Abstract

Balances of major nutrients such as nitrogen (N), phosphorus (P), and potassium (K) in small-scale farming systems are of critical importance to nutrient management and sustainable agricultural development. Mass balances of N, P, and K and some of their influencing factors were studied for two years from July 2003 to July 2005 on small-scale vegetable-farming systems in two contrasting peri-urban areas (Nanjing and Wuxi) of the Yangtze river delta region of China. This balance approach considered organic fertilizer inputs (cow manure, pig manure, and human biosolids), inorganic fertilizer inputs (urea, composite fertilizer, and phosphates), irrigation water, and atmospheric deposition; and considered outputs by vegetables. Input via organic fertilizers was significant for all element balances in the Nanjing area. Inorganic and organic fertilizer, particularly inorganic fertilizer, contributed major nutrient inputs to the system in the Wuxi area. Compared with nutrient output by vegetables, there were significant surpluses of N and P on two vegetable farm systems. Furthermore, N surplus in the Nanjing area was higher than that in the Wuxi area with an inverse relationship to P surplus. In contrast, the general trend of K balances was negative on both sites; hence, the nutrient use efficiency was significantly lower for N and P than K. The nutrient imbalance may be attributed to the differences between fertilizer types and management modes driven by social economic status differences among farmer households. The large N and P net excess creates an environmental threat because of potential losses to ground or surface waters, whereas negative K balance creates soil fertility risks. The results highlight researchers' and farmers' need to develop rational fertilization technology to optimize nutrient management on vegetable farmlands to promote sustainable agricultural development in peri-urban areas.

Keywords

nutrient balance; vegetable farming systems; peri-urban areas; socio-economic status; China

Published in

Nutrient cycling in agroecosystems
2008, Volume: 81, number: 3, pages: 203-218
Publisher: SPRINGER

SLU Authors

• Öborn, Ingrid

  • Department of Soil Sciences, Swedish University of Agricultural Sciences
    

Sustainable Development Goals

SDG2 End hunger, achieve food security and improved nutrition and promote sustainable agriculture
SDG12 Ensure sustainable consumption and production patterns


UKÄ Subject classification

Agricultural Science
Environmental Sciences related to Agriculture and Land-use


Publication identifier

DOI: https://doi.org/10.1007/s10705-007-9157-8

Permanent link to this page (URI)

https://res.slu.se/id/publ/21122