Soil respiration and temperature sensitivity characteristics of forest and grassland in urban green space in Changsha City
Urban green spaces play a significant role in mitigating urban carbon emissions and the greenhouse effects.Soil respiration is a crucial aspect of the carbon cycle in urban green spaces,determining the effectiveness of the ecosystem's carbon sequestration function.Taking the forest and grassland ecosystems in Broad Town in Changsha City,Hunan Province as the research objects,the soil respiration rates and soil environmental conditions were monitored from November 2021 to December 2022.Combined with the extreme drought event in 2022,the soil respiration characteristics of forests and grassland ecosystems were analyzed,as well as their responses to extreme drought.The results showed that the soil respiration rates of forest and grassland ecosystems in summer and autumn(231.98 and 239.33 mg·m-2·h-1,respectively)were higher than those in winter and spring(179.28 and 91.15 mg·m-2·h-1,respectively)(calculated as C).Soil respiration changed significantly under extreme drought,and was more pronounced in forest ecosystems.At an annual scale,the soil carbon emissions of forest and grassland ecosystems were 681.55 and 564.66 g·m-2·a-1(calculated as C),respectively.The temperature sensitivity coefficient(Q10 values)of soil respiration in forest and grassland ecosystems ranged from 0.81 to 1.06 and from 1.19 to 1.80,respectively.The grassland ecosystem was more sensitive to temperature changes,which might lead to more soil carbon loss under extreme drought conditions.The research can provide a scientific basis for urban green space development and the realization of urban"carbon neutrality".
urban green spacessoil respirationtemperature sensitivityextreme droughtChangsha City
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万方数据
