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1.
中国典型自然保护区生境状况时空变化特征   总被引:17,自引:1,他引:16  
祝萍  黄麟  肖桐  王军邦 《地理学报》2018,73(1):92-103
中国已建立各类自然保护区2740个,占全国陆地面积的14.8%。本文以典型国家级自然保护区为例,基于遥感反演、模型模拟、空间分析等方法,获得植被覆盖度、净初级生产力(NPP)和土地覆被时空数据集,分析2000-2015年中国不同区域、不同类型自然保护区生境状况时空变化及人类扰动的影响,进而评估自然保护区在栖息地及生物多样性保护方面的效果。结果表明:2000-2015年,国家级自然保护区植被覆盖度从36.3%提高到37.1%,各类型自然保护区均有不同程度提高,其中森林类保护区年增速0.11%,草原草甸类0.84%,内陆湿地类0.21%,荒漠生态类0.09%,野生动物类和野生植物类则分别为0.11%和0.08%。草原草甸类、内陆湿地类、荒漠生态类、野生动物类自然保护区植被NPP年增速分别为2.06 g·m-2、1.23 g·m-2、0.28 g·m-2、0.4 g·m-2,而森林类和野生植物类则分别以3.45 g·m-2和2.35 g·m-2的年速率减少。近15年,国家级自然保护区内人类扰动呈现微弱变化,除青藏高原区和南亚热带湿润区内保护区人类扰动略微下降以外,其他区域均有所增强,特别是北亚热带和温带湿润区,其保护区人类扰动由4.70%明显增至5.35%。  相似文献   

2.
The relationship between trajectories of forest cover change and fragmentation due to physical and anthropogenic activities in Sariska Tiger Reserve is addressed in the article. The authors conducted a field visit to the reserve to collect groundtruth data and perform a village survey. Thereafter, their main method consisted of using Landsat TM images for three days, one in each of the years 1989, 1994, and 2014, to assess spatial-temporal variation in forest cover. A fragmentation model was used to examine the extent and pattern of forest degradation. The results showed an overall increase in forest cover in Sariska Tiger Reserve from 53% in 1989 to 55% in 2014. However, the fragmentation statistics revealed a deterioration in forest health. There was an increase in the fragmentation categories perforated, edge, and patch in their respective areas, while the core areas decreased at the expense of other fragmentation classes. The existence of villages, roads, and pilgrimage sites had increased the pace of degradation and fragmentation of forest in the reserve. The authors conclude that the fragmentation model was effective for analysing forest degradation and identifying the priority areas for strategic planning of nature conservation.  相似文献   

3.
The Sundarban Biosphere Reserve in West Bengal, India, is part of the largest mangrove forest ecosystem in the world. The reserve is a world heritage site and the last refuge for the endangered Bengal tiger at a crucial time when global climate change threatens their existence. The mangrove ecosystem and wildlife conservation have become the priority for the state government of West Bengal. However, in becoming so, the state government imposes restrictions on catching fish in the core and buffer areas of the biosphere reserve, which intensify fishermen's everyday resource‐access struggles in the mangrove forest. This paper examines the conflict between local fishermen and conservation needs, broadening the understanding of human‐environment relationships in the Sundarbans region of India.  相似文献   

4.
Finnland     
The forest limits of south-east Norway have expanded to higher altitudes. Two main processes are believed to cause these changes: regrowth after abandonment of human utilisation and recent climate changes. The article aims at separating the effects of these two processes on the upper forest limits and recent forest expansion. Four datasets representing 161.5 km2 have been used: climate data, downscaled climate change scenario data, forest height growth, and four vegetation maps. The maps represent the years 1959 and 2001, potential natural vegetation (PNV), and a climate change scenario (CCS). The recent upper potential climatic and edaphic forest limit (UPCEFL) was used to define the potential for forest regrowth after the abandonment of human utilisation. Forest height growth and climate data were then used to analyse any supplementary effect of recent climate change. The projected future forest limits were based on the IPCC IS92a scenario for 2020–2049. The results show that raised forest limits and forest range expansion often attributed to recent climate change is rather the product of regrowth, a process that was climatically retarded from 1959 to 1995. For the period 1995–2006, the data indicate a preliminary effect of climate change escalating the regrowth and probably pushing the future forest limits to higher altitudes.  相似文献   

