The curves on the change of level of urbanization over time are called urbanization curves, which are in fact models of the progress of urbanization based on empirical evidences from developed countries and developing countries. There are two types of urbanization curves. One is S-shaped curve, and the other, J-shaped curve. The S-curve can be modeled with the logistic function, while the J-curve cannot be described by the logistic function. The former is applicable to the developed countries, whereas the latter is applicable to the developing countries. So far, there have been more studies on the S-shaped curve. However, fewer studies have been devoted to the J-shaped curve of urbanization. Consequently, we know little about the general principle on the J-shaped curve and its underlying rationale, which remain to be further explored in the future. In this paper, various studies on urbanization curves are systemized to form a framework of models on the level of urbanization. The logistic curve was once divided into three stages by Northam (1979): initial stage, acceleration stage, and terminal stage. However, the Northam's proposal is just a phenomenological theory with several defects: first, the definition of 'acceleration stage' is not correct; second, there are no theoretical basis and critical scale for the divisions. It can be proved that the logistic process falls into four phases. Taking half of urbanization level capacity as a tipping point, the logistic curve is divided into two stages: acceleration stage (urban majority) and deceleration stage (urban minority). The tipping point can be determined by two methods of elementary mathematics. Then the two stages are respectively divided into two sub-stages by means of the exponential law of urban-rural ratio with a parameter as characteristic length. Now, urbanization process can be divided into four stages: initial stage, acceleration stage, deceleration stage, and terminal stage. Also it can be divided into three stages: initial stage, celerity stage (including acceleration stage and deceleration stage), and terminal stage. Two methods are always applied to the research of urbanization curves and the related urbanization dynamics. One is phenomenological analysis, and the other, theoreticalogical analysis, which consists of three approaches: urban-rural allometric growth, urban-rural population replacement, and urban-rural population interaction dynamics. Urban-rural allometric growth analysis is a kind of scaling analysis. Urban-rural population replacement suggests a new dynamical analysis. Urban-rural interaction comprises linear dynamics and nonlinear dynamics. The linear dynamics is based on the well-known Keyfitz-Rogers model, whereas the nonlinear dynamical analysis can be employed to interpret the similarities and differences between the S-shaped and J-shaped curves. China’s urbanization process can be described with the J-shaped curve rather than the S-shaped curve. The studies on the urbanization curves will be significant for understanding the dynamical mechanism and essence of Chinese urbanization.

Many islets and reefs in South China Sea are main parts of China. The nine-dotted line is China’s maritime boundary line. To study the formation and evolvement of the nine-dotted line is not only a matter of maritime geopolitics, but also a matter of maintain sovereignty, protection of islets and reefs and resources management. How the nine-dotted line came into being is an academic topic that has not been studied much. Map is one of the means by which a country claims its territory. Besides demonstration in words, map-reading is used in this article to study the formation and evolvement of the nine dash lines to deline the South China Sea. The whole formation process is divided into three phases, namely the initial phase, taking-shape phase, and the final phase. Time before the 1930s witnessed the appearance of the maritime boundary line in South China Sea. The boundary line took shape in the 1930s, and its evolvement came to the final stage in the 1940s-1950s. The original continuous line demarcation and the dotted line demarcation in this sea area can all be found on maps in that period. The maps clearly showes how the eleven-dotted line demarcation changes to the current nine-dotted line demarcation. With the formation and evolvement of the nine-dotted line clarified, the historical fact could be confirmed that China has sovereignty over the islets and reefs within the line. The nine-dotted line is the final maritime boundary line of China.

Markedly, our understanding of hazard has changed with history, and the hazard paradigm is also in the process of evolution. Based on different hazard concepts and human reaction, there are five hazard paradigms recognized as following: famine policy paradigm, engineering paradigm, behavioral paradigm, social vulnerability paradigm and sustainable paradigm. Famine policy paradigm originated from the pre-Qin period of China, which of main features are as following: Catastrophes are created by nature; Disaster alleviation is main responsibility of the government represented by the emperor; The policy of benevolence is the principal implementing policy against natural disasters. In the 20th century, engineering paradigm was the mainstream paradigm in the world. This paradigm concerns those issues such as the regularities of natural disasters occurrence; the strength and frequency of the potential natural disasters in different region; and the methods of disasters resistance for protection. In the 1930s, behavioral paradigm appeared in the western developed countries. The main points of this paradigm are as following: human perceptions and behaviors influence the consequences of natural disasters, but disaster is a natural process primarily; The principal goal of disasters management is resistance extreme events through project management control; The basic preventive measures include improving disasters early warning for short-term and preparation better land-use planning for long-term. Social vulnerability paradigm came from experience of some western scholars in the developing countries in the 1970s. They discovered the developing countries suffered enormously from natural disasters. They thought the main cause of disaster is human behavior rather than nature and technology development. According to social vulnerability paradigm, the disasters reduction depends on the social- economic and political reform. Sustainable paradigm was growing up as a new inspiration at end of 20th century. This paradigm examines the essence of disaster from view of complex interaction between human society and natural environment. The basic principles of disaster reduction are to maintain and improve the quality of natural environment and living condition of people, to ensure the justice that the same and different generations have the same right to enjoy the resources and environment and the publicaction based on common; to promote regional sustainable development through integrated capacity-building of regional disaster risk management. The final goal of the paradigm is establishment sustainable society and achievement of human coexistence. The author analyzes the five paradigms’ formation of social and historical background, the principal issues, the main points and measures of disaster reduction, the conclusions are as follows: 1) Recognition and understanding of hazards and disasters is deepening and developing gradually through human history; 2) Development of hazard paradigm and practice of disaster reduction are mutual influence; 3) The generation and transformation of paradigms are impacted by social factors deeply; 4) Individual hazard paradigm often rises to dominance for a period of time, but the impact of other paradigms is still exist.

