Our understanding of when and how humans adapted to living on the Tibetan Plateau at altitudes above 2000 to 3000 meters has been constrained by a paucity of archaeological data. Here we report data sets from the northeastern Tibetan Plateau indicating that the first villages were established only by 5200 calendar years before the present (cal yr B.P.). Using these data, we tested the hypothesis that a novel agropastoral economy facilitated year-round living at higher altitudes since 3600 cal yr B.P. This successful subsistence strategy facilitated the adaptation of farmers-herders to the challenges of global temperature decline during the late Holocene. Copyright © 2015, American Association for the Advancement of Science.

Most intensive human activities occur in lowlands. However, sporadic reports indicate that human activities are expanding in some Asian highlands. Here we investigate the expansions of human activities in highlands and their effects over Asia from 2000 to 2020 by combining earth observation data and socioeconomic data. We find that ∼23% of human activity expansions occur in Asian highlands and ∼76% of these expansions in highlands comes from ecological lands, reaching 95% in Southeast Asia. The expansions of human activities in highlands intensify habitat fragmentation and result in large ecological costs in low and lower-middle income countries, and they also support Asian developments. We estimate that cultivated land net growth in the Asian highlands contributed approximately 54% in preventing the net loss of the total cultivated land. Moreover, the growth of highland artificial surfaces may provide living and working spaces for ∼40 million people. Our findings suggest that highland developments hold dual effects and provide new insight for regional sustainable developments.© 2022. The Author(s).

Many features of the environment have been found to exert an important influence on cardiovascular disease (CVD) risk, progression, and severity. Changes in the environment because of migration to different geographic locations, modifications in lifestyle choices, and shifts in social policies and cultural practices alter CVD risk, even in the absence of genetic changes. Nevertheless, the cumulative impact of the environment on CVD risk has been difficult to assess and the mechanisms by which some environment factors influence CVD remain obscure. Human environments are complex, and their natural, social, and personal domains are highly variable because of diversity in human ecosystems, evolutionary histories, social structures, and individual choices. Accumulating evidence supports the notion that ecological features such as the diurnal cycles of light and day, sunlight exposure, seasons, and geographic characteristics of the natural environment such as altitude, latitude, and greenspaces are important determinants of cardiovascular health and CVD risk. In highly developed societies, the influence of the natural environment is moderated by the physical characteristics of the social environments such as the built environment and pollution, as well as by socioeconomic status and social networks. These attributes of the social environment shape lifestyle choices that significantly modify CVD risk. An understanding of how different domains of the environment, individually and collectively, affect CVD risk could lead to a better appraisal of CVD and aid in the development of new preventive and therapeutic strategies to limit the increasingly high global burden of heart disease and stroke.© 2017 American Heart Association, Inc.

Globally, about 400 million people reside at terrestrial altitudes above 1500 m, and more than 100 million lowlanders visit mountainous areas above 2500 m annually. The interactions between the low barometric pressure and partial pressure of O, climate, individual genetic, lifestyle and socio-economic factors, as well as adaptation and acclimatization processes at high elevations are extremely complex. It is challenging to decipher the effects of these myriad factors on the cardiovascular health in high altitude residents, and even more so in those ascending to high altitudes with or without preexisting diseases. This review aims to interpret epidemiological observations in high-altitude populations; present and discuss cardiovascular responses to acute and subacute high-altitude exposure in general and more specifically in people with preexisting cardiovascular diseases; the relations between cardiovascular pathologies and neurodegenerative diseases at altitude; the effects of high-altitude exercise; and the putative cardioprotective mechanisms of hypobaric hypoxia.© 2021 Mallet et al.

Urbanization in the Qinghai-Tibet Plateau is a special mission in defending the national security, the national ecological security and the Asian Water Tower. It plays an irreplaceable role in the world, which ensures the realization of modernization, the happiness of all ethnic groups, a stronger ecological security and a more solid national security barrier in this region. This study discusses in detail the special driving force, development path, development goals, development pattern, green development mode and green development path of new urbanization in the Qinghai-Tibet Plateau, which are completely different from the inland areas. It is believed that the urbanization of the Qinghai-Tibet Plateau is a process characterized by low-level development, cultural inheritance, national defence, water tower protection, small agglomeration and large dispersion, social inclusion, and ecological enrichment. It is driven by a single investment, tourists, services, and counterpart support in an alpine and anoxic environment. In the future, the urbanization development thinking in the Qinghai-Tibet Plateau is, firstly, to take the defence of the territory and the border as the guideline to ensure national security, and a sufficient population in the border and rural areas at a fast, stable and appropriate growth rate. By 2035, the permanent population of the plateau will reach 16 million, and the urbanization rate should be 52.5%, which will be stable in the middle stage of urbanization for a long time, and the quality of urbanization will be promoted comprehensively. Secondly, driven by green development, the ability and level of ecological products and ecological services will be continuously improved, highlighting characteristics and folk customs, and promoting cultural diversity and inclusiveness. And we encourage local herdsmen to live in the town and graze in the township so that they can build beautiful cities and towns and advance in-situ urbanization on the plateau. Thirdly, based on the principle of small agglomeration and large dispersion, the pattern of borderland security urbanization is composed of "three circles, four belts and multi-nodes", emphasizing the agglomeration effect of the three circles (Xining metropolitan area, Lhasa metropolitan area, and Qaidam urban circle), four belts (urban belt along the Qinghai-Tibet Railway, urban belt along the Sichuan-Tibet Railway, town belt along the Tangbo Ancient Road, and border town zone), and multi-nodes (multiple important urban nodes, and important border towns). Fourthly, we should guarantee the channel development, including the construction of new infrastructure facilities such as the Qinghai-Tibet high-speed railway, and the building of plateau smart cities, so as to safeguard national security. Finally, taking territorial security as a top priority, we should speed up the reform of the land system in border cities, set up pilot special zones for borderland land reform, and focus on border cities in major national strategic layout and territorial spatial planning.

