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1.
历史时期中国重大自然灾害时空分异特征(英文) 总被引：4，自引：0，他引：4
Based on historical documents and records this paper analyzes the characteristics of frequency and distribution of major disasters that took place in the history of China. The findings show that occurrences of different types of disasters varied and spatial pattern at provincial level are significantly different as well. The results also indicate that there is a strong relationship between type of disasters and spatial distribution and that the spatial pattern of losses was not the same as that of the frequency. The reasons are: (1) the hazard-formative environments which, to a large extent, determine the spatial pattern of the disasters are significantly different; (2) the losses caused by natural disasters were closely related to the concentration of economy and population. Number of deaths was usually large in areas where agriculture, culture and business were relatively developed. The spatial pattern of disaster losses is an evitable result of uneven economic development in the history of China. 相似文献
2.
黄淮海平原农区土地利用转型及其动力机制（英文） 总被引：7，自引：0，他引：7
Land use transition refers to changes in land use morphology, including dominant morphology and recessive morphology, of a particular region over a period of time driven by various factors. Recently, issues related to land use transition in China have attracted interest among a wide variety of researchers as well as government officials. This paper examines the patterns of land use transition and their dynamic mechanism in the Huang-Huai-Hai Plain during 2000–2010. First, the spatio-temporal patterns of land use transition, their characteristics and the laws governing them were analyzed. Second, based on the established conceptual framework for analyzing the dynamic mechanism of land use transition, a spatial econometric regression analysis method was used to analyze the dynamic mechanism of the five types of major land use transition in the Huang-Huai-Hai Plain at the county level. Land use pattern changes in the study area were characterized by an increase in construction land, water body and forested land, along with a decrease in farmland, unused land and grassland. The changes during 2000–2005 were much more significant than those during 2005–2010. In terms of factors affecting land use transitions, natural factors form the basis, and they have long-term effects. Socio-economic factors such as population and GDP, however, tend to determine the direction, structure, size and layout of land use transition over shorter time periods. Land law and policy factors play a mandatory guiding and restraining role in land use transitions, so as to improve the overall efficiency of land use. Land resource engineering is also an important tool to control land use transitions. In general, the five types of major land use transition were the result of the combined action of various physical, social and economic factors, of which traffic condition and location condition had the most significant effects, i.e. they were the common factors in all land use transitions. Understanding the spatio-temporal process of land use transitions and their dynamic mechanisms is an important foundation for utilizing land resources, protecting regional ecological environment and promoting sustainable regional socio-economic development. 相似文献
3.
基于改进场模型的中国中部地区城市影响范围研究 总被引：4，自引：0，他引：4
Due to unique advantages in clearly understanding the interrelationship between city and its hinterland, as well as city and city, the study of urban spheres of influence is becoming highlight in regional research. This paper improves traditional field model from two aspects: the composite indicator and regional accessibility, in order to delineate urban spheres of influence more reasonably. Taking three years of central China as a case study, this paper investigates dynamic evolution of urban spheres of influence. Focusing on the evolution of spatial pattern, we abstract five types and its corresponding three stages theoretically. Finally, recommendation of development has been made for each stage. This study undertakes certain exploration in the study of urban spheres of influence from the perspective of theory and practice, hoping to provide some references for the study in this field and other regional research. 相似文献
4.
《地理学报(英文版)》2017,(10)
Land cover is the most evident landscape signal to characterize the influence of human activities on terrestrial ecosystems.Since the industrial revolution,the expansion of construction land has profoundly changed the status of land use coverage and changes.This study is proposed to reconstruct the spatial pattern of construction land(urban construction land and rural settlement land)for five historical periods over the past 200 years in Jiangsu Province with 200 m′200 m grids on the basis of quantitative estimation.Urban construction land is estimated based on data about city walls,four gates along walls,and other socio-economic factors.Rural settlement land is calculated based on the rural population and per capita housing allowance.The spatial pattern of historical construction land is simulated based on the distribution of modern construction land in 1985 with a quantitative-boundarysuitability control method and thorough consideration over connectivity of different land use types.The study concludes that:(1)the amount of construction land in Jiangsu Province is estimated at 963.46 km~2 in 1820,1043.46 km~2 in 1911,1672.40 km~2 in 1936,1980.34 km~2 in1952 and 10,687.20 km~2 in 1985;and(2)the spatial distribution of construction land features the great proclivity to water bodies and main roads and the strong polarization of existent residence.The results are verified directly and indirectly by applying the trend verification of construction land changes and patterns,the correlation analysis between rural settlement land and local arable land,and quantitative accuracy test of the reconstructed construction land to actual historical survey maps covering four sample regions in 1936. 相似文献
5.
