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    20 April 2014, Volume 35 Issue 02
    论文
    Distribution and Variation of China Agricultural Heat Resources in 1961-2010
    HU Qi,PAN Xuebiao,SHAO Changxiu,ZHANG Dan,WANG Xiaoxiao,WEI Xiaoyu
    2014, 35(02):  119-127.  doi:10.3969/j.issn.1000-6362.2014.02.001
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    Based on observed meteorological data from 508 stations in China,the distribution characteristics of heat resources were analyzed by using climatic trend rate and GIS methods in national scale in recent 50 years (1961-2010),and the change characteristics of heat resources between two periods (period Ι 1961-1980,period Ⅱ 1981-2010) were compared The results showed that the heat resources distributed unevenly,and more heat resources in southern China than that in northern China The key influence factor in eastern China was latitude,while topography was key factor in western China Counter lines of average daily temperature 0℃,10℃ and 15℃ in period Ⅱ moved northward comparing with period Ι,days of average daily temperature≥0℃ and ≥10℃ increased 5.5d and 4.7d on average,respectively The distribution and change of average daily temperature≥0℃ was similar to that of accumulated temperature≥10℃The areas of the accumulated temperature zone of 5500-6100℃·d (≥0℃accumulated temperature) and 5300-6500℃·d (≥10℃ accumulated temperature) increased by 5.32×10.4km and 1.92×10.3km,respectively The climatic trend rate of average temperature was 0.27℃/10y in 1961-2010,and the climatic trend rate of maximum and minimum temperature was 0.37℃/10y and 0.21℃/10y in northern China The accumulated temperature≥0℃ and ≥10℃increased 70℃d/10y The heat resources (mean temperature,minimum and maximum temperature,accumulated temperature) in China showed a increasing tendency in recent 50 years,and minimum temperature played a major role on climate warming,whose variation degree was larger than that of maximum temperature Climate warming might have some impacts on agricultural production and agro climatic zone (including introduction,maturity type shift and planting area expansion,etc) The research result was helpful to determine the appropriate agro climatic indexes and crop cultivation area
    Study on Above 10℃ Thermal Resources Projected Under Climate Scenario in 21stCentury in Guizhou Province
    MA Jianyong,GU Xiaoping,LIAO Liufeng
    2014, 35(02):  128-134.  doi:10.3969/j.issn.1000-6362.2014.02.002
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    The daily mean temperature from regional climate model system PRECIS (Providing Regional Climate for Impacts Studies) under SRES A1B scenario was calculated to project the tendency of agricultural thermal resources in Guizhou province during 2011-2100The results showed that under A1B scenario,the beginning date steadily above 10℃ would advance significantly,while the ending date might delay also obviously,and an evident increment would be performed both in the lasting days and accumulated temperature Meanwhile,the increasing trend of agricultural thermal resources in the east might be higher than in the west during 2011-2100Compared with baseline,in next 90 years,the biggest advancement of beginning date steadily above 10℃ might be showed in Bijie,Liupanshui and southwest Guizhou region (16-18d),and the ending date of most areas would delay 14-19d,in terms of lasting days,the increment of 31-38d and 23-30d might be represented in the west and east,respectively Accumulated temperature in Guizhou province would also be expected to elevate 878-1162℃·d As far as contour change be concerned,4000℃·d  contour might move eastward from Renhuai-Kaiyang-Longli-Puding-Jin′an-Xingyi line in baseline to high altitude region as Weining,Hezhang in 2080s period,while 6000℃·d contour would be expected to gradually advance to the central Guizhou from northern and southern directions,in 2080s period,the northern contour might shift to Renhuai-Zunyi -Fenggang-Yanhe line,and southern contour might move to An′long-Liuzhi-Huishui-Weng′an-Leishan-Sansui  Tongren line
    Response of Typical Woody Plants Phenology to Climate Warming in Southwestern Shandong Province
    LI Ruiying,SUN Dongbao,JIANG Xiaodong
    2014, 35(02):  135-140.  doi:10.3969/j.issn.1000-6362.2014.02.003
