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931.
研究江西大余县荡坪国有钨矿尾砂库区自然植物组成分布及其重金属富集特征,旨在为今后矿区植被重建与植物修复重金属污染土壤提供科学依据。结果表明:库区共出现了20种植物,隶属15科20属,其中草本植物14种,木本植物6种;这些植物明显生长不良,且主要分布在库区湿润或有水出现的沙土地区。尾砂库区中,不同重金属含量在同一植物体内大小趋势为Zn>Pb>Cu>Cd。库区没有发现重金属的超富集植物,大部分为Cu、Pb、Zn、Cd的耐性植物。荡坪尾砂库区土壤Cd污染严重,木贼与蜈蚣草为Cd的避性植物,可用于库区Cd污染土壤的植被重建先锋物种;土荆芥与香附子为Cd的积累植物,可以用于库区Cd污染土壤的植物修复;其它植物为Cd的排斥植物,可用于库区Cd污染土壤的植物固化.  相似文献   
932.
Purva Jain 《Local Environment》2016,21(11):1409-1419
Many Indian Protected Areas (PAs) act as a support system for the communities living in and around them. Large-scale human interventions in these PAs have resulted in biodiversity loss, threat to wildlife and habitat fragmentation. The Sariska Tiger Reserve (STR) is no exception. In this reserve, tiger (Panthera tigris) became extinct in 2004.To create inviolate space for the reintroduced tigers, government has planned voluntary relocation of villages located inside Critical Tiger Habitat. The voluntary relocation plan will be more challenging if people are not willing to get relocated from PAs. Therefore, we have empirically analysed the identified factors influencing local communities’ willingness in getting relocated outside the STR using logit model. Results revealed that “restriction of access” and “market access” are the most influential factors and positively associated while forest dependency is negatively associated with local communities’ willingness. Based on these results, it was recommended that policy should be directed towards restriction on accessing forest resources along with reduction in forest dependency by nurturing and strengthening villagers’ livelihood to ensure successful relocation. Displacement of existed small markets around the reserve will also persuade them to relocate in areas more connected to market and other facilities.  相似文献   
933.
Reconciling conservation and social justice imperatives is a major challenge facing many postcolonial states worldwide. Where historically disenfranchised communities have laid legal claim to protected areas, the typical resolution has been collaborative management agreements between the state and claimant communities. The real outcomes of such strategies for people and ecosystems have been seriously questioned, although alternative approaches are seldom explored. Here, we reflect on one such alternative that was pursued in a case in South Africa, where the land was handed back to the community and a replacement protected area created. Our objective was to explore the opportunities and trade-offs associated with this approach for communities and conservation agencies alike, and to compare these to typical collaborative management outcomes. Methods included key informant interviews, focus group discussions and household surveys. We find that, surprisingly, this approach created more benefits for the conservation agency than for claimant communities. Indeed, the community experiences bore a striking resemblance to those experienced in collaborative management settings: intra-community conflict, confusion over leadership and serious questions about the boundaries of the “community”. Processes aimed at redressing past injustice in disputes over conservation land, regardless of the approach adopted, must bring with them a strong commitment to building institutional and leadership capacities within communities, and pay serious attention to the ways in which equity and social justice can be fostered after the settlement of a land claim. Settlement agreements are frequently treated as the final step towards social justice, but are in fact just the beginning.  相似文献   
934.
采用电动力学方法修复重金属污染土壤。研究中采用高岭土模拟铜污染土壤,结合电动力学修复理论,考察了不同电压、添加络合剂条件下铜的修复效果。结果表明,当电压强度为0.5V/cm时,最靠近阴极部分的土壤中Cu^2+的C/C。为1.596,当电压强度为1V/cm时,C/C0为2.245,说明适当提高电压强度能够有效的增加Cu^2+的迁移效果;土壤中未加入络合剂时,Cu^2+大部分集中在第5段土壤中,C/C0为1.339,在土壤中加入络合剂以后Cu^2+大部分集中在靠近阴极部分的土壤中,C/C。为1.716,说明在污染土壤中加入一定量的络合剂可以与Cu^2+结合生成螯合物,提高Cu^2+的迁移效果。  相似文献   
935.
"5.12"汶川地震造成灾区尤其极重灾区严重的生态破坏。论文以都江堰市为例,利用遥感(RS)和地理信息系统(GIS)等手段对震害区土地利用/植被覆盖变化进行监测,对动态变化进行定量分析,得到都江堰市地震生态受损及灾后两年生态恢复信息,并结合DEM对变化信息进行空间分析,研究灾害发生、生态恢复与坡度的相关关系,从而为灾区生态环境的恢复重建和保障生态安全提供借鉴和依据。  相似文献   
936.
