秭归县防护林健康评价指标体系的建立及应用

以秭归县防护林为研究对象,通过传统生态学调查和相关室内分析,在林分水平上建立了包括林分结构、林分功能、生态环境和健康风险4个一级指标、20个二级指标的防护林健康评价指标体系。在综合相关林分健康评价的基础上,制定防护林健康评价指标优劣等级表,采用Delphi-AHP法设置指标权重,利用生态系统健康综合指数模型计算防护林健康指数,分析秭归县防护林健康状况。结果表明:秭归县防护林健康综合指数的范围在0.5000—0.9000之间,健康指数均值为0.6921,秭归县防护林整体处于亚健康状态;9种防护林类型健康状况排序为:阔叶混交林针阔混交林针叶混交林阔叶纯林马尾松纯林柏木纯林其它针叶纯林经济林灌木林,即是混交林纯林经济林灌木林;秭归县防护林健康指数具有空间变异性,在水平方向上,秭归县辖下乡、镇防护林健康指数从南向北有逐渐递减的趋势,在垂直方向上,防护林健康指数随海拔增高逐渐增大,海拔1000 m以上逐渐降低,健康指数表现出随海拔升高由小变大、又由大变小的变化特点。

Health evaluation model of shelterbelt and its application in Zigui County of the Three Gorges Reservoir area

Based on the traditional forest field surveys and related analysis, twenty indexes in four aspects of forest stand structure, forest stand functional, ecological environment, and health risks were selected to represent the shelterbelt forest health status. As a result, the health evaluation model of shelterbelt was developed. Additionally, the weights and levels of different aspects and factors were then determined according to the Delphi-AHP model and its ecological significances. To illustrate the health evaluation model, the health status of shelterbelt in Zigui Country was evaluated. The evaluation results showed that the health index of shelterbelt in Zigui Country varied at the range from 0.5000 to 0.9000. Its mean value was 0.6921. The results indicated that the shelterbelt in Zigui Country were in the sub-health state. But, the health status is different in the nine types of forests. The health rank is broad-leaved mixed forest > coniferous and broad-leaved mixed forest > coniferous forest > broad-leaved forest > masson pine forest > cedar forest > other coniferous forest > economic forest > shrubbery. It revealed that the health ranks of forest vegetation types varied along the order of the mixed forest > pure forest> economic forest > shrubbery. Additionally, a significantly spatial heterogeneity was founded in the health status of shelterbelt in Zigui Country. The health index of shelterbelt varied along with a decreasing trend from south to north in Zigui Country. The shelterbelt in the southern area had better health status. A single peak trend in topography was also founded in the health status of shelterbelt in Zigui Country. The health index of shelterbelt increased below 1000m while decreased above 1000m.