Northeast China is considered as the important old industrial base. However the change of population distribution and driving factors were not clear yet under the circumstance of a new round of revitalization. Therefore, according to the population census data in 1990, 2000 and 2010, Lorenz curve, relative change rate of population density and Moran’s I are employed to analysis spatial pattern evolution of population distribution in Northeast China in 1990-2010, which consist of 176 counties. Subsequently, based on the partial least squares (PLS) regression method, 10 natural and social-economic factors are recognized to make quantitative analysis on spatial pattern evolution of population distribution in Northeast China. Major conclusion can be drawn as follows: 1) From the stand point of overall distribution pattern changes in nearly 20 years, average population density shows: Heilongjiang Province< Jilin Province

The Chinese cities are experiencing the process of rapid globalization and urbanization, which makes the process of urban structure transforming more complicated. The relationship between the spatial layout of logistics and urban structure is meaningful to the urban theory and urban planning but less discussed. This article takes Chongqing’s urban area as a case, one of biggest cities and logistics center in western China, to analyze the influence of logistics parks to urban structure. We collected data by field work in all the logistics parks, especially by deeply interviewed with the managers of logistics parks and the officers from government. Firstly, we reviewed the development process of logistics parks in Chongqing City. Although it developed later, it has been experiencing a rapid industrialization process with a fast speed. Secondly, two location preferences of the logisitcs parks were found: one is near main road or main transportation terminal; the other is far from the urban center area; Thirdly, we argued that logistics parks have close relationship with the urban spatial structure. On the one hand, logistics parks locating outside of the urban area had led the sprawl of urban area through the transportation oriented development; on the other hand, they brought changes to the urban internal structure and function by guaranteeing the logistics land space and promoting the development of surrounded area. Fourthly, an interaction mechanism framework was conducted with urban governance factors and economical impacts. Finally, this article suggests that the direct and indirect interaction between the logistics park and urban structure should have different performance with different logistics parks. The future direction of research should be more cases study about the logistics parks and urban structure.

Based on daily average, maximum and minimum temperature observed by the China Meteorological Administration at meteorological station in Beijing from 1960 to 2014. Sixteen indices of extreme temperature are studied. Applying the method of Rhtest, the series that have breakpoints are adjusted and the trends of the series are analyzed, the annual temperature trend has changed obviously and the homogeneity is improved well. The results showed that: 1) In general, the temperature increment is obvious in Beijing during 1960-2014, with generally stronger increases in minimum temperature than in maximum temperature, as for climate inclination rate after adjustment: the maximum temperature (0.17℃/10a)-1.43, -6.56, -3.95, -1.18 and -4.83 d/10a days/decade respectively. 3) While the occurrence of warm days, warm nights, summer days, tropical nights, warm spell duration days and growing season length shows statistically significant increasing trends at rates of -2.12, 5.27, 1.22, 5.43, 0.84 and 1.96 d/10a days/decade respectively. 4) The tendency rate of annual minimum value of daily maximum (minimum) temperature, annual maximum value of daily maximum (minimum) and diurnal temperature range is 0.18, 0.23, 0.46, 0.73 and -0.36℃/decade respectively. 5) The magnitudes of changes in cold indices (cold nights, ice days, frost days, cold spell duration days) are obviously greater than those of warm indices (warm nights, warm spell duration days, summer days). The change ranges of night indices (warm nights and cold nights) are larger than those of day indices (warm days and cold days). The change ranges of minimum-temperature-related indices (annual minimum value of daily maximum, annual minimum value of daily minimum) are larger than those of maximum-temperature-related indices (annual maximum value of daily maximum and annual maximum value of daily minimum). This explains the stronger warming in the past 55 years in Beijing due to the change of night indices, cool indices and minimum-temperature- related indices.

Based on the structured questionnaires, this article uses the methods of questionnaire investigation and interview to analyze the spatial pattern and regional characteristics of rural poverty in Northeast China, and then the formation mechanism of poverty problems in the typical rural poor areas is discussed and deconstructed. The main conclusions are as follows. 1) The rural poor population and poor counties in Northeast China are centrally distributed in the southern piedmont region of the Da Hinggan Mountains, the provincial boundaries between three provinces and the eastern part of Inner Mongolia, and the border areas of Sino-Korean and Sino-Russian. At the same time, there are 2 major poverty areas in the east and the west: the west area extends from north to south in a belt, and two mass poverty population concentrated areas are in the east area. On the whole, the poor population shows the spatial distribution characteristics of “big agglomeration and small dispersion”. 2) There are 5 high incidence areas of rural poverty in Northeast China, including the northern and eastern border of Sino-Russian, the Songnen Plain, the west, and the border areas of Sino-Korean. The incidence of poverty is high in the north and east, low in the south and west. 3) The poor are mainly consisted in the middle-aged and elderly people with a low educational level. At the same time, their food and clothing and medical security problems are severe. Disease, lack of cultivated land and low utilization rate of cultivated land, are the main causes of rural poverty in Northeast China, thus developing modern agriculture and going out to work are important ways to eliminate poverty. 4) In Northeast China, there are 3 typical rural poverty areas: the farming and pastoral transitional zone of the western region, Korean nationality community of the eastern border mountainous region, and the eastern plains and hills transition zone. The poverty in the western region is mainly affected by the single agricultural structure, low agricultural product market prices, backward farmers' understanding of their own ideas, weak infrastructure construction and harsh natural ecological conditions. While the rural poverty in the Korean nationality community in the eastern border mountainous areas is mainly caused by the continuous outflow of the working age population. And the emergence of rural poverty in the transition areas of the eastern plain and hilly areas is mainly affected by the remote location and complicated topography, which leads to natural disasters and the shortage of cultivated land resources.