青藏高原城镇化肩负着捍卫国家安全屏障与护卫国家生态安全屏障及“亚洲水塔”的特殊使命,对守护好世界上最后一方净土、确保“地球第三极”同全国一道基本实现现代化、让青藏高原各族人民生活更幸福、使青藏高原生态安全屏障更牢固、使国家安全屏障更坚固都发挥着不可替代的重要作用。本文详细论述了青藏高原新型城镇化与内地截然不同的特殊驱动过程、特殊发展道路、特殊发展目标、特殊发展格局、绿色发展模式与路径,认为青藏高原城镇化是一个在高寒缺氧环境下,由单一投资拉动、游客带动、服务驱动、对口支援等特殊驱动形成的低度开发型、文化传承型、守土固边型、护卫水塔型、小聚大散型、社会包容型、生态富民型城镇化过程。未来发展思路是：以守土固边为先导,保障国家安全,快稳有度,确保边境和农村地区有足量人口,到2035年高原常住人口将达到1600万人,城镇化率宜为52.5%左右,将长期稳定在城镇化发展的中期阶段,全面提升城镇化发展质量;以绿色发展为主导,不断提高生态产品和生态服务能力及水平,突出特色,彰显民风,弘扬文化,住在镇里,牧在乡里,就近就地镇民化,建设高原美丽城市与城镇;以小聚大散为布局原则,聚散有度,在散聚中形成由“三圈四带多节点”构成“星星点灯”式固边型城镇空间格局,突出“三圈”（西宁都市圈、拉萨城市圈和柴达木城镇圈）、“四带”（青藏铁路沿线城镇带、川藏铁路沿线城镇带、唐蕃古道沿线城镇带、边境地区固边城镇带）和“多节点”（多个重要城市节点和重要固边城镇）的集聚效应;以通道建设为保障,超前建设青藏高铁等基础设施,筑牢国家安全保障线,加快引进“新基建”上高原,建设高原智慧城市;加快边境城市土地制度改革,建设边境土地改革试验特区,以国土安全为重,在国家重大战略布局和国土空间规划中优先考虑边境城市。

Various methods of spatial analysis are commonly used in land-use plans and site selection studies. A historical overview and discussion of contemporary developments of land-use suitability analysis are presented. The paper begins with an exploration into the early 20th century with the infancy of documented applications of the technique. The article then travels through the 20th century, documenting significant milestones. Concluding with present explorations of advanced technologies such as neural computing and evolutionary programming, this work is meant to serve as a foundation for literature review and a premise for the exploration of new advancements as we enter into the 21st century.

Land-use suitability analyses are of considerable use in the planning of mega-cities. An Urban Development Land-use Suitability Mapping (UDLSM) approach has been constructed, based on opportunity and constraint criteria. Two Multi-criteria Evaluation (MCE) methods, the Ideal Point Method (IPM) and Ordered Weighted Averaging (OWA), were used to generate the opportunity map. The protection map was obtained by means of constraint criteria, utilizing the Boolean union operator. A suitability map was then generated by overlaying the opportunity and protection maps. By applying the UDLSM approach to Beijing, its urban development land-use suitability was mapped, and a sensitivity analysis undertaken to examine the robustness of the proposed approach. Indirect validation was achieved by mutual comparisons of suitability maps resulting from the two MCE methods, where the overall agreement of 91% and kappa coefficient of 0.78 indicated that both methods provide very similar spatial land-use suitability distributions. The suitability level decreases from central Beijing to its periphery, and the area classed as suitable amounts to 28% of the total area. Leading attributes of each opportunity factor for suitability were revealed, with 2256 km(2), i.e. 70%, of existing development land being overlaid by suitable areas in Beijing. Conflicting parcels of land were identified by overlaying the resultant map with two previous development blueprints for Beijing. The paper includes several recommendations aimed at improving the long-term urban development plans for Beijing. Copyright © 2014 Elsevier Ltd. All rights reserved.

