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Table of Content

    20 December 2013, Volume 34 Issue 06
    论文
    Spatial and Temporal Variation of Meteorological Drought Days in Hunan Province
    ZHANG Jian ming,LIAO Yu fang,PENG Jia dong,ZHOU Jian jun,TAN Xiao
    2013, 34(06):  621-628.  doi:10.3969/j.issn.1000-6362.2013.06.001
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    The spatial and temporal distribution of meteorological drought days was analyzed by using of Empirical Orthogonal Function(EOF),Rotated Empirical Orthogonal Function(REOF)and wavelet analysis methods,based on daily meteorological data from 88 meteorological stations in Hunan province from 1960 to 2009,according to Comprehensive Meteorological Drought Index(CI)recommended by Classification of Meteorological Drought Category of GB/T20481-2006.The results showed that total meteorological drought days in southern Hunan were more than that of in northern Hunan.There were high value areas with the number of slight meteorological drought days in the upper and middle reaches of Xiangjiang river,northwest of Changde to Huaihua.The moderate meteorological drought days were in the central,north of southern Hunan and northern Hunan However,the severe meteorological drought days were in the central,southern,northern and western Hunan.The center of extreme meteorological drought days was in the Hengshao Basin.The spatial distribution of meteorological drought days was classified into five climatic types in whole province,including south Hunan,northeast,northwest,west and central Hunan,according to EOF and REOF analysis Meteorological drought days were not significant change in all climatic types in last 50 years,but they had an obvious interannual variability.Meteorological drought days in the west Hunan have decreased since the beginning of 21st century,but those in other four climate types have increased.There was an obvious periods of 2-3years and 4-6years according to Morlet wavelet analysis.The results could provide the scientific basis for drought resistant countermeasures in Hunan province.
    Effects of Simulated Warming and Precipitation Enhancement on Soil Respiration of Stipa krylovii Steppe
    ZHANG Li xin,YANG Jie,GAO Qing zhu,SU Li de,Ganjur jav,HOU Hong
    2013, 34(06):  629-635.  doi:10.3969/j.issn.1000-6362.2013.06.002
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    In this study,authors conducted experiments for two growing seasons(2011 and 2012)in Stipa krylovii Steppe,Inner Mongolia,China Using open top chambers(OTCs)to simulate warming and precipitation enhancement.To study the effects of climate warming and increasing precipitation and the interaction on soil respiration of S krylovii Steppe.The results showed that:(1)both the diurnal change and daily variation pattern of soil respiration rate had a single peak,the highest respiration rate appeared in the 15:00pm in diurnal(2.26μmol·m-2·s-1)and late August in the growing season(5.51μmol·m-2·s-1).Soil respiration rate of 9:00-11:00 can better represent the mean of all day.⑵Compared with the control,soil respiration rate reduced 19.0% when the air temperature increasing 1.91℃,but increased 18.6% under precipitation enhancement treatment(increase precipitation 20%).Warming and precipitation enhancement treatment(increase air temperature 1.64℃,and increase precipitation 20%)increased 13.0% soil respiration rate compared with the control.(3)There were significant relationship among soil moisture,soil temperature and soil respiration rate.About 79% of soil respiration change was determined by the soil temperature and soil moisture,but the mainly influencing factor was soil moisture content(R2=0.797,P<0.001).Warming resulted in reduced soil moisture,indirectly led to the soil respiration rate decline.The results can provide the basis for the sustainable development of the science of climate change and the typical steppe grassland animal husbandry.
    Impacts of Infrared Heating on CO2 Emission from Soybean Ecosystem
    HU Zheng hua,CUI Hai ling,ZHOU Ying ping,CHEN Shu tao,SHEN Shuang he
    2013, 34(06):  636-641.  doi:10.3969/j.issn.1000-6362.2013.06.003
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    To investigate the impact of infrared heating on CO2 emission from soil and soybean soil system,the field experiment was carried out during soybean growing season CO2 fluxes were measured by static dark chamber gas chromatograph method.The results showed that infrared heating 2℃(T)had a positive effect on soil CO2 fluxes,which increased by 87.21% during maturity stage,from 202.09±28.75mg·m-2·h-1 to 378.34±156.17mg·m-2·h-1,but no significant difference was found;T increased significantly the cumulative amount of CO2 from soil by 39.96%.In addition,the Q10(temperature sensitivity coefficients)for soybean soil system’s respiration under the control and T treatments were 0.68 and 2.54,respectively,while the Q10 for soil respiration were 4.22 and 1.68,respectively.The results suggest that infrared heating may lead to an increase in soil CO2 emission and the Q10 for soybean soil systems respiration,and a decrease in the Q 10 for soil respiration.This study will provide the base to estimate the regional farmland greenhouse gas emission.