5.
The subtropical Atlantic Forest is a highly diverse ecosystem in South America and one of the most endangered rain forests in the world. The present study focuses specifically on the Paraguayan part of the tri-national Atlantic Forest. Over the last decades, the Paraguayan Atlantic Forest presented one of the highest deforestation rates in the world, and today, only a small share remains. Hence, forest loss in Paraguay's Atlantic Forest was detected and analysed through remote sensing and GIS methodologies based on Landsat images obtained in 2003 and 2013. The objective of this study was to examine the spatial impact of forest loss in Paraguay's Atlantic Forest over the past decade with a special focus on biodiversity conservation. Classifications results obtained overall accuracies above 83% and revealed that over 6000 km2 of forest was cleared during the study period. The forest landscape and its fragmentation level were characterised through a set of landscape metrics, in particular the proximity analysis which support the identification of forest priority areas for nature conservation and potential biological corridors. In summary, the study revealed that deforestation and fragmentation of the Atlantic Forest area continued, but at a slower pace than that in the previous decade. Protected areas were conserved very effectively; however, forest core areas without any protection status require further attention. Intact forest patches and their connectivity are a crucial prerequisite to biodiversity conservation in a highly fragmented forest area. The combination of different remote sensing and GIS methods provides valuable information for sustainable forest management in the region.  相似文献   

6.
ABSTRACT

It is commonly assumed that personal experiences of a changing climate will influence people’s attitudes to the extent that they will be more likely to acknowledge anthropogenic climate change as a real threat and therefore be more willing to accept both mitigation and adaptation efforts. In the article, the authors examine how survey participants’ personal experiences of extreme events and climate-related changes in the natural environment influenced their perceptions of climate change. Using data from a nationally representative survey conducted in Norway in 2015 and the results of logistic regressions, the authors find that individual observations of changes in nature were linked to higher levels of concern with regard to climate change, as well as to attitudes that were more positive towards personal mitigation and adaption efforts. Somewhat counter-intuitively, they also find that participants who had personally experienced a natural hazard event were less concerned about climate change compared with participants without such experiences. The authors conclude that personal experience of the consequences of climate change may in some cases have a limited effect on enhancing people’s concerns about climate change.  相似文献   

7.
长白山自然保护区旅游资源开发的生态环境影响及其保护   总被引:21,自引:3,他引:18  
朱颜明  王宁 《山地学报》1999,17(4):353-357
长白山自然保护区属世界自然保留地之一的国家级森林和野生动物类型自然保护区。它以其自然资源绚丽,生物种源丰富,生态系统完整享誉全世界。曾以独特的“天然”“原始”状态,成为环境背景研究监测的理想场所,旅游资源开发带来明显的经济效益,同时也造成保护区的环境污染和生态破坏,保护区内开展旅游必须遵循适度开必,合理保护的原则,强调生态旅游,妥善处理保护与开发的关系,应尽快制定自然保护区环境规划,进行有效环境综  相似文献   

8.
本文评价了三江源自然保护区生态系统宏观结构及涵养水源、保持水土、保护生物多样等主要生态服务功能,分析了自然保护区生态保护与建设工程的生态成效及其原因。结果显示,工程实施后,各自然保护区的土地覆被转类指数明显增加,生态系统宏观状况好转;保护区内草地生产力皆呈增加趋势,水域面积增加,食物供给能力提高,栖息地生境好转。森林类保护区的森林面积减少趋势得到遏制;湿地类保护区的湿地面积多呈增加趋势;草地类保护区的草地减少趋势缓解,荒漠化明显遏制,草地植被覆盖度有所增加;冰川类保护区多条冰川出现明显退缩导致冰川融水增多,有利于雪线以下草地净初级生产力的增加。  相似文献   

