Information and communication technologies (ICT) is a major symbol of the contemporary world, which is predominated by two interwoven tendencies, namely globalization and informatization. It is now widely accepted that the world is moving fast towards an information age, while ICT is a major channel to such a historical transformation. Indeed, no technological progress in the last several decades can match the advent of ICT in terms of its profound and extensive influences. Since 1994, the development of ICT in China has been incredibly fast, but there has been “digital divide” between provinces. Indeed, there are huge digital-divide worldwide, which would impact economic spatial distribution. It is against such a background that this article takes a close examination on the development of informatization in China and its spatio-temporal pattern. Based on the literature review, principal components analysis and fuzzy analytic hierarchy process, it established ICT development index (IDI) and then calculated IDI and CV value, in order to provide a more comprehensive explanation of ICTs trends and developments. It also tried to gauge and justify the spatial implications of ICTs development, especially the relationship between informatization and economic development, by regression analysis. The findings of this study are follows. First, there are significant regional differences in informatization, and the development of ICT declines gradually from Eastern China to Western China. From 2000 to 2010, the development of ICT in Western China and Central China are much faster than Eastern China and Northeast China, while the regional digital gap is becoming smaller. Secondly, the difference of informatization among provinces is also very remarkable. The provincial spatial pattern of informatization has changed, with lessened digital divide in 2000-2010. Finally, at provincial scale, the spatial distribution of ICT has obviously positive correlation with local GDP development. From 2000 to 2010, with the evolution towards an informatization society, the relationship between informatization and economic development has been more and more related.
城市化与碳排放是当今世界研究的两大焦点,两者的结合点——城市化对碳排放的影响更是研究的重点。利用全球主要国家（地区）历史数据,根据城市化水平划分不同的组别,考察城市化动态演进阶段与碳排放之间的相关性,并通过STIRPAT模型评估不同城市化阶段各因子对碳排放的影响;结合城市化发展阶段各要素的特征,探讨不同阶段城市化对碳排放的影响。结果表明,城市化对碳排放的影响表现为驱动和制动双重作用：① 当城市化发展处于初期阶段时,城市系统发展缓慢,驱动与制动作用均不明显,碳排放缓慢增长;② 当城市化发展处于中期阶段时,城市系统进入加速发展阶段,驱动作用逐渐占主导,制动作用较小,碳排放迅速增长;③ 当城市化发展处于后期阶段,驱动作用仍然占主导地位,但制动作用逐渐增强,碳排放速度有所减缓,排放总量仍然增加。
Urbanization and carbon emissions have attracted intensively attention. This article analyzes the impacts of the urbanization on CO2 emissions in three aspects. Then the historical data of 76 countries (regions) (1980-2007) are employed by separating them into different categories according to urbanization levels to study the correlation between the stage of urbanization and the dynamic evolution of the CO2 emissions. The main impact factors on CO2 emissions during different stages of urbanization are evaluated based on the STIRPAT model. Finally, according to analysis results, combined with the characteristics of the various elements in the development stage of urbanization, this study explores the impacts of various stages of urbanization on CO2 emissions. The results showed that: the urbanization affects the CO2 emissions mainly through changing lifestyle, production and land use, which performances a driving and restricting role. In the early stage of urbanization, the driving and restricting effect of the CO2 emissions are not obvious, showing slow development in urban system and the slow growing carbon emissions rate; in the mid-stage, the driving role of urbanization on CO2 emissions becomes to be dominant, but the restricting effect is weaker, which is characterized by the acceleration development of urbanization system, the city development in numbers and scales, the accelerated industrialization process, and a rapid growth of CO2 emissions; in latter stage, the city enters a slow phase of development, urbanization on the driving role of CO2 emissions is still dominant, but the restricting effect is gradually enhancing. In this stage, the quality of urbanization continuously improves, and household consumption reaches a high level. Meanwhile, the phenomenon of suburban urbanization and counter urbanization appear, the tertiary industry takes up most part of industrial structure, technical level increases rapidly, CO2 emissions becomes slow, but the total emissions are still increasing. Therefore, the impact of urbanization on CO2 emissions is different in various urbanization stages. In response to CO2 emission reduction mandate in the context of global climate change, countries (regions) should reasonably guide the process of urbanization and enhance the restricting effect of urbanization.