    Effects of Decreasing Nitrogen Inputs on Nitrate Nitrogen in Soil and Nitrogen Fertilizer Use Efficiency
    WANG Cheng yu,SHI Yu hua,JING Yue bo
    2013, 34(06):  642-647.  doi:10.3969/j.issn.1000-6362.2013.06.004
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    A two year experiment was conducted to investigate the differences of net photosynthetic rate(Pn)of the flag leaves,wheat yield,nitrate nitrogen(N)in soil and N fertilizer use efficiencies,including apparent recovery efficiency of applied N(REN),agronomic efficiency of applied N(AEN),physiological efficiency of applied N(PEN),partial factor productivity of applied N(PFPN)for winter wheat under three treatments:no N treatment(T1),decreasing N treatment(T2,180kg·ha-1N)and conventional N treatment(T3,315kg·ha-1N)with two different growing seasons,represented by T11,T21and T31 in 2008/2009 and T12,T22 and T32 in 2009/2010,respectively.The results showed that,(1)the differences of the photosynthesis of flag leaves(Pn)and yield of Jimai22 were not significant between T21 and T31,as well as between T22 and T32,which all significant higher than T11 and T12.(2)The content of nitrate N in 0-200cm soil layer under T22 at harvest was significant lower than that under T32 and T21,and the decreased rates were 32.2% and 26.7%,respectively.(3)REN,AEN,PEN and PFPN under T22 were significant higher than those under T32 and higher than REN,AEN and PEN except PFPN under T21 as well.For no reductions of the Pn of flag leaves and yield for Jinmai22,180kg·ha-1 N is a reasonable value for the farmer with decreasing the risk of groundwater pollution and promoting fertilizer N use efficiency compared with the conventional N treatment.The research results can provide a theoretical basis for sustainable development of high nitrogen utilization and winter wheat cultivation.
    Spatial and Temporal Variation of Irrigation Water Requirement for Winter Wheat in Jijingjin Region
    HU Wei,YAN Chang rong,LI Ying chun,ZHOU Yuan hua,LIU Qin
    2013, 34(06):  648-654.  doi:10.3969/j.issn.1000-6362.2013.06.005
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    Temporal and spatial distribution characteristics of crop water requirement and irrigation water requirement are the bases for determining the irrigation quota in different regions.The objective of this study is to analyze irrigation water requirement of winter wheat in growth stages to improve the efficiency and productivity of irrigation water in Jijingjin region,and to ensure the food security.Based on data from 20 meteorological stations during 1961 to 2010 and phonological data of winter wheat during 1980 to 2009,using the Penman Monteith method recommended by FAO,the spatial pattern of the reference crop evapotranspiration was calculated and water requirement in different growth stages for winter wheat were analyzed.And the irrigation water requirement distribution of winter wheat during different growth stages in Jijingjin region during the recent 50 years were analyzed using the crop water surplus deficit index.The results showed that the effective rainfall of winter wheat during the different growth stages and the whole growing period was increasing,while the water demand of winter wheat during the different growth stages and the whole growing period showed a decreasing trend.There was a significant shrinking tendency during heading to milk ripe stage.The change of the effective rainfall and water demand would promote the evolution on agricultural irrigation.To meet the need for the growth of winter wheat,the total supplementary irrigation amount was around 291 to 381mm.More irrigation water requirement of region was in the city of Cangzhou and Hengshui.Some specific differences also existed in supplementary irrigation water condition and short term change.Respectively,the period of the more supplementary irrigation was jointing to heading stage which declined from the center of Cangzhou city and heading milk stage which increased from the north to the south.The conclusions were important to be applied to the monitoring of water change and provide theoretical basis for strategies of guiding the irrigation timing and amount.