Attribution analysis for water yield service based on the geographical detector method: A case study of the Hengduan Mountain region 总被引：1，自引：0，他引：1
Ecosystem services, which include water yield services, have been incorporated into decision processes of regional land use planning and sustainable development. Spatial pattern characteristics and identification of factors that influence water yield are the basis for decision making. However, there are limited studies on the driving mechanisms that affect the spatial heterogeneity of ecosystem services. In this study, we used the Hengduan Mountain region in southwest China, with obvious spatial heterogeneity, as the research site. The water yield module in the In VEST software was used to simulate the spatial distribution of water yield. Also, quantitative attribution analysis was conducted for various geomorphological and climatic zones in the Hengduan Mountain region by using the geographical detector method. Influencing factors, such as climate, topography, soil, vegetation type, and land use type and pattern, were taken into consideration for this analysis. Four key findings were obtained. First, water yield spatial heterogeneity is influenced most by climate-related factors, where precipitation and evapotranspiration are the dominant factors. Second, the relative importance of each impact factor to the water yield heterogeneity differs significantly by geomorphological and climatic zones. In flat areas, the influence of evapotranspiration is higher than that of precipitation. As relief increases, the importance of precipitation increases and eventually, it becomes the most influential factor. Evapotranspiration is the most influential factor in a plateau climate zone, while in the mid-subtropical zone, precipitation is the main controlling factor. Third, land use type is also an important driving force in flat areas. Thus, more attention should be paid to urbanization and land use planning, which involves land use changes, to mitigate the impact on water yield spatial pattern. The fourth finding was that a risk detector showed that Primarosol and Anthropogenic soil areas, shrub areas, and areas with slope 5° and 25°–35° should be recognized as water yield important zones, while the corresponding elevation values are different among different geomorphological and climatic zones. Therefore, the spatial heterogeneity and influencing factors in different zones should be fully con-sidered while planning the maintenance and protection of water yield services in the Hengduan Mountain region. 相似文献
6.
The data used in this paper were acquired at 19 quantitative dredging stations and 4 trawling stations during the three crusies of the 4th Chinese Antarctic Research Expedition for investigating the shallow sea benthos in Great Wall Bay, in the period from December 1987 to March 1988. Based on environmental characteristics, diversity of species composition and the eveness of interspecific distribution of individuals, cluster methods were used to divide the investigated area into three benthic community distribution areas. The structures of the various communities were further divided into 3 structure types, namely, high diversity, intermediate diversity and low diversity types. From the study of the relationship between community structure and environmental factors it was pointed out that there was an extremely close relationship between benthic communities structure and the stability of the bottom types and sediments, whereas in sea areas where the depth gradient is not large, there is no obvious relat 相似文献
7.
A computer program(FEA)is presented for processing historical laboratory data.It performs on a list ofsample entries stored in a laboratory information management system.Using an algorithm which is basedon fuzzy set theory,FEA classifies the entries into a limited number of clusters called sample types.Theclassification is fully user-defined.The program transforms the historical data into a representation whichis more suitable for studying the performance of the laboratory or which can be used as preparation for asimulation project. 相似文献
8.
塔里木河流域绿洲城镇发展与水土资源效益分析(英文) 总被引：4，自引：1，他引：3
This paper examines the spatial pattern of land and water resources as well as urbanization and their interactions in the Tarim River Basin, Xinjiang, China. In order to do so, we extract the data associated with efficiency of land and water resources and urbanization for the years of 1995, 2000, 2005 and 2008. Specifically the paper investigates the extent to which agglomeration of population and economic activities varies geographically and interplays with spatial pattern of resources efficiency through computation of Global Moran’s I index, Getis-Ord Gi* index and a coordinated development model. The method used provides clear evidence that urbanization, land and water resources efficiency have shown uneven spatial pattern due to oasis distribution, climate, and initial phase of urban development. Some conclusions can be drawn as follows.(1) Agglomeration and dispersion of urbanization are not consistent with those of land and water resources efficiency.(2) Evolution of the hot and cold spots of urbanization, and land and water resources efficiency, in different trajectories, indicate that there are no significant interactions between them.(3) The evidence that numbers of hot and cold spots of the three factors present varying structures reveals the dominance of unequal urban development in the study area.(4) Significant differences are also found between sub-river basins in terms of the three factors, which is a reflection of the complex physical geography of the area.(5) The degree of coordinated development of cities in the Tarim River Basin is generally low in part as a reflection of difference in spatial patterns of the three factors. It is also shown that the pattern of the degree of coordinated development is relatively stable compared with evolution of hot and cold spots of the three factors. 相似文献
9.