In order to understand the windbreak and sand fixation effects of the Three-North Shelter Forest Program (TNSFP) in recent 35 years, this paper analyzes the amount change of ecosystem sand fixation caused by climate change and vegetation degradation or restoration in the project region, and then assesses the sand fixation effects of the Program. Based on Landsat MSS, TM/ETM+, and environmental satellite (HJ) images, the spatial-temporal datasets of land cover changes in the project region of TNSFP were analyzed in the periods of mid 1970s, 1990, 2000, 2010, 2015, especially the forest and grassland. Combining the NDVI data of AVHRR and MODIS, the vegetation coverage was estimated, and then the change of vegetation coverage in the 1982-2015 was analyzed. The soil erosion modulus were estimated at the regional scale by applying the soil erosion equation (RWEQ), and then the ecosystem services of windbreak and sand fixation were assessed using indicators of amount and retention rate of windbreak and sand fixation. Then the contribution rate of ecological program and climate change to regional ecosystem change was determined by comparing the indexes under the conditions of average climate and real climate. The results showed that: 1) In the past 35 years, the area of forest was continuously increased and grassland was decreased, especially in the semi-arid sandy area and Loess Plateau. The vegetation coverage increased continuously in the before 20 years, and then decreased in recent 15 years. 2) The soil wind erosion modulus is decreased continuously, and the decreasing rate in recent 15 years is much higher than that in the before 20 years. The decreasing rates were especially obvious in sandy land, grassland, and regions planting trees and grassland. The retention ratio of ecosystem windbreak and sand fixation service also increased continuously, especially in arid desert area. Grassland and sandy land contributed 71% of the total amount of windbreak and sand fixation. However, just 6.6% of forest land, and the contribution of conversion grassland was higher than that of conversion forest. 3) In the TNSFP, the weakening of wind erosion force due to reducing wind, and the vegetation restoration in local areas due to TNSFP and other ecological programs, both resulted in a decrease of soil wind erosion, and accounted for 85%-89% and 11%-15% of the decrease. Winter monsoon in mid-latitude Asian is weakened due to global warming. In the project region of TNSFP, the grassland played the most important role in ecosystem service of windbreak and sand fixation, which accounts for more than 63% of the total area. Therefore, the conservation of grassland and sandy land were significant in project region of TNSFP. Project planning and implementation should focus on the transfer of funds from afforestation to grassland conservation and restoration.

This study focuses on the distribution characteristics, effect factors and optimized reconstructing analysis of rural settlement in China. Based on electronic map data in 2012 and socioeconomic data of counties in China, the spatial distribution pattern of rural settlement and effect factors have been examined using model of the average nearest neighbor distance and geographical detector method, while the background and mode for rural space optimization reconstruction were analyzed. Main results for this study are as follows: 1) the rural settlement spatial distribution mode consists of cluster, random and uniform discrete distributions in China, while the regional differences were significant. The density of rural settlements is greater in the southeastern region than in the northwest region with Hu Huanyong's population distribution line for the boundary in China. There were a variety of characteristics for the rural settlement distribution in different type of regions. The spatial distribution of rural settlement was intensive, and those spatial distribution modes were mainly random and disperse with a short average nearest neighbor distance in plain areas. On the other side, the density of rural settlement was low, and those spatial distribution modes were mainly cluster relatively with a long average nearest neighbor distance in highland and cold areas and fringes of the desert. In addition, the density of rural settlement was high, and those spatial distribution modes were mainly random in the intersected transition zone between hill and mountain. 2) The dual factors affect the rural settlement distribution from traditional and economy. Although the traditional factors still play a significance role, the influence of the economic developed more and more obviously. There were a large amount of factors attributing to impacting rural settlement distribution, the spatial form of production and life space, including natural topography and water resources natural conditions, etc. That also included traffic condition, industry, economic development level and agricultural modernization. 3) With factors of production non-agriculture in rural region, the rural space need be a reconstructing optimization. The priority selection is to rebuild village-town system for optimizing rural physical space. Theoretically, village-town system is a sort of hierarchical structure, consisting of central regional town, general agricultural town, central village and basic village. 4) The multiple modes will been made use of restructuring rural space in different geographical areas, including balance forms of radiation, radiation disequilibrium forms, multicore equilibrium forms and corridor layout pattern or mixed modes. From the system and the hierarchical logic level to deconstruct the rural space theory for optimization, a reasonable village-town system is rebuilt orderly, which will provide a scientific basis for urban and rural urbanization.

