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Table of Content

    25 June 2019, Volume 41 Issue 6 Previous Issue    Next Issue
    Orginal Article
    Sharing of watershed ecosystem service value horizontal compensation burden by downstream cities
    Yiqi WANG, Guoping LI, Buqing YAN
    2019, 41 (6):  1013-1023.  doi: 10.18402/resci.2019.06.01
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    Horizontal ecological compensation as an important institutional arrangement for achieving ecological protection and promoting coordinated development between upstream and downstream areas can realize both socioeconomic and environmental benefits in a win-win situation. Based on the principles of welfare economics and environmental economics, this study constructed a theoretical model for horizontal compensation of watershed ecological service value that can maximize social utility. It is found that only when downstream local governments transfer funds to an upstream area in a fair amount can upstream area’s reduction in utility caused by protecting ecosystem services be reasonably compensated for. By combining analytic hierarchy process with structural entropy weight method, we calculated weights of horizontal compensation that should be shared by local governments in a downstream area. Taking the Weihe River watershed as an example, it is estimated that the proportions of the horizontal compensation for the upstream area by Baoji, Xianyang, Xi’an, and Weinan city governments of the Weihe River watershed downstream area are 27.11%, 22.24%, 29.82%, and 20.83%. Thereby, the horizontal compensation share of the downstream local governments that can improve social utility is obtained. In the proposed burden-sharing scheme, the proportion of compensation burden to be borne by Xi’an, Baoji, Xianyang, and Weinan governments decreases successively, in line with the economic development level of the four cities. The assessment results quantitatively determine the responsibility of the local governments of the downstream area, which not only gives consideration to efficiency and fairness, but also helps strengthen the sense of responsibility of the local governments in the downstream area to protect and build the ecological environment of the watershed.

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    Policy optimization of coal production capacity in China based on a computable general equilibrium model
    Ling HE, Qi CUI, Hao CHEN, Tao SONG
    2019, 41 (6):  1024-1034.  doi: 10.18402/resci.2019.06.02
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    Based on CHINAGEM, a MONASH-style dynamic computable general equilibrium (CGE) model, this study constructed China’s energy economic equilibrium model, conducted a differentiated multi-scenario policy analysis, and compared the impacts of different coal productivity policies and their portfolio on China’s macro economy and industries. The results show that, while optimizing coal production structure, the coal productivity policy significantly affects the output of other energy industries and non-energy industries with upstream and downstream linkages, and inevitably has a certain impact on the macro economy. Among the coal production capability policies, reducing non-quality coal production is most effective in optimizing coal production structure, but it has the greatest negative impacts on macro economy. While taxation policy would have a slightly negative impact on macro economy in that national GDP falls by 0.06%, it has the weakest effect in improving coal production structure. The impacts of reducing production capacity fall between the above two policies. In implementing coal production capacity policies, several policies including tax incentives, production capability replacement, and technological advancement would simultaneously improve coal production structure and dampen the negative impacts on macro economy, and ultimately achieve long-term development of the coal industry. It is more reasonable to simulate the capacity policy by means of reducing capital input, which is more in line with the economic meaning of coal deactivation. This method is also applicable to the research of steel, glass, cement, and other industries.

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    Spatial morphology of rural settlements based on site and functional characteristics
    Yanbo QU, Shuwen WEI, Ran SHANG, Jie ZHENG
    2019, 41 (6):  1035-1047.  doi: 10.18402/resci.2019.06.03
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    Adjustment of rural residential land use in the process of urban-rural transformation and development should be based on the systematic understanding and classification of its spatial morphology. Based on the “2+3” sampling method to select five typical townships and 15 villages in different regions of Shandong Province as the research object, this study constructed a conceptual model of rural settlement morphology from the perspective of site and functional characteristics coupling. Rural settlements were divided by scale, shape, and density indicators of the “site” attribute, and system functions of rural settlements were analyzed based on production, living, and ecological indicators of the “functional” attribute. Then the site-function coupling characteristics of rural settlements were revealed through comparative analysis. The study found that: (1) The scale of rural settlements in the surveyed townships is quite different, the density is relatively concentrated, and the shape is irregular; the combination of rural settlement characteristics in economically backward and mountainous areas are relatively simple, and the types of rural settlements in economically developed and plain areas are diverse. (2) With regard to functions, the overall performance of the surveyed rural settlements is good in production function, poor in living function, and average in ecological function. With the attenuation of location advantage in the townships, the production function of the surveyed villages gradually reduces and tends to become average, the living function gradually reduces but the degree of differentiation becomes more severe, and the ecological function also gradually reduces but the reduction is relatively balanced. (3) With regard to site-function coupling, the living and ecological functions of “large scale-agglomerated” rural settlements are high, the “small scale-distributed” rural settlements have slightly stronger living functions, and the functions of “large scale-distributed-regular shaped” rural settlements are relatively weak. The correlation between combination type and functional relationship is a reflection of the self-organization of internal elements of rural settlements under the guidance of external factors.

