基于河湖水系连通的流域水系健康评价新思路（英文）

河湖水系连通作为新时代国家治水方略被提出,成为科学界的一个研究焦点。通过河湖连通关系的类型、"量质交换"、诸动态"流"和生态功能的讨论,提出基于河湖连通关系的河流健康评价的一个新思路。认为在健康的河湖连通系统中,河湖之间存在着良性的"量质交换",它是河湖之间最基本的物质和能量交换关系;河湖之间的物质流(水、溶解物质、泥沙、生物,污染物等)、能量流(水位、流量、流速等)、信息流(随水流、生物和人类活动而产生的信息流动等)和价值流(航运、发电、饮用和灌溉等)畅通无阻;诸种"流"在自然和人类活动的影响下,以河湖水系连通为纽带,进行河湖之间的"量质交换",实现河湖相互作用;"量质交换"是河湖连通关系演变的途径和动力源泉;良性的河湖连通关系演化最终趋于相对稳定状态,即动态平衡。     

人类活动对河湖水系连通的影响评估

河湖水系承载着人类赖以生存的水资源,也支撑着经济社会的可持续发展。在自然因素和人类活动双重影响下,河湖水系不断发生着改变,也影响着人类生存和发展。特别是在人类活动日益剧烈的背景下,研究人类活动对河湖水系连通的影响是一个非常重要的科研问题,也是河湖水系连通工程实践的一个关键问题。本文从自然和人工两个方面分析了河湖水系连通的影响因素,阐述了人类活动对河湖水系连通的影响过程,并从河湖水系连通关系、河湖水系功能（自然角度）、河湖水系连通功能（社会角度）三个方面归纳了人类活动的正负面影响;在此基础上,提出了有针对性的影响量化评估方法,便于宏观角度量化和分析人类活动对河湖水系连通的影响。本研究以人类活动剧烈的淮河流域为实例应用,分析了人类活动对淮河水系的影响评价结果。     

西部山区农户生计资产综合评价——以遵义市为例（英文）

作为农户生计结构基础的生计资产状况是其拥有选择机会、采用生计策略和抵御生计风险的基础,也是获得积极生计成果的必要条件。准确量化农户生计资产可以从本源上对农户未来发展态势进行识别,对掌握农户的生计脆弱性、生计策略以及了解农户的生计现状都具有重要意义。本研究以地处西部山区的遵义市为研究区,釆用分层抽样方法与参与式农村调查评估法收集农户的生计资产属性和生计策略等相关数据,构建了农户生计资产指标评价体系,对不同生计策略类型农户的生计资产特征进行了评价分析。研究结果表明:(1)不同生计策略农户的生计资产总值差异较小,主要是因为不同类型生计资产的拥有结构上差异较大。(2)纯农户拥有较多的自然资产和物质资产,但其人力资产、金融资产和社会资产较匮乏。(3)非农户和兼业户拥有较多的人力资产、金融资产和社会资产,但拥有的自然资产和物质资产较匮乏。     

城市气候承载力定量化评价——以上海市为例（英文）

为了开展气候风险管理,近期学者们提出了气候承载力的概念。本文在分析气候承载力的概念内涵及其影响因子的基础上,从当前气候天然容量,城市气候压力和城市协调发展潜力3个方面构建城市气候承载力综合评价指标体系。以上海市为例,采用构建的城市气候承载力评价方法分析上海市2004-2013年气候承载力变化特点,并利用主成分因子分析法确定气候承载力的主要影响因子。分析结果如下:(1)当前气候天然容量指数表明上海市的气候条件劣于基准年,在研究期间呈波动状态;(2)城市气候压力和城市协调发展能力呈稳步增长状态,但协调发展能力的增长速度低于城市气候压力的增长速度;(3)总体来说,研究期间上海市气候承载力远低于基准年,且气候承载力值因受气候条件变化影响较大而处于较大波动状态;(4)基于主成分因子分析方法确定城市人口密度、人均GDP、单位生产总值能耗、工业总产值、环境保护投资、科技经费支出以及人均绿地面积为主要影响因子。结果表明,该气候承载力评价方法是可行的,它可以描述某一城市气候承载力在时域上的变化,也可以对区域气候承载力开发利用过程中存在的问题进行甄别,并可作为气候预警响应的依据,为我国建立气候安全管理机制提供技术参考。     