采用层次分析法和模糊集方法,以浙江省为研究区,构造一种能刻画地理影响程度的空间异质性的地理空间,修正克鲁格曼城市体系模型的均质空间假设,以期观察城市体系模型在经济和地理环境下的不同表现。模拟结果显示： 地理环境对模拟城市数目的波动具有持续、稳定的推动效应,但波动幅度不大,说明即使存在外生差异,城市体系演化仍旧主要靠经济系统的内生力量。 在经济或地理环境下,模拟城市的空间分布具有均衡结构,均呈现近乎对称的六边形格局。但纳入地理环境,能明显提高模拟结果与实际结果的吻合程度。 在地理环境下,4种权重模式的模拟结果各不相同。其中模拟城市的空间分布对经济权重占优模式的反应结果与真实环境比较一致,说明经济地理因素对浙江城市体系演化有较大的影响。
To modify the assumed homogenerous space in the urban system model as developed by Krugman (1993), this article uses the fuzzy set theroy, together with the analytic hierarchy process (AHP) approach, and constructs a series of geographic spaces with spatial heterogeneity based on the study case on Zhejiang Province, aimed at examining the importance of economic or geographic features as determinants of the size, number, and location of cities in this province. The simulation of the Krugman’s urban system model shows geographic features indeed play an important role in the simulated broad patterns in the spatial distribution of the Zhejiang’s cities, but the urban systems in the study area evolves primarly because of economic geography features, concisely speaking, the interaction between transport costs and plant-level scale economies. After controling for other parameters, this model might predict more cities in this study case when transportation costs are higher, a share of the manufacturing sector is lower, or the elasticity of substituion is higher. Moreover, in equilibrium, the predicted cities can be found to be located according to a spaital distribution of the hexagonal lattice with the realistic economic as well as geographical enviroments. If true geography is incorporated into the model, the assumed space offers better simulating environments, and, as a consequentce, will improve the proformance behavior of the Krugman’s urban system model. The simulated patterns of city distribution can be postulated by one variant of central place theory proposed by Water Christaller (1966). Furthermore, under the surroundings of dispersed scenarios of four weights, an initial advantage in geography over all regions comes into effect leading to a variety of spatial patterns of urban system simulation in this province. Among them, for the Zhejiang urban system as a whole, cities are distributed consistent fully with those observed when these locations have a certain advantage of economic geography over the others. This might suggest that economic geography effects may dominate dynamic process of urban system development over time across space implying that high market potential might be associated with the predicted cities in this study area.
Following the acceleration of the economic globalization, marine transportation has become the main way of international goods trade. As a result, the port becomes an important influence factor of the economic development which causes more attention concern. In the study, the Huff model was employed to calculate the potential-energy value of the influence which the six ports along the Liaoning coast act on the hinterland city. Then, a quantitative estimate about the spatial evolution process of the port hinterland along the Liaoning coast was performed in 1995-2009. Finally, we qualitative analyzed the driving factors of spatial evolution of the port hinterland. The result showed that: 1) The spatial distribution of the port hinterland in the study area has changed a lot during the past 15 years and the study area has been changed from the single hinterland of Dalian port to a mixed-hinterland of several ports. The hinterland ever belonged to Dalian port along the traffic line between Harbin and Dalian has converted to the hinterland of Yingkou port which caused a decrease on the extent of hinterland in Dalian port and oppositely an increase on the extent of hinterland in Yingkou port. Some local ports (such as Jinzhou port and Dandong port) mainly serving for the surrounding hinterland cities has not experienced a significantly variation on the extent of hinterland. 2) Based on the calculation result of the Huff model, the influence potential-energy value of the six ports has also changed. According the potential-energy value, the influence of Dalian port on the study area decreased in the past years, especially the influence on Liaoning Province and surrounding areas which has experienced an obviously reduction. The Yingkou port has an increased influence along and both sides of the T-shaped traffic line, which make the Yingkou port a more and more important position among the six ports. The influence of Jinzhou port on its original hinterland has become more stable than past years. In addition, there is an expanding trend on the spatial extent of Jinzhou hinterland toward to the central parts of Liaoning Province which represents a rising influence force of Jinzhou port. The Dandong port also has an increased influence on the most parts of the study area, particularly on the middle and eastern area of Northeast China. Following the improving of port infrastructure construction, Dandong port has become a new thoroughfare to the Sea of Northeast China. 3) The influence factors of the hinterland spatial evolution are various and complex. According to the qualitative analysis of the driving factors which caused the spatial structure evolution of the port hinterland along the Liaoning coast, location conditions, transportation infrastructure conditions, the rising of urban influence force and the guidance of government policies are considered as the most important factors.
The globalization is far from the displace process. However, it is the process of redefination and production of locality. On the background of globalization, the frequent migration of people and businesses makes them exceed the established boundary, forming a more and more translocality. Recently, the locality and cultural production are gotten a lot of research interests of cultural geographers. However, many questions, such as ‘paradox of cultural preservation and innovation’ and the ‘dilemma of authenticity and standardization’ faced by translocal cultural production are unresolved by scholars. This article constructs a theoretical framework of restaurants' cultural production to discuss the categories and characteristics of translocal cultural production based on four cases of foreign restaurants in Canton. The theoretical analysis reveals that there are four different kinds of cultural production of translocal restaurants: standardization of authenticity, cultural production of authenticity, cultural production of standardization, and cultural production of Heterogeneity. And the results of case study illustrate that four kinds of cultural production can be accepted by the consumers of translocal restaurants. In virtue of disciplinary integration, the conbination of translocality and cultural production would provide chances for the development of translocal cultural production. And also, it is a new exploration of the food geography with the methodology of new culture geography. This article would promote the discipline development of cultural geography. In the meanwhile, it can provide a theoretical basis for the protection and innovation of food culture, as well as diffusion of food culture and identification of place image.?
