Table of Content

05 July 2016, Volume 36 Issue 4 Previous Issue    Next Issue

Whose Heritage?—A Comparison between Nonlocal and Local Tourism Business’s Heritage Identities in the Yuanyang Terraces Area QU Ce，ZHANG Chaozhi 2016, 36 (4):  524-531.  doi: 10.13284/j.cnki.rddl.002868 Abstract ( )   PDF (327KB) ( )   Save In order to discuss the basic question, “whose heritage”, from the perspective of heritage identity dissonance, this paper collects network text, images and field interviews of the Inn operators in Yuanyang terraces area, and then with the discourse analysis compares the differences between the heritage identities of the local and nonlocal operators. The findings show that the interpretation and communication of heritage for the middle class of nonlocal operators are diversified, cross-cultural and petty. They attach great importance to the heritage display and spreading, and consider that the heritage is “theirs”. But to the scale of “home” and local “place” they do not think the heritage area is their home and just regard themselves as outsiders. To the scale of nation and world, they believe that the heritage belongs to “our human beings”. Instead, the negative attitude toward the farmer identity of local operators leads to their heritage landscape elements being abandoned and hidden. However, to meet their need of tourism benefits, some local operators begin to be aware of the heritage display. Therefore, the heritage is not “ours” in the eyes of the farmers. But to the scale of “home” and “place”, the local operators believe the heritage is “ours” and worthy of attachment. Otherwise, they have no salient cognition of the scale of nation and world. Based on the above, the paper has some discusses about heritage protection and management. References | Related Articles | Metrics

Analysis on the Sense of Place and Rice Terrace Protection in the World Heritage Site of the Honghe Hani Rice Terraces HUA Honglian，ZHOU Shangyi，JIAO Yuanmei，WANG Mei，HU Zhixin 2016, 36 (4):  532-538.  doi: 10.13284/j.cnki.rddl.002867 Abstract ( )   PDF (495KB) ( )   Save There is growing concern about the role of sense of place in the process of heritage protection, most of the existing literatures focus on the personal sense of place and the effects on heritage protection, but think little about the role of natural and social environment in the formation of sense of place. Based on the findings in some international literatures and the characteristics of the human-environment relationship of Hani Rice Terraces, this research constructed a Structural Equation Model (SEM) that composed of four variables - nature bonding, social bonding, sense of place and awareness of terrace protection, trying to find the interaction between the sense of place and the other three variables. The results show that the connectedness with nature, nature attachment, the kinship, neighborhood, and activities in community have significant effect on sense of place, and there is a positive correlation between sense of place and awareness of terrace protection. In addition, social boding is also a direct and significant contributor to awareness of terrace protection. The results further validate that sense of place has positive influence on environmental concern and support the assumption which supposes that the intrinsic characteristics of a place and the bonding between people and those characteristics play an important role in forming sense of place. According to these results, we consider that traditional and important festivals should be taken to reinforce the traditional organization mode in community society and the traditional system of natural resource management and allocation should be cemented, so as to enhance the internal motivation for Hani Rice Terraces conservation. References | Related Articles | Metrics

Demands of Middle School Students for Environmental Interpretation of Cultural Landscape Heritage of the Honghe Hani Rice Terraces LIU Zhilin，JIAO Yuanmei，WANG Mei，DING Yinping，YAN Xiaojing，ZHANG Kaifeng，LIU Xin 2016, 36 (4):  539-547.  doi: 10.13284/j.cnki.rddl.002870 Abstract ( )   PDF (183KB) ( )   Save Taking the middle school students who live in the center part of Honghe Hani Rice Terraces heritage area as study subjects, this paper analyses their demands of environmental interpretation by questionnaire survey. The results show that: Firstly, among the three parts of the contents of environmental interpretation, the order is as knowledge>awareness>skills, which vary with the variety of gender, grade, and location, revealing that the students are in great needs of the content of environmental interpretation and there is significant difference among the students in different backgrounds; Secondly, in term of activities and patterns of environmental interpretation, the middle school students are more in needs of firsthand experience, spots commentary, field studies and local festival activities than the ways of interpretation boards, internet and leaflets, which vary with the variety of gender, grade and residential information, indicating the difference in demands for interpretation media, patterns and the correlation with social backgrounds. In conclusion, there are obvious needs of the environmental interpretation among the middle school students in the heritage area, especially of firsthand experience and field trips, therefore the interpretation for them should be mainly taken in way of participation. References | Related Articles | Metrics

