Ecological and Landscape Effects of Ditches on Farmland Ecosystem

摘要

Ditches as important components of farmland ecosystem have definite effects, not only on hydrological cycle but also on ecology and landscape. Its irrigation and drainage functions were widely accepted, while ecological and landscape functions were seldom studied. Depended on the investigation combined with field and lab experiments, three main effects were proved in this paper. Firstly, ditches could intercept, absorb and transform non-point source pollutants from agriculture, and the capacity varied intensely with seasons. Furthermore, three kinds of ditches-soil ditch, brick ditch and concrete ditch were compared to learn that brick ditch was recommended to apply in construction of hydraulic engineering. Secondly, ditches could increase the ecosystem biodiversity and offer sorts of ecological service functions. Thirdly, ditches also had landscape effects evaluated by five indexes -quantity of plaque, area and shape, density of fields and network connectivity. Therefore, the ecological and landscape functions of ditches should be paid great attention. In the future, ecological ditches should be recommended to satisfy both hydrology and environment demands.