土地利用类型对千烟洲森林土壤碳矿化及其温度敏感性的影响

应用生态学报

土地利用类型对千烟洲森林土壤碳矿化及其温度敏感性的影响

李杰^1,2,魏学红¹,柴华¹,王若梦²,王丹²,何念鹏^2**

(¹西藏大学农牧学院, 西藏林芝 860000; ²中国科学院地理科学与资源研究所生态系统网络观测与模拟重点实验室, 北京 100101)

出版日期:2014-07-18 发布日期:2014-07-18

Impacts of land-use types on soil C mineralization and temperature sensitivity of forests in Qianyanzhou, Jiangxi Province, China.

LI Jie^1,2, WEI Xue-hong¹, CHAI Hua¹, WANG Ruo-meng², WANG Dan², HE Nian-peng^2

(¹College of Agriculture and Animal Husbandry, Tibet University, Linzhi 860000, Tibet, China; ²Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China)

Online:2014-07-18 Published:2014-07-18

摘要/Abstract

摘要：

土壤有机质分解是陆地生态系统碳循环的重要环节，它不仅受温度和水分的影响，还对土地利用变化十分敏感.以中国科学院千烟洲生态试验站的柑橘园和湿地松人工林为对象，研究不同土地利用类型、温度(5、10、15、20和25 ℃)和水分(30%、60%和90%饱和含水量)对土壤碳矿化及其温度敏感性的影响.结果表明：土地利用类型、温度和水分对土壤碳矿化都具有显著影响，且各因素间存在显著的交互效应.柑橘园和湿地松人工林土壤碳矿化速率均与温度呈正相关，60%饱和含水量处理下土壤碳矿化速率最高.在相同的温度和水分处理下，柑橘园土壤碳矿化量显著高于湿地松林.土地利用类型和水分对土壤碳矿化温度敏感性(Q₁₀)具有显著影响.培养7和42 d，土壤碳矿化的温度敏感性随水分升高而上升；柑橘园温度敏感性高于湿地松林，且水分越高差异越明显.包含温度和水分的双因素模型可以很好地模拟土壤碳矿化对温度和水分的响应，温度和水分共同解释土壤碳矿化变异的79.9%～91.9%.

Abstract: Decomposition of soil organic matter plays an important role in the regulation of carbon (C) cycles at ecosystem or regional scales, and is closely related to temperature, moisture, and landuse types. The influences of soil temperature, moisture, and landuse types on soil C mineralization in Citrus reticulata and Pinus elliottii forests were investigated at the Qianyanzhou Ecological Experiment Station, Chinese Academy of Sciences, by conducting incubation experiments at 5-level temperatures (5, 10, 15, 20 and 25 ℃) and 3-level moistures (30%, 60% and 90% saturated soil moisture, SSM). The results showed that soil temperature, moisture, and land-use types had significant effects on soil C mineralization and they had significant interaction effects. Soil C mineralization was positively correlated with incubation temperature in the two forests, and the maximum of soil C mineralization was in the 60% SSM treatment. The accumulation of soil C mineralization was higher in the C. reticulata forest than in the P. elliottii forest under the same temperature and moisture conditions. The temperature sensitivity (Q₁₀) of soil C mineralization was influenced by landuse type and soil moisture. Q₁₀ increased with the increasing soil moisture in both C. reticulata and P. elliottii forests at incubation 7 and 42 d. Q₁₀ in the C. reticulata forest was higher than in the P. elliottii forest in the same moisture level, and the deviation increased with the increasing soil moisture. The model including temperature and moisture could depict the response of soil C mineralization to temperature and moisture. Temperature and moisture together explained 79.9%-91.9% of the variation in soil C mineralization.

李杰1,2,魏学红1,柴华1,王若梦2,王丹2,何念鹏2**. 土地利用类型对千烟洲森林土壤碳矿化及其温度敏感性的影响[J]. 应用生态学报.

LI Jie1,2, WEI Xue-hong1, CHAI Hua1, WANG Ruo-meng2, WANG Dan2, HE Nian-peng2. Impacts of land-use types on soil C mineralization and temperature sensitivity of forests in Qianyanzhou, Jiangxi Province, China.[J]. Chinese Journal of Applied Ecology.