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1.
The process of habitat degradation varies in habitat type and driving force which shows certain spatial and temporal heterogeneity on regional scales. In the present study, a new diagnostic model for enclosed bay habitat degradation was established, with which the spatial and temporal variation patterns of habitat degradation during 1991–2012 in Sansha Bay, Fujian, China was investigated. The results show that anthropogenic disturbance is the major controlling factor for the habitat degradation in large temporal heterogeneity in the bay. On the other hand, the habitat degradation experienced signifi cant spatial variations among six sub-bays. Under the joint action of temporal and spatial heterogeneity, the degradation trend in growing scale shows a more signifi cant correlation with the distribution of local leading industries along shorelines. Therefore, we quantifi ed the main characters of habitat degradation in Sansha Bay, and have understood the relationship between the status of habitats spatio-temporal variation value and the main controlling factor leading to the changes. However, a defi ciency of this research is the lack of or inaccessible to the detailed data, which shall be better solved in the future study for accessing more data from more sources.  相似文献   

2.
Unbalanced inputs and outputs of material are the root cause of habitat degradation in Sansha Bay,Fujian Province,China. However,the cumulative pollution varies in different geographic locations and natural conditions in the enclosed bay. In this study,hydrodynamic conditions,sediment characteristics,and aquaculture methods were recognized as the underlying causes of spatial heterogeneity in the distribution of nitrogen and phosphorous pollutants,the two major controlling factors of habitat degradation in the bay area. In order to achieve the goal of balancing nutrient inputs and outputs in Sansha Bay,we developed a feasible and practical zone restoration strategy for reasonable adjustment and arrangement of aquaculture species and production scale in accordance with varying hydrodynamic conditions and sediment characteristics in six sub-bay areas(sub-systems). The proposed zone restoration strategy lays a solid foundation for habitat restoration and management in Sansha Bay.  相似文献   

3.
Combination of ecoprofile and least-cost model for eco-network planning   总被引:1,自引:0,他引:1  
The protecting requirements and functional connectivity of species in isolated habitat patches are crucial factors of eco-network planning.This study aimed to improve the method of eco-network planning for species conservation.Ecoprofiling was used to group the species by similar behavior types,namely,choice of ecosystem,area requirement,and short distance dispersal abilities.A least-cost model was used to simulate the optimal corridor location to maintain functional connectivity.A combination of ecoprofile and least-cost model was hired to develop an eco-network that promoted species conservation.A case study was also conducted in Bei-jing,China.In addition to the required ecosystem,habitat area is an important parameter for habitat extraction.Habitat area can remove noise habitat patches because of lacking area.Short-distance dispersal can be used to identify corridor requirements and avoid unneces-sary building requirements.Species with various dispersal abilities exhibit significant differences in terms of corridor length and loca-tion requirement.Habitat isolation is the main threat for weakly mobile species,and habitat loss is the major risk of mobile species pro-tection.Different species groups also exhibit distinct landscape pattern demands for an eco-network,and the eco-network planning based on specific species can not protect other species.We proposed that a combination of ecoprofile and least-cost model improved the efficiency of species conservation by eco-network planning.  相似文献   

4.
Mountain ecosystems are relatively more vulnerable to climate change since human induced climate change is projected to be higher at high altitudes and latitudes. Climate change induced effects related to glacial response and water hazards have been documented in the Himalayas in recent years, yet studies regarding species’ response to climate change are largely lacking from the mountains and Himalayas of Nepal. Changes in distribution and latitudinal/altitudinal range shift, which are primary adaptive responses to climate change in many species, are largely unknown due to unavailability of adequate data from the past. In this study, we explored the elevational distribution of butterflies in Langtang Village Development Committee (VDC) of Langtang National park; a park located in the high altitudes of Nepal. We found a decreasing species richness pattern along the elevational gradient considered here. Interestingly, elevation did not appear to have a significant effect on the altitudinal distribution of butterflies at family level. Also, distribution of butterflies in the area was independent of habitat type, at family level. Besides, we employed indicator group analysis (at family level) and noticed that butterfly families Papilionidae, Riodinidae, and Nymphalidae are significantly associated to high, medium and low elevational zone making them indicator butterfly family for those elevational zones, respectively. We expect that this study could serve as a baseline information for future studies regarding climate change effects and range shifts and provide avenues for further exploration of butterflies in the high altitudes of Nepal.  相似文献   