石油资源流动框架构建——以中国为例（英文）

石油作为现代工业社会的血液和全球性重要的战略资源,被广泛用于交通运输、化工、医药、制造等各行各业。加强石油资源流动研究,有助于理解石油在产业内部以及其他产业之间的流动过程。石油资源流动分析框架及测算方法研究是开展石油供需研究的基础与前提,同时也是石油产品二氧化碳排放评估研究的基础。鉴于此,本文构建了石油资源流动分析框架,把石油资源产业流动过程划分为4阶段,3种流,3种库和2个过程,归纳总结了石油资源流动测算分析方法。以中国为例开展实证研究,研究结果显示:(1)过去二十年中国石油生产、消费和出口量迅猛增长,快速正价的需求和有限的供应能力导致中国石油进口来源呈现多元化,从而实现国家层面上的石油安全;(2)终端消费掉多数石油产品,应该特别关注石油炼制过程中的损失情况;(3)除去原油,不同部门之间的石油产品流入量已经发展了巨大变化,在交通运输和生活消费部门呈现明显的上升趋势,而工业消费量呈现下降趋势。(4)石油资源流动的CO2排放而言,从1993年的4.56亿t上升到2013年的15.17亿t;与此同时,二氧化碳排放的前三名从工业、运输业(包括运输业、仓储和邮政业)、火力发电业转变为交通运输、工业和生活消费。此外,石油资源产业流动需进一步加强系统边界、数据库和针对非能源消费的石油资源流动模型研究等。     

贫困地区荒山土地整治的综合效应研究——以河北省阜平县为例（英文）

Land is the root of rural revitalization, and its core is to reinvigorate land resources through the building up of land capacity. Since the late 1990s, land consolidation efforts have been widely extended to all parts of China. Land consolidation has served as an essential instrument for reinvigorating stock land, strengthening intensive land use, timely supplementing cultivated land, and promoting agricultural modernization, as well as urban-rural integration. This study uses a typical poor village(Dadao Village) in a state-designated impoverished county(Fuping County, Hebei Province), to analyze the socioeconomic benefits and eco-environmental impacts of land consolidation. With the aid of first-hand data from questionnaire surveys, face-to-face interviews and the visual interpretation of land use and land cover changes(LUCC), we found that: 1) the barren hilly land consolidation(BHLC)helps to promote the transformation of resource-advantages into asset-advantages in poverty-stricken areas. In 2017, 60.16% households in the study area gained the additional transferred-income with an annual average of 2843 yuan, while 19.11% households received the wage-income with an annual average of 9871 yuan. 2) Land consolidation inspires farmers' enthusiasm to participate in village government and helps alleviate rural poverty. From 2014 to 2017, land consolidation has helped 585 poor in the village out of poverty. Meanwhile,by land consolidation, most farmers' attitudes towards land consolidation have shifted from"not caring" to "have great concern," and their identity cognition has gradually changed from being bystanders to becoming decision makers and supervisors. 3) Further analysis demonstrated that land consolidation could not only increase the quantity and quality of arable land,but also have a certain impact on eco-environment. During 2014–2016, the BHLC in the study area transformed 242.12 ha unused barren hilly land and open forest land into well-facilitated arable land, and increased the average arable land by 0.19 ha per capita. Also, the index of land use intensity increased by 27.01% between 2014 and 2016. Farmers' perceptions of environmental awareness have confirmed that such high-intensity LUCC were significant enough to make two-side impacts on eco-environment. We appeal to establish a combined organization and encouragement mechanism of rural land consolidation, to take the full breadth and depth of farmers' participation into consideration, and to formulate more scientific and sustainable land consolidation planning. Also, we put forward some suggestions and notes for the implementation and promotion of BHLC model. These findings can provide beneficial references for those involved in policymaking and planning in the areas of land consolidation and poverty alleviation in China, as well as other developing countries around the world.     

