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911.
A Landscape Approach to Biodiversity Conservation of Sacred Groves in the Western Ghats of India 总被引:1,自引:0,他引:1
SHONIL A. BHAGWAT§ CHEPPUDIRA G. KUSHALAPPA† PAUL H. WILLIAMS‡ NICK D. BROWN 《Conservation biology》2005,19(6):1853-1862
Abstract: Although sacred groves are important for conservation in India, the landscape that surrounds them has a vital influence on biodiversity within them. Research has focused on tree diversity inside these forest patches. In a coffee-growing region of the Western Ghats, however, landscape outside sacred groves is also tree covered because planters have retained native trees to provide shade for coffee plants. We examined the diversity of trees, birds, and macrofungi at 58 sites—10 forest-reserve sites, 25 sacred groves, and 23 coffee plantations— in Kodagu district. We measured landscape composition and configuration around each site with a geographic information system. To identify factors associated with diversity we constructed multivariate models by using a decision-tree technique. The conventional measures of landscape fragmentation such as patch size did not influence species richness. Distance of sacred groves from the forest reserve had a weak influence. The measures of landscape structure (e.g., tree cover in the surroundings) and stand structure (e.g., variability in canopy height) contributed to the variation in species richness explained by multivariate models. We suggest that biodiversity present within sacred groves has been influenced by native tree cover in the surrounding landscape. To conserve this biodiversity the integrity of the tree-covered landscape matrix will need to be conserved. 相似文献
912.
城市景观生态建设──以沈阳市为例 总被引:7,自引:0,他引:7
李团胜 《城市环境与城市生态》1996,(3)
本文对城市进行了景观生态学分析,认为城市景观嵌块体小,数量多,景观高度破碎,道路廊道多,而缺少绿色廊道及绿色嵌块体,结合沈阳市,分析了景观质量及绿地现状,从而提出在城市景观生态建设中应增加绿色嵌块体及绿色廊道的数量。 相似文献
913.
Research on the development of the interrelationship between society and environment is crucial for the understanding of contemporary
landscapes. The West-Estonian archipelago provides an opportunity for such investigations because of its small size, landscape
diversity, and well-defined economic activities.
The contemporary landscapes of the islands reflect environmental changes resulting from centuries of human activity. This
paper describes both natural and human factors in the change in landscape of small Estonian islands during the last centuries.
During the period 1850–1940, human activity diversified the landscape structure. During World War II, with the establishment
of Soviet rule, the islets were depopulated; their landscape became more uniform and lost their economic and ecological vitality.
The re-establishment of private ownership of land and a market economy is predicted to result in positive changes in the landscape
of the islets. 相似文献
914.
The rise of the postwar environmental movement is rooted in the development of ecological consciousness within intellectual circles as well as the general public. Though many commentators cite the 1960s as the focal point of the new environmentalism, the ecological ethic had actually evolved by the 1930s in the writings and speeches of both scientists and public commentators. Agricultural conservationists led the way in broadcasting the message of ecology. Friends of the Land, an agriculturally-oriented conservation organization formed in 1940 and active through the 1950s, is an interesting example of how the agricultural community was an integral component in the rise of environmentalism. While Friends of the Land flourished only for a brief period, its goals and the ideas that the group represented illustrate how the ecological ethic was burgeoning by the early-1950s. Furthermore, the history of Friends of the Land is an important chapter in the ongoing quest for ecological agriculture and societal permanence. 相似文献
915.
A broad and objective perspective of ecological and socioenomic knowledge is required to underlie a scientific approach to
the problems of terrestrial restoration ecology. Uncertainty associated with limited scientific knowledge highlights the crucial
importance of the interaction between science and policy in weighing ecological restoration alternatives in relation to other
management options. In this paper, we provide a pragmatic definition for restoration ecology that is suitable for extensive
terrestrial applications and present a decision framework to help organize and clarify different phases of the decision process
as it is related to ecological restoration. We argue that restoration planning should include a wider spectrum of participants
and decisions than have traditionally been employed. 相似文献
916.
