官山保护区白颈长尾雉栖息地适宜性评价

2009年4月-2009年5月和2009年12月-2010年1月,在江西官山国家级自然保护区对白颈长尾雉(Syrmaticus ellioti) 繁殖期和越冬期的栖息地进行调查。通过实地调查,结合已有研究结果,确定了官山自然保护区白颈长尾雉栖息地适宜性评价因子,即植被类型、海拔、坡度和坡向等4个栖息地因子。基于"被利用生境-可获得生境比较法",以对各评价因子不同梯度的资源选择指数为依据,确定了白颈长尾雉适宜性评价准则。应用ArcGIS 9.3空间分析功能和栖息地片断化指数,对官山保护区白颈长尾雉栖息地进行了适宜性评价。结果表明:在官山自然保护区适宜白颈长尾雉繁殖的栖息地斑块有502个,总面积为3307 hm²,占保护区总面积的28.6%,分离度指数和片断化程度指数分别为0.365和0.912;适宜白颈长尾雉越冬的栖息地斑块有514个,总面积2755 hm²,占保护区总面积的23.8%,分离度指数和片断化程度指数分别为0.443和0.939。官山保护区白颈长尾雉栖息地片断化较严重,片断化现象在白颈长尾雉越冬期加剧。因此,迫切需要采取措施白颈长尾雉现存栖息地进行保护,特别是要高度重视其越冬栖息地的保护。

Habitat suitability evaluation of Elliot's pheasant (Syrmaticus ellioti) in Guanshan Nature Reserve

Elliot's pheasant (Syrmaticus ellioti) is a threatened species of pheasants endemic to China, and habitat loss and fragmentation have become the main threats to its survival. The habitat suitability of Elliot's pheasant was evaluated in Guanshan National Nature Reserve (GNNR) in Jiangxi Province from April to May in 2009 and from Dec 2009 to Jan in 2010. We selected four habitat factors, i.e. vegetation types, altitude, slope degree and slope direction, for habitat suitability evaluation of this pheasant in GNNR according to the field survey during breeding season and wintering season and the existing results of the previous researches in relation to Elliot's pheasant. The habitat suitability evaluation criteria were determined based on the used-available habitat comparisons and the resource selection index of each habitat factor in different gradients. Moreover, we assessed the habitat suitability of Elliot's pheasant in GNNR using the spatial analysis of Arc GIS Version 9.3 and on the base of habitat fragmentation index. Elliot's Pheasant preferred the evergreen broadleaved forest (E_i=0.102), evergreen and deciduous broadleaved mixed forest (E_i=0.144) and coniferous-broadleaved mixed forest (E_i=0.138) in breeding season with an altitude of 400-700 meters (E_i= 0.385), a slope direction of 45-90°(E_i= 0.101), 90-135°(E_i= 0.124) and 135-180°(E_i=0.117), and a slope direction of 5-30°(E_i=0.264). There were 502 habitat patches in the suitable and sub-suitable habitat of this pheasant in breeding season with an area of 3307 hectare, accounting for 28.6% of the whole area of GNNR, and the splitting index and the fragmentation index were 0.365 and 0.912 correspondingly. The area of the suitable habitat of Elliot's pheasant in GNNR in breeding season was 1410 hectare with a splitting index of 0.659 and a fragmentation index of 0.958, while the area of the sub-suitable habitat was 1897 hectare with a splitting index of 0.545 and a fragmentation index of 0.942. In wintering season, the Elliot's pheasant in GNNR preferred the sites with an altitude of 300-600 meters (E_i= 0.245), a slope direction of as 90-135°(E_i= 0.205) and 135-180°(E_i=0.121) and a slope degree of 5-30°(E_i=0.295). At the same time, they mainly inhabited in the evergreen broadleaved forest (E_i=0.165), evergreen and deciduous broadleaved mixed forest (E_i=0.147) and coniferous-broadleaved mixed forest (E_i=0.129). The suitable and sub-suitable habitat of this pheasant in GNNR in wintering season occupied an area of 2755 hectare, responsible for 23.8% of the total area of this reserve, and included 514 habitat patches. The splitting index and the fragmentation index of these habitats were 0.443 and 0.939, respectively, and the areas of the suitable habitat and sub-suitable habitat in this season were 1162 hectare and 1593 hectare, respectively. The splitting indexes of the suitable habitat and sub-suitable habitat in wintering season were 0.721 and 0.639 correspondingly, and the fragmentation indexes of these two types of habitat were 0.996 and 0.982 respective. Our results suggested that habitat fragmentation of Elliot's pheasant in GNNR was at a serious situation, and it was much worse for that in wintering season. Therefore, it is reasonable to recommend that some measures should be taken to protect the existing habitat of the Elliot's pheasant, especially in the wintering season.