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1.
华北地区冬小麦干旱风险区划   总被引:11,自引:0,他引:11  
灾害风险评估与区划是是实现灾害应急管理向风险管理转变的关键。综合考虑了影响灾害风险大小的自然属性和社会属性,从多角度选取了干旱灾害强度、基于冬小麦干旱指数的干旱频率、基于灾损的干旱频率、灾年减产率变异系数、区域农业经济发展水平、抗灾性能指数等6个风险评估指标。通过引入CCA排序方法,揭示了不同风险评估指标之间的相关关系以及评估指标与相对气象产量的关系;并以确定的风险评估指标和相对气象产量之间的关系为基础,构建了不考虑抗灾和考虑抗灾2种风险指数。对比两种风险指数分析结果,表明在抗灾和不抗灾2种条件下,华北地区冬小麦干旱风险格局发生了明显改变。说明在当前农业生产水平下,人类的减灾抗灾和风险管理水平对冬小麦生产起着至关重要的作用。最后,以模糊聚类分析为手段,以考虑抗灾能力的风险指数和灾年减产率为分类标准进行聚类,实现了华北地区冬小麦干旱风险综合区划。  相似文献   

2.
乌日娜  张兴东  曹永强  王妍 《生态学报》2022,42(16):6731-6744
以辽宁省气象数据、空间数据和田间管理数据集为基础,首先,依据自然灾害风险形成理论,从危险性、脆弱性、暴露性和防灾减灾能力四因子入手,选择10个副指标,构建辽宁省玉米旱灾综合风险评价指标体系,并利用组合加权法和GIS空间分析方法,确定其权重及区域化。利用自然灾害风险指数法和加权综合评价方法,建立辽宁省玉米旱灾综合风险评价模型,并进行了辽宁省玉米旱灾时空分布特征分析及综合风险评价研究。结果表明:(1)自1960年以来,研究区干旱频率总体呈上升趋势,尤其2010年以后有明显增加态势。其中1970-1979年间干旱发生频率较低,2010-2019年间干旱频率最高。不管是月尺度、季节尺度、生长季尺度还是年际尺度,辽宁省西北部干旱频率普遍较高,而东南部干旱频率较低。干旱强度呈现从辽宁省中部地区向东西地区两个方向递减的趋势,高值出现在辽宁省中部的阜新、锦州、铁岭、辽阳、盘锦、鞍山、营口和大连等地。干旱历时从辽宁省东部向西部区域递减的趋势,其中高值出现在铁岭北部、盘锦、鞍山、营口和丹东南部等地,低值分布在朝阳西南部、葫芦岛西北部、本溪西部和丹东等地。(2)从4个因子角度来说,辽宁省朝阳西部和葫芦岛西北部玉米旱灾危险性指数较低以外其他区域玉米旱灾危险性指数均较高。然而,辽宁省西北玉米主产区玉米旱灾脆弱性指数和暴露性指数均较高,且防灾减灾能力较低。当4个因子加权综合评价时,辽宁省西北部玉米旱灾综合风险呈现较高的现象。研究结果可为保障辽宁省粮食安全及制定防灾减灾政策提供理论依据和科学指导。  相似文献   

3.
薛昌颖  张弘  刘荣花 《生态学杂志》2016,27(5):1521-1529
干旱是对农业影响最大的农业气象灾害,进行干旱风险评估对于提升区域灾害风险管理和决策水平、减轻农业损失具有重要的指导意义.本文基于自然灾害风险理论,利用黄淮海夏玉米主产区69个站点的气象、夏玉米播种面积和产量数据,以及当地有效灌溉面积等数据,从灾害风险的危险性、脆弱性、暴露性和防灾减灾能力4个方面构建风险评估指标和模型,对黄淮海夏玉米主产区干旱灾害的风险进行评估分析.结果表明: 黄淮海地区夏玉米生长季(6—9月),干旱发生危险性最大的阶段主要是播种-出苗期和乳熟-成熟期,其中,河北中南部、河南西部和北部的危险性最大.经加权叠加脆弱性、暴露性和防灾减灾能力后,夏玉米干旱综合风险最大的地区主要分布在河南西部和西南部部分地区;其次是河南南部、河北沧州、邢台以及山东德州等地,属于次高风险区;风险低值区主要分布在山东南部、安徽北部和河南的信阳等地;其他地区属于中度风险区.  相似文献   