The Qingyijiang River which rises on the Huangshan Mountain, flows northward through the northern piedmont of the Huangshan Mountain and eventually discharges into the Yangtze River at Wuhu City, Anhui Province, the eastern China. As the longest right-bank tributary of the lower reaches of the Yangtze River, the Qingyijiang River is a typical representative of the small and medium rivers in the Eastern monsoon area of China, providing a typical case for studying the developmental history of the small and middle rivers. Based on the results of previous studies and the analyses of external environmental factors, the development causes of the Qingyijiang River and its relationship with the channelization of the Yangtze River were emphatically analyzed and discussed. The research results showed that: 1) The Kunlun-Huanghe Movement might affect the middle and lower reaches of the Yangtze River and result in the activations of regional faults and larger regional block uplift movements on the northern piedmont of the Huangshan Mountain. This regional uplift further provided the downcutting driving force and thus drove the development of the Qingyijiang River. Therefore, the regional tectonic responses to the Kunlun-Huanghe Movement might drive the development of the Qingyijiang River; 2) The East Asian summer monsoon experienced two significant stepwise weakening events at approximately 1.3 Ma and approximately 0.9 Ma which led to the remarkable increase of regional precipitation within the study area. This increase of regional rainfall further provided the incision media and sustained water, and finally initiated the development of the Qingyijiang River. Therefore, the stepwise weakening events of the East Asian summer monsoon might control the development age of the Qingyijiang River; 3) Both the development of the Qingyijiang River and the channelization of the Yangtze River might be a combined result of the regional tectonic responses to the Kunlun-Huanghe movement and the stepwise weakening events of the East Asian summer monsoon intensity. In addition, a new local base level of erosion served by the Yangtze River after its channelization might also promote the development of the Qingyijiang River. Therefore, the development age of the Qingyijiang River which could reflect the channelization age of the Yangtze River to a certain degree supported the viewpoint that the Yangtze River had been established during the period from the late Early Pleistocene to the early Middle Pleistocene. This study provides a case and reference for the studies of the small and medium river development in the Eastern monsoon area of China.

Blowouts are depressions produced by wind erosion, which occur on sandy coasts or lake shores and sandy grasslands in arid and semi-arid rergions. Topographic steering changes the velocity and direction of airflow within the blowout. Then a local difference in sediment transport exists, which changes the pattern of erosion and accumulation and reforms the morphology of the blowout. Topographic changing reacts on the near-surface airflow and forms the feedback and response mechanism between morphology and dynamics. This article briefly reviews the processes of morphodynamic and evolvement of blowouts, and analyzes its study trends, hoping to provide some reference for similar researches in the future. Although lots of progresses have been made in study of dynamic and evolvement of blowout, there are still many aspects need to be improved. First of all, airflow patterns in blowout are complicated, because of the limited field data, we often get an unreal construction and a poor understanding of airflow patterns. In order to aquire more sufficient field data and precise analysis, more intense observation sites and continuous observations are needed. Secondly, temporal and spatial scales of previous researches in blowout are relatively small. Most of the research just focused on the dynamics and evolvement of individual blowout, but ignored the others’ in the same region; and limited observations to the current developmental situation, but ignored the processes or morphology in the past and future. In order to summarize a relatively complete evolutionary pattern of blowouts tentatively, the large-scale and long-term monitorings to the blowouts, which in variety of developmental phases are requisite. At last, compared with foreign researches which made certain achievements in coastal blowouts, domestic researches in evolutionary processes of inland blowouts which developed in different conditions and different genesises are deficient. Many blowouts which in various developmental phases occurred in arid and semi-arid regions in north China, evolutional laws could be summarized according to their conditions and morphological characteristics. Then make comparisons with relevant research results of coastal blowouts, and validate their applicability in terrestrial environments.

Under the background of global climate change, extreme events occur frequently which can cause intensified natural disaster risk. China characterized with high population density and intensive economy in east-central areas, as one of the countries influenced frequently by typhoon events, the agriculture, population, buildings and economy are threatened significantly by typhoon disasters. The quantitative risk assessment on disaster-bearing bodies and regionally integrated zoning are not just a theory study in risk management, also can offer practical guidance on mitigation and prevention in typhoon disaster. In our study, on the basis of the typhoon disaster mechanism, the vulnerabilities of disaster-bearing bodies were evaluated according to typhoon disaster loss criteria established by applying historical typhoon loss data. In addition, the probabilities of typhoons in each country region were analyzed comprehensively using the indices of landing frequencies and track line lengths. Then applying risk assessment model, the typhoon risks caused by the different intensities were evaluated quantitatively. Synthesized on the risks of the same or the different intensity typhoons for disaster-bearing bodies, the typhoon disaster risk zone for China was divided into nine areas and belonged to three classes (respectively is high, medium and low risk). The high risk areas are located in southern part of Guangxi Province, most of Guangdong Province, coastal areas of Fujian and Zhejiang Province, Yangtz River Delta area, most of Jiangsu Province, some inland counties of Jiangxi and Anhui Province. Based on the above results, the helpful suggestions on prevention and reduction in regional typhoon disaster were put forward.

Reasons of serious drought in eight cities and provinces of Northern China in 1942 were analyzed. Results indicated that there is an extreme arid event occurred in 1942 and centering on Henan Province, which occurred under a relatively warm background. The arid event was the most serious during the summer and winter. The warm sea temperature of Pacific Ocean during 1942 was the most important sea background of this extreme arid event was, while the negative phase of South Oscillation during 1940-1942 was the most outstanding circulation environment of this extreme arid event. In addition, the El Nino event with the intensity of 1 level, the weaker East Asian summer monsoon, and the less landing typhoon than the other years possibly could be the main reasons inducing to this extreme arid event in 1942 over the north China. Because Henan Province is the climatic change sensitive area and the ecological environment frail area, the earlier period dry waterlogging disaster frequency sends, in addition the multi-disasters were in the past concurrent, caused Henan Province's drought to be most serious in 1942.

