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1.
The role of corridors in mitigating the effects of landscape fragmentation on biodiversity is controversial. Recent studies have highlighted the need for new approaches in corridor design using long-term datasets. We present a method to identify transit corridors for elephant at a population scale over a large area and an extended period of time using long-term aerial surveys. We investigated environmental and anthropogenic factors directly and indirectly related to the wet versus dry season distribution of elephant and its transit corridors. Four environmental variables predicted the presence of elephant at the landscape scale in both seasons: distance from permanent water, protected areas and settlements and vegetation structure. Path analysis revealed that altitude and monthly average NDVI, and distance from temporary water had a significant indirect effect on elephant distribution at local scale in dry and wet seasons respectively. Five transit corridors connecting Tarangire National Park and the northern as well as south-eastern wet season dispersal areas were identified and matched the wildlife migration routes described in the 1960s. The corridors are stable over the decades, providing landscape connectivity for elephant. Our approach yielded insights how advanced spatial analysis can be integrated with biological data available from long-term datasets to identify actual transit corridors and predictors of species distribution.  相似文献   

2.
Fragmentation leads to the loss of connectivity among forested landscapes, which is important for biological conservation and biodiversity maintenance. Fragmentation analysis carried out on 20 years time interval in northern-Western Ghats revealed that, losses under moderate and high fragmented forests have decreased from 1985–87 to 2005; however, it is not enough to compensate the loss of intact forests (not fragmented). The area of dense forests in intact forests has decreased from 1985–87 to 2005, this essentially means the loss of quality habitat in the area. While investigating connectivity between fragmented patches by taking different topographical and ecological parameters into the consideration, it was observed that potential connectivity exists between protected areas present in northern and southern areas.  相似文献   

3.
Zusammenfassung Der Verfasser bringt zun?chst die verschiedenen Formeln, die für einfache Koordinatentransformationen, d. h. zur Umrechnung von zwei unver?nderlich miteinander verbundenen Punkten ohne Wechsel des Referenzellipsoides, angewendet werden, in Erinnerung und empfiehlt dann die Formeln (4) und (5) mit den Verbesserungsausdrücken (9), wobei die Bezeichnungenr, s, t, q durch die Gleichungen (6) und (8) definiert sind. Diese Formeln sind trotz ihrer Einfachheit genauer als diejenigen vonHelmert undHristow, denn füre=0 stellen sie die genauen sph?rischen Formeln (2) und (3) dar. Die Verformung der geschlossenen Polygone, entsprechend den ?nderungen der Krümmung des Ellipsoids, ist schon fühlbar durch die Glieder mite 2α2 und macht eine erh?hte formelle Genauigkeit trügerisch.
Resumen Después de recordar las diferentes fórmulas aplicadas para las transformaciones sencillas de las coordenadas, es decir, para el desplazamiento de puntos invariablemente ligados, sin cambiar el elipsoide de referencia, el autor recomienda las fórmulas. (4) y (5) con los términos correctivos (9), en que las cantidaderr, s, t, q, están definidas por las ecuaciones (6) y (8). Estas fórmulas, a pesar de su sencillez, son más precisas que las deHelmert yHristow, porque parae=0 son las fórmulas esféricas exactas (2) y (3). Las deformaciones de los poligonos cerrados, debidas a las variaciones de curvatura del elipsoide, es ya sensible por los términos en e2 σ2 y hace, en consecuencia, illusoria una precisión superior

Résumé Après avoir rappelé les différentes formules appliquées pour les transformations simples des coordonnées, c'est-à-dire pour le déplacement de points invariablement liés, sans changer l'ellipso?de de référence, l'auteur recommande les formules (4) et (5) avec les termes correctifs (9), dont les termesr, s, t, q sont définis par les équations (6) et (8). Ces formules, malgré leur simplicité, sont plus précises que celles d'Helmert etHristow, car poure=0 ce sont les formules sphériques exactes (2) et (3). La déformation des polygones fermés, due aux variations de courbure de l'ellipso?de, est déjà sensible par les termes en e2 σ2, et rend en conséquence illusoire une précision formelle supérieure.