Temporal-spatial Distribution and Statistic Analysis on Inscription Standard of Cultural Landscape Heritage HU Zhixin，JIAO Yuanmei，HUA Honglian，WANG Mei，ZHANG Guiling，ZHANG Guo 2016, 36 (4):  548-555.  doi: 10.13284/j.cnki.rddl.002871 Abstract ( )   PDF (1559KB) ( )   Save The exploration of world cultural landscapes is a process that tries to discover the harmonious relationship between human beings and the environment. Cultural landscapes have always been favorably perceived by society but only in 1992 have been formally acknowledged as world heritage by UNESCO. From 1992 to 2013, 85 cultural landscape heritages belonging to 54 countries have been listed as world cultural landscapes during those 20 years. This paper collects information of cultural landscape heritage sites from UNESCO’s official website, analyzes the spatial and temporal distribution, evaluation criteria and heritage’s type of such sites. The results are as follows: 1) The amount of cultural landscape heritage sites keeps increasing steadily since 1992 and the European growth trend is similar to that of the world, but Asia still has much potential;2) The cultural landscape heritage sites are mainly located in developed countries at mid-Northern latitudes, where appropriate climate provides ideal conditions for living. In the global political and economic culture partition,cultural landscape heritages in European and American area account for more than 50% of the total in the world,and those in Europe countries account for about half of the world, Asia is the second, the main legacy superpowers are Italy (6 items), France (5 items), the UK (4 items) and Germany (4 items), China also have 4 items; 3) The 85 heritages are conformed to the evaluation standard mostly on iii, iv and v. It shows that evaluation of the cultural landscape heritage focuses on the continuous evolution; 4) According to the conception of cultural landscape heritage’s type defined by the UNESCO, 51 heritages with clearly identified types that mention in their nomination paper have been counted, of which the organically evolved landscape types account for 60%, being the most hot types. 5) The world cultural landscape heritage will increase and relatively keep balance in spatial distribution in the future, China will get more opportunity to declare. Re–classification of cultural landscape heritage types will facilitate the submission and protection of them. References | Related Articles | Metrics

Construction of Residential Landscape in Tourism Destination Morphology Evolution of Tourism Localization: A Case Study of the Hani Mushroom Houses Based on Local Oral History TANG Guorong，ZHANG Jinhe，SUN Jinkun，PENG Hongsong，ZHANG Yu 2016, 36 (4):  556-563.  doi: 10.13284/j.cnki.rddl.002859 Abstract ( )   PDF (1533KB) ( )   Save The impact of tourism on the evolution of landscape patterns of traditional houses, is an important topic in current regional tourism culture research. Taking Hani mushroom houses in Qingkou, Yuanyang, Yunnan, as a case, this paper uses the method of local oral history to derive the construction mechanism of local tourism interpretation of Hani mushroom houses. The results are as follows: 1) there exist morphological differences in the three stages of the evolution of the local characterization of Hani mushroom houses. 2) the tourism localization is the process of local style reconstruction when the locality features are threaten to be weakened, during which the main bodies such as resources, power, capital and knowledge play the functions of mechanism, image and knowledge construction effect, and the interaction force among the main bodies gives impact on the main direction of residential morphology derivation. 3) during the process the relation between the dwelling environment demands and the localization construction of the tourism place should be in harmony, and the situation beyond locality in the tourist place should be avoided. References | Related Articles | Metrics

Value Cognition of Cultural Heritage Based on Landscape Units:A Case Study of the Watchtowers and Villages in Kaiping LIANG Xiongfei，YIN Jie 2016, 36 (4):  564-571.  doi: 10.13284/j.cnki.rddl.002869 Abstract ( )   PDF (9215KB) ( )   Save Value cognition has been an important prerequisite for the identification, conservation and utilization of cultural heritage. In this paper, value cognition of cultural heritage based on landscape units was explored taking the world cultural heritage site of Kaiping as a case. Firstly, a cultural heritage database was set up and landscape units were constructed based on the spatial and functional characteristics of cultural heritages. Secondly, the types and characteristic of landscape units are screened by evaluating the internal elements of landscape units and using the clustering method. Three types of defense landscape units were obtained: inland-defense landscape units,village joint defense landscape units, and thoroughfare defense landscape units. Finally, the spatial distribution of the various types of landscape units was investigated using the superposition method; the value system of landscape was clarified; and it was suggested that typical inland-defense landscape units be additionally screened to carry out cultural heritage integration conservation from the perspectives of type integration and element integration. References | Related Articles | Metrics