农业文化遗产保护的生态效益评估——以青田稻鱼共生系统为例（英文）

为了解和掌握全球重要农业文化遗产(GIAHS)项目实施10年来,青田稻鱼共生系统的生物多样性、生态系统结构与功能、生态环境等发展状况及其变化趋势,本研究通过历史资料收集、样地调查等方式,收集整理遗产地2005–2013年相关数据,开展了农业文化遗产保护的生态效益评估。结果表明:(1)GIAHS项目实施,遗产地传统水稻品种基本保持稳定,其它农作物种类基本保持不变,果树和药用植物品种发展较快。随着遗产地生态环境日益改善,系统内的生物多样性种类和丰富程度都有所增加,最具代表性的就是白鹭和野猪的不断增多。(2)青田县方山乡河流、森林、城镇和荒地生态系统面积增加,其中城镇生态系统增加面积最大,达到20.30 ha,森林生态系统面积增加了7.29 ha;湿地、水库、农田和草地生态系统面积减少,其中草地生态系统面积减少最大,达到28.87 ha。从不同生态系统类型服务功能价值变化来看,森林生态系统服务功能价值增加最多,达到9.20万元/年,河流和荒漠生态系统服务功能价值有所增加,但并不明显。(3)稻田土壤养分、稻田水质没有明显变化,稻田病虫害没有明显增加,各项监测指标远远好于标准值。农村改路、改水、改厕和村庄绿化、亮化和美化,极大改善了农村生产生活条件和农民居住环境。     

海岸带空间功能分区与管治方法研究——以宁波市为例（英文）

Reasonable development and utilization of spatial resources in the coastal zone not only affects the development quality of the marine economy but also impacts the utilization efficiency of spatial resources,playing an important role in regional sustainable development.Depending on the natural,economic,and societal characteristics of a region,research topics such as using relevant methods to divide the coastline,proper spatial development of the coast,protecting coastal zones,and achieving higher spatial resource distribution efficiency have recently become hot topics in geographic research.Most of the scholars construct the evaluation index system from the perspective of economic and ecological factors and undertake some exploration of the division methods.However,the selection of indicators for a coastal zone needs a different and more scientific approach.There is a need for emphasizing the overall strategy of land-ocean integration in developing spatial resources in a coastal zone.Taking the coastal zone in Ningbo as an example,this paper develops a new evaluation framework and spatial function regionalization method that is used to divide the coastline and coastal zone.Based on the perspective of overall strategy for the land and ocean,we evaluate the suitability of coastline development.We then propose the spatial function regionalization of the coastal zone.Finally,based on the status quo of spatial development in Ningbo,we divide the coastal zone into ecological space,production space and living space,and propose adjustment directions and control requirements for the different types of spatial layouts.     

旅游城市餐饮业空间布局特征——以拉萨市为例（英文）

受城市功能定位、旅游消费驱动等因素影响,旅游城市餐饮产业空间布局具有其自身特征。通过对互联网电子地图POI数据的挖掘,并结合ArcGIS最近邻分析、标准差椭圆、核密度分析和缓冲区分析工具,本文分析了高原旅游城市拉萨市主城区餐饮业空间分布格局特征及其影响因素(基于道路交通、旅游资源和人口视角)。研究发现拉萨市主城区餐饮业空间分布总体呈现集聚特征,主要集中在交通发达和旅游资源密集区周边地区;常住人口集聚区域餐饮点同样集中布局,餐饮点密集区与实时人口密集区高度重叠。针对拉萨市城市空间结构、功能定位和旅游发展,文章进一步提出拉萨市餐饮业空间布局优化措施。     

复杂地貌区域生态敏感区综合评价与保护对策——以钦州市为例（英文）

复杂地貌区域国土开发受生态环境因素影响较单一地貌地区更复杂,其境内生态敏感区类型较多,且空间分布比较杂乱,不同生态敏感区之间又相互影响。文章选择山、水、林、田、城互为镶嵌的广西钦州市作为案例城市,以小流域为评价单元,建立集"地"、"水"、"绿"三位于一体的评价体系,在遥感和GIS技术的支持下,将单因子定性分级和多因子空间叠加模型相结合,对整个区域的生态敏感区进行综合评价及分区。从研究结果来看,这种评价技术能够较好地反映这些生态敏感区的综合分异规律,有助于当地政府在区域开发中制定更为科学的生态安全防范对策。     