以贵州省黔东南州西江苗寨为例,通过田野调查了解西江苗寨的旅游发展历程,在分析旅游开发对西江苗寨民族文化产生积极作用的基础之上,探析旅游快速发展背景下的西江苗寨民族文化旅游开发问题。针对西江苗寨旅游开发过程中出现的问题,提出西江苗寨民族文化保护性旅游开发对策。  相似文献   
937.
Local ecological knowledge (LEK) has been found to be one of the main bridges to manage biocultural diversity. We analyzed the factors affecting LEK maintenance and transmission in a Mediterranean watershed. We used a mixed methods approach to evaluate the agricultural LEK in three different dimensions: biological, soil and water management, and forecasting. We found that the main factors for its maintenance were the respondent''s time living in the area and the social relationships established among farmers, which involved partner collaboration and farmer information exchanges. Protected areas also played a key role for maintaining the LEK associated with soil and water management. Finally, we found that outmigration and mechanization were the most important indirect drivers of change underlying LEK erosion. We suggest that environmental policies should focus on promoting this experiential knowledge, considering both intergenerational renewal and the gendered aspects of this knowledge.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-014-0556-1) contains supplementary material, which is available to authorized users.  相似文献   
938.
以扬州古运河河水和表层沉积物为研究对象,实验室静态模拟实验比较研究了沸石与生物沸石(即附着高效异养硝化菌和好氧反硝化菌的沸石)薄层覆盖削减富营养化景观水体氮效果,考察了生物沸石薄层覆盖削减氮可行性,探讨了生物沸石薄层覆盖削减氮的机理和影响因素。实验结果表明,当实验历时21d时,2kg/m^2(2mm厚)的沸石和生物沸石覆盖对上覆水体TN的削减率分别为36.92%和60.41%,生物沸石比沸石对TN削减率提高了23.48%,高效菌的生物脱氮作用明显;21d后生物沸石覆盖对TN的削减率维持在60%~75%,但生物沸石相对于沸石削减氮的效果有降低趋势。实验后期碳源不足是影响高效菌生物脱氮的主要影响因素。可见,生物沸石薄层覆盖削减富营养化景观水体氮是可行的,但需要进一步研究强化高效反硝化细菌适应能力方法。  相似文献   
939.
饮用水功能区水环境健康风险阈值体系研究   总被引:1,自引:0,他引:1  
结合天津市饮用水功能区水环境现状,筛选出14种特征污染物,通过危害识别将其分为化学致癌物、非致癌有毒物和特殊物质3类。针对不同类别污染物建立健康风险评价模型,给出化学致癌物的致癌强度系数、非致癌有毒物参考剂量、人均寿命、不同年龄段人群日均饮水量和平均体重等参数,建立针对不同人群的饮用水功能区水质风险阈值体系。在此基础上,对天津市饮用水功能区——于桥水库进行水质风险进行评价。结果显示,于桥水库国控监测点位10个监测指标中,氨氮、挥发酚、汞、铅具有健康风险,4个指标的浓度均处于10-7的风险水平以下,说明于桥水库水环境健康程度较好,4个指标对成人及儿童的风险水平排序为铅氨氮汞挥发酚,重金属铅是主要健康风险污染物。  相似文献   
940.
This paper presents a study that aims at evaluating the leaching characteristics of petroleum contaminated soils as well as their application in hot mix asphalt concrete. Soil samples are environmentally characterized in terms of their total heavy metals and hydrocarbon compounds and leachability. The total petroleum hydrocarbon (TPH) present in the PCS before and after treatment was determined to be 6.8% and 5.3% by dry weight, indicating a reduction of 1% in the TPH of PCS due to the current treatment employed. Results of the total heavy metal analysis on soils indicate that the concentrations of heavy metals are lower when extraction of the soil samples is carried out using hexane in comparison to TCE. The results show that the clean soils present in the vicinity of contaminated sites contain heavy metals in the following decreasing order: nickel (Ni), followed by chromium (Cr), zinc (Zn), copper (Cu), lead (Pb), and vanadium (V). The current treatment practice employed for remediation of the contaminated soil reduces the concentrations of nickel and chromium, but increases the concentrations of all remaining heavy metals.  相似文献   
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