基于最小费用距离模型的自然保护区功能分区

合理的功能分区是维持自然保护区保护功能和实施有效管理的关键。功能分区的环套模式反映了生物保护的一种分级措施,而最小费用距离反映了物种的被保护程度和景观对物种的干扰程度等阻力特性,因此,功能分区阈值是联系这种阻力变化和分级保护措施的一个纽带。以老县城大熊猫自然保护区为例,提出了利用最小费用距离模型进行功能分区的方法。阻力层的确定、阻力值的赋予、功能分区阈值的确定等问题构成了应用最小费用距离模型进行功能分区的基本要素。研究结果表明:应用最小费用距离模型进行功能分区进一步丰富了功能分区的研究方法;最小费用距离应用于功能分区的关键点在于功能分区阈值的确定;利用标准方差分类方法可以设计不同安全水平的功能分区。

Research of the Nature Reserve Zonation Based on the Least-cost Distance Model

Reasonable zoning of the nature reserve is one of the key issues to maintain the na,ture reserve's ecological function and sustainable development.The zoning mode of the core,buffer,experimental zones reflects the grading measure of biological conservation.And the least,cost distance model describes the degrees of species conservation and of landscape disturbance on species.Thus the thresholds of zoning are the bridge of the least,cost distance and the functional zoning.In this paper,the feasibility of applying the least,cost distance model to nature reserve zoning was put forward.The methods and technologies of functional zoning by using the least,cost distance model based on classification of standard deviation were applied in the functional zoning of Laoxiancheng Nature Reserve.And the different safety modes of nature reserve zoning were constructed,which could promote the research of functional zoning. It was necessary to define the thresholds of the least,cost distance so that nature reserve zonation could be obtained automatically.The process of selective movement of species around environment was reflected by the model of the least,cost distance;therefore,the spatial variance of the least,cost distance could reflect the habitat's sudden change and stability.Based on the statistical concept,the paper classified the least,cost distance using the standard deviation,and obtained three thresholds of core,buffer and experimental zones. The procedure of zoning nature reserve based on the least,cost distance includes(1)to identify the sources;(2)to analyse the resistant layers;(3)to define resistant values;(4)to calculate the least,cost distance;(5)to setup three thresholds of nature reserve zoning;and(6)to implement the zonation.The main elements affecting the least,cost distance model were analysing the resistance layers,assigning the resistance values and defining the thresholds of zones. The results showed that(1)the selection of three thresholds of functional zoning was the key step of applying the least,cost distance model;(2)the different zoning models with various safety levels for buffer zones can be designed by utilizing the classification of standard deviation;(3) the calculation process of least,cost distance took many factors into account,such as elevation,slope,vegetation type,and the distribution of bamboo,which could further meet the demand of the designation of nature reserve;and(4)the proposed zoning approach for nature reserves based on the least,cost distance model was practicable and contributed a new content to the method system of nature reserves'functional zoning.Different safety,level zonations could regulate the management ability and further satisfy the real situation of nature reserve much more.This method could be applicated and extended to the related nature reserves which aimed at preserving endangered species.