Responses Of Litter Production Decomposition In Wheat Cultivars To Soil Nutrients In Their Habitats

Farmland ecosystem is one of the most important ecosystems in the world, which provides basic materials for human existences. In a farmland ecosystem, soil nutrient can affect plant growth, and thus, the quality and quantity of plant litters, which will also affect the process of litter decomposition. In two controlled experiments, the effects of soil nutrient on litterfall and litter decomposition of two winter wheat cultivars (Zhongmai 9 and Lunxuan 987) were studied using Homogeneous decomposition method. The results were as follows:1) Biomass, and thus, litterfall in leaf and root of the two cultivars increased with the increases in soil nutrient. However, the rates of root to shoot of the two cultivars all decreased with the increases in soil nutrient, Plants growing best in soil nutrients 0.50%, the litter production too.2) Soil nutrient affectted the decomposition of leaf litters in these two winter wheat but did not affect their root litters.3) The C:N ratios in leaf and root of the two cultivars all decreased with the increases in soil nutrient, but C:N ratio in leaf was almost lower than that in root. These were similar to C:N ratios in leaf and root litters of the two cultivars. Obviously, nutrient addition reduced the C:N ratios in leaf and root, and even, the effect of soil nutrients on C:N ratio in leaf was greater than that in root. The C:N ratios in leaf and and root of the two cultivars significantly decreased after decomposition, and thus, litter decomposition would be accelerated as C:N ratio decrease.4) N and C return in the leaf and root of the two cultivars all increased with increase in soil nutrient availability. The dependence of C and N releases in the leaf on soil nutrient availability was stronger than that in the root. The dependence of N release on soil nutrient availability was stronger than that of C release.