4.
中国南方干旱灾害风险特征及其防控对策   总被引:6,自引:0,他引:6  
应用中国南方区域14省区市252个国家基本气象站1961—2015年逐日地面气象观测资料及干旱灾害资料,研究中国南方干旱灾害影响的时空变化特征,分析中国南方干旱灾害风险变化特征,提出干旱灾害风险防控策略与防御对策。结果表明:近55年中国南方区域降水量呈现波动变化,降水量线性拟合趋势特征不明显。但进入21世纪后南方区域平均降水量明显偏少,且平均降水量年际振荡幅度增大。近55年研究区气温呈显著上升趋势,南方平均地表气温升高速率高于全球地表升温速率;研究区气温从1976年开始持续上升,气温升高的突变年在1997年。重旱风险高发区主要集中于西南,随着气候变暖,干旱灾害频率、强度和受旱面积均增加,干旱灾害风险增大。气温突变后次高干旱灾害风险区明显扩大。未来10年(2016—2025年)中国南方地区的干旱发生频率可能升高。因此,要加强干旱灾害风险管理,生态环境脆弱区域实施生态环境修复,农业主产区域以保障粮食安全为主,解决水资源时空分布不均和资源供需加剧矛盾,提高干旱灾害风险防控水平。  相似文献   

5.
在干旱特征研究的基础上开展季节性干旱分类分区,可为不同干旱区域应对全球气候变化、制定抗旱减灾对策和防控技术提供理论依据.以国家标准中的气象干旱、农业干旱指标为主要依据,利用南方地区268个气象台站1959-2008年的气候资料,在分析南方地区季节性干旱的气候背景和分布特征的基础上,采用综合因子与主导因子相结合方法、逐级指标筛选法,综合灾害分析和聚类分析方法,对季节性干旱进行3级分区.一级分区以年干燥度和季干燥度为主要指标,以年尺度和主要作物生长季的降水量为辅助指标,将南方区域分为半干旱区、半湿润区、湿润区和极湿润区4个一级区;在此基础上再划分为川滇高原山地温凉半干旱区,江北温暖半湿润区、华南暖热半湿润区和西南高原温凉半湿润区3个半湿润区,长江流域温热湿润区、华南暖热湿润区和西南山地温暖湿润区3个湿润区,以及华南暖热极湿润区和江南西南山区温凉极湿润区2个极湿润区,共9个二级干旱分区.最后基于多个干旱指标的干旱频率和干旱强度,将南方区域分成29个三级干旱区.在分区基础上对不同季节性干旱特征分区分布情况、干旱特点及对农业生产影响进行评述,并提出了防旱避灾措施.  相似文献   

6.
中国旱灾风险定量评估   总被引:2,自引:0,他引:2  
全球变暖及经济社会快速发展导致区域及全球性灾害风险增大,中国更是几乎每年都会遭受旱灾,因此,开展旱灾风险评估及影响因素研究对于区域经济社会可持续发展和灾害风险管理具有重要意义。以前的旱灾风险评估在评估方法以及评估指标选取方面都具有很强的主观性,导致风险评估结果具有强烈的不确定性,这在划定我国的高旱灾风险区域时可能会造成问题。基于旱灾风险的定义,合理假设"历史上旱灾损失高的地区遭受高旱灾损失的概率越大",引入历史旱灾损失资料对旱灾风险进行校正,构建了新的旱灾风险评估模型,揭示了中国旱灾风险的区域分异规律,并量化了各个影响因子的贡献水平。分析结果表明,我国存在5个显著的旱灾高风险区:东北地区、华北地区、西北地区东部、西南地区东部以及西北地区西部的小部分区域。影响因子分析进一步表明,高暴露度和高脆弱性是导致地区出现高旱灾风险的主要原因。  相似文献   

