JOURNAL OF NATURAL RESOURCES ›› 2017, Vol. 32 ›› Issue (5): 755-764.doi: 10.11849/zrzyxb.20160506

• Resource Ecology • Previous Articles     Next Articles

Effects of Patterns of Returning Straw to Field on Soil Carbon Pool and Yield in Rice-wheat Double Cropping Systems

WANG Hai-hou1,3, JIN Mei-juan1,3, LU Chang-ying1,3, SHI Lin-lin1,3, ZHOU Xin-wei1,3, SHEN Ming-xing1,3, JI Guo-jun2   

  1. 1. Taihu Research Institute of Agricultural Sciences, Suzhou 215155, China;
    2. Institute of Agricultural Resources and Environments, Jiangsu Academy of Agricultural Sciences/Scientific Observing and Experimental Station of Arable Land Conservation (Jiangsu), Nanjing 210014, China;
    3. Key Scientific Observation & Experiment Station Paddy Field Eco-environment, Suzhou, Ministry of Agriculture, Suzhou 215155, China
  • Received:2016-05-16 Revised:2016-09-11 Online:2017-05-20 Published:2017-05-20
  • Supported by:
    Public Welfare and Industry Special Fund Project of the Ministry of Agriculture, No.201503122; Jiangsu Province Science and Technology Support Project, No.BE2013334; Jiangsu Province Agricultural Science and Technology Innovation Fund Projects, No.CX(12)1002

Abstract: Straw returning helps to decrease the environment pollution, moreover, the rational utilization of straw resources benefits sustainable development of soil fertility, soil conservation, and the agricultural ecosystem. An eight-year field experiment was conducted in Suzhou City, Jiangsu Province to study the effect of different patterns of straw returning to field on labile organic (LOC), carbon pool management index (CPMI) and crop yields in a typical rice-wheat rotation region—the Taihu Lake region. The experiment consisted of four patterns of returning straw to the field: rice straw alone (named as “R”), wheat straw alone (named as “W”), straw of both rice and wheat (named as “RW”) and no straw returning to field (CK). The results indicated that returning straw significantly increased the content of total organic carbon (TOC), LOC, and non-labile organic (NLOC) at the soil depth of 0-20 cm interval compared to no straw returning treatment. The TOC significantly increased by 15.34%-16.97%, and the LOC content significantly increased by 16.62%-27.39% (P<0.05). No significant difference on TOC or NLOC was observed among different treatments. There were no significant differences of LOC, CPI, CPMI between the treatments of RW and R, while the value of LOC, CPI, CPMI of RW were higher in the treatment of W. The mean rice yield increased by 4.53% in RW and 4.07% in R treatment respectively compared to CK treatment (P<0.05), and no significant difference was observed between W and CK treatments. There were no significant differences of LOC between RW and R treatments (P>0.05), while significant differences were observed between the treatments of RW and W (P<0.05). LOC and CPMI were significantly correlated to the mean yield of rice (P<0.05), while they were not correlated with mean yield of wheat (P>0.05). It was concluded that compared with the mode of returning both rice and wheat straws to field, the mode of only returning rice straw to field in the wheat growing season does not affect the crop yield stability and soil fertility improvement. However, it is recommended to reduce or avoid returning wheat straw in a rice-wheat double cropping system in South China.

Key words: carbon pool management index, labile organic carbon, patterns of straw returning to field, rice-wheat double cropping system, yield, soil

CLC Number: 

  • S158.5