Biodiversity is the material foundation and the environment guarantee that people are taken for their survival and development, and has four levels: molecular, species, ecosystem and landscape. The identification and understanding of the spatiotemporal variation of biodiversity in the landscape level are not just an important part of regional biodiversity monitoring and assessment, but also the first step in the formulation and implementation of the protection scheme. The Bailong River Watershed of the Gansu Province (BRWGP), one of the most abundant biodiversity regions in China, locating in the transitional ecotone along the Tibetan Plateau, Loess Plateau, and Qinba Mountains. The BRWGP served as a case to analyze the spatiotemporal heterogeneity of biodiversity. Based on the data integration analysis platforms of RS, GIS technology and InVEST 2.5.6, a comprehensive index system of biodiversity spatial patterns constructed with the incorporation of habitat quality, vegetation net primary productivity, and landscape state index by considering the difference of three assessment indicators intensity and influence degree. Meanwhile, AHP was used to determine the weights of index and GIS spatial technology apply to analyze the spatial distribution and differentiation of biodiversity under the landscape geography perspective. Our goal went to revise the biodiversity evaluation module of the InVEST model and demonstrate biodiversity spatial patterns on a grid cell. The results indicated that biodiversity was high and had obvious spatial pattern variations in the BRWGP. Areas with higher biodiversity mainly distribute in the national nature reserve and forest, while the relatively poor biodiversity areas distribute in the valleys of the BRWGP between Zhouqu-Wudu-Wenxian, the valley of Minjiang in Tanchang County, alpine mountain snow regions, and bare rock zones. Moderate biodiversity areas appeared in agroforestry ecosystem, shrub and grassland, which a vegetation cover, species richness and habitat quality were general. In 1990-2010, biodiversity was high and increasing, the area proportion of higher biodiversity (critical areas) increased from 16.74% to 26.02%. Meanwhile, the high growth area of biodiversity change was concentrated in the ecological engineering zone and forest districts (Such as these forest districts of Duoer, Axia, the Minshan Mountain, Baishuijiang Nature Reserve), while biodiversity reduction area locates in the region of human activities intensively and frequently, such as cultivated area, urban and rural areas.

The in-depth implementation of the new urbanization and rural revitalization strategy has pushed the urban-rural relationship into a new stage of integrated development. Based on Citespace1.0 software analysis and literature induction method, the paper identified the research hotspots of urban-rural relationship, reviewed the research progress of urban-rural relationship. Which included theoretical connotation and influencing factors of urban-rural relationship, measurement and evaluation of urban-rural connection, urban-rural spatial organization and development mode, and coordinated development of urban-rural areas and promotion strategy. Combining with the social economic background of information revolution and the change of urban-rural relationship in China, we points out that the construction of urban-rural relationship in the new period needs to change the traditional urban-rural relationship centered on the city, promote the integration of urban and rural areas and the formation of a new pattern of equal development between urban and rural areas. Based on this, we puts forward and discusses the construction and overall thought of a new urban-rural relationship toward urban-rural integration development. Then we proposes a framework for urban-rural integration analysis based on elements flow, puts forward the general idea of analyzing the characteristics, pattern and mechanism of urban-rural elements flow, which is supported by flow space theory and new mobility paradigm, multi-source data and visual analysis. The paper emphasizes the importance of measurement and evaluation of urban-rural relationship and the flow of urban-rural elements. The characteristics, pattern and mechanism of urban-rural factors flow, and the regulation and control strategy of the integration development of urban-rural areas are discussed in detail. The paper also explores the construction of the urban-rural integration database, the measurement of the flow of urban-rural elements and their spatial-temporal changes, and spatial simulation and visualization expression and other methods and techniques.

Forest is a main component of the terrestrial ecosystem, and its monitoring is the vital support for sustainable utilization of forest and global change researches. The home and aboard progress of remote sensing techniques application on monitoring forest ecosystems was concluded in this paper from four respects: classification and changes detection, the retrieval of vital ecological parameters of forest ecosystems including tree height, leaf area index, canopy density, etc., the estimation of stand volume and biomass, and disturbance monitoring. After summarized remote sensing data and models used in forest ecosystems monitoring, research prospect of establishment of integrated forest ecosystems monitoring platform with multi-dimension, multi-scale and high time density were put forward, which synthesized filed data, land-to-air high-resolution radar scanning techniques, multi-source optical remote sensing modeling and process models.

The black soil region in Northeast China is one of the world’s four black soil regions. It is well known for its high organic matter content and high fertility. It is not only the basis for the development of agriculture in Northeast China, but also the granary of China, which plays a decisive role in safeguarding the national food security. According to the characteristics and problems of black soil in Northeast China, this review first elucidates the forming conditions of the black soil and the natural characteristics. Secondly, we describe the evolution of soil properties and fertility in the process of the reclamation of black soil. The soil organic matter content and soil fertility decreased significantly, which have severely affected the sustainable development of agriculture in black soil region in Northeastern China. Besed on this analysis, different protection pathways and their controlling mechanisms on soil fertility are analyzed. Future research on black soil should be emphasized on the development of new technologies, new methods, and cross-disciplinary theories to ascertain the evolutional characteristics of soil fertility and their influencing factors. It is necessary to cultivate high-yield, high-quality crop varieties that are more suitable for the climatic conditions in Northeast China, to optimize the cropping system in combination with the current technological regulation pattern in this region, to improve the quality and yield of crops, to increase the overall productivity and competitiveness of agriculture soil, and finally to ensure the sustainable use of agriculture in the black soil region.

It is noted that the climate change is not globally uniform. Regional variations can be much larger and considerable spatial and temporal variations may exist among climatically different regions. In addition, climate change in a specific region or nation is of particular interest to that region and its economic activity. Archival meteorological data of monthly air temperature and precipitation series were used to investigate climate change trends and characteristics in 1951-2010 of Kunming, which is located in the low-latitude plateau region of southwest China. The magnitude of a trend was estimated using linear regression analysis and the station significance of a trend was assessed by the M-K test and MT-test. Furthermore, the periodicity of a series was probed by Morlet wavelet transform. The results show that the climate change presents increasing air temperature and decreasing precipitation in the past 60 years in Kunming region. The annual mean temperature increased at the trend rate of 0.24℃/10 a at the significance level α= 0.01. The annual precipitation decreased at the rate of 3.89 mm/10 a. The increasing trend of air temperature is more obvious in dry season than rainy season, but decline rate of precipitation is obvious in rainy season than dry season. In the first 10 years of 21st century , Kunming experienced much more severe temperature increase and precipitation decrease than in other periods over the observation period of 60 years. In addition, annual mean temperature of Kunming exits two evident characteristic time scale with 5-10 years and 10-15 years. The periodic variations of annual precipitation time series are localized in 10-15 years.

