出境旅游是国际服务贸易的重要组成部分,是世界经济全球化的响应。出境旅游与国际服务贸易关系分析是制定出境旅游政策的基础之一。根据1985~2011年中国出境旅游和国际服务贸易时间序列的相关数据,采用计量经济学分析方法,系统探讨了出境旅游与国际服务贸易的关系。得出结论：① 出境旅游与国际服务贸易之间存在正相关关系;② 出境旅游与国际服务贸易存在长期稳定的动态均衡关系;③ 出境旅游与国际服务贸易存在短期波动回归长期均衡关系;④ 出境旅游是国际服务贸易出口的Granger原因,但不是国际服务贸易进口的Granger原因,国际服务贸易进出口均是出境旅游的Granger原因。
Along with the rapid development of global tourism, international tourism becomes an important part of international service trade, which is regarded as a significant parameter of internationalization level of a country or a region. In the context of rapid development in national economy, outbound tourism grows rapidly, which proves that international outbound tourism is the inevitable result of continuous global economic growth and international tourism’s rapid globalization. By the propulsion the development of global economy and international trade liberalization, international service trade has become one of the most important ways for the international economic intercourse activities and also has become the developing assistor of the global economy. However, at present, the relationship between the international outbound tourism development and international service trade is still controversial. According to the relevant data of international outbound tourism and international service trade in 1985-2011 in China, the relationship between international outbound tourism and international services trade is analyzed systematically in this ariticle. The results show that: 1) There is a positive correlation between the development of the Chinese international outbound tourism and international service trade. 2) A long-term stable dynamic equilibrium relationship is existed between the development of Chinese international outbound tourism and international service trade. The development of international outbound tourism and the growth of international service trade affect each other, and it has been worked out that the benefits of international service trade to the international outbound tourism are greater than that of international outbound tourism to the international service trade. 3) Short-term fluctuations are existed in the development of Chinese international outbound tourism and international service trade. Whereas, in a given time, these fluctuations could cause retrogression to the long-term equilibrium. Under the influence of the short-term fluctuation in the international tourism, international service trade would suffer a short-term fluctuation. However, international service trade import recovers faster than that of international service trade export to the long-term equilibrium. On the other hand, under the short-term effects of international service trade, international tourism would also have a short-term fluctuation, but international outbound recovers faster than international inbound tourism. 4) The international outbound tourism is in the granger causality with the international services trade exports, while the international outbound tourism is not the granger causality with international services trade imports. The international service trade imports and exports are the granger cause of international outbound tourism. The development of the outbound tourism is conducive to the export of international service trade, but the development of the outbound tourism does not play a significant role in the import of international service trade. The import and export of international service trades are beneficial to the development of outbound tourism. For this reason, China can stimulate the development of international service trade by developing international outbound tourism and hence by loosening the outbound tourism policy in the future.
旅游交通是旅游业碳排放的最重要环节。选择具有不同游客吸引半径的福州国家森林公园、太姥山山岳景区、武夷山风景名胜区为研究对象,通过对游客交通的问卷调查,探讨不同景区国内旅游交通碳排放的基本规律。研究表明,随着游客吸引半径增加,人均碳排放量显著增加,表现为福州森林公园<太姥山<武夷山。虽然每人每公里碳排放量亦表现为福州森林公园<太姥山<武夷山,但人均旅行距离的增大则是人均碳排放量增加的最主要因素。在350 km以内,每人每公里碳排放量和人均碳排放量随距离增加变化不明显或略微下降;而350 km以上,两者均随距离增加而急剧增长,这与距离对交通方式选择的影响有关。从旅游交通碳排放特征看,350 km大致可作为中途和长途旅行划分的界线。3个景区的年碳排放总量大小顺序为：武夷山>太姥山>福州森林公园,平均碳排放密度则表现为武夷山>福州森林公园>太姥山。各景区长途旅游者和乘坐飞机旅游者均占景区旅游交通碳排放的大部分,且其比例随景区游客吸引半径的增加而增多。因而减少长途旅行和乘坐飞机次数是降低景区旅游交通碳排放量的重要途径。
Tourism industry plays an unnegligible role in the global anthropogenic carbon dioxide (CO2) emission and climate change, with its contribution continuously increase in the future. Tourist transport is the most important activity resulting in CO2 emission in the tourism sector. To develop a low-carbon tourism industry, it is therefore necessary to assess both the patterns and causes of CO2 emission associated with tourist travel. This study selects three tourist destinations in Fujian with an increasing average tourist travel distance, namely Fuzhou National Forest Park (FZ),Taimushan National Key Scenic Spots (TMS), and Wuyishan Scenic Area (WYS), to determine the total amount, intensity, and spatial patterns of CO2 emission from domestic tourist transport. In each tourist destination, a questionnaire survey on tourist travel mode and travel distance was conducted during August to October 2010. Mean CO2 emission from individual tourist of these destinations increased with average travel