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961.
通过对旅游者旅游资源环境感知调查、态度分析,能了解旅游者对风景区的满意度,对于促进当地旅游业的可持续发展具有极其重要的作用和意义。以五泉山风景区为例,结合实地问卷调查与访谈的方法,研究旅游者对五泉山风景区的环境感知,结果显示:旅游者对五泉山风景区旅游环境总体环境感知一般;对五泉山风景区的自然环境呈正面、积极感知,但是对饮食服务水平、旅游从业者服务态度、文化特色、环境设施等持保留态度;旅游者对在风景区内的环保责任和行为都表现出了积极的态度;旅游者对景区的忠诚度一般;地方政府在环境保护和旅游规划方面应当更有所作为。  相似文献   
962.
三峡地区农业经济监测原理与方法研究   总被引:2,自引:0,他引:2  
提出了经济系统抟动监测原理,认为受扰动X作用的系统S的特征指标(监测指标)O的变化量△O分为由系统S自身发展引起的变化量△O和由扰动X的作用引起的变化量△Ox,即△O=△O+△Ox,监测的目的是考察由扰动X引起的指标O的变化量△Ox,提出了建立经济系统监测指标体系。针对5项原则和三峡地区农业经济指标体系。针对不同系统特点和扰动特性,提出8种监测方法。以对三峡库区秭归县水田坝乡眩坝区域柑桔产业开发对  相似文献   
963.
为应对洪涝、新冠肺炎疫情等突发灾难,提出供应物资满足率最大、供应时间最短、供应成本最低的离散时间马尔科夫链-多目标规划模型(DTMC-MOP),动态地识别、分析、应对应急供应链风险;采用改进自适应NSGA-Ⅱ算法求解优化模型,并通过标准测试函数进行测试与评价,验证模型的可行性和有效性;通过算例分析,获得精度更高、分布更均匀的Pareto最优前沿。研究结果表明:决策者可以依据应急管理核心目标或不同偏好选择相适应的应急方案,研究结果可为应急供应链决策优化提供1种科学方法,对保障灾民生命安全、维护社会和谐稳定具有积极意义。  相似文献   
964.
Ecosystems are essential in providing multiple services to society. However, understanding ecosystem services (ESS) in terms of spatial distribution and trade-offs still remains a challenge for landscape planners and natural resource managers. In this paper, we analyzed the supply of a set of ESS – carbon storage, soil erosion protection, biodiversity, and recreation – within the landscape surrounding the city of Bari in Southern Italy. Through an analysis of this landscape, which includes natural protected areas, such as Natura 2000 Network sites, national and regional parks and nature reserves, and in view of the recent Fitness Check of the Nature Directives, we aimed to provide answers to the following questions: (i) Where are the areas of high and low supply of individual ecosystem services located?; (ii) Where do ecosystem service trade-offs (i.e., ‘hotspots’ and ‘coldspots’) occur?; and (iii) To what extent are ecosystem service hotspots and coldspots located within or outside of natural protected areas? Results show that most of the landscape in the study area supplied at least one of the selected ESS and that ESS hotspots were mostly located within forested and/or natural areas. Hotspots occupied 8.0% of the total landscape, with 23.7% located in natural protected areas. Coldspots were scarce and equal to 2.4%; they constituted only 0.1% of natural protected areas. Almost all of the landscape (89.6%) consists of intermediate areas (i.e., between hotspots and coldspots); 76.2% of natural protected areas consists of intermediate areas. This latter finding is relevant because the high intermediate classes are potentially high-performing areas, which lie mainly on the borders of protected spaces; they can positively influence ecological processes and thus enhance a wide-ranging provision of ESS. Our results highlight the importance of analyzing landscapes to facilitate the selection of priority areas where management efforts would yield maximum benefits.  相似文献   
965.
ABSTRACT: Stream order systems provide useful classification methods according to the number of tributaries collected. In urban catchments, sewer line order is a concepot concept providing for the same type of classification. Horton's stream order system is used to classify sewers beginning with the smallest lines as first order to the largest main sewer which is sixth order for two catchments studied. Average tributary area, average length and number of lines are shown as functions of order. The bifurcation ratios are also presented. They can be used for finding the number of sewer lines in the next order. The number of first order lines depend on lot size and the bifurcation ratios vary widely.  相似文献   
966.
