间的差距,忽略了生态系统的其它功能,无法体现生态系统的整体性。本文以传统生态足迹模型为基础,引入生态系统服务功能价值理论,提出了...由于传统Wackernagel and Rees生态足迹模型仅研究人类对资源的需求和生态系统供给的生物生产能力之间的差距,忽略了生态系统的其它功能,无法体现生态系统的整体性。本文以传统生态足迹模型为基础,引入生态系统服务功能价值理论,提出了基于生态系统服务功能价值的生态足迹模型。该模型以生态生产性土地的生态服务功能价值评估为基础,改进传统生态足迹模型中均衡因子和产量因子的计算方法。采用生物生产性土地的综合生态系统服务功能的价值当量因子计量生态足迹模型中的均衡因子,采用生态系统单元的单位面积生态系统服务功能价值与全国该生态系统单元的平均价值的比值表示产量因子。改进后的生态足迹模型既反映了区域人类资源消费对生物生产性土地的占用,又反映了区域人类资源消费对生态系统服务功能的使用,较科学的体现了生态系统的整体性。同时,本文以大连市2005年社会经济统计数据为基础,运用改进的生态足迹模型对大连市的生态足迹进行了测算,对研究模型进行了检验。展开更多
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
Sanjiangyuan is an extremely important biodiversity-conservation area with notable worldwide ecological significance. However, due to global climate change and increased human activities, the natural environment in th...Sanjiangyuan is an extremely important biodiversity-conservation area with notable worldwide ecological significance. However, due to global climate change and increased human activities, the natural environment in this region has undergone major alterations. In this work, we used the InVEST model to assess the spatial and temporal distribution of habitat quality and habitat degradation in the Sanjiangyuan region from 2000 to 2020. CA-Markov model was used to predict the land use changes under “natural development”(ND) and “ecological protection”(EP) scenarios from 2025 to 2050, and a comparative analysis of land use and habitat-quality changes was made in combination with the results of ecological zoning planning. We found that changes in human use land and bare land directly affect changes in habitat quality in Sanjiangyuan and are a major threat to habitat quality. Using the human-footprint index, Sanjiangyuan was divided into key protected areas, key restoration areas, and moderately developed areas. We compared the changes in habitat quality under two scenarios and discovered that under the EP scenario, the region of high habitat quality expanded, indicating that the EP scenario is beneficial for the sustainable development and conservation of biodiversity in Sanjiangyuan.展开更多
目的:非正常足型的发展会对儿童的生长和生活带来不利的影响,儿童非正常足型的早期诊断有利于对儿童足型的及时矫正。文章对文献中儿童足型分类的方法进行总结与回顾,以期为临床医生在儿童非正常足型的预防与矫正策略的研究上提供有价...目的:非正常足型的发展会对儿童的生长和生活带来不利的影响,儿童非正常足型的早期诊断有利于对儿童足型的及时矫正。文章对文献中儿童足型分类的方法进行总结与回顾,以期为临床医生在儿童非正常足型的预防与矫正策略的研究上提供有价值的参考信息。方法:在万方、维普、中国知网、Web of Science和PubMed数据库中对儿童足型分类的相关文献进行检索,并对儿童足型分类的方法进行分类、归纳与系统评价。结果:(1)最终纳入12篇文献,其中儿童足型分类方法主要包括足印指数法、放射学评估法、临床检查法和人体测量学检查法共4种;(2)各种分类方法的优缺点:足印法简单快捷,但测量结果具有片面性;放射学评估法具有潜在的辐射风险,且成本高、流程复杂;临床检查法虽快捷、成本低,但具有较强的主观性;人体测量学检查法虽然较为准确,但耗时较长;(3)在以往研究中,研究人员大多数选择经济快捷的足印法作为儿童足型的分类方法,且部分研究采用多种指标相结合的方式以提高儿童足型分类的准确性;(4)目前较为准确的儿童足型的分类方法就是采用多种指标相结合的方式。结论:目前儿童足型的分类缺乏金标准,多数足型分类方法仅显示足部静态的结构特征,未来的研究需建立静态足部结构和动态足部功能之间的关系,以增加儿童足型分类结果的准确性和科学性,从而在儿童骨骺闭合年龄结束前对儿童足部的健康成长和发育提供良好的策略。展开更多
