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331.
Local residents’ active participation is essential in protected areas to ensure achievement of conservation goals. One of the important steps for ensuring the active participation of local residents is to determine the perceptions and the factors that influence the perceptions of the local residents toward the protected area. In this context, the researchers of this study try to come up with the perception formed among the local residents toward the protected areas and especially toward Kure Mountains National Park (KMNP), the factors that would influence their perceptions and the ways how their perceptions are influenced. Multivariate linear regression was used to examine the putative influence of variables on perceptions toward protected areas. According to study results, the survey respondents have displayed a positive perception toward the protected areas in the world and in KMNP. It was determined that the respondents formed a positive perception from their economic, environmental and recreational interaction with KMNP. Also, the outcomes of this study showed that the perception developed by local residents toward the protected areas in the world and KMNP are influenced by gender, the level of satisfaction derived from the national park, duration of their residence in the national park, and that the perception that KMNP conservation are beneficial for the source values of the area, the current protection works in the world, as well as its impacts on their living conditions. 相似文献
332.
333.
Adapting the RUSLE and GIS to model soil erosion risk in a mountains karst watershed, Guizhou Province, China 总被引:7,自引:0,他引:7
Yue-Qing X Xiao-Mei S Xiang-Bin K Jian P Yun-Long C 《Environmental monitoring and assessment》2008,141(1-3):275-286
Soil erosion is a serious environmental problem in Guizhou Province, which is located in the centre of the karst areas of
southwestern China. Unfortunately, Guizhou Province suffers from a lack of financial resources to research, monitor and model
soil erosion at large watershed. In order to assess the soil erosion risk, soil erosion modeling at the watershed scale are
urgently needed to be undertaken. This study integrated the Revised Universal Soil Loss Equation (RUSLE) with a Geographic
Information System (GIS) to estimate soil loss and identify the risk erosion areas in the Maotiao River watershed, which is
a typical rural watershed in Guizhou Province. All factors used in the RUSLE were calculated for the watershed using local
data. It was classified into five categories ranging from minimal risk to extreme erosion risk depending on the calculated
soil erosion amount. The soil erosion map was linked to land use, elevation and slope maps to explore the relationship between
soil erosion and environmental factors and identify the areas of soil erosion risk. The results can be used to advice the
local government in prioritizing the areas of immediate erosion mitigation. The integrated approach allows for relatively
easy, fast, and cost-effective estimation of spatially distributed soil erosion. It thus indicates that RUSLE-GIS model is
a useful and efficient tool for evaluating and mapping soil erosion risk at a large watershed scale in Guizhou Province. 相似文献
334.
运用InVEST模型,研究秦岭生境质量时空变化及驱动机制,以期为秦岭生态文明建设与秦岭区域可持续发展提供理论依据。结果表明:秦岭土地利用方式以林地和草地为主,主要分布于中、西部,耕地与建设用地主要分布在东、南部。人类对秦岭干扰程度在2000年后开始增加,土地利用变幅超过总面积的2%。1980年、1990年、2000年、2010年、2020年,秦岭的平均生境质量(范围0—?1)分别为0.7592、0.7594、0.7586、0.7585、0.7617,均处于“较高”等级。空间分布上,秦岭生境质量中、西部等级高,而东、南部等级低。在像元尺度上,秦岭生境质量较为稳定,显著变化的区域面积仅为2.74%。显著升高的区域主要集中在西南部略阳、勉县等区县,显著降低的区域主要集中在东部的洛南、商州等区县。秦岭的生境质量表现出显著的空间集聚特征,21世纪后,秦岭高质量生境集聚区域面积扩张,低质量的生境集聚区域面积降低。土地利用程度是影响秦岭生境质量最大的驱动因子,与之呈现显著的负相关关系,且影响范围分布于全域。秦岭生境质量的降低源于人类活动引起生境威胁源——建设用地与耕地的扩张,而生境质量的升高可能源于... 相似文献
335.
用循环经济理念构建沈阳西部生态工业走廊 总被引:2,自引:1,他引:1
从沈阳市建设西部工业走廊的实际出发,提出运用循环经济理念,切实实现沈阳市西部工业走廊中化工、冶金、建材三个园区内各个企业内部、各园区内部企业之间、三个园区之间的物质集成、水和能量的梯级使用与信息集成,以及资源减量化、废物资源化的目标,为沈阳市西部工业走廊建设提供了有益的建议。 相似文献
336.