As one of the most critical impact factors of global change, historical land-use change is an indispensable input in climate and environment simulations. To better understand the cropland change in the Guanzhong area, gazetteers, statistics, and survey data were collected as data sources. Methods of registered tax-paying cropland data collection, selection of time points, and data interpolation and calibration were used to reconstruct changes in the cropland area. The cropland area data at the county level were allocated to 1 km×1 km grid cells. The total cropland area in the Guanzhong area was influenced by changes in population, wars, natural disasters, and land-use types, and it fluctuated from 1650 to 2016. From 1780 to 1830, the cropland expanded in the northern and western parts of Guanzhong area, and the cropland in the north of Qinling Mountains increased slightly. The spatial pattern of cropland reached its maximum range in 1980, and the cropland area declined in the whole study area, especially in the cities of Xi'an and Xianyang in 2016. The comparison between HYDE 3.2 and the data obtained in this study showed that the grid cells of HYDE 3.2 exhibit lower values of cropland area fractions in the Guanzhong Basin and higher values in high-altitude areas around the Guanzhong Basin as compared to those in this study. 相似文献
10.
Food security is the primary prerequisite for achieving other Millennium Development Goals(MDGs).Given that the MDG of“halving the proportion of hungers by 2015”was not realized as scheduled,it will be more pressing and challenging to reach the goal of zero hunger by 2030.So there is high urgency to find the pattern and mechanism of global food security from the perspective of spatio-temporal evolution.In this paper,based on the analysis of database by using a multi-index evaluation method and radar map area model,the global food security level for 172 countries from 2000 to 2014 were assessed;and then spatial autocorrelation analysis was conducted to depict the spatial patterns and changing characteristics of global food security;then,multi-nonlinear regression methods were employed to identify the factors affecting the food security patterns.The results show:1)The global food security pattern can be summarized as“high-high aggregation,low-low aggregation”.The most secure countries are mainly distributed in Western Europe,North America,Oceania and parts of East Asia.The least secure countries are mainly distributed in sub-Saharan Africa,South Asia and West Asia,and parts of Southeast Asia.2)Europe and sub-Saharan Africa are hot and cold spots of the global food security pattern respectively,while in non-aggregation areas,Haiti,North Korea,Tajikistan and Afghanistan have long-historical food insecurity problems.3)The pattern of global food security is generally stable,but the internal fluctuations in the extremely insecure groups were significant.The countries with the highest food insecurity are also the countries with the most fluctuated levels of food security.4)The annual average temperature,per capita GDP,proportion of people accessible to clean water,political stability and non-violence levels are the main factors influencing the global food security pattern.Research shows that the status of global food security has improved since the year 2000,yet there are still many challenges such as unstable global food security and acute regional food security issues.It will be difficult to understand these differences from a single factor,especially the annual average temperature and annual precipitation.The abnormal performance of the above factors indicates that appropriate natural conditions alone do not absolutely guarantee food security,while the levels of agricultural development,the purchasing power of residents,regional accessibility,as well as political and economic stability have more direct influence. 相似文献
11.
以安徽垦殖为例,充分考虑各种误差因素,把误差控制在一定范围的要求,借助历史学的研究方法对文献资料进行考证与鉴别,运用现代的统计科学对数据进行一致性检验与修正,尝试对太平天国战争前后安徽的垦殖变动进行量化处理,提出耕地数据重建及无资料时段垦殖率插补的可行性方法,并以此完成战争前后分县垦殖率的重建,进而利用GIS再现区域垦殖变化格局。资料检验表明,这是一种较为合理的土地利用空间格局度量方法。 相似文献
12.
