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1.
经济发展、资源利用和生态保护之间存在着尖锐矛盾,而生态效率概念和评价体系构建为这一问题提供了解决方案。本研究基于超Slacks-BasedMeasure模型,评价了2005–2016年中国大陆30个省份生态效率的时空特征、区域差异性,并利用面板回归模型分析了其影响因素。研究发现:(1)2005–2016年各省份生态效率在研究时段总体呈现上升态势,伴有波峰变化,但各地区生态效率水平及其变化幅度的差异较为显著。东部地区生态效率明显高于中部地区、西部地区和东北部地区。(2)通过变异系数测算表明各省份生态效率差异在逐渐缩小,但空间分布仍不均衡。从区域内差异看,西部省份区域内差异均值最高,其次为东部地区和东北部地区,中部地区区域差异最小。(3)通过生态效率影响因素研究显示,工业结构、对外开放度、城镇化、技术创新和环境规制对生态效率产生积极影响,能源消费、交通对其产生消极影响,而在不同区域生态效率的影响因素呈现不同作用力。据此,提出各地区提升生态效率的相关政策建议,为缩小绿色发展差距及加快促进区域绿色可持续协调发展提供重要的实证参考。  相似文献   

2.
Urban agglomerations in China have become the strategic core of national economic development and the main component of the new type of urbanization. However, they are threatened by a series of eco-environmental problems and challenges, including the severe overexploitation of natural resources. Eco-efficiency, which is defined as accomplishing the greatest possible economic benefit with the least possible resource input and damage to the environment, is used as an indicator to quantify the sustainability of urban agglomerations. In this work, a traditional data envelopment analysis(DEA) model with a slack-based measurement(SBM) model of undesirable outputs, was used to assess and compare the economic efficiency and eco-efficiency of four major urban agglomerations in eastern China(UAECs) in 2005, 2011, and 2014. The spatio-temporal characteristics of the evolution of urban agglomerations were analyzed. Based on the results of a slack analysis, suggestions for improving the eco-efficiency of the four UAECs are provided. The overall economic efficiency of urban agglomerations located in the Shandong Peninsula, Yangtze River Delta, and Pearl River Delta displayed a V-shaped pattern(decreased and then increased). In contrast, the overall economic efficiency of the Beijing-Tianjin-Hebei urban agglomeration declined during the study period. The Beijing-Tianjin-Hebei urban agglomeration had a considerable loss of economic efficiency due to pollution, whereas the Shandong Peninsula urban agglomeration was less impacted. Overall, the eco-environmental efficiency of the four UAECs declined from 2005 to 2011 and then increased from 2011 to 2014. In addition, the urban eco-efficiency in the four coastal UAECs was characterized by different evolution patterns. The eco-efficiency was higher in the peri-urban areas of the core cities, riverside areas, and seaside areas and lower in the inland cities. The core cities of the Beijing-Tianjin-Hebei, Yangtze River Delta, and Pearl River Delta urban agglomerations were characterized by high resource consumption, economic benefit output, and eco-efficiency. In most of cities in the urban agglomerations, the emission of pollutants declined, leading to a reduction of pollutants and mitigation of environmental problems. In addition, a differential analysis, from the perspective of urban agglomeration, was performed, and concrete suggestions for improvement are proposed.  相似文献   

3.
The use of multi-perspective and multi-scalar city networks has gradually developed into a range of critical approaches to understand spatial interactions and linkages. In particular, road linkages represent key characteristics of spatial dependence and distance decay, and are of great significance in depicting spatial relationships at the regional scale. Therefore, based on highway passenger flow data between prefecture-level administrative units, this paper attempted to identify the functional structures and regional impacts of city networks in China, and to further explore the spatial organization patterns of the existing functional regions, aiming to deepen our understanding of city network structures and to provide new cognitive perspectives for ongoing research. The research results lead to four key conclusions. First, city networks that are based on highway flows exhibit strong spatial dependence and hierarchical characteristics, to a large extent spatially coupled with the distributions of major megaregions in China. These phenomena are a reflection of spatial relationships at regional scales as well as core-periphery structure. Second, 19 communities that belong to an important type of spatial configuration are identified through community detection algorithm, and we suggest they are correspondingly urban economic regions within urban China. Their spatial metaphors include the administrative region economy, spatial spillover effects of megaregions, and core-periphery structure. Third, each community possesses a specific city network system and exhibits strong spatial dependence and various spatial organization patterns. Regional patterns have emerged as the result of multi-level, dynamic, and networked characteristics. Fourth, adopting a morphology-based perspective, the regional city network systems can be basically divided into monocentric, dual-nuclei, polycentric, and low-level equilibration spatial structures, while most are developing monocentrically.  相似文献   