7.
近57年来黄土高原干旱特征及其与大气环流的关系   总被引:2,自引:0,他引:2  
王佳瑞  孙从建  郑振婧  李晓明 《生态学报》2021,41(13):5340-5351
通过黄土高原地区52个气象站点1961-2017年的气象资料,利用不同尺度的标准化降水指数(Standardized Precipitation Index,SPI)和标准化降水蒸散指数(Standardized Precipitation Evapotranspiration Index,SPEI)对该区57年来干旱的时空变化特征进行了分析,并利用交叉小波变换探讨了干旱指标与大气环流的遥相关分析,得到了以下结论:(1)时间变化上,黄土高原57年来不同干旱指标均呈下降趋势,整体逐渐变干旱。但SPEI6指标较SPI6指标相比,干旱年份更多,干旱特征更明显,说明SPEI的计算由于考虑了蒸散发输入因此结果偏重.不同指标均显示,1999年以来,黄土高原地区干旱时有发生,但整体有降低的趋势。(2) SPEI6和SPI6的站次比和干旱强度最高点都出现在1999年,但SPEI6的站次比和干旱强度的变化幅度更剧烈,且出现全域性干旱的年份(5年)也多于SPI6(3年);SPEI12相较于SPI12,站次比和干旱强度较为相似,都在1966年达到顶峰,虽然出现全域性干旱的年份SPEI12(9年)多于SPI12(3年),但SPI12的干旱强度更高。(3)平原区的汾渭平原是轻旱多发区,河套平原、宁夏平原易发生中旱,同时宁夏平原还是重旱多发区。丘陵区西部的中宁、同心两地易发生重旱,乌审旗出现特旱。山地区干旱频率普遍较高,尤其是西部山地区的乌鞘岭重旱、特旱频发。(4) SPEI指数对环流指数的变化更敏感。AMO对区域各干旱指标的影响较小,ENSO、WPI对SPI6、SPEI6有显著的响应;而PNA对6个月尺度的干旱指标(SPI6、SPEI6)影响较小,对12个月尺度的干旱指标(SPI12、SPEI12)影响较大。区域干旱是一个复杂的自然现象,为了进一步探索不同干旱指标在不同区域的运用,必要时可采用多种指标,从不同角度比较多种干旱指标的相似性,从而避免单一指标对结果的局限性。  相似文献   

8.
A Fire Risk Index (FIRISK) based on an original land cover/land use nomenclature has been developed in the framework of EU-funded MEDALUS projects and integrated into a composite index of sensitivity to desertification (the so called environmentally sensitive area index: ESAI). The objective of the present study is to introduce a validation approach assessing the correlation between the FIRISK and seven independent fire indicators and quantifying the similarity in their spatial distribution in a study area (Attica, Greece) characterized by high fire risk and fragmented land-use structure. The FIRISK correlated positively with four out of seven fire indicators (average fire size, percentage of burnt area on the total municipal area, percentage of cropland and pastures burnt in each fire) in a non-linear fashion. Cluster analysis indicates that FIRISK spatial distribution was coherent with variables describing both fire size and the use of land endangered by fire. Results of the present study demonstrate that the FIRISK is a reliable indicator of fire risk within the ESAI framework. Moreover, the index is considered a key component of multi-criteria decision support systems classifying land according to the level of fire sensitivity.  相似文献   

9.
The article describes how economic resilience of farming households can be measured using a composite indicator of revealed adaptive actions, and investigates how capabilities of farm households to recombine human, financial, natural and physical capitals are linked to observed economic resilience to land set-aside interventions. The land set-aside intervention known as the Grain for Green Project (GGP), which has been altering livelihoods of farming households in China’s Loess Hills since 1999, is taken as a case study. Household surveys were conducted in three V-shaped valleys and three riparian areas in Yanhe Township in northwestern China in an effort to measure household resilience and explore its’ relationship to forms of capital. A composite index of adaptive strategies that can reorganize livelihood activities under land set-aside intervention into a new economic equilibrium is crafted using an objective weighting scheme based on principal component analysis. Subsequently, a multiple regression model was utilized to examine the relationship between the composite resilience index and various indicators related to human, social, financial, natural and physical capitals. The results reveal the latent structure and internal correlations of adaptive strategies, and present quantitative evidence about the relationship between livelihood capitals and household economic resilience. The analysis shows that household resilience deteriorates when the ratio of GGP land to cultivated farmland goes above a threshold level, and revealed that interventions targeting various forms of capitals can enhance the economic resilience for households to conservation efforts.  相似文献   