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    The response of 9 woody plants phenology to climate warming was analyzed by using statistical analysis method in southwestern Shandong province The results showed that the temperature had increasing tendency,especially in winter;the increasing tendency of average minimum temperature was higher than average temperature and average maximum temperature in spring,autumn,winter and annual The spring phenology advanced,and autumn phenology delayed The whole phenology of Salix matsudana and the spring phenology of Populus tomentosa and Ulmus pumila advanced significantly (P<0.01),the leaf falling of Ulmus pumila and full leaf color changing and the end of leaf falling of Firmiana simplex delayed significantly (P<0.01)There was negative correlation between the spring phenology and average temperature during former 1-2 months and annual temperature,and positive correlation between the autumn phenology and average minimum temperature of former 1-2 tenday of former month Salix matsudana was the most sensitive to climate warming in 9 woody plants,followed by Populus tomentosa and Ulmus pumila,Albizzia julibrissin and Firmiana simplex were the most insensitive The research results could provide reference for urban greening and farming season prediction
    Study on the Pathway and Dynamics of N2O Emissions From the Vegetable Soil Fertilized With Ammonium Nitrogen
    YAN Hongliang,ZHANG Xuan,XIE Liyong,HE Cuicui,REN Huanyu,ZHANG He,FAN Jingwei,LIN Miao ,GUO Liping
    2014, 35(02):  141-148.  doi:10.3969/j.issn.1000-6362.2014.02.004
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    Nitrous oxide is one of the most important greenhouse gases emitted from fertilized agricultural soils.Vegetable soil may contribute great share to the national N2O emissions due to the higher fertilization rate,multiple application and irrigation This experiment aimed to investigate the contributions of various N2O production processes after ammonium nitrogen was applied during three weeks laboratory incubation period under 70% field water capacity in a vegetable soil We used the different gas inhibitors to distinguish the different N2O production processes The treatments include no gas inhibitor (CK),0.06% acetylene (A),pure oxygen (O),0.06% acetylene plus pure oxygen (AO),pure helium(H)Based on the processes occurred or inhibited under different gas inhibitor treatments,N2O fluxes and its contribution and dynamics from autotrophic nitrification,nitrifier denitrofication and denitrification were calculated and analyzed during the incubation periodThe results showed that N2O fluxes were peaked at 314.4ngg-1d-1within the 48h after fertilization,and then rapidly decreased to 1/6 of that by the 4th day followed by more decreased quantity with the increase of incubation time Autotrophic nitrification contributing more than 50% and 40% of total N2O fluxes within two weeks and thereafter respectively,was the main source of N2O emissions after ammonium nitrogen was applied. Nitrifier denitrification contributed greatly (up to 44%) to the total N2O emission fluxes within 2days after fertilization and about 14%-27% thereafter Although the contribution of denitrification on total N2O emission fluxes were increased from 1%within the first 2 days period to about 30% after two weeks later with the decrease of soil ammonium and increase of soil nitrate,its substantial contribution on N2O fluxes were still less due to the lower absolute N2O flux quantities (about 1/20 of that within the first 2 days) two weeks later N2O production and its sources were associated with the content and dynamics of soil ammonium and nitrate Soil pH showed decrease after ammonium nitrogen application. Therefore,control the speed of nitrification is a better option to decrease the N2O emissions in the vegetable soils fertilized with ammonium nitrogen
    Influence of Solid Concentration on Methane Output of Anaerobic Digestion ofSwine Manure
    CHEN Xin,TU Deyu,SUI Qianwen,LIU Chong,DONG Hongmin
    2014, 35(02):  149-155.  doi:10.3969/j.issn.1000-6362.2014.02.005
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    Lab-scale experiments were conducted using the Automatic Methane Potential Test System (AMPTS) under the condition of 35℃ to investigate the influence of swine manure total solid (TS) concentrations of 2%,6%,10% and 14% on the anaerobic digestion and methane production The results showed that biogas output from all treatments were maximum in the first day,and gradually declined with the digestion days The higher solid concentration required longer digestion time The larger methane concentration of biogas was obtained from low TS treatment in the beginning period However,methane concentration from high TS treatment gradually increased as the extension of digestion time Methane concentrations of biogas from TS of 6% treatment were highest in the later periods of experiment,and could reach 76.1% In