Sommario Dopo richiamate le varie formule fin qui proposte per la trasformazione delle coordinate sull'ellissoide in un moto rigido sulla superficie dello stesso, l'autore raccomanda le formule (4) et (5) con i termini correttivi (9), i cui coefficientir, s, t, q, sono definiti dalle equazioni (6) ed (8). Queste formule, malgrado la loro semplicità, sono più precise di quelle diHelmert e diHristov, in quanto pere=0 esse forniscono le formule sferiche esatte (2) e (3). La deformazione dei poligoni chiusi, dovute alle variazioni nella curvatura dell'ellisoide, si rende già sensibile nei termini in e2 σ2, e rende illusoria una maggiore precisione formale.
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4.
近年来,我国公路对自然生态环境的影响随着通车里程的增加而日益显著。在公路选线的过程中,全面分析拟建公路走廊带内景观破碎度的空间分异特征,可有效减少公路修建对生态环境的不利影响。本文利用遥感分类技术和GIS(地理信息系统)空间分析方法,以湖南长湘公路走廊带某段土地斑块和景观分类为基础,借助斑块密度指数、最大斑块指数和相似邻近比指数,在斑块类型水平和景观水平两个层面全面分析公路走廊带内自然林地景观、农业景观和城乡建设景观破碎度的空间分异特征。结果表明:长湘公路走廊带内景观破碎度高的地区主要分布在大型斑块边缘、平原地区以及公路沿线;自然林地景观和农业景观的破碎度较低,城乡建设景观的破碎度较高;城乡建设景观的破碎度与公路相关性最强,表现出顺应公路走向的条带状蔓延特征。该研究成果可为公路选线方案的制订和完善提供环境影响方面的参考。  相似文献   

5.
Zusammenfassung Die Ideen und Anregungen, die der Ingenieur-Geograph Dr. MichelDupuy, Paris, hinsichtlich der vielseitigen Verwendungsm?glichkeiten von Korrelatentabellen (Tafeln der Kehrmatrizen von Winkelnormalgleichungs-Systemen) in der geod?tischen Praxis an dieser Stelle ver?ffenllicht hat, werden ebenso lebhaft begrü?t wie seine Vorschl?ge zur weiteren Verfolgung des vonBoltz, Friedrich, Marcantoni und dem Verfasser eingeschlagenen Weges. Stellungnahme zu den Anregungen im einzelnen. Vorschlag eines Gedankenauslausches zwischen den interessierten Fachleulen verschiedener Nationalit?t.
The ideas of Mr. Dupuy about the use and future arrangement of tables of correlatives
Summary The author deals with the ideas of Dr. MichelDupuy (Paris), concerning the future arrangement of tables of correlatives (tables of inverse matrices of angle equation systems) and their use in practical theoretical work published in this periodical. Following the author, the proposals of Dr.Dupuy, referred in detail, are of high value and exchange of ideas between interested specialists of different nationality seems to be worth of consideration.

Resumen El autor discute las ideas de Mr.Dupuy (Paris) relativas a la confección de las tablas de correlativas (matrices inversas de las matrices de las ecuaciones de ángulos) y a su uso desde el punto de vista práctico y teórico. Según el autor, las propuestas de Mr.Dupuy son muy importantes y los cambios de ideas entre especialistas de los diferentes paises merecerian ser examinadas.

Sommario L'A. discute le idee del Sig.Dupuy (Parigi) relative alla costruzione di tavole di correlativi (matrici inverse delle matrici delle equazioni agli angoli) ed il loro uso dal punto di vista pratico e teoretico. Secondo l'A. le considerazioni del Sig.Dupuy sono importantissime e gli scambi d'idee tra specialisti di differenti Paesi meritano incoraggiamento.
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6.
Protected areas are established to conserve unique features and biodiversity of the nature. Accordingly, wherever has one of the natural, ecological and/or cultural values it should be considered a protected area. Kave-Deh No-hunting Area is located on extremely east of Tehran Province in an area of 94,961 ha. Due to rich and diverse land cover, distinctive wildlife species, and unique monuments the area was selected as a case study to examine the possibility of its promotion to the protected area using Spatial Multi Criteria Evaluation (SMCE) Method. For this purpose, the relevant criteria were identified by Delphi method. After finalization of the most important criteria by Delphi panelists, the map layers were prepared at the scale of 1:100000, in the environment of GIS Software. Afterwards, the map layers were divided into factors and constraints of which factors were standardized by S-shaped membership functions of fuzzy logic. The dimensionless factor maps were weighted using Analytical Hierarchy Process (AHP) Method in the environment of Expert Choice Software. Subsequently, a mathematical equation was extracted to conduct the land suitability analysis. The Weighted Linear Combination (WLC) Method was applied to overlay the map layers and obtain the final ‘nature conservation’ land use map. The final land suitability map showed that 34,687 ha of whole study area (equal to 37 %) have the potentiality for promotion to the protected area.  相似文献   