集成青海东部考古数据和DEM,利用面积和墓葬相结合的估算法计算了区域史前人口数量,并利用GIS工具重建史前区域耕地面积的时空格局。结果表明：新石器马家窑文化时期区域人口、耕地迅速增加,并在晚期马厂时期达到新石器的顶峰,人口总数接近4万人,耕地面积达到462 km2,人口和耕地主要分布在黄河—湟水谷地内;齐家时期人口和耕地有一定幅度下降,在青铜时代人口和耕地有显著回升和增长,人口总数达61 000余人,耕地面积达到1 076 km2,约占区域适宜耕地总数的1/10。伴随人口与耕地的变化,人类活动的环境效应也逐步显现,5~4 ka B.P.人类活动导致研究区河谷地带乔木的减少,伴人植物增加,尤其是禾本科含量有较大幅度增加,与当时的粟作农业关系密切;4 ka B.P.后大范围的乔木减少是气候变化结果,其后人类活动加强,加速了乔木覆被面积的萎缩。
Integrated the archaeological and DEM data in the eastern Qinghai Province, using a combination of the area archaeological site and burials to estimate the regional prehistoric population, and apply the GIS tools to rebuild the regional cultivated land area of ??the prehistoric period for time and space. The results showed that regional population and cultivated land increased rapidly during the Majiayao culture of Neolithic Period, and the population had reached the peak during the late Machang culture regional of Neolithic period,in which the population had totally risen up to about 40×103 and the size of farm land was expanded to ??462 km2. The population and the farm land were mainly distributed in the valley area of the Huanghe River-Huangshui River. The population and farm land were decreased significantly during the Qijia culture period, but it was rebounded obviously during the bronze age, in which total population increased to 61 000 and the farm land was expanded to 1 076 km2, about 1/10 of the total arable land area in the region. With the changes of population and farm land, the influence of human activities on the environment began to appear. In 5-4ka B.P., human activities lead to the reduction of the arbor in the study area, the increase of Androphile, especially Gramineae have sharply increased, as agriculture is closely related with the millet. After 4 ka B.P., a shape reduce of the arbor is due to the change of climate, while strengthening of human activities accelerated the shrinking arbor cover area.
以内蒙古希拉穆仁草原旅游地为研究区,以2000年、2004年、2007年和2009年遥感影像为信息源,辅之以1：5万地形图、1：5万土地利用现状图为参考,在对遥感影像进行解译的基础上,利用RS、GIS 技术及景观格局分析软件,获取相关景观格局指数的变化数据,分析近10 a研究区景观格局的动态变化特点。研究表明：随着时间的推移希拉穆仁草原旅游地的整体景观格局发生了较大的变化,虽然草地总面积没有明显减少,但景观越来越破碎,被旅游干扰强烈分割后的草原斑块岛屿化现象明显加强,生态环境变得更加脆弱。其景观类型间的变化趋势和程度不尽相同,旅游用地面积迅速增长且斑块数量大、分布密集,成为草原旅游地景观趋于破碎的直接诱因。
The article took the tourist area in Xilamuren grassland of Inner Mongolia as study area, with remote sensing images of 2000, 2004, 2007 and 2009 as information source using a 1:50 000 topographic map and 1:50 000 land use map as reference. Through remote sensing image interpretation combination of remote sensing images and ground surveys, the spatial database was established. Acquiring the changes of data related landscape pattern indices using RS, GIS and the landscape pattern analysis software, the dynamic change characteristics of landscape pattern in the last ten years were analyzed. The results show that, with time going, the whole landscape pattern of tourist area in the Xilamuren grassland has taken great changes. The number of patches, patch density, the index of fragmentation and corridor density index were increasing. The mean patch area, aggregation index, the ratio of the largest patch to the landscape area decreased. Although the grass area did not significantly reduce, landscape became more and more broken, the islanding phenomenon of grassland patch intensifies obviously under anthropogenic interference, and ecological environment became more vulnerable. From the changes of landscape constitute, its trend and level of variation among landscape type were different. Under the impact of drought climate, high coverage grassland area decreased in the study area, the middle and low coverage grassland area increased, and the water and wetland area reduced. The rapid growth of tourism land area and its great number of patches as well as intensive distribution directly result in grassland landscape fragmentation. Reasonable regulation of tourist disturbance is the most important task of protecting grassland ecological environment in the future. In this article the dynamic change of landscape pattern was analyzed using remote sensing, GIS and landscape ecology method joining the tourism interference factors, to provide some reference for the ecological environment protection of grassland tourist area.
