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1.
农业升温、再上新台阶的有效选择是农业资源的综合开发。鉴于目前我国农业资源利用中存在的强烈反差这一“基本国情”,在农业综合开发中必须充分认识强烈反差对农业发展的制约和价值,正确处理好内涵开发与外延开发、分散开发与规模开发、示范开发与区域开发之间的关系,并实现由粗放开发向集约开发、单一开发向多元开发、单向开发向双向开发的转变。  相似文献   

2.
我国水电开发研究进展及展望   总被引:1,自引:0,他引:1  
在全球能源供应短缺与国内能源危机的背景下,水电开发研究显得尤为重要.我国水电开发研究内容主要包括:水电开发与能源危机、水电开发与经济发展、水电开发决策、水电开发模式设计、水电开发工程管理、水电开发相关问题及其处理.然而,这些研究忽视了跨国界流域水电开发研究、水电开发跟踪调研、水电开发的定量系统模型构建,今后的研究重点应该是在以上三个方面.  相似文献   

3.
对荒漠旅游资源的特殊性进行分析,总结了荒漠景观观光、荒漠文化遗产考古开发、荒漠探险开发、小众荒漠生态旅游开发、荒漠度假体验开发、沙漠体育公园开发、荒漠主题城市开发等7种模式,有益于荒漠旅游的开发管理实践.  相似文献   

4.
黄土高原地区生态旅游开发的优势及前景分析   总被引:1,自引:0,他引:1  
黄土高原地区生态环境非常脆弱,该区进行旅游开发必须以生态旅游为指导。该区自然和人文旅游资源丰富而独特,开发生态旅游具有类型多样、功能齐全、有利于组合开发的资源优势;西部大开发、中部崛起战略为其提供了政策优势,同时该区劳动力资源丰富,因此开发生态旅游优势明显。分析了黄土高原地区生态旅游开发的国际、国内及区域市场前景,提出了在该区进行生态旅游开发应注意的问题。  相似文献   

5.
通过四明山红色旅游目的地开发建设的优势、机遇及劣势与挑战的分析,提出了开发与建设四明山红色旅游目的地的六大策略,即政府主导与市场运作相结合的开发策略、社会效益和经济效益兼顾的开发策略、红色旅游目的地品牌策略、"红绿结合"的开发策略、区域合作策略、基于和谐旅游发展的开发策略。  相似文献   

6.
《新疆环境保护》2012,34(2):8-8
当前和今后一个时期,各地各部门要重点抓好以下几方面的工作。1.坚持规划先行,以规划引领开发。要借鉴汲取已有的经验教训,规划一开始就要按照"两个可持续"要求搞好顶层设计,高起点、高水平、高效益地编制好规划。确定生态建设和环境保护的底线,科学划定"优先开发区域、重点开发区域、限制开发区域和禁止开发区域"四类主体功能区,明确开发方向,控制开发强度,规范开发秩序。依据主体  相似文献   

7.
当前中国社会的巨大转型和现代社会多元文化的交融,使人文旅游资源的价值倍增。湖南民族地区蕴含着极其丰富的人文旅游资源,但在开发过程中出现了一些失误,因此必须从开发理念、开发重点、开发特色、开发模式等方面入手,全面、有序地推进湖南民族地区人文旅游资源的开发工作。  相似文献   

8.
文章分析了油气能源现状、油气开发与环境的关系、油气开发与环境安全的关系,油气开发中的环境保护对策与环境监理。得出:油气开发既要做到和谐生产,又要保护环境;在油气开发中,对环境有影响的应加大修复力度,采取相应的环境保护措施,确保有效、长效的环境保护目标。  相似文献   

9.
《四川环境》2008,27(4):F0004-F0004
得荣滇能水电开发有限公司是云南滇能迪庆香格里拉水电开发有限公司全资子公司,公司股东为云南滇能投资控股(集团)有限公司、新华联集团有限公司、迪庆投资开发集团有限公司,主要任务是开发得荣县丰富的水能资源,以“开发绿色电力、服务当地经济”  相似文献   

10.
市场需求与重庆都市游特色纪念品的开发   总被引:1,自引:0,他引:1  
作者从增强特色旅游纪念品开发的可操作性出发 ,将开发看成是以链接市场需求为中心的营销策划过程 ,对重庆都市旅游特色纪念品的开发主题、要素整合与展示、相应支持性措施等提出了较具针对性的建议。在充分了解市场需求的基础上 ,将特色纪念品开发与旅游地主题形象及其要素、旅游精品开发密切结合 ,是本文主要突破点。  相似文献   