《自然地理学》2013,34(1):64-78
Research efforts studying dune fields as spatial units are limited and the historical dynamics associated with dune field-scale pattern attributes are currently not well documented. Historical repeat aerial photography was used to quantify temporal changes in the crescentic dune pattern at the White Sands Dune Field, New Mexico. A Geographic Information System (GIS) was used to digitize ~ 14,000 dune crests from the combined photoset. Crest length, sinuosity, spacing, orientation, transport vector, and defect density were calculated from these measurements and statistically analyzed. The pattern analysis revealed that crest length, sinuosity, and defect density were highly variable pattern elements over a 60-year period. These dune pattern elements also exhibited temporal relationships, such as the inverse relationship between crest length and sinuosity over time. Defect density calculations revealed that the dune field is trending to a possible state of disorganization. This trend was temporarily interrupted in 1985 by a massive period of organization in which crest length was inversely related to defect density and defect density was proportionally related to sinuosity. The temporal variations in these pattern elements and the episodic organizational event in 1985 were likely climatically induced. 相似文献
13.
The shapes of 268 tropical cyclone tracks in the South West Indian Ocean (SWIO) basin are investigated over the period 1977 to 2011 using an established metric for track sinuosity. Original cyclone position data from the RSMC La Réunion area of responsibility were accessed from the IBTrACS archive maintained by NOAA. Cyclone track sinuosity was measured within a GIS environment and the filtered results were normalised with a cube-root transformation function to reduce positive skew in the output sinuosity distribution. Several key findings from spatial and temporal analysis of sinuosity results may be highlighted. To assess geographical patterns, mapping tracks within designated quartile categories (straight, quasi-straight, curving and sinuous tracks) indicates which land areas in the SWIO are more likely to be affected by cyclones following sinuous tracks that are more difficult to forecast, in particular Madagascar and the islands of Réunion and Mauritius. Over the past three decades, the temporal sinuosity pattern shows a high degree of variability that will probably continue into the future. Yet crucially, a number of conspicuous episodes of relatively magnified or subdued sinuosity are recognised compared to long-term averages. This may present opportunities for identifying major climatic controls on regional anomalous cyclone migration behaviour. Within the average yearly cyclone season, the early months (September–December) have a tendency to produce more predictable straighter-moving cyclones, whereas January stands out as the singular month marking an abrupt swing towards a greater proportion (64%) of curving and sinuously-moving storms. This finding is of importance for vulnerability assessment, because a strong positive correlation is also identified between track sinuosity and cyclone longevity, such that storms steering less predictable sinuous courses are also those that tend to survive for longer durations. 相似文献
14.
Soile Tissari Vesa Nykänen Jouni Lerssi Mikko Kolehmainen 《Natural Resources Research》2007,16(2):159-169
Weights-of-Evidence (WofE) and Radial Basis Function Link Net (RBFLN) were applied to soil group mapping in eastern Finland.
The data consisted of low altitude airborne geophysical measurements, Landsat 5 TM-satellite image, and digital elevation
model (DEM) and slope information derived from it. Probability maps were constructed for each soil group one by one and combined
into a prediction map of soil groups using maximum posterior probability (WofE) or pattern membership (RBFLN). Self-Organizing
Map (SOM) and Sammon’s Mapping were applied for selecting the data sets for modeling and visualizing the data. The soil types
belonging to each soil group used in the Arc-SDM modeling were defined by clusters revealed by the SOM and Sammon’s Mapping
algorithms. The soil types with similar characters were collected in the same cluster. Numerical evaluation of the models’
performance was performed using the confusion matrix. The Ratio of Correct Classifications (RCC) for the best WofE model was
0.64 in the training area and 0.61 in the testing area. The RCC for the best RBFLN model was 0.62. Modeling of soil groups
using Arc-SDM is time consuming because models need to be constructed for each soil group before combining them into a final
prediction map. In this study a simple method was tested for combining the maps. In the future, more attention should be paid
to combining the posterior probability models and also to selecting data sets used for modeling. 相似文献
15.