distance, ranked as FZ (15.9 kg CO2/person) < TMS (105.3 kg CO2/person)<WYS (232.9 kg CO2/person). Though CO2 emission per person-kilometer also increases (FZ, 0.097 kg CO2 /(person·km); TMS, 0.134 kg CO2 /(person·km); WYS, 0.159 kg CO2 /(person·km)), the increase in average travel distance is mainly responsible for the increment of CO2 emission from individual tourist. For each destination, CO2 emission per person·km or per individual tourist within 0-350 km changed little or even declined slightly with increase in travel distance, but increased dramatically beyond 350 km, reflecting the impacts of travel distance on choice of transport mode. Thus, the distance of 350 km can be identified as a threshold for defining the medium- and the long-distance trip based on the transition in CO2 emission with travel distance. The annual total CO2 emission for these destinations rankes as WY (692 899 t)>TMS (65 651 t)>FZ (31 859 t), and the mean CO2 emission density decreases in the sequence of WYS (946.3 t/km), FZ (389.0 t/km) and TMS (166.6 t/km). Depended on both the tourist number and CO2 emission per tourist, CO2 emission density changes with travel distance and differs among destinations, which peaks at 700 km and 1 750 km in WYS, at 250 km and 2250 km in TMS, and at 75 km, 250 km, and 900 km in FZ. The major contribution to total CO2 emission in tourist transport comes from the long-distance and the aerial tourists, which increases with increasing average travel distance. Though tourists with travel distance longer than 350 km occupy only 5.5%, 27.8% and 81.3% of total tourist number respectively in FZ, TMS and WYS, they accounted for 65.1%, 90.0% and 98.7% of total CO2 emission accordingly. The aerial tourists are responsible for 51.3%, 75.4% and 87.8% of total CO2 emission, though they only contribute to 1.5%, 6.29% and 31.1% of total tourist number. Thus, to avoid long-distance or aerial trips is the most important way to cut down the CO2 emission bill associated with travel transport. Efforts that select short-distance trips or trips on more energy-efficient transport should be encouraged.
利用逐日地面降雪观测资料,分析中国25ºN以北范围内降雪量、降雪日数、雪带分布和各强度降雪的气候学特征,得到以下结论：① 雪季长度与年降雪日数在东部呈纬向分布,大兴安岭北部最长（>210 d）,长江以南最短（常年无雪或偶尔降雪）;在西部青海省南部和西藏自治区北部最长（>300 d）,滇、川、藏交界处及新疆自治区北部较长,南疆较短（<60 d）。年降雪量东南部最少,东北和西北北部较多（>30 mm）,青海和西藏降雪量最多（>60 mm）。平均降雪强度江淮一带最大。② 根据雪季降雪频次划分中国的雪带,东北大部、内蒙自治区东部、新疆北部、青藏高原大部、秦岭等地区为常年多雪带;长江以南的滇南、四川盆地、江浙沿海等地区为永久无雪带;其余地区为常年降雪带和偶尔降雪带。③ 不同区域各级降雪日数占总降雪日数的比例都是暴雪日数最少,大雪日数其次,小雪日数最多;但中雪降雪量占总降雪量的比例在东北北部、华北、西北、新疆、东南、青藏高原东部等区域仅高于小雪降雪量,而在黄-淮地区仅次于暴雪降雪量。④ 降雪年内分配在东北北部、西北、新疆、青藏高原东部等地区都呈双峰型,最多雪时节在早冬和晚冬、早春,隆冬时节并不是降雪最多时间,黄-淮和东南地区呈单峰型,东南地区峰值更陡。⑤ 总降雪日数和除暴雪外的各等级降雪日数与地理位置关系较明显,在中国东部主要随着纬度升高增加,在中国西部随海拔高度增加而增加;随着纬度升高,东部和西部的总降雪强度都减小,西部的小雪强度也减小。
：Climatic characteristics of snowfall, snow days, snow belt north of 25°N in China is analyzed using the daily snow observation data. The following results have been obtained in the analysis.1) Snow season length and snow days have the feature of latitudinal distribution in the east, with the Da Hinggan Mountains recording the longest (>210 d) snow season, and no snow or only occasional snow all year round in the south of the Yangtze River. In the west, Qinghai Province has the longest (>300 d) snow season, followed by the junction areas of Yunnan, Sichuan and the Tibet. Snow season length in northern Xinjiang is close to the north of Northeast China. The least snowfall occurs in the southeast, and Northeast and northern Northwest record the higher snowfall more (>30 mm),and Qinghai and Tibet are characterized by the highest snowfall(>60 mm). Maximum snowfall intensity is in the Yangtze-Huaihe region. 2) Snow belts are divided based on snowfall frequency: the Northeast and eastern Inner Mongolia, Northern Xinjiang, the Qinghai-Tibet Plateau, and the Qinling Mountains are snow-frequent belts. Southern Yunnan, Sichuan Basin, coastal areas of Jiangsu and Zhejiang and other areas are permanent snow-free belts.The other areas are snow-ordinary belts and snow-occasional belts. 3) The percentage of snowstorm days to total snow days is generally low in all of the regions. The highest percentage is seen for light snow days to total snow days. In view of the ratio of snowfall of all categories to total snowfall, the proportion of snowstorm witnesses the lowest value, followed by heavy snow, and light snow has the highest value in the north of Northeast, North, Northwest, Xinjiang and eastern Tibet Plateau. However, Southeast China is characterized by lowest value of the ratios for light snow, and the highest value for snowstorm. 4) The double-peak distribution of snowfall within the year is seen in northern Northeast, Northwest, Xinjiang and eastern Tibet Plateau, and the Yellow-Huai River basins and Southeast have a single-peak distribution of snowfall. 5) The total snow days, heavy snow days, medium snow days and light snow days generally increase with increasing latitude in the East of China, meanwhile with increasing altitude in the West; with increasing latitude, the total snowfall intensity has a decreasing trend in both the East and the West, also the small snow intensity in the West.
