Research in Herbosa Succession Process Based on Soil Fertility Evolution
Weed biodiversity is one of the indicators of farmland ecological environment and greatly affected by different fertilization patterns. This research program was to study weed community under different fertilization patterns in farmlands based on long term field experiments in Hubei, Anhui and Jiangxi provinces, and to explore evolution trend of weed community structure in the fields of rice, maize and wheat.
IPNI-2009-CHN-HB34
21 Mar 2014
2013 Annual Interpretive Summary
Weeds compete with crops for abiotic factors affecting growth, and this competition can result in drastic declines in crop yield and quality. These factors also play an important role in nutrient cycling, soil preservation and other ecosystem functions. Fertilization can not only affect crop growth, but also impact selection pressures on weeds. Therefore fertilization is regarded as an important component of integrated weed management program. Previous studies have demonstrated that fertilization greatly affected weed species composition, abundance, density and diversity. Study of the effect of nutrient management on weed communities is important for making better nutrient management strategies in an integrated farmland ecological system.
Based on an 11-year field experiment, Wuhan Botanical Garden of the Chinese Academy of Science studied the cumulative effects of different fertilizing patterns on the floristic composition and species diversity of farmland weeds in a wheat-soybean rotation. The field trial included five fertilizing patterns with different combinations of N, P and K fertilizers. Species composition and diversity of weed communities, plant biomass and nutrient accumulation as well as light penetration were measured. There were four dominant weeds that accounted for 90% of the total weeds. Residual weed community assembly was influenced by the topsoil-available nutrients in the order P > N > K. Competition for nutrients and solar radiation between crops and weeds constitute indirect effects on the changes in weed community composition and species diversity. The species diversity indices (species richness, Shannon-Winner Index, Pielou Index and Simpson Index) showed quadratic function relationship with light transmittance. Balanced fertilization showed an efficient inhibiting effect on weeds. The authors believe that balanced fertilization has a beneficial effect on farmland environment because it can better support crop yield and suppress competition from diverse weed species.