城市碳足迹与碳循环压力分析——以南京市为例（英文）

Urban carbon footprint reflects the impact and pressure of human activities on urban environment.Based on city level,this paper estimated carbon emissions and carbon footprint of Nanjing city,analyzed urban carbon footprint intensity and carbon cycle pressure and discussed the influencing factors of carbon footprint through LMDI decomposition model.The main conclusions are as follows:(1) The total carbon emissions of Nanjing increased rapidly since 2000,in which the carbon emission from the use of fossil energy was the largest.Meanwhile,carbon sinks of Nanjing presented a declining trend since 2000,which caused the decrease of carbon compensation rate and the increase of urban carbon cycle pressure.(2) The total carbon footprint of Nanjing increased rapidly since 2000,and the carbon deficit was more than ten times of total land areas of Nanjing in 2009,which means Nanjing confronted high carbon cycle pressure.(3) Generally,carbon footprint intensity of Nanjing was on decrease and the carbon footprint productivity was on increase.This indicated that energy utilization rate and carbon efficiency of Nanjing was improved since 2000,and the policy for energy conservation and emission reduction taken by Nanjing's government received better effects.(4) Economic development,population and industrial structure are promoting factors for the increase of carbon footprint of Nanjing,while the industrial carbon footprint intensity was inhibitory factor.(5) Several countermeasures should be taken to decrease urban carbon footprint and alleviate carbon cycle pressure,such as:improvement of the energy efficiency,industrial structure reconstruction,afforestation and environmental protection and land use control.Generally,transition to low-carbon economy is essential for Chinese cities to realize sustainable development in the future.     

农村宅基地功能转型分析——以江西省鄱阳县为例（英文）

农村宅基地是农村土地系统中极其重要的组成部分,是农村衰落、农村空心化等各种问题表征的重要载体。农村地区发生巨大变化的同时,农村宅基地也发生着深刻的转型。本研究在总结国内外对于农村宅基地多功能分类的基础上,根据实地调查问卷,从宅基地功能提升的角度划分并界定了宅基地的人口承载功能、资产以及居住功能。通过协调转型度模型对农村宅基地的功能及协调转型度进行了分析。结果表明:(1)2000–2017年鄱阳县农村宅基地功能转型度在整体上有了明显提升。(2)北部山地丘陵区及环鄱阳湖区主要分布着协调转型度的高值区,近县城的平原区主要分布着协调转型度的低值区。(3)区位条件与资源禀赋较好的区域,人口、资本等要素非农化的支撑条件也比较好,相应的非农化趋势也更为明显。应根据不同区域农村宅基地转型的差异化情况提出针对性的发展建议。     

喀斯特高原盆地聚落空间演变——以贵州省红枫湖水系盆地为例

贵州是我国喀斯特分布最广的地区,喀斯特高原盆地是贵州主要的人口聚集地。充分认识高原盆地聚落的空间分布及其演化态势,对区域城镇规划、社会主义新农村建设及可持续发展有重要意义。以红枫湖水系盆地为例,基于GIS技术及相关软件,主要利用景观格局指数、Moran’s I系数以及居民点数据与等高线数据的空间叠置及转换技术,从水平和垂直两个维度对案例地区聚落空间分布的变化进行研究。研究表明:喀斯特高原盆地聚落的空间分布和演变具有强烈的喀斯特地域基因,在喀斯特地貌的限制下聚落总体分布分散;近年来聚落规模不断增加,在局部有一定小规模集聚并随地形限制而表现出不同的集聚形式和集聚程度;而随着数量的增多和规模的增大,聚落形态更为复杂且景观趋于破碎,空间分布更加复杂;喀斯特地貌的垂直空间特点在决定聚落的垂直分布及演变规律的同时也加剧了聚落空间分布的复杂性。     

流域水资源利用的极化程度研究——以黄河流域为例（英文）

水资源过度利用对流域水资源实现可持续利用及生态环境具有很大的影响,量化水资源的开发利用程度对水资源合理利用具有重要的指导作用。基于此,本文提出了水资源利用极化概念旨在定性分析水资源利用是否存在超采;依据ER指数、TW指数以及方差的偏离度构建水资源利用极化指数模型,用来量化水资源利用的超采程度。并以黄河七个二级流域区为例,分别计算了地表水以及地下水资源可利用量、超采量、极化指数。结果显示:2012年黄河流域地表水资源可利用量为344.9亿m~3,占地表水资源总量的56.21%;地下水资源可利用量为58.4亿m~3,占地下水资源的58.74%。而且在黄河流域中下游水资源极化严重,其中黄河兰州至头道拐流域、龙门至三门峡流域段极化度最高,极化指数分别为:19.88、11.81。龙羊峡以上以及头道拐至龙门段不存在极化现象。总体而言,黄河流域水资源利用极化指数是7.95。水资源利用极化度的计算可为黄河流域水资源可持续利用提供重要的理论支撑。     