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    Development types of rural revitalization based on the identification of development elements in China
    Zhen XIE, Fengrong ZHANG, Songlin CHEN, Suqiong WEI, Jia AO, Yang GAO, Fei LUN
    2019, 41 (6):  1048-1058.  doi: 10.18402/resci.2019.06.04
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    Differentiated promotion, targeted measures, and scientific planning are the scientific procedure for implementing the strategy of rural revitalization. Using the cases of 99 model villages of the beautiful countryside program in China, this study built a database of “successful cases” for rural development, and then endogenous and exogenous element-combination information of rural development was extracted. Furthermore, a rural revitalization diagnosis system was constructed to classify the rural areas by the projection pursuit classification method. The results show that: (1) Livelihood resources, industrial base, location and transportation, cultural/ecological environment, and market demand are important basic elements for successful rural development, among which market demand is the exogenous element and the others are endogenous elements for rural development, but the most important element of all is livelihood resources. (2) The potential of rural revitalization is affected by the structure of element combination directly, and 10 types of combinations were identified from the successful cases. The combination of excellent livelihood resources, location and transportation advantages, healthy cultural/ecological environment, and lack of industrial infrastructure is of the highest potential for rural development. (3) Based on the endowment of element-combination, the rural revitalization diagnosis system includes an evaluation system and a classification system, and the rural areas were divided into priority revitalization, preparatory revitalization, preservation, and resettlement types. Rural revitalization in China must take into consideration actual local conditions and implement the program in an orderly and differentiated manner, avoiding the mistakes of focusing only on individual villages or revitalizing every village.

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    Impact of short-term government intervention on the periodic fluctuation of residential land price
    Yaoyao LI, Daolin ZHU, Jiangmeng ZHAO, Ting DU
    2019, 41 (6):  1059-1069.  doi: 10.18402/resci.2019.06.05
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    In order to explore the effect of short-term government intervention on the periodic fluctuation of land price, this study put forward that the government takes on dual roles when it makes policy to adjust and control the land market. Meanwhile, change of the macroeconomic environment and behavior of the “economic man” would lead to the short-term volatility of policy, thus aggravating information asymmetry, affecting the expectation of market subjects and increasing land price fluctuations. Based on the empirical estimates and using k-means clustering method, 31 cities in China were divided into four categories according to the characteristics of fluctuation of residential land price. The study selected Beijing and Shanghai, among the 31 cities, for regression analysis between the periodic fluctuation of residential land price and short-term policy intervention. The study found that although the fluctuation of residential land price in all cities showed an asymmetric structure of “sharp rise and slow fall”, the impact of government short-term intervention behavior on the fluctuation of residential land price had obvious differences among these cities. The fluctuation of residential land price in Beijing was not significantly affected by the short-term intervention of the government, while there was a significant positive correlation between the short-term intervention by means of macroeconomic policies of the government and the fluctuation of residential land price in Shanghai. In addition, different policies showed different impact intensities. The change of fiscal policies had the greatest effect on the fluctuation of residential land price, followed by monetary policy and land policy.

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    Effects of cultivated land transition on ecosystem service value in Shaanxi Province of China
    Zhenmin DING, Shunbo YAO
    2019, 41 (6):  1070-1081.  doi: 10.18402/resci.2019.06.06
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    This study developed a panel threshold model to examine the impact of cultivated land transition due to urban expansion and ecological restoration project on ecosystem service value, according to the economic analysis framework based on land use/land cover change derived from remote sensing data of 1990-2015 in Shaanxi Province. Cultivated land transition has moved in two opposite directions driven by urban expansion and ecological restoration policy. Urban expansion affects negatively and significantly on ecosystem service value, but its marginal effect is a function of the rate of forest and grassland coverage. With the implementation of the Grain for Green project, forest and grassland coverage increase can make up for the loss of the ecosystem service value caused by urban expansion. The rate of forest and grassland coverage is captured by the panel threshold model, which indicates that when this rate reaches 87.3%, urban expansion has no significant impact on the ecosystem service value. In 2017, the rate of forest and grassland coverage in Shaanxi Province was 68.83%. Therefore it is essential for the province to further expand the scale of returning farmland to forest (grass) to ensure regional ecological security and meet the needs of ecological civilization construction while ensuring that the basic farmlands remain unchanged.

