Taking the practical experience of Lianjie Town, Weiyuan County for example, this paper analyzed regional characteristics of the low hilly areas in Sichuan and interaction mechanism of "industrialization and urba...Taking the practical experience of Lianjie Town, Weiyuan County for example, this paper analyzed regional characteristics of the low hilly areas in Sichuan and interaction mechanism of "industrialization and urbanization", explored the path for the interaction between industrialization and urbanization from 5 perspectives, namely accelerating industrial upgrading, optimizing industrial structure, breaking through the dual system, industry back-feeding town, and protecting ecological background.展开更多
Based on the survey data and statistical information on farmers,we conduct comparative analysis of land use behavior of farmers in the Jianghan Plain and the hilly areas of Xianning City in Hubei Province.We find that...Based on the survey data and statistical information on farmers,we conduct comparative analysis of land use behavior of farmers in the Jianghan Plain and the hilly areas of Xianning City in Hubei Province.We find that the utilization rate of agricultural land and level of agricultural labor output in the plain areas are higher than in the hilly areas;at the same time,the degree of mechanization of agricultural land utilization and farmers'land use scale are larger in the plain areas.But the crop type in the plain areas is single,and the decline rate of the growing area of food crops is higher in recent twenty years;meanwhile,the material input costs and opportunity cost of labor for the agricultural land utilization in the plain areas are greater than in the hilly areas.展开更多
Documenting the recovery of hydrologic functions following perturbations of a landscape/watershed is important to address issues associated with land use change and ecosystem restoration. High resolution LiDAR data fo...Documenting the recovery of hydrologic functions following perturbations of a landscape/watershed is important to address issues associated with land use change and ecosystem restoration. High resolution LiDAR data for the USDAForestServiceSanteeExperimentalForestin coastalSouth Carolina,USAwas used to delineate the remnant historical water management structures within the watersheds supporting bottomland hardwood forests that are typical of the re- gion. Hydrologic functions were altered during the early1700’s agricultural use period for rice cultivation, with changes to detention storage, impoundments, and runoff routing. Since late1800’s, the land was left to revert to forests, without direct intervention. The resultant bottomlands, while typical in terms of vegetative structure and composition, still have altered hydrologic pathways and functions due to the historical land use. Furthermore, an accurate estimate of the watershed drainage area (DA) contributing to stream flow is critical for reliable estimates of peak flow rate, runoff depth and coefficient, as well as water and chemical balance. Peak flow rate, a parameter widely used in design of channels and cross drainage structures, is calculated as a function of the DA and other parameters. However, in contrast with the upland watersheds, currently available topographic maps and digital elevation models (DEMs) used to estimate the DA are not adequate for flat, low-gradient Coastal Plain (LCP) landscape. In this paper we explore a case study of a 3rd order watershed (equivalent to 14-digit hydrologic unit code (HUC)) at headwaters of east branch of Cooper River draining to Charleston Harbor, SC to assess the drainage area and corresponding mean annual runoff coefficient based on various DEMs including LiDAR data. These analyses demonstrate a need for application of LiDAR-based DEMs together with field verification to improve the basis for assessments of hydrology, watershed drainage characteristics, and modeling in the LCP.展开更多
文摘Taking the practical experience of Lianjie Town, Weiyuan County for example, this paper analyzed regional characteristics of the low hilly areas in Sichuan and interaction mechanism of "industrialization and urbanization", explored the path for the interaction between industrialization and urbanization from 5 perspectives, namely accelerating industrial upgrading, optimizing industrial structure, breaking through the dual system, industry back-feeding town, and protecting ecological background.
基金Supported by Humanities and Social Sciences Research Project of Ministry of Education(11YJAZH038)Research Project of South-Central University for Nationalities(CSY12043)
文摘Based on the survey data and statistical information on farmers,we conduct comparative analysis of land use behavior of farmers in the Jianghan Plain and the hilly areas of Xianning City in Hubei Province.We find that the utilization rate of agricultural land and level of agricultural labor output in the plain areas are higher than in the hilly areas;at the same time,the degree of mechanization of agricultural land utilization and farmers'land use scale are larger in the plain areas.But the crop type in the plain areas is single,and the decline rate of the growing area of food crops is higher in recent twenty years;meanwhile,the material input costs and opportunity cost of labor for the agricultural land utilization in the plain areas are greater than in the hilly areas.
文摘Documenting the recovery of hydrologic functions following perturbations of a landscape/watershed is important to address issues associated with land use change and ecosystem restoration. High resolution LiDAR data for the USDAForestServiceSanteeExperimentalForestin coastalSouth Carolina,USAwas used to delineate the remnant historical water management structures within the watersheds supporting bottomland hardwood forests that are typical of the re- gion. Hydrologic functions were altered during the early1700’s agricultural use period for rice cultivation, with changes to detention storage, impoundments, and runoff routing. Since late1800’s, the land was left to revert to forests, without direct intervention. The resultant bottomlands, while typical in terms of vegetative structure and composition, still have altered hydrologic pathways and functions due to the historical land use. Furthermore, an accurate estimate of the watershed drainage area (DA) contributing to stream flow is critical for reliable estimates of peak flow rate, runoff depth and coefficient, as well as water and chemical balance. Peak flow rate, a parameter widely used in design of channels and cross drainage structures, is calculated as a function of the DA and other parameters. However, in contrast with the upland watersheds, currently available topographic maps and digital elevation models (DEMs) used to estimate the DA are not adequate for flat, low-gradient Coastal Plain (LCP) landscape. In this paper we explore a case study of a 3rd order watershed (equivalent to 14-digit hydrologic unit code (HUC)) at headwaters of east branch of Cooper River draining to Charleston Harbor, SC to assess the drainage area and corresponding mean annual runoff coefficient based on various DEMs including LiDAR data. These analyses demonstrate a need for application of LiDAR-based DEMs together with field verification to improve the basis for assessments of hydrology, watershed drainage characteristics, and modeling in the LCP.