11.
An attempt was made to investigate the relationship between raw coal characteristics and effluent quality in two coking coal washeries of Central Coalfields Limited, Kedla and Rajrappa in Jharkhand State, India. Coal samples-raw coal feed, washed fine clean coal, washed coarse clean coal, middlings and rejects were collected. Similarly, raw water (intake to washery) and effluent samples generated in the washeries, namely, fine coal jig under water, coarse coal jig under water and slurry pond water were also collected over a period of 6 months. Parameters outlined in Ministry of Environment and Forest (MoEF) Schedule VI Indian standards were determined, both in coal samples and water/washery effluent samples. Apart from the parameters listed in the standard, sodium, potassium, calcium, magnesium, sulphate and chloride found to be present in coal were also determined in coal and water samples. The processing results essentially in production of huge quantities of suspended material, which is beyond the stipulated limit of 100mg/l as specified in the Standard. Lowering of pH was observed in both the washeries. The trace/heavy elements were found to be concentrated in the heavier fractions in rejects produced from the washery. The concentrations of major elements in coal-Na, K, Ca, Mg, and minor elements in coal-Mn; F, SO4 and Cl were found to be higher in process water than in raw water indicating that these elements are transferred from coal to the water in washeries. However, only in the case of Mn, the stipulated limit of the effluent standard was exceeded. Trace elements like As, Se, Hg, Cd, though found to be present in coal, were absent in the process water indicating that these elements are not released by coal during washing.  相似文献   

12.
13.
This study evaluated the US Clean Water Act (CWA) Section 303(d) listing and delisting processes, based on historical and current federal and state guidelines, to determine whether there are regional differences in water quality assessment criteria used by various states to determine impairment of a waterbody for inclusion in the 303(d) list. A review of almost 50 total maximum daily load (TMDL) and delisting documents revealed that the basis for listing or delisting a waterbody varies considerably and that, in many cases, determination of impairment was based on insufficient water quality information. Historical USEPA guidance on the 303(d) listing and delisting processes has been generally broad, resulting in wide interpretation of the assessment criteria by various states. This has led to unclear or conflicting listing methodologies among states, leading to inconsistencies in impairment determination. Common problems include inconsistent data quality and quantity, differences in frequency of monitoring, variable interpretation of narrative water quality standards, and differences in specificity of implementation and monitoring plans, resulting in significant difference in the basis for listing and delisting waterbodies. In response, several states have taken the initiative to provide much more specific guidance for their internal agencies. Listing and delisting criteria are generally clearer at the state level, but the development of differing state guidance documents has resulted in diversity in the development of the 303(d) lists and in the process of delisting a waterbody. While state guidelines are better able to address local considerations, such as variations in climate, landuse, and water quality objectives, as well as social and economic preferences, the variation in listing criteria has led to inconsistencies across state boundaries in the levels of attainment of national water quality objectives. For stakeholders that participate in the 303(d) listing process within a particular state, these types of discrepancies may not have a significant impact. However, these inconsistencies can lead to confusion for some stakeholders who participate in the process in multiples states, and must deal with differing and sometimes conflicting requirements depending on the location of their facilities.  相似文献   