As is well-known, ever since the 1980s, Human Geography in China has achieved comprehensive rehabilitation and it maintains an extraordinary growth speed. Bibliometrics methods is used in this paper to collect statistics of literature which have been published on the three Chinese authoritative geographical journals “Acta Geographica Sinica”, “Scientia Geographica Sinica " and “Geographical Research” from 1980 to 2010. With the object of the articles in Human geography, features of the articles and authors which include the space-time characteristics, research field, methods, and institutes are all analyzed comprehensively. This paper combines the development process and the research hotspot of Human Geography in China and prospects the trend of human geography development in the later period. Results show that Chinese Human Geography emphasizes on the practical applicability and has intensive exchanges as well as intersects with other subjects. What’s more, a mature system of Human Geography authors of the three journals is taking shape. However, there are several shortcomings during the fast improvement, such as the disequilibrium in the development of sub-subjects and distribution of researchers, and lack of guidance theories and innovative methods and models. Only by solving these problems can China’s Human Geography keep a rapid and sound development.
基于日常公路客流的城市间关系与结构研究是一种重要的省域空间结构研究方法。作为城市间人流交往的重要组成部分,日常公路客流从动态关系视角反映了城市间的功能结构,更为清晰地展现省域空间的内在关系特征。通过对公路客流替代数据的进一步精确化,全面分析了安徽省域城市间每日公路客流的强度特征与结构特征,主要结论为：① 省域整体呈现单中心的结构特征,受省域中心城市合肥直接影响并紧密联系的城市有巢湖、六安和淮南,三者是构筑合肥都市圈的主体;② 以芜湖、马鞍山、安庆、铜陵为主体的皖江城市带城市间联系紧密,是安徽省域经济发展和城镇化的重要载体,其影响和联系范围包括池州和宣城,其中芜湖、安庆是皖江城市带的枢纽城市;③ 皖北地区城市间关系较为薄弱、分散,阜阳-亳州、淮北-宿州以及蚌埠-淮南三对城市间联系较为紧密,是皖北3个重要的城市发展组团,其中淮南是皖北区域链接合肥都市圈的枢纽城市。
The analysis on intercity relationship and regional spatial structure from the perspective of passenger flow of long-distance coach travel is an important approach to provincial spatial structure studies. Daily passenger flow of long-distance coach travel is a significant part of passenger flow among cities which can reflect functional intercity relationships and reveal the inner-provincial spatial relationship clearly. Based on the daily passenger flow of long-distance coach travel, in this article, Anhui Province is taken as an example. The characteristics of intercity relationships and spatial structure of Anhui Province is explored. To examine the characteristics of intercity relationships and spatial structure of Anhui Province, the research data are analyzed from two aspects. 1) The intensify characteristics of the intercity passenger flow. Passenger flow is graded according to the numerical size, then the passenger characteristics of traffic flow in different regions are analyzed in this article, especially focusing on relationships between the provincial capital (Hefei) and other cities in this province. 2) The structural characteristics of intercity passenger flow. According to directions of the largest passenger flow and the second largest passenger flow, the overall trend and spatial structure of the daily population movements among cities are analyzed, and the provincial nodes in the urban network from the perspective of topological characteristics and the flow strength on the city level are examined in this article. The conclusions are as follows: 1) On the whole, Anhui Province presents a mono-center structure, and the inter-regional links between cities are relatively weak except the center city (Hefei); Hefei affects and maintains frequent contact with Chaohu directly, Lu'an and Huainan. There seems to be a high possibility that these three cities would become a major part of the metropolitan area of Hefei, the economic center and capital of Anhui Province. 2) Wuhu, Ma'anshan, Anqing and Tongling connect with each other tightly, and are the main constitutions of urban belt in Wanjiang, an important carrier of economic development and urbanization in Anhui Province, and further influence Chizhou and Xuancheng. 3）Intercity relations are weak and scattered in the northern region of Anhui Province. The three pairs of cities—Fuyang and Bozhou, Huaibei and Suzhou, Bengbu and Huainan, are important urban groups in the northern Anhui Province. Each of them maintains a close contact within the urban group. And Huainan is the regional hub of northern Anhui Province.
