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631.
陈祝青 《湖南环境生物职业技术学院学报》1997,(1)
水濂洞是南岳风景区系中的一个重要组成部分,本文就水濂洞景区的规划、设计和建筑提出了一些看法。指出在设计时,要重点突出:静、险、古、幽、奇五个特点。 相似文献
632.
It is usually inappropriate to define rectangular land areas or administrative units as the extent for quantifying landscapes
that possess hierarchical structure. As a functional unit established by geophysical relationships, the watershed is one of
many natural scales in the hierarchical landscape. We examined the dynamics of the Yashiro watershed of Japan at the landscape
level using pattern metrics based on Landsat thematic mapper (TM) imagery from 1985 to 1998. This watershed provides important
habitats for the hooded crane (Grus monachus), a vulnerable species. While its world population has remained stable, the number wintering at Yashiro has declined in recent
years. Changes in landscape metrics reveal that the spatial pattern within the watershed underwent homogenization due to depopulation
of local people and shifts in local energy requirements and forest management policy at Yashiro. Specific changes include:
a decrease in bare land area from 6.2% to 1.0% of the landscape, increased forest cover from 69.2% to 76.1%, reduction in
patch number from 1194 to 616 and enlarged mean patch size, and a decrease in total edge from 223,740 m to 158,040 m. The
rate of change in landscape metrics indicates a rapid change towards homogeneity in the landscape since 1990. The temporal
changes in hooded crane populations corresponded to the changes in landscape. An alternative explanation has been proposed
that decline of the species is influenced by landscape dynamics affecting both habitat selection and food resources. Conservation
at the watershed scale is suggested to be complementary to the current conservation measures of the species. 相似文献
633.
湿地价值分析及其基本原则 总被引:4,自引:0,他引:4
在对湿地功能、用途、属性与湿地价值间的关系、湿地价值的等级性进行分析的基础上,提出了湿地价值分析的基本原则,为在规划和决策时能充分考虑湿地的真正价值,从而实现湿地资源的保护与可持续利用。 相似文献
634.
Herzog F Lausch A Müller E Thulke HH Steinhardt U Lehmann S 《Environmental management》2001,27(1):91-107
This investigation tested the usefulness of geometry-based landscape metrics for monitoring landscapes in a heavily disturbed
environment. Research was carried out in a 75 sq km study area in Saxony, eastern Germany, where the landscape has been affected
by surface mining and agricultural intensification. Landscape metrics were calculated from digital maps (1912, 1944, 1973,
1989) for the entire study area and for subregions (river valleys, plains), which were defined using the original geology
and topography of the region. Correlation and factor analyses were used to select a set of landscape metrics suitable for
landscape monitoring. Little land-use change occurred in the first half of the century, but political decisions and technological
developments led to considerable change later. Metrics showed a similar pattern with almost no change between 1912 and 1944,
but dramatic changes after 1944. Nonparametric statistical methods were used to test whether metrics differed between river
valleys and plains. Significant differences in the metrics for these regions were found in the early maps (1912, 1944), but
these differences were not significant in 1973 or 1989. These findings indicate that anthropogenic influences created a more
homogeneous landscape. 相似文献
635.
陈盛彬 《湖南环境生物职业技术学院学报》1997,(1)
森林旅游资源的开发与利用是当今各国森林公园建设所面临的一个重要问题。本文就如何克分利用森林旅游资源,发挥森林景观优势开展多种旅游项目,提出了自己的看法与对策,为发展我国旅游业提供了理论依据。 相似文献
636.
C. Edwin Young 《Journal of the American Water Resources Association》1984,20(2):163-166
ABSTRACT: The impact of degraded water quality on the value of seasonal homes adjacent to St. Albans Bay on Lake Champaign in northern Vermont is estimated using hedonic price functions. The Value of properties located adjacent to the bay are depressed by about 20 percent, or $4,500 on average, compared with similar nearby properties on the larger but cleaner lake. Water quality degradation resulted in decressed property values of approximately two million dollars in the area surrounding the Bay. 相似文献
637.
Thomas A. More James R. Averill Thomas H. Stevens 《Journal of environmental management》1996,48(4):397-409
Several categories of non-market value have been identified for forests and other natural environments: use value, option value, altruism, bequest value, existence value and intrinsic value. In this paper, we view these values from a psychological perspective. Non-market values arise because natural resources play important roles in furthering human goals. This goal perspective contrasts with intrinsic value—the idea that natural objects have value as ends in themselves regardless of their relationship to man. Because of the lack of precise definitions, elements of intrinsic value are often mixed with existence value, creating confusion in the literature. These resource values need to be examined on a logical as well as an empirical basis. We argue that careful scrutiny reveals problems with both existence value and intrinsic value so that it is important to question their role in policy formation and analysis. 相似文献
638.
水资源价值量核算的初步构想 总被引:3,自引:0,他引:3
张志乐 《中国人口.资源与环境》1995,5(3):46-51
本文根据水资源的特点,阐述了水资源价值量核算的目的意义,分析了水资源价值量核算的基本原则,提出了进行水资源价值量核算的理论和方法的初步构想。 相似文献
639.
Gary Comstock 《Journal of Agricultural and Environmental Ethics》1990,3(2):114-146
Should we continue to support publicly funded research on genetically engineered herbicide resistant crops? In Part One, I discussed the difference between science and ethics, presented a brief history of weed control, and explained three moral principles undergirding my environmentalist perspective. I then argued that unqualified endorsement (E) of the research is unjustified, as is unqualified opposition (O). In Part Two, I argue against qualified endorsement (QE), and for qualified opposition (QO). 相似文献
640.
ABSTRACT: The impact of floodplain regulations on mean appreciation rates of residential land values was tested at six study areas in five counties in western Oregon. The study hypothesis that such regulations significantly depress appreciation rates of regulated lands relative to those of similar unregulated lands was in most cases rejected. When the hypothesis was accepted circumstances would render conclusions tenuous. The problems and issues facing this type of research are presented in case studies of two of the research study areas. The following factors challenge investigators seeking to resolve questions about the relationship between land use regulations and land values: varying degrees of stringency with which regulations are enforced; unequal assessment procedures between counties; influences external to floodplain regulations that may affect appreciation rates, including denial of permits for septic tanks, flood damages, and amenity values associated with waterfront locations; and the uncertain effect that the availability of flood insurance, which accompanies floodplain regulations, has on land values. 相似文献