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571.
借鉴会计学复式记账核算的优点,在国际资源核算体系的基础上,根据我国自然资源资产核算需求,提出土地资源资产核算的复式记账体系和报表编制框架。研究认为,基于复式记账的土地资源资产核算和报表编制要以“摸清家底、反映自然资源负债、提供土地资源审计和绩效考核信息”为目标,明确区、县级自然资源局为土地资源资产受托管理和进行土地资源资产核算与报表编制的核算单位。在界定土地资源资产、负债和权益相关概念的基础上,提出土地资源资产属性变化的核算内容和每次土地资源资产实物量变化必须遵循占补平衡的基本原则,进行过程核算。以YC县土地资源资产变化为例,对土地资源资产变化进行了基于复式记账的土地资源资产核算与报表编制实证研究,确定核算的事项类型和特征及其借贷核算流程,编制出土地资源资产负债表,并同时进行实物量核算和价值量核算的报表编制,结果表明:YC县土地资源资产实物量1485 km^2,2018年末价值量5639874.22万元、经济权益5271874.22万元、生态权益367991.6万元,土地资源负债8.40万元,通过土地资源资产用途调整,土地资源资产价值量增加21319.42万元,但在调整过程中,形成了土地资源负债0.07 km^2(8.4万元),在以后土地整治中需要增加园地。 相似文献
572.
Seventy-two squares of 100 ha were selected by stratified random sampling with probabilities proportional to size (pps) to survey landscape changes in the period 1996–2003. The area of the plots times the urbanization pressure was used as a size measure. The central question of this study is whether the sampling with probabilities proportional to size leads to gain in precision compared to equal probability sampling. On average 1.03 isolated buildings per 100 ha have been built, while 0.90 buildings per 100 ha have been removed, leading to a net change of 0.13 building per 100 ha. The area with unspoiled natural relief has been reduced by 2.3 ha per 100 ha, and the length of linear relicts by 137 m per 100 ha. On average 74 m of linear green elements have been planted per 100 ha, while 106 m have been removed, leading to a net change of −31 m per 100 ha. For the state variables ‘unspoiled natural relief', ‘ linear relicts', ‘removed linear green elements', and ‘new – removed linear green elements' there is a gain in precision due to the pps-sampling. For the remaining state variables there is no gain or even a loss of precision (`new buildings', ‘removed buildings', ‘new – removed buildings', ‘new linear green elements'). Therefore, if many state variables must be monitored or when interest is not only in the change but also in the current totals, we recommend to keep things simple, and to select plots with equal probability. 相似文献
573.
The Atlantic Coastal Action Program (ACAP) is a unique, community-based program initiated by Environment Canada in 1991 to help Atlantic Canadians restore and sustain watersheds and adjacent coastal areas. ACAP is the eastem-most Environment Canada Ecosystem Initiative. The ACAP family is currently made up of 14 ecosystem-based organizations in the four Atlantic provinces. Each one of these non-profit organizations operates independently, but is formally linked under the umbrella of ACAP to represent a force stronger than the individual parts. In Environment Canada's experience, the program consistently demonstrates the value of a community-based approach and produces results on an ecosystem basis. This paper will examine some of the impacts of ACAP in terms of economics, credible community science, and environmental results which most often align with Environment Canada's objectives. It will explore the influences of the community-based approach to environmental management on multiple scales (local, regional, etc.). Through examples, the paper will demonstrate the effectiveness of ACAP in influencing some of the policies, programs and attitudes of various levels of government and industry in the region, as well as describe how the community-based model has been exported internationally. The paper will conclude with a discussion on a planned path forward for ACAP. 相似文献
574.
Sargaonkar A 《Environmental monitoring and assessment》2006,117(1-3):491-503
Non-point source (NPS) pollution is the result of various land use practices such as agriculture, sites of construction and
waste disposal, urban development and so on. The control of NPS pollution is possible by regular monitoring and assessment
on watershed basis to educate people for implementing well-known structural and non-structural measures. Recent trend is to
use GIS based modelling tool for assessment of rainfall-runoff and non-point loading. The approach requires generation and
analysis of basin wide data on various features of land and estimates of Event Mean Concentrations (EMCs) of pollutants in
the runoff. In the present paper, basin wide data in different districts of Tapi basin has been analysed for land use distribution;
fertilizer application; low, medium and high-density habitation; and annual rainfall. Coefficients of runoff have been estimated
considering pervious and impervious area for different land use types, and compared with the reported values for Indian conditions.
The estimated mean annual runoff flow indicated that two districts Jalgaon and Dhule contribute maximum runoff to the Tapi
River. Estimates of EMCs for BOD and nutrients (N and P) in the runoff from various districts are useful in GIS-based modelling
study for NPS pollution assessment. 相似文献
575.
576.
577.