Taking Nagqu county in the alpine pasture of Tibetan Plateau as a case study, this paper built a land suitability evaluation index system of settlements, assessed the suitability of the land for the layout of settlements and its suitability grade in the study area using self-organizing mapping neural network (SOFM), evaluated the land suitability of current settlements, and further explored the paths of settlement reconstruction. The results showed that: (1) Nagqu county had a low level of land suitability for the layout of settlements. Suitable and sub-suitable areas, scattered in valleys with low elevations and flat terrain, only accounted for 12% of the total land area. Other areas of poorer suitability were relatively concentrated, accounting for 88% of the total land area. There were obvious differences among various townships and towns in the land suitability of settlements. (2) The current settlements of Nagqu county covered an area of 75.94 km², accounting for only 0.47% of the total land area. Areas where the suitability level was generally suitable and above accounted for 86.47%. About 13.53% of settlement area was distributed in hardly suitable, unsuitable, or prohibited construction areas. The layout of settlements in various townships and towns tended towards high-grade suitability areas. The better the environmental conditions, the more reasonable the layout of settlements; and vice versa. Lack of planning guidelines, irrational setting of administrative villages, local identification with specific survival spaces, and worshipping of mountains by Tibetans all contributed to the unreasonable layout of settlements in Nagqu county. (3) Ecomigration, "village-oriented" development in suitable areas, and other promotion factors can be integrated to realize the spatial reconstruction of settlements. Through constructing the central villages and towns system supported by characteristic industries and giving full play to the element diffusion role of the "point-axis" system, restructuring can be promoted to achieve the economic restructuring of settlements. By means of improving the allocation of public service facilities, enhancing the degree of social organization, strengthening the inheritance of Tibetan culture, and promoting the optimization of other functions, the social restructuring of settlements will be accomplished.

本文建立了适用于高寒牧区的聚落布局适宜性评价体系,利用自组织神经网络（SOFM）对青藏高原藏北地区那曲县展开聚落布局适宜性评价,并评估其现状聚落布局的合理性,在此基础上提出其聚落未来重构的思路。结果表明:（1）那曲县对于聚落布局的适宜性整体较低,适宜性水平高于一般适宜的区域零散分布在海拔较低、地势低缓的河谷地区,仅占全县面积的12%。其他适宜性较低的区域占全县面积的88%,分布相对集中。不同乡镇对于聚落布局的适宜性差异显著。（2）那曲县现有的聚落空间占全县总面积的0.47%,为7594 hm²,其中分布在一般适宜及以上等级区的面积占聚落总面积的86.47%,而较不适宜、不适宜和禁建区内的聚落占比高达13.53%。那曲县聚落空间布局倾向于较高级别的适宜区,聚落用地适宜性条件较好的乡镇其布局合理性越高。那曲县局部聚落布局不合理的原因包括:缺失空间布局指引、村级行政区划欠佳、藏民对神山的宗教信仰和历史遗存的地域环境认同。（3）聚落的空间重构可推动生态移民、适度“村庄化”等要素的整合来实现。聚落的经济重构要建设由特色产业为基础的村镇系统、充分利用“点—轴”结构的辐射效应等结构要素的重组来实现。聚落的社会重构需要通过合理安排基础设施、增强藏族社会关系组织程度、提倡藏区优秀文化传承等优化功能的措施来实现。

Geography is a subject which perceptibly reveals integration and regionalism. The integration means that the diversiform subjects in which geography is involved, and that the regionalism of geography is reflected by the regional differentiation. Through the comprehensive study of the interrelationships among the constituent elements of earth system and the relationship between natural and human systems, it helps us understand the variations of the past, present and future of earth system, and grasp the essence of these changes. Pattern helps us to understand the external features of the world and the process is conducive to the understanding of the internal biophysical mechanism of the world. On the basis of field observations and long-term comprehensive surveys, coupling of patterns and processes at different spatiotemporal scales is an effective way to understand and solve the problems in the field of geography. By analysis of the case studies in the Loess Plateau, the methods of coupling the patterns and processes in the integrated research of geography are discussed and explored.

地理学是一门以综合性和区域性见长的学科。地理学的综合性通过要素多样化来体现,区域性则表现为区域分异或区域差异。地理学综合研究是对地球表层各要素的相互作用以及人地关系的研究,帮助我们认识地球表层系统的过去、现状和未来的趋势,把握其变化的脉搏。格局是认识世界的表观,过程是理解事物变化的机理,基于长期的野外观测和综合调查以及模型模拟,对不同时空尺度下的地理格局与过程进行耦合研究,是从机理上理解与解决地理学综合研究的有效途径与方法。文章结合在黄土高原地区的相关研究案例,探讨了将格局与过程耦合研究的地理学综合研究的途径与方法。