采用综合考虑高温事件温度强度、持续时间和发生面积等因子的区域持续性极端高温事件（regional continual high temperature event, RCHTE）判别方法和指标体系,分析中国近50 a RCHTE的时空变化特征。研究表明,中国RCHTE发生强度和频次较多的地区主要位于中国西北（西北西部和内蒙古西部）和东南地区（黄淮南部、江淮、江汉、江南和华南南部等地）,而中国东北和西南地区为RCHTE少发区;中国RCHTE发生频次、强度和影响面积在20世纪90年代前略呈减少趋势,90年代后呈现显著增加趋势,各指标在90年代末至21世纪初发生-突变,RCHTE增加趋势更为显著。
Affected by global climate changes and human activities, regional continual high temperature event (RCHTE) shows new trends, such as increasing intensity, higher frequency and larger range. RCHTE is one of the most serious disasters in China which does great harm to production and living conditions of human beings. It is very necessary to carry out RCHTE study synthetically and identify its temporal and spatial characteristics in China. In this paper, 642 meteorological station data of China from 1961 to 2010 were used to calculate air temperature. Intensity, area and duration of temperature were adopted to identify RCHTE. Then single index and integrated index were established to show characteristics of RCHTE. Besides, typical RCHTE case was chosen to analyze and test the methodology of RCHTE identification. Test result showed that RCHTE identify method coupled with single and integrated index can identify RCHTE correctly and effectively. On the base of the method, temporal and spatial characteristics of RCHTE in China from 1961 to 2010 are analyzed and results show that: there are 291 times RCHTE occurred in the past 50 years, including extreme RCHTE 31 times, severe RCHTE 59 times, moderate RCHTE 113 times and weak RCHTE 88 times. Distribution of RCHTE in China show obvious spatial characteristic. Moreover, spatial distribution of the intensity and frequency of RCHTE shows a good consistency. Regions with higher intensity and frequency of RCHTE mainly lie in Northwest of China (including western Northwest China and western Inner Mongolia) and Southeast China (including southern Huanghuai, Jianghuai, Jianghan, Jiangnan and southern South China) while intensity and frequency of RCHTE in Northeast China and Southwest China are relatively lower. Temporal variations of RCHTE analyses show that RCHTE in China has obvious increasing trends over the past 50 years. The accumulation of intensity, frequency, duration and area indices of RCHTE are relatively higher in 1960s and 1970s, while the indices are lower in 1980s. Since the 1990s, the annual accumulations of each index increase significantly. Especially after 2000, RCHTE increases even more quickly. Trend and mutation test for each index of RCHTE by Mann-Kendall method show that intensity, frequency, area and duration indices of RCHTE all show slightly decreasing trends before the 1990s, but increase significantly after the 1990s with the global warming. Each index of RCHTE has mutation from the late 1990s to the early 21st century and the increase trend of RCHTE is more significant.
区域旅游经济差异的时空格局与区域响应差异是旅游业发展研究的核心内容之一。以1996~2010年西南五省区的国内旅游收入和旅游人次为数据基础,综合运用标准差、变异系数、首位度等指标,分析了西南地区国内旅游经济发展差异特征及其旅游发展的区域响应差异,揭示各省市区国内旅游业发展的不同的区域响应,研究发现：① 西南地区国内旅游经济总体发展比较快,各地区国内旅游经济发展不平衡,省市区际国内旅游经济发展的绝对差距呈现逐年上升的趋势,且上升速度较快,由1996年的39.47亿元上升至2010年的638.94亿元,区际的旅游经济发展的变异系数波动不大,并在波动中缓慢下降。② 西南五省市区同一阶段不同省市区具有不同的响应类型;同一省市区在不同发展阶段具有不同响应类型;旅游收入响应类型和旅游客流量响应类型也不相同。在此基础上,从旅游资源禀赋、区域经济社会发展水平、交通区位条件3个方面对差异的内在影响因子进行了阐释,提出未来西南地区国内旅游经济突破的关键是从旅游资源依赖型模式向产业依赖型模式转变。
Spatial and temporal pattern of disparity of the regional tourist economy and regional response is a core content of tourism research. This article analyzes the disparity′s feature and mechanism of tourism economic development in southwest China, by indicators of standard deviation, coefficient of variation and primacy ratio based on statistic data of domestic tourism income and tourist passengers. The result indicates that it has an overally fast but not balanced development rate of domestic tourism industry in southwest China. An absolute gap in the region is rising more and more faster. Coefficient of variation is in fluctuation and being a drop trend. The five region have different response types in the same development stage with various features for each region. Meanwhile the responses of tourism income and tourist passengers is not the same too. Tourism resoures, eco-social development level and transport location are three most important factors inducing the above results. Finally, the article puts forward that the key of domestic tourism economy is to transform the mode from tourism resources dependent to tourism industry mode.