With the prosperity and development of the automotive service industry, as well as the acceleration of urbanization in China, the automotive service industry has become an important part of urban modern service industry, which on turn has an increasing impact in urban space. Taking Nanjing as a case, this paper analyzes and compares the overall spatial agglomeration as well as spatial agglomeration based on sub-industry of automotive service industry. The result indicates that different automotive service industry show different characteristics of spatial agglomeration. Then the overall spatial agglomeration characteristics of automotive service industry were concluded as follows: 1) It shows the characteristics of layer distribution. The five sub-industry, namely car sales industry, auto repair and maintenance industry, auto parts industry, car rental industry and automobile club, agglomerates differently in different layer. 2) In sum, the automotive service industry indicates the feature of small gathering and large dispersion. The overall spatial layout of automotive services industry is relatively fragmented except to several larger gathering areas. 3) Most of the automotive service industries are distributed around the city trunk roads. Thus, it can be concluded that the spatial layout of automotive services is closely related with trunk roads.
In the process of rapid urbanization, the rural labor force pouring into the cities leads to the rising of many social and economic problems in the country. In this study, three typical villages in the central area of Shanxi Province are chosen for empirical research from the perspective of rapid urbanization, especially from the theoretical perspective of the influence of urbanization on rural areas. It is found that the outflow of rural labor force phenomenon is quite prominent. The proportion that peasant households which have migrant workers is over 60%, and there is also a trend that elder migrant worker who has no special skills returns home. In addition, it is also found that there are some other issues in rural areas, such as aging, the low education of children, the woman managing the family alone, the dismantling of traditional rural society, and so on. These problems are inevitable in the process of rapid urbanization.
Information Geography studies the geography of human information dissemination, including spatial distribution rules of information dissemination, spatial structure and its spatial effects, especially the impacts of spatial organization of human societies and economics, as well as the geographical phenomenon induced by virtual reality technologies. Nanjing University embarks on the development of Information Geography systematically with a long history, while deeply rooted in traditional advantageous discipline of geography. Information Geography in Nanjing University produces a wide range of academic influences on five key research areas, i.e. spatial forms in the information era, spatial effects in the information era, digits and the information city, information technology and tourism, residential behaviors and activities in information era and so on. It is prospected that geography and information technology (IT) will be combined deeply in the coming new mobile information era. In the future, it needs to strengthen the empirical researches of Information Geography on the social culture and the humanities further. Five latest trends are also proposed for Information Geography in Nanjing University: 1) Urban space under the deep influences of information technologies, including the new spatial forms of production space, consumption space, social and cultural space, recreation and leisure space under the influence of IT. 2) Behavior geography and mobile IT, including the influences of IT on residences, trips, livings of residents. 3) IT and tourism geography research, including the management of tourism industries, influences on decision-making before tourists’ travel and so on. 4) Smart city and mobile IT, including the transformations of city management and city governance in the mobile IT. 5) Geographical responses to the internet of things, focusing on new empirical studies compared to the concepts of the traditional space, location, spatial interaction, spatial structure and behavioral models.
运用集中度和集中期、Kendall秩相关系数、R/S分析法、降水—径流双累积曲线模型及其他数理统计方法,分析了金钱河流域径流的变化特征,探讨了年际、季节及月尺度上径流变化的趋势并预测了未来趋势,用集中期指标反映了径流对降水响应的滞后效应,并定量分析了降水变化和人类活动对径流变化的贡献率。结果表明：50 a来径流量呈现出显著的递减趋势（p<0.05）,递减率为34.33 m3/（s•10a）,Hurst指数H=0.669>0.5,表明未来的一段时间内变化趋势与现在相同;1~12月各月径流均表现为下降趋势。流域内径流对降水的响应存在滞后效应,50 a径流对降水平均每年滞后23.6 d,且滞后天数具有明显上升趋势。50 a来径流系数呈极显著减小趋势,降水量转化为径流的部分在逐年减少,被植物截留、填洼、入渗和蒸发的部分增加;径流发生突变后比突变前径流系数降低了35.2%。50 a来降水变化对径流变化的影响率为53.4%,高于人类活动影响率46.6%,是导致径流变化的主要原因,人类活动为次要原因。
The response of river water resource to both human activities and climate changes, as the theoretical basis to understand the river hydrological process and the sustainable use of regional water resources, has gained more and more attentions in water research during the last decades. In this study, the seasonal and annual variations and the temporal trend of runoff in Jinqian River Basin were analyzed by using the methods of concentration frequency,concentration period, Kendall coefficient, rescaled range analysis and double mass curve for annual rainfall stream flow comprehensively, in which the runoff and precipitation lagging effect was represented by concentrated period index. The effects of the precipitation change and human activities on runoff were also analyzed quantitatively. The annual runoff of Jinqian River is mainly contributed by those occurred from July to October with a proportion of 65%. Regression analysis showed that the Jinqian River’s runoff decreased with time at a rate of 34.33 m3/（s•10a）significantly (p<0.05). The Hurst index was 0.669, which indicates that the decreasing trends of runoff in Jinqian River’s will continue in the future. There is an around 23.6 days hysteresis in the response of runoff to precipitation, and the hysteresis has obvious up trend. Through the annual runoff coefficient, It was found that the runoff from rainfall decreased with the time due to plant interception, infiltration and evaporation during last 50 years. Human activities and climate change both had significant impacts on the water resource of Jinqian River. The result of double mass analysis showed that the decreases of runoff in Jinqian River’s mainly attributed to climate change, and its contribution were 53.4%.