The existing human activity suitability evaluation of land resources in China has the defects of insufficient theoretical support in terms of basic data accuracy, elevation and slope classification and suitability grade judgement. When it is applied empirically, there are some problems such as excessive evaluation factors, difficulty in obtaining indicator data, and low altitude of applicable regions. In this paper, we constructed a technical evaluation framework applicable to the Qinghai-Tibet Plateau, and established a grid-scale evaluation model for construction land suitability and cultivated land suitability after selecting key parameters that vary with topographic elevation and slope. And then we proposed a generalized algorithm for key parameters such as atmosphere density, air temperature, slope suitability for construction, and soil erosion resistance of sloping cultivated land. With Milin County in southeastern Tibet as an example, the empirical research has been carried out according to the interval of 100 m in elevation and 1° in slope. In addition, grid precisions of 30 m, 50 m, 100 m, 250 m, 500 m, and 1000 m are tested. This article obtains four conclusions: (1) The construction land suitability and cultivated land suitability can be classified into five levels: suitable, relatively suitable, moderately suitable, less suitable, and unsuitable. Under the grid precision of 30 m, the five levels of construction land suitability account for 1.26%, 2.92%, 2.12%, 2.77%, and 90.93%, respectively. Compared with 30 m, the area ratio results of 50 m, 100 m and 250 m have the errors of ±0.34%, ±0.34% and ±1.11%, respectively. Similarly, the area ratio of each level of cultivated land suitability with a 30 m grid precision is 0.72%, 3.07%, 2.62%, 1.35%, and 92.25%, the errors between it and the results under grid precision of 50 m, 100 m, and 250 m are ±0.52%, and the errors of 500 m and 1000 m grid precisions for both construction land suitability and cultivated land suitability are relatively larger than those of the other grid precisions. (2) Current construction lands (i.e., settlements of cities, towns and villages, industrial and mining lands) in the study area are mainly distributed in areas with levels of relatively suitable, suitable, and moderately suitable according to the distribution ratio. Under grid precisions of 30 m, 50 m, and 100 m, the total land areas of these three levels account for 95.96%, 95.96%, and 94.74%, respectively. Current cultivated land and plantation land are distributed in areas with levels of relatively suitable, moderately suitable, and suitable, accounting for more than 96% of different grid precisions. (3) The empirical research shows that evaluation method, quantitative model, and parameter algorithm for evaluating the human activity suitability of land resources in the Qinghai-Tibet Plateau are feasible and applicable. In the actual evaluation, the grid precision should be controlled within 100 m, and the maximum cannot exceed 250 m. (4) This study established a corresponding pedigree between construction land suitability and cultivated land suitability and topographic elevation and slope that can be applied to the Qinghai-Tibet Plateau. Meanwhile, some professional defects are analyzed of available land resources evaluation methods in major function-oriented zoning and "Double Evaluations" of territorial spatial planning in China when applied to the Qinghai-Tibet Plateau.

针对中国现有土地资源人类活动适宜性评价方法存在的问题,搭建了适用于青藏高原的评价流程框架,建立了基于栅格单元的建设用地和耕地适宜性定量评价模型,提出了空气密度、气温、坡地适建、坡耕地土壤抗蚀等关键参数的普适性算法,并以藏东南米林县为例进行了实证研究。结果表明：① 米林县建设用地和耕地适宜性可划分为适宜、较适宜、一般适宜、欠适宜、不适宜5个等级类型,30 m精度建设用地各适宜性等级面积占土地面积比例依次为1.26%、2.92%、2.12%、2.77%和90.93%;50 m、100 m各等级面积较30 m误差±0.34%,250 m误差 ±1.11%,500 m、1000 m误差较大。30 m精度耕地各适宜性等级面积占土地面积比例依次为0.72%、3.07%、2.62%、1.35%和92.25%;50 m、100 m、250 m与30 m误差±0.52%,500 m、1000 m误差较大;② 米林县现状城镇村及工矿用地主要分布在建设用地较适宜、适宜和一般适宜等级类型,30 m精度三者合计占比达95.96%,50 m、100 m占比分别为95.96%和94.74%。现状耕地和种植园用地主要分布在较适宜、一般适宜和适宜等级类型,3种栅格精度下三者合计占比大于96%;③ 业已建立的评价方法、定量模型及参数算法是可行的和适用的,青藏高原建设用地和耕地适宜性评价的适宜栅格精度为100 m,最大不超过250 m;④ 建立了可应用于青藏高原的土地资源建设用地和耕地适宜性等级类型与地形高程及坡度对应谱系。

Cultivated land suitability evaluation of the plateau is an important prerequisite to promote the planning of regional agricultural development and the construction of food security system. This paper takes cultivated land of 18 counties in the Yarlung Zangbo River, Nyangqu River and Lhasa River (YNL) region of Tibet as the object of evaluation. The fuzzy weight of evidence model is introduced to screen out nine factors included in the four aspects of topography, climate, soil and water conditions as evidence layers, calculate the fuzzy weight of evidence of factor layer, and finally synthesize parameters of all factor layers to calculate posterior probability weight and revise it to format a distribution map of cultivated land suitability. The study shows that: 1) 80.83% of the known suitable points are above moderately suitable level in the grading figure of modified posterior probability, reflecting a high coherency, which indicates that the fuzzy weight of evidence connecting with modified posterior probability can evaluate the suitability of cultivated land scientifically and effectively. 2) Fuzzy weight of evidence model, which is both data-driven and knowledge-driven, can give full play to the prior knowledge and the role of objective laws. It can also increase the intervention of knowledge by the membership function, effectively using the experience of experts, which, to some extent, avoids arbitrariness in selecting indicators and determining the weight in the knowledgedriven method and overcomes the weakness of purely data-driven method. 3) Highly suitable, moderately suitable, generally suitable and unsuitable culti-vated land in the study area cover 213200 hm2 of cultivated land, accounting for 32.03%, 31.94%, 27.19% and 8.84% respectively, which corresponds to the spatial distribution. This can optimize the scale and layout of cultivated land and also can be used in the practice of cultivated area on the plateau to promote the rational utilization and management of cultivated land.

