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1.
李冰  周兴  陈海萍 《水土保持通报》2022,42(5):247-255,336
[目的] 分析2010—2019年中国乡村振兴与土地可持续利用耦合协调时空特征及聚集程度,为助推乡村振兴战略的完成,提高乡村富裕度,维护土地可持续利用提供依据。[方法] 以中国地区31个省为研究对象并构建指标体系,运用耦合协调度模型和空间自相关模型进行分析。[结果] ①乡村振兴与土地可持续利用水平空间分布上呈东中西梯度递减的特征,省际区域差距不断减小; ②耦合协调值主要介于0.6~0.7,属初级协调,空间分布呈现“东高西低”的特征,西、中、东部条带性的追逐趋势明显; ③全局Moran’s I指数均为正(0.484 4~0.566 4),局部聚集特征逐渐凸显,以东部的高—高聚集型和西部的低—低聚集型分布。[结论] 中国乡村振兴与土地可持续利用耦合协调度水平地域差异显著,未来在响应国家东部加快实现现代化,东北振兴,中部崛起与西部大开发的区域定位时应同时加强区域间的发展与互动,增强东部地区的辐射带动作用,提高西、中、东北地区的发展水平。  相似文献   

2.
为探究耕地多功能耦合协调演变规律及其驱动因素,该研究依据2000-2018年中国30个省级行政区统计数据,综合评价耕地“生产-生活-生态”三维功能水平并采用核密度估计和可视化制图刻画耕地多功能时空特征,进而采用耦合协调度模型分析耕地多功能耦合协调关系,最终采用地理探测器识别耕地多功能耦合协调演变的驱动因素并解析其驱动机制。研究结果表明:1)耕地生产功能水平、生活功能水平和生态功能水平分别处于[0.030,0.608]、[0.042,0.672]和[0.058, 0.897]范围,生产功能呈现上升-下降-上升波动变化,生活功能水平先上升后下降,生态功能水平则整体小幅提升,各项功能均具有极化特征。耕地生产功能、生活功能和生态功能空间格局分别呈现“东高西低”“北高南低”和“西高东低”分布特征。2)耕地多功能耦合协调水平处于[0.093, 0.554]范围,整体稳步提升但水平仍然较低,多数省份耕地多功能仍为失调状态。耕地多功能耦合协调空间格局逐渐呈现集聚提升的演化特征,东北地区、京津冀地区和长三角地区耕地多功能耦合协调水平较高,西北地区则处于较低水平。3)耕地多功能耦合协调度演变受经营主体条件...  相似文献   

3.
河南省城市化与生态环境耦合协调状态的时空格局   总被引:1,自引:1,他引:0  
[目的] 探索河南省城市化与生态环境耦合协调状态的空间聚集特征,提出相关的发展建议,为河南省城市可持续发展提供科学的参考。[方法] 通过构建城市化与生态环境评价体系,利用改进的耦合协调度模型,研究2008—2018年河南省城市化与生态环境发展水平及耦合协调度,对河南省17个地级城市耦合协调度进行时空格局分析。[结果] 2008—2018年全省耦合度值都在0.9以上,耦合协调度呈波动上升趋势;多数城市的城市化水平低于生态环境水平,各市城市化与生态环境的耦合协调度等级有基本不协调、基本协调、协调、高级协调;城镇化与生态环境耦合协调存在空间正相关性,有西部和中部耦合协调度高、东南部耦合协调度低的聚类特征。[结论] 河南省整体城镇化进程加快,经济城市化和生态环境压力分别对城市化和生态环境两大系统产生了重要影响。应加强郑州市中心城市的发展,推动河南东南部城市的发展。  相似文献   

4.
[目的] 评价湖南省水资源承载力,为区域制定水资源、社会经济发展和生态环境协调发展政策提供理论参考。[方法] 通过构建系统耦合协调度模型及综合评价指标体系,分析湖南省2009—2018年水资源—社会经济—生态环境系统耦合协调的时空演变过程。[结果] ① 2009—2018年湖南省及各市州水资源承载力除湘潭市外,均呈上升趋势,同时空间上呈现“U”型特征; ②在时间维度上,耦合协调度呈波动增长态势,耦合协调状态由初级向中级协调转变; ③从空间维度看,耦合协调度呈现:西部>东部>中部的地区差异,但总体由不均衡逐渐转向整体协同发展,其中张家界市耦合协调最好,常德市耦合协调度增长最快,湘潭、衡阳、邵阳等市处于较低水平。[结论] 湖南省水资源承载力与耦合协调发展态势较好,但时空差异显著;可从产业结构优化、节水排污科技投入、资源优势转化、绿色生态农业发展等方面加大政策支持以提高湖南省水资源承载力,实现高质量的可持续发展。  相似文献   