the range of TS of 2%-10%,the larger cumulative methane production was obtained from the higher concentration,other than the cumulative methane production from TS of 14% which was no significant differences compared with that from TS of 10%To calculate the methane yield per CODcr from different treatments of TS of 2%,6%,10%,and 14%,was 311.5 409.7,488.8,and 357.4mL/g,respectively,and the methane yield per VS from different treatments of TS of 2%,6%,10%,and 14%,was 330.1 ,491.3,473.1,and 491.3mL/g,respectively The larger methane yield was obtained from TS of 6% and 10%Research results showed that solid concentration of swine manure had a great influence on anaerobic digestion process and the methane yield Selecting suitable solid concentration was beneficial to improve the methane production of anaerobic digestion The experiment results provide useful reference data for the selection of biogas digesters design parameters and support the compilation of GHG inventory from manure management
    Effects of Biochar on Soil Nutrients and Nitrogen Leaching in Anthropogenic Alluvial Soil
    HUI Jinzhuo,ZHAGN Aiping,LIU Ruliang,WANG Yongsheng,CHEN Zhe,YANG Zhengli
    2014, 35(02):  156-161.  doi:10.3969/j.issn.1000-6362.2014.02.006
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    Anthropogenic alluvial soil was the main species in Ningxia irrigation district The crude farming methods are used in the paddy planting,such as uncontrolled irrigation and excessive fertilization,leading to a high leaching of nitrate nitrogen to the surface water Soil column leaching method was used to study the effect of different amount of biochar application on nitrogen leaching and soil nutrient availability in anthropogenic alluvial soil The results showed that there was no significant difference in soil pH,the content of total salt and phosphorus between the biochar addition treatments and control but,the content of total soil nitrogen,available phosphorus,available kalium was significantly increased with the biochar application amount Applying biochar significantly reduced the concentration and leaching amount of nitrate nitrogen2% biochar addition reduced the nitrate nitrogen leaching by 49% when compared with the control The leaching peak of ammonium nitrogen was delayed with the increase of biochar addition. The significant decrease of ammonium nitrogen leaching (18%) was found only in the treatment of 10% biochar addition. However,the opposite trend was found in the other biochar addition,compared with the control Whether the species of biochar affect nitrogen leaching in anthropogenic alluvial soil needs to be further studied
    Effect of Seed Soaking With Salicylic Acid and α-Naphthaleneacetic Acid on Drought Resistance of Winter Wheat
    TANG Xiaochuan,ZHANG Yuancheng,ZHONG Xiuli,BAI Wenbo,LV Guohua,SONG Jiqing
    2014, 35(02):  162-167.  doi:10.3969/j.issn.1000-6362.2014.02.007
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    Effect of SA and NAA on the winter wheat(Aikang58) seedling were studied by comparing the growth and physiological characteristics of seedling in different treatment There were four treatments,namely soaked in distilled water(CK),salicylic acid(SA),α-naphthaleneacetic acid (NAA) and the mixture of salicylic acid and α-naphthaleneacetic acid (SA+NAA)The experiment was conducted in the petri dish Seeds of the contrast check were always cultured in distilled water while others were firstly cultured in distilled water for 5 days to accomplish germination and accumulate certain biomass and then in PEG solution (15%) for 4 days to simulate drought stress The results showed that under distilled water condition,SA (0.5mmol/L) could enhance seedling growth rate and NAA (20mg/kg) could increase root/shoot ratio of the wheat seedling SA+NAA showed advantages as a mixture Under osmotic stress condition,NAA and SA+NAA could increase the biomass of the wheat seedling,SA and SA+NAA could improve plant water status and decrease the electrolyte leakage.As seed soaking agent,SA and NAA could increase root/shoot ratio and the biomass of wheat seeding,alleviate the damage of osmotic stress and enhance the drought resistance of wheat seedlings. The effect of SA+NAA was better than SA or NAA separately
    Measurement and Heat Flux Analysis on North Earthen Wall in Chinese Solar Greenhouse
    PENG Dongling,YANG Qichang,WEI Lingling,ZHANG Yi,FANG Hui
    2014, 35(02):  168-173.  doi:10.3969/j.issn.1000-6362.2014.02.008
