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1.
资源开发利用与可持续发展问题探讨   总被引:2,自引:0,他引:2  
本文在简介资源系统与资源开发概念的基础上,提出了资源开发的原则,并结合我国资源开发的限制因素,提出了开发措施。  相似文献   

2.
云山国家森林公园旅游开发可行性研究   总被引:2,自引:0,他引:2  
本文在充分调查的基础上,全面阐述了湘西南云山国家森林公园旅游开发的优越条件,指出了在旅游开发中存在的问题,提出了可行性开发的建议与初步设想,并对开发的前景意义进行了研究分析  相似文献   

3.
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   

4.
我国正处于页岩气开发的试验期,页岩气开发会带来水资源紧缺、水和土壤污染及甲烷泄漏等环境污染问题,因此,分析页岩气开发带来的环境问题并制定应对措施十分必要。文章详细分析了页岩气开发过程中可能引起的一系列问题,并结合我国页岩气开发实际情况提出了解决对策,希望能为我国页岩气的开发提供一定的参考。  相似文献   

5.
福建海洋资源的开发利用   总被引:1,自引:0,他引:1  
本文分析了福建省的海洋资源优势与开发现状,提出了海洋资源开发的指导思想与原则,探讨海洋产业的开发和空间布局  相似文献   

6.
乌苏里江国家森林公园开发建设探讨   总被引:2,自引:0,他引:2  
介绍了乌苏里江国家森林公园旅游资源概况 ,在确定公园开发建设原则的基础上 ,评价了公园的开发建设条件 ,并提出了公园开发建设措施。  相似文献   

7.
云南银杏产业的发展前景   总被引:8,自引:0,他引:8  
本文分析了国内外银杏资源的开发与市场状况,以及云南银杏开发与利用前景,提出了开发银杏产业的建议  相似文献   

8.
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   

9.
浅谈秦皇岛市旅游开发问题   总被引:2,自引:0,他引:2  
旅游开发导向模式由旅游资源和客源市场确定。对于旅游开发而言,导向模式的确定是关键,本文对秦皇岛市的旅游开发现状进行了分析,由此确定了导向模式,同时对旅游开发与保护的关系进行了探讨。  相似文献   

10.
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   

11.
ABSTRACT: Winterkill, the death of fish under ice due to oxygen deficiency, threatens hundreds of shallow lakes in the upper Midwest of the United States every winter. For decades, attempts have been made to prevent winterkill, usually through aeration, with mixed results. In large part, the failure of strategies to prevent winterkill can be linked to a lack of understanding of winter limnology and in particular, of oxygen dynamics under ice. Most winterkill lakes behave as closed systems with regard to oxygen. Consequently, the oxygen content of an ice and snow covered lake is essentially a function of the amount of initial storage and the rate of depletion. Should the stored oxygen be insufficient to prevent near anoxia before melting of the ice cover occurs, winterkill will result. Most oxygen consumption in ice covered lakes is due to bacterial respiration and chemical oxidation at the sediment/water interface, the remainder occurring in the water column. Oxygen consumption (and thus depletion) is a function of the velocity and oxygen concentration of the near sediment water. This is due to the fact that oxygen transport to the sediment is mediated by a diffusive boundary layer adjacent to the sediment surface. Winter oxygen depletion rates decrease when the oxygen concentration of the overlying water falls below about 3 mg/l. Aeration techniques which increase the oxygen concentration and velocity of the near-sediment water also increase the oxygen consumption (depletion) rate.  相似文献   

12.
The functions of packaging are derived from product requirements, thus for insight into the environmental effects of packaging the actual combination of product and package has to be evaluated along the production and distribution system. This extension to all related environmental aspects adds realism to the environmental analysis and provides guidance for design while preventing a too detailed investigation of parts of the production system. This approach is contrary to current environmental studies where packaging is always treated as an independent object, neglecting the more important environmental effects of the product that are influenced by packaging. The general analysis and quantification stages for this approach are described, and the currently available methods for the assessment of environmental effects are reviewed. To limit the workload involved in an environmental assessment, a step-by-step analysis and the use of feedback is recommended. First the dominant environmental effects of a particular product and its production and distribution are estimated. Then, on the basis of these preliminary results, the appropriate system boundaries are chosen and the need for further or more detailed environmental analysis is determined. For typical food and drink applications, the effect of different system boundaries on the outcome of environmental assessments and the advantage of the step-by-step analysis of the food supply system is shown. It appears that, depending on the consumer group, different advice for reduction of environmental effects has to be given. Furthermore, because of interrelated environmental effects of the food supply system, the continuing quest for more detailed and accurate analysis of the package components is not necessary for improved management of the environmental effects of packaging.  相似文献   