文摘由于传统Wackernagel and Rees生态足迹模型仅研究人类对资源的需求和生态系统供给的生物生产能力之间的差距,忽略了生态系统的其它功能,无法体现生态系统的整体性。本文以传统生态足迹模型为基础,引入生态系统服务功能价值理论,提出了基于生态系统服务功能价值的生态足迹模型。该模型以生态生产性土地的生态服务功能价值评估为基础,改进传统生态足迹模型中均衡因子和产量因子的计算方法。采用生物生产性土地的综合生态系统服务功能的价值当量因子计量生态足迹模型中的均衡因子,采用生态系统单元的单位面积生态系统服务功能价值与全国该生态系统单元的平均价值的比值表示产量因子。改进后的生态足迹模型既反映了区域人类资源消费对生物生产性土地的占用,又反映了区域人类资源消费对生态系统服务功能的使用,较科学的体现了生态系统的整体性。同时,本文以大连市2005年社会经济统计数据为基础,运用改进的生态足迹模型对大连市的生态足迹进行了测算,对研究模型进行了检验。
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.
文摘Sanjiangyuan is an extremely important biodiversity-conservation area with notable worldwide ecological significance. However, due to global climate change and increased human activities, the natural environment in this region has undergone major alterations. In this work, we used the InVEST model to assess the spatial and temporal distribution of habitat quality and habitat degradation in the Sanjiangyuan region from 2000 to 2020. CA-Markov model was used to predict the land use changes under “natural development”(ND) and “ecological protection”(EP) scenarios from 2025 to 2050, and a comparative analysis of land use and habitat-quality changes was made in combination with the results of ecological zoning planning. We found that changes in human use land and bare land directly affect changes in habitat quality in Sanjiangyuan and are a major threat to habitat quality. Using the human-footprint index, Sanjiangyuan was divided into key protected areas, key restoration areas, and moderately developed areas. We compared the changes in habitat quality under two scenarios and discovered that under the EP scenario, the region of high habitat quality expanded, indicating that the EP scenario is beneficial for the sustainable development and conservation of biodiversity in Sanjiangyuan.
文摘目的:非正常足型的发展会对儿童的生长和生活带来不利的影响,儿童非正常足型的早期诊断有利于对儿童足型的及时矫正。文章对文献中儿童足型分类的方法进行总结与回顾,以期为临床医生在儿童非正常足型的预防与矫正策略的研究上提供有价值的参考信息。方法:在万方、维普、中国知网、Web of Science和PubMed数据库中对儿童足型分类的相关文献进行检索,并对儿童足型分类的方法进行分类、归纳与系统评价。结果:(1)最终纳入12篇文献,其中儿童足型分类方法主要包括足印指数法、放射学评估法、临床检查法和人体测量学检查法共4种;(2)各种分类方法的优缺点:足印法简单快捷,但测量结果具有片面性;放射学评估法具有潜在的辐射风险,且成本高、流程复杂;临床检查法虽快捷、成本低,但具有较强的主观性;人体测量学检查法虽然较为准确,但耗时较长;(3)在以往研究中,研究人员大多数选择经济快捷的足印法作为儿童足型的分类方法,且部分研究采用多种指标相结合的方式以提高儿童足型分类的准确性;(4)目前较为准确的儿童足型的分类方法就是采用多种指标相结合的方式。结论:目前儿童足型的分类缺乏金标准,多数足型分类方法仅显示足部静态的结构特征,未来的研究需建立静态足部结构和动态足部功能之间的关系,以增加儿童足型分类结果的准确性和科学性,从而在儿童骨骺闭合年龄结束前对儿童足部的健康成长和发育提供良好的策略。