5.
In this study, the simulating waves nearshore(SWAN) model with a locally refined curvilinear grid system was constructed to simulate waves in Jervis Bay and the neighbouring ocean of Australia, with the aim of examining the wave characteristics in an area with special topography and practical importance.This model was verified by field observations from buoys and acoustic Doppler profilers(ADPs). The model precisions were validated for both wind-generated waves and open-ocean swells. We present an approach with which to convert ADP-observed current data from near the bottom into the significant wave height. Our approach is deduced from the Fourier transform technique and the linear wave theory. The results illustrate that the location of the bay entrance is important because it allows the swells in the dominant direction to propagate into the bay despite the narrowness of the bay entrance. The wave period T p is also strongly related to the wave direction in the semi-enclosed bay. The T p is great enough along the entire propagating direction from the bay entrance to the top of the bay, and the largest T p appears along the north-west coast,which is the end tip of the swells' propagation.  相似文献   

6.
基于蚁群算法的城市可持续发展综合评价   总被引:1,自引:0,他引:1  
在可持续发展体系分类的基础上,应用蚁群算法对可持续发展各分类指数公式和综合指数公式进行优化,建立可持续发展评价模型。将该模型应用于乌鲁木齐市可持续发展水平评价,评价结果与现状分析一敛。结果表明该模型简单适用、有良好的通用性。  相似文献   

7.
A Lagrangian tracer model is set up for Hangzhou Bay based on Coupled Hydrodynamical Ecological model for Regional Shelf Sea (COHERENS). The study area is divided into eight subdomains to identify the dominant physical processes, and the studied periods are March (the dry season) and July (the wet season). The model performance has been first verified by sea-surface elevation and tidal current observations at several stations. Eight tracer experiments are designed and Lagrangian particle tracking is simulated to examine the impact of physical processes (tide, wind and river runoff) on the transport of passive tracer released within the surface layer. Numerical simulations and analysis indicate that: (1) wind does not change the tracer distribution after 30 days except for those released from the south area of the bay during the wet season; (2) the tide and the Qiantang River runoff are important for particle transport in the head area of the bay; (3) the Changjiang River runoff affects the tracer transport at the mouth of the bay, and its impact is smaller in the dry season than in the wet season. Supported by the Natural Science Foundation of China (No.40576080); National High Technology Research and Development Program of China (863 Program, No. 2007AA12Z182)  相似文献   

8.
Arjinshan National Nature Reserve (ANNR) is one of 3 refuges of the endemic ungulates Tibetan wild ass (Equus kiang), Chiru (Pantholops hodgsonii) and wild yak (Bos mutus) that are endangered by natural and anthropogenic factors in the Qinghai-Tibetan Plateau (QTP). Identifying habitat suitability is critical for species protection management. We used a GIS-based niche model to delimit and classify habitat suitability using an integrated assessment system, which included 9 biotic and abiotic factors. We divided the research area into 4 habitat types for these ungulates: (1) high suitability habitat; (2) moderate suitability habitat; (3) low suitability habitat; and (4) unsuitable area. Results suggested that chiru have the most areas of high and moderate suitability habitats while Tibetan wild ass had the largest areas of low suitability habitat and unsuitable area. Wild yak had the largest area of moderate and low suitability habitat, but high suitability habitats for wild yak were smaller than those of other 2 ungulates. There was overlap of high-quality habitat for the three kinds of ungulates in the vicinity of Kardun inspection station, which could be regarded as the core area for the coexistence and conservation of these endangered ungulate populations.  相似文献   