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    Worst case scenario-based methodology for simulating land-use change in coastal city in China: A case study of Lianyungang
    Xiaoyan YANG, Yu LING, Long LI, Longgao CHEN, Longqian CHEN
    2019, 41 (6):  1082-1092.  doi: 10.18402/resci.2019.06.07
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    Simulating and predicting future land-use pattern is of great importance for supporting land-use eco-environmental impact assessment and optimizing land-use planning schemes. Using artificial neural network (ANN) and cellular automata (CA) based future land use simulation (FLUS) model, we proposed a land-use change simulation methodology and applied it for predicting the land-use pattern in a coastal city of China, Lianyungang, in 2020 using the worst case scenario-based (WSB) constraint and non-worst case scenario-based (NWSB) models. The results indicate that: (1) The “worst case” areas are mainly identified in the central-eastern part of the city with a national nature reserve, high elevation and steep slope, natural forests, and water bodies such as rivers, lakes, and reservoirs, and the area is 489.67 km2; (2) With or without the constraint of prohibiting factors or “worst case”, urban land would both expand to a large extent; and with the WSB constraint urban expansion would avoid the “worst case” areas; (3) More arable land would convert into rural residential land in the simulation based on NWSB than with WSB constraint, indicating that the land use simulation with WSB constraint can decrease the occupation of arable land when additional rural residential land is needed; However, (4) the overall area of arable land converting to urban land is lager in the simulation based on the WSB constraint due to the restriction of land use conversion in the “worst case” areas, which challenges the arable land protection strategy in the city. The simulation and prediction of future land-use pattern based on the “worst case” constraint can support eco-environmental protection and regional sustainable development as well as local land-use planning and management. It may also provide a reference for land-use change simulation in other areas.

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    Spatial distribution and temporal changes of facility agriculture on the Tibetan Plateau
    Hui WEI, Changhe LV, Yaqun LIU, Kaijie YANG
    2019, 41 (6):  1093-1101.  doi: 10.18402/resci.2019.06.08
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    During the past decade, the rapid growth of facility agriculture has been a new highlight of agricultural development in the Tibetan Plateau. Revealing the spatial distribution and change characteristics of facility agriculture is helpful for understanding its development trend and can provide supports for its planning and spatial layout on the plateau. Based on the high-resolution imagery data of Google Earth in 2018, this study obtained and revealed the spatial distribution of facility agriculture on the plateau by visual interpretation combined with geostatistical analysis. Further, the spatiotemporal changes of facility agriculture in Xining and Lhasa Cities were analyzed based on high-resolution images of 2008 and 2018. The results show that: (1) In 2018, the total area of facility agriculture on the Tibetan Plateau was 7821.74 hm2, mainly distributed at the periphery of cities in river basins, roughly in line with the rivers. Of the total facility agriculture lands, 58.10% was distributed in Qinghai Province and 36.49% in Tibet Autonomous Region; (2) Facility agriculture showed a significant altitudinal differentiation under the influence of topographic factors. The land was distributed between 1400 m and 4600 m, mostly concentrated in two elevation zones of 2200~2600 m and 3600~3700 m; (3) Facility agriculture grew rapidly in Xining and Lhasa Cities from 2008 to 2018, with the area increased from 293.73 hm2 and 429.01 hm2 to 2111.45 hm2 and 1422.30 hm2, respectively. At the same time, more than 60% of facility agriculture lands in the urban areas was occupied by built-up land, resulting in significant changes in the spatial pattern; (4) There is a good prospect for the development of facility agriculture in the region because of strongly anticipated growing demands for vegetables and melons driven by the rapid urbanization and tourism development. To that end, a general planning for facility agricultural development is needed in order to avoid the lands being frequently changed and resulting in wasteful use, improve the situation of highly depending on single type of greenhouses, and avoid possible ecological problems such as plastic pollution.

