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1.
The problem of scale in community resource management   总被引:1,自引:0,他引:1  
Scale is a fundamental variable in most community resource management programs. This is true both in terms of scale as a management concept (i.e., local, regional, and national level management) as well as a mapping concept (i.e., units on the map per unit on the ground). Julian Steward, the father of human ecology, recognized as early as 1950 that social scientists have failed to develop methods for incorporating the effect of scale in their work. This article seeks to determine whether methods used in plant and animal ecology for assessing the effects of scale are applicable to community resource management. The article reviews hierarchy theory and multiple scales, two methods (one theoretical and the other practical) for dealing with problems that span many scales. The application of these methods to community resource management programs is examined by way of an example.  相似文献   

2.
This paper examines the modified patterns of utilizing non-timber forest products (NTFP) and associated behavioral changes around tropical forest areas in the context of conservation-related objectives and other commercially driven objectives. Our study introduces a conceptual framework based on the household production theory and tests empirically the hypotheses drawn at Sinharaja World Heritage in Sri Lanka. The results show that conditions introduced by forest conservation programs and the spread of small-scale commercial tea cultivation are transforming the economy around Sinharaja. The process is an economically rational one where resident communities decide upon their actions based on the opportunity cost of time involved with NTFP in the absence of observable prices. Although the process, overall, has led to a decline in the role of NTFP in the household economy, its impact over different NTFP are not uniform, leaving sustained demand for certain NTFP. This situation calls for a multifaceted approach in forest management programs to address the various household needs fulfilled by NTFP-based activities.  相似文献   

3.
本文分析了棉秆、棉籽壳、棉籽饼和棉油皂脚的开发途径和利用技术,并从我国经济现状和技术水平出发,提出了应该重点开发的领域。  相似文献   

4.
本文针对零价纳米铁(nZVI)在修复受污染地下水中存在的易于团聚、迁移性低及易于老化等问题,详细介绍了近年在这些问题研究上的最新进展,包括材料的改性,改性材料对污染物降解的效果及研究中不同因素的影响等。并就nZVI对难降解复杂有机污染物的降解进行了总结,在此基础上展望了nZVI对一类新兴污染物,药品和个人护理用品(PPCPs)的降解。  相似文献   

5.
It is generally acknowledged that global warming is occurring, yet estimates of future climate change vary widely. Given this uncertainty, when asked about climate change, it is likely that people’s judgments may be affected by heuristics and accessible schemas. Three studies evaluated this proposition. Study 1 revealed a significant positive correlation between the outdoor temperature and beliefs in global warming. Study 2 showed that people were more likely to believe in global warming when they had first been primed with heat-related cognitions. Study 3 demonstrated that people were more likely to believe in global warming and more willing to pay to reduce global warming when they had first been exposed to a high vs. a low anchor for future increases in temperature. Together, results reveal that beliefs about global warming (and willingness to take actions to reduce global warming) are influenced by heuristics and accessible schemas. Several practical implications are discussed.  相似文献   

6.
水泥窑协同处置危险废物过程产生一系列的含Cr、Pb、Cl的危险废物。在实验室中,通过掺加不同Cr、Pb和Cl元素含量的典型危险废物,模拟煅烧熟料,研究Cr、Pb和Cl在水泥熟料中的固化率。结果表明:不挥发性重金属Cr在熟料中的固化率在50%以上,并随着生料中Cr掺加量的增加而增加;难挥发性重金属Pb元素在熟料中的固化率范围为19.69%~22.57%,在生料中Pb元素增加后,固化率则呈先增加后下降的趋势;非金属Cl元素在熟料中的固化率范围为3.30%~5.87%。Cl元素在熟料中的固化率在10%以下,并随着Cl元素掺加量的增加,Cl在熟料中的固化率减小。最后,对比《固体废物生产水泥污染控制标准》(征求意见稿)中水泥产品中Cr和Pb元素含量限值(0.1mg/L,0.05 mg/L),实验结果表明Cr和Pb的浸出含量都在限值范围内,满足标准的要求。  相似文献   

7.
建立了超声萃取GC/MS法测定电子电气产品中12种邻苯二甲酸酯类增塑剂的方法。结果表明:该方法简单快速,灵敏度高,相对标准偏差小于10%,加标回收率为86%~109%;样品处理过程中采用化学毒性小的乙酸乙酯作为萃取溶剂,绿色环保。经过对多批次的各种电子电气产品中12种邻苯二甲酸酯分析测定,均得到满意结果。  相似文献   

8.
近年来,铅蓄电池行业铅污染事故频发,对环境和人体健康造成了严重危害。各级政府高度重视,环境保护部于2011年初开展铅蓄电池行业环保专项检查工作。本文从铅蓄电池行业的生产全过程出发,从产业结构、技术装备、末端治理、环境管理等方面提出铅蓄电池行业铅污染防治措施,为铅蓄电池行业重金属污染防治工作提供了参考依据。  相似文献   

9.
本文对青衣江雅安地区流域段,水体中重金属:Pb,Zn,Cu,Hg,Cd,As的污染状况进行了调查。初步得出:Pb,Zn,Cu,Hg对水体,特别是底泥污染比较明显,此与该区域内近年来铅、锌、铜矿开采、洗选、冶炼业的兴起有关,为此提出了相应的防治对策。  相似文献   

10.
地质医疗矿石的开发已逾2000余年,但至今发展明显落后。本文主要介绍了湖北省具医疗功能的20余种矿石,剖析了医疗矿石的开发现状,并指出今后的开发方向。  相似文献   

11.
根据龙泉驿区生态农业旅游开发的有利条件,提出了打造"中国第一生态桃园"的构思--生态旅游开发思路、主题定位、旅游产品设计等.最后,提出该区生态农业旅游的开发对策与措施.  相似文献   

12.
Abstract: Wastewater impact on drinking water sources was assessed using several approaches, including analysis of three pharmaceuticals and personal care products (PPCPs) – primidone, carbamazepine, and caffeine – as indicators, and determination of precursor concentrations for the disinfection byproduct N‐nitrosodimethylamine (NDMA) using formation potential (FP) tests. Samples were collected in 2006 and 2007 in rivers impacted by wastewater treatment plant (WWTP) discharges, at drinking water treatment plant (DWTP) intakes upstream or downstream from these discharges, and from two WWTP effluents in two watersheds. The levels [10th percentile ? maximum (median)] of primidone, carbamazepine, caffeine, and NDMAFP were 2‐95 (7) ng/l, 2‐207 (18) ng/l, 7‐687 (78) ng/l, and 12‐321 (35) ng/l, respectively. The highest concentrations of primidone, carbamazepine, and NDMA precursors were from one of the WWTP effluents, whereas the highest concentration of caffeine was detected in a river heavily impacted by treated wastewater discharges. The lowest concentrations of the three PPCPs were from a DWTP influent upstream of a metropolitan urban area with minimum wastewater impact. Temporal variations in PPCP and NDMAFP concentrations and streamflows in two selected watersheds were also observed. Furthermore, correlation analysis between caffeine or carbamazepine and primidone was evaluated. The results show that measurement of the two pharmaceuticals and NDMAFP tests can be used to evaluate wastewater impact in different watersheds, whereas caffeine results were more variable.  相似文献   

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