4.
In today's world, the innovation of science and technology has become the key support for improving comprehensive national strength and changing the mode of social production and lifestyle. The country that possesses world-class scientific and technological innovation cities maximizes the attraction of global innovation factors and wins a strategic initiative in international competition. Based on the urban zip code geodatabase, an evaluation system of urban innovation with the perspective of innovation outputs, and the spatial evolutionary mode, concerning the structure of innovation space of Shanghai and Beijing from 1991 to 2014, was developed. The results of the research indicated that the zip code geodatabase provided a new perspective for studying the evolving spatial structure of urban innovation. The resulting evaluation of the spatial structure of urban innovation using the urban zip code geodatabase established by connecting random edge points, was relatively effective. The study illustrates the value of this methodology. During the study period, the spatial structure of innovation of Shanghai and Beijing demonstrated many common features: with the increase in urban space units participating in innovation year by year, the overall gap of regional innovation outputs has narrowed, and the trend towards spatial agglomeration has strengthened. The evolving spatial structure of innovation of Shanghai and Beijing demonstrated differences between the common features during the 25 years as well: in the trend towards the suburbanization of innovation resources, the spatial structure of innovation of Shanghai evolved from a single-core to a multi-core structure. A radiation effect related to traffic arteries as spatial diffusion corridors was prominent. Accordingly, a spatial correlation effect of its innovation outputs also indicated a hollowness in the city center; the spatial structure of innovation of Beijing had a single-core oriented structure all the way. Together with the tendency for innovation resources to be agglomerated in the city center, the spatial correlation effect of innovation outputs reflected the characteristics of the evolutionary feature where "rural area encircles cities". The innovation spatial structure of Shanghai and Beijing have intrinsic consistency with the spatial structure of their respective regions(Yangtze River Delta urban agglomeration and Beijing-Tianjin-Hebei metropolitan region), which suggested that the principle of proportional and disproportional distribution of a city-scale pattern of technological and innovational activities is closely related to its regional innovation pattern.  相似文献   

5.
Resource-dependent cities are cities whose economic development depends on the exploitation and processing of natural resources. Their transformation and sustainable development are an important area of research on regional industrial development, regional economy and urban development. Since the Chinese government launched a pilot project to transform resource-dependent cities, starting with Fuxin in Liaoning Province in 2001, accurately identifying and classifying China's resource-dependent cities has become a focus of geographical research. Based on previous studies, this paper uses the theory and methods of urban function classification to analyze indicators and threshold values for identifying and classifying resource-dependent cities. It has thus identified 262 cities as being resource-dependent. Looking at the development levels, problems, characteristics and developmental direction of such cities, this paper attempts to establish a comprehensive analytical framework using the two evaluation indicators of resource security and sustainable development. It also creates a model to classify the 262 cities identified as resource-dependent cities into four types: growing cities, mature cities, declining cities and regenerating cities. The different connotations and characteristics of the city types were then analyzed. The results of this research support the delineation of scopes and categories of resource-dependent cities set out in the National Sustainable Development Plan for Resource-Dependent Cities published by the State Council, and they serve as a foundation for formulating policies on planning, classification and guidance.  相似文献   