基于参数评估方法的不同灌溉方式的适宜性及其比较——以伊朗Khosouyeh Dam子流域为例（英文）

随着人口的急剧增加,人们对粮食和农产品的需求也会增加,与之相关联的农业土地利用问题也必然会越来越多,因此有必要研究土地的最大生产潜力——达到最大的生产能力而对农地不会产生不利影响,土地适宜性评估是实现这一目标的最重要方式。本研究的主要目的是基于参数评估方法对不同灌溉方法的优缺点进行评估与比较,以伊朗南部法尔斯省Khosouyeh Subbasin为例,该区域面积约为221402 ha。首先制备了土地单位图,选择了37个样本点,评估和分析其土壤性质,并采用GIS技术生成区域滴灌和漫灌的适宜性图。结果显示,对漫灌而言,98.42%的土地被归类为永久性不适合(N_2),1.52%目前不适合(N_1);对滴灌而言,77.73%的面积被归类为永久不适合(N_2),6.05%目前不适合(N_1),12.43%略适合(S_3)和3.79%适度适合(S_2)。滴灌和漫灌的限制因素都是土壤深度和土地坡度。     

地形因素对水稻生产的影响——以湖南省为例（英文）

Rice(Oryza sativa L.) is the most important staple crop of China, and its production is related to both natural condition and human activities. It is fundamental to comprehensively assess the influence of terrain conditions on rice production to ensure a steady increase in rice production. Although many studies have focused on the impact of one or several specific factors on crop production, few studies have investigated the direct influence of terrain conditions on rice production. Therefore, we selected Hunan Province, one of the major rice-producing areas in China, which exhibits complex terrain conditions, as our study area. Based on remote sensing data and statistical data, we applied spatial statistical analysis to explore the effects of terrain factors on rice production in terms of the following three aspects: the spatial patterns of paddy fields, the rice production process and the final yield. We found that 1) terrain has a significant impact on the spatial distribution of paddy fields at both the regional scale and the county scale; 2) terrain controls the distribution of temperature, sunlight and soil, and these three environmental factors consequently directly impact rice growth; 3) compared with the patterns of paddy fields and the rice production process, the influences of terrain factors on the rice yield are not as evident, with the exception of elevation; and 4) the spatial distribution of paddy fields mismatched that of production resources due to terrain factors. Our results strongly suggest that managers should scientifically guide farmers to choose suitable varieties and planting systems and allocate rice production resources in the northern plain regions to ensure food security.     

评估白蚁对牧场退化的影响:以埃塞俄比亚南部的Yabello为例（英文）

由于气候和人为因素的影响,白蚁对Yabello牧场的入侵率不断增加。本研究旨在评估白蚁对牧场的影响以及在研究区域可能的管理措施。本文根据白蚁传播的程度选择Yabello区(Dida Tuyura,Danbal-Waccu和Arero等三个kebeles)进行调研,采用田野调查方法,将半结构化问卷应用于40个社区代表中,每个选定的kebele共有120名社区代表参加了访谈,获得了直接观察和非正式讨论的相关数据,以了解白蚁对牧场退化的影响及其变化趋势。根据收集的数据,对研究区白蚁入侵率的历史背景进行了评估。除了评估白蚁对牧草产品、建筑物和农作物产生的直接影响外,本文还讨论了环境和管理机制的联系。总体来说,Yabello牧场一直处于白蚁侵袭压力之下并且以惊人的速度增加。因此,为了尽量降低白蚁对牧场退化的影响,建议结合当地社区知识和科学管理系统采取适当的评价技术。     