10.
基于PSR模型的国家公园综合灾害风险评估指标体系构建   总被引:2,自引:0,他引:2  
灾害会对社会-生态系统产生严重影响,造成重大的社会、经济、环境等方面的损失,科学地对灾害风险进行评估是进行防灾减灾的基础工作。自然保护地是区域灾害风险管理热点地区,在国家公园体制试点建设与自然保护地体系改革中,国家公园作为保护重要生态系统并保障全民公益性的重要的自然保护地类型之一,管理目标的多样性,决定了其具有多风险源-多受体的灾害风险特征,因此,进行全面有效的灾害风险评估是支持国家公园生态系统管理、游客管理、社区管理等具体管理目标的必要环节。在明确国家公园灾害风险的特征与内涵的基础上,以国际减灾署灾害风险定量评估框架为依据,细分灾害风险源和风险受体,然后针对国家公园不同类型的灾害风险受体,以灾害风险源的危险性与灾害风险受体的脆弱性(包含敏感性、暴露性和适应性)衡量灾害风险度,结合压力-状态-响应(Pressure-State-Response, PSR)模型,构建了适用于国家公园综合灾害风险管理的评估指标体系,旨在为国家公园的灾害风险管理提供理论基础和科学依据,服务于国家公园多元化管理目标。  相似文献   

11.
太湖流域生态风险评价   总被引:12,自引:12,他引:12  
许妍  高俊峰  郭建科 《生态学报》2013,33(9):2896-2906
随着城镇的急剧扩张和经济的快速增长,流域生态环境遭到极大冲击和破坏,致使生态系统出现资源退化、环境恶化与灾害风险加剧的趋势,生态环境面临前所未有的挑战.从复合生态系统入手,深入分析流域内各生态系统要素之间的相互作用与影响机制,综合考虑多风险源、多风险受体和生态终点共存情况下的风险大小,从风险源危险度、生境脆弱度及受体损失度三方面构建了流域生态风险评价技术体系,并选取太湖流域为实证区域,对太湖流域2000年、2008年两个时期生态风险的时空演化特征进行评价与分析.结果表明:太湖流域生态风险指数介于0.015-0.253之间,以中等和较低生态风险为主.至2008年,高、较高生态风险所占面积逐渐扩大,已由2000年的5.66%、13.42%增加至6.05%、18.42%,主要集中在流域北部的常州市区、江阴市大部分地区以及无锡市区.  相似文献   

12.
李志慧  张玥  彭璐  吴锋 《生态学报》2023,43(2):625-638
“一带一路”沿线部分国家处于生态环境脆弱、社会经济落后状态,开展社会经济-生态复合系统恢复力时空特征评估及关键要素识,对于实现“一带一路”倡议“走出去”战略和绿色丝路建设至关重要。基于社会发展、经济水平、基础设施建设、生态环境、自然灾害风险5个一级指标24个二级指标构建了社会经济-生态复合系统恢复力评价指标体系,利用主成分分析法和结构方程模型评价了2000—2015年尼泊尔县域尺度社会经济-生态复合系统恢复力并分析了其时空分异特征,厘清了影响社会经济-生态复合系统恢复力的关键因素及其影响机制。结果表明:(1)尼泊尔社会经济-生态复合系统恢复力在县域尺度上主要集中在中低和中等恢复力水平,而中高恢复力呈由南向北逐渐降低态势,南部地区以及位于中部发展区的首都加德满都河谷地区恢复力水平相对较高;(2)2000—2015年尼泊尔社会经济-生态复合系统恢复力在不同阶段呈现波动变化状态,2005年恢复力最优,2010和2015年部分区域恢复力降低明显,系统恢复力区域间差异逐步增大;(3)社会发展、经济水平、基础设施、建设生态环境和自然灾害风险对系统恢复力提升的总效应分别为0.99,0.07,0.11...  相似文献   