6.
Energy eco-efficiency is a concept integrating ecological and economic benefits arising from energy utilization and serves as a measure of efficiency in the energy–environment–economy system. Using the slacks-based measure(SBM) model considering undesirable output, this study first measures the energy eco-efficiency of provinces in China from 1997 to 2012. It then analyzes the spatial distribution and evolution of energy eco-efficiency from three aspects: scale, intensity, and grain of spatial patterns. Finally, it examines the spatial spillover effects and influencing factors of energy eco-efficiency in different provinces by means of a spatial econometric model. The following conclusions are drawn:(1) The overall energy eco-efficiency is relatively low in China, with energy-inefficient regions accounting for about 40%. Guangdong, Hainan and Fujian provinces enjoy the highest energy eco-efficiency, while Ningxia, Gansu, Qinghai, and Xinjiang are representative regions with low efficiency. Thus, the pattern of evolution of China's overall energy eco-efficiency is U-shaped. Among local regions, four main patterns of evolution are found: increasing, fluctuating, mutating, and leveling.(2) At the provincial level, China's energy eco-efficiency features significant spatial agglomeration both globally and locally. High–high agglomeration occurs mainly in the eastern and southern coastal regions and low–low agglomeration in the northwestern region and the middle reaches of the Yellow River. Changes in spatial patterns have occurred mainly in areas with high–low and low–high agglomeration, with the most remarkable change taking place in the Beijing–Tianjin–Hebei region.(3) There exist significant spatial effects of energy eco-efficiency among provinces in China. For the energy eco-efficiency of a given region, spatial spillovers from adjacent regions outweigh the influence of errors in adjacent regions. Industrial structure has the greatest influence on energy eco-efficiency.  相似文献   

7.
为了响应国家十四五规划,更好地探索促进区域协调绿色发展的新战略,本文采用super-SBM模型和马尔可夫链对成渝经济圈2004–2018年的生态效率值进行了测算与时序分析,同时,利用地理加权回归模型对生态效率进行了空间分析。虽然成渝经济圈生态效率在研究期间有所提高,但其经济发展仍然是生态无效的,这意味着成渝迫切需要提高资源利用效率,促进技术创新。在研究期间,成渝经济圈的生态效率的演变呈现为“π”字形状,并伴随着“俱乐部趋同”的现象,此现象表明生态效率有保持原状的强烈趋势,说明生态效率缺乏足够的改善动力,因此很难实现跨越式转移。从空间上看,生态效率从西北向东南呈高–低–高效率分布,生态效率的时空差异缩小,但集聚效应相对较弱且呈现两极分化趋势。进一步的研究表明,城镇化发展水平、对外开放水平、技术水平、环境规制和产业结构高级化是导致生态效率空间差异的原因。成渝经济圈应针对各自弱点相应采取改善措施提高生态效率,从而促进整个区域的绿色发展。  相似文献   

8.
我国城市扩张、粮食保障和能源转型形势严峻,如何挖掘城市建成环境的绿色生产潜力、探索一条通过粮食生产和太阳能利用节约土地空间并缓解生态压力的新途径?本文不同于以往生态补偿研究大多以重点生态功能区为对象或以财税补偿机制为手段,而是创新性地建立了一种城市空间内部的生态补偿机制。本文提出城市“绿色生产性面积”作为一种从城市生态学角度来衡量城市生态承载力提升潜力的方法,它基于将城市绿色资源收入换算成相同条件下它们所能节约的生态足迹面积。首先,通过类型学方法建立绿色生产补偿策略;其次,进行城市建成环境的全要素空间清查及其绿色生产潜力分析;最后,建立不同绿色生产的生态节地效益统一核算标准,并转换为绿色生产性土地面积指标。以天津市南开区学府街道为例,通过可利用的屋顶及闲置用地进行绿色生产,补充了该区12%的建筑所占用的自然土地所能提供的生态承载力。  相似文献   

9.
以淮南市为案例,结合历次城市规划用地现状资料,利用GIS软件,动态追踪了淮南城市空间结构时空演化进程。结果表明:作为煤炭资源型城市,淮南城市空间形态较为分散,正逐步填充向紧凑布局演化;内部空间以工业用地、居住用地、商业及公共设施用地的增长为主,空间重构现象自20世纪80年代开始逐步加强,并以居住用地取代工业用地和商业及公共设施用地取代居住用地两种形式为主。在不同生命周期阶段,煤炭资源型城市空间扩展模式不同:发生期以城矿共生扩张模式为主,成长期以厂兴镇、联厂成镇、延伸扩展模式为主,中兴期以后多通过新区扩张模式来实现空间结构演化,自组织扩展模式贯穿煤炭资源型城市发展始终。最后分析了资源、自然环境、交通、产业结构以及城市规划等主要因素对煤炭资源型城市外部形态和内部空间结构演化的影响及作用机理。  相似文献   

