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951.
根据环境意识结构.设计了旅游管理部门环境意识调查问卷。其主要的指标体系包括:旅游环境知识水平、旅游环境态度、旅游环境评价和旅游环境行为四个方面。对指标体系各部分之间以及每一指标部分的每一题目之间的相对重要性进行权重的确定.而且对各部分的每道题目的各个选项予以赋分。基于权重和赋分.结合调查问卷的实际情况,设计了指标体系各部分评价模型和环境意识总体评价模型。以此来计算草原旅游发展中旅游管理部门环境意识水平的综合得分。经过分析得知,旅游管理部门环境意识模式是“环境知识制约型”模式。  相似文献   
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954.
A method for simultaneous quantitative determination of alkyl benzyl, dialkyl and trialkyl quaternary ammonium compounds (QACs) has been developed, validated and subsequently applied to real water samples in Austria. The method employs liquid-liquid extraction (LLE) followed by liquid chromatography/tandem mass spectrometry (LC-MS/MS), using electrospray ionization (ESI) in positive mode. The overall method quantification limits range from 4 to 19ng/L for the enrichment of 500mL water samples and analyte recoveries are between 80 and 99%. The method was applied to 62 of the respective water samples without filtration to avoid the loss of the analytes due to the high adsorption capacity of these compounds. Maxima in the mg/L range, especially in the wastewater of hospitals and laundries, could be detected for the selected target compounds.  相似文献   
955.
Occurrence and fate of 45 pesticides and 40 pesticide degradates were investigated in four contrasting agricultural settings--in Maryland, Nebraska, California, and Washington. Primary crops included corn at all sites, soybeans in Maryland, orchards in California and Washington, and vineyards in Washington. Pesticides and pesticide degradates detected in water samples from all four areas were predominantly from two classes of herbicides--triazines and chloroacetanilides; insecticides and fungicides were not present in the shallow ground water. In most samples, pesticide degradates greatly exceeded the concentrations of parent pesticide. In samples from Nebraska, the parent pesticide atrazine [6-chloro-N-ethyl-N'-(1-methylethyl)-1,3,5-triazine-2,4-diamine] was about the same concentration as the degradate, but in samples from Maryland and California atrazine concentrations were substantially smaller than its degradate. Simazine [6-chloro-N,N'-diethyl-1,3,5-triazine-2,4-diamine], the second most detected triazine, was detected in ground water from Maryland, California, and Washington. Metolachlor [2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl)acetamide] rarely was detected without its degradates, and when they were detected in the same sample metolachlor always had smaller concentrations. The Root-Zone Water-Quality Model was used to examine the occurrence and fate of metolachlor at the Maryland site. Simulations accurately predicted which metolachlor degradate would be predominant in the unsaturated zone. In analyses of relations among redox indicators and pesticide variance, apparent age, concentrations of dissolved oxygen, and excess nitrogen gas (from denitrification) were important indicators of the presence and concentration of pesticides in these ground water systems.  相似文献   
956.
The importance of the use of potassium in agriculture is increasing in South Asia for making most productive use of the nutrient in terms of economic returns. Nutrient supply traditionally by cattle manure is constrained by its insufficient availability. Municipal waste compost may be an alternative source of nutrient supplements. Field experiments were conducted at the Experimental Farm of Calcutta University, West Bengal, India during the wet seasons of 1997, 1998 and 1999 on flooded lowland rice. Potassium fractions in municipal waste compost and cattle manure were determined by sequential extraction and also the potassium uptake by rice to compare the effectiveness of municipal waste compost with traditional manure. Potassium was significantly bound to the organic matter in municipal waste compost. Potassium uptake by rice grain and straw increased significantly with the combined application of organics and fertilizers and it was higher in grain than in straw. Water-soluble and non-exchangeable potassium contents of municipal waste compost and cattle manure were highly correlated with the uptake of potassium by straw and grain. Exchangeable and residual potassium were also significantly correlated with the uptake of potassium by straw and grain of rice. Much higher uptake of K in rice straw and rain resulted from applying the manures in conjunction with fertilizers than when applied singly.  相似文献   
957.
Volunteer monitoring of natural resources is promoted for its ability to increase public awareness, to provide valuable knowledge, and to encourage policy change that promotes ecosystem health. We used the case of volunteer macroinvertebrate monitoring (VMM) in streams to investigate whether the quality of data collected is correlated with data use and organizers' perception of whether they have achieved these outcomes. We examined the relation between site and group characteristics, data quality, data use, and perceived outcomes (education, social capital, and policy change). We found that group size and the degree to which citizen groups perform tasks on their own (rather than aided by professionals) positively correlated with the quality of data collected. Group size and number of years monitoring positively influenced whether a group used their data. While one might expect that groups committed to collecting good-quality data would be more likely to use it, there was no relation between data quality and data use, and no relation between data quality and perceived outcomes. More data use was, however, correlated with a group's feeling of connection to a network of engaged citizens and professionals. While VMM may hold promise for bringing citizens and scientists together to work on joint conservation agendas, our data illustrate that data quality does not correlate with a volunteer group's desire to use their data to promote regulatory change. Therefore, we encourage scientists and citizens alike to recognize this potential disconnect and strive to be explicit about the role of data in conservation efforts.  相似文献   
958.
抑制斑点噪声的SAR与多光谱图像融合方法   总被引:1,自引:0,他引:1  
通过将主成分变换与IHS变换相结合,避免了会导致SAR信息量损失的滤波过程,实现了一种可降低SAR斑点噪声影响的遥感影像融合算法。与主成分变换融合方法、IHS变换融合方法在主观视觉效果分析和客观统计参数两方面进行比较,新方法不仅很好地保留了多光谱影像的光谱信息,增强了结果影像的空间细节表现能力,而且有效地抑制了SAR斑点噪声,提高了结果影像的信息量与清晰度。  相似文献   
959.
An assessment of the pollution status of River Illo, located within River Owo catchments area in Ota, Ogun State, Nigeria, was carried out. The River’s response to deoxygenation due to BOD loading from an abattoir and its dissolved oxygen (DO) level was predicted using the modified Streeter-Phelps model. The average concentrations of measured parameters at the sampling stations include: 2.24 mg/l of DO, 312.85 mg/l of BOD, 782.86 mg/l of chemical oxygen demand, and 620.76 g/l of total solids. The DO model for River Illo showed a positive correlation between measured and calculated DO, while the dissolved oxygen curve gave a double spoon shape of two major segments with distinct zones of degradation, decomposition, and recovery. The self-purification factor (f) for both segments ranged between 0.8 and 1.1 depicting River Illo as a slow moving or sluggish river. The above results revealed slow reaeration of the water body while full recovery from pollution was difficult. The treatment of River Illo before usage is very essential to ensure public health safety of users from waterborne diseases.  相似文献   
960.
区域洪水灾害风险评估体系(Ⅰ)——原理与方法   总被引:4,自引:2,他引:2  
区域洪水灾害风险评估是一个新的研究领域。从洪水灾害系统的概念出发,首先阐述了洪水灾害风险管理系统、洪水风险评估及风险类型划分;然后从指标选取原则、指标层次结构、指标量化、风险等级、风险指数等方面构建了洪水灾害风险评估指标体系;接着分析了矢量面状及栅格点状的洪水灾害风险评估单元;最后,介绍了适合区域洪水灾害风险评估的层次分析法、模糊综合评价法及空间分析方法。  相似文献   
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