中国重点农区乡村地域功能演变及其影响机理——以江汉平原为例   总被引：6，自引：1，他引：5  

卓蓉蓉  余斌  曾菊新  郭新伟  王明杰 《地理科学进展》2020,39(1):56-68

乡村振兴战略的实施亟需提炼不同乡村地域类型的发展路径。论文构建了乡村地域生产、生活、生态功能测度指标体系,刻画江汉平原乡村地域功能演化特征;基于空间计量模型探析了江汉平原乡村地域功能演变的影响因素及作用机理。研究结果发现：① 江汉平原各县域乡村地域功能指数均呈现出不同程度的增长趋势,生产、生活、生态功能指数分别增长78.26%、34.25%、9.68%;生产功能增长主导和生活功能增长主导是乡村地域综合功能提升的主要类型。② 江汉平原乡村地域功能存在显著的空间非均衡分布格局,生态功能主导型县域主要分布于北部边缘地区,生活功能主导型县域集中分布于中部和南部地区,生产功能主导型县域分布相对零散;生态功能和生活功能主导江汉平原乡村地域功能的空间变化。③ 外源驱动对江汉平原乡村地域功能变化主要表现为负向作用,内生响应主要表现为正向作用;乡村生产功能受外源驱动和内生响应的影响程度最高,乡村地域综合功能被影响程度次于乡村生产和生活功能;乡村地域综合功能和生产、生活功能具有正向的空间溢出效应。探寻农产品主产区乡村地域功能演变的影响因素及作用机理,有助于识别差异化的乡村发展路径,为乡村振兴战略实施提供参考依据。  相似文献   

七里海潟湖湿地近期演变分析及生态修复研究          下载免费PDF全文

邢容容  刘修锦  邱若峰 《海洋开发与管理》2019,36(11):64-68

海岸潟湖是半封闭系统,往往被海岸沙丘、沙嘴或沙坝阻碍了淡水与海洋的流通,也是重要的栖息地,如湿地、红树林、盐沼和海草地等。在过去的30年,七里海潟湖湿地生态系统遭受了严重的干扰。文章基于1987年、2000年、2010年和2017年的遥感数据,开展了七里海潟湖湿地类型变化研究。结果表明:1987年以来,七里海潟湖湖盆和沼泽面积持续减少,主要原因是向养殖池塘和稻田转变。围堰养殖、稻田开发、渔港及防潮闸建设等导致潟湖淤积严重,湖盆面积萎缩,水质恶化。为了更好地开发和利用潟湖湿地资源,提出了生态修复工程与措施。  相似文献   

海岸带土地利用格局演化及多情景开发模拟¬——以宁波市为例     

应超  李加林  钟捷  赵蓉蓉  陈宇昕  甘付兵 《海洋通报》2024,(2):289-300

海岸带土地在高强度开发下变化显著,明确其演化规律和驱动因子,为优化土地利用结构和合理利用海岸带资源提供重要依据。基于1990－2020年7期土地利用数据,利用土地利用强度指数、地理探测器模型等方法,分析宁波市海岸带土地利用格局演变特征及驱动因子;同时利用CA-Markov模型对2025年和2030年宁波市海岸带土地利用格局进行模拟。结果表明：（1）宁波市海岸带土地利用类型主要为林地和耕地,土地利用格局演化明显,其中耕地面积不断减少,林地、草地、水域和未利用地面积发生小幅度动荡,建设用地面积快速增长。（2）宁波市海岸带土地利用强度不断增加,研究区北部增长趋势明显,而南部增长速度缓慢。（3）地形和坡度是影响宁波市海岸带土地利用变化的主要自然因素,但影响程度不断减弱;GDP密度和人口密度是主要社会经济影响因素,影响强度逐渐增强;因子间交互作用类型主要为双因子增强和非线性增强,社会经济因子与自然因素中的海拔和坡度交互作用最为强烈。（4）未来宁波市海岸带土地利用变化剧烈区域将集中于杭州湾南岸、象山县东北部和宁海县南部,生态保护情景能最大程度保持土地利用结构稳定,有效缓解人地矛盾。  相似文献   