Symbolic Space and Formation Process of the Licha Village in the Zhaoqing City REN Bingxun，YANG Ying，LIN Lin 2016, 36 (4):  572-579.  doi: 10.13284/j.cnki.rddl.002856 Abstract ( )   PDF (5306KB) ( )   Save The Licha Village of the Zhaoqing City mainly experienced a start-up phase, a prosperous phase and an overflow phase. From the perspective of symbolic space, the cultural landscape symbols of the Licha Village was analyzed as a whole and from inside. The results showed that: the Licha Village was built according to the terrain and around waters with an outline similar to the shape of the Eight Diagrams, consisting of “fifty houses and one street”. The central symbolic space evolved from the initial “Well of the Zhou family and Delonix” to “one platform and four wells” and now expanded to the whole ancient village; the Ground Hall was a symbol of the family status; the Wine Hall was a symbol of parties and activities; the Ancestor’s Hall was a symbol of family inheritance. The Licha Village formed making use of the opportunities brought by the land policy change, was driven and improved by the traditional culture, adapted to and was transformed by the natural environment and was driven by the needs of defense. References | Related Articles | Metrics

Construction Mode of Traditional Villages’ Human Settlements in Southern Hunan HE Feng，CHEN Zheng，ZHOU Hongwei 2016, 36 (4):  580-590.  doi: 10.13284/j.cnki.rddl.002861 Abstract ( )   PDF (15815KB) ( )   Save As the environmental crisis and energy issues are becoming increasingly prominent and living cultures are constantly convergent, study of construction modes of the traditional villages’ human settlements is important for optimizing rural human settlement and deepening the construction of socialist new countryside. By taking Southern Hunan as geography unit, the location strategies and construction modes of the local traditional villages’human settlements were studied, which were based on the analysis of the natural geographical conditions and historical and cultural environments. Taking defense, agricultural production, economic construction and concepts of Fengshui into consideration, traditional villages in southern Hunan usually were located at sloping fields or platforms of hills where the geographical environment was relatively independent or closed. The construction modes of traditional villages’ human settlements in Southern Hunan included pursuing the philosophy of “harmony between man and nature”, abiding by the traditional etiquette, autonomous, coadjutant, economical and practical principles, reflecting the law of location selection when those villages were developing. References | Related Articles | Metrics

Spatial Pattern of Job-housing Relationship of Polycentric Cities: A Case of Zhongshan City ZHONG Guoping，CAO Xiaoshu 2016, 36 (4):  591-599.  doi: 10.13284/j.cnki.rddl.002858 Abstract ( )   PDF (16962KB) ( )   Save As a “strong periphery, weak center” pattern of polycentric city, the distribution of spatial elements include population, economy, land utilization, and traffic infrastructure show a feature of “large dispersion, small agglomeration”. A resident trip survey was conducted in October 2012 in Zhongshan city. Among the 80,000 samples surveyed, 40 445 are valid and used in this study. 446 TAZ (Traffic analysis zone) of the whole city are all included as spatial units. By using the function of spatial analysis and manual break of ArcGIS, the spatial pattern of job-housing ratio, commuting time, commuting distance, commuting direction of a low density of urbanization and polycentric city was portrayed. Responding to the urban spatial structure, the city's layer structure is not significant. The characteristics include job-housing ratio, commuting time, commuting distance, commuting direction. The job-housing spatial distribution present uniform as a whole, job-housing balance in the main city is more significant. The commuting time and commuting distance of Zhongshan’s residents are much shorter than those of big cities in domestic and in western cities. The ratio of commuting between the main city and the circumjacent towns is very low, the mass pendulum model of commuting flow between periphery and center does not exist. The commuting direction of the city presents that from center city to center city or from circumjacent towns to circumjacent towns. There has a close relationship between spatial pattern of job-housing relationship and those factors, such as city spatial pattern, demographic structure, industrial structure, industrial distribution, land utilization and transportation infrastructure. References | Related Articles | Metrics

Modeling Urban Population Densities in City Integration Areas: A Case Study of Guangzhou and Foshan LI Fengzhen，ZHONG Jianbo，XIE Shiying，LI Xun 2016, 36 (4):  600-609.  doi: 10.13284/j.cnki.rddl.002866 Abstract ( )   PDF (4190KB) ( )   Save This research models the population densities in Guangzhou and Foshan metropolitan area with data from the fourth, fifth and sixth national population censuses. 1) Monocentric population density functions can well describe population density distribution of Guangzhou and Foshan metropolitan area. 2) By applying the population functions, this research describes the population density change in city integration areas. As Guangzhou and Foshan metropolitan area becomes more regionally integrated, the population density in city integration areas is increased. Furthermore, city integration areas within Foshan City are more willing to be integrated into the core area. References | Related Articles | Metrics