9.
Measuring land-use, land-cover change in biodiverse, tropical countries is critical for conservation management and sustainable planning because it provides quantifiable data regarding broad environmental changes. This project uses Landsat satellite imagery to document vegetation cover change on Ambergris Caye, Belize, from 2000 to 2017. The close proximity of the Belize Barrier Reef Reserve System has made Ambergris Caye the most popular tourist destination and economic hub in Belize. As a result, the region has undergone intense commercial and residential development coupled with rapid population growth over the past two decades. Understanding general trends in landscape dynamics is critical for the natural resource–based tourism industry of Belize to continue to thrive. Unsupervised classification methods and a per pixel postclassification comparison were used with Landsat imagery to estimate loss in vegetation cover and increases in urban and barren land. The results indicate a 10.85 percent decrease in vegetation and a 39 percent increase in urban and barren land during the seventeen-year study period with an annual forest loss rate of 0.67 percent per year using a compound interest rate formula. The results of this analysis represent a baseline study of vegetation change on Ambergris Caye to inform management and conservation efforts.  相似文献   

10.
This article combines approaches to better understand both forest cover changes and attitudes toward environmental conservation in the El Cielo Biosphere Reserve in northeastern Mexico. Satellite images are used to document the extent and response of forest cover in the reserve before and after its designation as a biosphere reserve. Ethnographic interviews are also employed to examine the attitudes of local people toward the costs and benefits of the biosphere reserve in their lives. Our research found that unlike many “paper parks,” large-scale deforestation has stopped and forest cover has expanded after the biosphere reserve was created. Our research also found that local people value both tangible and intangible benefits created by the biosphere reserve.  相似文献   

11.
We examined change in areal extent of mountain meadows and fields of deciduous shrubs and conifer saplings in the central western Cascade Range of Oregon, based on analysis of aerial photographs taken in 1946 and 2000. These nonforest vegetation patches are distinctive habitats in dominantly forested landscapes, such as the Cascades, and change in extent of these habitats is of interest to scientists and land managers. We mapped and dated even-aged forest stands of probable postfire origin around the nonforest patches, using tree-ring analysis and interpretation of aerial photographs. We used these and archival data to interpret possible influences of past wildfire and sheep grazing on the extent of nonforest patches. The total area of nonforest vegetation patches decreased from 5.5 percent of the study area in 1946 to 2.5 percent in 2000. Significantly more cases of contracted patches were observed for mesic and xeric meadows which have adjacent forest established after wildfire in the approximately 150 years preceding 1946. A higher proportion of mesic (47 percent, n = 47) than xeric (17 percent, n= 115) meadows contracted between 1946 and 2000. Broad-leaved shrub fields were unchanged, probably because of topo-edaphic controls, dense cover of shrubs, and snow effects; but all fields of conifer saplings underwent succession to forest. We observed no strong influences of sheep grazing on the extent of meadows.  相似文献   

12.
ABSTRACT

The abstract classification system Nature in Norway (NiN) has detailed ecological definitions of a high number of ecosystem units, but its applicability in practical vegetation mapping is unknown because it was not designed with a specific mapping method in mind. To investigate this further, two methods for mapping – 3D aerial photographic interpretation of colour infrared photos and field survey – were used to map comparable neighbouring sites of 1 km2 in Hvaler Municipality, south-eastern Norway. The classification accuracy of each method was evaluated using a consensus classification of 160 randomly distributed plots within the study sites. The results showed an overall classification accuracy of 62.5% for 3D aerial photographic interpretation and 82.5% for field survey. However, the accuracy varied for the ecosystem units mapped. The classification accuracy of ecosystem units in acidic, dry and open terrain was similar for both methods, whereas classification accuracy of calcareous units was highest using field survey. The mapping progress using 3D aerial photographic interpretation was more than two times faster than that of field survey. Based on the results, the authors recommend a method combining 3D aerial photographic interpretation and field survey to achieve effectively accurate mapping in practical applications of the NiN system.  相似文献   

