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黄淮海平原耕地转移对植被碳储量的影响 总被引:8,自引:0,他引:8
应用GLO-PEM模型和1988年NOAA/AVHRR遥感数据,估算了黄淮海平原植被净初级生产力(NPP),并根据NPP和植被凋落物产生量计算了不同土地利用类型的植被碳密度。通过对1988年与2000年土地利用图的叠置分析,统计了耕地与其他土地利用类型之间的转移量,并估算了耕地转移对植被碳储量的影响。研究发现,耕地转移对植被碳储量变化的影响在不同区域与不同土地利用类型上存在显著差异。1988~2000年间,耕地转移导致全区植被碳储量下降了0.24%,其中耕地转为建设用地是植被碳储量减少的主要原因。这一研究结论为正确把握耕地转移对区域植被碳储量的影响,并据此制订碳汇管理措施具有重要的参考价值。 相似文献
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江西省耕地转移驱动机理 总被引:14,自引:1,他引:14
构建涵盖农业生产、耕地向建设用地转移和耕地向林/草地转移的江西省土地用途转移驱动机理模型,采用分段估计逐步增加解释变量的方法测度了人口、社会、经济、区位和自然因素等驱动土地用途转移的机理。研究表明,人口规模是江西省土地用途转移的重要驱动力,社会经济因素在短时间内起决定性作用,各种驱动力以各种方式组合来增强或者减弱其对区域土地用途转移的作用效果。其中,农业人口规模及生产投入要素是影响江西省农业生产的主要因素;人口规模、平原面积比例及土地管理政策是江西省耕地向建设用地转移过程的重要解释变量;农业人口比重、地形坡度、粮食产量及非农产业是江西省耕地向林/草地转移过程的重要影响因素,并揭示了解释了江西省在众多驱动力作用下土地用途转移规律。 相似文献
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黄淮海平原气候变化及其对耕地生产潜力的影响 总被引:8,自引:0,他引:8
利用1991年和2000年黄淮海平原气象台站的历史观测资料,分析该地区气温、降水的变化趋势,并利用农业生态地带(AEZ)模型估算黄淮海平原各农业生态区的耕地生产潜力。通过分析气温、降水与耕地生产潜力的关系,评价气候变化对耕地生产潜力的影响。研究发现,黄淮海平原耕地生产潜力与降水量、气温呈显著正相关。对各农业生态区的回归分析表明,如果气温或降水量提高10%,耕地生产潜力将分别提高3.2%与0.3%。该研究对制订应对气候变化、保护耕地与提高耕地生产潜力方面的决策具有参考价值。 相似文献
4.
基于空间分析与实证的中国农业土地边际收益与全要素生产率研究(英文) 总被引:1,自引:0,他引:1
This paper attempts to explore the temporal and spatial nature of the marginal revenue of land, total factor productivity (TFP) change and its three components: technical change (TC), technical efficiency change (TEC) and scale efficiency change (SEC) as seen in Chinese agricultural production from 1995 to 1999. Based on county-level data, the study utilized both stochastic frontier and mapping analyses methods. The results show that growth in the marginal revenue of land was diverse across various regions, where most gain occurred in eastern coastal zone, while loss was in Northwest and North China. China has experienced moderate decreases in annual TFP change (-0.26%) with considerable regional variations. Specifically, the administrative intervention in grain production and the deterioration of the agricultural technology diffusion system led to a moderate drop in annual TFP change. County-level mapping analyses took into account interregional variances in TFP and its components. Regarding components of TFP, TEC differences explain the majority of regional dispersions in TFP. As developed areas in China, the Huang-Huai-Hai region and the Beijing-Tianjin-Tangshan economic zone face the challenges of land conversion and grain security amidst the process of urbanization. 相似文献
5.