    Effects of Moisture Stress on Photosynthetic Characteristics of Summer Maize Leaf  during Growth Stages
    TIAN Lin, XIE Xiao jin, BAO Yun xuan, HU Ji chao, YU Li, WANG Jin xin
    2013, 34(06):  655-660.  doi:10.3969/j.issn.1000-6362.2013.06.006
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    The morphology structure and photosynthetic characteristics of summer maize (Suyu20 and Zhengdan958) were studied during different growth stages under different water stresses (drought stress, flooding stress and control environment) in potting experiment. The results showed that soil and plant analyzer development (SPAD) value, net photosynthetic rate (NPn), transpiration rate (Tr) and conductance to H2O (Gs) decreased, and the intercellular CO2concentration (Ci) increased under water stresses. The sensitive degrees of two summer maize cultivars to water stresses at tasseling stage were higher than those at jointing stage, and they were further higher to flooding stress than those to drought stress. The drought resistance of Suyu20 was similar to Zhengdan958 at different growth stages, but the flooding resistance of Suyu20 was lower than Zhengdan958. The results provided a theoretical basis for maize water stress research in different regions.
    Variation of Reference Crop Evapotranspiration and Contribution of Main Factors in the Huaihe Basin
    WANG Xiao dong,MA Xiao qun,XU Ying,LIU Rui na,CAO Wen,ZHU Hao
    2013, 34(06):  661-667.  doi:10.3969/j.issn.1000-6362.2013.06.007
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    The reference crop evapotranspiration(ET0)in Huaihe basin was calculated based on observed data from 171 meteorological stations from 1971 to 2010 by using of FAO Penman Monteith equation The Spatial and temporal distribution characteristics of ET0 and influencing factors were analyzed The results showed that average ET0 in Huaihe basin was 898mm and decreased at the rate of 17.5mm/10y(P<0.05)in past 40 years Most stations in northwest decreased significantly(P<0.05)and seldom stations in southeast were increased significantly(P<0.05)The contribution to ET0 of the meteorological factors displayed in two aspects,which including sensitivity and relative change rate of the meteorological factors The sensitivity analysis showed relative humidity was the most sensitive among the four main meteorological factors(average temperature,relative humidity,sunshine hours and wind speed),but the average wind speed changed most Wind speed had large contribution to ET0,as average temperature was little The total contribution of 4 factors to ET0 was-4.96,which meant decreased of ET0The result was beneficial to evaluate agricultural water resources and take appropriate measures
    Effects of Silicon Fertilization on Diurnal Variations of Photosynthesis and Transpiration at Barley Heading Stage under Elevated UVB Radiation
    LOU Yun sheng,HAN Yan,LIU Zhao yang,MENG Yan,WU Lei
    2013, 34(06):  668-672.  doi:10.3969/j.issn.1000-6362.2013.06.008
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    Field simulating experiment with barley was conducted to investigate the effects of silicon(Si)supply on diurnal variations of net photosynthetic rate(Pn),transpiration rate(Tr),stomatal conductivity(Gs),intercellular CO2 concentration(Ci)and water use efficiency(WUE)under elevated UVB radiation The experiment was designed with two UVB radiation levels,ieambient(A,1.5kJ·m-2)and elevated UVB(E,1.8kJ·m-2),and two Si supply levels,ieSi0(0kg·ha-1 SiO2)and Si1(150kg·ha-1 SiO2)The results showed that,compared with ambient UVB radiation,elevated UVB radiation decreased net photosynthetic rate,transpiration rate,stomatal conductivity and water use efficiency by 23.13%,7.66%,1.07% and 16.38% under Si0 level,respectively,and reduced by 10.52%,5.71%,3.77% and 12.15% under Si1 level,respectively This finding suggested that elevated UVB radiation depressed net photosynthetic rate,transpiration rate and water use efficiency in barley leaves,increasing Si supply could alleviate the damage to net photosynthetic rate from elevated UVB radiation,but not to transpiration rate and stomatal conductivity This research will be helpful in further investigating the effect of Si supply on barley yield and quality under elevated UVB radiation.