13.
上海自然植被的特征、分区与保护   总被引:17,自引:0,他引:17  
高峻 《地理研究》1997,16(3):82-88
上海地区有种子植物约134科510属919种。种子植物的分区类型共15°个,其中泛热带分布、北温带和东亚分布各占总属数的27.8%、21.6%和11.9%.地带性植被以常绿阔叶林和常绿落叶阔叶混交林为主,其中红楠群落和青冈栎群落能较好地反映中亚热带的植被和环境特征。非地带性植被以潮间带植被和水生植被为主。上海自然植被的类型和分布规律反映了本区地处中亚热带向北亚热带过渡地带的气候特征以及濒江临海的环境特点。同时其现状也表明了上海的自然植被处于不断增长的压力之下所发生的变化,因此亟需加以保护。上海的植被区划可分为隶属于北亚热带常绿落叶阔叶林地带的河口沙洲植被区,碟缘高地植被区和东北淀泖低地植被区,以及隶属于中亚热带常绿阔叶林地带的西南丘陵、低地植被区等。  相似文献   

14.
Loss of biological diversity is among the most pressing environmental problems facing modern societies. Whereas today much is known about peoples' opinions on climate change, there is still a lack of knowledge regarding how people asses the issue of biological diversity. The article represents a step towards a better understanding of public opinions on the issue of biodiversity, and hence also of the prerequisites and possibilities for a more or less vigorous or legitimate policy on this issue. The analyses show that social background matters for concern about biodiversity, but only to a certain extent: women are less negative towards biodiversity protection than men, the older segments of the population, at least in Norway, are less concerned with biodiversity, and education has only a marginal effect. Hence, to a large extent, political attitudes matter and indicate that concern for biodiversity seems to work by various types of available heuristics whereby a given case is linked to political understandings of other and similar and/or familiar issues. The inclusion of other political variables (local decision-making) and what the authors label ‘cultural variables’ (e.g. view of nature and trust in science) seem also to matter decisively for attitudes towards biodiversity.  相似文献   

15.
生态干扰度:一种评价植被天然性程度的方法   总被引:24,自引:1,他引:24  
地球上现存的植物或森林群落都是植被与其环境长期适应及人类长期干扰影响的结果 ,因此 ,现实的植被反映着历史上人类对它们不同程度的影响。‘生态干扰’的概念常常被用来描述历史上人类对植被或森林影响的大小 ,即‘生态干扰度’;或用来表示现实植被离开它的‘天然植被’的距离 ,即现实植被的‘天然性程度’。如此的‘天然植被’可以是 :( 1 )历史上从未受过人类任何干扰的‘原始植被’;( 2 )基于当前立地的‘潜在的自然植被’。然而 ,成百上千年以来人类对自然的利用干扰 ,致使真正的‘原始植被’现在几乎无处可寻。因此 ,‘潜在的自然植被’被用来作为生态干扰度估计或植被天然性程度评价的参照系。作为一种很实用的生态分析手段 ,生态干扰度的方法已被广泛地应用在农、林、水、景观、城市及自然保护等诸多领域的生态评价上。为此 ,本文论述了生态干扰度的概念、原理、方法和应用实例。  相似文献   

16.
《The Journal of geography》2012,111(9):541-544
Abstract

In the past decade, scientists have become increasingly concerned with man's pollution of the atmosphere and his inadvertent ability to effect change in climate at macro scales. The nature of such change is not yet known, but in this article, the premise that continued atmospheric pollution will promote higher air temperatures and ultimately coastal flooding through melting of all solid water forms, is accepted as inevitable. The author speculates on the probability of such an event and cartographically analyzes the possible extent of change in continental shapes and sizes, as well as the impact of world inundation on population densities and distributions. Projecting to 2050 A.D. as the earliest possible date for the maximization of this occurrence, it is expected that the expanding oceans will have reduced continental surfaces by approximately 17%, and roughly 19% of the population of the mid-21st century will have been relocated.  相似文献   