13.
ABSTRACT: The geochemistry and nature of the flow of ground water not only control the supply potential but constitute clues to the whole geology of an area. A study has been made of the largest available assemblage of data from 161 wells for the Island of Montreal collected by the Geological Survey of Canada in 1951–53. Data indicated that the system is generally subartesian, flowing from the principal topographically high areas towards the shores of the Island. As the probable use is about 13% of the estimated recharge of 140 million liters per day, most wells could be supplied by local recharge. The study has confirmed the predominance of calcium bicarbonate ground water from the carbonate sequence. The waters appeared to be saturated with respect to CaCO3 in all but 10 wells. The presence of other types of waters suggests the effects of the igneous intrusions of the area, the post-glacial marine submergence and the upward movement of waters from deep sources through fault and other structural zones. Confirmation of the significant variations in chemical composition in some neighboring wells indicated the future need for repetitive sampling from specific horizons for chemical and isotopic analyses.  相似文献   

14.
Brown, Juliane B., Lori A. Sprague, and Jean A. Dupree, 2011. Nutrient Sources and Transport in the Missouri River Basin, With Emphasis on the Effects of Irrigation and Reservoirs. Journal of the American Water Resources Association (JAWRA) 47(5):1034‐1060. DOI: 10.1111/j.1752‐1688.2011.00584.x Abstract: SPAtially Referenced Regressions On Watershed attributes (SPARROW) models were used to relate instream nutrient loads to sources and factors influencing the transport of nutrients in the Missouri River Basin. Agricultural inputs from fertilizer and manure were the largest nutrient sources throughout a large part of the basin, although atmospheric and urban inputs were important sources in some areas. Sediment mobilized from stream channels was a source of phosphorus in medium and larger streams. Irrigation on agricultural land was estimated to decrease the nitrogen load reaching the Mississippi River by as much as 17%, likely as a result of increased anoxia and denitrification in the soil zone. Approximately 16% of the nitrogen load and 33% of the phosphorus load that would have otherwise reached the Mississippi River was retained in reservoirs and lakes throughout the basin. Nearly half of the total attenuation occurred in the eight largest water bodies. Unlike the other major tributary basins, nearly the entire instream nutrient load leaving the outlet of the Platte and Kansas River subbasins reached the Mississippi River. Most of the larger reservoirs and lakes in the Platte River subbasin are upstream of the major sources, whereas in the Kansas River subbasin, most of the source inputs are in the southeast part of the subbasin where characteristics of the area and proximity to the Missouri River facilitate delivery of nutrients to the Mississippi River.  相似文献   

15.
以协商的方式确定水污染物间接排放标准的规定打破了人们对标准确定性、强制性的传统认识。协定标准的优势在于充分利用污水处理厂的污水处理能力,减轻企业的污水处理负担,使企业可以集中力量搞生产。协定标准具有灵活性和优越性,应充分利用。通过对协定标准概念和重要性的分析,指出协定标准存在效力不确定、缺少对协定范围的限制等问题,造成协定标准在实践中通常被忽视或者滥用。并从明确协定标准的范围、加强排污企业的管理和协定标准的监督等方面,进一步提出了限制和完善水污染物间接排放标准的建议。  相似文献   

16.
Caves can be difficult to navigate and often require physical modification to allow easy access for visitors. Single entrance caves double the access impact of each visitor. Visitors in tourist caves have direct physical effects such as the introduction of concrete and steel structures; transport of mud, dust, and nutrients; installation of lights and the exhalation of water vapour and carbon dioxide into the air. Indirect physical effects include alteration of the microclimate, both through physical modifications that change the ventilation regime and through the presence of visitors leading to changes in temperature, humidity and CO2 within the cave environment. Anthropomorphic changes to cave physical environments to aid access or to reduce backtracking can have adverse effects on the internal microclimate of cave systems with subsequent changes to the cave environment affecting the quality of decorations and cave art and the diversity of cave fauna. Although often stated that caves operate at or near a constant temperature, closer examination indicates that cave temperatures are neither static nor constant. The degree of variation depends largely on the structure and physical characteristics of the cave. Air temperature and humidity gradients between the inside and outside cave environment can result in air density differences, which create airflow, which will in turn affect the cave microclimate. As part of the development of a management framework for King Solomons Cave, Tasmania, a study of the microclimate was carried out on behalf of Tasmanian Parks and Wildlife Service. Analysis of the variables showed significant differences in air temperature within each site and between sites. These differences range from 4 degrees C variation at one site to 0 degrees C at another site. The data were used to model potential airflow between the cave and the external environment. Results indicate that part of the cave is dominated by airflow between the chimney and the cave entrance leading to microclimatic fluctuations, while stable climatic conditions occur at the end of the cave. Future management strategies that propose a passage from the chamber to the surface via the current end zone would create a potential for airflow induced microclimatic change, leading to a change in both the temperature and moisture regimes, necessitating the construction of an airtight double door system.  相似文献   