    Analysis on the Suitable Climatic Factors of  Sophora tonkinensis Gapnep. in Guangxi
    YAO Shao chang, LING Zheng zhu, LAN Zu zai, MIAO Jian hua
    2013, 34(06):  673-677.  doi:10.3969/j.issn.1000-6362.2013.02.009
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    According to the mean climatic data of 30 years and contents of alkaloid from 7 wild plant distribution areas in total 21 individuals, the quantitative relationship between climatic factors and contents of alkaloid was researched by stepwise regression analysis, partial correlation analysis and path analysis methods. The results showed that the leading climatic factors that affected contents of alkaloid were annual mean temperature, mean extreme maximum temperature in June, July, August and annual average mean rainfall, which had determined 95.24% of alkaloid content. The main stimulative factor was annual average mean rainfall and the main limited one was mean extreme maximum temperature in August. Annual mean temperature (<20℃), mean extreme maximum temperature (<35℃) and annual mean average rainfall (>1500mm) were the suitable climatic factors for  Sophora tonkinensis. This research could provide theoretical basis for the production of high quality  Sophora tonkinensis, also for optimizing herb production and regulating herb quality.
    Effects of Water Logging on Morphological Characteristics and Yield of Hybrid Rice during Growth Stages
    NING Jin hua,HUO Zhi guo,LU Kui dong,HUANG Wan hua,LIU Bin yu,SHEN Jun you
    2013, 34(06):  678-684.  doi:10.3969/j.issn.1000-6362.2013.06.010
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    Water logging stress experiment was conducted at heading flowering stage and milk stage of hybrid rice Xiang Feng You 103Sensitivity of hybrid rice to water logging stress at different growth stages was analyzed,through comparing green leaf number,aerial root,lodging conditions and yield components before and after different flooding treatments The results showed that green leaf number was extreme significant negative correlation with the depth of  water logging The ratio of aerial root stem was negative correlation with flooding depth and positive correlation with flooding duration Aerial root was more as lower the stem nodes,especially at heading flowering stage Stem lodging occurred at heading flowering stage,and there was a significant positive correlation between the percentage of stem lodging and water logging duration Root lodging occurred at milk stage,and it was worse with water logging deeper and longer The sensitivity of hybrid rice to water logging stress at heading flowering stage was more than that at milky stage Yield was failure with water logging stress for 5 days at this stage The research results could be used as evaluation standard of flood disaster to hybrid rice
    Preestimating the Yields of Three Major Crops in Inner Mongolia under the Numerical Simulation Scenarios for the Future 30 Years
    GAO Tao, YANG Ze long, WEI Yu rong, YAN Wei, CHEN Yan cai
    2013, 34(06):  685-695.  doi:10.3969/j.issn.1000-6362.2013.06.011
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    The datasets of the daily precipitation and temperature at 58 stations in the cultivating areas in Inner Mongolia for the past 50 years (1961-2010) and the yield perunit records of 38 leagues (cities) for the past 48 years (1961-2008) of wheat, 30 years (1979-2008) of maize and potato were collected, investigated and analyzed for preestimating the variations of the three major crop yields for the future 30 years (2011-2040) In this research, the authors utilized natural logarithm function to present the crop trend yield, and then separated the meteorological yield from the observed yield series Furthermore, results of the multiple linear regressions indicated that the growing season precipitation and temperature made significant impacts on the three major crops in most leagues (cities) of Inner Mongolia In addition, regional climate simulating outputs of the PRECIS under the SRES for A1B, A2 and B2 emission scenarios, and the CMIP5 multi model dataset were employed to simulate climate conditions for the future 30 years The meteorological yield, simulated temperature and precipitation for all leagues (cities) were composed into the multiple linear regression models for preestimating the coming 30 years meteorological yield of the three crops The regression results indicated that all meteorological yields perform an increasing trend, though in several years display decreased yield The preestimated quantity of meteorological yield perunit for wheat, maize and potato would respectively increase about 1790, 516 and 507kg/ha during the future 30 years The yield displayed an uptrend in all leagues(cities) after the natural logarithm trend yield to be added into the meteorological yield series, and the yield predicted would increase by 12214, 21211 and 10080kg/ha for wheat, maize and potato wheat Results of this study can be referenced as important scientific information for facing future climate change and making developing policy for future crop production
    Evaluation Method for Winter Wheat Yield Loss of Drought Disaster in North China