电子商务专业村空间格局演化及影响因素研究——基于2015—2020年中国淘宝村数据     

王明杰  颜梓晗  余斌  卓蓉蓉  郭新伟 《地理科学进展》2022,41(5):838-853

电子商务专业村是数字经济时代中国农村产业转型升级的新模式。论文基于2015—2020年全国淘宝村空间数据,采用GIS空间分析和地理探测器等方法探求电子商务专业村的空间格局及演化特征,揭示不同影响因素作用机理。结果表明：① 淘宝村总体空间分布格局与中国基本地理格局高度吻合,时空演化呈现由中心向外围逐渐扩散特征;② 淘宝村呈现显著的空间集聚特征,空间集聚强度逐年增强,高强度集聚范围逐年扩大,华北平原传统农区出现高强度淘宝村集聚区;③ 淘宝村呈现显著的空间聚类分异特征,空间聚类区分布相对稳定,高—高(HH)集聚区集中分布在苏南、浙江、福建的泉州、莆田和潮汕揭城市群;④ 各影响因素对淘宝村空间格局演化具有不同的解释强度,产业基础和区位条件是高作用影响因子,政府行为影响力稳步上升,社会经济影响呈“U”型变化态势,三级影响因素中第一产业增加值、农村常住人口的影响程度呈下降趋势。研究结果对推进电子商务专业村发展、深化专业村发展理论、助力乡村振兴具有重要的理论意义和实践价值。  相似文献   

关于审批证照数据库建设的初步探讨     

汪荣荣  高峰  张伟伟 《测绘与空间地理信息》2021,44(5):99-100

自然资源审批证照数据库是支撑审批政务运行的重要基础数据,通过审批证照数据库的建设,形成自然资源"审批一张图",实现以图查证,有利于提高审批服务质量,推进"最多跑一次"改革.本文以宁波的审批证照建设为实例,阐述技术路线,促进审批证照管理规范化.  相似文献   

Modelling potential hydrological impact of abandoned underground mines in the Monday Creek Watershed,Ohio     

Rongrong Wan  Desheng Liu  Darla K. Munroe  Shanshan Cai 《水文研究》2013,27(25):3607-3616

Abandoned underground mines (AUM) have caused dramatic environmental effects that are closely linked to regional sustainability. This paper explores the potential hydrological impact of AUM in the Monday Creek Watershed, a typically mined area in Appalachian region, using the Soil and Water Assessment Tool (SWAT 2005) model and Sequential Uncertainty Fitting (SUFI‐2), calibrated at both the global and local scales. The locally calibrated model better incorporates those key parameters relevant to AUM for specific sub‐basins and hydrologic response units. Data from the years 2003–2004 were used for calibration and 2005–2006 for validation. The results were quite satisfactory; both the coefficient of determination (R²) and the Nash–Sutcliffe efficiency statistic were over 0.80. The potential influences of AUM were assessed by modelling an alternative scenario assuming no AUM for the period 2003–2009. Results show that the hydrological process of lateral subsurface flow plays a dominant role in linking AUM to overall watershed hydrology. The potential hydrological impact of AUM is an increased annual lateral flow of 82.1%, and a decrease in annual surface flow by 15%, leading to an increase of 16.9% in annual water yield for the Monday Creek Watershed. The seasonal fluctuation of water yield has a similar trend to lateral flow, decreasing from March to August and increasing from August to January. Higher volume, higher flow peaks and higher recession constants characterized the hydrograph of daily streamflow from AUM. The results indicate that more emphasis should be put on lateral flow for further study of acid mine drainage and flooding control in those watersheds with AUM. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

An adaptive compromise programming method for multi-objective path optimization     

Rongrong Li  Yee Leung  Hui Lin  Bo Huang 《Journal of Geographical Systems》2013,15(2):211-228

Network routing problems generally involve multiple objectives which may conflict one another. An effective way to solve such problems is to generate a set of Pareto-optimal solutions that is small enough to be handled by a decision maker and large enough to give an overview of all possible trade-offs among the conflicting objectives. To accomplish this, the present paper proposes an adaptive method based on compromise programming to assist decision makers in identifying Pareto-optimal paths, particularly for non-convex problems. This method can provide an unbiased approximation of the Pareto-optimal alternatives by adaptively changing the origin and direction of search in the objective space via the dynamic updating of the largest unexplored region till an appropriately structured Pareto front is captured. To demonstrate the efficacy of the proposed methodology, a case study is carried out for the transportation of dangerous goods in the road network of Hong Kong with the support of geographic information system. The experimental results confirm the effectiveness of the approach.  相似文献   