9.
Based on Landsat TM images, we explored the pattern of variation of suitable waterbird habitats from 1990 to 2008 in the Dongtan area of Chongming Island at the Changjiang (Yangtze) River mouth. By applying our highly accurate indicator model (R=0.999, P<0.01), we quantified the variations of fluctuation intensity for local waterbird habitats during 1990-2008, and for the main waterbird groups (Anatidae, Charadriidae, Ardeidae and Laridae) from 2006 to 2008, to evaluate the impact of habitat quantity change on the waterbird habitat status and the population dynamics of the different waterbird groups. The results show that the aquaculture ponds (AP) and the Scirpus mariqueter zone (SMZ) underwent drastic habitat changes during certain periods (AP: 1997-2000, 2000-2003, 2005-2008; SMZ: 1997-2000), and the fluctuation intensity differed among habitat types in the order AP>SMZ>TSH (total suitable habitat)>BSA (bare mud flat and shallow water area). The abandonment of tracts of aquaculture ponds in Dongtan in mid-2006 brought about an intensive population fluctuation, caused by rapidly changing habitat with the population expanding to adjacent areas. At present, Anatidae and Ardeidae are threatened in the Dongtan area with declining populations because of their very "picky" habitat requirements (i.e., high reliance on AP). The Charadriidae experienced enormous population declines in the late 1990s, however, they have since recovered to normal levels as habitat change has stabilized. Our findings suggest that the current challenges for habitat management are the protection and stabilization of AP and SMZ habitats.  相似文献   

10.
We present a GIS-based habitat suitability index(HSI) model to identify suitable areas for Zostera marina L. restoration in the subtidal zone of Xiaoheishan Island. The controlling factors in the model,in order of importance,are Secchi depth,sediment composition,water temperature,salinity,current velocity,water depth and nutrient quality. Specific factor piecewise functions have been used to transform parameter values into normalized quality indexes. The weight of each factor was defined using expert knowledge and the analytic hierarchy process(AHP) method. All of the data thus obtained were interpolated using the inverse distance weighted(IDW) interpolation method to create maps for the entire region. In this study,the analysis of habitat suitability in the subtidal zone of Xiaoheishan Island was conducted for four seasons. According to the GIS-based HSI model,the optimal habitat of Z ostera marina L. appears in spring,although habitat remains suitable all year round. On the whole,the optimum site for eelgrass restoration is located in the eastern region,followed by the western and southern regions. We believe that the GIS-based HSI model could be a promising tool to select sites for Z ostera marina L. restoration and could also be applicable in other types of habitat evaluation.  相似文献   

11.
Similar to other areas of Pakistan, land resources in Khyber Pakhtunkhwa (KP) is kept under various ownership regimes for socio-economic and ecological benefits. For the last three to four decades, communal lands and resources are subjected to high rate of degradation and deterioration, which is leading to multifarious socio-economical and ecological implications. This paper intends to look into factors that are responsible for the degradation of communal land and the adaptability of the management mechanisms developed by the local inhabitants to conserve these resources. Moreover, this study also explores the sustainability of these adopted strategies in present circumstances. Data regarding socio-economic parameters of the inhabitants and their interactions with communal lands were collected through questionnaire cum interview method. As long-term climatic data for the area do not exist therefore focus group discussions were conducted to document the changing trend in rainfall regimes and temperature variations for the last about four decades. Results indicate that communal lands are highly vulnerable to degradation due to biophysical and anthropogenic factors. Local inhabitants have developed suitable measures to control the situation, however, accelerated socio-economic transformations in the area have weakened the role of local institutions and that led to further degradation of these resources. Nevertheless, a number of locally formulated rules have been revived and implemented and it is hoped that these threatened resources would be conserved.  相似文献   

12.
金钟山国家级自然保护区黑颈长尾雉生境适宜性评价   总被引:1,自引:0,他引:1  
为加强对珍稀动物黑颈长尾雉(Syrmaticus humiae)的保护,本研究以广西金钟山国家级自然保护区的黑颈长尾雉野外实地调查数据为基础,在地理信息系统(GIS)技术支持下,以植被类型、植被覆盖度、海拔和坡度为评价因子,采用生境适宜性评价模型,对黑颈长尾雉潜在生境的适宜性进行了评价。研究结果表明:(1) 黑颈长尾雉最适宜的生境是海拔1000~1850 m、坡度为5~25 o、盖度大于70%的落叶阔叶林,这些区域应该成为重点保护的生境;(2) 保护区内黑颈长尾雉分布的生境类型有25种,鉴于保护的有效性和成本,选择面积占主导的15种生境类型为潜在生境,其中,54.31%的潜在生境分布在核心区内,15.75%分布在缓冲区,29.94%分布在实验区;(3) 生境适宜性评价结果表明,保护区适宜栖息生境的面积达74 km2,约占保护区总面积的36.30%。最后,基于黑颈长尾雉在金钟山自然保护区的生境适宜性研究范围提出了相应的保护对策。  相似文献   