10.
本文对中国、日本和韩国的农业文化遗产保护计划,特别是在联合国粮农组织(FAO)全球重要农业文化遗产(GIAHS)项目和国家计划实施之下的保护与发展工作进行了比较分析。研究表明,中日韩三国的GIAHS实践和国内制度推行的发展历程、认定标准、申请程序以及实施架构等方面显示出国情背景间的差异。例如,在推行GIAHS实践和国内制度的时间顺序上三国各不相同。中国在GIAHS认证数年后推出国家认定制度,日本目前只有GIAHS没有国家认定制度,而韩国在GIAHS认证之前已实施国家认定制度。因此,目前中国和韩国的GIAHS候选地是从国内认定的农业文化遗产地挑选出来的。另一方面,从认定标准可以看出中日韩三国对于农业文化遗产保护的理念有共同点,均重视农业遗产系统相关的历史意义、文化价值、合作互促、农村振兴、生物多样性保护等。因此,中日韩三国间的紧密合作以及他们的观点将对改进FAO的GIAHS认定标准、促进其更全面地适用于发展中国家和发达国家起到重要作用。  相似文献   

11.
白草广泛分布在西藏干旱、半干旱地区,其根茎系统发达,抗旱能力较强。本文以西藏12个地区的野生白草为材料,在中科院拉萨高原农业生态综合试验站研究野生白草幼苗在干旱胁迫下的生理特性,并用隶属函数法对抗旱性进行综合评价,拟筛选出抗旱能力较强的白草种类。实验采用5种不同水势(0,–0.7,–1.4,–2.1,–2.8 MPa)的PEG-6000溶液模拟干旱胁迫,测定12份白草幼苗体内丙二醛(MDA)、脯氨酸(Pro)和叶绿素等生理指标。结果表明,随着水势的下降,白草体内活性氧的产生和消除平衡受到破坏,导致膜脂过氧化,产生丙二醛,加速叶绿素的分解;通过脯氨酸等渗透调节物质从外界吸水来抵御干旱。随着干旱胁迫的加剧,丙二醛的含量总体呈上升趋势,脯氨酸和叶绿素的含量总体呈先升后降趋势。利用隶属函数法对12个地区白草幼苗的抗旱性进行综合性评价,研究得出抗旱性由强到弱依次为:谢通门林周索县当雄定日南木林吉隆林芝普兰定结隆子萨迦,表明谢通门、林周和索县白草的抗旱性较强,其是否适宜在西藏干旱、半干旱地区种植尚需进一步研究。  相似文献   

12.
本研究基于FAOSTAT数据库中尼泊尔林业数据和食物消费数据,采用实物量核算方法,依据生物产品生产性土地类型归类,研究了尼泊尔农田、森林、草地、水域及综合生态系统的消费水平、结构及生态服务消费模式的动态变化,揭示了尼泊尔生态服务消费模式演变的主要因素。研究结果表明,1961–2018年尼泊尔农田、森林、草地、水域及综合生态系统服务消费总量平均分别为7.26 Tg yr-1、6.38 Tg yr-1、1.10 Tg yr-1、0.02 Tg yr-1和14.76 Tg yr-1,均呈现波动增长态势;除年人均森林消费量波动降低外,其余生态系统和综合生态系统年人均消费量均波动增加,且增速持续增大。1961–2018年尼泊尔生态服务消费可分为1961–1984、1985–2007和2008–2018年三个时期,生态服务消费模式依次为“木–谷–奶”模式、“木–谷–蔬–根-奶-糖”模式和“木–谷–蔬–根–糖–果–奶”模式。驱动因素分析表明,生态系统供给能力(生产能力、进口能力和出口能力)和...  相似文献   

13.
近年来,海南省海口市、三亚市等地人口快速增长,引起了各界对海南省承载力的担忧,需要研究制定承载力约束和经济增长需求下的人口与资源环境政策。为此,本文选取粮食产量、农产品营养成分和水资源量指标,分别定量测算承载力;采用就业弹性系数法,设定就业弹性系数和地区生产总值增长率,估算经济增长所需人口总量;利用PADIS-INT人口预测软件,设定总生育率、净迁移率等参数,预测人口变化情况。通过研究认为,2050年前海南省人口总量不会超过水土资源的承载力上限,全省总体上不存在人口过多的问题,而是存在人口不足的风险。建议海南省采取鼓励人口增长的政策措施,提升自然资源管理和国土空间治理水平,引导人口在全省均衡发展。  相似文献   