    TAN Fang ying, WANG Jian lin, ZHENG Chang ling, SONG Yan ling, YANG Fei yun SONG Ying bo
    2013, 34(06):  696-702.  doi:10.3969/j.issn.1000-6362.2013.02.012
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    The North China was divided into fifteen regions according to similarity principle of climate and agricultural production level The daily meteorological drought composite indices (CI) were calculated based on the daily temperature and precipitation data of observation stations from 1970 to 2010, and the contiguous soil moisture status observation data was converted into daily data by using simplified linear interpolation method The evaluation criterion of CI for winter wheat in drought was revised according to the regions and growth stages by comparing of CI and daily soil moisture data, and standard cumulative indices of drought was established based on new indices The evaluation model of yield loss in drought for winter wheat was established, considering to unit yield data of winter wheat The results showed that the change of daily CI index was similar to that of soil moisture, and the corrected indices of 15 regions were quite different from the discrimination standards of meteorological drought composite indices (CI indices) Drought indices varied among regions, which was lower in western Henan, northern Shandong, southeast Shandong, Beijing, Tianjin and mideastern Henan, and higher in middle Shandong, northeast Hebei, middle Hebei and south Hebei The evaluation models of yield loss in drought for winter wheat in 15 regions passed the 0.05 significance test, and the standard cumulative index of drought was significantly correlated to winter wheat yield loss It was significant between historical evaluation results and yield loss of drought (P<0.05) in Beijing, Tianjin, middle Shanxi, south Shanxi, middle Shandong, southeast Shandong and west Henan The evaluation models evaluated the yield loss in drought for winter wheat accurately, and the results could used for practice.
    Low Temperature Risk Division in Winter for Protected Agriculture in Anhui Province
    LI De, YANG Tai ming, LIU Rui na, MA Xiao qun
    2013, 34(06):  703-709.  doi:10.3969/j.issn.1000-6362.2013.06.013
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    The layout of protected agriculture types was identified by using mathematical statistics, based on observed meteorological data in winter from 29 representative meteorological stations in Anhui province from 1960 to 2010 The comprehensive risk index of low temperature was established with 4 parameters, including climatic probability and its volatility of annual extreme low temperature, occurrence intensity and average days of daily lowest temperature in winter The results showed that it was not suitable for small plastic arch shed if risk probability of extreme low temperature (<50℃) was more than 80% If the risk probability of extreme low temperature (<100℃) was more than 20%, where located along Huaihe river, it was suitable to plastic sheeting in south region and suitable to sunlight greenhouse in north region The comprehensive risk index of low temperature was divided into 5 grades, no effect, slight, moderate, severe and extra severe respectively Slight and moderate damage was dominated in south of Huaihe river and moderate and severe damage was dominated in north of Huaihe river.
    Experimental Research on Meteorological Index of High Temperature Damage to Early Rice at the Early Milk Stage
    TIAN Jun, NIE Qiu sheng, CUI Hai jian
    2013, 34(06):  710-714.  doi:10.3969/j.issn.1000-6362.2013.06.014
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    In order to study meteorological index of high temperature damage to early rice at the early milk stage, the control trials of daily maximum temperature (between 34℃ and 39℃) of hybrid rice Ganxin 203 at the early milk stage were carried out in the climatic cabinets. And the natural temperature was taken as the contrast. The ripening rate, blighted grain rate, 1000 grains weight and yield per plant of each material, which were closely related with high temperature damage to early rice at the early milk stage, were analyzed by using principal component analysis and hierarchical cluster analysis. The results showed that the meteorological index of high temperature damage to early rice at the early milk stage could be classified into three grades, including light, moderate and severe damage, that was, daily maximum temperature of 35℃ for 5 days, or 36℃ for 4 days, or 37℃ for 3-4 days, or not less than 38℃ for 3 days belonged to light damage,daily maximum temperature of 35℃ for 6-8 days, or between 36 and 37℃ for 5 days, or not less than 38℃ for 4-5 days belonged to moderate damage; daily maximum temperature of 35℃ for greater than 8 days, or not less than 36℃ for 6 days and above belonged to severe damage. Relative to original index, the new index, which considered not only the high temperature strength and duration, but also their coordination, was more sensitive to the identification of heat damage, and every damage grade had its daily maximum temperature and duration. The results could support scientific foundations for monitoring and warning, risk assessment and division of high temperature damage to early rice.