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    To investigate the heat transfer characteristics of north earthen wall of Chinese solar greenhouses,a study was conducted in a Chinese solar greenhouse which was located in Shouguang city,Shangdong province The temperatures of different layers in the north wall,solar irradiance on the surface of north wall,indoor and outdoor air temperatures were continuously monitored The results showed that the temperatures of different layers of north wall presented certain daily variation The heat fluxes of the north wall followed the same patterns was the wall temperatures Heat conduction occurred mainly at the surface layer due to its obvious heat storage and release during the day and night,respectively. On a sunny day,the total heat stored by the wall during the daytime and released to the greenhouse during night were 2657 and 1865kJm-2,respectively On a snowy day,the total heat stored and released were 18 and 859kJm-2,respectively. Experimental results also showed that there were heat storage and insulation layers in the north wall of Chinese solar greenhouses and the functions of two layers were different It is suggested that using different materials for the heat storage and insulation layers of north wall could achieve better performance than homogeneous walls
    Heat Preservation Experimental Study on Phase Change Wall Materials for Sinking Solar Greenhouse in Zhengzhou
    LIU Xiaoyu,HE Cui,DU Liang,HOU Weina,LIU Xu,SUN Zhiqiang
    2014, 35(02):  174-179.  doi:10.3969/j.issn.1000-6362.2014.02.009
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    Taking the hydrated inorganic composite phase-change materials (FCPCM),mainly CaCl2,as basis filler in interlayer of back wall of sinking solar greenhouse in Zhengzhou .The variation of indoor temperature,the surface of back wall temperature and outdoor temperature in typical weather conditions between CPCM greenhouse and CK was observed and discussed.The results showed that the average rising rate of CPCM greenhouse was 3.26℃/h uncovering the insulation cloth in sunny days,which was lower than CK(CK is 3.65℃/h).The highest temperature of CPCM greenhouse was slightly lower than CK in the afternoon.The surface temperature of the back wall was 3.9℃ higher than that of CK during daytime,and 1.8℃ higher than that of CK at night .The range of temperature between indoor and outdoor was higher than that of CK The interior temperature and the surface temperature of back wall interlayer and the variation of temperature between indoor and outdoor changed similar in rainy days .The interior temperature and the surface temperature of back wall decreased at the rate of 0.08℃/h in CPCM greenhouse,which was higher than that of CK The range of temperature between indoor and outdoor was little,while it increased gradually in CK Heat could be absorbed and stored by FCPCM effectively to increase the temperature of greenhouse,which was good for growing The results could provide theoric basic for understanding the properties of hydrated salt composite phase change material
    Analysis on Precipitation Distribution During Main Growth Period and Its Effect on Spring Potato in Western Guizhou
    CHI Zai xiang, XIAO Jun, GONG Xue qin, DU Zheng jing, WU Hua hong,YU Fei
    2014, 35(02):  180-186.  doi:10.3969/j.issn.1000-6362.2014.02.010
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    Based on observed daily precipitation data during whole growth period of spring potato(from sowing to harvest)from 2006 to 2011 and average yield data of Weiyu 3 at 4 test spots with different altitude in Liuzhi,Zhongshan,Shuicheng and Pan county in western Guizhou,the precipitation change and its effect on spring potato yield was analyzed by using precipitation yield integral regression method.The results showed that the spatial and temporal distribution of precipitation in western Guizhou was inhomogeneous,but the precipitation increased with the altitude rising.The main reason to unstable yield of spring potato was uneven distribution of precipitation in different growth stages and less precipitation in whole growth period(less than 600mm).The optimal irrigation time during whole spring potato growth period was different in different regions.Irrigation was needed at emergence stage,branching stage and squaring stage in eastern Guizhou,irrigation was needed at seeding time,emergence stage,squaring stage and flowering stage in northern Guizhou.Supplementary irrigation was needed at flowering stage in northern Guizhou,and supplementary irrigation was needed at full blooming stage in center of Guizhou.The research result was helpful to determine the optional irrigation time of spring potato,optimize the production patterns and increase spring potato yield.