：In GIS, vector data is the most commonly used data structure. Data compression is an issue in vector data processing and applications. In this paper,several commonly used algorithms of vector data compression are analyzed and a new efficient algorithm is proposed to resolve the problems of the classic algorithms. The Douglas-Peucker algorithm and the vertical distance tolerance algorithm are commonly used algorithms in vector data compression.The Douglas-Peucker algorithm have the advantage that it has invariance in translation and rotation, but at the same time the result has a big area error and there is a contradiction between the compression ratio and retention of feature points for the curvature change. The advantages of the vertical distance tolerance algorithm is fast, but the area error and the characteristics of the retention curve space are very poor. In this paper,a new algorithm is proposed which improved vertical distance tolerance algorithm and resolved the shortcomings of the Douglas-Peucker algorithm and the vertical distance tolerance algorithm.The basic idea of the new algorithm is based on the vertical distance tolerance algorithm which increase an area error tolerance by adopting the method of straight line fitting to approximate the axis of the polyline in order to resolve the problem of the area error and declination of segment in space. An experiment is included, which verified the new algorithm is efficient by the example of dealing with the boundary contour vector of Chongming Island, Shanghai. In the experiment ,the new algorithm has only 1 km2 error, but the classic algorithms has 6 km2 of the error. The most advantage of the new algorithms is that the area error can be controlled in a specified range. The experiments show that comparing with the two classic algorithms,the new algorithm has no substantial advantage in the compression ratio,but greatly improved the performance of two targets, area error and declination of segment in space. It proved that the new algorithm is efficient in the data procession which has high requirement in area accuracy and spatial characteristics such as the use of land resources.
在苏打盐碱土区进行结冰灌溉试验,研究灌溉后盐碱土土壤水分和盐分的分布状况。试验分为淡水结冰灌溉（E）、微咸水结冰灌溉（D）、微咸水结冰灌溉+100%GR（石膏需求量）磷石膏（A）,微咸水结冰灌溉+50%GR磷石膏（B）,以及对照（CK）, 5个处理。灌溉水量为180 mm。试验结果表明灌溉融水增加了土壤耕层的含水量,为春播抗旱起到了重要作用。同时灌溉融水使土壤耕层主要离子Na+、Cl-、CO32-、HCO3-明显降低,使土壤耕层的盐碱化程度得到改善。不同处理方式之间比较,微咸水结冰灌溉洗盐效果和盐碱化改良效果明显好于淡水结冰灌溉,微咸水+磷石膏淋洗和改良效果好于微咸水结冰灌溉,且随着磷石膏施用量的增多,洗盐和改良效果更好。
：A field experiment was conducted to investigate the water and salt dynamic of saline-sodic soil with freezing water irrigation in winter in Songnen Plain of China, which is one of the largest saline-sodic areas in the world. The plots were designed as follows: freezing saline water irrigation with application of phosphogypsum (100%GR gypsum requirement) (A), freezing saline water irrigation with application of phosphogypsum (50%GR) (B), freezing fresh water irrigation (C), freezing saline water irrigation (D), no irrigation and no phosphogypsum as CK. A total of 180 mm water was applied to experimental plots in January of 2011. Results showed that melted ice water increased soil water content in topsoil layer. It has great significance for resisting drought in spring planting. With infiltration of melted ice water, the surface soil was significantly desalinized. Major ions including Na+、Cl-、CO32-、HCO3- were decreasing by melted ice water. Comparative analysis demonstrated that desalinized effect was better in freezing saline water irrigation than freezing fresh water irrigation, and desalinized effect was better in freezing saline water irrigation with application of phosphogypsum than freezing saline water irrigation, and with the increase of phosphogypsum, soil desalinized effect was higher. The results indicated that the approach of freezing saline water irrigation and phosphogypsum in winter may benefit to resist drought in spring planting and improve saline-sodic soil by use of local saline groundwater.
