Effects of the organic matter content on the stability of the soil hydraulic conductivity
Guo Huichao, Shao Ming'an, Fan Jun
(1. College of Resources and Environment, Northwest A&F University, 712100, Yangling, Shaanxi, China;
2. Institute of Geographical Sciences and Natural Resources Research,Chinese Academy of Sciences,100101,Beijing, China;
3. Institute of Soil and Water Conservation, Chinese Academy of Science and Ministry of Water Resources, 712100, Yangling, Shaanxi, China)
Abstract:Soil saturated hydraulic conductivity (KS) is an important hydraulic parameter of water cycle and soil erosion model, and it is also an important indicator of the improvement of soil structure. The objective of our study is to investigate the effects of organic fertilizers on KS for sandy soil and Lou soil. The content of organic fertilizers in the soil was set as 0%, 5%, 10%, 15%, 20%, 25% and 30%. Three levels were designed for soil density (depending on trial of packing). Each treatment had five replicates. Soil columns with constant head of water were used to determine KS. The results showed that 1) KS decreased with the increase of organic fertilizer content. The effects of organic fertilizer content on KS of sandy soil and Lou soil were different. KS of sandy soil declined linearly with the increase of organic fertilizer content, while KS of Lou soil decreased slowly as the organic fertilizer content increased. 2) Soil density would decrease when adding organic fertilizers to soil, but KS would not significantly decline with the increase of organic fertilizer content for both soils under the lower soil density condition. 3) Due to the addition of organic fertilizers, the procedure of K determination was stable, but the time spent for determination became longer. Under the lower soil density condition, the change of K over time was not stable. When soil density increased, the change of K over time would become stable for all levels of organic fertilizer content.