云覆盖是热红外遥感应用和地表温度(Land Surface Temperature, LST)遥感定量反演的重要障碍。如何估算热红外遥感图像中云覆盖像元的地表温度,是热红外遥感的前沿研究难题。以地表热量平衡为基础,根据地表温度的空间分布连续性、植被对地表温度的影响,提出三种解决云覆盖像元地表温度估算方案：空间插值修正法、植被关系修正法和改进型地表热量平衡法,并探讨云覆盖区地表温度空间分布的洼地效应现象、洼地效应强度及计算方法。基于地表热量平衡方程的洼地效应强度因子和影像灰度值之间关系的数值模拟,是三种估算方案切实可行的关键。
Land surface temperature (LST) is a very important parameter controlling the energy and water balance between atmosphere and land surface. Since it is difficult to obtain such information from ground-based measurements, it appears to be very attractive by using satellite thermal infrared measurements to estimate LST since it can be used for estimating surface temperature at global or local scale. Moreover, the estimation of LST by using satellite remote sensing data is feasible. Cloud cover is a major obstacle to thermal infrared remote sensing applications and remote sensing quantitative retrieval of land surface temperature. Furthermore, cloud frequently exists in most time and covers roughly half the surface of the Earth even if the sky is clear. This is the case especially in some regions of high latitudes in the north hemisphere, e.g. the tropics are covered by cloud for about 60% of the time. Therefore, the influence of clouds on LST deserves more discussion and how to estimate LST of pixels covered by cloud on thermal remotely sensed imagery is one of the cutting-edge research problems. In this article, based on the theory of surface energy balance (SEB), three methods, which are spatial interpretation adjustment method, the adjustment method by correlations between LST and Vegetation Indices (VIs) and improved surface energy balance method, have been put forward for the estimation of LST when the sky is cloudy. Moreover, the lowland effect of LST spatial distribution under cloud cover and the method for the calculation of its intensity (denoted as SE) were also discussed. Generally speaking, when SE equals to 1, it means that SE reaches its maximum due to thick cloud cover .While SE equals to 0, it means that there is no lowland effect in clear sky. SE is strongly affected by the cloud and surface conditions. That is to say, SE is influenced greatly by cloud properties such as the time it appears and lasts, its shape, thickness and height and surface characteristics. In normal conditions, SE reaches the highest at the center of cloud cover, and the closer to the cloud cover margin, the less it is. Numerical simulation of the relationship between the intensity factors of the lowland effect and the image gray value, which is based on the SEB, is the key to the practice of the three methods of LST estimation under cloudy conditions.
通过对岩板垱剖面氧化物含量分析及年代测定,揭示其常量地球化学特征,探讨澧阳平原晚更新世晚期至全新世中期的化学风化过程和环境变化。结果表明,岩板垱剖面沉积物出现不同程度Na、Ca元素亏损及TFe和Mn元素富集,其化学风化作用程度明显高于黄土高原黄土,稍高于镇江下蜀黄土,处于中等的风化阶段。多个风化指标的垂向变化表明岩板垱剖面化学风化强度表现为风化较强、风化较弱、风化加强和风化较强4个阶段的变化。化学风化强度指示澧阳平原27~6.0 ka B.P.间,气候环境经历了相对暖湿–凉湿–气候回暖–温暖湿润的演变过程。
Based on detailed field survey, oxide contents analysis and optically stimulated luminescence (OSL) dating of the samples from the Yanbandang(YBD) profile in Liyang Plain, the geochemical characteristics of major elements, the weathering process and environmental change from late Pleistocene to mid-Holocene were discussed. The results showed that the content of oxide is mainly composed of SiO2, Al2O3 and TFe2O3 (Fe2O3+FeO) and their percentage are between 86% and 90.8%. Compared to the average upper continental crust composition, Na and Ca have been leached out strongly, while total Fe and Mn relatively enriched in the sediments of the YBD profile. The intensity of chemical weathering in the YBD sequence was significantly higher than that of loess and paleosol in Loess Plateau, slightly higher than Xiashu loess in Zhenjiang, almost equal to the Yucheng profile in Liyang Plain, but obviously lower than the red soil from Xuancheng profile in Anhui Province, which indicated a moderate chemical weathering intensity under warm and moist conditions. Changes of the Chemical Index of Alteration (CIA), the Eluvial Coefficient, the Coefficient of Weathering and Eluviations (BA), the Index of Compositional Variation (ICV) and the analysis of A-CN-K and A-CNK-FM ternary diagrams suggested palpable differences in weathering intensity of the strata. There are four stages of weathering process in the YBD profile: relatively stronger weathering, relatively weaker weathering, intensifying weathering, and relatively stronger weathering. The weathering intensity of the yellowish brown soil at the top and bottom of YBD profile were clearly higher than that of the black brown soil and the black soil. Since the chemical weathering intensity is sensitive to climate change, the geochemical parameters can be used to unravel the environmental change to some extent. The higher CIA value reveals that the climate is relatively warmer and wetter in the end of the MIS3a stage. It becomes cooler during the LGM, but gradually returns to be warm again in early-Holocene. The climate in the mid-Holocene was the warmest and most humid compared to the aforementioned periods.
