Ecological compensation or eco-compensation has been implemented mainly through institutional arrangement in China. In the farming-pastoral transitional zone of Inner Mongolia, eco-compensation has been implemented in two modes, one for land use abandonment and the other for productionstructure adjustment. Based on a detailed field survey, this study performs a comparative analysis of the willingness of households to accept economic compensation and consequently evaluates the effects of the two eco-compensation modes. The mode of eco-compensation for land use abandonment lacks a mechanism for generating employment opportunities and so is unsustainable. In contrast, ecocompensation for production-structure adjustment makes the pastoral and farming scales of households decrease significantly and most importantly helps to generate more job opportunities. Although this mode faces households with more market risk, it provides an effective means for resolving conflicts between ecosystems restoration and regional socio-economic development.
The lateral distributions of depth-averaged velocity in open compound channels with emerged and submerged vegetated floodplains were analyzed based on the analytical solution of the depth-integrated Reynolds-Averaged Navier-Stokes equation with a term to account for the effects of vegetation.The three cases considered for open channels were two-stage rectangular channel with emerged vegetated floodplain,rectangular channel with submerged vegetated corner,and two-stage rectangular channel with submerged vegetated floodplain,respectively.To predict the depth-averaged velocity with submerged vegetated floodplains,we proposed a new method based on a two-layer approach where flow above and through the vegetation layer was described separately.Moreover,further experiments in the two-stage rectangular channel with submerged vegetated floodplain were carried out to verify the results.The analytical solutions of the cases indicated that the corresponding analytical depth-averaged velocity distributions agree well with the simulated and experimental prediction.The analytical solutions of the cases with theoretical foundation and without programming calculation were reasonable and applicable,which were more convenient than numerical simulations.The analytical solutions provided a way for future researches to solve the problems of submerged vegetation and discontinuous phenomenon of depth-averaged velocity at the stage point for compound channels.Understanding the hydraulics of flow in compound channels with vegetated floodplains is very important for supporting the management of fluvial processes.
ZHANG MingwuJIANG ChunboHUANG HeqingGerald Charles NANSONCHEN ZhengbingYAO Wenyi
