中国生态农业学报2011，Vol.19Issue(4)：731-737,7.DOI:10.3724/SP.J.1011.2011.00731
温度和水分对黄土丘陵区3种典型土地利用方式下土壤释放CO2潜力的影响
Effects of temperature and moisture on soil CO2 release potential under three typical land use types in the hill-gully area of the Loess Plateau
摘要
Abstract
The most important greenhouse gases in the atmosphere are CO;, Criand N2O, which in total contribute approximately 80% to greenhouse effect. Soil respiration generally accounts for one half of total CO2 emission into the atmosphere, adding to greenhouse effect. In addition to other factors, soil respiration is highly related with temperature, moisture and soil type. However, few studies have investigated soil respiration under different land use types in the hill-gully area of the Loess Plateau. The objective of this experiment was to determine the effect of temperature, moisture and other related factors on soil respiration. For that purpose, undisturbed soil samples were collected from different land use types in the hill-gully area of the Loess Plateau. The study covered three land use types - 15-year old apple orchard land at Changwu, Shaanxi Province; 6-year old retrieving grass land at Guyuan, Ningxia Hui Autonomous Region; and 140-year old forest land at Fu County, Shaanxi Province. We used the S-distribution method to collect soil samples and the infrared absorption CO2 analyzer to measure soil respiration. CO2 release rate was analyzed in the laboratory using undisturbed soil samples under four temperatures of 5 °C, 15 °C,25 °C. And 35 °C;and five moisture contents of wilting water holding capacity, natural water holding capacity, fracture capillary water holding capacity, field capacity, and saturated water holding capacity. The aim was to determine the correct relationship among the factors and soil respiration rate. Factors that influenced soil CO2 release potential under different land use types in the Loess hilly-gully area were then determined. The results showed that under different land use types in the loess hilly region, the rates of soil respiration under different moisture contents were mainly driven by temperature variation. The "Ra=aehT" exponential model precisely forecasted the changes in respiration rate as affected by temperature. Though, soil moisture slightly influenced soil respiration rate, it greatly affected Q10, which indicated the sensitivity of soil respiration to temperature. Both high and low moisture contents inhibited the sensitivity of soil respiration. Whilethe rates of soil respiration substantially differed, it generally tracked the following order: forest land soil > grass land soil > orchard soil. Organic carbon significantly contributed to the variation in soil CO; release, followed by organic nitrogen. Furthermore, micro-bial biomass carbon might indirectly affect rate of soil respiration.关键词
土壤呼吸速率/温度/水分/黄土丘陵区/土地利用方式Key words
Rate of soil respiration/ Temperature/ Moisture/ Hilly-gully area of the Loess Plateau/ Land use type分类
农业科技引用本文复制引用
张宏,黄懿梅,祁金花,安韶山..温度和水分对黄土丘陵区3种典型土地利用方式下土壤释放CO2潜力的影响[J].中国生态农业学报,2011,19(4):731-737,7.基金项目
国家自然科学基金项目(40971171)、西北农林科技大学“青年学术骨干支持计划”和中国科学院“西部之光”人才支持计划项目资助 （40971171）