从清代后期西北地区的历史文献中整理出1876~1878年气候信息和农业信息,即少雨或干旱等事件、蝗虫事件、歉收和饥荒事件。资料来源包括清代中央和新疆地方的档案,新疆、甘肃和宁夏的地方志,重要人物的文集等。结果显示1876~1878年西北地区中西部出现干旱及相关事件。将以上事件绘制成图,发现这些事件分布在甘肃、宁夏和新疆东部,最西可达新疆天山北麓中部。整体上,事件以1877年为范围最广、最为严重。在此次干旱事件中,西北地区中西部的经济社会受到的影响有限,只在部分县域出现粮食歉收和饥荒,未发生同期华北地区普遍存在的“奇荒”。 相似文献
16.
Fluvial processes of the downstream reaches of the reservoirs in the Lower Yellow River 总被引：1，自引：0，他引：1
Evolution of the river channel downstream of reservoirs is a complex process that is closely related to the operational mode of the reservoirs and the channel boundary conditions. Numerous studies have been carried out on the fluvial processes of downstream reservoirs. However, only a few of them have focused on the relationship between runoff-sediment conditions and channel pattern indicators. Also, the impacts of river training works on fluvial processes are seldom dealt with. In this paper, the evolutionary processes of three sections in the Lower Yellow River, including Tiexie-Yiluo River mouth reach, Huayuankou-Heigangkou reach and Jiahetan-Gaocun reach, were analyzed for variations in the channel boundary line and the mainstream between 1960 and 2015. Channel pattern indicators such as sinuosity, mainstream wandering range and width/depth ratio were analyzed based on field measurements obtained by the Hydrological Department of the Yellow River Conservancy Commission. The effects of river training works on the channel evolution are then described. Since 1960, numerous medium- and large-sized reservoirs have been built on the Yellow River, including Longyangxia Reservoir, Liujiaxia Reservoir and Xiaolangdi Reservoir. These reservoirs impound the runoff from upstream and retain the sediment, which changes the runoff and sediment conditions in the downstream reach. As a consequence, annual runoff and the frequency and peak of flooding have all decreased. As a result, the flow dynamics and their action on the river channel are also reduced, which changes the dynamic state of the river course. The discrimination results obtained using the single parameter discrimination rule and the discrimination equation show that the degree of wandering is weakened in the reaches studied. The variations in the channel pattern indicators show that the sinuosity increases and the wandering range decreases with a reduction in the total annual volume of water. However, the degree of wandering has little relationship to the sediment concentration. In addition, river training works play an important role in controlling the river course. Due to improvements in the river training works, the river course has become more stable under the same runoff and sediment conditions. A new discrimination rule that takes into account the impacts of the river training works is proposed. The discrimination results were found to fit well with the actual river pattern, which shows that the discrimination rule is applicable to the Lower Yellow River. The results show that the runoff and sediment conditions are the most important factors in the evolution of the river course. The river training works have at the same time limited the wandering range of the mainstream and played an important role in the fluvial processes. Both factors combined lead to the stabilization of the river. 相似文献
17.
1711-1982年云南雨季早晚序列的重建与夏季风变迁 总被引：1，自引：1，他引：0
According to the textual research into the historical documents dominated by archives yearly, as well as the verification with several other kinds of data, the later or earlier starting time of the rainy seasons in Yunnan during 1711-1982 has been reconstructed. The analysis indicates that there are obvious fluctuations in the starting date of the rainy seasons in Yunnan in a year or years, and long fluctuation on the decadal scale. The rainy season comes earlier in the early 18th century, later in the 19th century and earlier again in the 20th century. This reflects to a certain degree the gradual change of the summer monsoon in Yunnan. There exists an obvious quasi-3 years cycle, which is related to EI-Nino＇s quasi-3 years cycle, and a 11.3-year cycle which is notably related to the 11-year cycle of the solar activity of starting date of the rainy seasons in Yunnan. Meanwhile, the dissertation finds that the EI-Nino is very important to the starting date of the rainy seasons in Yunnan. The starting date of the rainy seasons in Yunnan often comes later or normally in the year of EI-Nino. However, there is an obvious imperfect period in such influence, which in turn may mean that there is a certain fluctuation in the effect of ENSO on Asian summer monsoon. 相似文献
18.