运用数理统计方法获取秦皇岛洋戴河平原地下潜水和海水的水化学统计特征,据此优选出4项海水入侵评判指标,建立各评判指标的背景值及指标等级体系,并将模糊数学综合评价法和地理信息系统结合起来评价研究区潜水含水层的海水入侵程度。研究结果表明：氯离子Cl-、电导率EC、溶解总固体TDS和潜在盐度是指示本区潜水含水层海水入侵程度的最佳指标,其判别海水入侵发生的下限值分别为250 mg/L、1 250 μs/cm、700 mg/L和8.5 meq/L;洋戴河平原潜水含水层的海水入侵程度总体上为中等水平,洋、戴河间浦河一带的潜水含水层海水入侵程度最为强烈。
Analyzing the distribution map of seawater intrusion degree can increase the knowledge of seawater intrusion mechanism, which is not only the important reference for water supplies of production and daily life but also the core content of seawater intrusion survey and research. In this article, four effective indicators for seawater intrusion of Qinhuangdao Yangdai River Plain which is located in the northeast of Hebei Province were selected out according to the different hydrochemical characteristics of fresh groundwater, brackish groundwater and seawater using the method of mathematical statistics. And then, the background values and index system of those seawater intrusion indicators were built to carry on seawater intrusion degree evaluation work based on the approach of fuzzy synthetic evaluation and geographic information system. The research results can be showed as follows: The chloride ion (Cl-), electric conductivity (EC), total dissolved solids (TDS) and potential salinity are the optimal seawater intrusion indicators which can help to distinguish the intruded samples from all groundwater samples. The background value of study area for chloride ion concentration, EC, TDS and potential salinity are 83.06-243.8 mg/L,600-1 222 μs/cm,341.82-679.14 mg/L and 2.92-8.05 meq/L, respectively. The lower limit value of chloride ion concentration, EC, TDS and potential salinity are 250 mg/L, 1 250 μs/cm、700 mg/L and 8.5 meq/L, respectively, which can manifest the occurrence of seawater intrusion. The groundwater samples identified seawater intrusion degree as rank II and rank III , make up 74% of all samples , which reveals that seawater intrusion degree of study area generally belongs to the medium level. On the basis of the distribution map of seawater intrusion degree, the seawater intrusion degree of the alluvial aquifers around Pu River between the Yang River and Dai River is the highest.
The Neolithic Tenghualuo Site in Lianyungang, which belongs to Longshan period, is the first prehistory city of China with both inner and outer structure ever been discovered. According to the analysis on the heavy-metal accumulation and grain size of profile(L1) and agricultural production area profile(L2) in the city residential area, respectively, it was found that anthropogenic-related accumulation of heavy metals in soil already had occurred in Longshan period, but only appeared in the city residential area. Cu, Pb and Zn accumulated the most obvious, whose enrichment factor values are 1.91, 1.35 and 1.29 respectively. Compared with the discovery of bronze archaeology, it can be sure that Tenghualuo Site has been in Chalcolithic Age. Meanwhile, the research of soil grain size based on soil source components separation method revealed that the soil in residential area had relatively unique parent material because of city protection during 4 500-4 200 a B.P., large-scale or prolonged flooding events have occurred in agricultural production area during this period, by which the proportion of diluvium was 30%, and this may destroy agricultural production condition, and causes the heavy-metal accumulation decline, eventually lead to the entire civilization disappeared. The findings above show that although the city can protect original society, the changes of natural environment still have decisive influence on original agricultural production, which finally decided the vicissitude of prehistoric civilization.