Environmental Impacts on Burglary Victimization in Gated Communities: A Multi-level Analysis in Guangzhou YANG Gangbin，LIU Lin，HE Shenjing，XU Chong 2016, 36 (4):  610-618.  doi: 10.13284/j.cnki.rddl.002860 Abstract ( )   PDF (932KB) ( )   Save Based on large-scale household survey conducted during the period from October to December, 2012, in Guangzhou, the authors studied burglary victimization and its environmental leading factors in gated community. The research variables selection of this paper is under the guidance of the CPTED (crime prevention through environmental design) and social disorganization theory. From the perspective of community environment, the paper explores the impact of environmental factors on household burglary victimization. On the basis of literature review, this paper first introduced the core elements and main ideas of CPTED theory and social disorder theory, which are broadly accepted in community crime research. Under the guidance of these elements and ideas, we finished an investigation of gated community in Guangzhou, China. Related social, economic and environmental factors are collected. Principal component analysis and cluster analysis are performed to refine the features of these selected factors. Three main components at community level and four main components at family level were extracted. To check community environment and social-economic factor’s effects on household burglary condition，hierarchical logistic regression was performed to analyze the cross scale effects between community and family factors on family burglary condition. The results of the five multi-level regression models suggest that both the community environment and family housing characteristics have significant impact on residential burglary victimization. Family burglary victimization is mostly affected by family housing conditions and demographic characteristics, while community variables have a very important role in regulating family factor’s effect. Regression results show that housing conditions, public space utilization rate and family population characteristics have significant influence on whether a house is burglarized. Furthermore, neighborhood formal control mechanisms, community environmental image, residence turnover rate, community openness and degree of function mixing through indirect effects of family characteristics have influence on household burglary victimization. References | Related Articles | Metrics

Morphological Characteristics and Origin of Potholes in the Shiduxi River, Jiexi ZENG Lanhua，CAI Jincheng，OU Xianjiao 2016, 36 (4):  619-625.  doi: 10.13284/j.cnki.rddl.002790 Abstract ( )   PDF (8483KB) ( )   Save There were debates about the origin of the potholes in the Shiduxi River, Jiexi, in Geoscience community of Guangdong. In order to get more new evidence for that issue, the authors investigated the potholes in the river with new measuring and statistical methods proposed in recent years. The morphological characteristics of 232 potholes were measured in detail and were statistically analyzed. Results show that the potholes are distributed across the streambed profile without clear regularity in size, depth and shape. Most of the potholes are elliptical or elongate, and develop along the rock joints. The strikes of the potholes are consistent with the main joint and the valley trend. In some of the potholes, striation and debris can be respectively seen on their walls and bottoms. Origin and development of pothole are influenced by multiple factors such as lithology and geological structure of streambed rock, gradient and fluvial action. Joints play a particularly important role on pothole origin and development. Potholes are created by runoff erosion and are irrelevant to glaciation. They commonly develop in the rocky streambed of mountain rivers with certain gradient, rapid-flow stream and appropriate joints. References | Related Articles | Metrics

Evaluation of Drainage Capability of Urban Pipelines TANG Qinghua，HE Peiying，ZHU Zhihua，ZHANG Mingzhu，LIU Hao 2016, 36 (4):  626-632.  doi: 10.13284/j.cnki.rddl.002862 Abstract ( )   PDF (9671KB) ( )   Save Based on measured precipitation and runoff data of the residential district in Guangzhou, China, this paper simulated the drainage capability of pipe network under different return period in resident district using calibrated SWMM. The results suggest that when faced with two years’ return period rainstorm, water would accumulated at Nodes J14, J15 and J31, and water accumulation would become more serious with increasing return period. When faced with five years’ return period rainstorm, accumulated water amounts at Nodes J15 and J31 were 1674m3 and 546m3, respectively, and accumulated water times were 0.5h and 0.4h, respectively. In view of low pipe drainage capability in our country, this paper suggested using LID measures to reduce peak flow of storm flood, so as to improve the existing drainage capability of the network. This paper built an assessment method of drainage capability for the existing urban pipe network, which not only could identify the main water spots and pipe flow section, but also could provide a dynamic, qualitative and quantitative evaluation of the ability of the drainage pipe network. References | Related Articles | Metrics