7.
在汶川-芦山两次强震作用下,先天脆弱与高风险并存的山区县成为受灾最为严重的地理单元。针对灾区地理信息离散度高、可变参数多、收集难度大等现状,选取雅安芦山"4·20"地震重灾区宝兴县为实证研究区,应用3S技术,基于信息数据库逻辑设计原理,构建了震后统一投影坐标系统的地理信息数据库。在此基础上,结合实例介绍了数据库的应用:叠加分析、专题图可视化。灾区宝兴县震后地理信息的数字化和集成化,通过数据库支撑下的GIS空间分析功能和可视化表达,可为灾区重建规划选址和灾害风险评价提供数据支撑。  相似文献   

8.
Protected areas are experiencing increased levels of human pressure. To enable appropriate conservation action, it is critical to map and monitor changes in the type and extent of land cover/use and habitat classes, which can be related to human pressures over time. Satellite Earth observation (EO) data and techniques offer the opportunity to detect such changes. Yet association with field information and expert interpretation by ecologists is required to interpret, qualify and link these changes to human pressure. There is thus an urgent need to harmonize the technical background of experts in the field of EO data analysis with the terminology of ecologists, protected area management authorities and policy makers in order to provide meaningful, context-specific value-added EO products. This paper builds on the DPSIR framework, providing a terminology to relate the concepts of state, pressures, and drivers with the application of EO analysis. The type of pressure can be inferred through the detection of changes in state (i.e. changes in land cover and/or habitat type and/or condition). Four broad categories of changes in state are identified, i.e. land cover/habitat conversion, land cover/habitat modification, habitat fragmentation and changes in landscape connectivity, and changes in plant community structure. These categories of change in state can be mapped through EO analyses, with the goal of using expert judgement to relate changes in state to causal direct anthropogenic pressures. Drawing on expert knowledge, a set of protected areas located in diverse socio-ecological contexts and subject to a variety of pressures are analysed to (a) link the four categories of changes in state of land cover/habitats to the drivers (anthropogenic pressure), as relevant to specific target land cover and habitat classes; (b) identify (for pressure mapping) the most appropriate spatial and temporal EO data sources as well as interpretations from ecologists and field data useful in connection with EO data analysis. We provide detailed examples for two protected areas, demonstrating the use of EO data for detection of land cover/habitat change, coupled with expert interpretation to relate such change to specific anthropogenic pressures. We conclude with a discussion of the limitations and feasibility of using EO data and techniques to identify anthropogenic pressures, suggesting additional research efforts required in this direction.  相似文献   

9.
以单镜头四旋翼小型无人机为试验设备,针对复杂山地地区单一、高落差滑坡体,本文提出采用面向滑坡体立面航线规划,结合传统单水平航线、井字形交叉航线规划,构建不同航线下的三维模型。通过重叠度、三维模型完整性、布设地面标靶分析三维模型精度3个方面,对不同航线下构建三维模型的方法进行评价分析。试验结果表明,采用立面航线能达到98.72%航向重叠度和88.82%旁向重叠度;采用立面航线得到的模型纹理细节、颜色信息和地面信息的丰富程度均优于传统两者航线所得到的;通过地面标靶的测量误差计算,采用立面航线得到的模型精度更高。  相似文献   

10.
ABSTRACT

Photo-sharing services provide a rich resource of crowdsourced spatial data consisting of georeferenced imagery and metadata. Shared photos can provide valuable information for a variety of applications and geospatial analysis tasks, such as identifying tourist hot spots or traveled routes. Understanding the spatiotemporal patterns of photo contributions will allow analysts to assess the suitability of these data for related analysis tasks. Using California as a study area, this paper analyzes various aspects of photo contribution patterns of Panoramio and Flickr. It identifies areas where annual photo contributions are still growing and areas that undergo a decline in annual contributions. Multiple regression is used to identify which environmental correlates are associated with an increase in photo-sharing activities. Furthermore, panel data of annual contributions between 2006 and 2013 for California subcounties will be used in a regression model to demonstrate that there is a positive feedback effect between Panoramio and Flickr photo contributions, but no neighborhood effect. The results of this paper provide insight into the data quality of crowdsourced image collections. These collections are commonly used for geospatial applications, including tourist information services and the computation of scenic routes.  相似文献   

11.
在人群密集的大型楼宇,构建基于楼宇内部空间三维拓扑结构的逃生疏散路径,是当前路径规划算法研究的难点和热点。本文对当前常见的路径规划算法进行优劣对照比较,并详细阐述其在楼宇内部逃生疏散场景应用的算法思想和主要特征,最后总结了楼宇内部路径规划算法研究的发展方向。  相似文献   

