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151.
可持续发展系统是一个由经济、社会、生态环境等要素构成的复杂系统。在崇明生态岛建设的背景下以区域可持续发展理论为指导,建立区域可持续发展综合评价指标体系,并选择了衡量可持续发展状态和特征的4个指数——可持续发展指数、持续度、协调度和趋势度来综合评价崇明岛的可持续发展能力,并在此基础上为崇明经济跨越式发展、社会功能的健全和生态环境可持续利用等目标的实现提供科学的预测和战略决策依据。结果表明,崇明岛可持续发展水平整体逐年提高,且上升的幅度呈上升的趋势。崇明岛可持续发展系统过去10年呈现明显的持续性。经济、社会、生态环境子系统之间的协调度较高,表现出高度的同步性,趋势度向更高的水平发展。得出的评价结果符合实际。  相似文献   
152.
海南是我国生物多样性最丰富的地区之一,也是我国经济发展最快的地区之一,努力在海南建立起可持续发展模式是寻求保护与发展并进的有效途径  相似文献   
153.
海岛旅游发展再一次成为海洋旅游业发展的新突破口.以湄洲岛为代表的文化型海岛凭借其深厚的文化内涵和优质的海滨旅游资源成为海洋旅游业发展的生力军.从解读文化型海岛内涵及特征入手,全面剖析了湄洲岛的优势条件,从文化价值、文化需求、文化生态、文化形态等方面深入挖掘湄洲岛所含文化特性,以此构建起湄洲岛善行旅游发展的“四和四共一发展”的互动效应,探寻出一条具有文化型海岛特点的湄洲岛善行旅游发展之路.  相似文献   
154.
--Hainan Island, located at the southern end of China, hasless than 0.4% of land area but contains 13% of plant and animalspecies in China. During the last four decades many primary forestshave been converted to shrub land, grassland, and tree planation(e.g., eucalyptus forest). As a result, area of primary tropicalforest has been reduced from 25.8% in the 1950s to 4% in the 1990s.To assess impacts of land conversion on plant and bird speciesdiversity, a series of samples in primary forest and four types ofconverted lands were took. The land conversion had tremendouslyreduced both plant and bird species diversity. Specifically, plantspecies richness per site was 83.7 in primary forest, 28.3 in shrubland, 12.5 in grassland, 14.4 in eucalyptus forest, and 21.4 inAcacia forest. Bird species richness showed a similar trend 22.0in primary forest, 14.5 in shrub land, 2.5 in grassland, 4.9 ineucalyptus forest, and 9.0 in Acacia forest. The Shannon speciesdiversity indices for plants in the five types of land cover were3.69, 1.99, 0.97, 1.47 and 2.07, respectively. Similarly, the Shannon indices for bird species diversity were the highest in primary forest, and lowest in grassland, and intermediate in shrubland and eucalyptus forest.  相似文献   
155.
1IntroductionLandcoverchangehasanincreasingimpactonforestecosystemsworldwide.Thedestructionofnativehabitatsisrecognizedasoneo...  相似文献   
156.
The impacts of economic forest on global environmental change(GEC) are one of the hot issues in environmental study. Based on the 3-year observation data and 40-year climate data, GEC and analysis of the hydrological dynamic characteristics of rubber plantations and estimate of the water balance in the rubber plantations in Hainan Island were made. The results showed that the rainfall intercepted by thecanopy of the plantations accounted for 11.4-5 % of the annual rainfall, the total runoff for 23.71%, the total evaporation and transpiration for 63.24%, the soil moisture storage for 1.6%. Analysis of the 40year rainfall data in the 19 counties of Hainan Island during 1951—1990 showed that the large-scale substitution of the natural vegetation with the rubber plantations had no significant effect on the local rainfall in Hainan Island. The main reasons are (1) 80% of the rainfall in Hainan is brought by typhoons; (2) the proportion of 11.6% rubberplantations in total forest coverage in Hainan is not enough to influence the local rainfall in Hainan Island; and (3) although the rubberplantation is artificial vegetation, it has the similar function to the tropical rain forest. Analysis of the total water resource and I‘otal GDP ofHainan in 1997 showed that the economic benefit resulted from the water resource was 1.0 RMB Yuan/m3 . The value of hydrological of therubber plantation in Hainan was 113.9 million RMB Yuan/a when compared with the tropical rain forest. The paper reaches conclusion that the hydrological eco-service function of rubber plantation has been enhanced after transformed from natural vegetation, which includes the natural service and powerful social service.  相似文献   
157.
从台湾岛基本地质特征出发,通过与大陆东南沿海及邻近地区之间的地质对比,提出关于台湾岛成因的新假说,即台湾岛是在晚中生代随着东南大陆的离散而逐渐分离出去的一个陆块,并经历逆时针旋转,于中新世以后在福建沿海与大陆碰撞拼贴.  相似文献   
158.
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   
159.
The effects of off-road vehicles (ORVs) on the dune system of Fire Island National Seashore, New York, USA, were examined through a detailed, two-year field study. The experimental approach was adopted in order to evaluate the environmental effects of ORVs in this zone. Adjacent control and impact sites were established in two locations. Vehicle impacts were applied at the equivalent rate of one vehicle pass per week. Monitoring of foredune vegetation through sequential quadrat surveys and construction of sea-ward limit maps showed a significant loss of vegetation resulting from ORV impacting. Loss of vegetation resulted in an alteration of the natural foredune profile, which could increase dune erosion during storm wave attack.  相似文献   
160.
The microclimate of beach and foredune areas of North Padre Island along the mid-Texas coast was found to be greatly modified by vehicular and pedestrian traffic during investigations made from late fall to early summer 1973–74. The primary effect of human activity on microclimate was expressed as reduced cover and species diversity of the vegetation. As the intensity of human activity increased, elevation, especially of areas near the beach, was decreased, whereas average wind velocities near the ground surface, evaporation, atmospheric salinity near the ground surface, wind-carried sand particles near the ground surface, soil salinity, soil pH, average soil temperature and range in temperature, soil bulk density, and soil-water contents were increased.  相似文献   
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