Characteristics of Soil Respiration and Its Influence Factors in Oasis-Desert Transitional Belt of Shule River Basin
Soil respiration is one of critical problems to study of carbon cycle in terrestrial ecosystem. The influence factors (vegetation coverage, soil temperature, air humidity, soil moisture, soil salt, pH, HCO3-, Cl-, Ca2+, Mg2+, SO42-, K+, Na+) and its change characteristics of soil respiration during the different seasons (May, July and October) in oasis-desert transitional belt in Yumen County of Gansu Province are studied by the methods of geostatistics at 500 m sampling scale. Relationships between soil respiration rate and influence factors were analyzed. Results showed that soil respiration in desert was 1.21μmol·m-2·s-1, in oasis was 4.85μmol·m-2·s-1, it was rising four times in oasis than in desert. From the point of view of seasonal variation, soil respiration was the highest in July and the lowest in October, the middle of in May, it belonged to medium variability (10%≤CV≤100%) and coefficient variation (CV) was 64.1%~78.1%, the nugget was 0.065 and 0.113 in July and October, respectively, both of them were less than 0.25, a strong spatial correlation is seen between soil respiration in desert and oasis, moreover, spatial correlation was median and the nugget was 0.690 in May. It was found that there was a significantly positively correlation between soil respiration and soil temperature (P=0.002).
Shule river basinoasis-desert transitional beltsoil respirationseasonal variationinfluence factors
国家科技期刊平台
NSTL
万方数据
维普
