科尔沁沙地不同环境条件下植物叶凋落物CO2释放研究  

Study on CO_2 Release of Leaf Litters in Different Environment Conditions in the Horqin Sandy Land

作　　者：孟庆涛[1] 李玉霖[1] 赵学勇[1] 赵玉萍[1] 罗亚勇[1] 

机构地区：[1]中国科学院寒区旱区环境与工程研究所

出　　处：《干旱区研究》2008年第4期519-524,共6页Arid Zone Research

基　　金：中国科学院寒区旱区环境与工程研究所(O65044400);国家自然科学基金(40601008);中国科学院野外台站基金项目(1731690200015)

摘　　要：采用可以有效控制环境因子的室内土壤培养试验，对不同生境土壤、土壤水分及温度作用下叶凋落物释放CO2的情况进行了初步研究。结果表明：①在培养的前4d，土壤水分含量越高，叶凋落物释放CO2的速率越快；而从整个培养期来看，沙地中较低的含水量对叶凋落物释放CO2的速率无显著的影响。②在流动沙地和半流动沙地的生境中，凋落物释放CO2的总量高于丘间低地和固定沙地。③叶凋落物释放CO2速率与环境温度呈显著的正相关（F=0.7316，P〈0．01）。在10℃，20℃以及30℃条件下，CO2的释放速率均较为平稳，而在40℃时0～16d呈现出明显逐步加快的趋势，在17～24d则缓缓下降并趋于平稳。Litter decomposition is one of the important factors affecting carbon circle of ecosystems. On the one hand, litter decomposition can generate soil nutrient, on the other hand, litters can catch rainfall, store some rainwater against permeation into ground, reduce evaporation from ground surface and increase soil moisture content. Litters can also affect the carbon balance of terrestrial ecosystems. In this study, a laboratory soil incubation experiment with controllable environment factors is carried out, and the effects of leaf litters on CO2 release in different sandy habitats and under different soil moisture content and temperature conditions in Horqin Sandy Land are researched. The results are as follows： （ 1 ） In first four days, the higher the soil moisture content was, the faster the CO2 release rate of leaf litters would be ; but the effect of low soil moisture content on CO2 release rate of leaf litters in sandy land was not so significant in the whole experiment; （2） The quantity of CO2 release of leaf litters is higher in mobile and semi-mobile dunes than that in fixed dunes and inter-dune lowlands; （3） There is a significant positive correlation between the CO2 release rate of leaf litters and the temperature （F =0. 738 6, P 〈0. 01 ） ; CO2 release rate of leaf litters is relatively stable under temperatures of 10℃, 20 ℃ and 30℃, it is gradually increased under temperature of 40℃ during the experimental period of 0～16 days, but it is slowly decreased during the experimental period of 17～24 days.

关 键 词：科尔沁沙地 枯枝落叶 土壤含水量 沙漠化 温度 CO2释放 

分 类 号：S154[农业科学—土壤学]