14.
Sustainable urbanization is not only an important research topic in the field of urbanization, but also the development direction of new-type urbanization. In this paper, we construct an index system to evaluate sustainable urbanization potential with the entropy method. Results show that potential values of sustainable urbanization in most cities are not high. Cities with higher sustainable urbanization potential values are mainly located in the central part of Northeast China. Environmental potential of sustainable urbanization is the main contributor to sustainable urbanization potential in Northeast China. There is no absolute relationship between city size and potential value, large city does not always mean greater potential. Correlation analysis shows that urbanization rate cannot reflect the sustainable urbanization potential of a region. Population urbanization is not the ultimate goal of sustainable urbanization. Unilateral pursue urbanization rate cannot improve the potential of sustainable urbanization. Towards sustainable urbanization, governments in Northeast China should revitalize local economy, pay more attention to the rural areas and develop low-carbon economy or ecological economy. Finally, this paper highlights the importance of choosing more integrated methodology or new models for measuring sustainable urbanization potential in view of the shortcomings of one method.  相似文献   

15.
城市土地的高效利用是城市高质量发展的关键因素之一,特别是对于土地资源相对稀缺的大型城市。以国家中心城市建设对象郑州市为例,通过构建土地利用效益系统分析框架与城市土地利用转移矩阵,本文揭示了快速扩张型城市的土地利用效益系统演化规律、子系统间的动态耦合协调关系以及土地利用类型之间的转换逻辑。研究发现:郑州市土地利用效益系统逐步从生态环境效益偏好型(1998–2005年)向社会经济效益偏好型(2006–2019年)进行转变,并呈现典型的“倒U型”演化特征。伴随这一演化过程,郑州市的城市空间快速增长了461 km2。土地利用转移矩阵的分析显示,郑州市土地利用类型转换幅度最大的是草地、耕地、林地以及水域等土地利用/覆被类型,其在22年间不断转换为城市建设用地,并成为郑州市城市空间快速扩张的主要原因。地方政府应当根据城市土地利用效益系统特征和子系统间耦合协调关系演化态势,主动实施差异化的城市土地利用策略,同时积极把握城市增长边界划定契机,持续推进城市发展转型升级和生态城市建设。  相似文献   

16.
Numerous domestic scholars have argued that a remote location is the major factor preventing the transformation and sustainable development of resource-exhausted cities. Research to date, however, has not presented relevant evidence to support this hypothesis or explained how to identify the concept of ‘remoteness'. Resource-exhausted cities designated by the State Council of China were examined in this study alongside the provincial capital cities that contain such entities and three regional central cities that are closely connected to this phenomenon: Beijing, Shanghai, and Guangzhou. Spatial and temporal distances are used to calculate and evaluate the location remoteness degrees(LRDs) of resource-exhausted cities, in terms of both resource types and regions. The results indicate that resource-exhausted cities are indeed remote from the overall samples. Based on spatial distances, the LRDs are α_1 = 1.36(i.e., distance to provincial capital city) and β_1 = 1.14(i.e., distance to regional central city), but when based on temporal distances, α_2 = 2.02(i.e., distance to provincial capital city) and β_2 = 1.44(i.e., distance to regional central city). Clear differences are found in the LRDs between different regions and resource types, with those in western China and forest industrial cities the most obviously remote. Finally, the numbers of very remote resource-exhausted cities based on spatial and temporal distances(i.e.,α 1.5 ∩β 1.5) are 14 and 19, respectively, encompassing 17.9% and 24.4% of the total sampled. Similarly, 25 and 30 not remote resource-exhausted cities based on spatial and temporal distances(i.e.,α≤1.0 ∩β≤ 1.0) encompass 32.1% and 38.5% of the total, respectively. This study provided supporting information for the future development and policy making for resource-exhausted cities given different LRDs.  相似文献   

