WANG Rong-mei 1,2, YANG Fang 1, XU Liang 2, LIU Zhong-tang 3, ZHANG Xiao-qin 2, WANG Hai-xiao 3, LEE Xin-qing 1,*
(1. State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China;
2. The Kashgar Meteorological Bureau, Xinjiang Uygur Autonomous Region, Kashgar 844099, China; 3. The Kashgar Agricultural Technology Promotion Center, Xinjiang Uygur Autonomous Region, Kashgar 844099, China)
Abstract: Agriculture is the foundation for the economic and social development of the Xinjiang Uygur Autonomous Region, China, and the agricultural production involves 95% of its whole population and thus is crucial to the national unity, the harmony of the society and the livelihood of the people. At the explosion of population and quick expansion of cities in recent decades in the region, new technologies are imperatively needed to promote the agricultural productivity in the oasis fields. Based on these understandings, this study applied biochar of wheat straw to the fields of cotton, a predominant economic plant in Xinjiang, and observed the effect on soil pH, water holding capacity, as well as the growth and production of the plant. The results indicated that the biochar improved significantly the water- holding capacity of soil, so much as doubling the water content at 10% application rate (w/w). Meanwhile, the application of charcoal also increased soil alkalinity, by as much as 0.36 on average at the same application rate. This effect, however, was subdued quickly with leaching incurred in irrigation or precipitation. By mixing the biochar with soil at the top 15- cm depth, the charcoal increased the net productivity by 26% at the 5% application rate. The enhancement of productivity results geochemically from the nutrients and water holding capacity increased by the application of biochar, which apparently helped improve the plant growth by increasing the height, the number of stems and cotton buds in the individual stand. Much different from the mixing method, the amendment of charcoal by burying in ditches dug in between the lines of the cotton seedlings only slightly increased the production. This application may cut down some of the roots in digging and/or impair, the growth due to high alkalinity once the newly grown roots reached the bulk biochar buried in the ditch, and thus caused the wilting of the plants. These findings suggested that biochar holds the high potential as a new technology in promoting the productivity in the oasis so long as the application method is appropreated. This study contributed directly to the cotton production in Xinjiang oases, but also helped with the agricultural management in the arid northern part of China.
Key words: biochar; oasis agriculture; cotton production; soil pH; saline-alkali field
EARTH AND ENVIRONMENT Vol. 42, No.6, Tot No.302, 2014, Page 757-763
