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81.
The various indigenous uses and structure of chir pine forests were studied in Uttaranchal state of the Indian Republic. A questionnaire survey was conducted in 50 villages of Uttaranchal to gather information on the indigenous uses of chir pine. For the study of community composition and structure of chir pine forest, at least 15 quadrats of 10 x 10 m were selected randomly across various localities, and the number of individuals, along with other dominant tree and shrub species, were enumerated in each quadrat. About 10 indigenous uses of chir pine were prominent in Uttaranchal. Besides resin, an important non-wood product, different parts of chir pine, such as cones, trunk, stems, wood, leaves and bark, were used by the local people. Chir pine is a subject of the folklore and mythology of indigenous cultures in Uttaranchal. Chir pine forest formed three major communities in Uttaranchal viz., sal-pine (Shorea robusta-Pinus roxburghii), pine pure stands and oak-pine (Quercus leucho-trichophora-Pinus roxburghii). These communities sustained various multiple-use trees and shrubs along with various edible mushrooms (eg. Agaricus campestris, Morchella esculenta and Sparassis crispa). The results of this study are discussed in the light of chir pine conservation and management policies.  相似文献   
82.
The Kuna are a strong and independent culture, however outside influences are imposing growing pressure on their people. Overpopulation and large-scale overfishing are among the most severe threats. The Kuna have developed their own management strategies to address these pressing issues. This study presents local perceptions and attitudes towards marine resource management of six indigenous fishing communities in Kuna Yala, Panama. Results highlight significant general and comparative differences in fishermen's attitudes and perceptions based on socio-cultural structures of communities, occupation and role in local decision-making. The level of cultural survival in communities was a strong indicator for different priorities and attitudes. Differences were also evident based on the level of marine resources used for income generation. Participation in local decision-making processes had positive impacts on levels of knowledge and information, and fostered critical thinking among participants. In addition, the results also denoted that conservation and development were more effective in the long term if the host population could develop strategies and plans for biodiversity conservation. Ownership and empowerment were strong indicators that influenced local livelihood to promote sustainable use of marine resources.  相似文献   
83.
城市绿化的发展思路 --绿色空间建设   总被引:5,自引:0,他引:5  
分析了传统城市绿化过程中存在的对城市绿化理解的不足,提出了城市绿色空间的概念,是对城市绿化概念的拓展。分析了目前我国城市绿化存在的一些问题,并针对这些问题,对传统园林绿化忽略的一些问题进行了论述,指出城乡交错带的绿化、城市自然保留地、特殊空间绿化、绿色廊道建设、郊野公园建设、废弃地的绿化等是城市绿化重要的有机组成部分,在城市绿化建设过程中应该得到重视  相似文献   
84.
苯酚存在对生物强化系统降解2,4-二氯酚的影响   总被引:5,自引:1,他引:4  
研究了采用生物强化技术降解废水中2,4-二氯酚(简称2,4-DCP)时,不同浓度的苯酚存在对生物强化系统降解2,4-DCP的影响,并通过半连续流实验研究了苯酚长期存在下强化系统中2,4-DCP和苯酚生物降解速率的变化趋势.结果表明,苯酚浓度为10mg/L,50mg/L,100 mg/L及300mg/L时,都会对强化系统中2,4-DCP的降解速率产生一定的抑制作用,而且抑制作用随着苯酚浓度的增加而增强.不同浓度的苯酚与2,4-DCP长期共存时,2,4-DCP的降解速率表现出下降的趋势,而苯酚的降解速率则有所增强.  相似文献   
85.
The accumulation of heavy metals (HMs) in soils is potentially hazardous to human, livestock and plant species. HMs in the combined pollution soils and indigenous plants were investigated in a non-ferrous metal-smelting area. The purpose of this study was to determine the HMs in the contaminated soil and different plant species found growing on it, as well as calculation of bioaccumulation coefficients (BACs). Representative sampling sites were identified according to the land-use types. A total of 12 surface soil samples and 32 plant samples were collected. HMs were analysed by inductively coupled plasma mass spectrometry. The levels of soil pollution were assessed using Nemerow’s synthetical contamination index method. The synthetical index was in the range of 16.81–198.11. This result indicated a heavy burden on local environment. HM concentrations in plants were directly related with soil concentrations. The average BACs of five metals were found in the order of Cd (0.309)?>?Zn (0.178)?≈?Pb (0.160)?>?Cu (0.105)?>?Sb (0.0672). Spontaneous weeds including Chenopodium album Linn, Kochia scoparia and trees of Leuce, Ulmus pumila were deemed HM accumulators. The results provided a practical basis for phytoremediation of HM-contaminated soils using accumulator species.  相似文献   
86.
