Improving Soil Quality (Ultisols) within Watershed Agroecosystems in Subtropical China. (5116)
Authors:
S. Wu* - Nanjing Agricultural Univ.
S. Xu - Nanjing Agri. Univ.
F. Hu - Nanjing Agri. Univ.
H. Li - Nanjing Agri. Univ.
P. Gersper - Univ. of California
Abstract:
The improvement of the quality of a soil belonging to Ultisols could be achieved by an ecosystem approach to sustainable agriculture, which was accomplished by organizing the small watershed with diversified and fast growing trees, fruit trees, tea gardens, rain-fed and anti-drought crops, forage crops, cover crops, as well as houses for raising pigs for producing manure and compost. The strategy for improving the soil quality focused on internal nutrient cycling and optimum input of chemical fertilizer N and P. The object was to enchance soil chemical properties and fertility, such as soil pH, SOC, CEC, available nutrients, and to improve soil physical properties, especially for the nature and quality of micro-aggregates and water storage capacity, and to activate soil organisms' activities. Techniques used included: the combinations of organic and inorganic fertilizers, sole application of manure, direct burying crop residues, no-tillage, intercropping with legume and mustard family cover crops, and liming. Changes of SOC, CEC, TN, available P, microaggregates, bulk density, water holding
capacity,available soil water,and earthworm population density were selected as indicators for assessing the change of the soil quality. Positive effects were obtained after various field experiments for 3-4 years. Modification of local microclimate to reduce soil water evaporation rate was also achieved.
Speaker Information: Shanmei Wu, Nanjing Agricultural Univ., 2951 Derby St. #228, Berkeley, CA 94705;
Phone: 510-666-1262; E-mail: [email protected]
Session Information: Tuesday, November 2, 2004, 2:00 PM-4:00 PM Presentation Start: 2:00 PM (Poster Board Number: 1754)
Keywords: microclimate; soil organic carbon and available P; soil quality; Utisols