13.
1961-2017年环渤海地区气象干旱时空特征及致灾危险性评估   总被引:1,自引:0,他引:1  
王晓利  张春艳  侯西勇 《生态学报》2019,39(13):4647-4659
基于1961-2017年环渤海地区60个地面气象站点的逐日气温和降水资料,计算了各站点逐日气象干旱综合指数(Meteorological drought Composite Index,MCI),统计近57年各站点的气象干旱过程,并进一步分析了环渤海地区各季节气象干旱的时空变化特征及致灾危险性等级分布。结果表明:(1)环渤海地区春季干旱覆盖范围和持续日数呈下降趋势,但干旱强度有所增加,夏、秋两季干旱覆盖范围和持续日数呈上升趋势,而干旱强度有所减少,冬季干旱覆盖范围和干旱强度均呈增加状态,干旱持续日数有所下降。(2)春季干旱覆盖范围、干旱持续日数、干旱强度以及干旱发生频率均居四季之首,干旱状况最严重,夏、秋季次之,冬季最轻。(3)各季节干旱强度和干旱发生频率的高值区主要分布在辽宁西北部、河北中南部以及山东大部分地区,低值区主要位于辽宁东部地区。(4)各季节干旱致灾危险性等级总体呈西高东低、南高北低的分布特征,其中,河北中南部气象干旱的致灾危险性较高,辽宁东部的较低;春旱致灾危险性总体较高,夏、秋季次之,冬季最低。  相似文献   

14.
定量评价和比较四川盆区移栽水稻与直播水稻各发育阶段及全生育期干旱灾害风险,能为各区域水稻防旱减灾生产技术转型和推广提供科学依据.基于自然灾害风险理论和水稻干旱灾害风险形成机理,利用四川盆区1961—2017年的气象资料、水稻生产观测资料、农业统计资料和基础地理信息,对移栽和直播水稻全生育期和播种-拔节、拔节-孕穗、孕穗-齐穗、齐穗-成熟4个发育阶段干旱危险性进行评价和比较,对四川盆区水稻干旱灾害承灾体易损性、成灾环境敏感性和防灾减灾能力进行分析,从而构建四川盆区水稻干旱风险评价模型,并对评价结果进行区划.结果表明: 四川盆区水稻旱灾风险整体较高,两种播栽方式下均为中等风险区分布面积最广;两种播栽方式下干旱风险空间分布特征总体一致,表现为中东部高、西南部低,从东向西、从中部向周围递减的趋势.两种播栽方式下,水稻干旱危险性差异最大的时期出现在播种-拔节阶段,直播水稻在播种-拔节阶段的干旱危险性明显低于移栽水稻,且分布范围也较移栽水稻小;直播水稻干旱灾害的轻-低风险区分布较移栽水稻广,高风险区分布面积较移栽水稻略小.  相似文献   

15.
The threat of damage to buildings and other infrastructures resulting from land subsidence associated with groundwater pumping in urbanized areas is an ongoing problem requiring assessment. An important goal of subsidence vulnerability assessment is to construct a composite subsidence vulnerability index (SVI) that is represented by a set of indicators that focuses on four different thematic factors: physical, social, economic, and environmental vulnerability. These indicators are evaluated on the basis of indicator selection principles and then weighted by their contribution rate to the overall index. The weights reflect different measures assigned to the township-specific conditions. A complete and composite subsidence vulnerability assessment is developed in which future vulnerability management decision-making processes can be readily made. The vulnerability assessment includes not only the construction of the SVI, which involves selecting, assigning value to, weighting, and aggregating the vulnerability indicators, but also the presentation of the SVI decomposition. Research results demonstrate that a composite subsidence vulnerability assessment method can be made by first constructing and then decomposition-presenting the overall SVI. This allows for the relative comparison of subsidence vulnerability and the identification of the main vulnerable indicators; thus providing subsidence risk, which represents an important step toward vulnerability management of water resources.  相似文献   

16.
何斌  王全九  吴迪  周蓓蓓 《生态学杂志》2016,27(10):3299-3306
随着气候变化,农业干旱直接威胁粮食安全.本文以陕西省为研究对象,基于自然灾害风险理论,综合考虑干旱灾害影响因素,从致灾因子的危险性、承灾体的暴露性、环境的脆弱性和地区的抗旱能力4个风险要素选取指标,采用层次分析法确定指标权重,构建自然灾害风险综合指标,分析2009—2013年陕西省农业干旱时空特征.结果表明: 研究期间,陕北地区农业干旱风险略呈下降趋势;陕南地区呈急剧升高态势,以商洛市为甚;关中地区基本稳定,以咸阳市最高、西安市最低.陕西省农业干旱风险大体呈现从南向北逐渐递增现象.  相似文献   