    Application of Newly Developed Cluster Analysis of Statistical Test in Fine Agro Meteorological Yield Prediction
    QIU Mei juan,SONG Ying bo,WANG Jian lin,WU Ding rong,LIU Ling,LIU Jian dong
    2014, 35(02):  187-194.  doi:10.3969/j.issn.1000-6362.2014.02.011
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    The planting areas of winter wheat in Shandong province were divided into four regions by the newly developed statistical method,cluster analysis of statistical test (CAST).And models for forecasting winter wheat yield in each sub region were established and used to predict yield according to the climatic suitable index which based on temperature suitability,sunshine suitability,water suitability,that built by using winter wheat yield data,winter wheat growth data,daily meteorological data and moisture content data,from 1981 to 2011 Meanwhile,we compared it with the method of traditional contour partitions.The results indicated that,one region could not pass the significant test resulting in no prediction model with the method of contour line,and the average accuracy of others for historical forecasting was 94.2% and extrapolated forecasting was 92.3%.In relative terms,with the method of CAST,each region all passed the significant test and prediction models were established in each sub region,and the average accuracy for historical forecasting reached 95.8% and extrapolated forecasting reached 93.6%.The results showed that the yield prediction based on CAST was obviously superior to contour line and could provide an important way for fine yield prediction in agricultural meteorology.
    Exploration of Method in Separating Climatic Output Based on HP Filter
    WANG Gui zhi,LU Jin shuai,CHEN Ke yao,WU Xian hua
    2014, 35(02):  195-199.  doi:10.3969/j.issn.1000-6362.2014.02.012
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    In order to improve the accuracy of yield separation,the article attempted to apply the HP filter decomposition method to separating climatic output from long time sequence grain yield.The paper first considered three methods,HP filter,5-year moving average and Logistic fitting to construct the trend equations for the grain output respectively,based on the climatic output from 1961 to 2011.The three methods were compared by the trend changes and the fluctuation range.The results showed that the equations established by the three methods were all significant for the significance level 0.01.The output trend simulated by HP filter was coincided with the fact and appeared an obvious fluctuation in the research period,which reflected the characteristic of the actual yield.Meanwhile,the output trend simulated by 5-year moving average method was similar to that of HP filter method,but the changing range of the trend change was relatively slow.The output simulated by Logistic fitting was obviously higher than the actual yield and retained a growing status during the research period,which was different to the actual yield.It showed that,HP filter has more advantages to model the separating climatic output from long time sequence grain yield with,on one hand,the operating process is more easy and the climatic output simulated by this method agrees with the fact,on the other hand,the data had strong inclusiveness.
