Table of Content

    29 February 2016, Volume 31 Issue 2 Previous Issue    Next Issue
    Resource Economics
    Differentiation of Regional Economic Effects of Oil Resource Utilization in China
    HAO Li-sha, ZHAO Yuan
    2016, 31 (2):  187-201.  doi: 10.11849/zrzyxb.20150142
    Abstract ( )   HTML ( )   PDF (884KB) ( )   Save
    The efficiency-oriented spatial arrangement of oil resource utilization caused signi-ficant mismatch of the locations of oil production and utilization in China. As the fundamental purpose of oil resources utilization is to promote the overall regional economics rather than to just pursuit the efficiency of resource utilization, this paper measures and compares the regional economic effects of the oil resources utilization in different areas based on input-output tables and two improved and comparable input-output coefficients, which are pulling multiplier and pushing multiplier of added value. The results show that: 1) the differentiation of regional economic effects of oil utilization is less than that of its direct economic effects, suggesting that the utilization of oil resources in each region has promoted the overall development of the regional economy through regional industrial chain; 2) the interactions between regional resource endowments, economic and technological level and the industrial structure are the main factors that impact the regional economic effect of oil resources utilization and its differentiation; in general, either the resource-based industrial structure or the deep-processing-based industrial structure has its advantages in the realization of regional eco-nomic effects of oil utilization, even the regional economic effects in the resource origins are to some extent superior to those in the consumption areas; 3) in the future, China should further improve the regionalization of resource allocation, strengthening the “U” shape distribution of the capacity and level of oil resource utilization among eastern, central and western regions; each region should focus on oil refining in major oil resource origins and oil import ports to take their resources and industrial advantages; besides, in order to take full use of existing oil transport routes and control the resources flow costs, the scale and capacity of oil resources utilization should gradually diminish from the major resource origins or import ports along the main oil transport routes.
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    Quantitative Research of the Impact of Land Fragmentation on Scale Returns of Grain Production—Based on Empirical Data of Yancheng City and Xuzhou City in Jiangsu Province
    GUO Guan-cheng, DING Chen-xi
    2016, 31 (2):  202-214.  doi: 10.11849/zrzyxb.20150178
    Abstract ( )   HTML ( )   PDF (709KB) ( )   Save
    The issue of grain production has always been the focus point of governments and academics. In the paper, we explore the impact of land fragmentation on grain production. Taking the field survey data from farmers in Yancheng and Xuzhou, top two cities of crop yields in Jiangsu Province, as examples, the paper establishes Trans-log function model to weigh the existence of returns to scale. By calculating yield flexibilities of input factors with linear index and logarithmic index of land fragmentation respectively, the paper adds the output elasticity to get the coefficient of returns to scale. Then we get a number which does not differ significantly from 1. The result shows that there is no obvious increasing returns to scale in general when considering the effect of land fragmentation. And the output elasticity of land which is around 0.8 means that land is still the most important factor of production. Furthermore, land fragmentation will do harm to returns to scale of crop production, but it has both positive and negative impacts on grain yield in different regions. So, it is proposed that on the premise of promoting the transfer of rural surplus labor, government should pay more attention to the negative effects of land fragmentation.
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    Quantitative Analysis of Catering Food Consumption and Its Resources and Environmental Cost in Tourist City—A Case Study in Lhasa
    WANG Ling-en, CHENG Sheng-kui, ZHONG Lin-sheng, LIU Xiao-jie, GAO Li-wei, CAO Xiao-chang
    2016, 31 (2):  215-227.  doi: 10.11849/zrzyxb.20150089
    Abstract ( )   HTML ( )   PDF (966KB) ( )   Save
    With the development of the tourism and the improvement of common people's consumption level, the catering industry has become one of important industrial categories in tourist city. The quantitative analysis of catering food consumption and its resources and environmental cost will be helpful to the optimization of food supply model and the sustainable development of catering industry in tourist cities. Based on the field survey data, this paper calculated the total amount of catering food consumption in Lhasa City, a typical highland tourist city. Further, from the perspective of life cycle, the resources and environment cost of catering food consumption in Lhasa was calculated through constructing ecological footprint model. The main conclusions were as follows: 1) In 2011 and 2012, the food consumption per capita was 923.7 g in Lhasa, and the food eaten by people was 780.3 g per capita. There was significant difference between the food consumptions of tourists and local residents. 2) The total amount of catering food consumption in Lhasa increased from 19 498 t in 2006 to 41 506 t in 2013, with 112.9% of increment. Among the total amount of catering food consumption in 2013, local consumers consumed 27 983 t, and tourists consumed 13 523 t. By categories, the food consumption included 9 712 t of meat, 2 843 t of aquatic, 15 696 t of vegetables, 6 034 t of staple food, 4 885 t of fruits and 1 931 t of drinks and wine. 3) In 2013, biological and ecological footprint of catering food consumption in Lhasa was 226 681 hm2, equivalent to 6.3 times of the total cultivated land area of the entire Lhasa. The ecological footprint of catering food waste was 653 hm2 in 2013. Most of the ecological footprint catering food consumption consumed in Lhasa came from outside of the Tibet Autonomous Region, while internal supply of ecological footprint accounted for only 15% of the total ecological footprint. External provinces with a larger share of the supply included neighboring provinces such as Gansu, Ningxia, Qinghai, and some eastern provinces.