中国东北地区林地面积变化的动态模拟 总被引:1,自引:0,他引:1
There is plenty of forests in Northeast China which contributes a lot to the conservation of water and land resources, produces timber products, and provides habitats for a huge number of wild animals and plants. With changes of socio-economic factors as well as the geophysical conditions, there are dramatic changes on the spatial patterns of forest area. In this sense, it is of great significance to shed light on the dynamics of forest area changes to find the underlining reasons for shaping the changing patterns of forest area in Northeast China. To explore the dynamics of forest area change in Northeast China, an econometric model is developed which is composed of three equations identifying forestry production, conversion from open forest to closed forest and conversion from other land uses to closed forest so as to explore the impacts on the forest area changes from demographic, social, economic, location and geophysical factors. On this basis, we employ the Dynamics of Land System (DLS) model to simulate land-use conversions between forest area and non-forest cover and the land-use conversions within the sub-classes of forest area for the period 2000–2020 under business as usual scenario, environmental protection scenario and economic growth scenario. The simulation results show that forest area will expand continuously and there exist various kinds of changing patterns for the sub-classes of forest area, for example, closed forest will expand continuously and open forest and shrub will decrease a little bit, while area of other forest will keep intact. The research results provide meaningful decision-making information for conserving and exploiting the forest resources and making out the planning for forestry production in the Northeast China region. 相似文献
6.
鄱阳湖湖区核心生态系统服务功能空间辨识 总被引:1,自引:0,他引:1
根据千年生态系统评估提出的评估概念框架,考察鄱阳湖湖区生态系统服务功能的形成机理,构建了鄱阳湖湖区生态系统服务功能表征指标体系,并利用多主题1km栅格成分数据模型,采用主成分分析法提取了鄱阳湖湖区核心生态系统服务功能综合表征指标。在此基础上,通过空间聚类分析,形成了鄱阳湖湖区生态系统服务功能分区,实现了各分区单元上生态系统服务功能的空间辨识。研究结果表明,鄱阳湖湖区核心生态系统服务功能包括了支持功能、供给功能、调节功能和文化功能,它们在空间上的排列组合形成了鄱阳湖湖区的10个生态系统服务功能分区,本文辨识了鄱阳湖湖区精细栅格水平上核心生态系统服务功能之间的差异及其空间分异特征。本研究提出的生态系统服务功能分区及其空间辨识方案,为鄱阳湖湖区生态系统服务功能的开发与保育提供决策参考信息。 相似文献
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生态系统服务功能动态区划方法与应用 总被引:2,自引:0,他引:2
开展区域生态系统服务功能动态区划,对生态系统服务功能的分区管理具有重要的指导价值。本文介绍了生态系统服务功能区划的方法--生态系统服务功能动态区划系统(SIZES)。该方法包括生态系统服务功能多层次表征、位序矩阵生成、核心生态系统服务功能空间辨识和动态区划边界生成四个模块,它们能实现生态系统服务功能动态区划边界的生成。其中,生态系统服务功能多层次表征模块和动态区划边界生成模块是主要模块,而构建生态系统服务功能表征指标体系和生成区划单元是该方法的关键所在。利用SIZES将锡林郭勒盟划分为6个生态系统服务功能区,科学合理地解释了该区生态系统服务功能空间分异规律,为指导该区生态系统服务功能分区管理,提供了具有时空特性的决策参考信息。 相似文献
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环境监测网络信息系统的开发及其应用——以伊犁地区为例 总被引:3,自引:1,他引:2
随着互联网技术的发展 ,基于因特网的环境监测信息系统表现出越来越多的优越性 :首先 ,由于互联网技术的引入 ,用户使用更加便捷 ;其次 ,基于互联网 ,数据的分发与共享变得更加容易 ;最后 ,在信息高速公路的支持下 ,我们可以建立信息服务网络。因此 ,环境监测网络信息系统的设计对于实现数据的采集、共享和分发具有重要的意义。由于存在多种因素影响区域环境 ,因此 ,要实现综合的环境监测并非易事。鉴于此 ,我们设计并开发了环境监测网络信息系统。 相似文献
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榆林地区景观变化探测模型 总被引:3,自引:1,他引:2
Landscape is a dynamic phenomenon that almost continuously changes. The overall change of a landscape is the result of complex and interacting natural and spontaneous processes and planned actions by man. However, numerous activities by a large number of individuals are not concerted and contribute to the autonomous evolution of the landscape in a similar way as natural processes do. There is a well-established need to detect land use and ecological change so that appropriate policies for the ;egional sustainable development can be developed. Landscape change detection is considered to be effectively repeated surveillance and needs especially strict protocols to identify landscape change. This paper developed a series of technical frameworks on landscape detection based on Landsat Thematic Mapper (TM) Data. Through human-machine interactive interpretation, the interpretation precision was 92.00% in 1986 and 89.73% in 2000. Based on the interpretation results of TM images and taking Yulin prefecture as a case study area, the area of main landscape types was summarized respectively in 1986 and 2000. The landscape pattern changes in Yulin could be divided into ten types. 相似文献
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