摘要
土壤在全球碳平衡中具有举足轻重的作用,而土地利用变化对土壤碳排放的影响也是极其敏感的。针对贵州岩溶峡谷地区石漠化导致的土地退化对土壤碳排放的影响进行研究。试验定位监测样地选取在石漠化典型地区——贵州省关岭布依族苗族自治县花江峡谷区,于2012年7月至2013年4月采用动态气室法(Li-8100,USA)监测了未石漠化土地和不同程度石漠化土地的土壤呼吸速率日动态和季节动态变化,通过关岭布依族苗族自治县治理前后石漠化程度监测数据分析,定量评价了石漠化对区域土壤碳排放量的影响,可为定量评价石漠化对土壤碳汇功能的影响提供科学依据。研究结果表明:1)岩溶区土壤呼吸速率与土地的石漠化程度具有很高的关联性,石漠化程度越高,土壤碳排放量越低,极重度石漠化土地样地土壤碳排放量约为非石漠化的1/2;2)非石漠化土地土壤呼吸具有明显的季节变化,而石漠化土地土壤呼吸则不再遵循植物生长的季节顺序发生变化,土壤呼吸随季节的这种变化规律被打破;3)区域碳排放变化量与石漠化治理效果有关,2005—2010年关岭布依族苗族自治县实施石漠化治理后,区域土壤呼吸产生的碳排放量增加了41 800 t,相当于关岭布依族苗族自治县岩溶区增加了31.92t/km2。
Soil plays an important role in the global carbon balance, while soil carbon is sensitive to the change of land use. The paper addresses the scientific question that how will the land degradation and the decreasing of the quality of soil influence the soil carbon emissions, which was caused by the rocky desertification. We selected monitoring plots in the typical rocky desertification area of Huajiang Karst Gorge in Guanling County of Guizhou Province. We used the Li-8100 automated soil CO2 flux system to monitor the daily and seasonal variations of soil respiration from 2012 to 2013 in the fields via the monitored data analysis of the area and degrees of rocky desertification land of Guanling County before and after the rocky desertification management. The influence of rocky desertification management on soil carbon emissions was evaluated quantitatively. The research aimed to provide scientific basis for assessment of the influence of rocky desertification on soil carbon emissions. The research suggested that ： 1） Soil respiration rate in rocky region had a very high concordance with the degree of rocky desertification, the higher the degree of rock desertification was, the lower the amount of soil respiration was, and the amount of soil carbon emissions of seriously significant rocky desertification land was half of that of non-rocky desertification land; 2） Soil respiration rate of non-rocky desertification land had obvious seasonal variations, while the soil respiration rate of rocky desertification land did not follow the rule of plant growth as the season went by, and the rule of soil respiration rate＇ s seasonal variation was broken ; 3 ） The regional soil carbon emissions was connected with the governance of rocky desertification, and that of Guanling County produced by soil respiration increased by 41 800 t when the rocky desertification management was implemented from 2005 to 2010, which was equal to 31.92 t/km2 C increased in the karst region of this county.
出处
《北京林业大学学报》
CAS
CSCD
北大核心
2014年第1期26-33,共8页
Journal of Beijing Forestry University
基金
国家林业局科技项目"岩溶石漠化治理效益监测与评估技术研究"