开展耕地适宜性评价是编制农业发展规划、优化耕地资源配置的基础性工作。文章以西藏一江两河流域18 个县的耕地资源为评价对象，将模糊证据权模型引入到耕地适宜性评价中，通过该方法筛选出地形地貌、气候、土壤和水资源状况等4 个方面的9 个因子作为证据图层，并计算因子图层的模糊证据权重，最后综合各因子图层的证据权重参数得出后验概率并修正形成耕地适宜性分布图。结果表明：①80.83%的适宜样本点处于修正后验概率分级图的中等适宜级别及以上，即已知信息体现出较高的吻合性，表明模糊证据权模型能够科学、有效地评价耕地资源的适宜性；②集知识驱动与数据驱动一体化的模糊证据权模型既能够充分发挥先验知识、客观规律的作用，也可以通过隶属度函数增加知识干预，有效利用专家的丰富经验，在一定程度上克服了知识驱动方法中因子筛选和权重确定主观性强或纯粹数据驱动方法的不足；③研究区21.32×10⁴hm²的耕地资源中，高度适宜、中度适宜、一般适宜和不适宜的耕地资源分别占32.03%、31.94%、27.19%和8.84%，对应其空间分布情况，可以优化耕地资源规模与布局，指导高原耕地区农业生产实践，促进耕地资源的合理利用。

Urban planning construction land standard is the technical specification for allocating various types of urban construction land scientifically, and is the basis for drawing up and revising the overall urban planning as well. In view of China's current urban planning construction land standard, there are many problems such as the big gap of land use control threshold, the lack of regional differences in climate revision, and ignorance of the topographical and geomorphological factors. To solve these problems, this paper proposed a step-by-step process framework and quantitative calculation method for the establishment and revision of standards in accordance with the principle of "total-structure" control. Through the setting of conditions, a universal basic standard for construction land was established. Then quantitative analysis was made for the relations between each index and the basic standard with the selected key indicators such as urban population size, sunshine spacing coefficient, valley area (intermountain basin) width and terrain slope. Finally we formed a revision standard for climate, topography and geomorphology which is matched with the basic standard. The main results are as follows: (1) The per capita construction land area of 95 m 2/person can be used as the total indicator for the basic standard of urban planning in China. The percentage of corresponding per capita for each type of construction land is 32.5% for residential land, 7.42% for public administration and public service land, 22.5% for industrial land, 17.5% for transport facilities, 12.5% of green land, and 7.58% of other types of land. The results of revision value of urban population scale shows that the impact of population size difference on the per capita construction land is relatively weak. (2) The climate revision results of per capita residential land and per capita construction land in major cities show that the climate revision value varies greatly between northern and southern China. The climate revision value of the per capita area of construction land varies by latitude as follows: the figure for 20° north latitude is 93 m 2/person; the figure for 30° north latitude is 97 m 2/person; the figure for 40° north latitude is 103 m 2/person; and the figure for 50° north latitude is 115 m 2/person. The basic standard value of 95 m 2/person is roughly distributed along the Xiamen - Guilin - Kunming line. (3) The cities located in mountainous areas, hilly valleys or intermontane basins can reduce the allocation of community parks and comprehensive parks when the average width of river valley or intermontane basin is less than 2 km. When the average width of the valley or intermontane basins is between 2 km and 4 km, the allocation of the comprehensive parks can be reduced. The revised results of per capita land for construction use on slopes indicate that the terrain slope has a great impact on the revised value of per capita construction land. The revised value at 3° is 3.68% higher than the baseline value, and the increases of 8°, 15° and 25° are 11.25%, 26.49% and 68.47%, respectively.

城市规划建设用地标准是科学配置城市各类建设用地的技术规范和编制、修订城市总体规划的基础。针对中国现行城市规划建设用地标准存在的用地指标控制阈值高低差距较大、气候修订缺乏地域分异和地形地貌因素缺失等问题,本文按照“总量—结构”控制的建标思路,提出了标准建立、修订的分步式流程框架和定量测算方法,通过条件设定建立了普适性的建设用地基础标准,进而选择城市人口规模、日照间距系数、河谷地（山间盆地）宽度、地形坡度等关键指标,定量分析了各指标与基础标准之间的关系,形成与基础标准配套的气候和地形地貌修订标准。主要研究结果包括：确定了设定条件下适用于全国不同地区的由人均建设用地面积和人均单项用地类型结构控制的建设用地基础标准;按城市人口规模等级对基础标准进行了量化修订;定量测算了人均居住用地面积随日照间距系数变化的情况,提出了按纬度方向变化的人均建设用地气候修订标准;阐释了河谷地（山间盆地）宽度变化与公园绿地的配置,量化分析了地形坡度与人均建设用地面积变化的关系,建立了针对山地、丘陵地区城市规划建设用地的地形地貌修订标准。