Empirical Vulnerability Functions of Building Contents to Flood Based on Post-typhoon（Fitow, 201323）Questionnaire Survey in Yuyao, Zhejiang MO Wanmei，FANG Weihua 2016, 36 (4):  633-641.  doi: 10.13284/j.cnki.rddl.002828 Abstract ( )   PDF (6847KB) ( )   Save Vulnerability, which quantifies the loss ratio under different hazard intensity, is an important feature of the natural disaster system. However, its estimation is hampered by the lack of loss data of actual cases. To investigate the building content loss due to Typhoon Fitow, we first introduced the concept of flood vulnerability curve and its secondary uncertainty analysis, designed and distributed the questionnaire and collected 386 valid responses, and then analyzed how the loss ratio increased with the water depth based on the survey data. Finally, we fitted eight flood vulnerability curves for building contents using the Logistic function, and quantified their secondary uncertainties using the Beta function. This study reveals that the lower-income households or commercial tenants are more vulnerable to the typhoon disasters. The mean damage ratio of the contents increases with the increasing water depth, which can be generally divided into three stages according to the growth rate. However, the uncertainty within the vulnerability curves arises from many sources. Thus, the secondary uncertainty distribution of the loss ratio which is more dispersed in the second stage varies in different segments of water depth. The correlation between loss ratio and flooding duration is not statistically significant in terms of this questionnaire survey data. The results can effectively describe the flood vulnerability for building contents in Yuyao city of Zhejiang Province so as to provide the input to post-disaster loss assessments and catastrophe modeling applications. References | Related Articles | Metrics

Chemical Composition and Sources of the Artificial-Harvesting Dew Water at the Shipai Campus, South China Normal University, during the Spring of 2013 WEN Xiaohao，JI Yixuan，WU Hang，WU Yijie，ZHOU Jiaming 2016, 36 (4):  642-648.  doi: 10.13284/j.cnki.rddl.002791 Abstract ( )   PDF (842KB) ( )   Save During the spring of 2013, for investigating the atmospheric environment, 52 samples of “artificial-harvesting dew water”, which was the dew artificially condensed from vapour, were collected at the Shipai campus of South China Normal University in Guangzhou. The measurement of pH values and ion concentrations of the samples shows that: 1) most of the samples had pH values ranging from 5.00-6.47 with an average of 5.97, indicating they were not of severe acid rain status; 2) The ion concentrations (μeq/L) of the samples in a decreasing order was 2-4 SO > Ca2+> 3 NO? > Na+> Cl-> 2 NO? > Mg2+ ≈ K+> F-. The range of total ion concentrations (TDS) was from 57.87-484.38 μeq/L with an average of 154.53 μeq/L. The characteristics of such pH values and ion concentrations indicate that the degree of cleaning was equal to that of the samples of atmospheric precipitation collected in Heshan (Guangdong Province) and Waliguanshan (Qinghai Province), and was better than that of the samples of atmospheric precipitation collected at the Shipai campus of Guangzhou and at a campus of Shanghai in the spring of 2011, but it was worse than that of Lijiang (Yunnan Province). The pollution sources were mainly anthropogenic ones, such as the airborne dust of building, combustion of coal and oil, etc. References | Related Articles | Metrics

Grain Size Characteristics and Sources Identification of Foliage Dust near Pedestrian Bridges in Guangzhou ZHENG Yanming，LI Jiancheng 2016, 36 (4):  649-657.  doi: 10.13284/j.cnki.rddl.002865 Abstract ( )   PDF (7701KB) ( )   Save Samples of urban dust deposited on leaf surfaces near 36 pedestrian bridges in Guangzhou in 2009 were measured to determine their grain size characteristics. The result revealed that the foliage dust was mainly composed of sandy silt, with silt volume content accounting for 53.99%, sand volume content for 41.34%, and clay volume content for 4.67%; Grain size frequency distribution showed three peaks, the main kurtosis lay between 10~200 μm. Grain size characteristics of the foliage dust in the 4 districts were very similar, that showed that as a whole of Guangzhou city, the causes and sources of the dust were relatively consistent. TSP (≤100 μm) content was high in the foliage dust, and PM2.5 and PM10 volume content slightly lower; the ratio of PM2.5 and PM10 was 0.36, indicating the pollution sources were presumably more from local road dust and construction dust. Moreover, study on aeolian dynamics of the foliage dust indicated that its source mainly came from suspended particulate matter within a short range of 30 km around the urban area, which belonged to the endogenous particles. References | Related Articles | Metrics

