淮北平原四种土地利用类型非生长季土壤呼吸速率

Soil respiration flux of four land-use types in non-growing season in North Plain of Huai River

为了探讨杨树人工林撂荒地、农耕地、农林复合模式的林地和农林复合小麦地的4种土地利用方式对温室气体CO2增长及其通量的影响,利用Licor-8100土壤碳通量测定系统对以上4种不同土地利用的土壤呼吸速率变化进行了研究。结果表明:4种土地利用类型的土壤呼吸速率在非生长季冬季的月内变化和日变化不明显,都保持在低的CO2释放水平;不同土地利用类型土壤呼吸速率表现出明显的空间异质性;农林复合小麦地土壤呼吸速率在非生长季与其影响因素的关系在2009年12月份的关系不明显,2010年1月份和2月份随着气温的升高,土壤呼吸速率与温度的相关性逐渐增大,与其他因子的相关性也变大,但增加的幅度较小;4种土地利用类型中,农林复合冬小麦地的CO2平均通量为最小,CO2的释放量比例最小,为22.55%,比农田小麦地、撂荒地和农林复合隔离带林地分别减少3.02%、0.85%和6.00%的CO2释放。农林复合模式的CO2释放量比农田小麦地多释放2.85%,与人工林撂荒地的土壤呼吸速率相同。

To probe the effects of four land-use types, i.e. wood land and wheat land of agro-forestry model, poplar plantation abandoned land and wheat land, on the increase and the flux of CO2,the licor-8100 Automated Soil CO2 Flux System was used to monitor the change of carbon flux of soil from the four land-use types. The soil respiration （Rs） of them was studied systematically. The results showed that the monthly variation and diurnal variation of Rs of four land-use types were lower and had no significant change. The average soil respiration flux of wheat land of agro-forestry model was the smallest and the contribution rate of respiration flux of soil was 22.55%, which was 3.02% less than that of crop land, 6.00% less than that of wood land of agro-forestry model and 0.85% less than that of the plantation abandoned land. The soil respiration flux of agro-forestry model was 2.85% less than that of the plantation abandoned land and was the same with that of wheat land. The relationship of soil respiration and the factors was not significant in October, but became significant with temperature inereasing and other factors in January and February.