Based on the daily NECP /NCAR reanalysis data of 500 hPa height field from 1948 to 2009, an objective classification and widely-agreed method was applied to analyze the temporal and spatial distributions of atmospheric blockings high in Asia during summer,In addition, the location and numbers of blockings high was automatically determined. The results show that there are 1 337 blocking events during the last 62 summers. According to the active period of blocking events, a period of 3-7 days are dominant during all the events which account for 80.1%. Based on the accumulative numbers and days, the blockings are divided into eastward type (blocking high over the Okhotsk Sea), westward type (blocking high over Ural Mountain), central type (blocking high over Baikal Lake) and the others, totally four types, occupying at 27.5%, 30.4%, 18.3%, and 23.8 %, respectively. Since 1990s, blocking events in Ural region are in a weak period, otherwise in Okhotsk region are in a strong period ,but blocking events in Ural region begin taking upward trend at the beginning of 21^st century. Bblockings in Okhotsk region take a clear downward trend. There is a significant positive relationship between blocking events and cold vortex in Northeast China, but a negative correlation between blocking events and temperature of Changchun and Harbin in summer. Blocking high is one of important circulation system which causes the low temperature in Northeast of China in summer. During westward type blocking events strongly active years in June, a strong easterlies air flow in 850 hPa is found over the region of 20°E -140°E, 40°N -55°N, It is advantageous for cold air come from the northeast path in Okhotsk region to invade Northeast Asia and the northeast area in China.

The formation and enlarging of economic development gaps between the east, centre and west in China resulted from long time evolution by comprehensive effects consisting of historical, natural and social factors. Contemporary unbalance of regional economic development enlarges the gap of economic grades in the three parts of China. It is a good way for the western China to carry out the strategy of overall opening to outside world, but it should emphasize to connect with the Pacific Area and the eastern and central parts of China. Meantime, it is not negligent for the western part to accelerate the construction of trafic trunk connecting the west with the east.

In recent years, slope units have been widely utilized in landslide susceptibility mapping and geological hazard assessment. Slope units automatically derived from high-quality DTMs, partition the territory into hydrological regions between drainage and divide lines. The division method of slope units conducts subwatershed segmentation on elevation and the reversal to extract ridge lines and valley lines, then overlays these terrain feature lines. However, these resultant units are unable to match with geomorphology background where intermountain basins or large open valleys exist. In this article, according to the basic morphometic system of elevation and the derived variables, slope is derivative of elevation while curvature is that of slope, thus the break of slope should be indicated by curvature instead of elevation. The disability of indicating variation of slope is regarded as the main reason for the limitation in the conventional method. According to the theory of watershed segmentation of mean curvature, the division method of slope units is improved by overlaying watershed boundaries on curvature and the reversal in ArcGIS. Firstly, the DEM should be smoothed twice with a 5×5 average filter in order to reduce the effect of noise and small scale variation in the DEM. The curvature is then calculated from the filtered DEM using the Arctool named Curvature. After that, watershed boundaries are generated mainly through computing flow direction, scouting sink and dividing watershed in the curvature image, and this image should be reversed for watershed boundaries on the reversal curvature. Finally, slope units can be separated from each other by these two kinds of boundaries which are further combined into the boundaries of slope units. Giving an example from Huachi County of Gansu Province, elevation layer in the resolution of 20 m was used as input data, and both two methods were then applied for slope unit division. Compared with the conventional method, the revised approach not only uses ridge lines and valley lines to segment slope units, but also utilizes tableland boundaries and open valley boundaries to separate horizontal surface from the inclined. The revised approach may give a new definition that slope units should be divided by ridge lines, valley lines, tableland boundaries and open valley boundaries. Also the revised method utilizes watershed segmentation on curvature instead of subwatershed division on DEM where filling sinks perhaps causes the serious change of reversal elevation. Furthermore, the resultant units have relatively uniform size and shape, more than 80% of them with the area from 0.1×10⁴ to 6×10⁴m² and about 60% between circle and triangle shape, which are more suitable for landslide hazard evaluation. It is worth mentioning that the revised method would be more competitive than the original in some regions with large area of horizontal surface, just like Loess Tableland and reservoir surface.

The Northeast is a complete and independent geographical and cultural region in northern China. Since the founding of the People's Republic of China(1949), the administrative division pattern in Northeast China has changed a lot. The administrative division adjustment is mainly divided into the following five stages: In 1949-1955, the provincial-level administrative districts were adjusted frequently. In 1955-1969, the provincial-level administrative district was stable, the prefecture level and county-level administrative districts were frequently split and merged. In 1969-1979, the eastern region of Inner Mongolia was allocated to the three provinces (Liaoning, Jilin and Heilongjiang) of Northeast China; In 1979-1996, the prefecture-level and county-level administrative districts were adjusted frequently. Many counties changed to cities and municipal districts. From 1997 to the present, this stage was relatively stable, administrative divisions were adjusted less. The counties and cities were mainly changed to municipal districts. Factors such as the level of economic development, traffic conditions, history and culture, physical geography conditions, and policies or standards have had important impact on the pattern and adjustment of administrative divisions in the Northeast China. Finally, the article analyzes the main problems of the administrative divisions in Northeast China, and proposes the optimization path of administrative division adjustment. The authors put forward the following suggestions: At the provincial level, four prefecture-level cities in eastern Inner Mongolia will be built separately and named Xing'an Province. At the prefecture-level, the Jiagedaqi and Songling District will be placed under the Daxinganling Area, and chang the Daxinganling Area to a prefecture-level city. At the county level, the counties and the mega-towns with good development conditions will be changed to county-level cities for increasing the number of small cities. At the township level, continuing to promote the "township merger", and townships around the big city will be changed to street offices.