5.
[目的] 研究耕地可持续集约化与规模化耦合协调模式,为制定国土空间规划、乡村振兴、耕地保护等政策提供科学依据。[方法] 以内蒙古自治区为例,基于研究区2006-2021年的土地利用实际,运用熵值法构建耕地可持续集约化与规模化评价指标体系,采用多因子综合分析法对耕地可持续集约化与规模化进行测算,根据评价结果进行耦合协调性分析。[结果] 2006-2021年内蒙古耕地集约化综合水平在0.218~0.370之间,总体呈上升趋势,空间特征为东西耕地集约化水平较高,中部较低。各盟市耕地集约化水平差距较小,耕地利用程度与产出效果对耕地集约化水平影响较为显著。耕地规模化综合水平在0.433~0.532内波动,总体呈现先上升后下降的趋势,空间分布特征不规律。各盟市耕地规模化水平差距较大,耕地斑块形状与面积对耕地规模化水平贡献度较高。在过去15 a间,内蒙古耕地集约化与规模化的耦合度由磨合阶段逐步向高度磨合阶段发展,耕地集约化与规模化的耦合协调度持续增长,由濒临失调、勉强协调向初级协调、中级协调跃进,但仍有33.33 %的盟市处于勉强协调阶段,空间分布格局大致为东西部较高,中部较低。[结论] 内蒙古耕地利用水平存在优化空间,应更加注重对耕地科学利用,改善种植环境,将耕地利用与保护并重,促进内蒙古地区农业可持续高质量发展。  相似文献   

6.
[目的]分析2010—2020年广西壮族自治区土地生态安全与乡村振兴发展水平及其协调性的时空特征,旨在促进土地生态安全保护和提高乡村振兴发展水平,使二者相互促进协调发展。[方法]以广西地区14个市为研究对象并构建指标体系,运用综合测度水平与耦合协调度模型进行分析。[结果](1)研究区土地生态安全水平随着研究时间的推移呈现上升的发展态势;(2)乡村振兴发展水平总体呈先下降后上升的态势,但各城市的发展水平不尽相同;(3)协调度呈“升降不一”式的变化,协调水平呈东、西部向中部,内陆向沿海,中部向北部协调水平逐渐升高的趋势分布,刻画出“东西低,南北高”的发展格局;(4)根据14市划分所属的区域类型,应采取不同的发展方式与发展重心。[结论]广西壮族自治区土地生态安全与乡村振兴协调水平发展不稳定,后续应加强低水平协调区的土地生态安全与乡村振兴融合发展,并与惠政策、惠民生、促发展等举措相结合,提高二者协调水平,同时要稳定成熟区两系统间的协调发展,以防出现滑落的迹象。  相似文献   

7.
[目的] 探究广西壮族自治区高质量发展与土地资源可持续利用耦合协调性,旨在为区域协调发展提供新思路和案例参考。[方法] 以广西的14个地级市为研究对象,运用熵权TOPSIS法、耦合度及耦合协调度模型、空间自相关分析方法定量分析2009—2018年高质量发展与土地资源可持续利用协调发展时空格局。[结果] ①广西高质量发展水平大致保持上升趋势;土地资源可持续利用水平在两次波动中上升;协调发展类型大致经历了“勉强协调、初级协调、中级协调、良好协调”4个层次。②各市高质量发展速度与土地资源可持续利用发展速度上升幅度不同;城市协调发展度由西向东、内陆向沿海逐渐升高。③研究期间广西14个地级市之间的协调发展度地域带动性不强,各市受相邻城市的影响不大。[结论] 从时间尺度上看,广西高质量发展与土地资源可持续利用水平均有提升,耦合协调度无明显变动;从空间尺度上看,各市发展速度不尽相同,空间集聚或离散程度不明显。  相似文献   

8.
[目的]科学开展村庄类型识别,为江西省兴国县国土空间总体规划编制和乡村振兴战略实施提供技术支撑和决策参考,为南方丘陵山区村庄类型识别提供经验借鉴。[方法]以村域为研究单元,分别构建村庄布局适宜性评价指标体系与乡村振兴潜力评价指标体系,采用AHP和CRITIC法组合确定指标权重,构建耦合协调度模型识别兴国县村庄类型。[结果](1)兴国县村庄布局适宜性总体水平一般,以中适宜性等级为主,空间分布差异显著,呈现出“中心城区向四周阶梯式递减”的分布特征;(2)乡村振兴潜力水平有待提高,高值区主要分布在城区周边和各镇区驻地;(3)村庄布局适宜性与乡村振兴潜力耦合度较高,协调性有待提高,耦合协调度一般,初级耦合协调村庄最多;(4)将兴国县村庄类型识别为城郊融合类、集聚发展类、存续提升类、特色保护类和搬迁撤并类5类。[结论]村庄布局与当地的地形、社会经济发展有着紧密的联系,乡村振兴潜力与布局适宜性呈现出明显的正相关关系,应针对不同村庄类型提出不同发展策略。  相似文献   

