北京市通州区水资源综合承载力

目前,通州区已被定为北京市的新的发展中心,但水资源短缺和污染已经严重限制了当地的可持续发展。本文以可持续发展为原则,基于"自然—社会"水循环,提出了通州区水资源综合承载力量化模型。根据通州区的未来发展规划,设计了3种情景来提高该地区的水资源综合承载力。研究表明水资源短缺严重制约了通州区的城市化进程和可持续发展,外调水、本地区节水和控制污染是解决通州区水资源短缺的有效途径。     

Functionally assessing the sustainability of regional ecosystem services: a case study of Hohhot City

"The value of the world's ecosystem services and natural capital" by R.Costanza et al.in 1997 is generally regarded as a monument to the research of valuing ecosystem services.However,the classification of ecosystem services,the method of various services summation,and the purpose for static global value had many criticisms.Based on a summary of these criticisms and suggestions,further study direction—on the sustainability of ecosystem services—is presented.The two basis indicators in ecology—productivity and biodiversity,respectively characterize the ability of producing and self-organizing—not only represent the internal function of ecosystem,but also can be proportioned to its external function of supporting and providing for human life.Theoretically,the two indicators combined could physically assess the sustainability of ecosystem services based on the traditional procedure of Costanza's.The case study of Hohhot City in 1995-2005 shows that the new model reflects the changes of ecosystem services at spatial and temporal scale,and the functionally adjusted assessment shows the sustainability of Hohhot City became gradually stronger during the study decade.But due to the enormous value per unit of water ecosystem,the minimal loss of water area leads to the final result being opposite to the processing analysis,which gives a clue to the further experimental testing research.     

Discussion on sustainable urbanization in Tibet

After 1995,Tibet entered the stage of accelerated urbanization.The large floating population from outside Tibet has become the driving force for urban expansion and the rising of urbanization rate.After analyzing the changes of urban functions and spatial structure of urban system in Tibet,this paper argues that before 1995 the urbanization in Tibet was mainly driven by administrative function,resulting in certain population migration,whereas in the past dec-ade economic function has become the key factor accelerating urban expansion with the market mechanism creating large-scale inflow of population.The floating population-based urbanization and high population growth in the agri-cultural and pastoral areas of Tibet has promoted the regional economic prosperity,but exerted resources and environ-mental pressure and brought some problems for Tibetan culture protection at the same time.The conflicts and contra-dictions between urbanization and the sustainability of natural resources,environment and social development have been intensified.Addressing these problems,this paper proposes some countermeasures for improving the sustainabil-ity of Tibetan urbanization.     

The potential for reference site resampling in estimating sediment redistribution and assessing landscape stability by the caesium-137 method

The objective of this study was to examine a new resampling methodology for estimating reference levels of ¹³⁷Cs in uneroded locations. Accurate and precise measurement of ¹³⁷Cs is required from reference locations to estimate long-term (c. 40 years) sediment redistribution (SRD) and landscape stability. Without reliable long-term, quantitative erosion data it is extremely difficult for land managers to make optimal decisions to ensure landscape sustainability. To determine the influence of ¹³⁷Cs reference site sampling, particularly under-sampling, on SRD and landscape stability, two statistical approaches were applied to a grid-based data set. Caesium-137 inventories in the reference location (n=36) indicated that data were normally distributed, with a mean inventory of 2150±130 Bq m⁻² (±95% confidence band) and a coefficient of variation of 18%. The two approaches used to determine the effect of under sampling included: (1) one-time random subsampling from the total sample collected, subsamples ranged from n=3 to n=30; from these data means and parametric confidence bands were calculated; and (2) random subsamples (n=3 to n=36) were selected from the total ¹³⁷Cs reference sample, and each subsample was in turn resampled 1000 times with replacement to establish a sampling distribution of means. Thus, an empirically derived mean and 95% confidence bands were established. Caesium-137 activities determined from each approach were input into equations to estimate SRD from two cultivated fields. Results indicate that the one-time random sampling approach for subsamples of size ≤12 significantly over- or under-estimated net SRD, particularly from the gently sloping agricultural field. Computer-intensive resampling produced significantly better estimates of net SRD when compared with the random one-sample approach, especially when a subsample of size three was used. Landscape stability, based on partitioning the agricultural fields into areas exhibiting erosion, stability and deposition, was better approximated for both fields by applying resampling. © 1998 John Wiley & Sons, Ltd.     

