title: Dynamic Changes of Soil Surface Organic Carbon under Different Mulching Practices in Citrus Orchards on Sloping Land.
abstract: Mulching management has been used in many places all over the world to improve agricultural sustainability. However, the cycling of carbon in the soil under applications of mulch on sloping arable land is not yet fully understood. A four-year field experiment was carried out in Xiaofuling watershed of Danjiangkou reservoir in China. The object was to evaluate the effects of the application of straw mulch (ST) and grass mulch (GT) on dynamic changes in soil organic carbon and its fractions. Results showed that mulch applied on the soil surface increased the contents of SOC and its active fractions in the soil. Compared to the control without cover (CK), ST and GT treatments increased the contents of SOC, LOC, DOC, POC and EOC by 14.73%, 16.5%, 22.5%, 41.5% and 21%, respectively, in the 0-40 cm soil layer, and by 17%, 14%, 19%, and 30%, respectively, in the 0-100 cm soil layer. The contents of organic carbon and its active fractions decreased with increasing soil depth in all of the treatments. SOC was accumulated in the period of December to the following March. The contents of soil DOC and LOC were high in January to March, while the contents of soil POC and EOC were high in June to September. The relative contents of soil organic carbon fractions were POC > EOC > LOC > DOC over the four years. Straw mulching had no significant effect on the changes in soil organic carbon active fractions during the different periods. Based on this long-term field experiment in Danjiangkou reservoir, we found that straw mulching had a significant effect on soil, increasing SOC content and stock in slopping arable land, and that live grass mulching was more effective than rice straw mulching. We discuss possible optimal periods for the implementation of mulching practices on sloping land.
authors.affiliation: Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences China, Wuhan, China.|Graduate School, University of Chinese Academy of Science, Beijing, China.|Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences/Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture, Wuhan, China.
authors.forename: Chiming
authors.initials: C
authors.lastname: Gu
authors.affiliation: Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences China, Wuhan, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences China, Wuhan, China.
authors.forename: Ibrahim
authors.initials: I
authors.lastname: Mohamed
authors.affiliation: Institute of Vegetable, Wuhan Academy of Agricultural Science and Technology, Wuhan, China, China.
authors.forename: Runhua
authors.initials: R
authors.lastname: Zhang
authors.affiliation: Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences China, Wuhan, China.
authors.forename: Xiao
authors.initials: X
authors.lastname: Wang
authors.affiliation: Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences China, Wuhan, China.
authors.forename: Xinxin
authors.initials: X
authors.lastname: Nie
authors.affiliation: Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences China, Wuhan, China.
authors.forename: Min
authors.initials: M
authors.lastname: Jiang
authors.affiliation: Department of Biochemistry and Microbiology, Rhodes University, Grahamstown, South Africa.
authors.forename: Margot
authors.initials: M
authors.lastname: Brooks
authors.affiliation: Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences China, Wuhan, China.|China Program of International Plant Nutrition Institute, Wuhan, China.
authors.forename: Fang
authors.initials: F
authors.lastname: Chen
authors.affiliation: Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences China, Wuhan, China.
authors.forename: Zhiguo
authors.initials: Z
authors.lastname: Li
mesh_terms: D000383:Agriculture / Q000379:methods*; D002244:Carbon / Q000737:chemistry*; D057965:Carbon Sequestration; D002957:Citrus / Q000254:growth & development*; D012987:Soil / Q000737:chemistry*; D014872:Water Movements
chemical_list: D012987:Soil; D002244:Carbon