Soil Quality Evolution After Land Use Change From Paddy Soil to Vegetable Land
Tóm tắt
A survey was done in 15 typical villages, 150 soil and 86 vegetable plant samples were taken in Jiaxin prefecture of the Taihu Lake region, northern Zhejian province. Results indicate that after 15–20 years land use changed from the paddy rice–wheat (or oilseed rape) double cropping system, to a continuous vegetable land has caused soil quality dramatic change. (1) Acidification: average soil pH was 5.4; about 61% of total samples were pH < 5.5. It was 0.9 units lower than 10 years ago with same upland vegetable cultivation and was 1.2 units lower than soil pH of paddy rice–wheat (or oilseed rape) rotation. (2) Fertilizer salt accumulation: the average salt content was 0.28%, among these about 36.2% of the total samples contained more than 0.3%. (3) Nitrate N and available phosphorus (P) over accumulation: on average it was 279 mg NO3-N/kg, and 45–115 mg P/kg. Nitrate N four times higher and available P 4–10 times more than it is in present paddy rice–wheat rotation soils respectively. This has caused wide concern because of possible groundwater and well drinking water pollution by leached nitrate N and the P losses to water by runoff from vegetable lands induce surface water eutrophication.
Tài liệu tham khảo
Addiscott TM, Whitmore AP, Powlson DS. 1991 Farming Fertilizers and the Nitrate Problem. Wallingford, UK: CAB International.
Bija-Singh. 1996 Environmental aspects of nitrogen use in agriculture. In Tandon HLS, ed. Nitrogen Research and Crop Production. New Delhi: Fertilizer Development and Consultation Organization, pp. 159–170.
Bureau of Agriculture and Forestry, Jiaxin Prefecture. 1991 Soils of Jianxin Prefecture. Hangzhou, China: Science and Technology Press of Zhejiang, pp. 37–88.
Lagreid M, Bockman OC, Kaarstad EO. 1999 Agriculture, Fertilizers and Environment. CABI Publishing, Hydro, pp. 129, 133, 136, 147.
Li QK. 1992 Paddy Soils of China. Beijing, China: Science Press, pp. 156–162.
Liu GS. 1996 Soil Physical and Chemical Analysis and Description of Soil Profiles. Beijing, China: Chinese Standard Press.
Lu RK. 2000 Methods of Soil and Agro-chemistry Analysis. Beijing, China. Soil Science Society of China. Chinese Agricultural Science Press.
Ma LS, Wang ZX, Zhang SM. 1997 Agricultural non point pollution of watersheds in Southern Jiangsu and its counter measures. Acta Environ Sci Sinica 17(1), 39–47.
Mckenna P. 1998 Report on the commission reports on the implementation of council directive 91/676/EEC. EC, Brussels: Committee on the Environment, Public Health and Consumer Protection (A4-0284/98).
Sparks DL, Page AL, Helmke PA, Loeppert RH. 1996 Methods of Soil Analysis: Part 3, Chemical Methods Madison. WI: Soil Science Society of America.
Shrestha RK, Ladha JK. 1998 Nitrate in groundwater and integration of nitrogen-catch crop in rice-sweet pepper cropping system. Soil Sci Soc Am J 62, 1610–1619.
Spalding RF, Exner ME. 1993 Occurrence of nitrate in groundwater — a review. J Environ Qual 22, 392–402.
Tripathi BP, Ladha JK, Timsina J, Pascua SR. 1997 Nitrogen dynamics and balance in intensified rainfed lowland rice based cropping systems. Soil Sci Soc Am J 61, 812–821.
Wang DJ, Lin JH, Xia LZ. 2001 The characteristic of nitrogen leaching under paddy rice—wheat rotation system in the Taihu Lake Region, Chinese J Eco-Agric 9(1), 16–18.
WHO. 1985 Health hazards from nitrates in drinking water Report on a WHO meeting. 5-9 March 1984, World Health Organization, Copenhagen.
Zhang HC, Cao ZH, Shen QR, Wong MH. 2003 Effect of phosphorus fertilizer application on phosphorus (P) losses from paddy soils in The Taihu Lake Region. Chemosphere 50, 695–701.
Zhang WL, Tian ZX, Zhang N, Li XQ. 1996 Nitrate pollution of groundwater in northern China. Agricult, Ecosyst Environ 59, 223–231.
Zhu JG, Han Y, Liu G, Zhang YL, Shao W, Li. 2000 Nitrogen leaching loss from paddy rice/wheat rotation system in southern Jiangsu. Acta Pedol Sini 37(Suppl.), 84–92.
Xing GX, Cao YC, Shi SL, Sun GQ, Du LJ, Zhu JG. 2001 Sources of N pollution and denitrification in watersheds at the Taihu lake region. Sci China (Ser B) 31(2), 130–137.