全球变化和可持续发展科学

文章回顾了全球变化研究的发展史 ,介绍了IGBP ,IHDP ,WCRP ,DIVERSITAS 4个国际全球变化研究组织的研究方向与核心内容以及它们共同提出的碳循环、食物、水资源三大课题。全球环境变化的实质是人与自然界关系的变化。人类活动改变地球系统动力的强度已经超过自然界变动的限度 ,“人类世”的概念与可持续发展科学应运而生。西方学者认为发达地区与发展中地区之间存在着阻碍可持续发展的鸿沟。笔者从可持续发展科学的角度讨论了发达地区与发展中地区的关系 ,并以我国东部与西部为例 ,指出若能通过政府的可持续发展政策 ,推动各职能系统的工作 ,实现信息、技术、经济的不断交互流动 ,就可以找到消除鸿沟的途径。     

西部开发中水资源利用可持续性评价

水资源可持续利用是西部开发的关键。本文就西部开发中水资源利用可持续性评价问题,从西部水资源对于全国的意义、西部水资源及利用现状两个方面论述水资源利用可持续性评价的重要性;提出将水资源评价纳入不同层次环境影响评价的方法;最后提出包括建立有效的水资源财产权结构、进行水资源价值核算、实施水资源利用总量控制和水资源补偿在内的可持续管理对策及有关技术措施。     

基于生计资产量化的农户分化研究——以重庆市沙坪坝区白林村471户农户为例

农户生计资产的配置结构及其空间分布特征决定着农户生计发展的资源优势和空间可能性,依据农户生计资产结构可以准确地识别其分化情景。研究采用"PRA+3S"相结合的方法,以地理坐标为标识码,建立农户属性与地块空间数据相链接的"农户-土地"数据库,对农户生计资产配置结构、农户类型划分、农户空间分布特征进行了研究。结果表明:(1)农户生计资产配置结构差异明显,113户农户自然资产产值高于平均值,趋于发展农业生产;108户农户各项资产处于平均水平,主要向兼业发展;250户农户自然资产小于0.1,趋于发展非农生产;(2)依据农户生计发展趋势将其划分为农业多样化发展型(16%)、农业专业化发展型(8%)、兼业化发展型(23%)、非农多样化发展型(31%)、非农专业化发展型(22%)。     

流域可持续性理想域和现实状态测度

可持续发展是当今世界各国公认的发展准则,但其概念的模糊性与测度方法的单一性阻碍了这一理念的有效应用。在水生态阈值、经济增长底限值和社会发展警戒值等共同约束下,水生态保护目标、经济增长目标与社会发展目标等多目标相互博弈而存在区间范围的基础上,提出了流域可持续性及其理想域的概念以及时间、空间、认知、子系统效益博弈关系、可行区间等决定要素。基于优化方法建立流域可持续性理想域测度模型,并以此为基准,提出了考虑流域系统内外相互作用现实状态的改进离差法测度模型。结果表明:流域可持续性理想域和现实状态测度模型更加符合实际情况,且能够反映流域内外的交互作用对可持续性的影响,为今后流域可持续发展评估提供了一种新思路和方法。     

Quantify the landscape effect and environmental sustainability of rural region planning at town scale near metropolis

The urban fringe, which can be seen as a special form of regional ecosystem with a spatial transition from urban to rural areas, has strong heterogeneity and is a typical ecologically sensitive area. The expansion of cities and the landscape effect of the changes have attracted wide attention. The primary aim of this study is to obtain an understanding of the spatial patterns of landscape conversion and the corresponding environmental sustainability. With the help of GIS and Fragstats software, the changes of landscape patterns before and after town planning were compared in An-Ding town of Beijing, of which the sustainability was also revealed based on the ecological footprint using social and economic statistic data. The results showed that the landscape pattern changed greatly during its conversion from several villages to a small town and the landscape fragmentation increased due to road construction. Meanwhile, human disturbance increased with the constructed land extension. For the gap between the ecological footprint and the biological capacity, An-Ding town ran an ecological deficit at that period, which means it was unsustainable. However, the environmental sustainability decreased after planning due to the degraded green land and forest. The results suggested that ecological management should be strengthened during the town planning period.     

Food becoming compost: encountering and negotiating disgust in household sustainability

ABSTRACT

Human encounters with waste can trigger reflections on taken-for-granted assumptions about consumption. Taking this observation as its starting point, this paper explores whether and how the introduction of the kitchen caddy and food waste composting at the municipal scale generates new environmental subjectivities in Australian homes. Using visceral research methods, the paper shows that, other than participation in municipal composting, close encounters with food becoming compost do not trigger more experimental or sustainable relationships with food. Rather, they trigger new configurations of cleanliness, tidiness and storage as participants seek to stabilise their home against the disruptive sight, smell and touch of food becoming compost. In unsettling the boundaries between humans and nonhumans, and cleanliness and chaos, food becoming compost produces visceral disgust among residents who are primed through modern home cultures to maintain cleanliness, control and the prevention of nonhuman intrusions at home. The success of municipal composting thus hinges on households’ commitment to ‘sustainability work’ in placing, storing, cleaning and sealing food to reconfigure the modern home for waste recovery. Reconceptualising municipal composting as a co-production of sensory engagement and household practices, we centre a visceral politics of household sustainability at the heart of municipal composting and resource management.