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71.
地理信息技术支持的“多规合一”——以常州市新北区为例 总被引:1,自引:0,他引:1
开展"多规合一"是推进生态文明建设、新型城镇化建设,落实供给侧改革的必然要求。本文以地理信息技术为基础,以土地利用规划为底盘,统一城乡规划、环保规划、农业发展规划等的空间基础;以经济社会发展规划为目标协调各规划,划定永久基本农田保护红线、生态保护红线、城市开发边界,实施严格的空间管控。最后,以常州市新北区为试验区,分析各规划的差异并落实重点项目,引导国土空间有序开发,优化资源空间配置,形成国土空间开发规划"一张图"。 相似文献
72.
乌兰布和沙漠农田沙害特征及其时空变化规律 总被引:1,自引:1,他引:0
风沙严重威胁着乌兰布和沙漠农田的健康运行。通过野外调查与室内分析相结合的方法,对农田沙害形式、特征及时空变化规律进行了分析。结果表明:①流沙入侵和土壤风蚀是危害农田的主要形式,其沙源主要为绿洲内部土壤风蚀和零星分布的流动沙丘及绿洲外部的流沙前移和风沙流活动;②农田沙害具有普遍性、季节性、各向异性、累积性和影响因素的多样性等特性;③绿洲内农田土壤风蚀由绿洲边缘向绿洲中心逐渐减弱,风蚀深度和强度下降。同一林网内,则由边缘向中心增加,防护林及地埂后一定距离内表现为沉积,其余地段表现为风蚀;沙质农田较黏质农田的风蚀深度和强度大。时间变化上,表现为秋季弱,春季强的特点。 相似文献
73.
平度市国土资源局全面推进“双保”行动的探索 总被引:1,自引:1,他引:0
为应对国际金融危机,平度市国土资源局积极响应国土资源部在全国范围内部署开展的"保增长、保红线"双保行动,立足部门职能,扎实工作,加强和改善土地宏观调控新机制,有效保障扩大内需,保障重点项目用地,促进经济平稳较快发展。 相似文献
74.
2006年,国土资源部确定在全国范围内开展基本农田保护示范区建设,济南市每年设立1 333.33 hm2(2万亩)市级基本农田保护示范区,进行田、水、路、林、村综合整治。通过科学选定项目、明确建设任务、完善建设标准,逐步实现基本农田建设标准化、基础工作规范化、保护责任社会化,促进农业增产、农村增效、农民增收。 相似文献
75.
黄土高原退耕地恢复对土壤无脊椎动物多样性的影响 总被引:2,自引:0,他引:2
黄土高原退耕地在恢复过程中,植被从沙蓬(Agriophyllum arenarium)单优群落向以达乌里胡枝子(Lespedeza davurica)为优势种的群落演替,土壤无脊椎群落随着退耕年限的增加由简单向复杂化演变。退耕地土壤无脊椎动物优势类群主要为线虫、螨类、拟步甲科、象甲、土蝽科和金龟甲科等组成,土壤无脊椎动物从退耕1年的14类逐步增加到7年的28类,土壤无脊椎动物的多样性指数与退耕年限呈正相关关系。土壤无脊椎动物类群的增加前期快后期慢,土壤无脊椎动物的多样性增加主要由植被和土壤的改善决定。 相似文献
76.
中国县域耕地与农业劳动力变化的时空耦合关系 总被引:17,自引:3,他引:14
利用1996 年、2000 年和2005 年中国县域耕地与农业劳动力数据,基于GIS 技术和模型方法,分析了县域耕地面积与农业劳动力变化态势及其时空耦合特征。研究表明:① 县域耕地面积和农业劳动力变化均呈先增后减态势。1996-2000 年,耕地总量、劳动力数量分别增长2.70%和1.40%;2000-2005 年,耕地总量、劳动力数量分别减少1.51%和8.18%。②“胡焕庸线”是刻画中国耕地和劳动力变化格局的重要分界线。沿此线带状区域内因退耕还林造成耕地快速减少,而农业劳动力转移滞后;其西北部区域耕地快速增加,农业劳动力也在增长;其东南部区域耕地明显减少,而农业劳动力减少速度更快,二者呈现协调态势。③ 耕地非农化进程中县域劳动力转移效率呈下降趋势。1996-2000 年和2000-2005 年,全国分别有447 个和505 个县域的耕地减少和劳动力转移呈良性变化,90%的县域劳耕弹性系数(LFEC) 的中位数分别为4.58 和2.97。④ 基于SOM自组织特征映射神经网络聚类方法,可将1996-2005 年中国县域耕地与劳动力变化的耦合特征划分为9大类型区。多情景模拟分析表明,2005-2015年的LFEC趋势值为2.55。 相似文献
77.
