摘要
利用现地调查和试验林跟踪调查的方法,研究了黄土高原次生林和次生林改造后林地鼢鼠的发生规律。结果证明,次生林鼢鼠发生类型分为灌草群落类型、乔灌草疏林群落类型和乔木密林群落类型。次生林乔木郁被度与灌木分布数量是影响林地鼢鼠分布的主要因子。乔木和灌木的郁被度、沙棘和草本植被的权重、直根系草本植被的覆盖度等指标与林地鼢鼠密度呈负相关;而灌木权重、沙棘郁被度、直根系草本植被的权重、须根系草本植被的权重和覆盖度等指标与林地鼢鼠密度呈正相关。次生林改造后林地鼢鼠密度逐渐增大,达到最高以后随着林分郁被度的加大,鼢鼠密度逐渐降低。不同改造模式林地鼢鼠发生强度依次为全面清坡造林、坡向清坡带状造林、块状清坡造林、水平带状清坡造林和林下更新造林,油松林地大于侧柏林地,侧柏林地大于刺槐林地。
By using methods of fieldwork and test-woods research, on the loess plateau, this paper studied the occurrence regulation of zokor in secondary forests and improved secondary forests. The results showed that the zokor occurrence type could be divided into community types of shrub and grass, thin wood with arbor, shrub and grass and dense wood with arbor. The arbor shade density and the shrub proportion were main factors to influence zokor distribution in woodland. In the secondary forests, there was a negative relationship between the zokor density and the shade density of arbor and shrub, the proportion of Hippophae rhamnoides and herbage, the proportion and the cover degree of taproot herbage, a positive relationship between the zokor density and the shrub proportion, the shade density of H. rhamnoides, the proportion of taproot herbage, the proportion of fibre herbage, the cover degree of fibre herbage. In the improved secondary forests, the zokor density enlarged gradually, and decreased with the raise of shade density gradually. The zokor outbreak degree in different improved patterns was in order for over-all felling, vertical felling, patch felling and regeneration, meanwhile the zokor density in Pinus was higher than Platycladus orientalis, higher in Platycladus orientali than Robinia pseudoacacia.
出处
《西北林学院学报》
CSCD
北大核心
2007年第1期96-101,共6页
Journal of Northwest Forestry University
基金
国家科技攻关项目(2001BA509B07-2-02
2005BA529A05)
关键词
黄土高原
次生林改造
改造方式
鼢鼠
发生规律
loess plateau
improved secondary forest
improvement pattern
zokor
regularity of outbreak