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    Resource Ecology
    Spatial Heterogeneity and Individual Differences of Arable Land Use Functions in Peasant Household:A Case Study of Representative Area in Hubei Province
    LI Hai-yan, CAI Yin-ying, WANG Ya-yun
    2016, 31 (2):  228-240.  doi: 10.11849/zrzyxb.20141640
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    Using Hubei Province as a case study, this paper analyzes spatial heterogeneity and farmers' individual differences with modified TOPSIS model. The results indicate that economic contribution is the most significant function of arable land use. It exceeds the functions of pension employment, present giving, food production and ecological security. Especially, in prior development area and eco-functional area, economic contribution is the most important function. Pension employment is the most significant function in main producing areas of agricultural products. In addition, full-time farmer and nonfarm household like pension employment function, while part-time farmer prefer economic function. Besides, Ⅰ-class (land scale ≤0.333 hm2), Ⅱ-class (land scale between 0.333 and 0.667 hm2), and Ⅲ-class (land scale between 0.667 and 1.333 hm2) farmers in prior development areas and Ⅰ-class, Ⅱ-class, Ⅲ-class, and Ⅴ-class (land scale >2 hm2) farmers in eco-functional areas are all concern with the economic function mostly, and Ⅰ-class, Ⅱ-class, and Ⅳ-class (land scale between 1.333 and 2 hm2) farmers in agricultural products producing areas take pension employment as the most significant one, while Ⅱ-class in agricultural products producing areas and Ⅲ-class farmers in eco-functional areas take ecological security function as the most important one. Overall, establishing multifunctional cultivated land management systems and deepening management mechanism are in favor of the conversion of traditional single agricultural mode, which would timely adjust and perfect the economic development goals in main functional areas.
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    Study on Eco-compensation Policy Design for Wetland—A Choice Experiment Approach
    GONG Ya-zhen, HAN Wei, Michael BENNETT, QIU Huan-guang
    2016, 31 (2):  241-251.  doi: 10.11849/zrzyxb.20141538
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    Using Yancheng Rare Bird Nature Reserve as the case study area, this study analyzes farmers' preferences for different attributes to be included in an eco-compensation scheme targeting for wetland protection. Based on detailed field survey data of 288 households, this study empirically analyzes this issue based on the choice experiment approach. The results of this study show that: amount of compensation, years of contract, and right to withdraw from the contract have significant effects on farmers' willingness to participate in the eco-compensation scheme. The results also show that the requirement of land sign-up and pesticide reduction by the eco-compensation scheme can significantly reduce farmers' willingness of being enrolled. By calculating the willingness to accept, we find that right to withdraw and years of contract are the most influential attributes. The study suggests that providing trainings and technical support of pesticide use to local farmers has important implications for nature reserve protection. It also suggests that more flexible compensation scheme can increase the sustainability and efficiency of eco-compensation scheme compared with traditional eco-compensation scheme. All of these findings have been discussed for the design of compensation scheme with regard to the context of current Chinese wetland and nature reserve protection policy.