The Qinghai-Tibet Plateau is an important ecological barrier area in China and Asia.Conducting construction land suitability evaluation (CLSE) and arable land suitability evaluation (ALSE) is important for ecological protection, restriction of human activity space in this plateau. However, the application has the defects of existing CLSE and ALSE models and methods in high-altitude areas. In this paper, we constructed CLSE and ALSE models applicable to alpine-gorge region in the Qinghai-Tibet Plateau, as well as proposed the measurement methods of four control parameters: air density, sloping land suitability for construction, air temperature and soil erosion resistance of sloping land. Based on the standard scenarios of elevation-slope classification with an interval of 100 m in elevation and 1° in slope, an empirical application research was carried out in Nyingchi city, the typical area of alpine-gorge region in the Qinghai-Tibet Plateau, and the feasibility was demonstrated of two different elevation-slope classification scenarios for CLSE and ALSE as well. This article obtains four conclusions: (1) Construction land suitability (CLS) and arable land suitability (ALS) in Nyingchi city can be divided into five grade types: suitable, relatively suitable, moderately suitable, less suitable, and unsuitable. The grade type of CLS and ALS is mainly unsuitable in the city, with 87.48% and 87.42% area ratio of unsuitable grade type, 5.58% and 4.58% area ratio of less suitable grade type, and sum area ratio of suitable, relatively suitable, moderately suitable grade types accounted for only 6.94% and 7.60%. (2) The matching degree is high of CLS and ALS with current construction land and arable land under standard scenario in Nyingchi city, with the matching accuracy reaching 93.59% and 90.89%, respectively, among which the matching accuracy in Mainling county, Chagyib district, and Bowo county is above 95%, and the matching accuracy in Gongbo' gyada county, Nang county, and Mêdog county is very low, respectively. (3) The matching accuracy is 93.11% and 91.28% of CLS under scenarios 1 and 2, and its matching error is -0.48% and -2.31% with the standard scenario. The matching accuracy is 91.52% and 91.54% of ALS under scenarios 1 and 2, and its matching error is +0.63% and +0.65% with the standard scenario. The model error is within an acceptable range. (4) Classification schemes with an interval of 500 m in elevation and 3°, 5°, 8°, 12°, 15°, 20°, and 25° in slope are applicable for CLSE and ALSE in alpine-gorge region of the Qinghai-Tibet Plateau.

青藏高原是中国乃至亚洲的重要生态屏障区，进行建设用地和耕地适宜性评价对于青藏高原生态保护、严格人类活动空间具有重要意义。针对中国现行建设用地和耕地适宜性评价方法在高海拔地区应用中存在的不足，分别构建了适用于青藏高原高山峡谷区的建设用地和耕地适宜性评价模型，提出了空气密度、坡地适建、气温和土壤抗蚀四个控制参数测算方法；以100 m间隔高程分级和1°间隔坡度分级为基准情景，选择林芝市为典型案例开展实证应用研究，并对两种增大高程和坡度间隔分级情景进行论证。结果表明：（1）林芝市建设用地和耕地适宜性均以不适宜为主体，不适宜区面积占土地总面积比例分别为87.48%和87.42%，欠适宜区比例分别为5.58%和4.58%，适宜、较适宜和一般适宜区的面积之和占比分别仅为6.94%、7.60%；（2）基准情景下建设用地和耕地适宜性评价结果与现状建设用地和耕地的适配效果较好，适配精度分别达到93.59%和90.89%，米林县、巴宜区和波密县的适配精度达到95%以上；（3）情景1和情景2下建设用地适宜性的适配精度与基准情景的误差分别为-0.48%和-2.31%，耕地适宜性的适配精度与基准情景的误差分别为+0.63%和+0.65%，误差处于可接受范围；（4）500 m高程间隔和3°、5°、8°、12°、15°、20°、25°的坡度间隔适用于青藏高原高山峡谷区建设用地和耕地适宜性评价。

