Soil respiration(RS)is an important carbon budget in urban ecosystem.In order to better understand the limiting factors affecting urban soil respiration,we measured RS,soil temperature,soil moisture content,soil organ...Soil respiration(RS)is an important carbon budget in urban ecosystem.In order to better understand the limiting factors affecting urban soil respiration,we measured RS,soil temperature,soil moisture content,soil organic carbon(SOC),nitrogen(N),C/N,dissolved organic carbon(DOC),microbial biomass carbon(MBC),NO_(3)^(-)-N,NH4þ-N,P and fine root biomass from twelve sites of four green-land types(campus green-land,park green-land,residential green-land and factory green-land)for two years in built-up areas of Hefei,China.The results showed that average annual RS was significantly lower in the residential green-land(1.35μmol m^(-2) s^(-1))than in the campus(2.64μmol m^(-2) s^(-1))and park(2.51μmol m^(-2) s^(-1))green-lands.RS positively increased with soil temperature at the range of 2.01–31.26℃,and Q_(10) values ranged from 1.48 to 1.65 in the four types of green-lands.Soil moisture(18–25%)showed significantly positive correlation with soil respiration(P<0.01).When precipitation occurred frequently in wet summer,soil moisture served as the dominant control on R_(S) variations.R_(S) was positively related with SOC,NO_(3)^(-)-N,P and fine root biomass(diameter <2 mm),while negatively correlated with DOC at 0–10 cm depth.Our results indicate that decreasing R_(S) may be an optional way to increase carbon sequestration potential for urban ecosystem,and this can be achieved by regulating green-land types and applying appropriate soil nutrients maintenance practices.展开更多
基金This research was supported by the National Natural Science Foundation of China(31370626)and Anhui Provincial Natural Science Foundation,China(1408085QC69).We are grateful to Lingmei Zeng,Lei Wang,Yang Zhao,Jiajia Zhou,Hao Chen and Weibin Yin for field work,and Mengxin Zhang for laboratory assistance.We also would like to thank the reviewers and editors for constructive comments and suggestions.
文摘Soil respiration(RS)is an important carbon budget in urban ecosystem.In order to better understand the limiting factors affecting urban soil respiration,we measured RS,soil temperature,soil moisture content,soil organic carbon(SOC),nitrogen(N),C/N,dissolved organic carbon(DOC),microbial biomass carbon(MBC),NO_(3)^(-)-N,NH4þ-N,P and fine root biomass from twelve sites of four green-land types(campus green-land,park green-land,residential green-land and factory green-land)for two years in built-up areas of Hefei,China.The results showed that average annual RS was significantly lower in the residential green-land(1.35μmol m^(-2) s^(-1))than in the campus(2.64μmol m^(-2) s^(-1))and park(2.51μmol m^(-2) s^(-1))green-lands.RS positively increased with soil temperature at the range of 2.01–31.26℃,and Q_(10) values ranged from 1.48 to 1.65 in the four types of green-lands.Soil moisture(18–25%)showed significantly positive correlation with soil respiration(P<0.01).When precipitation occurred frequently in wet summer,soil moisture served as the dominant control on R_(S) variations.R_(S) was positively related with SOC,NO_(3)^(-)-N,P and fine root biomass(diameter <2 mm),while negatively correlated with DOC at 0–10 cm depth.Our results indicate that decreasing R_(S) may be an optional way to increase carbon sequestration potential for urban ecosystem,and this can be achieved by regulating green-land types and applying appropriate soil nutrients maintenance practices.