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    Resource Evaluation
    Research on Land Cover Change in Beijing-Tianjin-Hebei Region during the Last 10 Years Based on Different Geomorphic Units
    ZHAO Min, CHENG Wei-ming, HUANG Kun, WANG Nan, LIU Qiang-yi
    2016, 31 (2):  252-264.  doi: 10.11849/zrzyxb.20141557
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    Provided by State Key Laboratory of Resource and Environmental Information System, which belonged to the Institute of Geographic Science and Natural Resources Research, CAS, land cover data of Beijing-Tianjin-Hebei region in the year of 2000, 2005 and 2010 and 1:1 million digital topography data were used to have a research on land cover change of Beijing-Tianjin-Hebei region in recent 10 years based on different geomorphic units. Variations about the values of leading level, coverage degree and dynamic degree based on different geomorphic units were computed, which would help to have a further discussion about the spatio-temporal differentiation of land cover based on different geomorphic units. The results showed that the major changes of land cover in Beijing-Tianjin-Hebei region in the last ten years were the changes from arable land to the built-up and residential areas, which were dramatic in the geomorphic units of plains, hills and small undulating mountains, while arable land continued shrinking, especially in the geomorphic units of plains, terraces and hills. On the whole, differences about changes of land cover based on different geomorphic units in Beijing-Tianjin-Hebei region in recent 10 years were obvious. To be specific, land cover changes in the geomorphic units of plains, hills and small undulating mountains were dramatic. In the first five years from the year of 2000 to 2010, woodland and meadow had an obvious expansion, especially in the geomorphic units of plains, large undulating mountains and hills, while the expansion of woodland and meadow in the last 5 years from the year of 2000 to 2010 was not obvious. At last the significance of the research of land cover changes in Beijing-Tianjin-Hebei region based on different geomorphic units were discussed, which proved that the research was meaningful, what's more, some recommendations about the research on inherent relationship between geomorphic units and land cover changes were made, which paid more attention to the secondary classification system of both geomorphic units and land cover.
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    Potential Evaluation of Requisition-compensation Balance of Arable Land Production Capacity in the Planning Period Based on Quality Improvement at County Level
    LI Chen, JIN Xiang-mu
    2016, 31 (2):  265-274.  doi: 10.11849/zrzyxb.20150053
    Abstract ( )   HTML ( )   PDF (640KB) ( )   Save
    Due to limited arable land, the conflict between arable land exploitation and ecological land protection is more and more serious. In this context, the requisition-compensation balance of arable land faces significant hurdles. One innovative option to protect arable land is transforming requisition-compensation balance of arable land quantity into requisition-compensation balance of arable land production capacity by improving the quality of arable land. On account of forward-looking consideration of policy and technical reserves, this paper tries to offer a method system for potential evaluation of requisition-compensation balance of arable land production capacity in the planning period based on quality improvement of arable land at county level. The method system built here is based on farmland gradation, general land use planning, and detailed land use survey data, combining with GIS spatial analysis technology. Taking Pingyang County as an example, the applicability of this method system is verified. The study result indicated that: from 2011 to 2020, the production capacity of arable land would lose 19 227.82 t owing to land occupation by construction, and would add 23 104.03 t through arable land consolidation, thus the index number of potential balance of arable land production capacity is 120.16%. Therefore, the method system built in this paper is proved to be well-founded and easy to put into practice,which provides a necessary technological support for formulating and implementing policies on requisition-compensation balance of arable land production capacity.
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    A Study on Limit and Evolutionary Trend of Pollution Effect in Process of Urbanization Based on Marginal Model:An Empirical Study of Anhui Province
    ZHANG Le-qin
    2016, 31 (2):  275-286.  doi: 10.11849/zrzyxb.20150048
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    Exploring the limits of marginal pollution effect of urbanization has important significance in healthy and sustainable development of urbanization. Taking Anhui Province as an example, eight indicators are selected with entropy weight assignment method for evaluating comprehensive pollution indices. LMDI decomposition model is adopted to measure the pollution effect caused by urbanization. Based on the marginal theory in economics, the change rate model of marginal pollution effect caused by urbanization is established. Through the estimation of optimal goodness-of-fit curve and discrimination method of inflection point deri-vation, the limit and evolutionary trend of marginal pollution effect in the process of urbanization are measured. The results show that: 1) the comprehensive pollution index rose from 0.153 0 in 2000 to 0.645 3 in 2012, while the marginal pollution effect caused by urbanization increased from 0.006 3 in 2001 to 0.012 5 in 2012, and both show growing trends; 2) by 2020, the cumulative marginal pollution effect caused by urbanization will reach 0.379; 3) the change rate curve of marginal pollution effect caused by urbanization shows a positive N-shaped, of which the first and the second extreme points appeare in 2004-2005 and 2013 respectively. At present, the marginal pollution effect caused by urbanization is in the rising channel right to the second extreme point. Based on urban development theory, mechanism analysis is conducted on the research results. Meanwhile, four aspects of policy suggestions are proposed, such as relying on scientific and technological innovation to realize the transition of urbanization pattern from factor driving to innovation driving.
