Study Of The Productivity Coupling Effect Of Farmland And Woodland On The West Of Songnen Plains

The west of Songnen plains was a area under the transitional climate from semi-arid to arid, so the area represent the major mode of land use in North-East of China. This thesis focused on the productivity coupling effect between farmland and woodland on songnen plains. By observation and construction of microclimatic elements model, then we analyzed the edge effect and discussed the mechanism of the edge effect. The results were summarized as following: (a) There was some difference between edge and interior in farmland. Except the biomass in woodland existed significant difference between edge and interior in May, no significant difference existed in other experiment-periods. By the analysis of biomass, we can draw a conclusion that boundary between farmland and woodland existed the productivity coupling effect. (b) there were no significant difference between edge and interior in woodland, by Statistical comparison of biodivercity. (c) In woodland, the physical and chemical characters of the soil gradually changed. With increasing of distance to the edge, soil water content, pH, conductivity, total N content decreased. In farmland, the physical and chemical characters of the soil represent the opposite change. The ware crest of the physical and chemical of the soil appear at spot 100 meters to the edge. From analysis of physical and chemical characters of the soil, we can draw a conclusion that the soil water content and total N content in edge of woodland gradually appear changes. So the boundary came into being water island and fertility island. (d) From the interior of woodland to the interior of farmland, the temperature gradually increased. The change extent of temperature was 3.2℃. In farmland, the velocity of temperature decreasing in area from edge to 100 meters distant to edge smaller than outside's.Depending on our research results, there exist the productivity coupling effect, which result from extending of niche in the boundary between farmland and woodland. Owing to islands of the physical and chemical characters of the soil, contents of the physical and chemical characters of the soil decreased while distance to edge increased. The potential energy of the contents product permeability in the landscape boundary, so there were ecological flow in the boundary, such as the flaw of materal, energy and organic material et al. Owing to the movement of ecological flow, the landscape boundary represent edge effect that boundary's environment different from the other's.