Sap Flow Characteristics of Cinnamomum Camphora,a Subtropical Evergreen Tree Species LUO Zidong，GUAN Huade，ZHANG Xinping，LIU Na，ZHANG Cicheng，YAO Tianci 2016, 36 (4):  658-665.  doi: 10.13284/j.cnki.rddl.002838 Abstract ( )   PDF (1533KB) ( )   Save In this study, the heat pulse sap flow sensors were applied to investigate the stem sap flow of Cinnamomum camphora in the central south China from April to October of 2013 and from July to November of 2015. The measurements of microclimatic variables (solar radiation, rainfall, air temperature, relative humidity and wind speed) were also conducted in the two study sites. During the year 2013, a severe drought occurred in July and August. The aims of this study were to analyze the variation of daily sap flow velocity and seasonal characteristics and response of sap flow to different environmental conditions. The results show that daily course of sap velocity exhibited mono-peak patterns during sunny days. Daily peaks of sap velocity were notably different in different seasons, they were ranked as summer > spring > autumn > winter. The width of peak values changed against seasons with a narrow-wide-narrow pattern. Nighttime sap flow was also found for Cinnamomum camphora especially obvious during growing seasons. This was likely associated with an enhanced vapor pressure deficit during night, but more reasons that whether nighttime transpiration or water recharge caused nighttime sap flow need further studies. The starting time of sap flow was the earliest in summer, while the latest in winter. The ending time that sap flow reached very low values in nighttime was 1-2 hours later in summer than in winter.These seasonal differences were consistent with variation of solar radiation, time of sunrise and sunset during different seasons. Sap flow ratio of morning over afternoon also varied over seasons with a mean value of 0.74, but all values were smaller than 1.0. This ratio was higher in summer and autumn than in winter and spring. Under different weather conditions, this study analyzed the responses of daily sap flow to sunny days, cloudy days and rainy days. A significant difference appeared in daily sap velocity and flow rate, showing a sequence as sunny days > cloudy days > rainy days. During the summer drought of 2013, a dramatic decrease in sap flow was accompanied with an increase of temperature and vapor pressure deficit. Daily peak sap velocity declined by ~ 95% and the total flow rate during the drought decreased by ~47.8%, as compared with total flow rate in the same time of 2014. Flow rate showed a significant positive correlation with temperature and vapor pressure deficit under no drought conditions while a significant negative correlation between flow rate and temperature and vapor pressure deficit during the summer drought in 2013. Decreasing sap velocity and flow rate during drought indicated an efficient adjustment of Cinnamomum camphora for saving plant water use. References | Related Articles | Metrics

Long-term Variation of Daily Global Solar Radiation and Influencing Factors in the Hainan Island LI Maofen，LI Yuping，LUO Wei，LI Hailiang 2016, 36 (4):  666-672.  doi: 10.13284/j.cnki.rddl.002836 Abstract ( )   PDF (3645KB) ( )   Save In order to investigate the variation of global solar radiation (Rs) and its cause in Hainan Island, long-term daily global solar radiation and routinely meteorological data such as daily sunshine hours, maximum and minimum temperatures at Haikou and Sanya stations were used. Climate tendency rate and Mann-Kendall test were used to analyze the annual, rainy season and dry season variations of daily Rs. Multiple linear regression was implemented to analyze the meteorological factors that influencing the variations of daily Rs. The results indicated that the climate tendency rate was 0.021、0.004、0.038 MJ/m2 for daily Rs of full year, rainy season and dry season at Haikou during 1961-2013, respectively. While the climate tendency rate was -0.68, -0.658, -0.714 MJ/m2 for daily Rs of full year, rainy season and dry season at Sanya during 1993-2013, respectively. The variation of daily Rs presented a fluctuation trend. The “dimming” appeared in 1975-1992, 1975-1990 for Rs of full year and rainy season at Haikou, respectively. Whereas the daily Rs for dry season decreased first and then increased, the “dimming” was in 1967-2003, and the “brightness” was after 2003. And the significant “dimming” was 1995 and 1988-1989.. The daily Rs for full year, rainy season and dry season at Sanya has presented a decline trend since 1993. The obvious “dimming” was in 1999-2013, 2000-2003 and 2009-2011, 1996-2001 and 2004-2013, respectively. The jump year were 1997, 1995 and 1995, respectively. In general, the Rs resources of Sanya were more abundant than that of Haikou. Sunshine duration was the mainly cause of daily Rs variations at Haikou and the Rs for full year, rainy season of Sanya. However, the daily average temperature was the main reason for daily Rs variation of dry season at Sanya. References | Related Articles | Metrics

Comparative Analysis of Three Lightning Parameterization Schemes in WRF Model SHI Dongdong，YANG Zhongjiang，XIANG Chunyan，YANG Hu，XU Yongbin 2016, 36 (4):  673-681.  doi: 10.13284/j.cnki.rddl.002846 Abstract ( )   PDF (10694KB) ( )   Save A squall line that occurred in Jiangsu Province on July 5, 2013, was successfully simulated with the WRF model by using three kinds of lightning parameterization schemes, which were based on empirical formulae.Comparative analysis of different schemes in simulating the distribution and frequency of lightning has beendone. Furthermore, we have discussed the reasons of simulation errors, which lay good foundation for lightningmonitoring and prediction. The results show that PR92w scheme exhibiting the location of lightning is in goodagreement with the observations, but the flash count has certain difference with the actual situation.Coincidentally, the results of PR92z scheme is opposite with that of PR92w scheme. Although forecast in highflash density using LPI is not so correct, it can indicate the distribution of lightning to some extent. Error analysishas revealed that vertical velocity and radar echo are the main factors of influencing the forecast in flash.According to the above results, increasing the grid precision and assimilating radar data is the main approach forimproving the simulation results of PR92 schemes. References | Related Articles | Metrics