Understanding of the Common Land Model performance for water and energy fluxes in a farmland during the growing season in Korea 总被引:1,自引:0,他引:1
The Common Land Model (CLM) is one of the most widely used land surface models (LSMs) due to the practicality of its simple parameterization scheme and its versatility in embracing a variety of field datasets. The improved assessment of land surface water and energy fluxes using CLM can be an alternative approach for understanding the complex land–atmosphere interactions in data‐limited regions. The understanding of water and energy cycles in a farmland is crucial because it is a dominant land feature in Korea and Asia. However, the applications of CLM to farmland in Korea are in paucity. The simulations of water and energy fluxes by CLM were conducted against those from the tower‐based measurements during the growing season of 2006 at the Haenam site (a farmland site) in Korea without optimization. According to the International Geosphere–Biosphere Programme (IGBP) land cover classification, a homogeneous cropland was selected initially for this study. Although the simulated soil moisture had a similar pattern to that of the observed, the former was relatively drier (at 0·1 m3 m?3) than the latter. The simulated net radiation showed good agreement with the observed, with a root mean squared error (RMSE) of 41 W m?2, whereas relatively large discrepancies between the simulation and observation were found in sensible (RMSE of 66 W m?2) and latent (RMSE of 60 W m?2) heat fluxes. On the basis of the sensitivity analysis, soil moisture was more receptive to land cover and soil texture parameterizations when compared to soil temperature and turbulent fluxes. Despite the uncertainty in the predictive capability of CLM employed without optimization, the initial performance of CLM suggests usefulness in a data‐limited heterogeneous farmland in Korea. Further studies are required to identify the controls on water and energy fluxes with an improved parameterization. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
78.
Abstract Agricultural use and related water erosion may lead to significant changes in the sedimentological and hydrological characteristics of watersheds, and therefore negative consequences for rural development. This research aimed to put present-day soil erosion of the important Mejerda catchment into a historical context. The catchment of Wadi Mejerda in northern Tunisia has experienced soil erosion due to weather and human impacts for thousands of years. We used historical texts and results from archaeological research that go back to 1000 BC, as well as data collected during the last century. Soil erosion from different types of agricultural landscape management was analysed together with information on the soils' production potential, the hydrographic network and flood frequency. The results showed that water erosion has increased the hydrographic network by 65 km and increased the deltaic plain by as much as 15 km2/century. However, soil productivity has decreased significantly. Moreover, due to in channel sedimentation and river choking, the number of flooding occurrences has multiplied over the last century. Finally, it is shown that water erosion follows a specific cycle of degradation throughout the watershed. These findings should be considered for better water and soil management in the context of semi-arid areas. Editor Z.W. Kundzewicz Citation Jebari, S., Berndtsson, R., Lebdi, F., and Bahri, A., 2012. Historical aspects of soil erosion in the Mejerda catchment. Hydrological Sciences Journal, 57 (5), 901–912. 相似文献
79.
《Urban geography》2013,34(4):327-347
Through a case study in a village located in suburban Haikou City, Hainan Province, this article suggests the existence of a local development regime that exercises illegal farmland conversion in China's urban periphery. This regime consists not only of state officials and business investors, but also of local farmers anxious for off-farm employment. Our study highlights the broad transitions that led to the rise of local development regimes in China's urban periphery. These transitions include (1) the development of the local state, (2) farmers' changing relations with local authorities, and (3) the asymmetrical liberalization of land transaction rights in rural and urban areas. Whereas the state government still manages to intervene in the local conversion of farmland, such intervention is increasingly ineffective as economic liberalization intensifies. A series of potential policies are recommended to protect farmland and agricultural livelihoods in the context of rapid urbanization. 相似文献
80.