    The Refined Risk Division of Maize Chilling Damage in Eastern Inner Mongolia Based on GIS
    WANG Zhi chun, YANG Jun, JIANG Xiao fang, XU Zhen yu, WEI Xue
    2013, 34(06):  715-719.  doi:10.3969/j.issn.1000-6362.2013.06.015
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    The comprehensive risk index of maize chilling damage in eastern Inner Mongolia was established through the analysis of the frequency of chilling damages and the variation of heat condition. The refined risk division map of maize chilling damage was obtained by using of space prediction model based on GIS and 150000 geography information. The results showed that the highest risk areas was in the northern and western Hulunbeier, where located in high altitude and latitudethe lowest risk areas was in the middle and southern Tongliao, southeastern Chifeng and southern Xing'an league, where located in low altitude and flat terrain. The risk degree of chilling damage distributed from northwest to southeast in eastern Inner Mongolia. However, the risk distribution of chilling damage was scattered as influenced by the factors of altitude, latitude, terrain and topography. The research result was beneficial to avoid to maize chilling damage risk, and it was also beneficial to utilize potential climate resources, and optimize planting structure and distribution.
    Grain Yield Estimation Models and Loss Analysis Based on Agrometeorological Disaster Exposure in Northeast China
    WANG Jian, LIU Bu chun, LIU Yuan, YANG Xiao juan, BAI Wei
    2013, 34(06):  720-726.  doi:10.3969/j.issn.1000-6362.2013.06.016
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    he model for estimating grain yield was established, through analyzing the relationship between climatic grain loss and disaster exposure by using multiple regression method based on the statistical data of agro meteorological disaster exposure and grain yield in Northeast China from 1981 to 2010. Meanwhile, the impact of drought, flood, low temperature and wind-hail on grain loss was evaluated by using grey relational analysis on the slight, moderate and severe damage level respectively. The results showed that there was significant correlation between climatic grain loss and statistical data of agrometeorological disaster exposure (P<0.01). The coefficients of determination (R2) of regression models were 0.76 (Heilongjiang province), 0.78 (Jilin province) and 0.87 (Liaoning province), and their average relative errors between simulated yield and real yield were -0.06%, -0.32% and -0.20% respectively. The results indicated that statistical data of agrometeorological disaster exposure was a good indicator for predicting regional grain loss and grain yield while the meteorological disaster occurred. They were dependable basis for estimating of regional grain yield and evaluating of agrometeorological disasters. The results of grey relational analysis showed that the correlation degrees between drought and grain loss were the maximum in three provinces on the slight damage level, the correlation degrees between windhail and grain loss were the maximum in three provinces on the moderate and severe damage level, the correlation degrees between low temperature and grain loss were not the maximum. Therefore, the main meteorological disaster was light degree and wide range of drought or strong and local based wind hail. However, as one of the most obvious warming regions, low temperature was no longer the most important disaster in Northeast China.
    Spectral Monitoring Model of Leaf/Canopy Stomatal Conductance in Maize under Different Soil Moisture Treatments
    LIU Fan, SHEN Shuang he, YANG Bing yu, TAO Su lin
    2013, 34(06):  727-732.  doi:10.3969/j.issn.1000-6362.2013.06.017
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    The artificially controlled soil moisture experiments were performed in different growth periods on maize to measure the leaf stomatal conductance, leaf area index and canopy spectral reflectance. Then the changes in leaf stomatal conductance and the correlation relationships between the canopy spectral reflectance indices as well as leaf stomatal conductance were analyzed to construct leaf stomatal conductance models with considering the spectral vegetation index and soil moisture. The results indicated that the canopy reflectance of maize in visible and near medium and long infrared spectrum regions was increasing with the decreasing of soil moisture, while the stomatal conductance (Gs), leaf area index (LAI), ratio vegetation index (RVI) and normalized difference vegetation index (NDVI) were reducing. And the exponential functions and significantly positive correlations between NDVI/RVI and leaf/canopy stomatal conductance were also investigated. Furthermore, the spectral vegetation index better fitted into leaf stomatal conductance than into canopy stomatal conductance and the leaf stomatal conductance model with the consideration of RVI and soil moisture performed better than that with the consideration of NDVI and soil moisture. Thus the stomatal conductance in maize might be monitored real-timely, rapidly and quantitatively based on the canopy spectral reflectance and the work in this study could be fundamental to estimate crop stomatal conductance in large scales.