Spatial and Temporal Variation of ≥10℃ Accumulated Temperature in the Yangtze River Basin for the Past 40 Years SHI Guangxun，DING Mingjun 2016, 36 (4):  682-691.  doi: 10.13284/j.cnki.rddl.002833 Abstract ( )   PDF (3022KB) ( )   Save Accumulated temperature is an important indicator of regional thermal resources and it deeply influences the growth of crops. As one of China's major grain-producing areas, Yangtze River basin should be closely studied, especially on its spatial and temporal variation of the heat resources for agricultural production.Based on the data of daily average temperature collected from 131 national meteorological stations in Yangtze River basin during the period from 1970 to 2013, the spatial and temporal variation of heat resources (≥10℃) was examined by the linear trend method, cumulative anomaly method, Mann-Kendall (M-K) Test and moving T-test. The results showed that: 1) The stations with earlier time of abrupt change were mainly located in the Midstream River area, the Jialing River basin, the Downstream River area and the Taihu Lake Basin, and the time of abrupt change appeared in 1997; abrupt change in the Minjiang River basin, Tuo River basin, Poyang Lake basin and Dongting Lake basin took place in 2001, the time of abrupt change in the Jinsha River basin was in 2002. 2) The starting date of the daily average temperature (≥10℃) advanced by -1.25, -1.39, -0.8 d/10 a, the ending date of the daily average temperature (≥10℃) delayed by 1.52, 1.43, 1.47 d/10 a, the duration days of the daily average temperature (≥10℃) prolonged by 2.97, 2.92, 4.62 d/10 a, and the accumulated temperature (≥10℃) increased by 113.5, 88.8, 77.3℃/10 a in the northern subtropics zone, mid-subtropical zone and Plateau climate zone, Yangtze River Basin. 3) The annual variations of the accumulated temperature (≥10℃) were differentiated by space. The stations with wider changing range were mainly located in the east side of the line of Hanzhong-Fengjie-Wufeng-Jishou-Wugang, and several individual stations were in the Sichuan Basin,Yunnan-Guizhou Plateau and Qinghai Plateau. References | Related Articles | Metrics

Variation Characteristics and Spatial Differences of Extremely High Temperature Days over South China during the Recent 53 Years CHEN Ying，ZHANG Ling，QIAN Huaisui 2016, 36 (4):  692-699.  doi: 10.13284/j.cnki.rddl.002864 Abstract ( )   PDF (6587KB) ( )   Save Based on the daily maximum temperature data from 56 meteorological stations over South China during 1961-2013, spatial differences of extremely high temperature days over South China were studied by ways of Percentiles, linear trend, Mann-Kendall test and Wavelet analysis. The results show that: 1) Most stations showed a significant increasing trend, especially in coastal areas, the majority entered a rapidly increasing period in the late 1990s, the spatial characteristics revealed a decreasing trend from southeastern to northwestern over South China. 2) Each station experienced a mutation according to Mann-Kendall test, in the 1960s and 1990s most stations showed a significant decreasing and increasing period, respectively, at the 5% level. 3) The first main period of 26 a and 22~28 a existed in average year and each station, respectively, the decreasing and increasing mutations in the period from the mid-late 1960s to the 1970s and in the 2000s or so respectively existed in the multiple oscillation periods, and the main cause of abrupt climate change was the phase superposition of multi-scale oscillation. Spatial differences were closely related to the location of land and sea and terrain according to Mann-Kendall test and Morlet analysis. References | Related Articles | Metrics