Joanne Heckman 《Environmental management》1985,9(2):141-149
The Cape Verde Islands originally supported a limited island ecology which, since the arrival of settlers 500 years ago, has been steadily altered or destroyed. Today, deforestation and overfarming, combined with the natural conditions of aridity and strong winds, have rendered the islands barren and eroded. The current government of the Republic of Cape Verde is attempting to alter traditional attitudes and customs of environmental neglect and mismanagement, while at the same time striving to restore or create self-sustaining ecosystems. The introduction of plants, animals, and physical structures enhancing soil and water conservation may create a more viable total ecosystem than existed before humans arrived. 相似文献
917.
Fred D. Theurer Ivan Lines Terry Nelson 《Journal of the American Water Resources Association》1985,21(1):53-64
ABSTRACT: This analysis relates physical-process, ecological, and economic models to: (1) analyze the instream water temperatures with respect to existing and proposed riparian vegetation under natural conditions; (2) use these water temperatures to determine salmon and steel-head fish populations that were based upon actual field count and known temperature preference data; and (3) determine the economic worth based upon the estimated carrying capacity of the river, the estimated number of return spawners, and the economic value of commercially caught and sport-caught salmon and steelhead. The economic evaluations are in accordance with procedures outlined by the U.S. Water Resources Council (1983). 相似文献
918.
Monica Goigel Turner 《Environmental management》1987,11(2):237-247
Land use since 1935 was quantified for Georgia, USA, and for a sample of 20 counties from the major physiographic regions within the state. Statistical data on crop production, pasture productivity, and forest growth were used to estimate net primary production. Appropriate harvest indices (ratio of crop yield to total plant production) were used to correct crop yield data for different decades. Net primary production (NPP) of the Georgia landscape increased from 2.5 to 6.4 tonnes/ha from 1935 to 1982, but varied considerably among land uses and physiographic regions. NPP in the piedmont and mountains reached a plateau between 1960 and 1982, but the upper and lower coastal plains showed a continued linear increase in NPP. In all regions, NPP rose most between 1960 and 1982, coinciding with increases in inputs such as fertilizer and irrigation. Natural ecosystem NPP for Georgia is approximately 16–18 tonnes/ha, and the estimated actual NPP is thus considerably less than the potential. Spatial and temporal patterns of NPP may be a useful basis for evaluating the biological performance of a landscape. 相似文献
919.
Since the beginning of the 1960s, mass tourism has been the most important menace to the environmental stability of fragile
and vulnerable Mediterranean microinsular systems. The socioeconomic changes introduced by tourism have produced important
variations in the use of resources, including land. The result usually has been an increase in the level of artificiality
of the territory, particularly in coastal areas. The intensity and frequency of change in the use of resources and the induced
changes in the level of artificiality may be used as an estimation of environmental stability. The northern area of Formentera,
Balearic islands, Spain, being the most environmentally important area of the island and simultaneously the most threatened
by mass tourism development, has been chosen as a study case. Forty types of vegetation and land use have been estimated and
mapped in the area. The stability level of each land use type has been estimated, before and after the development of tourism,
and the main environmental processes have been identified. An attempt is made to predict some future trends and their variations. 相似文献
920.
B. De Martis M. A. de Miranda Restivo A. Mocci Demartis E. Serra 《Environmental management》1992,16(3):381-388
Capoterra Pond in southern Sardinia is described and analyzed with respect to its morphological, meteorological, physical
and chemical characteristics, and its zoobenthic, zooplankton, and phytoplankton biocenoses. The birdlife, flora, and riparian
associations of vegetation are studied in order to draw international attention to the importance of this lagoon, the precariousness
of its ecosystem, the seriousness of current attempts to destabilize it, and the need to encourage the Sardinian authorities
to initiate conservation measures, especially as rare birds have found their niches there. 相似文献