12.
India has a rich repository of flora and fauna, but the rapid decline of wildlife and threat to its habitat has been a serious cause of concern. Hence, protected areas have been set up to achieve specific conservation objectives to facilitate timely and reliable information on forest types and its composition, degradation status and their suitability for different species of flora and fauna. In the present study, evaluation of tiger habitat in Corbett Tiger reserve is carried out using remote sensing, ground and other ancillary sources and is integrated using GIS using multi-criteria model. The results indicated that sal, mixed sal, miscellaneous forest, plantation, grassland, agriculture and scrub land are the major land use/land cover types and majority of the study area is covered under dense forest. Tiger habitat suitability analysis showed that large proportion of the area (51.4%) was found to be highly suitable followed by moderately suitable area (31%). Further, the correlation drawn between range-wise suitability area and actual tiger population in Corbett Tiger Reserve CTR indicated a positive correlation of 0.73. Disturbance to wildlife habitat, vegetation degradation and shrinking passage corridor are the major concern in CTR.  相似文献   

13.
In this study, remote sensing (RS) with computer-based geographic information systems (GIS) techniques are used as a tool for monitoring the water basin area and water quality in Istanbul's relatively less polluted and comparatively less destroyed catchment of the metropolis drinking water dam reservoir named Terkos. It is necessary to work with recent data to be able to identify the effects of urbanization on the water quality of the Terkos dam catchment area that supplies drinking water to the metropolis. RS is an important tool to monitor water quality and urban terrain. For this aim, a project has been initiated at the Technical University Remote Sensing Laboratory, under the Istanbul Water and Sewerage Administration (ISKI) sponsorship in Istanbul. The project uses SPOT-PAN, XS and IRS-1C/D PAN and satellite data of 1993 and 2000 for urban analysis and Landsat-TM and LISS-III satellite data of 1992 and 2000 for water quality. For calibration and validation, ground truth samples are collected from the experimental area. The RS data was converted into the UTM coordinate system and image enhancement and classification techniques are used. Raster data is converted to vector data to assess the study area for analyzing in GIS for the purpose of planning and decision-making on protected water basin zones. As a result of monitoring land use and water quality changes, recommendations are made for planning and management of the protected environment of the Terkos catchment protected area. Measuring land use change is a very important issue for controlling the future development of the basin, GIS techniques are performed and results are illustrated in established models on the four protected zones of Terkos water basin.  相似文献   

14.
Hong Kong as an international metropolis is well known for its vibrant urban life, which attracts millions of mass conventional tourists for shopping and business. Recently, ecotourism has flourished and attracts ecotourists who visit the ecological and cultural resources of the rural landscape, country parks and marine parks. Yan Chau Tong, also known as ‘Double Haven’, is remote from the urban centre, which helps preserve its natural flavour and cultural heritages such as Hakka walled villages. It is noted as an important site for developing ecotourist activities. A symbiosis of humans and nature cannot be achieved without a sound planning and zoning scheme. This paper investigates the use of IKONOS imagery and a geographic information system for rational planning of ecotourist activities and conservation measures. Through image classification of IKONOS and integrated with ecological data, essential habitats can be mapped and a spatial database is established. Suitable sites for recreational activities (including camping, heritage visiting, hiking and snorkelling) and important ecological habitats can both be identified using multiple criteria evaluation techniques. The use of a multiple objective land allocation model helps resolve conflict between recreation and conservation. Sites are generally identified as (a) those where conservation or recreation should receive the highest priority; (b) those that can be treated as additional recreation or conservation sites; and (c) conflict areas that can serve both purposes. The result can assist in planning land resources for ecotourism to satisfy both objectives and attain sustainability in the area.  相似文献   

15.
Least cost path applications can be a powerful tool for understanding connectivity across a landscape. A limitation to this method is its difficulty in integrating terrestrial, marine, and cultural factors – all of which would have been at play in the prehistoric Aegean. This study looks at a method of modeling pathways that integrates major factors (land, sea, and culture) that would be in play while considering medium- to long-distance travel in the Aegean. This test case explores the possible relationships between proposed routes for communication and identified coastal sites with parameters modeled in geographic information system that affect travel in cultural, marine, and terrestrial contexts. The methods presented have significance beyond the Late Bronze Age Aegean. The development of a methodology that incorporates marine, cultural, and terrestrial environments provides a mechanism by which specific hypotheses regarding complex communication routes may be addressed in regions of the world where there is an intensive interplay between terrestrial and marine geographies.  相似文献   