13.
基于地理探测器的大熊猫生境适宜度评价模型及验证   总被引:4,自引:0,他引:4  
动物生境适宜度评价对于野生动物生境保护十分重要。基于物种活动点来建模的生态位模型是目前应用最广泛的动物生境评价方法,但该方法不能直接表达生境适宜度与环境因子间具有生态学意义的数量关系。本文以雅安地区为例,提出一种新的大熊猫(Ailuropoda melanoleuca)生境适宜度评价方法,选取海拔、坡度、坡向、地形指数、距水源距离、植被类型、主食竹及距公路距离8个环境因子,引入地理探测器,在分别基于MAXENT模型和层次分析法(The Analytic Hierarchy Process,AHP)所构建生境适宜度模型的基础上,通过4个地理探测器(风险探测器、因子探测器、生态探测器和交互作用探测器)探寻大熊猫生境与各环境因子间的关系以及环境因子对大熊猫生境的影响机理,并将其预测结果与单一MAXENT模型和AHP法进行对比。结果表明:(1)AHP、AHP-Geogdetector、MAXENT和MAXENT-Geogdetector模型总体评价精度分别为85.6%、86.5%、91.3%和94.2%,kappa系数分别为0.699、0.718、0.821和0.882,AUC值分别为0.902、0.928、0.949和0.966,模型所预测的适宜和较适宜区与实际分布区重叠比分别为63.66%、61.30%、76.70%和90.10%,说明AHP-Geogdetector和MAXENT-Geogdetector模型精度均比相应的单一模型有所提高,且MAXENT-Geogdetector模型精度最高;(2)基于地理探测器的大熊猫生境适宜度评价模型能以“生境适宜度和环境因子间具有生态学意义的数量关系”的形式直接体现环境因子对动物生境利用的生态学作用,具有较好的生态学可解释性。因此,用地理探测器进行大熊猫生境适宜度评价具有较好的可行性。  相似文献   

14.
We present a GIS-based habitat suitability index (HSI) model to identify suitable areas for Zostera marina L. restoration in the subtidal zone of Xiaoheishan Island. The controlling factors in the model, in order of importance, are Secchi depth, sediment composition, water temperature, salinity, current velocity, water depth and nutrient quality. Specific factor piecewise functions have been used to transform parameter values into normalized quality indexes. The weight of each factor was defined using expert knowledge and the analytic hierarchy process (AHP) method. All of the data thus obtained were interpolated using the inverse distance weighted (IDW) interpolation method to create maps for the entire region. In this study, the analysis of habitat suitability in the subtidal zone of Xiaoheishan Island was conducted for four seasons. According to the GIS-based HSI model, the optimal habitat of Zostera marina L. appears in spring, although habitat remains suitable all year round. On the whole, the optimum site for eelgrass restoration is located in the eastern region, followed by the western and southern regions. We believe that the GIS-based HSI model could be a promising tool to select sites for Zostera marina L. restoration and could also be applicable in other types of habitat evaluation.  相似文献   

15.
1IN TR O D U C TIO NEcologicaldem onstration area (ED A )isan authoritativenom ination by N ational Environm ental Protection A d-m inistration ofC hina,w hich firstbegan itsexperim entalconstruction ofED A in 1995 and w asprom ulgated "N a-tionalExam ina…  相似文献   