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    Relationships between cultivated land quality and land transfer behaviors at the plot scale
    Yali ZHANG, Yunli BAI, Liangjie XIN
    2019, 41 (6):  1102-1110.  doi: 10.18402/resci.2019.06.09
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    Low land transfer restricts the scale and modernization of agriculture. Based on a sample of 312 households and 1527 plots of 12 typical administrative villages in Heilongjiang and Jilin provinces in 2017, this study used the ordinary least squares (OLS) and Probit models to explore the impact of cultivated land quality on land transfer behaviors at the scale of plots. The results indicate that: (1) Cultivated land quality has a significant impact on whether a plot is rent out or rent in. Plots with large area, flat slopes, and well-irrigated condition have a higher probability of being rent in, while plots that are small in size and far away from homes have a relatively lower probability of being rent out. (2) Non-agricultural income has a positive effect on rent out behavior of farmer. (3) The older the head of the household, the higher the probability that the farmer will participate in the land transfer. The farmers with lower education have a higher probability of renting in plots. The greater the number of agricultural fixed assets, the more reluctant the farmers are to rent out plots. There is less possibility of renting in plots for the family who has the larger contracted farmland. Some policy implications can be drawn from the results. The direction of related policy is to attract new agricultural management organizations to rent in farmland, and thus to promote land transfer market and to improve land quality. Simultaneously, improving the level of agricultural mechanization and agricultural production efficiency with higher land transfer levels need to be further valued.

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    Analysis on residents’ behavior of domestic solid waste source separation based on structural equation
    Xiaoyan MENG
    2019, 41 (6):  1111-1119.  doi: 10.18402/resci.2019.06.10
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    The resident is one of the key subjects in the municipal solid waste separation and recovery system. Residents’ participation in source separation of domestic solid waste is one of the most important factors affecting the success or failure of the urban solid waste seperation work. In this study, in order to analyze the mechanisms of residents’ waste seperation and recovery behaviors, Suzhou City was chosen as a case, a field questionnaire survey of the residents in its central area was conducted, and the key factors affecting residents’ waste sorting and recovery behaviors and their paths were explored using the statistical analysis method of structural equation modeling (SEM). The research results show that the domestic solid waste source separation behaviors of the surveyed residents are closely related to four subjective factors and seven objective factors, and the latter’s comprehensive effect is almost twice that of the former. Among all the factors, the latent variable “environmental facilities and services” has the greatest combined impact, while “public education”, “convenience of recycling facilities”, “convenience of separation facilities”, “willingness to participate”, and “environmental awareness” are the top five factors that affect residents’ domestic solid waste separation behaviors. In order to further accelerate the source separation of domestic solid waste in China, it is recommended to strengthen the planning and construction of municipal solid waste separation and recycling facilities, extensively carry out publicity and education on domestic solid waste separation and recycling, improve relevant laws and regulations, and establish an effective incentive and restraint mechanism.

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    Influencing factors of farmers’ organic fertilizer application behavior and their stratification based on Logistic-ISM model
    Naijuan HU, Xiaoling SUN, Yating XU, Ziyang ZHOU, Liqun ZHU
    2019, 41 (6):  1120-1130.  doi: 10.18402/resci.2019.06.11
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    Organic fertilizer application is beneficial for agricultural green development. However, the rate of application in agricultural production is still very low, especially for rice and wheat production. As rice and wheat are the main crops of agricultural production, it is significance to study farmers’ behavior of organic fertilizer application and the key influencing factors for promoting the application of organic fertilizer in rice and wheat croplands. This study was conducted based on a questionnaire survey of 392 farmers from rice-wheat rotation cropland of Jiangsu Province. We analyzed the influencing factors and their relationships by using a Logistic model and interpretive structural modeling (ISM). The results show that there were eight main influencing factors. Higher educational level, understanding of organic fertilizer, understanding of environmental pollution caused by excessive chemical fertilizer application, consideration of damage to soil when purchasing fertilizer, raising poultry, and guidance of agricultural technology department of the government had positive effects on farmers' organic fertilizer application while higher sensitivity to price of fertilizer and labor saving had a negative effect on organic fertilizer application. By an in-depth analysis, the influencing factors formed a “one path, three driving factors” structure. Based on these results, several suggestions were put forward to promote the application of organic fertilizer.