14.
/ An index of upland wildlife habitat was developed to investigate patterns and changes in habitat over time, using four years (1920, 1940, 1964, 1987) and the state of Illinois as an example. The index was composed of two subdivisions that described, at the county level, the quantity of wildlife habitat and a third subdivision that described farming disturbances that impacted the quality of the habitat. Data came from the US Census of Agriculture. The first subdivision that reflected quantity of habitat was called the wildlife habitat subdivision and was the sum of percentage woodland on farms, percentage farmland in nonrow crops, and percentage farmland in set-aside programs. The second subdivision that reflected the quantity of habitat was termed the soil-related features subdivision and was the sum of the percentage of farmland that was not highly erodible, the percentage of farmland in soil-protecting crops, and the percentage of farmland in conservation tillage. The third subdivision, reflecting the quality of the habitat, was the farming disturbance subdivision and was the sum of the percentage of grazing and the percentage of land on which fertilizers, pesticides, and herbicides were applied. Overall, major decreases occurred between 1920 and 1987 in the subdivisions reflecting the quantity of wildlife habitat and a major increase occurred in the subdivision associated with farming disturbance, reflecting the intensification of agriculture in the state. However, there was variability throughout the state, with some counties being more favorable to wildlife (as measured by the subdivisions) than others. Most of the changes within the state for the subdivisions reflecting quantity of upland wildlife habitat occurred during 1940 while changes in the farming disturbance subdivision (reflecting habitat quality) occurred in 1964. By 1987, the western and southern parts of Illinois were the most favorable for wildlife as reflected in all three subdivisions. Upland wildlife harvest indices were related to the subdivisions in 1964 and 1987, when harvest indices were available. Cottontail and northern bobwhite harvests were higher in counties with higher amounts of the wildlife habitat subdivision in both years. Cottontail harvest was also higher in counties with lower levels of the farming disturbance subdivision in 1964 and higher levels of soil-related features subdivision in 1987. Indices at the county level have the potential to be used in a multiscale analysis to investigate the impact of policy changes on large-scale areas of the Midwest and to develop regional perspectives of the impacts of agriculture on upland wildlife and their habitats.KEY WORDS: Upland wildlife; Habitat; Agriculture; Illinois  相似文献   

15.
微塑料作为环境介质中的新型污染物,其对生态系统的影响越来越受到关注。土壤是环境中微塑料的重要蓄积库,结合近些年来国内外关于土壤中微塑料的研究,针对土壤中微塑料的来源、生态效应、分析方法及污染防治进行综述,以便更全面的了解土壤中微塑料污染的现状及其潜在的生态环境风险。塑料包装废弃物、农用地膜破碎、大气沉降是土壤中微塑料的主要来源。微塑料可吸附土壤中的重金属和有机物,作为其他污染物的载体危害生态环境健康,并会随着食物链逐渐富集,从而影响人类健康。土壤中的微塑料可通过筛分干燥后采用密度分离法、加压流体萃取法、石油提取法等进行分离,并通过消解去除土壤中的有机质。土壤中微塑料的识别与表征可采用目检法、红外光谱法、拉曼光谱法、扫描电镜法等。此外,根据土壤微塑料的生态效应提出污染治理措施与未来研究方向展望。  相似文献   

16.
ABSTRACT: Cyto-embryological analyses of fish eggs collected in nature can be a more sensitive indicator of environmental pollution than more typical assays conducted on artificially-spawned eggs. This is because uncertainties associated with artificial spawning and rearing are dispensed with, as well as because of the sensitivity of some cellular and subcellular analyses. At the same time, such measures can provide information on interannual differences in egg viability of importance in elucidating great, unexplained variability in fisheries recruitment. Extensive experience with fish embryos from ocean plankton has led to the choice of a particularly useful, practical suite of observations for different developmental stages. This includes measures of embryo mortality, mutagenicity, teratogenicity, abnormal cell differentiation, and development rate. Atlantic mackerel egg mortality has been determined to be greater in the surface waters of the New York Bight apex and along the New Jersey coast than in less polluted portions of the Bight. Chromosome abnormality of mid-stage embryos was also greater in more impacted areas of the same water mass, as well as in the somatic cells of adult mackerel and winter flounder, and in juvenile and adult windowpane flounder caught in more impacted areas. Mortality and abnormality of the mackerel embryos showed statistical associations with toxic hydrocarbons as measured in plankton, and with heavy metals as measured in sea surface waters. The sensitivity, practicality, and relevance of the cytoembryological studies to population dynamics of resource species make this an important means of monitoring environmental quality.  相似文献   

17.
The interactions between humans, animals and the environment have shaped human values and ethics, not only the genes that we are made of. The animal rights movement challenges human beings to reconsider interactions between humans and other animals, and maybe connected to the environmental movement that begs us to recognize the fact that there are symbiotic relationships between humans and all other organisms. The first part of this paper looks at types of bioethics, the implications of autonomy and the value of being alive. Then the level of consciousness of these relationships are explored in survey results from Asia and the Pacific, especially in the 1993 International Bioethics Survey conducted in Australia, Hong Kong, India, Israel, Japan, New Zealand, The Philippines, Russia, Singapore and Thailand. Very few mentioned animal consciousness in the survey, but there were more biocentric comments in Australia and Japan; and more comments with the idea of harmony including humans in Thailand. Comparisons between questions and surveys will also be made, in an attempt to describe what people imagine animal consciousness to be, and whether this relates to human ethics of the relationships. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