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    Research on the Effect of Vegetation and Slope Aspect on the Stability and Erodibility of Soil Aggregate in Loess Hilly Region Based on Le Bissonnais Method
    LI Ya-yun, LIU Lei, AN Shao-shan, ZENG Quan-chao, LI Xin
    2016, 31 (2):  287-298.  doi: 10.11849/zrzyxb.20141207
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    In this article, the distribution characteristics, stability and erodibility of soil aggregate in three zones of forest, forest-steppe and steppe on the Loess Plateau are studied with the Le Bissonnais (LB) method. The effect of vegetation and slope aspect on the characteristics and erodibility of soil aggregate is also discussed. The results show that: 1) for the surface soil (0-20 cm) in different vegetation zones, both the content of soil aggregate (R0.2) and the mean weight diameter (MWD) are less on sunny slopes than on shady slopes, while the soil erodibility factor K is a little bigger on sunny slopes than on shady slopes with no significance. This implies that both the stability and erodibility of soil aggregate are slightly higher on the shady slope than on the sunny slope in the three vegetation zones in hilly loess region, but the differences are not significant. 2) In the surface layer (0-20 cm) under different vegetation, R0.2 and MWD decrease as follows: forest > forest steppe > steppe, while soil erodibility factor K decreases in the following order: steppe> forest-steppe > forest. This suggests that the stability and anti-erosion ability of soil aggregate in the forest vegetation zone is the highest. 3) Under processes of WS (wet-stirring sieving method) and FW (fast-wetting sieving method), there are significant difference between samples in forest zone and in steppe zone in both the soil stability and the soil erodibility (R0.2, MWD, K value), especially under the process of FW. The stability and erodibility of soil in forest-steppe zone are in between. A conclusion can be drawn that in the hilly loess zone, the stability and the anti-erosion ability of soil aggregate is ever increasing from north to south. The stability and the anti-erosion ability of soil aggregate is significantly higher in the southern forest zone than in the northern steppe zone.
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    Study on Phytolith-occluded Organic Carbon and Silicon in a Pleioblastus amarus Forest
    YANG Jie, WU Jia-sen, JIANG Pei-kun, ZHAO Pei-ping
    2016, 31 (2):  299-309.  doi: 10.11849/zrzyxb.20150078
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    Phytolith-occluded organic carbon (PhytOC) can exist in the soil for thousand years, thus it is an important mechanism of long-term carbon sequestration in soils. In this study, Pleioblastus amarus forest in subtropical China was selected as experimental materials to discuss the distribution of silicon, phytolith, and PhytOC in a Pleioblastus amarus forest system. A microwave digestion method was used in this study to isolate phytolith from plant material and soil samples, and the PhytOC were determined by alkali dissolution-spectrophotometry method. The results showed that the contents of phytolith and PhytOC in a Pleioblastus amarus forest system decreased in the order: leaf > branch > culms. For different organs, there was significant linear correlation between Si content and phytolith content (R2 = 0.98, P< 0.01), and between phytolith content and PhytOC content (R2 = 0.52, P< 0.01), and there was significant negative linear correlation between total organic carbon content and PhytOC content (R2 = 0.57, P < 0.01), and between organic carbon content in phytolith and phytolith content (R2 = 0.17, P< 0.01). The PhytOC stocked in branches and culms accounted for 17.2% and 51.1% of total PhytOC stock in above-ground part, respectively. PhytOC stocked in leaves, branches and culms accounted for 0.59%, 0.21% and 0.28% of total organic carbon stock, respectively. The ratios of PhytOC/total organic carbon greatly varied in different organs. The phytolith contents in bamboo plants were linearly correlated with plant-available Si contents in the soil (R2 = 0.91, P< 0.05), but poorly correlated with total Si contents in the soil (R2 = 0.16, P> 0.05). The PhytOC production rate in the Pleioblastus amarus forest system studied was 40.2 kg·hm-2·a-1.