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    Spatial interpolation of mean temperature of Chongqing Municipality considering solar radiation correction
    Zhiming HE, Yuechen LI, Xianfeng JIN, Xian LIU, Xiaobo HE
    2019, 41 (6):  1131-1140.  doi: 10.18402/resci.2019.06.12
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    The mountainous regions of Southwest China, where Chongqing Municipality is located, has typical regional environmental characteristics such as cloudy fog and less sunshine. In order to realize the spatial simulation of temperature in this geographical environment, this study proposes a model for local regression considering terrain correction factor for solar radiation. In this model, the terrain correction factor is derived indirectly by fitting the spatial distribution of global solar radiation under undulating terrain. The model combines the Geographically Weighted Regression model, the Solar Analyst model, the improved Angtrom-Prescott equation, and the multiple linear regression method. Based on temperature, relative humidity, sunshine percentage, and global solar radiation of the meteorological stations, combined with DEM data with a resolution of 100 m×100 m, this model realizes the spatial simulation of temperature under the mountainous terrain. The model has good fitting accuracy and stability. The simulation accuracy of local regression term is much higher than Inverse Distance Weighting (IDW) interpolation and Kriging interpolation. It is also better than the traditional Multivariate Llinear Regression model based on latitude, longitude, altitude, sunshine percentage, and relative humidity. Further, 55 regional meteorological stations are used to verify the summer temperature simulation accuracy of a single year. The average absolute error is 0.59°C, and the errors of 38 meteorological stations are reduced after considering the terrain correction factor. The model performs well in spatial and temporal simulation of air temperature, which can reflect the influence of local terrain factors such as slope, aspect, and topographic occlusion on temperature, and has clear physical meaning. Based on the available observation data of meteorological stations, DEM, and the commercial software ArcGIS, this model is convenient to apply, especially suitable for cloudy, sunless areas like Chongqing and its surrounding mountainous regions.

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    Evaluation of air temperature of the typical river basin in desert area of Northwest China by the CMIP5 models:A case of the Kaidu-Kongqi River Basin
    Xiaofei LI, Changchun XU, Lu LI, Yingxue LUO, Qiuping YANG, Yuanyuan YANG
    2019, 41 (6):  1141-1153.  doi: 10.18402/resci.2019.06.13
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    Global warming will result in serve water shortage, aggravating the existing outstanding water problem in the Kaidu-Kongqi River Basin. Studies on the future climate change will contribute to the rational distribution and utilization of water in the basin. Based on the CRU(Climate Research Unit) dataset and 32 BCSD-downscaled CMIP5 model air temperature dataset from DCHP (Downscaled CMIP3 and CMIP5 Climate and Hydrology Projections), the paper assessed the simulation ability of both 32 models and multi-model ensemble mean through the test of long-term trend and abrupt change of annual average, maximum and minimum air temperature in the Kaidu-Kongqi River Basin over the period of 1950-2005 by using the methods of linear trend calculation, moving average, Mann-Kendall (M-K) test and moving T-test (MMT). Results show that (1) 12 of 32 models are capable of reproducing the significant warming trend of three temperature indicators during 1950-2005, 8 of 32 models can only simulate that of some temperature indicators, but all of them underestimate the warming rate, so does the multi-model ensemble mean. (2) Most models failed to simulate the time of abrupt change accurately except two, FIO-ESM and MPI-ESM-MR. The ensemble mean of preferred models, PM-PLS and PM-EE, are superior to the individual model in simulating abrupt change. Between them, PM-PLS is better. (3) The further evaluation indicates that the multi-model ensemble PM-PLS can better capture the linear trend of spatio-temporal characteristics, but the problem of underestimating the warming rate still exists. It appeals to strengthen the study of model optimum selection and multiple models assemble in the future climate prediction using climate models.

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    Spatial pattern of urban heat island and multivariate modeling of impact factors in the Guangdong-Hong Kong-Macao Greater Bay area
    Zhiwei YANG, Yingbiao CHEN, Zhifeng WU, Zihao ZHENG, Juanjuan LI
    2019, 41 (6):  1154-1166.  doi: 10.18402/resci.2019.06.14
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    To explore the influence of various factors on the spatial differentiation of urban heat island intensity, and to reveal the impact mechanism of the factors, spatial expression, spatial overlay, and geographical detector methods were used in this study. The impact of five influencing factors on the spatial differentiation of urban heat island intensity in the study area was examined, and a multivariate relationship model was constructed. The results show that the intensity of urban heat island in the Guangdong-Hong Kong-Macao Greater Bay area is high in the central part and low in the surroundings, which has formed a semicircular urban heat island belt on both sides of the estuary of the Pearl River. According to the results of the geographical detector analysis, the five selected factors have a high explanatory power on the spatial differentiation of the urban heat island intensity at the 1 km×1 km grid scale, in the order of population density (0.668) > proportion of construction land area (0.577) > length of roads (0.573) > proportion of vegetation cover (0.538) > proportion of surface water area (0.428). The constructed multivariate relationship model can accurately reflect the distribution of land surface temperature in urban heat island area, and the error between the modeling result and the observed average land surface temperature is 0.34℃.