Influence of the Yangtze River Droughts on the Exposure Characteristics of the Poyang Lake Wetlands LI Mengfan，ZHANG Qi，LI Yunliang，YAO Jing 2016, 36 (4):  700-709.  doi: 10.13284/j.cnki.rddl.002837 Abstract ( )   PDF (13505KB) ( )   Save The variations in flow regime of the Yangtze River inevitable affect the hydrological condition in the Poyang Lake, and thus affect the spatial pattern of the exposure characteristics of the lake wetlands. In this study,we used a physically based hydrodynamic modeling (MIKE 21) to explore the influence of the Yangtze River droughts on the characteristics of spatial-temporal distribution of exposure area of the Poyang Lake. The objectives were achieved through the comparison of two simulation scenarios. One was the reference case representing for an average condition over a long period of 1953-2000 (marked as S0). The other represented the typical dry year in 2006 for the Yangtze River (marked as S1). Simulation results were assessed for the lake’s recession period from July to December. Results indicated that the Yangtze River drought caused the onset of the exposure of wetland about one month earlier compared to that for the reference case. In 2006, it took only half month to reach an exposure area of 50% of the maximum, which was 1.5 months shorter than that for the reference case. Simulation results also showed that the most significant period affected by the Yangtze River discharge was from August to November. In early August, the expansion of wetland mainly distributed in the Ganjiang delta and the eastern bay of the Poyang Lake. During the period from middle August to November, the expansion of wetland shifted to the northern (downstream) and middle regions of the Poyang Lake. It was found that the flow regime change in the Yangtze River had more impacts on the northern-central parts of the Poyang Lake than the southern (upstream) regions. It was also found that the average wetland expansion rate for 2006 was 25 km2/d, which was 72% more than that for the reference case (14.5 km2/d). This paper was the first attempt to use a physically based hydrodynamic modeling to reveal the interaction between the wetland exposure characteristics of the Poyang Lake and the seasonal flows of the Yangtze River. References | Related Articles | Metrics

Estimation Model for Litchi Leaf SPAD-Reading Based on Hyper-Spectral Data LI Dan，PENG Zhiping，HAN Liusheng，HUANG Jichuan，LIU Wei，HUANG Siyu，CHEN Shuisen 2016, 36 (4):  710-716.  doi: 10.13284/j.cnki.rddl.002764 Abstract ( )   PDF (3028KB) ( )   Save The aim of this study was to analyze the relationship between spectral characteristics of litchi leaf spectra and SPAD reading and to explore the capacity of hyper-spectral data in litchi leaf SPAD value estimation.The relationship between four types of spectral variables and the SPAD values were investigated. The first type was the spectral indices proposed in literature for estimating chlorophyll content. The second was the optimized spectral indices derived by band iteration. The third was the area, location and the slope derived by the red-edge, blue-edge and yellow-edge of the first derivative spectra. The last was the spectral feature variables constructed by the peaks and valleys of the second derivative spectra. The results showed that the slope of blue-edge and the sum of the second derivative spectra in 490-520 nm presented high correlation with SPAD values (the correlation coefficients were -0.834 and -0.856, respectively). For the standard normal variate spectra (SNV), the first derivative spectra (FD) and the second derivative spectra (SD), the four band double difference indices presented the best relationship with SPAD values. The correlation coefficient between (FD516-FD474)-(FD684-FD660) and SPAD values was the highest, which was 0.875. The determination coefficient and RMSE of the prediction model developed by this variable and SPAD values were 0.747 and 2.375, respectively. The result indicated that taking advantage of hyper-spectral data for monitoring of litchi SPAD values would be effective. References | Related Articles | Metrics

Beidou and GPS Integrated High Precision Positioning and Monitoring Analysis of Bridges PENG Zhenzhong，LI Qianxia，XU Zhiqiu，YANG Bo，XIA Linyuan 2016, 36 (4):  717-726.  doi: 10.13284/j.cnki.rddl.002863 Abstract ( )   PDF (7547KB) ( )   Save Global Navigation Satellite System (GNSS) can provide real-time precise positioning services anytime and anywhere so that it is used extensively on deformation monitoring. However, signals of GNSS satellites are easily blocked and interfered by the surrounding like high-rise buildings, people and etc. A large number of infrastructures are located in harsh environment, such as valley, urban canyon and high vehicle - density areas. The availability of satellite positioning in deformation monitoring under the blockage environment was analyzed in this paper. Beidou system has three types of orbits including GEO, IGSO and MEO, which is different from the GPS. Each orbit type has different characteristics, and has different influence on positioning accuracy. Taking Guangzhou Bridge as an example, this paper studied integrated Beidou/GPS precise positioning and positioning with different combinations between GEO, IGSO and MEO. Then, the availability of various positioning was analyzed. Results show that, the accuracy of both Beidou and Beidou/GPS reach millimeter level, which can well meet the demands of deformation monitoring. Besides, Beidou/GPS integrated positioning can increase the number of visible satellites and improve geometric distributions. Since the elevation angles of GEO and IGSO satellites are larger and the accuracy of positioning using GEO and IGSO satellites can achieve 1 centimeter, the availability of GNSS positioning in blockage areas is improved. Therefore, it is hopeful to build an automatic real-time precise system to monitor deformation and disaster at any time. References | Related Articles | Metrics