土壤呼吸在生态系统碳循环过程中占有重要地位，为探讨纳帕海流域生态系统土壤呼吸过程，于2014年8月中下旬期间，采用LI-8100开路式土壤碳通量测量系统对流域内7种植被类型土壤呼吸速率及其与土壤温度的响应规律进行了研究。结果表明：（1）各植被类型的土壤呼吸速率日变化都呈单峰曲线形式，最高值和最低值分别出现在13：00─16：00和2：00─8：00；（2）各植被类型土壤呼吸速率日均值为自然草地（5.506μmol·m-2·s-1）>轻度退化草地（4.322μmol·m-2·s-1）>高山灌丛（3.849μmol·m-2·s-1）>中度退化草地（3.226μmol·m-2·s-1）>重度退化草地（2.959μmol·m-2·s-1）>高山松Pinus densata林（2.260μmol·m-2·s-1）>青稞Hordeum vulgare Linn. var. nudum Hook.f.地（2.256μmol·m-2·s-1）；（3）当草地开垦为农田后，其土壤呼吸速率降为最低水平；（4）所有植被类型的土壤呼吸速率与5 cm土壤温度呈指数相关，其中在自然草地上，土壤温度对其土壤呼吸的影响最大，但温度敏感性却较低，重度退化草地的土壤温度对其土壤呼吸的影响最小，但温度敏感性最大。研究可见，区域内人类活动使草地退化、转变为农田等过程，导致其土壤呼吸速率显著下降。重度退化草地对温度变化所表现出的相对较高的敏感性，预示着在环境变化的影响下，生态系统过程及功能将会产生更大的波动。%Soil respiration plays an important part in the balance of the global carbon cycle of ecosystem, in order to study the process of soil respiration on Napa lake basin. By using LI-8100 automated soil CO2 flux system to determine soil respiration and soil temperature of seven different vegetation types on Napa lake basin during the mid-August of 2014. The results show:(1) daily variation curves of soil respiration rate were unimodal curves, the highest and the lowest soil respiration rate occurred at 13:00─16:00 and 2:00─8:00 respectively; (2) the mean soil respiration rate of different vegetation types were natural grassland (5.506μmol·m-2·s-1)>mild degraded grassland (4.322μmol·m-2·s-1)>alpine scrub (3.849μmol·m-2·s-1)>moderately degraded grassland (3.226 μmol·m-2·s-1) > severely degraded grassland (2.959 μmol·m-2·s-1) > alpine pine forest Pinus densata (2.260 μmol·m-2·s-1) >highland barley Hordeum vulgare Linn. var. nudum Hook.f. (2.256 μmol·m-2·s-1); (3) soil respiration decreased with increasing degradation degree at different degraded grassland, when assarted to cropland, its soil respiration rate was lowest; (4) there was a index variation between soil respiration and soil temperature at 5 cm depth. While soil temperature at 5cm depth carried a highest weight in the influence of soil respiration rate of natural grassland, but its temperature sensibility was lowest. When it comes to severely degraded grassland, soil temperature at 5 cm depth carried a lowest weight in the influence of soil respiration rate, but its temperature sensibility was highest. Research shows, human activities in the region make the grassland degradation and transform into farmland, resulting in a significant decrease in soil respiration rate. The relatively high sensitivity of severe degraded grassland to temperature changes indicates that the process and function of ecosystem will be more volatile under the influence of environmental changes.
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机译：samband mellan Undergrundens Jordart och Tillstand och dess Dynamiska E-modul（medelmodul）vid Olika arstider：En preliminaer Undersoekning（不同季节土壤中土壤类型和状况与土壤动态E-模量（平均模量）的关系）年份：初步调查）