17.
城市中心人口减少以及城市面积向外部扩张严重影响了城市的自然生态环境,这是目前世界许多大城市如加拿大蒙特利尔面临的共同问题。限制城市向外部的扩展需要从城市中心的吸引力来平衡。本文采用数理统计和综合归纳方法,在蒙特利尔城市中心最受欢迎的社区之一Sainte-Marie进行了两次现场调查,以定量分析城市中心目前的吸引力。结果表明,目前本地住宅/服务业的中高档需求有所提高,对代表城市特征的一些变量进行相关性分析,认为人们在城市中心的吸引力和阻力的权衡中,不仅仅以"自由居住意志"为唯一选择依据,而是继续生活在Sainte-Marie。本文结论还认为,目前通过城市邻里的吸引力水平限制城市扩张仍然面临很大的挑战。  相似文献   

18.
揭示喀斯特城市流域土地利用对生态系统服务功能的影响机制,对喀斯特地区的社会经济发展与生态环境保护具有重要意义。本研究以贵州典型喀斯特城市流域—南明河流域为例,基于Arc GIS技术平台揭示了2000–2020年3个时期流域的土地利用时空演变规律,采用In VEST模型对流域不同土地利用类型的生态系统服务功能进行了系统评价。结果表明:(1)流域土地利用以林地、耕地和草地为主,土地利用变化方式主要表现为建设用地的增长,增长了13.07%;(2)流域水源涵养功能显著提升,碳储存功能略微减弱,空间上两者的物质量均呈现东北高、西南低的分布特征;(3)林地对流域水源涵养和碳储量的贡献率均超过57%,林地转为建设用地,耕地转为林地分别是生态系统服务功能减弱和增强的两种土地利用变化形式。本研究可为喀斯特生态脆弱区土地利用结构优化、水土资源开发和生态系统可持续管理提供重要数据支撑与科学参考。  相似文献   

19.
北京城市副中心(通州区)承接着北京中心城区的非首都核心功能,其快速建设发展亟需对区域内土地利用演变格局的科学认识。本文分析了改革开放40年来通州区土地利用演变格局,根据土地利用历史演变特征与城市发展规划目标,结合文旅发展驱动要素,运用FLUS模型模拟城镇化加速、减速和可持续发展3种情景下2035年北京城市副中心(通州区)土地利用空间分布格局。结果表明:(1)北京城市副中心(通州区)以城镇发展建设为主,1980—2010年高速城镇化阶段形成“沿六环顺运河”的城市扩张格局,2010—2020年低速城镇化阶段用地分布稳定,通州区形成从西北至东南城乡分异、土地集约化发展格局,副中心作为通州区城镇化的典型区域具有与通州整体相似的时空演变特征;(2)到2035年,3种情景间土地利用变化幅度和空间分布存在显著差异,城镇可持续发展情景下生态用地面积与分布最优,有利于实现城市可持续发展。在与三大副中心分区规划的契合程度分析中,可持续发展情景下预测模拟与市政府发布的《北京城市副中心控制性详细规划(街区层面)(2016—2035年)》(简称《规划》)用地高度契合,但文化旅游功能区和宜居生活风貌区中模拟预测与...  相似文献   

20.
The rapid progress of China's industrialization has been manifested in space as the formation and evolution of a series of industrial bases. Employing data from the years 1985, 2001 and 2010, this paper carries out differentiation, screening, and categorization of industrial bases in China. It then analyses the evolutional characteristics of these industrial bases and explores different paths of growth according to their scale or types, and summarizes the general pattern for their formation and evolution. The results of this study indicate that China's industrial bases as a whole have gone through three spatial stages since the founding of the PRC in 1949: decentralized development before reform and opening up in 1978, gradual concentration in eastern coastal regions during the early period of reform and opening up, and balanced and diversified development since the beginning of the 21 st century. By 2010, China had a total of 251 industrial bases and had thereby established the overall spatial map of its industrialization. As industrial bases expand in scale, their industrial structures develop from homogenization to diversification, and then again from diversification to competitive optimization. Leading industries in the vast majority of industrial bases constantly evolve along the track of light industries, basic materials industries, and advanced manufacturing industries. Meanwhile, the key factors in their evolution and development transition from traditional factors of production like resources and labor to new ones like capital and information, but there are significant differences in terms of influencing factors and growth paths between large, medium, and small bases. Small industrial bases primarily rely on natural resources to maintain development through a single leading industry, medium industrial bases gradually become more comprehensive in their industrial compositions, and large industrial bases evolve in the direction of a combination of basic materials industries and equipment manufacturing industries.  相似文献   

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