Farmers’ Perceptions of Climate Change and Agricultural Adaptation Strategies in Rural Sahel 总被引:17,自引:3,他引:14
Farmers in the Sahel have always been facing climatic variability at intra- and inter-annual and decadal time scales. While
coping and adaptation strategies have traditionally included crop diversification, mobility, livelihood diversification, and
migration, singling out climate as a direct driver of changes is not so simple. Using focus group interviews and a household
survey, this study analyzes the perceptions of climate change and the strategies for coping and adaptation by sedentary farmers
in the savanna zone of central Senegal. Households are aware of climate variability and identify wind and occasional excess
rainfall as the most destructive climate factors. Households attribute poor livestock health, reduced crop yields and a range
of other problems to climate factors, especially wind. However, when questions on land use and livelihood change are not asked
directly in a climate context, households and groups assign economic, political, and social rather than climate factors as
the main reasons for change. It is concluded that the communities studied have a high awareness of climate issues, but climatic
narratives are likely to influence responses when questions mention climate. Change in land use and livelihood strategies
is driven by adaptation to a range of factors of which climate appears not to be the most important. Implications for policy-making
on agricultural and economic development will be to focus on providing flexible options rather than specific solutions to
uncertain climate. 相似文献
337.
B. Sen Gupta S. Chatterjee H. Kauffman W. DeGroot 《Environmental pollution (Barking, Essex : 1987)》2009,157(12):3351-3353
This report describes a simple chemical free method that was successfully used by a team of European and Indian scientists (www.qub.ac.uk/tipot) to remove arsenic (As) from groundwater in a village in West Bengal, India. Six such plants are now in operation and are being used to supply water to the local population (www.insituarsenic.org). The study was conducted in Kasimpore, a village in North 24 Parganas District, approximately 25 km from Kolkata. In all cases, total As in treated water was less than the WHO guideline value of 10 μg L−1. The plant produces no sludge and the operation cost is 1.0 US$ per day for producing 2000 L of potable water. 相似文献
338.
松果采摘对小兴安岭主要林型红松土壤种子库和幼苗库的影响 总被引:3,自引:0,他引:3
为了探讨人为采摘松果对小兴安岭主要林型红松(Pinus koraiensis)土壤种子库和幼苗库的影响,选择阔叶红松林以及与阔叶红松林相邻的红松人工林、落叶松(Larix gmelini)人工林、白桦(Betula platyphylla)林和云冷杉林,各设置10 m×240 m的样带,调查了红松土壤种子库和幼苗库。主要结果如下:①主要林型间红松土壤种子库数量具有明显的差异,阔叶红松林最多,落叶松人工林次之,白桦林最少;②鼠类取食过或被破坏等动物侵害的种子占81.9%~90.4%,完好种子只有在阔叶红松林和落叶松人工林中发现,分别为4.3%和4.9%;③红松种子主要分布在0~10 cm层中(71.4%~91.3%);④红松幼苗库的密度云冷杉林最高(1 613株.hm-2),红松人工林最低(167株.hm-2),其中阔叶红松林(296株.hm-2)和白桦林(854株.hm-2)的幼苗密度分别为采摘前的1/68~1/9和1/9~1/4.5;⑤从龄级分布上看,松果采摘前阔叶红松林低龄级幼苗的数量较多,随着龄级的增大明显减少,呈倒J型分布;白桦林各龄级幼苗密度相差不大。人为采摘松果后,阔叶红松林各龄级间密度相差不大;白桦林呈倒J型分布。 相似文献
339.
长白山毛赤杨和白桦/沼泽交错带植物多样性分布格局 总被引:9,自引:0,他引:9
采用样带网格调查方法和香农-威纳多样性指数分析方法,研究长白山毛赤杨、白桦/沼泽交错带和干扰白桦/沼泽交错带植物多样性水平分布和垂直分布格局。结果表明:①毛赤杨、白桦/沼泽交错群落植物多样性随着交错区环境梯度变化呈现出凸型水平分布格局,其植物多样性指数为相应地段森林群落的1.5倍,沼泽群落的2~3倍。干扰白桦/沼泽交错群落植物多样性随着交错区环境梯度变化呈现出凹型水平分布格局,其植物多样性指数仅相当于相应地段沼泽群落或森林群落的80%左右,仅为毛赤杨、白桦/沼泽交错群落的70%;②毛赤杨、白桦/沼泽交错群落植物多样性呈现“金字塔型”垂直分布格局,其垂直分布格局是草本层(5):灌木层(3):乔木层(1)。而干扰白桦/沼泽交错群落植物多样性垂直分布格局为草本层(5):灌木层(0.4):乔木层(1),并未呈现典型“金字塔型”分布。因此,人为经营活动不仅降低了森林/沼泽交错带植物多样性水平,也改变了其分布格局。 相似文献
340.
西昆仑北带库地一带广泛发育基性岩墙群(辉绿岩),其化学成分为拉斑质玄武岩系列。岩脉的微量元素与稀土元素具典型的板内溢流玄武岩特征,富集大离子亲石元素、轻稀土,稀土元素总量较高,弱的Eu正异常。Ta、Nb、Hf、Zr无亏损现象,反映岩脉未受到地壳物质的明显混染及经历了弱的结晶分异作用;而Sr、P明显亏损。则反映了亏损的源区性质,但不相容元素的比值表现出EMI特征,推测不相容元素富集是软流圈地幔上涌过程中低程度熔融所致。综合本文的研究及野外地质特征。表明辉绿岩是古塔里木南缘新元古代大陆裂解背景下的产物。 相似文献