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    Sea ice distribution and influencing factors in the Yellow Sea and the Bohai Sea during winter 2018
    Cheng LIU, Dasheng CHE, Xiaodong LI
    2019, 41 (6):  1167-1175.  doi: 10.18402/resci.2019.06.15
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    Sea ice is a marine hazard in the Yellow Sea and the Bohai Sea in winters. To reveal the spatial distribution and diurnal change characteristics of sea ice and improve the ability of sea ice short-term forecasting, the National Snow and Ice Data Center (NSIDC) Multisensor Analyzed Sea Ice Extent (MASIE) daily sea ice extent and the European Centre for medium-range weather forecasts (ECMWF) ERA-Interim data were used in this study for analysis. The spatial distribution characteristics of sea ice in the Yellow Sea and the Bohai Sea in 2018 and the relationship between sea ice extent and meteorological factors were examined. The results show that the sea ice was concentrated in the Liaodong Bay and the Korea Bay north of 39°N. With the increase of distance from the coast, its coverage reduced distinctly. Sea ice changes underwent three stages development, stagnation, and melting, and the development stage was longer than the melting stage. Sea surface temperature (SST), air temperature at 2 m height (T2m), and accumulated temperature (while air temperature at 2 m height was colder than -2℃) north of 39°N showed a significant negative correlation with sea ice extent, and the Pearson correlation coefficients were -0.61 (P < 0.01), -0.52 (P < 0.01), and -0.50 (P < 0.01), respectively. In addition, two abnormal decreasing processes of sea ice extent were found in the development stage over the Yellow Sea and the Bohai Sea, and both were mainly caused by the southerly wind and warming of the previous day.

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    Spatiotemporal variation and potential of heat use efficiency of wheat-maize rotation system in Henan Province
    Qing CHANG, Jing WANG, Weidong YU, Ning ZHANG, Mengwei LI, Wenke LI, Mingxia HUANG
    2019, 41 (6):  1176-1187.  doi: 10.18402/resci.2019.06.16
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    To explore the spatial and temporal changes of heat use efficiency (HUE) of wheat, maize, and wheat-maize rotation system and put forward effective measures for fully utilizing regional heat potential and improving HUE based on local production condition in Henan Province, the spatial and temporal characteristics of heat resources and HUE of wheat, maize, and wheat-maize rotation system were examined based on crop yield from the agro-meteorological observational sites and temperature data from meteorological stations respectively from 1981 to 2014 at 17 study sites in the province. The regional differences and the controlling factors of HUE were further revealed based on the statistical analysis results. The study showed that there were large spatial differences in calculated potential effective thermal time, actual effective thermal time, and heat use efficiency of wheat, maize, and wheat-maize rotation system. In 1981 to 2014, the length of growing period of wheat-maize rotation system increased slightly in Northern Henan while decreased in Western Henan. For Eastern and Southern Henan, the length of growing period of wheat-maize rotation system showed a trend of increase-decrease-increase and increased firstly and then decreased, respectively. With the selection of mid-late maturing varieties to adapt to climate change and improve HUE, growing period effective thermal time of wheat and maize increased in all the regions in Henan Province. The gap between potential and actual effective thermal times of wheat and maize increased from the north to the south and from the west to the east in the province. The gap between potential and actual effective thermal times increased for wheat but decreased for maize, which suggests that maize had higher heat use degree than wheat. Under the interactive impacts of crop yield and actual effective thermal time, heat use efficiency of wheat, maize, and wheat-maize rotation system was higher in the north and east of Henan than in the south and west of the province. From 1981 to 2014, potential and actual effective thermal times and heat use efficiency showed increasing trends with different increase rates caused by changes in growing period temperature, the length of crop growth period, and crop yield. In the future, there is an urgent need to improve the utilization of heat use efficiency especially in the Southern and Eastern Henan.

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