17.
侯丽丽  都瓦拉  银山  玉山 《生态学报》2022,42(3):1059-1070
草原火灾给牧区人民生命财产及牧区生境带来了严重的威胁。以牧区村落汗敖包嘎查为例,从牧户微观尺度出发,基于实地调查获取的牧民社会经济数据,并结合气象和遥感数据,运用自然灾害风险指数法、主成分分析法和加权综合法构建了汗敖包嘎查草原火灾风险评价指标体系,获取了汗敖包嘎查草原火灾风险分布图。结果表明:汗敖包嘎查草原火灾风险从中部地区向四周递减,西北部地区风险高于东部、南部地区,中、高风险区占研究区总面积的49.85%。研究结果从微观尺度为草原火灾风险评价提供了新的视角和参考。  相似文献   

18.
Studies on fate and toxicity are important aspects in environmental impact assessments of chemicals. In order to elucidate “what is worst” a ranking of the chemicals under investigation is of significant interest, which obviously constitutes a multi-indicator system (MIS). Partial order methodologies turn out to be advantageous tools for analyses of such systems.In the present paper we focus on QSAR generated fate and toxicity indicators of 30 chemicals, comprising of a variety of chemical structures. In many risk assessment studies the level of a multi-indicator system is abandoned and the data are aggregated in order to obtain a composite index. However, such aggregation techniques are far from being trivial. The present paper describes an alternative strategy to handle MIS, i.e., applying partial order methodology leading to useful information. The paper demonstrate how partial order techniques lead to a weak order of the 30 chemicals as well as to the relative importance of the single indicators included in the study. Specifically, the paper addresses the topics on the “relations between the indicators” and “do chemical structures constitute a valid basis for ranking chemicals according to their environmental impact?”.  相似文献   

19.
The present study aims to promote a methodological scheme to combine the main environmental pressures that can be attributed to tourism activity in order to characterize environmental sustainability for a defined area of concentrated tourism (DACT). The methodological framework is demonstrated in the prevalent tourism destination of Northern Greece, Chalkidiki. The approach puts forward the tourism environmental composite indicator (TECI) which is analytically defined, mathematically formulated and finally implemented for the case under study. TECI provides the basis for a comparative analysis for typical all-sized hotel categories in terms of their combined environmental pressure. Apart from energy and water consumption and waste generation, the presented scheme establishes links with life cycle assessment (LCA) in order to include estimations of carbon footprint (CO2-eq) for hotels’ accommodation and transport, embedded in the TECI concept. A questionnaire for hoteliers was designed for the above purposes, and was used as input, among other data, to the overall methodological approach. The hotel managers gave their feedback via a face-to-face interview. Different normalized key performance indicators, i.e., pressure per m2, pressure per room, pressure per guest night are combined in one single composite indicator. The relative significance of each environmental pressure considered is realized by embedding weighting factors in the TECI mathematical formulation. To demonstrate the methodology TECI provides a comparative analysis for typical all-sized hotel categories in Chalkidiki and concludes with characterizing the level of the environmental sustainability as very poor. The results provide a rich insight into the trade-offs/synergies between the main environmental pressures that can be attributed to tourism activity. The work presented adds up to the low number of respective implementations found in the literature, especially by combining the theoretical background of environmental indicators with LCA. Last but not least, the identification of environmental degradation “hot spots” is realized in order to provide insights for sustainable tourism practices to stakeholders of the tourism industry and highlight insights for strategic governance and policy modeling for the area under consideration.  相似文献   

20.
An asbestos management index (AMI) that reflects the risks to residential health and physical damage to asbestos-containing buildings, and suggests an optimal risk communication methodology through recognition test results obtained from residents sharing common buildings, was developed for this study. The test was followed by a management class evaluation and was executed by applying the developed index to a large number of public buildings. The AMI assessed the physical state of 23 public buildings containing asbestos and the associated health risks. One target building that made up 4.4% of the target area was evaluated as grade 3 (high risk); 10 buildings in another location, or 43.5% of the study area, were evaluated as grade 2 (moderate risk); and 12 buildings, or 52.1%, were evaluated as grade 1 (low risk). It is important that information be exchanged between the affected parties in relation to asbestos. In an effort to be socially just, there have been many efforts to continue research pertaining to communication development regarding asbestos risk.  相似文献   

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