17.
Understanding the relative contributions of internal dynamics versus external factors in the process of community assembly is important for establishing guidelines for conservation and restoration of native vegetation. The role of internal dynamics and external factors in the process of community assembly at the local scale is a poorly understood issue in ecology, especially in highly variable environments. We analyse an 82-year spatiotemporal record of vegetation recovering from a history of overgrazing within a semi-arid environment to investigate the relative contribution of internal and external factors on community assembly. Community composition and spatial structure were used as indicators of change over time in four sites within a vegetation reserve, which were subjected to the same environmental constraints, climate and grazing history. The four sites follow remarkably different, asynchronous trajectories characterized by periods of stability interrupted by episodic change. The high variability between sites suggests that initial communities are internally reinforced through random chance events, directing them on different pathways of assembly and self-organization; hence external factors may play a less significant role in long-term community assembly at the local scale than previously believed. These results have important implications for rangeland restoration and conservation in many of the world's semi-arid regions.  相似文献   

18.
A palaeoecological investigation in the Bodø area (Salten, Nordland) records a shift from Betula-dominated forest to mostly treeless vegetation during the last 4000 years. Corylus avellana, now at its northern limits in this region, was previously more abundant within the area. Deforestation started c. 3500–3000 BP, most likely connected to human activity during the early Bronze Age. After the onset of anthropogenic disturbance, heathland was established, initially with a dominance of Calluna vulgaris and Empetrum. Later on, c. 900 BP, Calluna was dominant. The heathland was probably subject to management, including burning. It should be viewed as a part of a northern extension of the western European heathland vegetation of the coast of SW Norway.  相似文献   

19.
The need to improve the assessment of the wildfire hazard in nature reserves is considered. It is suggested that the natural vegetation fuel map compiled by using a specially developed determinant of the types of main conductors of burning having regard to the period of a fire-hazardous season should be used for such purposes. The types of prime conductors of burning constitute the major group of vegetation fuels which determines the possibility of the spread of burning across the territory covered by vegetation. A classification of this group was carried out on the basis of long-term pyrological investigations in different regions of the RF. The vegetation fuel maps are presented for the Stolby nature reserve, separately for the spring (autumn) and summer seasons, because the southern-taiga forests are characterized by a predominance of the grass forest types with the involvement of gramineous species. The map of the current wildfire hazard is compiled and presented as an example, on the basis of the vegetation fuel map for the spring (autumn) periods of the season for drought class II according to the weather conditions. This map is representative of the possibility or impossibility of the spread of burning for each area in the nature reserve in the event that the source of fire (of anthropogenic or natural origins) appears. It is shown that vegetation fuel map can be compiled for any nature reserve by using the determinant of the types of prime conductors of burning.  相似文献   

20.
Abstract

Einevoll, O. 1968. Land Classification Maps of Areas Basic to Agricultural Production. Norsk geogr. Tidsskr. 22, 264–270.

In Norway, a detailed land survey, based on photogrammetry, is now proceeding for land classification maps of the scale 1:5,000 (for certain minor areas 1:10,000) covering agricultural areas and including forest land. The areas to be mapped are classified according to land capability and general conditions of management. Containing a great deal of additional information as well, these maps will serve as a valuable aid in land use planning. The survey is designed to be completed in 12–15 year's time.

More roughly designed maps for the entire country on the scale 1:100,000 and 1:250,000, printed in colour, will be produced within two years' time. Intermediate maps of 1:20,000, containing an extended number of land types, will be undertaken gradually, after the appearance of the large scale map series. Property boundaries recorded in connexion with the surveying for the large scale maps will serve as the basis for a complete land register containing exact information about size and land properties of individual holdings.  相似文献   

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