For centuries, local and indigenous water rights and rules in the Andean region have been largely neglected and discriminated against. The process of undermining local communities’ water access and control rights continues up to today and not only is it headed by powerful local, national and international water‐use actors encroaching local rights — it is also a direct consequence of vertical State law and intervention practices, and the latest privatization policies. Recognition of and security for the diverse and dynamic local rights and management frameworks is crucial for improving rural livelihoods and even national food security in Andean countries. At the request of the Government of Ecuador — in which at that time the indigenous movement had its political participation — a research mission was organized to formulate a proposal for institutional reform, aiming at the strengthening of the national irrigation sector. In this article, some basic mission results are outlined and analyzed within the scope of four concepts (institutional viability, political democracy, equity, and water rights security), and practical elements for institutional reform are suggested, not only for the Ecuadorian irrigation sector but also other settings. The complementary roles of central Government, local governments and water user organizations in water resources management are emphasized as is the need to strengthen enabling legal and policy frameworks. The importance of translating constitutional recognition of local and indigenous rights and common property systems into practical procedures and institutional structures is also stressed.  相似文献   
87.
Despite large investments that have gone into meeting the challenges of effective waste management in urban Nigeria, there is little evidence that such efforts are having their expected impacts. Consequently, much attention has been drawn to the need to evolve more sustainable waste management strategies. Drawing on data from in-depth interviews among the Ngwa of southeastern Nigeria, some useful indigenous solid and liquid waste management techniques, in the search for solutions to the current waste management crisis in urban Nigeria, have become evident. These indigenous techniques and practices, which include ingenious and careful waste segregation and sorting, selective burning and burying, composting and conversion, etc., offer scope for meeting the challenges and addressing the limitations of current waste management in urban areas, especially if they are supported by appropriate inputs from modern technology.  相似文献   
88.
黔西土法炼锌区Pb、Zn、Cd地球化学迁移特征   总被引:9,自引:3,他引:6  
黔北土法炼锌致使Pb、Zn、Cd在土壤和水体大量积累,危及到整个生态系统.以小流域为例,探索了废渣、土壤、水体的Pb、Zn、Cd地球化学形态及其迁移性.结果表明,冶炼废渣的Pb、Zn、Cd含量分别为4 632、 8 968、 58 mg·kg-1;污染土壤Pb、Zn、Cd含量分别达到234、 400、 9.6 mg·kg-1.废弃地的地球化学形态分析表明,污染土壤的Pb、Zn、Cd可交换态含量较高,具有较大迁移性和生物有效性,相对而言,废渣中Pb、Zn、Cd具有很低的生物有效性和迁移性,交换态含量低于0.2%.冶炼区的地表水受到严重的Pb、Zn、Cd污染,地下水重金属含量未超出三类水体的质量标准.在地表水体中,可溶态的Pb、Zn、Cd含量少,主要以悬浮态存在,表明了河流重金属污染主要来自于沿岸水土流失.  相似文献   
89.
The Idle No More (INM) movement entered public view in November 2012 as a grassroots response to Canadian federal legislation Bill C-45, an omnibus bill that reduced environmental protection of lands and waters. Backed by new media technologies, Indigenous activists and their Settler Canadian allies took a series of online and offline actions to bring public attention to Bill C-45’s devastating implications and the socio-economic sufferings of Indigenous people across Canada. This explorative study examines how INM was reported by nine Canadian print media during its initial upsurge from December 2012 to January 2013. A mixed-methods content analysis reveals that although there were numerous supportive voices discussing INM’s contributions to Indigenous self-determination and environmental protection, they were overwhelmed by anti-INM rhetoric advanced by Postmedia Network and its affiliated titles. The study thus highlights the importance of promoting communication and media alternatives for future struggles against capitalism’s appropriation of nature.  相似文献   
90.
Izquierdo AE  Grau HR  Aide TM 《Ambio》2011,40(3):298-309
Global trends of increasing rural–urban migration and population urbanization could provide opportunities for nature conservation, particularly in regions where deforestation is driven by subsistence agriculture. We analyzed the role of rural population as a driver of deforestation and its contribution to urban population growth from 1970 to the present in the Atlantic Forest of Argentina, a global conservation priority. We created future land-use-cover scenarios based on human demographic parameters and the relationship between rural population and land-cover change between 1970 and 2006. In 2006, native forest covered 50% of the province, but by 2030 all scenarios predicted a decrease that ranged from 18 to 39% forest cover. Between 1970 and 2001, rural migrants represented 20% of urban population growth and are expected to represent less than 10% by 2030. This modeling approach shows how rural–urban migration and land-use planning can favor nature conservation with little impact on urban areas.  相似文献   
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