    Analysis on Safety Heading flowering Stage for Double Cropping Late Rice Based on Temporal and Spatial Features of Autumn Low Temperature
    PENG Li li,LU Kui dong,ZHANG Chao,HUANG Wan hua
    2014, 35(02):  200-205.  doi:10.3969/j.issn.1000-6362.2014.02.013
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    According to local standard,Meteorological Disaster Terminology and Classification of Hunan province,daily average temperature≤20℃(index I),≤22℃(index II)in 3 consecutive days or more was defined as the index of Autumn Low Temperature for conventional rice and hybrid rice,respectively.The earliest initial date of Autumn Low Temperature,the initial date for 50% year without Autumn Low Temperature,the initial date for 80% year without Autumn Low Temperature and daily frequency of Autumn Low Temperature were analyzed based on daily average temperature from 96 stations in Hunan province in September from 1951(the year of station construction)to 2010.The results showed that the earliest initial date of Autumn Low Temperature with index I was later 7-10 days than that of Autumn Low Temperature with index II Daily frequency of Autumn Low Temperature with index I was less than 5% in the first ten days and 10% in the middle ten days of September Daily frequency significantly increased in last ten days of September Daily frequency of Autumn Low Temperature with index II was less than 5% before September 8,then almost showed linear increase with time.The results indicated that the heading flowering stage delayed 3-5 days in north and center Hunan,so the medium late maturity rice was suggested to cultivate,instead of early maturing rice.
    Simulation of the Heat Injury on Rice Production in Jiangsu Province Under the Climate Change ScenariosⅡ:Adaptability Analysis of the Rice to Heat Injury From Booting to Heading Stage
    Wang Lian xi, Ren Jing quan, Li Qi
    2014, 35(02):  206-213.  doi:10.3969/j.issn.1000-6362.2014.02.014
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    Using the calibrated and combined CERESRice model and the weather data in the 2020s (20112040) of A2 and A1B climate change scenarios under the multi model dataset of Coupled Model Intercomparison Project phase 3(CMIP3),the adaptability of the rice to heat injury from booting to heading stage in Jiangsu province was studied by the means of the sowing date change (6d,12d,18d in advance,6d,12d, 18d delayed) and the cultivar parameter adjustment (G4=1.03, 1.06, 1.09, 1.12, 1.15).The results showed that,when the rice sowing date was 12d and 18d in advance,the rice yield increased most and the flowering date and growth period was extended compared with the baseline (19611990).On the contrary,when the sowing date was delayed, the rice yield declined and the flowering and growth period was shortened. Gaoyou was the biggest yield increase region and the yield increased by 13% under the A1B scenario, Lvsi was the biggest yield increase region under the A2 scenario, whose yield increased by 14%. When the G4 value was adjusted between 1.09 and 1.15, the rice yield of all station increased. The rice yield of Gaoyou increased 11% under the A1B scenario and the Ganyu station increased 7% under the A2 scenario. The growth period and flowering date were mainly extended. The rice yield increased more obvious while the sowing date was 12d in advance and the cultivar parameter G4 value was at 1.1. So, changing the sowing date and the cultivar parameter can improve the rice adaptability to the heat injury, which has the certain guide significance for the future rice production in Jiangsu province.
    Indices of Chilling Injury for Pitaya Seedling and Mature Plant
    GU Xiaoping,YUAN Xiaokang,HU Jiamin
    2014, 35(02):  214-220.  doi:10.3969/j.issn.1000-6362.2014.02.015
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    Taking seedlings and 6year trees of variety Zihonglong (Hylocereus polyrhizus Briton & Rose) as materials, five artificial environmental control experiments and one basis experiment were conducted in artificial climate chamber in September, 2012. The control experiment temperature was 2, 0, -2, -4 and -6℃, respectively, and the basis experiment was 20℃. At each experiment, relative electrical conductivity (REC), MDA content, SOD activity and soluble protein content of pitaya branch were measured after treatment 12 hours, and morphological changes were observed at the same time, in order to investigate the relationship between the factors and temperature and find the indices of chilling injury for pitaya. The results showed that seedlings and 6year trees damaged obvious at 0℃ and -2℃ respectively. The lower temperature was, the more obvious injury symptoms came out. REC and MDA content increased with temperature decline. SOD activity and soluble protein content increased at beginning and then decreased. The Logistic Model was used to fit the sigmoid curve between REC from plant tissues and temperature of treatments. Then the semi lethal temperature, which was -1.7℃ and -2.2℃, was determined by the model. The results indicated that the semi lethal temperature of seedlings and 6year trees were about -1.7℃ and -2.2℃, respectively. Low temperature damaged both seedlings and 6year trees, and the lower temperature was, the more badly injury would get. 6year trees could tolerate lower temperature than seedling. The results could provide scientific basis for chilling injury prevention and planting division of pitaya.