土地利用/覆盖变化对长江上游非点源污染影响研究 总被引:27,自引:6,他引:21
在国内外相关研究的基础上,利用输出系数模型,结合RS和GIS技术,对长江上游的非点源污染负荷进行了空间模拟和负荷估算.模拟结果表明,在不考虑流域损失的前提下,由于土地利用造成的非点源污染负荷TN总量从20世纪70年代的123万t下降至2000年的116万t,基本呈逐年减少的趋势,由土地利用造成的TP的变化趋势与TN基本相同,从70年代的3.7万t下降到2000年的3.5万t左右.就省份、土地利用类型和水系而言,四川省、种植用地和草地以及金沙江水系和嘉陵江水系对长江上游的非点源污染贡献较大.在非点源污染负荷强度上,重庆市和嘉陵江水系单位面积负荷最高,是今后应重点治理的地区.结果表明,该模型可以对长江上游这样的超大尺度空间的非点源污染进行较好的空间模拟. 相似文献
578.
Tam CL 《Environmental management》2006,38(1):1-15
Participatory environmental and resource management is premised on open communication to reach consensus. However, deliberate and open communication cannot adequately address silent conflict. This begs two questions. First, how is the existence of covert communication and silent conflict to be recognized and addressed? Second, how are the wider social relations and traditions that encompass communication and conflict to be described and explained? These questions revolve around communicative power. Communication of environmental knowledge is deeply embedded in social power structures, with direct implications for participatory resource planning and implementation. Ethnographic research conducted at a failed community-managed fish farming project in Southeast Sulawesi, Indonesia shows that a culture of harmony and respect for authority can silence environmental conflict in the hierarchical “community.” Three propositions are offered. First, communication amnesia and exclusion jeopardize participation. Second, cultures of harmony and silent conflict shape planning processes and outcomes. Third, the weak use manipulation and communication strategy to acquire a “voice” while preserving harmony. These propositions address five unresolved issues in participatory resource management: analysis of groups, contextuality, social relationships, nonparticipants, and informal communication. Power, tradition, and social networks affect the valuing of knowledge relative to the power of different individuals and institutions to communicate priorities, values, and needs. These factors are critical to the inclusion of both participants and nonparticipants. 相似文献
579.
Yasamis FD 《Environmental management》2006,38(5):823-836
Improving the performance of the state environmental agencies (SEAs) necessitates an effective institutionalization of governmental
environmental management functions. There are examples of successful and unsuccessful SEAs in several parts of the world.
Analysis and assessment of these cases can deliver useful insights for institution builders. The objective of this article
is the assessment of the institutional effectiveness of the SEAs in Turkey through the perceptions of the experts using the
Delphi Technique. In this regard, a checklist is developed including 16 criteria and 123 subcriteria to measure the institutional
effectiveness of the SEAs. Twenty-eight national and international experts have formed a Delphi panel and evaluated the national
and local conditions. Results, based on the perceptions of the experts, indicate that the overall effectiveness of the SEAs
is far less than satisfactory. Negative consensus has been reached over the effectiveness of 13 of the16 criteria and 95 of
the123 subcriteria; however, no consensus has been achieved over the remainder of the parameters. The survey has also proven
that the Delphi Technique can be effectively used for that purpose. Utilization of the checklist method is also useful in
diagnosing the problematic components of the SEAs. It is recommended that this approach be used in similar cases elsewhere. 相似文献
580.
Bryan BA 《Environmental management》2006,37(1):126-140
The desire to capture natural regions in the landscape has been a goal of geographic and environmental classification and ecological land classification (ELC)
for decades. Since the increased adoption of data-centric, multivariate, computational methods, the search for natural regions
has become the search for the best classification that optimally trades off classification complexity for class homogeneity.
In this study, three techniques are investigated for their ability to find the best classification of the physical environments
of the Mt. Lofty Ranges in South Australia: AutoClass-C (a Bayesian classifier), a Kohonen Self-Organising Map neural network,
and a k-means classifier with homogeneity analysis. AutoClass-C is specifically designed to find the classification that optimally
trades off classification complexity for class homogeneity. However, AutoClass analysis was not found to be assumption-free
because it was very sensitive to the user-specified level of relative error of input data. The AutoClass results suggest that
there may be no way of finding the best classification without making critical assumptions as to the level of class heterogeneity
acceptable in the classification when using continuous environmental data. Therefore, rather than relying on adjusting abstract
parameters to arrive at a classification of suitable complexity, it is better to quantify and visualize the data structure
and the relationship between classification complexity and class homogeneity. Individually and when integrated, the Self-Organizing
Map and k-means classification with homogeneity analysis techniques also used in this study facilitate this and provide information
upon which the decision of the scale of classification can be made. It is argued that instead of searching for the elusive
classification of natural regions in the landscape, it is much better to understand and visualize the environmental structure
of the landscape and to use this knowledge to select the best ELC at the required scale of analysis. 相似文献