Dynamic Assessment Of Cold Damage Risk For Rice Based On CERES-Rice Model In Eastern Jilin Province,China

Rice is one of the most important subsistence crops, northeast region of rice cold damage is the most frequent areas, rice production safety is directly related to the production of safe food. Risk is the possibility of cold damage caused by chilling injury and loss, depending on the risk of low temperature, vulnerability, exposure and local disaster prevention and mitigation of these four factors. This article from the formation mechanism of disaster risk, default within a certain time of exposure and the local disaster prevention and mitigation of hazard bearing body unchanged, cold damage risk depends on the risk of hypothermia and the vulnerability of hazard bearing body.In this paper, rice cold damage in eastern Jilin province were analyzed background, analysis of rice cold damage disaster-environmental complexity, hazard factor changes, the vulnerability of hazard bearing body and exposure status. The use of 10 meteorological stations in the eastern part of Jilin Province 1961-2010 years of daily temperature data and rice cultivation information, In CMA 2013 release of rice cold damage assessment technical specification (QX/T182-2013) industry standard in different thermal zones in Northeast May to September the average temperature of the rice and the anomaly is delayed cold damage index, in daily low temperature accumulated value as rice obstacle type cold damage indicators. Analysis eastern Jilin province rice delayed cold damage and distribution of spatial barriers type cold damage occurred. Use EOF, wavelet transform analysis of the distribution of rice in eastern Jilin province cold damage time and space as a whole. We were established rice obstacles and delayed cold damage risk index. The use of spatial interpolation techniques, methods M-K mutation analysis of the trend test and eastern Jilin province rice delayed cold damage and obstacles cold disaster risk index were analyzed temporal characteristics. Vulnerability is used to reflect the possibility of hazard bearing body stress caused by the stress factors of loss, is the key factors affect the formation of disaster risk, is connected to the bridge disaster risk and disaster. From the nature of the vulnerability of rice to start, based on the field trial data, cold damage hazard intensity as abscissa, the loss rate of rice production in different growth stages on the final play a key role in physiological indicators as ordinate, to build rice different growth stages based on field trials cold damage vulnerability curve, daily application of CERES-Rice model by frame simulation rice growth process, select a typical case of cold damage and mean years of meteorological data as model input, excluding the impact of water stress, loss rate calculation different rice growth stages due to the cold damage caused by the key physiological indicators, final fitting on different rice growth stages vulnerability curve based on CERES-Rice model. Two ways of constructing vulnerability curve can complement each other. The result of the field trials is a test to the model calculation results. According to disaster risk evaluation techniques, based on crop growth simulation model, coupled cold damage risk hazard and vulnerability of rice, constructed the cold damage risk dynamic evaluation model at rice different growth stages, using GIS technology to draw different growth stages of rice cold damage risk zoning map. The results showed that:Dunhua areas rice transplanting-booting stage cold damage with the highest risk level; Changbai, Donggang, Erdao is the highest level of disaster risk regions in rice Booting-Heading-Blooming stage; Analyzed the cold damage in rice production and rice each growth stage cold damage risk value relevance, there is a certain linear relationship between the yield reduction rate and risk value, and each growth period have passed the test Fa= 0.05, the risk assessment model is scientific and rational, results of the risk assessment also passed significant verification. Finally, the eastern part of Jilin Province Rice cold damage risk management measures, cold tolerance in rice select better varieties of rice on the calendar before deep irrigation to give the amount of nitrogen fertilizer 120kg/hm2 by block experiment before Nitrogen way turn 90%+10% of reviving rice cold damage control technology for the optimal combination of the above methods can reduce the risk of rice cold damage.Traditional rice cold damage risk study, based on rice risk assessment theory cold damage dynamic risk assessment studies seldom present study different growth stages of rice, rice cold damage implementation of real-time, dynamic rating indicates growth period, rice chilling injury occurred provide early warning aura, either prediction area of rice cold damage occurrence and intensity, can also estimate the varying degrees of cold damage it may cause loss of crop production, achieve rice cold damage risk in real-time warning.