18.
ABSTRACT: Nitrogen inputs to, and outputs from, a 55-acre site in Lancaster County, Pennsylvania, were estimated to determine the pathways and relative magnitude of loads of nitrogen entering and leaving the site, and to compare the loads of nitrogen before and after the implementation of nutrient management. Inputs of nitrogen to the site were manure fertilizer, commercial fertilizer, nitrogen in precipitation, and nitrogen in ground-water inflow; and these sources averaged 93, 4, 2, and 1 percent of average annual nitrogen additions, respectively. Outputs of nitrogen from the site were nitrogen in harvested crops, loads of nitrogen in surface runoff, volatilization of nitrogen, and loads of nitrogen in ground-water discharge, which averaged 37, less than 1, 25, and 38 percent of average annual nitrogen removals from the site, respectively. Virtually all of the nitrogen leaving the site that was not removed in harvested crops or by volatilization was discharged in the ground water. Applications of manure and fertilizer nitrogen to 47.5 acres of cropped fields decreased about 33 percent, from an average of 22,700 pounds per year (480 pounds per acre per year) before nutrient management to 15,175 pounds of nitrogen per year (320 pounds per acre per year) after the implementation of nutrient management practices. Nitrogen loads in ground-water discharged from the site decreased about 30 percent, from an average of 292 pounds of nitrogen per million gallons of ground water before nutrient management to an average of 203 pounds of nitrogen per million gallons as a result of the decreased manure and commercial fertilizer applications. Reductions in manure and commercial fertilizer applications caused a reduction of approximately 11,000 pounds (3,760 pounds per year; 70 pounds per acre per year) in the load of nitrogen discharged in ground water from the 55-acre site during the three-year period 1987–1990.  相似文献   

19.
The effects of increases in effective impervious area (EIA) and the implementation of water quality protection designed detention pond best management practices (BMPs) on storm runoff and stormwater quality were assessed in Gwinnett County, Georgia, for the period 2001‐2008. Trends among eight small watersheds were compared, using a time trend study design. Significant trends were detected in three storm hydrologic metrics and in five water quality constituents that were adjusted for variability in storm characteristics and climate. Trends in EIA ranged from 0.10 to 1.35, and changes in EIA treated by BMPs ranged from 0.19 to 1.32; both expressed in units of percentage of drainage area per year. Trend relations indicated that for every 1% increase in watershed EIA, about 2.6, 1.1, and 1.5% increases in EIA treated by BMPs would be required to counteract the effects of EIA added to the watersheds on peak streamflow, stormwater yield, and storm streamflow runoff, respectively. Relations between trends in EIA, BMP implementation, and water quality were counterintuitive. This may be the result of (1) changes in constituent inputs in the watersheds, especially downstream of areas treated by BMPs; (2) BMPs may have increased the duration of stormflow that results in downstream channel erosion; and/or (3) spurious relationships between increases in EIA, BMP implementation, and constituent inputs with development rates.  相似文献   

20.
ABSTRACT: A hydrologic investigation to determine vertical and seasonal variation of atrazine, alachlor, cyanazine, and nitrate at one location and to relate the variation to ground-water movement in the Iowa River alluvium was conducted in Iowa County, Iowa, from March 1986 to December 1987. Water samples were collected at discrete intervals through the alluvial sequence from the soil zone to the base of the aquifer. Alachlor, atrazine, and cyanazine were detected most frequently in the soil zone but also were present in the upper part of the alluvial aquifer. Alachlor was detected sporadically, whereas, atrazine, cyanazine, and nitrate were present throughout the year. In the alluvial aquifer, the herbicides generally were not detected during 1986 and were present in detectable concentrations for only a short period of time in the upper 1.6 meters of the aquifer during 1987. Nitrate was present throughout the alluvium and was stratified in the alluvial aquifer. The largest nitrate concentrations were detected in the middle part of the aquifer. Nitrate concentrations were variable only in the upper 2 meters of the aquifer. Vertical movement of herbicides and nitrate in the soil correlated with precipitation and degree of saturation. A clay layer retarded vertical movement of atrazine but not nitrate from the soil layer to the aquifer. Vertical movement could not account for the chemical variation in the alluvial aquifer.  相似文献   

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