高校快递包装废弃物的现状及建议——以中国社会科学院研究生院为例（英文）

本文采用问卷调查和访谈的方式,对中国社会科学院研究生院快递包装废弃物的情况进行分析。调查结果表明:(1)校园吸纳了大量的快递包装,而且包装废弃物也非常多;(2)快递材料主要有纸包装,塑料袋,胶带和缓冲填料四种类型;(3)学生和学校在快递包装废弃物回收方面表现不佳;(4)本文研究的样本可以通过聚类分析分为四类,由此得出女大学生比例较高的大学应更加重视快递包装废弃物的回收问题。根据上述研究成果本文提出了一些建议:(1)建立校园垃圾回收系统是解决快递包装废弃物问题的最有效方法;(2)社会应该倡导绿色包装,从废物产生的源头进行管理,因为大多数快递包装材料不易自然降解,对人类健康和环境存在巨大的隐患;(3)学校应培养学生的环保意识。如果教育和惩罚结合实施,包装物回收制度将能更好的运行。     

中国人文地理综合区划的生成过程与方案（英文）

The comprehensive regionalization of Chinese human geography is based on the rules governing regional differentiation of Chinese physical geographic factors. Based on regional differences and similarities in human factors, this study divides the whole country into two levels of relatively independent, complete and organically linked human geographic units. As a fundamental, comprehensive, cutting-edge, practical and important task, the comprehensive regionalization of human geography highlights the characteristics, regional and sub-regional features, complexity and variety of spatial differences between factors of Chinese human geography. It is capable of promoting the development of human geography based on local conditions, providing basic scientific support to national and local development strategies, such as the Belt and Road Strategy, new urbanization and environmental awareness, and creating a sound geopolitical environment in key areas. Using results from existing physical and human geographic zoning studies, and in accordance with the principles of synthesis, dominant factors, the relative consistency of the natural environment, the relative consistency of social and economic development, the consistency of the regional cultural landscape, the continuity of spatial distribution and the integrity of county-level administrative divisions, and taking as its basis the division of human geography into 10 major factors(nature, economy, population, culture, ethnicity, agriculture, transportation, urbanization, the settlement landscape and administrative divisions), this paper constructs an index system for the comprehensive regionalization of Chinese human geography through a combination of top-down and bottom-up zoning and spatial clustering analysis. In this study, Chinese human geography is divided into eight regions and 66 sub-regions. The eight human geography regions are(Ⅰ) Northeast China,(Ⅱ) North China,(Ⅲ) East China,(Ⅳ) Central China,(Ⅴ) South China,(Ⅵ) Northwest China,(Ⅶ) Southwest China, and(Ⅷ) Qinghai and Tibet. This zoning proposal fills gaps in studies involving the non-comprehensive regionalization of Chinese human geography. Each human geography region and sub-region has different topographical, climatic, ecological, population, urbanization, economic development, settlement landscape, regional cultural and ethno-religious attributes. This proposal on the comprehensive regionalization of Chinese human geography dovetails closely with previous studies on comprehensive regionalization in Chinese physical geography, Chinese economic zoning, and Chinese agricultural zoning. It shows that, under the dual roles of nature and humans, there are certain rules of regional differentiation that govern the comprehensive regionalization of Chinese human geography.     

中国城市空气污染及其空间溢出效应评估——以113个环保重点城市为例（英文）

近年来,中国城市空气污染问题日益受到学界和民众的广泛关注。对城市空气质量进行科学评价并分析其相关影响因素,对于空气污染治理具有重要的理论和实践意义。中国自2013年初实施新的空气质量标准(GB 3095-2012),PM_(2.5),O_3,CO,PM_(10),SO_2,NO_2等六种污染物被列入监测指标,并由环保部信息发布平台公布污染物浓度数据。本文收集了中国113个环保重点城市2014、2015年六种污染物浓度数据,基于核密度分析法、空间热点分析法来刻画中国城市空气污染演变格局和集聚形势。通过熵值评价系统,构建了综合空气质量(CAQI)指标,并解析六种污染物对中国城市空气质量的综合影响。研究结果表明,大体上,CO和SO_2是中国大部分城市空气的主要污染物,但在不同类型城市表现出明显差异。空气质量较差的城市主要位于华北和华中地区,其中京津冀地区尤为严重。利用一般回归模型、空间滞后和空间误差回归模型探究影响城市空气质量的主要影响因素。结果表明气象条件和人类活动对城市空气质量影响显著,具体表现为工业化和城镇化因子与城市空气综合质量具有较高的相关性。空间滞后模型结果显示城市空气污染存在明显的空间溢出效应,表明临近城市之间的空气质量相互影响程度较高。因此,本研究建议政府和相关组织应加强区域联防联控和深度合作,共同治理城市空气污染问题。