应用SWAT模型对辽宁省大伙房水库汇水区农业非点源污染进行了模拟,利用2006~2009年的水文和水质监测数据对模型进行率定与验证。研究结果表明：研究区泥沙坡面产量为15.40×104 t,属于微度侵蚀,其中耕地的土壤侵蚀模数最高,为475.84 t/(km2·a),疏林地次之,灌林地、有林地的土壤侵蚀模数较小;汇水区农业非点源氮、磷产生量分别为1 248.83 t和102.88 t;不同土地利用类型氮、磷的产生量差异较大,耕地远远高于林地等其他类型。总体上,流域农业非点源污染的产生量浑河流域高于苏子河流域,社河流域最小,且河流上游地区高于下游。研究结果揭示了研究区农业非点源污染空间分布特性,可以为水土保持和非点源污染防治提供基础支持。
SWAT model was used to calculate the agricultural non-point source pollution in Dahuofang reservoir catchment, Liaoning Province. The monitoring data of hydrology and water quality series from 2006 to 2009 was used to calibrate the parameters and validate the model, and the results indicated that SWAT model was appropriate for Dahuofang reservoir catchment. The calibrated model was used to reveal the spatial distribution of agricultural non-point source pollution characteristic. The results show that the annual amount of soil erosion in the reservoir catchment was 1.54×105 t. In other words, there was very light soil erosion in the investigated area. The result was consistent with the actual situation of the forest coverage in this area. The various usage of lands have various degree of soil erosion. The arable lands indicated the highest soil erosion modulus, which were 475.84 t/(km2·a); the open woodlands were the second highest contributor, followed by shrub woodlands, and the soil erosion of the forests were the smallest. The slope output of both nitrogen and phosphorus in catchment were 1 248.83 t and 102.88 t, respectively. The Hun River basin ranked first in the contribution to the load of TN and TP pollution, accounted for 52.01% and 52.43%, respectively, followed by the Suzi River basin and the She River basin. The minimum contributors were the basins around the reservoir. The pollutions of nitrogen and phosphorus were various with different types of land use. The loads of TN and TP were mainly from the arable lands, which were 1 024.33 t and 93.35 t, respectively, which were much higher than the other land use types. Overall, the non-point source pollution around the Hun River basin was higher than the Suzi River′s, while the She River basin was minimum. The output intensity of non-point source pollution of the upstream region was higher than the downstream. This study indicated the spatial spread features of non-point source pollution at target areas, and the results provide a significant support to prevent both soil erosion and non-point source pollution.
黄河三角洲湿地是中国最具代表性的滨海湿地之一,也是中国第二大油田——胜利油田的产油区,石油污染已成为本区湿地生态系统退化的重要因子。在温室条件下模拟研究了该区滨海湿地土壤中2种不同浓度(0.5%、2.0%)石油污染对黄河三角洲地区典型物种芦苇（Phragmites australis）和盐地碱蓬(Suaeda salsa)幼苗生长的影响。结果表明,随着石油浓度的增高,芦苇和盐地碱蓬株高的受抑制程度不断增强,随着时间的推移,石油污染对芦苇分蘖的抑制作用减弱,而对盐地碱蓬幼苗的分枝数抑制作用加大。随石油浓度的增加,盐地碱蓬幼苗叶片中可溶性蛋白质含量先升高后降低,丙二醛含量和过氧化物酶活力先降低后升高,过氧化氢酶活力显著降低;芦苇幼苗则对石油污染表现出相对较强的耐受性。不同石油污染条件下芦苇幼苗叶片叶绿素含量表现出先下降后升高的变化趋势。从整体上来看,石油烃类污染对盐地碱蓬幼苗的抑制作用要高于芦苇幼苗,也说明在处理石油烃类污染物中芦苇比碱蓬更具有优势。
The Yellow River Delta is a typical and representative coastal wetland in China. As the Shengli Oil Field, which is the second largest oil field in China, locates in the region, the crude oil contamination has become a key reason which causes deterioration of coastal wetland ecological system in this area. A simulative study was conducted to explain the effects of different concentration of petroleum (0.5%、2.0%) contaminated wetland soils on growth of reed（Phragmites australis）and seepweed (Suaeda salsa) seedling in the greenhouse. The soil samples without oil pollution were collected in coastal wetlands in the Yellow River Delta of soils in May 2010. The soil oil pollution levels was controlled by three oil concentration (0%, 0.5%, 2.0%) in the simulative experiment in greenhouse, four replicates for each treatment. The crude oil in experiments collected from the Shengli Oil Field production wells. The typical representative plants of reed and seepweed in coastal wetlands in the Yellow River Delta were cultivated in the different soil treatments, respectively. The reed was planted with root with same buds and the seepweed seed was sowed (0.5 g per pot). During experiment period, the seedling height of both reed and seepweeed, tillering number of reed, leaf number and branch number of seepweed were recorded. The soluble protein content, Catalase activity (CAT) activities, peroxidase activity (POD) activities, malondialdehyde (MDA) content, Chlorophyll (Chl) content of seedling leaves were determined, then the ratio of chl-a/ chl-b was calculated. The results showed that, with increasing petroleum concentration, the inhibitory effects of petroleum for plant height of reed and seepweed were increased. The inhibitory effects of petroleum contamination on reed tillering number were weakened with time, while that functions on seepweed branch number were strengthened. With increasing oil concentration in soils, the soluble protein content in seedling leaves of seepweed was decline after increase, while the opposite regulars were observed for MDA content and POD activities, and the CAT activities was decreased obviously. Compared to seepweed seedling, the reed seedling appeared high oil contamination tolerance. The Chl content in reed seedling leaves shows a trend of increase after decline with time under different condition of oil contamination. In generally, the inhibitory effects of soil oil contamination for seepweed seedling were higher than that for reed seedling. It indicated that the reed was much more suitable for restoration of oil contaminated soil than seepweed. Our results suggested that both reed and seepweed with high salt-tolerance properties could be extensively applied in soil restoration of oil contamination regions in the coastal wetland of Yellow River Delta.