The changes in the scale and structure of built-up land is the basis for spatial development and planning of the national territory. Previous studies mainly focused on the characteristics and patterns of the horizontal expansion of built-up land, but little attention has been given to the "three-dimensional" gradient characteristics and effects of built-up land (such as slope-climbing). Therefore, based on Google Earth Engine, this study, for the first time as far as we know, uses DEM and land use data to draw built-up land slope spectrums and calculates the average built-up land climbing index (ABCI). The gradient characteristics and laws of the slope climbing of China's built-up land from 1990 to 2018 at the national, regional, provincial, and urban scales are systematically analyzed and the various spatial effects are explored. The results show that: (1) From 1990 to 2018, the area of built-up land with slope angle above 5° in China increased by 1.43 times, and the proportion of the total built-up land area rose from 10.25% to 14.81%. Particularly, the 2010-2015 period witnessed the fastest and largest slope-climbing development of built-up land in China. Moreover, the slope-climbing intensities in the central and western regions are higher than that in other regions. (2) According to the average built-up land climbing index (ABCI) and the upper limited slope angle change (ULSC), the 34 provinces (autonomous regions and municipalities) in China can be divided into three types: high-climbing, low-climbing, and horizontally expanding. Among them, the number of high-climbing provinces accounts for more than 50% of the total. And seven horizontally-expanding provinces present the distribution characteristics of "southeast-northwest" in space. (3) Before 2010, the cities with slope-climbing phenomenon were mainly mountainous cities. However, ethnic minority settlements and low-hill and gentle slope development pilot cities became the main force for the slope-climbing of built-up land after 2010. (4) The slope-climbing of built-up land can reduce the occupation of plain arable land and ecological land by built-up land expansion to a certain extent, and thus alleviate the contradiction between supply and demand of build-up land. However, it is worth noting that development and construction without reasonable plans and bulldozing mountains to build cities driven by real estate can also lead to increased geological disasters and ecological risks.

城镇建设用地规模与结构变化是国土空间开发与规划研究的基础。以往相关研究更关注建设用地水平空间扩张格局特征与模式,极少关注建设用地三维梯度上的“爬坡”特征规律与影响。因此,本文基于Google Earth Engine（GEE）,并结合高精度地形数据与土地利用数据,在建设用地坡谱概念基础上,首次构建了平均建设用地爬坡指数（ABCI）,系统地分析了1990—2018年中国建设用地坡谱在国家、区域、省级和城市4个尺度上的变化特征与规律并深入剖析建设用地爬坡的空间影响。结果显示：① 1990—2018年中国坡度5°以上地区建设用地面积增长了1.43倍,比例由10.25%上升至14.81%。其中2010—2015年是建设用地爬坡发展最迅速与规模最大的时期,且中西部地区建设用地爬坡最为显著。② 依据平均建设用地爬坡指数与上限坡度变化,可将中国34个省（自治区、直辖市）划分为高爬坡型、低爬坡型和水平扩展型3类,其中高爬坡型省份占50%以上,水平扩展型省份仅有7个,在空间上呈现“东南—西北”的两极分布特征。③ 1990—2010年爬坡型城市以山地与丘陵地貌城市为主,2010年后少数民族聚居区及低丘缓坡开发试点城市成为建设用地爬坡的主力。④ 建设用地爬坡在一定程度上能够减少建设用地扩张对平原优质耕地与生态用地的胁迫和侵占,缓解建设用地供需矛盾,但是无规划约束的开发和房地产驱动的“削山造地”则会导致地质灾害和生态环境风险的增加。

With the rapid urbanization, the land utilization rate in the mountainous areas has been increasing. Therefore, we should deepen our understanding of the construction land expansion in mountain cities, so as to carry out more scientific management of land use in mountainous areas. This paper studied the slope gradient effect of construction land growth in Guiyang, a typical mountain city in Southwest China, using digital elevation model (DEM) and construction land datasets of 2000, 2005, 2010, 2015 and 2020, which was integrated with zonal statistics approaches based on spatial statistics unit of kilometer grid and slope section with one degree interval. Combined with the information of construction land density and slope, we propose a novel method to quantify the spatial pattern of construction land climbing. The research was designed to address three research questions: Is there a synergistic relationship between the area of construction land and the average slope of construction land? What are the distribution and change characteristics of construction land density on the slope gradient? What is the relationship between the density of construction land and the heat of construction land climbing? The results showed that: (1) The total area of construction land is positively correlated with the average slope of construction land, both of which increase gradually across the entire study period. However, the average slope of new construction land gradually becomes steeper among four neighboring periods, while the area of new construction land turns from increasing to decreasing, implying that they are not synchronous. (2) The density of construction land in each period decreased with the increase of slope, no matter in one period or in the other four periods. (3) The density of construction land has a significant impact on the heat of construction land climbing, and this influence increases as the average slope of the background ground rises. This paper suggests that the phenomenon of construction land climbing would promote the intensification and compactness of construction land in mountain cities.

山地城市快速扩张致使其建设用地爬坡现象日趋普遍,深入认识该现象将有助提高山区国土空间管控科学性。以中国西南典型山地城市贵阳为例,利用数字高程模型和2000—2020年五期建设用地数据,构建建设用地密度、建设用地爬坡热度等指标,基于网格单元和坡度区段单元开展统计分析,探究该市建设用地增长的坡度梯度效应。结果表明：（1）建设用地面积的增长总体伴随着建设用地平均坡度的趋陡,各相邻时段新增建设用地面积先增大后减小,但新增建设用地平均坡度却一直在变陡;（2）各时期建设用地的现状密度和新增密度均随坡度上升而减小,在坡度梯度上体现出强烈的“择平而建”效应;（3）建设用地密度对建设用地爬坡热度有显著线性影响,且该影响随着背景地面平均坡度上升而增强。研究认为,建设用地爬坡现象通常更多出现在建设用地加密时期,这有利于促进山地城市实现更为集约紧凑的空间增长。