利用COUPMODEL 模型,对唐古拉研究区活动层土壤的水热特征进行模拟,与观测结果进行对比发现,在活动层土壤温度方面,COUPMODEL模型的模拟结果R2>0.94,其平均值为0.98,均方根误差较小,模拟效果较理想;在活动层水分特征方面,模拟结果存在一定偏差,R2介于0.88~0.93之间,平均值0.90,均方根误差平均值4.24,基本反映了高海拔多年冻土区活动层水热变化;在土壤热通量方面,0~20 cm土壤热通量的模拟结果与观测值基本一致;模型模拟的冻结深度在3 m左右,接近观测值,COUPMODEL模型可用于多年冻土区活动层土壤水热变化规律研究。
To study the water-heat characteristics of soil in the active layer in high altitude permafrost regions and to examine the interaction between soil and moisture under freeze-thaw cycles, a physical process by the CoupModel was used to simulate the soil temperature and moisture in the active layer, using the meteorological, the soil thermal and the moisture data on different depths in the active layer at the Tanggula test site. Comparisons between simulated and monitored data in situ showed that: 1) for soil temperature in the active layer, the simulated results fit well with the monitored, and the determination coefficient (R2) is more than 0.94 with the mean value of 0.98 while mean square deviation is relatively small, implying the CoupModel could successfully simulate the soil temperatures. 2) For soil moisture, results generally reflect water content variation in the active layer with R2 ranging from 0.88 to 0.93, the mean is 0.90 and the mean square deviation is 4.24, indicating a bit poor accuracy compared to soil temperature. 3) As to the heat flux of soil within the depth of 0-20 cm, results simulated is consistent with the monitored. The simulation accuracy is improved with depths, which may be related to the depth from the natural ground surface. The frozen depth is about 3.0 m, which is close to the observed data. It is concluded that the CoupModel can be well applied to study soil water-heat characteristics of the active layer in permafrost regions with higher elevations in Qinghai-Tibet Plateau.
以黑河中游湿地为研究对象,分析木本、高草、低草3种湿地植被类型土壤有机碳的分布特征及影响因素,结果表明,土壤有机碳含量的大小依次为高草>低草>木本植被类型,0~20 cm的差异均达到显著水平（p<0.05）。低草植被类型有机碳的空间变异最大,木本植被居中,高草植被最小。高草、低草和木本植被0~40 cm土壤有机碳密度分别为7.33、5.44和4.25 kg/m2。高草、低草植被以表层土壤（0~10 cm）有机碳含量更高,分别占0~40 cm的32%,31%,木本植被以亚表层（10~20 cm）最高,占33%。土壤有机碳含量与土壤含水量、磷素呈显著正相关（p<0.05）,与土壤质量、pH值呈显著负相关（p<0.05）。
Wetland ecosystem plays an important role in global carbon budget. However, the soil organic carbon (SOC) storage of wetland has been studied poorly in arid region. The distribution of SOC and its influence factors at three types of wetland vegetation (high herb vegetation, lower herb vegetation and woody vegetation) were analyzed in the middle reaches of the Heihe River. The results showed that the SOC contents at 0-10 cm, 10-20 cm and 20-40 cm depths were in the order of high herb wetland vegetation > lower herb wetland vegetation > woody wetland vegetation. The differences in organic carbon content among the three types of wetland vegetation were significant at 0-10 cm and 10-20 cm depths of soil. The coefficient of variation of SOC was greatest in the lower herb wetland vegetation, and was least in the high herb wetland vegetation and secondary in the woody wetland vegetation. There was significant difference in SOC content between 0-10 cm and 20-40 cm depths of soil in the high herb wetland vegetation, difference was not significant in other two vegetation types. In accord with the distribution of SOC content, the soil carbon density in 0-40 cm depth was 7.33 kg/m2, 5.44 kg/m2 and 4.25 kg/m2 at high herb wetland vegetation, lower herb wetland vegetation and woody wetland vegetation, respectively. At high herb wetland vegetation and lower herb wetland vegetation, the SOC content decreased with soil depth and was more concentrated in the surface layer (0-10 cm) accounting for 32% and 31% of the total in 0-40 cm depth. While organic carbon content at the woody wetland vegetation was larger at the soil depth of 10-20 cm (accounting for 33% of the total in 0-40 cm depth). The SOC content was positively correlated with soil water content (p<0.01) and phosphorus (p<0.05), and negatively correlated with soil bulk density (p < 0.01) and pH (p<0.05). Moreover, SOC content in wetland vegetation had no obvious relationships with soil salinity and altitude. The difference in organic carbon among different soil types was not significant.