9.
唐璐  李娟  王丹丹  郭佳瑶 《水土保持通报》2023,43(1):235-243,262
[目的] 研究贵州省贵阳市高质量发展与水资源保护利用之间耦合协调状况,为进一步推动西南喀斯特山区水资源高效供给与水生态环境维护,统筹推进区域高质量发展提供科学依据。[方法] 运用综合评价、耦合协调度、空间自相关和地理探测器等模型,对2010—2020年贵阳市高质量发展与水资源保护利用耦合协调水平、时空分异特征和影响因素进行分析。[结果] 贵阳市高质量发展水平呈显著提升态势,而水资源保护利用水平呈波动下降趋势。两者的耦合协调度呈现提高态势,经历了濒临失调—勉强失调的演变过程,空间上整体呈现中、西部较高,东部较低的分布格局;二者具有显著空间正相关关系,高高聚集与低高聚集空间关联较明显。影响因子变动较大,且双因子增强效应与非线性增强效应明显。[结论] 贵阳市高质量发展与水资源保护利用之间相互依赖程度日益增强,未来应增强创新第一动力作用,优化水资源利用结构,提升“三水”统筹治理能力,促进区域协调高质量发展。  相似文献   

10.
河北省城市土地集约利用与城市化的耦合协调度分析   总被引:4,自引:0,他引:4  
基于城市土地集约利用与城市化的耦合协调特征,构建耦合协调度模型和相对发展度评价模型,对河北省11个市2001-2010年的耦合协调发展度和相对发展度进行了测算分析.结果表明:从耦合协调度的时序特征来看,系统逐渐从颉颃期、磨合期向协调期发展,城市土地集约利用与城市化趋于同步发展;从空间特征来看,耦合协调度呈现出片状分区集聚的特征,东部沿海城市耦合协调水平较高,北部地区耦合协调水平较低,中部地区发展平稳.随着时间的推进耦合协调关系逐渐优化.  相似文献   

11.
低氮和干旱胁迫对富士和秦冠生长及氮素利用的影响   总被引:2,自引:2,他引:0  
【目的】以富士(Fuji)、 秦冠(Qinguan)嫁接在平邑甜茶(Malus hupehensis Rehd.)上的当年生盆栽苗为试验材料,采用砂培方法,研究了缺氮胁迫和干旱对富士和秦冠生长情况、 光合参数、 植株各部位氮磷钾含量及氮素利用效率的影响,分析比较了低氮干旱条件下富士和秦冠生长及氮素利用的差异,以期为果树生产高效肥水利用提供理论指导。【方法】试验共设四个处理: 正常氮正常水(ZZ)、 低氮正常水(DZ)、 正常氮干旱(ZG)、 低氮干旱(DG)。氮素和水分均设置两个水平,分别为正常氮(6 mmol/L NO-3-N)、 低氮(0.3 mmol/LNO-3-N)、 正常供水(保持盆中砂子相对含水量为饱和含水量的80%~85%)、 干旱处理(保持盆中砂子相对含水量为饱和含水量的60%~65%)。【结果】富士和秦冠的生物量(茎和叶)、 株高茎粗等生长指标以及光合速率、 气孔导度、 蒸腾速率均为正常氮正常水(ZZ)>低氮正常水(DZ)>正常氮干旱(ZG)>低氮干旱(DG),并且相对应处理下秦冠的以上指标均高于富士;正常供水下,缺氮处理使富士、 秦冠的根冠比比正常氮处理均有所增加,富士提高了2.05%,秦冠提高了22.40%。富士和秦冠的氮、 磷、 钾含量均表现出正常氮正常水(ZZ)>低氮正常水(DZ)>正常氮干旱(ZG)>低氮干旱(DG); 氮、 钾元素含量在植株各部位的分布顺序依次是叶>根>茎,磷元素则是根>叶>茎;光合氮素利用效率(PNUE)和氮素利用效率表现为秦冠处理之间差异极显著,富士处理之间差异不显著;秦冠的PNUE和NUE明显高于富士,在低氮正常水(DZ)处理下,秦冠氮肥利用率比富士高42.07%,在低氮干旱(DG)处理下高64.14%;低氮胁迫下富士和秦冠的NUE显著提高,并且秦冠提高的幅度高于富士。【结论】施用氮肥能够显著提高富士与秦冠的干物质量,同等水肥条件下,秦冠生长优于富士;水分亏缺会减少叶片对氮的吸收,干旱条件下适度增施氮肥,可提高果树的抗旱能力;低氮干旱胁迫下秦冠的生长指标、 光合指标及氮素利用效率指标均优于富士,表现出较强的抗低氮干旱胁迫的能力。  相似文献   

