森林凋落物-土壤动物-土壤系统中营养元素含量关系及分异

根据对吉林省左家自然保护区同一坡面上不同地形部位的凋落物、土壤动物及土壤中N、P、K、Ca、Mg、Fe 6种营养元素含量实测数据,研究了凋落物、土壤动物体内和土壤中的营养元素差异以及坡面上营养元素的纵向分异。结果表明,在较缓的丘陵坡面上,6种营养元素的纵向分异并不十分显著。土壤动物体内N、P、Ca含量明显高于凋落物和土壤,土壤中K、Mg、Fe元素含量则高于土壤动物和凋落物。坡面中部凋落物、土壤动物及土壤中N元素含量高于坡面两端,土壤中的P、K元素含量在坡体上部出现最大值,Mg、P元素纵向分布呈线性分布规律,Ca元素分布波动幅度较大,且呈非线性规律。凋落物、土壤动物和土壤中元素含量线性关系较强。凋落物和土壤动物体内元素的变异对土壤中元素含量变化的贡献率较大。

The relation and difference of nutritional elements in forest litter-macrofaunas-soil system

There are many reports about the characteristics of spatial distribution of chemical elements in different soils and the interactions between macrofaunas and litter or soil,especially,about the horizontal distribution.However,researches on the vertical distribution are limited.And there are few researches into the relationships among forest littermacrofaunas-soil.This paper tends to combine them into the whole and studies the nutritional elements through forest litter,macro faunas and soil.The study area is a shady slope on a low hill located in the Zuojia Natural Reserve(126°～126°2′E,44°03′～44°04′N) in Jilin province.The mean altitude is 300m.The region belongs to the temperate continental monsoon climate.The zonal soil is dark brown soil.The vegetation is mainly secondary mixed deciduous broadleaf forests with Quercus mongolica and Tilia mandshurica as the dominant species.Four sampling sites are located on the same slope surface but different habtats,such as the valley,foot hill,the middle section and the peak.Forests litter,macrofaunas and soil samples were sampled in each habitat,every 20 apart along the slope.The contents of nutritional elements N,P,K,Ca,Mg,and Fe of litter-macrofaunas-soil were measured in laboratory.The relation and difference of nutritional elements in litter-macrofaunas-soil and the vertical difference in nutritional elements of the same slope surface were studied.The result indicated that the vertical difference of six elements was not quite remarkable on the hill slope surface.The contents of N,P and Ca in macrofaunas were higher than those of litter and soil,but the contents of K,Mg and Fe in soil were more than those of macrofaunas and litter.The changes of N in litter,macrofaunas and soil are consentaneous,that is the content of N in the middle position of the slope surface was higher than in the valley and the peak.This is consistent with the surface soil organic matter.On the upper part of the slope,the contents of P and K were the maximum.The vertical variational trend of Mg and P was level,but the content of Ca fluctuated within a great range.The linear relation of the element content in litter-macrofaunas-soil was better.The variations of elements in litter and macrofaunas contributed to the variations of elements in soil to a greater extent.The variations of N,P,K,Ca and Fe in litter influenced more on the soil than on the macrofaunas.