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Habitat quality for many wildlife populations has a spatial component related to the arrangement of habitat elements across large geographic areas. With remote sensing and GIS technology, this paper presents an approach to calculate Habitat Suitability Index (HSI) for Giant Pandas to evaluate the habitat quality. In this paper, a buffer of a given distance (30 km or more) to the Giant Panda distribution area estimated in three national surveys (1974, 1989 and 2002), which is located in Sichuan, Gansu and Shanxi provinces in western China, was used as the study area. In order to study different species group’s habitat quality, the study area is divided into five parts: the Qinling mountain systems, located in the southeast in Shanxi province, the Minshan mountain systems, located in the south in Gansu province and northwest in Sichuan province, the Qionglai mountain systems, the Xiangling mountain systems and the Liangshan mountain systems, located in the west of Sichuan province, conforming to the five big Giant Panda species groups. Three physical environmental factors (elevation, slope and aspect), one ecological factor (vegetation distribution) and several human-influence factors (distances to highways, general roads, inhabitants and rural areas) are selected as the influence factors to calculate HSI. Each factor was reclassified by grid-cell (30 × 30 m per cell) to the suitability index scale from 0 to 1 based on habitat affinities before final calculation. After analyzing the HSI values on the most Giant Panda distribution area, 0.0144 was considered as the threshold habitat quality. Then, HSI was calculated for five mountain systems for three periods conforming to three national surveys (1974, 1989 and 2002). Several benefits to the approach can be highlighted. Firstly, HSI can be used as the standard to evaluate the quality of Giant Panda habitat. Secondly, by using HSI maps from 1974, 1989 and 2002, we can see that the Giant Panda habitat was the largest in 1974, and was then reduced much before 1989. However, by 2002, it had recovered to some extent, which conforms to the habitat data from the three national surveys. Thirdly, the habitat changes in the five mountain systems examined in the study are different. Finally, nature reserves play an important role in the protection of Giant Panda habitat; there are more suitable habitats in nature reserves than non-protected areas.
The project "Italian Map of Nature" (IMN) is dedicated to create an electronic map (GIS) of the environmental state (quality and vulnerability) of the Italian territory at different scales. Up to now the GIS of IMN is offering maps at a scale 1:50,000. The environmental quality is estimated on the basis of biological description of habitats that can be mapped at this scale, the vulnerability on the basis of variables related to the anthropogenic pressure. In this paper I want to show that the information collected for creating the data base of habitats for mapping purposes may be useful for getting information related to the climatic niche width of the species considered habitat indicators. In this paper I consider the heath species characterizing the IMN habitats of Italy in order to get an indirect estimation of the climatic vulnerability of Italian heathlands. To measure the climatic niche width of the species I propose a formula that combines the number of habitats (they characterize) with the heterogeneity of the habitats according to their distribution in altitudinal belts and in biogeographic regions. The results offer parameters on which to base a discussion for policy conservation of heaths and heathlands in Italy under the perspective of climate change.
The relief of the Zadroże Dune was described, as well as the comparison was done on its vegetation cover and the flora in its two phases of the development, i.e. before the afforestation of the dune and approximately 60 years after reconstruction of the forest. The first state was described in the paper dated 1949. During that period the dune constituted the first common study area for the research team consisting of ecologists and geographers from the Nicolaus Copernicus University. Our contemporary scientific studies were carried out in 2009. In the comparative analysis, a particular attention was paid to the distribution, the number and the size of heath patches with Arctostaphylos uva-ursi. In the description of the contemporary state of vegetation, the structure and the biomass of tree stands were included. The GIS and GPS technologies were applied in the comparative analysis of the vegetation, in the comparison of the former and contemporary cartographic materials, aerial and satellite images, as well as in the development of a digital elevation model. As a result of comparisons of the vegetation cover, it was found that the surface area of heaths decreased from 59.21 ares in 1948 to 2.96 ares in 2009. As a result of comparisons of the flora, it was found that 7 and 26 species of lichens occurred in 1948 and 2009 respectively, 5 and 42 species of mosses, 0 and 7 species of liverworts, as well as 102 and 204 species of vascular plants. The number of families, within which the species of vascular plants are classified, increased from 31 to 52. The compared floras have only 66 species in common. The percentage contribution of geographical and historical groups has undergone only inconsiderable changes during the 60-year period. Contribution proportions of non-synanthropic spontaneophytes and apophytes has changed slightly. Whereas, the contribution of alien species, mainly kenophytes and ergasiophytes significantly increased. This paper discuss the significance of natural and anthropogenic factors, which brought about this considerable range of transformations in the species composition and in the contribution of alien species.
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