12.
Staff members of the Department of Botany of Palacký University in Olomouc and Gene Bank Department – Workplace Olomouc, Research Institute of Crop Production in Prague, Czech Republic, conducted an expedition in seven European countries (Austria, Czech Republic, France, Germany, Italy, the Netherlands, Switzerland) in August/September 1999 to collect wild Lactuca spp. germplasm and study its geographic distribution, ecology and biodiversity. During the mission, more than 600 locations were visited resulting in the collection of 602 seed samples (accessions) of wild Lactuca species and 13 seed samples of related genera (Chondrilla and Mycelis). Lactuca serriola f. serriola, L. serriola f. integrifolia, L. saligna and L. viminea subsp. chondrilliflora were prevalent in southern Europe (Italy, France), however, only L. serriola was common in central and western Europe (Austria, Czech Republic, Germany, Netherlands, Switzerland). The greatest diversity of Lactuca species was found in France, where also the most seed samples (165) were collected. The most characteristic habitats with a high density of Lactuca spp. populations were observed along roads and highways, grassy ditches, ruderal communities, and dust-heaps. Natural infections by powdery mildew (Erysiphe cichoracearum) and downy mildew (Bremia lactucae) on some wild Lactuca spp. were observed. Recent observations concerning the geographic distribution, population structure, habitats, and natural occurrence of diseases of Lactuca spp. are discussed. This assemblage of genetic resources of Lactuca spp. can serve as the basis of future studies of species diversification, spatial population structure, plant microevolution, domestication processes, and genetic variability of host-parasite interactions.  相似文献   

13.
Laser-induced breakdown spectroscopy (LIBS) is a new technique for the analysis of plant material. This study investigates the application of LIBS to pasture-based plant samples. The LIBS measurements were obtained from pelletized pasture samples (100 samples) that had been also analyzed by inductively coupled plasma–optical emission spectroscopy (ICP-OES) following microwave digestion for calibration and comparison purposes. Comparisons for elements sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), boron (B), phosphorus (P), and sulfur (S) showed that LIBS could be used for almost all the standard profile total elements with concentrations down to low mg/kg levels (observed error of Na: 0.024 percent, K: 0.18 percent, Mg: 0.016 percent, Ca: 0.073 percent, P: 0.017 percent, Mn: 31 mg/kg, Fe: 150 mg/kg, Zn: 6.6 mg/kg, and B: 1.1 mg/kg). Elemental analysis at less than mg/kg levels was not possible using LIBS. The elements S and Cu were particularly difficult to analyze with reliability using LIBS at the concentration levels found in the plant samples. Replacing microwave digestion and subsequent ICP analysis with a direct analysis of dried plant samples using LIBS has the potential to improve the productivity and reduce the cost of testing.  相似文献   

14.
We have studied the effect of anaerobically digested (ADMSW) and composted municipal solid waste (CMSW) on mineralization and foodweb dynamics to verify the hypothesis that ADMSW would immobilize N right after addition to soil in contrast to addition with CMSW. Another hypothesis was that the mesofauna (enchytraeids and microarthropods) would stimulate N release from the decomposer community. We measured excretion of -N and urea-N from the mesofauna and hypothesized that enchytraeids would release urea. ADMSW and CMSW were amended to pots with sandy loam and barley. The pots were divided into treatments with or without mesofauna. Mesofauna, plant N and biomass, soil N and ergosterol (fungal biomass) were measured over a 113-day period of four equidistant samplings. Soil respiration, N mineralization and N release by the mesofauna were modelled from concurrent studies. ADMSW- and CMSW-treated soils initially (<20 days) immobilized N. The amendments did not increase plant growth substantially, and this was probably due to N-limitation in the early stages of plant growth. Enchytraeid abundance was about three times higher in ADMSW- than CMSW-treated soils, indicating that ADMSW contained more labile compounds, bacteria, and microfauna. The mesofauna did not affect N-content, but the cumulated -N excreted by the mesofauna was estimated to be substantial and about one-fifth of total plant N in ADMSW. An explanation for this discrepancy might be that in the absence of the mesofauna, other members of the detrivore and microbivore community performed the mesofauna’s function. Neither enchytraeids nor microarthropods excreted urea.  相似文献   