山东栖霞市虎窝顶矿区金矿地质特征及矿床成因找矿方向          下载免费PDF全文

胡伟华  邱介玲  王厚琴  于森  赵贤  程蓉蓉 《山东国土资源》2014,30(7):18-22

栖霞市虎窝顶矿区金矿床位于栖霞市金山境内,为多金属硫化物石英脉型金矿床,成因上属于中温热液裂隙充填石英脉型金矿床。矿体以条带状、透镜状为主,矿体规模中等,厚度、品位变化较大,主要矿石矿物有黄铁矿、方铅矿、闪锌矿,少量黄铜矿,矿石结构以晶粒状结构、压碎结构为主,次为填隙结构、乳浊状结构、包含结构、镶嵌结构、骸晶结构、交代残余结构等,矿石构造主要有块状、网脉状、浸染状构造,其次为角砾状构造和胶状构造。矿石类型主要为原生矿石,矿体围岩主要是新太古代栖霞超单元回龙夼单元条带状细粒含角闪黑云英云闪长岩。  相似文献   

Early diagenetic behaviour of selenium in freshwater sediments     

Nelson Belzile  Yu. -Wei Chen  Rongrong Xu 《Applied Geochemistry》2000,15(10)

The vertical distributions of dissolved Se species [Se(IV), Se(VI) and organic Se] and diagenetic constituents [Fe(II) and Mn(II)] were obtained in porewater samples of two Sudbury area lakes (Clearwater and McFarlane). The sedimentary concentration profiles of total Se, Se species bound to Fe–Mn oxyhydroxides and to organic matter, and of elemental Se were also determined along with the concentrations of Fe, Mn and S in different extractable fractions. Results indicated that the concentrations of total dissolved Se in porewater samples were very low, varying from around 2.0 nM to a maximum level of 6.5 nM, while the concentrations of total Se species in the solid phase varied between 2 and 150 nmol/g on a dry weight basis. The two lakes showed striking differences in the presence of Se(IV) and Se(VI) at the sediment–water interface (SWI). In Clearwater Lake, Se(VI) was present at this interface and Se(IV) was not detectable, whereas the opposite was found in McFarlane Lake. This suggests that reducing conditions might have existed near the SWI of McFarlane Lake at the sampling time; this hypothesis was confirmed by several other measured chemical parameters. The profiles of total dissolved Se of both lakes suggest upward and downward diffusion of dissolved Se species along the concentration gradients. Assuming that no precipitation occurred at the SWI, the fluxes of dissolved Se species across the SWI in Clearwater and McFarlane lakes were estimated to be 0.108 and 0.034 nmol cm⁻² a⁻¹, respectively. These values do not include the possible losses of volatile Se species due to microbial methylation. In the reducing sediments of both lakes, the formation of elemental Se and pyritic Se were found to be important mechanisms for controlling the solubility of Se in this environment. The main geochemical processes involving Se identified in this study are: the adsorption of Se onto Fe–Mn oxyhydroxides at or near the SWI, the release of adsorbed Se by the reduction of the same oxyhydroxides and the mineralization of organic matter, and the removal of Se from porewaters to form elemental Se and a S mineral phase such as Se–pyrite or pure ferroselite.  相似文献   

基于地形指数的砒砂岩黄土区土壤侵蚀分析     

乔荣荣  韩艳  季树新  董春媛  王傲洁  常学礼 《中国沙漠》2021,41(5):175-182

地形是土壤侵蚀进程的重要控制因子,在土壤侵蚀评价中发挥着重要作用。基于地形起伏表达构建了地形指数,结合降雨侵蚀力和植被盖度等建立了基于地形指数的土壤侵蚀方程,并分析了内蒙古自治区鄂尔多斯市北部十大孔兑砒砂岩黄土区1985—2018年土壤侵蚀时空变化特征。结果表明：（1）研究区多年土壤侵蚀模数整体有下降趋势但变化差异不显著（P>0.05）,多年平均侵蚀模数为22.34 t·hm^-2·a^-1。1985年土壤侵蚀模数最大,2000年土壤侵蚀模数最小,1985—2000年呈下降趋势,2000—2018年呈上升趋势;（2）多年平均土壤侵蚀面积为2 956.07 km²,1985年土壤侵蚀面积最大,为4 047.14 km²,占总面积比例83%;2000年土壤侵蚀面积最小,为2 153.67 km²,占比44%。研究区1985—2000年以轻度、中度侵蚀强度类型为主,2000—2018年以微度、轻度侵蚀类型为主;（3）多年土壤侵蚀空间分布格局基本一致,土壤侵蚀综合指数由西至东增加,总体上呈现为东部侵蚀大于西部的特点,母哈尔沟土壤侵蚀综合指数最大,毛卜拉孔兑最小;（4）地形指数土壤侵蚀方程与通用土壤流失方程在土壤侵蚀模数和土壤侵蚀面积估算上均无显著差异（P>0.05）。  相似文献