ABSTRACT: ERTS-1 satellite imagery has been evaluated as a means of providing useful watershed physiography information. From these data physiographic parameters such as drainage basin area and shape, drainage density, stream length and sinuosity, and the percentage of a watershed occupied by major land use types were obtained in three study areas. The study areas were: (1) Southwestern Wisconsin; (2) Eastern Colorado; and (3) portions of the Middle Atlantic States Using ERTS-1 imagery at 1:250,000 and 1:100,000 scales it was found that drainage basin area and shape and stream sinuosity were comparable (within 10%) in all study areas to physiographic measurements derived from conventional topographic maps at the same scales Land use information can be usefully extracted for watersheds as small as 30 mi2(78 km2) in area. Improved drainage network and density information is obtained from ERTS-1 imagery in dissected areas such as Southwestern Wisconsin, but in heavily vegetated areas (Middle Atlantic States) or areas with little physical relief (Eastern Colorado) low order streams are difficult to detect and the derived drainage densities are significantly smaller than those obtained from standard maps. It is concluded that ERTS-1 imagery can be employed to advantage in mean annual runoff prediction techniques and in providing or maintaining land use information used in the calibration and operation of watershed models.  相似文献   
967.
Protected Area (PA) management is a complex issue that requires the consideration of many factors and relationships. A conceptual framework for the analysis of biodiversity change, local human communities, and PA management was put forward, accordingly. Under the framework, we investigated the economic status, livelihood activities, biodiversity use and perceptions of local communities, and the land use history in Wolong Biosphere Reserve, southwestern China through household survey and document review in order to gain a better understanding of the complexity of PA management. According to the land use history, the preservation of agro-biodiversity, and the raising of productivity, ecological rehabilitation and the regulation of the human pressures are indispensable in the management of the reserve. Livelihood activities and the perceptions of local communities were largely determined by the socioeconomic background, which has important implications in solving the conflicts or incompatibilities in the reserve. In Wolong Biosphere Reserve, it is beneficial to support local farmers in solving their socioeconomic problems such as the overabundance of labor force and the lack of livelihood alternatives. Without this, there will be scarcely any effective biodiversity conservation and successful reserve management in the long term.  相似文献   
968.
梁栋栋  陆林 《资源开发与市场》2004,20(3):211-212,215
通过对贫困地区旅游开发过程中土地利用变化的分析,提出了土地利用变化的驱动力和评价原则,并根据旅游地生命周期理论,对未来土地利用的趋势和方向进行了分析,同时指出在开发旅游时应注意的问题.以安徽省舒城县百丈岩旅游区为例,在分析旅游开发可行性的基础上提出了本区的旅游发展战略,最后分析了旅游开发对土地利用结构变化的影响.  相似文献   
969.
综放工作面采空区区域划分实用性分析   总被引:2,自引:0,他引:2  
随着综采放顶煤技术的进一步推广.采空区自燃理论纷纷兴起.由于受各自立场和条件限制,在现场实际应用过程中,这些理论常被误解误用,以致造成不必要的经济损失。为完善综放防灭火技术,更好地发挥理论的指导作用,根据多年的现场实践,研究总结出各自的适用条件,并使之形成一个完整的应用体系。即:1)在通常条件下,应用常规的“三带”理论或自燃新“三区”理论,以加快工作面回采推进速度,为防灭火措施的首选,但不能忽视均压(堵塞漏风通道)的作用;2)在特殊情形下(有尾巷或无旁侧采空区的综放面的回采初期),应用自燃四区理论,采用以堵塞漏风通道为主、加快回采推进速度为次的综合防灭火措施。  相似文献   
970.
本文提出了土地人口容力,即单位面积土地的人口容量的概念,建立了描述和测算开放区域人口容力的模型,确立了模型对多种人口容力定义,揭示了不同人口容力模型的内在联系性,并将它用于沪苏锡常城市群的土地人口容力测算和分析。  相似文献   
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