The spatial distribution of reserve available construction land overlaps with that of reserve available cultivated land in the resources and environmental carrying capacity and territorial development suitability evaluations of current territorial spatial planning. On the basis of elaborating the connotation of relevant concept, this study developed an integrated evaluation method of reserve available land resources, discussed the regional tendency of use of these two types of land, and took Jiexiu City in Shanxi Province as an example. The results are as follows: 1) Reserve available construction land in Jiexiu City had an area of 45.3 km 2, which was 6.1% of the total land area of the city. Its distribution was scattered. The reserve available construction land could be generally divided into three levels: highly suitable, suitable, and less suitable. The corresponding areas were 3.6 km 2, 16.1 km 2, and 25.6 km 2 respectively. The area of reserve available construction land per capita was 0.16 mu. 2) The area of the reserve available cultivated land was 74.1 km 2, which was 10% of the total. The reserve available cultivated land also could be divided into three levels: highly suitable, suitable, and less suitable. The corresponding areas were 21.7 km 2, 26.1 km 2, and 26.3 km 2respectively. The area of reserve available cultivated land per capita was 0.26 mu. There were similar spatial distributions between these two types of land in the study area. The potential of reserve available land resources in Mianshan and Lianfu towns was large, while the potential of the urban area and its surroundings was small. In view of the overlap and difference of spatial distribution between these two types of land, reserve available land resources in the urban area, town centers, and the northern part of the city could be used as construction land preferentially in the future. They should be classified as urban space. Reserve available land resources in the southern areas of Lianfu, Mianshan, Yitang, and Zhanglan towns could be transformed into new cultivated land. They should be classified as agricultural space.

针对当前国土空间规划“双评价”中存在的后备适宜建设用地与后备适宜耕地在城镇、农业空间分布上的重叠性问题,论文在对2类用地进行概念内涵辨析的基础上,尝试构建后备可利用土地资源集成评价方法,探讨不同类型后备可利用土地资源用途的地域导向,并选取山西省介休市作为案例区进行实证应用研究。结果表明：介休市后备适宜建设用地面积较大(45.3 km ²),但集中连片趋势不明显。人均后备适宜建设用地面积为0.16亩/人。区域后备适宜耕地面积74.1 km ²,人均后备适宜耕地面积为0.26亩/人。研究区域2类用地具有相似的空间分布格局,即绵山镇、连福镇等地区后备可利用土地资源潜力较大,而城区及周围地区的潜力较小。针对2类用地的重叠性和差异性,介休市城区、各乡镇中心及北部地区的后备可利用土地资源未来可转化建设用地,即未来应被划归城镇空间。连福、绵山、义棠、张兰等乡镇南部地区未来可转化为新增耕地,即应被划归农业空间。

Land-Use/land Cover Changes (LUCC) are a direct consequence of human and nature interactions. China's Land Use/cover Datasets (CLUD) were updated regularly at five-year intervals from the late 1980s to the year of 2010 with standard procedures based on Landsat TM/ETM + images. A dynamic zoning method was proposed to analyze major land-use conversions. The spatiotemporal characteristics, differences, and causes of land-use changes at a national scale were then examined. The main findings are summarized as follows: Land-Use Changes (LUC) across China indicated a significant variation in spatial and temporal characteristics in the past 20 years between the 20th and 21st centuries. The amount of cropland change decreased in the south and increased in the north, but the total area remained almost unchanged. The reclaimed cropland was shifted from northeast to northwest. The built-up lands were expanded rapidly, which were mainly distributed in the east and gradually spread out to the midwest. Woodland decreased first and then increased, but desert area was inverted. Grassland continued decreasing. Different spatial patterns of LUC in China were found between the late 20th century and the early 21st century. The original 13 LUC zones were replaced by 15 units with changes of boundaries in some zones. The main spatial characteristics of these changes included (1) an accelerated expansion of built-up land in the Huang-Huai-Hai region, the coastal areas of southeastern China, the midstream area of the Yangtze River, and the Sichuan Basin; (2) the shifted land reclamation in the north from Northeast China and eastern Inner Mongolia to the oasis agricultural areas in Northwest China; (3) the continuous transform from rain-fed farmlands in Northeast China to paddy fields; and (4) the effectiveness of the “Grain-for-Green” project in the southern agricultural-pastoral ecotones of Inner Mongolia, the Loess Plateau, and mountainous areas of southwestern China. In recent two decades, although climate change in the north impacted the change in cropland, policy regulation and economic driving forces were still the primary causes of LUC across China. During the first decade of the 21st century, the anthropogenic factors that drove variations in land-use patterns have shifted the emphasis from one-way land development to both development and conservation. The "dynamic zoning method" was used to analyze changes in the spatial patterns of zoning boundaries, the internal characteristics of zones, and the growth and decrease of units. The results revealed "the pattern of the change process," namely the process of LUC and regional differences in characteristics at different stages. The growth and decrease of zones during this dynamic LUC zoning, variations in unit boundaries, and the characteristics of change intensities between the former and latter decades were examined. The patterns of alternative transformation between the "pattern" and "process" of land use and the reasons for changes in different types and different regions of land use were explored.