利用EOS-MODIS卫星的积雪反照率数据和一元线性回归法分析2001~2010年长江源区积雪反照率的分布及变化趋势。结果表明：① 长江源区积雪季积雪反照率空间分布差异大。冰川区是积雪反照率高值中心(0.67~0.91),长江源东部地区是低值中心(0.15~0.48)。② 积雪反照率空间分布四季变化明显,峰值出现在次年1月份。③ 长江源区近10 a积雪季平均积雪反照率在高海拔区和冰川区增大比较显著(0.001 2/a)。与积雪面积和积雪季降雪量变化呈显著正相关;而源区夏季各月积雪反照率有明显降低趋势,与夏季温度的变暖趋势呈正反馈关系。
Albedo determines surface absorption capability for the solar radiation and impacts the surface radiation balance. The albedo on snow and ice is higher comparing other surfaces, and the absorption of energy from the sun is little on an ice or snow field. Monitoring and researching snow and ice albedo characteristics and variation are necessary to provide accurate data and the theoretical basis for hydrological process research of snow and ice. EOS-MODIS satellite data of snow albedo (MOD10A1 on Level3)were used in the article to analyze the regional and seasonal distribution of snow albedo, as well as the inter-annual trends in the source region of the Changjiang River from 2001 to 2010 using softwares such as ArcGIS and ENVI. Based on the meteorological data of 3 stations on the source region of the Changjiang River from 2000 to 2010, the basic features of temporal changes of temperature and precipitation were investigated. The results show that: 1) Snow albedo were different with space distribution in the snow season in the source region of the Yangtze River. The snow albedo was high on the northern source region of the Yangtze River and on the southwest of the source region of the Changjiang River with 0.67 to 0.91, respectively, whereas part of the east of the source region of the Changjiang River was low (0.15 to 0.48). The distribution of snow albedo closely related to spatial distribution of snow depth and effected by altitude. 2) The seasonal spatial distributions of snow albedo changed obviously in the source region of the Changjiang River. The snow albedo for the large proportion area of study area were 0.66-1, 0.4-0.57, 0-0.4 and 0.48-0.66 in winter, spring, summer, and autumn respectively. The variation of the seasonal snow albedo between spring and summer was the largest with difference of 0.3 to 0.5. In monthly scales, the mean snow albedo of the whole source region of the Changjiang River had the largest value in January (0.6), and the lower values in July (0.41) and August (0.42). 3) For the first decade in 21th century, mean annual snow albedo during the snow season had non-significant increasing trend in the most areas of the source region of the Changjiang River, whereas it increased significantly on the high altitude regions. The rate of regional snow albedo in the source region of the Changjiang River is 0.0002/a, but it was up to 0.0012/a on the glacier areas of the study area. There were statistical significantly positive correlations between snow albedo and snow cover and precipitation (snow fall) during the snow season. This suggests that snow albedo was sensitive to snow fall through the snow season. 4)The monthly snow albedo in summer on the source region of the Changjiang River showed a decreasing trend from 2000 to 2010, which is markedly affected by summer temperature, and there was a positive feedback relationship between them.
基于MODIS 500 m分辨率数据,利用MODTRAN 4+模型和可见光波段、近红外波段的波段比方法反演雪粒径,建立1个消融期内的雪粒径变化的时间序列,通过采集七一冰川上设立的观测点对应时间段内雪粒径验证MODIS模拟的雪粒径值,结合位于观测点附近的气象站的气温数据,探讨气温对雪粒径的影响。结果表明,雪粒径的增长存在着明显的日变化趋势;模拟的雪粒径普遍高于实测的雪粒径值, 因此反演模型需要约为1.1倍的校正因子;气温对雪粒径的影响显著。
The 500 m resolution Moderate Resolution Imaging Spectroradiometer (MODIS) L1B scenes over Qiyi glacier, Qilian Mountain is used to estimate the snow grain size. The retrieval is based on ratios of near-infrared albedo to visible albedo which predicts snow reflectance as a function of snowpack grain size and ice absorption. “Bow-tie” effects were removed by the ENVI software. Atmospheric effects are taken into account and corrected through the MODTRAN4+ model. By this approach snow optical grain size was determined by the volume-to-surface area ratio on account of non-oriented spheroids produce the same scattering results as spheres. The time series analysis of derived grain size shows a good sensitivity to snow melting and snow precipitation events. This inversion technique has been validated using a combination of ground-based grain size measurements derived from the handle lenses which measure the snow grain size over the top 1 cm layer. The retrievals correlate well with measurements when radii is in range of -0.1-1 mm, although retrieved optical snow grain size general is lower than physical measured grain size ,the model may be need about a factor of 1.1. As part of validation analysis for the Qiyi glacier, the retrieved snow grain size from MODIS over selected sites in the period of September 7-15 in 2011 was compared to the temperature measurement of the automatic weather station near the selected sites. The relationship between the measured snow grain size, simulated snow grain size and average temperature patterns suggests that rapid destructive metamorphism of the fresh snow occurred when temperatures were near 0℃, once temperatures were higher than 0℃ and kept for a long time, the snow particle size change was evident, snow particle size increased significantly, and vice versa. But in this prossess, snow particle size also existed evolution process of deformation; snow particle size and temperature showed significantly positive correlation. The future work is to study the better cloud mask algorithm to remove the cloud effects and build the long and continuous time series of the snow grain size.