针对杭嘉湖地区洪涝灾害日益加剧的现状,基于1960~2007年日降水和日水位资料,采用Spearman检验、有序聚类分析和线性模拟方法,研究了近50 a来降水和水位变化,在此基础上探讨了降水和人类活动对特征水位变化的贡献率。结果表明,区域近50 a降水变化未见明显趋势,水位呈增加趋势,年最高水位、年平均水位和年最低水位增率分别为0.03 m/10a、0.05 m/10a和0.09 m/10a,且平均水位和最低水位增加达到显著性水平。8个代表站点特征水位均呈增加趋势。空间上沿水流方向,线性坡度值增大。水位降水响应率和平水年水位序列分析显示人类活动是水位变化的重要原因。人类活动对最高水位、平均水位和最低水位变化的贡献值分别为39.0％、56.2％和82.9％。
With the gradually increased flooding on the Hangzhou-Jiaxing-Huzhou plain, this paper analyses the problems involved in the changes of water levels of the hydrological system of this region. As one of the most developed regions in China, the plain is undergoing fierce urbanization process. Based on the daily precipitation and water level data from 1960 to 2007 of Hangzhou-Jiaxing-Huzhou plain, the changes of precipitation and water level time series were analyzed by using linear-regression method, Spearman test, and orderly clustering analysis. Then the contribution rate of precipitation and human activities on water level changes were assessed by normal precipitation years and linear simulation methods. The results showed that the trend of precipitation of regions was no significant, while the water level of the regions was increased. Annual highest, average and lowest water level of the region were increased by 0.03 m/10a,0.05 m/10a and 0.09 m/10a, respectively. And the increase of average and lowest water level of the region reached the significant level. Moreover, the time series of water levels of eight representative hydrologic stations were analyzed. The results showed that most of the water levels of representative hydrologic stations were increased. The trend of all annual lowest water level series was significant, and trend of annual average and highest water level in some stations were significant by Spearman test. In space, along the flow direction, linear trend value of the time series were increased by Kriging interpolation. At last, the reasons for the changes of water level were evaluated. The highest, average and lowest annual water level of the region in normal precipitation years before and after the cut-point were increased by 10.67%, 8.17% and 42.95% respectively, while the precipitation was decreased by -1.06%. The contribution rate of human activities on the changes of the highest, average and lowest water level ??were 39.0%, 56.2% and 82.9% respectively. Human activities were the important cause to water level changes, particularly, to annual lowest water level. The results of this paper will be helpful for the water resources management of the urbanizing plain river network region and sustainable development of society and economy under the changing environment.
利用1948~2009年美国环境预报中心 (NCEP)500 hPa高度场逐日再分析资料, 按照通用的阻塞高压天气学定义,采用机器自动识别方法,检索和分析近62 a亚洲夏季阻高活动时空变化特征,结果表明:共统计到1 337个阻塞高压个例,以生命期3~7 d的过程居多,占80.1%,阻高活动累计个数和累计天数集中区可分为偏东类（鄂霍次克海）、偏西类（乌拉尔山）、中间类（贝加尔湖）和其他类4类,其中中间类阻塞高压活动累计个数最多,占总个数的30.4%,偏东类次之,占27.5%,其他类占23.8%,偏西类最弱,占18.3%;20世纪90年代以来,乌拉尔山地区阻高处于明显偏弱期,鄂霍次克海阻高处于偏强期;但是,21世纪初叶,乌拉尔山地区阻高活动开始呈上升趋势,而鄂霍次克海阻高却呈明显下降趋势,值得关注;夏季阻塞高压与东北冷涡活动天数呈显著同期正相关,与长春、哈尔滨同期平均气温呈显著负相关;亚洲夏季阻塞高压是影响东北夏季低温重要的环流系统;鄂霍次克海阻高6月活动异常年,850hPa风距平场在120° E ~140°E,40°N~55ºN存在很强的偏东气流,有利于来自鄂霍次克海偏东北路径的冷空气入侵东北亚及中国东北地区。
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 21st 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.