How to evaluate the impacts of urban public resources and facilities on the price of real estates has been the research topic in academic circles for a long time. Relative to the other urban public facilities such as subway stations or rail transit, large-scale parks and greenbelt, landscape water, universities or key primary and middle schools and so on, the relationship between hospital and housing prices has not caused enough attention. In this article 7 Class 3A comprehensive hospitals in Shanghai urban central areas were selected, using the Hedonic price model and multiple regression analysis method, to conduct an empirical analysis of the spatial effect of these hospitals on residential property prices. The results show as follows: 1) Generally speaking, compared to other environmental factors, the less impacts of Class 3A comprehensive hospitals were corducted on the surrounding residential property prices, and the factors such as building area, property management fees, school-nearby houses, rail transit, height of buildings, the distance to the CBD have greater influence on housing prices. 2) Class 3A comprehensive hospitals have a negative impact on the surrounding residential property prices. And in the same circumstances, as shortening the distance of houses to the hospital each 50 m, the average housing price fell 0.602%. 3) Because of the different location and distance to the CBD of Class 3A comprehensive hospitals, there is a spatial differencine in their impact on housing prices. In general, the closer distance to CBD is, the less negative influence housing price is affected by the hospital.

The response of structure and function of terrestrial ecosystem to global climate change has become a major point. Vegetation is an essential component of the terrestrial ecosystem which has proved to be sensitive to climate change. Normalized Difference Vegetation Index (NDVI) is widely recognized as a good indicator of vegetation coverage and productivity, has been widely used to indicate vegetation activity and dynamics, also vegetation growth, ecosystem structure and functions respond to climate change. Climate warming has important influence on the vegetation coverage, and alpine grassland is one of the most significant vegetation type on the Qinghai-Tibet Plateau. This study used GIMMS NDVI data sets and climate data from 40 meteorological stations to investigate spatial and temporal variations of alpine grassland cover and the response of NDVI to climatic variables on the Qinghai-Tibet Plateau in 1982-2013. The results showed that the average growing season NDVI is high in the southeast and low in the northwest. As a whole, the alpine grassland cover tended to increase on the Qinghai-Tibet Plateau, with the rate of 0.000 3/a (p<0.05) in the past 32 years. Spatially, the tendency of alpine grassland NDVI showed great heterogeneity, with the significantly NDVI increased mainly distributed in the northeastern part of Qinghai-Tibet Plateau dominated by alpine meadow which approximates to 26.0% (p<0.05) of the total study area. The area with significantly decreased area accounted for 4.7%, mainly emerged in the western part where the grassland was dominated by alpine steppe. In the regional scale, the variation in alpine grassland cover was more closely related to precipitation than other climate factors. The spatial characteristics of the relationship between growing season NDVI and climatic variables were analyzed based on the eco-geographical regions. Significant lagged correlations between precipitation and seasonal NDVI were found for the alpine steppe. The results suggested that precipitation was the key limit variable in the northeastern part of Qinghai-Tibet Plateau with higher annual mean temperature. But in the eastern and central eco-regions with the more rainfall, temperature could limit the growth of grassland vegetation. In the southern plateau with more precipitation and higher temperature compared with other regions, the correlations between alpine grassland cover and climatic factors were significant positive. The change of alpine grassland cover was not significantly relevant to climatic variables in the middle and western part of Qinghai-Tibet Plateau.

After the financial crisis in 2008, a new phenomenon “shrinkage” has appeared in Dongguan’s urban area, which manifested population size reducing in its towns. Although the economic recovery rapidly in the post-crisis period, the spatial separation of population growth and shrinkage is aggravating, accompanied by a series of changes in the demographic structure. Base on the perspective of demographic change, this article makes an in-depth analysis of the growth and shrinkage in Dongguan by using the Social Security Registration data. We summarize the characteristic of demographic changes in the size, age, gender and education after the financial crisis, and industrial economic structure of different towns. Moreover, we construct a panel regression model for exploring the factors and mechanisms that affect urban population growth and shrinkage. The result shows: 1) While the population size of Dongguan tends to growing in fluctuation, the population structure shows trends for migrant population localization, male and female more imbalance, younger and highly educated population. 2) Advanced manufacturing and modern service industries to promote city growing, and outward processing and manufacturing transformation failure will affect the city shrinking. 3) The spatial distribution shows the "growing in the north, shrinking in the south", forming a concentrated area where the central area growing, the northwest area and the southeastern area are shrinking. 4) Macroeconomic fluctuation, industrial transformation, technological innovation inputs and local development pathway have significant impacts on demographic growth and shrinkage in Dongguan.