15.
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,  相似文献   

16.
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,  相似文献   

17.
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,  相似文献   

18.
“Wicked” problems are those that are complex and that change when solutions are applied. Many conflicts in conservation fall into this category. The study approached the problem of how to constrain the apparent wickedness of a problem in the conservation management of a species by using simple empirical indicators to carry out iterative assessment of the risk to a population and to document how this risk evolves in relation to the addition of new data and the implementation of management actions. Effects of high levels of uncertainty within data and also concerning population structure were examined through stochastic simulation and by exploration of scenarios. Historical trends in the example used, the Steller sea lion, showed rapid declines in abundance in some regions during the 1980s. The current total population is 130,000-150,000 Steller sea lions through Alaska and British Columbia and this number has been stable since about 1990 in spite of regional differences in population dynamics. Regional differences in the sequence of changes in the number of pups and non-pups, suggested that an internal re-distribution of juveniles could have happened between 1980 and 1990. Current productivity also appears close to the long-term mean. Stochastic population projection using various scenarios showed that, based upon this history, the risk of extinction for the population has declined and is below reasonable thresholds for considering the population to be endangered. The trends in risk suggest that management actions taken since 1990 have probably been effective. Consequently, the conservation management objectives for the Steller sea lion are probably being met. The approach provides a mechanism, based upon experience and scenario analysis, for exploring future policy options and may help to constrain the debate amongst stakeholders about the cost-benefit trade-offs associated with different options.  相似文献   

19.
Nutrient distributions under no tillage (NT) compared with conventional disk-and-bed tillage (CT) management in the warm, humid region of the southeastern USA need to be assessed so that future placement, quantity, and type of fertilizers can be altered, if necessary, to efficiently match crop demands. We determined soil-profile distributions of pH, N, P, S, K, Ca, Mg, Na, Zn, Fe, Mn, and Cu to a depth of 0.9 m at the end of 8.5 years of continuous CT and NT management on a Weswood silty clay loam (fine, mixed, thermic Fluventic Ustochrept) in southcentral Texas. Most dramatic changes occurred within the 0–0.05 m depth, where soil under NT had lower pH, Fe, and Cu than under CT, but greater P, K, Zn, and Mn. Greater P and K under NT than under CT also occurred below the till-zone (0.15–0.3 m). At a depth of 0–0.3 m, soil under NT contained greater amounts of extractable P, K, Zn, Fe, Mn, and Cu than under CT. Nitrogen fertilization had little effect on nutrient distributions, except resulting in greater extractable K at 0–0.05 m and greater nitrate at 0–0.15 m. Few changes in soil-profile distributions were observed for extractable S, Ca, Mg, and Na. Long-term continuous use of NT on this fine-textured, high-fertility (except for N) soil had no apparent adverse effects on nutrient distributions relative to CT, but enhanced conservation and availability of P, K, Zn, Fe, Mn, and Cu near the soil surface where crop roots proliferate.  相似文献   

20.
The responses of tallgrass prairie plant communities and ecosystem processes to fire and grazing are well characterized. However, responses of invertebrate consumer groups, and particularly soil-dwelling organisms, to these disturbances are not well known. At Konza Prairie Biological Station, we sampled soil macroinvertebrates in 1994 and 1999 as part of a long-term experiment designed to examine the effects and interactions of annual fire, mowing, and fertilization (N and P) on prairie soil communities and processes. For nearly all taxa, in both years, responses were characterized by significant treatment interactions, but some general patterns were evident. Introduced European earthworms (Aporrectodea spp. and Octolasion spp.) were most abundant in plots where fire was excluded, and the proportion of the total earthworm community consisting of introduced earthworms was greater in unburned, unmowed, and fertilized plots. Nymphs of two Cicada genera were collected (Cicadetta spp. and Tibicen spp.). Cicadetta nymphs were more abundant in burned plots, but mowing reduced their abundance. Tibicen nymphs were collected almost exclusively from unburned plots. Treatment effects on herbivorous beetle larvae (Scarabaeidae, Elateridae, and Curculionidae) were variable, but nutrient additions (N or P) usually resulted in greater densities, whereas mowing usually resulted in lower densities. Our results suggest that departures from historical disturbance regimes (i.e. frequent fire and grazing) may render soils more susceptible to increased numbers of European earthworms, and that interactions between fire, aboveground biomass removal, and vegetation responses affect the structure and composition of invertebrate communities in tallgrass prairie soils.  相似文献   

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