应用近49 a东北地区200个气象站冬半年降水资料和相对应的NCEP/NCAR 2.5º×2.5º温度场再分析资料,提出了基于降水相态变化特征的东北地区暴雪天气划分的统计学方法,将东北地区暴雪分为纯雪型暴雪（Ⅰ型暴雪）和雨雪混合型暴雪（Ⅱ型暴雪）两大类,并根据影响范围将其划分为大范围暴雪、区域暴雪和局地暴雪3类。在此基础上分析了不同类型东北区暴雪的时空分布特征。结果发现：两型暴雪出现频次基本相当, Ⅱ型大范围暴雪明显多于Ⅰ型,局地暴雪则相反;东北地区暴雪的年际变化较大且具有明显的年代际特征,20世纪70年代后期至80年代中期Ⅰ型暴雪明显多于Ⅱ型, 21世纪初期Ⅱ型暴雪多于Ⅰ型,表明全球变暖在中国东北的区域响应显著;东北区暴雪主要集中在秋末和初春两季,但两型暴雪起止时间和峰值都不相同;两型暴雪出现频次都呈东多西少的分布,其中Ⅱ型暴雪频次自东南向西向北减小的梯度更大。从结果来看所提出的划分办法很好的反映了不同降水相态的东北地区暴雪的发生和变化规律具有很大差别,这种差异与以往东北地区暴雪个例的分析工作中反映的情况是一致的;证明了本划分方法是合理的,具有实际工作意义。
By using precipitation data of 200 stations in the winter half Year (from October to next May) in Northeast China and NCEP / NCAR temperature reanalysis data with a horizontal resolution of 2.5o×2.5o, a classification of snowstorm events in Northeast China is proposed based on phase features of water content in the precipitation . The snowstorm events can be grouped into two categories: one with only pure snowfall (Type I ) and the other with snow and rain mix ( Type II ). And each type can be further classified into three groups, namely, extensive, regional and local range according to the area affected. On this base, the spatial and temporal characteristics of different types of snowstorms in Northeast China are studied. It is showed that the two types bear basiclly the samef requency of occurrence, however, with respect to extensive-range events,the type II is much more frequent than the typeⅠ, while for local snowstorms the situation is reversed. There are substantial interannual variations of the snowstorm events in Northeast China , and the interdecadal characteristics are also obvious. The frequency of type Ⅰwas significantly higher than type Ⅱ during the late 1970’s to the mid 1980’s, and the reverse appeared in the beginning of 2000’s, which might imply the response of climate in Northeast China to the global warming. Snowstorms in Northeast China mainly occur in late autumn and early spring, but the timing of their beginning, ending and peak of activity are different for the two types . The frequency of snowstorm decreases from the west to the east for both types, but the decrease is even sharper from the northwest to southeast for the type II events. The results suggest the classification approach proposed well reflects the difference of two types of snowstorm process in Northest China in terms of their spatio-temporal variations . The results are also in agreement with previous case studies ,which may justify, to some extent, the rationality of the method proposed, and its usefulness for the coming practical works.
利用丰满流域水文站1936~2008年降水资料、1948~2008年美国国家环境预报中心（NCEP）再分析资料,通过线性趋势分析、小波分析、M-K检验分析和最大熵谱分析对该流域汛期降水量变化特征进行了分析。结果表明：丰满流域汛期降水量与年降水量均呈减少趋势,特别是近20 a和30 a降水量减少较明显,汛期降水量下降趋势倾向值在1989~2008年达到-39.2mm/10a;年降水量下降倾向值在1979~2008年达到-26.5mm/10a,汛期降水量的减少较年降水量减少的明显。汛期6月、7月降水量下降的不明显,8月、9月降水量减少相对明显。最大熵谱分析和Morlet小波分析结果表明,丰满流域汛期降水量的周期变化存在着一个8~9 a左右的降水相对短周期和一个28 a的降水长周期;利用1948~2008年NCEP再分析资料对多雨、少雨的7月、8月200 hPa、700 hPa环流形势场、850 hPa风场进行了分析,以分析流域汛期降水减少的可能原因。丰满流域降水减少的可能原因是汛期影响该流域的台风次数减少、冷涡影响天数的减少,副高偏南、偏西不利于水汽向北输送和南支系统北上的影响。
By use of the precipitation data from hydrological station at Fengman basin in 1936-2008, as well as the reanalysis data from National Center for Environmental Prediction (NCEP) in 1948-2008, the characteristics associated with the precipitation variation in flood season at this basin were discussed by means of linear trend analysis, wavelet analysis, M-K analysis and maximum entropy spectrum analysis. The results show that, both the total amounts of precipitation at flood season and the whole year are decreased with time in Fengman basin, especially in the recent 20 and 30 years. The precipitation at flood season decreases more than the annual precipitation, for the precipitation decrease trend values in flood season reach -39.2 mm/10a from 1989 to 2008, but those of annual precipitation are only -26.5 mm/10a from 1979 to 2008. The total amounts of precipitation decrease sharply in August and September, while little in June and July during flood season. Results from analysis of maximum entropy spectrum and Morlet wavelet show that, there are two kinds of precipitation cycles in flood season at Fengman basin. One is the relative short cycle with eight to nine years, the other is the long cycle with twenty eight years. In order to study the possible reasons about the decrease trend in flood season at Fengman basin, the circulation fields in 200 hPa and 700 hPa, and the wind fields in 850 hPa were analyzed by use of the NCEP data from 1948 to 2008. It shows that, the main reasons about the decrease trend in flood season at Fengman basin are the co-effects of the reduced amounts of Typhoon and the days of cold vortex in Northeast of China affecting this basin, as well as the unfavorable condition for water vapor conveying northwards as the subtropical high is more southerly and westerly than usual, and the northward movement of the weather systems on the south.