16.
村镇应急公共设施选址布局优化研究   总被引:1,自引:0,他引:1  
应急公共设施对防灾减灾具有重要作用,但相关研究和实践通常围绕城市展开,中国村镇地域广阔、环境复杂,传统方法规划的应急公共设施布局无法满足村镇的需求。因此,针对村镇进行更加精细化的应急公共设施布局优化十分必要。本文主要研究内容包括:① 建立包括地理因素、交通条件、人口分布情况和危险源分布情况在内的应急设施适宜性用地指标体系,并避免在地质灾害、洪水等灾害高发区域建设;② 对仅需要承担应急服务的设施,建立集合覆盖模型和最大化覆盖模型两级选址模型进行分析,对需要承担公共服务和应急服务双重任务的设施,建立集合覆盖模型和p-中值模型进行分析;③ 以响应覆盖率、交叉响应率作为效率性评价指标,最大响应时间、平均响应时间作为公平性评价指标,综合评价设施选址方案。本文以神农架林区松柏镇为研究区域,以消防设施和应急医疗救助中心分别作为两类典型应急公共设施进行布局,得到以下结论:① 应急设施适宜性用地评价指标体系能够综合评价应急设施选址时需要考虑的各种因素,具有较强的实用性;② 对多选址方案进行对比,模型计算结果在效率性和公平性指标方面优于原选址方案,同时结合人口分布、实际用地情况和成本因素能够确定更为优化的布局方案,验证了方法的可行性和科学性。  相似文献   

17.
Sustainable development is the theme of the 21st century. To monitor the progress of sustainable development, the United Nations launched Sustainable Development Goals(SDGs) in 2015. Subsequently, nations of the world have drawn up a list of localized indicators regarding the United Nations SDGs as a paradigm. We established a database including SDGs indicator systems of 11 economies by collecting and determining a large number of materials. Based on this database, we analyzed SDGs indicators by...  相似文献   

18.
在深入分析区域水资源可持续利用评价系统的基础上,建立了区域水资源可持续利用能力评价指标体系,并将基于禁忌搜索优化的投影寻踪技术(TSPP)应用于水资源可持续利用评价。通过对淮河片区水资源可持续利用能力的初步研究,表明了此模型能完整而系统地反映区域水资源可持续利用能力,并且直观、简便,在各种实际系统评价中具有应用价值。  相似文献   

19.
Finding the right balance between timber production and the management of forest-dependent wildlife species, present a difficult challenge for forest resource managers and policy makers in Okinawa,Japan. A possible explanation of this can be found in the unique nature of the forest management area which is populated with various kinds of rare and endangered species. This issue has been brought to light as a result of the nomination of northern Okinawa Island in 2018 as a candidate for World Natural Heritage site. The nomination has raised public awareness to the possibility of conflicting management objectives between timber extraction and the conservation of habitat for forest-dependent wildlife species. Managing exclusively for one objective over the other may fail to meet the demand for both forest products and wildlife habitat,ultimately jeopardizing the stability of human and wildlife communities. It is therefore important to achieve a better balance between the objective of timber production and conservation of wildlife habitat.Despite the significance of this subject area, current ongoing discussions on how to effectively manage for forest resources, often lack scientific basis to make sound judgement or evaluate tradeoffs between conflicting objectives. Quantifying the effect of these forest management activities on wildlife habitat provides useful and important information needed to make forest management and policy decisions. In this study we develop a spatial timber harvest scheduling model that incorporates habitat suitability index(HSI)models for the Okinawa Rail(Gallirallus okinawae),an endangered avian species found on Okinawa,Japan. To illustrate how the proposed coupling model assembles spatial information, which ultimately aids the study of forest management effects on wildlife habitat, we apply these models to a forest area in Okinawa and conduct a simple simulation analysis.  相似文献   

20.
为分析高黎贡山羚牛生境质量状况,探讨其生境保护策略。本文建立高黎贡山自然保护区北段范围的数字地形模型,并将其应用在濒危珍稀动物--羚牛的生境评价研究中。通过羚牛活动区的海拔高度、坡度及植被类型等数据的叠置分析,获得了羚牛的潜在生境区,同时再综合考虑人类活动对其影响,便得到羚牛的实际生境。结合羚牛的生态习性与实地调查资料,选择海拔高度、坡度、植被因子、人类活动影响因子四个指标对其生境的适宜性进行了划分和评价。结果表明:(1)无人类活动影响下,羚牛可在研究区内大部分地区生存。从1974、1989、1999、2004年几个时相的图像分析,适宜羚牛生存的生境面积逐年减少,而不适宜的面积逐年增加。(2)人类活动影响下,适宜羚牛生存的生境大面积消失,生境丧失比例逐年增加。  相似文献   

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