Control of mass flow systems for the harmonious balance of intensive utilization and environmental protection of a peatland

本研究的目的是建立一个适当的质量流管理系统，这是适合于协调技术，需要开垦农业用地，以改善粮食生产和技术，需要维持和保护泥炭地的环境和生物资源。选择北海道的Bibai泥炭地作为试验田，在约50公顷的天然泥炭地和沼泽泥炭地周围的耕地中测量和分析质量流模式，以找到合适的质量流管理系统。冬季积雪使地表高程下降最多20 cm，积雪融化后又恢复。沼泽的导热系数很小，雪在沼泽和雪的界面上不容易融化，导致地下水供水短缺。天然沼泽泥炭区 ...更多信息 这里主要覆盖着两种植物，一种是地下水位相对较高的沼泽地，另一种是地下水位相对较低的低矮竹林。该沼泽区的透射率，定义为从陆地表面到给定深度（我们选择180厘米）的水力传导率的积分，在两种覆盖植物下几乎相等。在过渡泥炭区，渗透系数表现出明显的各向异性和不可逆的收缩特性。在沼泽区，泥炭土与粘性土混合程度较高，导水率各向异性较小，N2 O气体通量与土壤中气体浓度梯度成正比。结果表明，该地区土壤热通量在高地为8 ~ 14 ng/m^2 s，在暂不耕作的稻田为2 ~ 10 ng/m^2 s，在沼泽地为0 ~ 1 ng/m^2 s，其热特征主要是由于泥炭地的热导率对含水量的依赖性很强，且与一般土壤相比其值很小。少

The purpose of this study was to construct an appropriate mass-flow-managing-system which is suitable to harmonize technologies that is required to reclaim the agricultural lands for the improvements of food productions and technologies that is required to sustain and conserve the environmental and biological resources in peatlands. Bibai peatland, Hokkaido, was selected as a test field, where the mass flow patterns both within the natural bog peat area of about 50 ha and in the cultivated agricultural lands surrounding the bog peat area were measured and analyzed to find the appropriate mass-flow-managing-system.In the natural bog peat area, the elevation of the land surface decreased at most 20cm under the accumulated snow in winter season and restored with the melt of snow. The thermal conductivity of bog was so small that the snow may not melt easily at the interface between the bog and snow, resulting in the shortage of water supply to the groundwater. The natural bog peat area wa … More s covered with mainly two kinds of plants, the bog itself where the ground water level was relatively high and the low bamboo where the ground water level was relatively low. The transmissivities of this bog area, defined by the integration of the hydraulic conductivity from the land surface down to the depth given (we chose 180 cm here), were almost equal under both covering plants. In the transient peat area, we found remarkable anisotropy of hydraulic conductivity and irreversible shrinkage behavior of them. In the fen area, the peat was more or less mixed with clay soils and the anisotropy of hydraulic conductivity was not so large.N_2O gas fluxes from the soils into atmosphere were proportional to the gradient of gas concentrations within the soil. The fluxes were estimated to be 8 to 14 ng/m^2s in the upland fields, 2 to 10 ng/m^2s in the temporary uncultivated rice fields, and 0 to 1 ng/m^2s in the bog area.The thermal feature of Bibai peatland was mainly attributed to the high dependence of their thermal conductivity on water content and to the very small values of them comparing with those of usual soils. Less