17.
底泥的氮、磷释放及其微生物影响的研究   总被引:2,自引:0,他引:2  
张恒军  吴群河 《环境技术》2003,41(Z1):20-23
氮和磷在自然界的循环已经引起了人们的关注,一方面因为氮和磷是生态系统中必不可少的营养元素,另一方面过剩的氮和磷会导致水域的富营养化 ,从而使生态平衡遭受破坏.本文综述了水体沉积物中氮和磷受微生物作用进行释放的影响,以及国内外的研究历史和现状.总结了氮磷微生物代谢的特点,并阐述了与传统认识相区别的最新发现和思想.本文试图从理论上说明微生物的氮磷释放机理,通过生物化学和分子动力的角度解释了细菌对氮磷的吸收和释放,即质子动势理论和Pho调控理论.目前,这一领域研究的热点是为了特殊的使用用途对于高效微生物的分离鉴别和组合培养,和对氮磷代谢的影响因素.  相似文献   

18.
Histopathological and histochemical variations in non-specific esterases of the intestinal epithelial lining of the earthworm (Pheretima elongata), exposed to a single field dose of the herbicide glyphosate, were studied on the first, second, third, and fourth week of exposure. A severe cell death was observed in the intestine during the first and second weeks of exposure and mortality exceeded 50 percent. In the third week of exposure, the cells of the intestinal lining of the worms which had survived started regenerating and in the fourth week of exposure the epithelial lining regained its original characteristics and architecture, suggesting the high regenerative power of earthworms. Non-specific esterases showed an intense activity in the first week of the exposure and then decreased in the second week to nearly a minimum, where the entire cell structure was lost. However, the activity of the enzyme remained low until the third week where there was a small rise in the activity, and was confined to certain places in the cytoplasm. In the fourth week, almost a complete regeneration of the epithelial lining as well as the non-specific esterases activity was observed and became quite similar to that of the control worms. These results suggest that glyphosate, even at the recommended field dose, could cause cell death and interfere with non-specific esterases activity of the epithelial lining of the intestine of P. elongata causing at least 50 percent mortality in the population of the worms.  相似文献   

19.
The fisher (Martes pennanti) has recently recovered from historic extirpations across much of its geographic range. There are at least five explanations for the recovery of the fisher, including changes in the amount of habitat, the suitability of habitat, trapping pressure, societal attitudes toward predators, and climate. We evaluated a recovering fisher population in Ontario to test two conditions we viewed as necessary to support the hypothesis that fisher populations have increased due to an increase in the amount of forested land. First, we tested whether the amount of forested land has increased. Second, we tested whether contemporary fisher abundance (and therefore habitat quality) was related to the amount of forest. Topographic maps showed that the proportion of forested land in the study area had increased by 1.9% per decade since 1934 and 3.3% per decade since 1959, likely as a result of land conversion from agricultural uses. Overall the proportion of the study area that was forested increased from 29% to 40% during 1934 to 1995. Census data from the region indicated that there had been a decline in the amount of land area being farmed during the last 50 years. Recent livetrapping data showed that fisher abundance was positively related to the proportion of landscapes that were forested. Based on our results, we could not reject the hypothesis that an increase in the amount of forested land has contributed to the recovery of fisher populations.  相似文献   

20.
A tsunami, triggered by a massive undersea earthquake off Sumatra in Indonesia, greatly devastated the lives, property and infrastructure of coastal communities in the coastal states of India, Andaman and Nicobar Islands, Indonesia, Sri Lanka, Malaysia and Thailand. This event attracted the attention of environmental managers at all levels, local, national, regional and global. It also shifted the focus from the impact of human activities on the environment to the impacts of natural hazards. Recovery/reconstruction of these areas is highly challenging. A clear understanding of the complex dynamics of the coast and the types of challenges faced by the several stakeholders of the coast is required. Issues such as sustainability, equity and community participation assume importance. The concept of ICZM (integrated coastal zone management) has been effectively used in most parts of the world. This concept emphasizes the holistic assessment of the coast and a multidisciplinary analysis using participatory processes. It integrates anthropocentric and eco-centric approaches. This paper documents several issues involved in the recovery of tsunami-affected areas and recommends the application of the ICZM concept to the reconstruction efforts.  相似文献   

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