Historical first‐generation frontier roads in America's trans‐Appalachian West often evolved from buffalo and Indian trails into pioneer routeways such as Daniel Boone's Trace and, eventually, into twentieth‐century hard‐surface highways. Period cartographers found these routes difficult to document accurately, and present‐day scholars often depict them only on small‐scale maps, which simply illustrate connections between origin and destination points. Accurately mapping Kentucky's first‐generation roads at large scale requires detailed site and contextual topographic information over long distances, but historical maps, diaries, surveyors' reports, and other period documents often lack sufficient detail for route‐related sites to support mapping. Use of gis software enables positioning historical routes onto U.S. Geological Survey contour‐ and hill‐shaded base maps by mapping verifiable locations and linking them through interpretation of best‐choice routes that consider frontier migrants' transportation priorities, such as direction, distance, gradient, and land‐surface character. 相似文献
19.
黄土高原作物产量及水土流失地形分异模拟 总被引：2，自引：1，他引：1
De-farming slope farmland has been an effective measure in recent years for the improvement of the eco-environment and the mitigation of soil and water loss on the Loess Plateau. This paper, taking the Yangou Basin as a case study and using day-by-day mete- orological data of Yan'an station in 2005, simulated and analyzed the quantitative relation between crop yield, soil and water loss and topographic condition with the aid of WIN-YIELD software. Results show that: 1) topographic gradient has important influence on crop yield. The bigger gradient is, the lower the crop yield. Yields of sorghum and corn decrease by 15.44% and 14.32% respectively at 25° in comparison to the case of 0°. In addition, yields of soya, bean and potato decrease slightly by 5.26%, 4.67% and 3.84%, respectively. The in- fluences of topographic height and slope aspect on crop yield are slight. 2) Under the same topographic condition, different crops' runoff and soil loss show obvious disparity. Topographic gradient has important influence on soil and water loss. In general, the changing trend is that the soil and water loss aggregates with the increase of gradient, and the maximal amount occurs around 20°. The influence of topographic height is slight. Topographic aspect has a certain effect, and the fundamental characteristic is that values are higher at the aspect of south than north. 3) Topographic gradients of 5° and 15° are two important thresholds. The characteristic about soil and water loss with the variation of topographic gradients show that: the slope farmland with gradient less than 5° could remain unchanged, and the slope farm- land more than 15° should be de-farmed as early as possible. 相似文献
20.
《地理学报(英文版)》2016,(9)
Evolution of the river channel downstream of reservoirs is a complex process that is closely related to the operational mode of the reservoirs and the channel boundary conditions. Numerous studies have been carried out on the fluvial processes of downstream reservoirs. However, only a few of them have focused on the relationship between runoff-sediment conditions and channel pattern indicators. Also, the impacts of river training works on fluvial processes are seldom dealt with. In this paper, the evolutionary processes of three sections in the Lower Yellow River, including Tiexie-Yiluo River mouth reach, Huayuankou-Heigangkou reach and Jiahetan-Gaocun reach, were analyzed for variations in the channel boundary line and the mainstream between 1960 and 2015. Channel pattern indicators such as sinuosity, mainstream wandering range and width/depth ratio were analyzed based on field measurements obtained by the Hydrological Department of the Yellow River Conservancy Commission. The effects of river training works on the channel evolution are then described. Since 1960, numerous medium- and large-sized reservoirs have been built on the Yellow River, including Longyangxia Reservoir, Liujiaxia Reservoir and Xiaolangdi Reservoir. These reservoirs impound the runoff from upstream and retain the sediment, which changes the runoff and sediment conditions in the downstream reach. As a consequence, annual runoff and the frequency and peak of flooding have all decreased. As a result, the flow dynamics and their action on the river channel are also reduced, which changes the dynamic state of the river course. The discrimination results obtained using the single parameter discrimination rule and the discrimination equation show that the degree of wandering is weakened in the reaches studied. The variations in the channel pattern indicators show that the sinuosity increases and the wandering range decreases with a reduction in the total annual volume of water. However, the degree of wandering has little relationship to the sediment concentration. In addition, river training works play an important role in controlling the river course. Due to improvements in the river training works, the river course has become more stable under the same runoff and sediment conditions. A new discrimination rule that takes into account the impacts of the river training works is proposed. The discrimination results were found to fit well with the actual river pattern, which shows that the discrimination rule is applicable to the Lower Yellow River. The results show that the runoff and sediment conditions are the most important factors in the evolution of the river course. The river training works have at the same time limited the wandering range of the mainstream and played an important role in the fluvial processes. Both factors combined lead to the stabilization of the river. 相似文献