The study is based on the maximum value composite MODIS NDVI data of growing seasons (GNDVI) from 2000 to 2020 in the Three River Headwater Region (TRHR). It uses trend analysis and spatial analysis methods to quantify changes in grassland greenness in the region. Additionally, correlation and partial correlation analyses are applied to explore the relationship between temperature, precipitation, and GNDVI at different temporal and spatial scales. The results of the study show that: 1) From 2000 to 2020, the overall trend of grassland GNDVI in the TRHR has increased, with 77.53% of pixels showing an increasing trend. Among these, 33.95% of pixels show a significant increase (P<0.1). On the other hand, a decrease is observed in some areas, with 22.47% of pixels showing a decreasing trend, and 3.03% of these showing a significant decrease (P<0.1). 2) The pixels with a significant increase in GNDVI are mainly found at elevations of 4500-5000 m and on north-facing slopes with a gradient of 2°-6°. Conversely, the pixels with a significant decrease in GNDVI are primarily located at elevations of 4500-5000 m and on south-facing slopes with a gradient of 6°-15°. 3) Overall, in the TRHR, GNDVI shows the strongest correlation with temperature and precipitation during the growing season. The correlation with the minimum temperature during the growing season (R=0.79, P<0.001) is stronger than with precipitation (R=0.66, P<0.001) and average temperature (R=0.55, P<0.001). The relationship between monthly climate factors at the grid scale and GNDVI shows that the interannual fluctuations of GNDVI are most strongly correlated with precipitation and minimum temperature in July. Spatially, the eastern GNDVI is primarily influenced by precipitation, while the western GNDVI is mainly driven by temperature.

：Intangible cultural heritage is defined as a spectral cultural heritage that has important historical and art values. Research on the geographical distribution and affecting factors of the intangible cultural heritage in China is important for the improvement of heritage protection and management. Data from 2 376 items concerning intangible cultural heritage in China are collected on a national level and analyzed based on the Geographic Information System. Research shows that the structural types of intangible cultural heritage in China can be divided into three classes. The first class includes traditional craft and traditional opera. This class is considered the most predominant class among the intangible cultural heritage classes in China. The second class, which is less predominant, includes traditional music, customs, dancing, art, and literature. The third class, which is the least predominant among the classes, includes traditional physical education, medicine, and drama. Numerous types of intangible cultural heritage exist in China that were influenced by the nationality and rationality of the population. Most of these types of heritage can be found in the rich history, popular culture, and minority regions of China. The structural level of the heritage is unbalanced and exhibits zone and block shapes. The intangible cultural heritage in China is mainly distributed in the Eastern and Middle regions, whereas only a few are distributed in the Western region. The number and density of intangible cultural heritage in Southern China are bigger than that in Northern China. Intangible cultural heritage in China is also preserved by communities along the Changjiang River. Heritage distribution has a certain correlation with big river systems. The number and density of intangible cultural heritage is greatly unbalanced in the Eastern, Middle, and Western regions of China. Eastern China has the highest density of intangible cultural heritage followed by Middle China and Western China. Intangible cultural heritage is highly dense in Eastern China and sparse in Western China. The factors that affect the distribution of intangible cultural heritage are as follows. First is the geographic environment. More intangible cultural heritage can be found in areas rich in products and human activities. Second, the distribution of intangible cultural heritage has certain correlations with livable environmental conditions and minority regions because these areas are characterized by long histories and rich cultures. Third, minority regions along border areas are subjected to less cultural invasion. Although intangible cultural heritage items are divided in this paper to assess their precise spatial distributions, distinguishing these items is difficult because of carrier movement. The evaluation of intangible cultural heritage by the National Cultural Relics Administration is also limited. Thus, research on evaluation of intangible cultural heritage should be reinforced in the future.

Base on the data of daily precipitation of 58 meteorological stations in Loess Plateau Region, the temporal and spatial variations of different precipitation phases were analyzed in Loess Plateau Region. The results show that line of 35°N is the delimitation boundary of main snow region and rain region; the region to the north of 35°N is the snow region, the region to the south of 35°N and to the east of 110°E is main rain region. Besides, along the 35°N and 110°E, the sleet occurs frequently. The rains in Loess Plateau Area have obvious and different inter-annual fluctuations, but the snow is not very obvious. Except rain and snow, the fluctuation frequencies of sleet, fog (dew, frost) were weak and tend to the same. The station-days of all these recipitation phases (rain sleet fog dew frost) have remarkable 30 a periods. Besides, there were also 5 a, 10 a and quasi 15 a periods to different precipitation phases.

China-US relations have always been the most important part of international geopolitical relations. Discovering and analyzing of the attitude of two sides to each other from an international multilateral perspective is of great significance for understanding the internal causes of variations in China-US geopolitical relations. Due to differences in political systems, the analysis of characteristics of the China-US changes from the perspective of the presidency of the U.S. can provide a deeper knowledge of the international geopolitical tendencies. From the time series analysis of China-US relations, we can understand the evolutionary stages of China-US geopolitical relations. An in-depth analysis of the motives of China-US relations changes is of great significance for properly making international geo-strategies. Based on the GDELT data, this paper utilized probability analysis and adaptive fractal analysis methods to analyze the attitudes' differences between China and the U.S. during the US presidential terms since 1979 from the perspectives of cooperation and conflict. Moreover, the persistence of China-US attitudes since the establishment of diplomatic ties was also studied. The results show that: 1) China-US geopolitical relations have experienced three periods: the Cold War period, the transition period and the economic and trade cooperation period. The characteristics of these three periods are that the strategic basis of China-US relations has changed from a joint anti-Soviet to economic and trade relations. 2) The negative attitude of the US toward China developed and improved during the George H.W. Bush and Clinton periods. It eased during the George W. Bush era and the early Obama period, but it became more serious in the later period of Obama. 3) The overall attitude of US toward China persists for about 4 years, and is mainly influenced by negative attitudes. During the current Trump administration, the political and economic factors of China-US geopolitical relations have undergone major transitions. It is recommended that policy-makers and researchers of China-US relations should pay attention to this transformation and seek new thoughts and new pathways to cope with China-US relations in a new stage.