16.
智能导游服务已从传统的单一景区导游发展为城市多景区导游,因此,包含了景区间导游和景区内导游两大部分;表现为更加注重面向散客服务、兼容多移动智能终端以应用程序(App)的方式运行。由于景区间导游和景区内导游往往自成系统,在游客进出景区的过程中存在着两种系统的切换,且主要采用手动方式完成,尚没有实现城市多景区导游过程的无缝衔接。为了应对这个挑战,本文设计了一个面向城市多景区的无缝导游服务模式,分析了其架构以及工作机制;并着重讨论了城市无缝导游服务的关键技术,如系统间无缝切换的条件,包含判断游客进入、离开景区等;以及导游服务过程无缝衔接的机制,包含导游动态数据结构的设计,游客游览需求、导游过程状态在多导游系统间的传递等。最后通过实例验证了该方法的有效性,作为新的导游服务模式,同时为动态集成已有的导游App提供了解决方法。  相似文献   

17.
The high biological diversity and rich genetic forest resources of the state of Sikkim are to be conserved due to their sensitiveness to environmental degradation through continued human interference. The conservation of bioprospecting zones in natural forests as well as in protected areas is considered important for up keeping genetic resources and their germplasm. Keeping this in view, ‘Fambong Lho’ wildlife sanctuary in East district, Sikkim, has been selected to characterize different communities in the dominant vegetation type of Tropical Broad Leaved Hill Forest and to assess biodiversity controls in respect of different topographical features, such as altitude, slope, and aspects and use these inputs for prioritizing the protected area into different Bioprospective zones for conservation and planning. An altitude above 2000 m, having a slope in the range of 1–5 percent facing south east aspect are the ideal environmental conditions conducive to have high species richness. The analysis of fragmentation indicates that the forests are under stress along the fringes as they are closely associated with the habitations. The biological richness is recorded reasonably within the limits in the core area of the park but further prioritizing of such areas for conservation is necessary in view of impending danger of frequent interaction of human habitation with in the sanctuary for forest resources.  相似文献   

18.
对两个有关土地利用状况调查区域的高光谱和Quickbird数据进行了数百次算法对比实验,最终确定Sym4和Db2是曲波变换中的最佳小波函数,提出两种基于曲波变换的高光谱遥感图像融合方法,即加权法和选择法,获得了更精确的高光谱遥感融合影像.在一个研究区域,通过对高光谱数据的子带分解、脊波变换、一定融合以及它们的逆变换等曲波变换过程,表明融合的高光谱遥感影像能提供许多有利于土地类型划分和影像识别的精确七地信息.在另一个研究区域,除进行曲波变换外,还通过二次多项式计算实现了高光谱与Quickbird数据遥感影像匹配,最终从高光谱与Quickbird数据获得的遥感融合影像经日视及信息熵、相关系数等评价表明,曲波变换融合图像优于小波变换融合图像,与Brovey融合图像相近,但比PCA融合图像稍差.客观和主观评价证实,曲波变换的遥感融合方法能为高光谱遥感图像在土地利用状况调查提供更多更准确的信息.  相似文献   

19.
为方便公众优化出行路径,规避或减少空气污染暴露损害,提出一种基于低空气污染暴露的健康出行路径动态搜索算法(dynamic healthy-route search algorithm,DHRSA),并设计开发了相应健康出行路线规划系统。该算法通过融合土地利用回归制图、暴露风险权重估算和Dijkstra最短路径搜索算法,基于实时空气污染情景动态规划健康出行路径。以长沙主城区为例进行随机车辆出行方式测试实验,通过比较DHRSA算法规划的健康出行路径与传统最短出行路径、最快出行路径的出行暴露风险,验证了该算法的可靠性与系统的实用价值。  相似文献   

20.
建筑物墙面、悬崖或危岩等目标物的立面信息对于地物精细化建模、地灾调查、分析、评估及防治等具有非常重要的作用。传统倾斜摄影测量获取影像的方式缺乏对地物立面信息的详细描述,在地形落差较大的地区也存在因影像重叠率不同而建模失败的情况。仿地飞行策略在一定程度上解决了上述问题,但其对于突然的高度变化,不能满足精细化建模的要求。本文提出了一种基于等高线构建无人机航线的新型仿地飞行策略,该方法基于目标区域的DSM生成等高线,经等高线简化、偏移等处理完成无人机航线的设计。通过试验将该方法构建的模型成果与传统仿地飞行方法建模成果相比较。结果表明,本文提出的方法可将悬崖上的危岩等刻画得更加真实,且相对于传统仿地飞行垂直于高度变化方向的航线设计为平行于等高线的航飞路线,避免了频繁的高度变化,有益于延长无人机执行飞行任务的时间,因此是一种有效、实用的航飞路线设计方法。  相似文献   

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