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    Determination of Heavy Metal Baseline in Baotou and Bayan Obo and Its Application in the Assessment of Heavy Metal Contamination
    ZHU Xiao-dong, WEI Chao-yang, YANG Fen
    2016, 31 (2):  310-320.  doi: 10.11849/zrzyxb.20141565
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    Based on the principle of geochemical baseline, the baseline values of six heavy metals, including As, Cr, Cu, Ni, Pb and Zn in Baotou city and Bayan Bbo mining area were determined with reference element method and cumulative frequency curve method. Baseline with reference element method was, at Baotou: 8.85 mg/kg As, 123.15 mg/kg Cr, 24.61 mg/kg Cu, 19.72 mg/kg Ni, 27.39 mg/kg Pb and 74.25 mg/kg Zn; at Bayan Obo: 16.16 mg/kg As, 127.17 mg/kg Cr, 31.07 mg/kg Cu, 28.94 mg/kg Ni, 33.82 mg/kg Pb and 80.52 mg/kg Zn. Baseline with cumulative frequency curve method was, at Baotou : 8.45 mg/kg As, 113.78 mg/kg Cr, 16.12 mg/kg Cu, 16.23 mg/kg Ni, 19.66 mg/kg Pb and 48.59 mg/kg Zn; Bayan Obo: 16.01 mg/kg As, 121.56 mg/kg Cr, 21.85 mg/kg Cu, 29.37 mg/kg Ni, 24.32 mg/kg Pb and 72.89 mg/kg Zn. Generally, the baseline values of Bayan Obo was higher than those in Baotou. The contamination of various heavy metals in Baotou and Bayan Obo were assessed using single-factor contamination index. When the background values of Inner Mongolia were used as the references, the numbers of none, slight, mild and moderate contaminated samples in Bayan Obo were 0.3, 1.0, 1.5 and 1.7 times of those in Baotou, indicating the contamination in Bayan Obo was higher than in Baotou. However, when baseline values were used as the references, the numbers of none, slight, mild and moderate contaminated samples in Bayan Obo were 1.0, 1.1, 0.7 and 0.5 times of those in Baotou. Since both areas had small numbers of moderately contaminated samples, no significant differences between Baotou and Bayan Obo was actually seen at contaminative levels. Assessment of the contamination of heavy metals in these two areas using the baselines reflected reasonable contributions of human activities, whereas using background values of Inner Mongolia gave rise to distorted recognition of such contributions.
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    Comparison on Phosphorus Budgets in Two Typical Subtropical Small Watersheds of China
    WANG Mei-hui, ZHOU Jiao-gen, HAN Zeng, MENG Cen, YANG Wen, JIAO Jun-xia, CHENG Mu-chun, LI Yu-yuan, WU Jin-shui
    2016, 31 (2):  321-330.  doi: 10.11849/zrzyxb.20141612
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    Surplus phosphorus is a main source of non-point source pollution. Tuojia, a small agricultural watershed (52 km2) and Jianshan, a small forest-agricultural watershed (50 km2), located in Changsha County, Hunan Province, are taken as the case study. Based on the household surveys and 4-successive-year of observations of the phosphorus (P) flows at the terminal of river, substance flow analysis was used to quantify the budgets of P. Results showed that the concentrations of P in the agricultural ranged 0.03-0.68 mg·L-1, with the average 0.21 mg·L-1, while the corresponding one in the forest-agricultural ranged 0.01-0.35 mg·L-1 with the average 0.08 mg·L-1. The surface water quality in the forest-agricultural watershed was obviously better than that in the agricultural watershed. The phosphorus surplus intensity in the agricultural watershed was apparently higher (32.0 kg·hm-2·a-1) than that in the forest-agricul-tural watershed (20.6 kg·hm-2·a-1), and thus had a greater effect on environment. In 2013, livestock feeding accounted for 53.1% of total P inputs in the agricultural watershed, while fertilizer contributed 53.0% in the forest-agricultural. Generally, the phosphorus from plant and animal products dominated in both watersheds, approximately accounting for 94.0% of the total. Thus, controlling the amount of P fertilizer and improving its utilization efficiency are good ways to mitigate the eutrophication in the study area.
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    Study on the Sensitivity and Vulnerability of Single Cropping Rice Yield to Climate Change in Sichuan
    CHEN Chao, PANG Yan-mei, ZHANG Yu-fang, MA Zhen-feng
    2016, 31 (2):  331-342.  doi: 10.11849/zrzyxb.20141603
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    Based on the meteorological data and single cropping rice production at 25 meteorological stations spreading over the single cropping rice growing regions of Sichuan Province during 1981-2012, the sensitivity and vulnerability of single cropping rice yield to climatic factors and climate change were estimated by using the regression relationships between single cropping rice yield and related climatic variables. The results showed that the air temperature during the growing season of single cropping rice increased from 1981 to 2012, meanwhile the precipitation and solar radiation showed decreased. With 1 ℃ increase of air temperature, 1 ℃ increase of diurnal temperature range, 100 mm decrease of precipitation and 100 MJ/m2 decrease of radiation, the yield of single cropping rice in many areas declined. The area vulnerable to temperature change is the largest, and that to the change of diurnal temperature range is the second largest. The responses of single cropping rice yield to climatic factors mainly occurred at the stages from heading to maturity and from transplanting to tillering. The single cropping rice yield at all observed stations are sensitive to the combined effects of the six climatic variables, but only 50% areas are vulnerable. About 43% of rice yield variation was caused by climate change in recent 30 years. There were great differences in the responses of single cropping rice yield to the climatic factors at different stations and different growth stages. Therefore, we need to avoid the negative impacts of climate change and make good use of favorable climatic resources during important rice growing periods based on local conditions, in order to ensure the rice production safety in Sichuan Province.