    Disaster Index of Continuous Overcast and Rainy Day During Mid and Late Growth Period of Summer Maize
    CHENG Lin, LIU Ronghua
    2014, 35(02):  221-227.  doi:10.3969/j.issn.1000-6362.2014.02.016
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    Taking summer maize in Henan province as an example, based on observed crop data during growing period from 1981 to 2010, yield data from 1961 to 2010, and daily meteorological data from 9 representative stations, 6 different types of continuous overcast and rainy days were designed. The relationship between yield reduction rate and overcast days during mid and late growth period of summer maize was analyzed by extracting yields reducing rate serials, selecting continuous rain days in lean years. The multiple linear regression equation for the effect of disaster on yield reduction was established, by comparing the high frequency overcast and rainy days and average value, the meteorological disaster index of continuous rain during flowering phase and grain filling phase for summer maize was determined respectively, and the possible yield loss rate was estimated. The results showed that, within the different grades of yield reduction rates, there was positive correlation between all kinds of continuous rain days and yield reduction rate 5%-20%, of which, the index of continuous lack of sunlight had high correlation with yield reduction rate between 5%-10%, while the index of continuous rain days had high correlation with yield reduction rate 15%-20%. Continuous rain or lack of sunlight at flowering stage had high correlation with yield reduction rate at grain filling stage. Meteorological disaster index of continuous rain was expressed by longest consecutive days without sunshine (N1), longest consecutive days of sunshine time less than 2 hours (N3), longest consecutive rain days (P1), longest combination days that consecutive rain and sunshine time less than 2 hours in rain free days (P3). The index was divided into two grades of light and heavy, and the average yield reduction rate under light disaster was 10.4% and 8.5% at flowering and grain filling stage respectively. The results could provide basic evidence for meteorological support service on high and stable yield of summer maize.
    Mapping Rice Paddy Distribution in Zhenjiang City Based on Multi temporal HJ-CCD Imagery
    GUO Jianmao,SHI Junyi
    2014, 35(02):  228-234.  doi:10.3969/j.issn.1000-6362.2014.02.017
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    The distribution of rice in Zhenjiang,Jiangsu province was separately extracted based on traditional empirical formula method and radiate transfer method Empirical formula method can be calculated by the statistical relationship between VI and LAINDVI and EVI were applied to establish the statistical model separately As for radiative transfer method,the PROSAIL model was adopted and LUT was established firstly Then the LAI of rice was determined through the comparison of the simulated reflectance data and the satellite remote sensing reflectance data The distribution of rice planting in Zhenjiang was determined by the phase distribution of LAI during the period of rice growth The results showed as followings:(1) by empirical formula method,Zhenjiangs rice area was 7.95×10.4 ha and relative error was 14.9%While by radiate transfer method,the rice area was 8.65×10.4 ha and relative error was 7.5% As a result,the result simulated by radiate transfer was closer to actual value than by traditional empirical formula method(2) In statistic model,the correlation between EVI and LAI was higher than the correlation between NDVI and LAI Thus,the result of further inversion of LAI would be more ideal when EVI-LAI method was used(3)The validation analysis of measured values showed that LAI RMSE inverted by statistical model was 1.32 and LAI RMSE inverted by PROSAIL model was 0.97So radiate transfer method was more stable than traditional empirical formula method when remote sensing inversion of vegetation biophysical parameters Research results of this paper are significant in the discussion of the application of traditional empirical formula method and radiate transfer method when crop distribution scopes are extracted Besides,results play an important role in accurate understanding of crops growth and planting area and have a good guidance for production