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    Analysis on the Climatic Characteristics of the Precipitation Variations at “Ya'an Sky-leakage”
    ZHOU Qiu-xue, LI Yue-qing, JIANG Xing-wen, ZHANG Jing
    2016, 31 (2):  343-353.  doi: 10.11849/zrzyxb.20141350
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    Based on the daily precipitation data during 1951-2008 and hourly precipitation data during 1969-2000 at Ya'an station, multiple time scale variations of precipitation amount and precipitation frequency at “Ya'an sky-leakage” which locates at the eastern edge of the Tibetan Plateau are investigated. The result of conventional statistical diagnostic method shows that the annual precipitation and annual rain days are reducing during the last 58 years at “Ya'an sky-leakage”, and the decrease of rain days is more obvious than that of precipitation. Particularly, the annual precipitation sharply declined after the 1990s due to the decreased of both rain days and rainfall intensity. Except in winter, the trends of precipitation in other three seasons are all downward. Among all seasons, the reductions of precipitation and rain days in autumn are the most obvious. The precipitation reduction in flood season accounts for 92.7% of the annual precipitation reduction. The decrease of rain days in flood season is more obvious than that of precipitation, which account for 62.9% of the annual rain days' reduction. After the beginning of the 21st century, the strong precipitation months decreased, and the aggregated period of rain days shortened significantly. The night rainfall is the most prominent characteristic at “Ya'an sky-leakage”. Both the amount and frequency of rainfall in the night are much more than in the daytime. There is a peak of the rainfall in the night, and the increase rate from valley to peak is twice as much as the decrease rate from peak to valley, so it is easy to form heavy rain at night, and it is obviously lasting. However, further analysis found that not only the amount and frequency of night rainfall reduced at “Ya'an sky-leakage”, but also the precipitation peak occurred earlier than before.
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    Analysis on Tendency of Middle and Low Air Wind Speed over Yichang Region
    MENG Dan, CHEN Zheng-hong, DING Nai-qian, CHEN Cheng
    2016, 31 (2):  354-362.  doi: 10.11849/zrzyxb.20141631
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    Based on the data of daily radiosonde wind (altitude below 3 000 m) from 1958 to 2013 in Yichang, the tendency variation of middle-low air wind speed over Yichang region are analyzed by using trend coefficient, moving t-test, and wavelet analysis, and the variations of middle and low air wind speed and surface wind speed in the same period are compared. The results show that: 1) Variation of monthly mean wind speed at 500 m and 1 000 m height are bimodal curves, the monthly mean wind speed at 1 500 m and 2 000 m height are more consistent, while the monthly mean wind speed at 3 000 m fluctuate violently. 2) Seen from the seasonal distribution, mean wind speeds at 500 m and 1 000 m height are maximum in spring, while the wind speed at 3 000 m height is the largest in winter; the vertical increased amplitude of wind speed vary at different altitude. 3) The annual and seasonal variations of wind speed at 500 m height are the fiercest; the deviation factor of annual mean wind speed decreases significantly from 500 m to 2 000 m height. 4) From 1971 to 2013, the annual mean wind speed on surface (10 m), and those of at 500 m, 2 000 m, and 3 000 m height all showed significant decreasing trend, while the annual mean wind speeds at 1 000 m and 1 500 m increased a little with no significance. 5) The middle and low air wind speed mainly experienced from decline to rise in the 1980s and from rise to decline in the 1990s; the number of abrupt changes is maximum in winter, and it is minimum in summer; in addition, the number of abrupt changes of annual and seasonal mean wind speed decreased with the increase of height. 6) There are long term cycle of 8-14 a and short term cycle of 2-4 a of annual mean wind speed at each altitude, that the former mainly concerned with summer and autumn, while the latter mainly concerned with spring and winter.
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