Spatial-temporal Characteristics Of Alfafa Low Temperature Injuries In Inner Mongolia Of Recent 65 Years

This research focused on the frequently occurring low temperature injuries(LTI)of cultivated alfafa in Inner Mongolia.it will be not only helpful to meet the knowledge of both the yield and quality formation and the mitigations of the loss of LTI,but also be worthy to further exploring the impact of LTI to the figure and the productivity of alfafa and doing researches of alfafa hazards' regionalization and growth model.So as to formatting the guidance of alfafa production.On the view of compound disasters' system analyzing,this research made the classification and evaluation system of frequently occurring LTI in cultivated alfafa of Inner Mongolia.By exploring the means of R-Language and MySQL integrated by the API of ODBC5.3 and Navicat for MySQL,this research rescued the bottleneck of high-order analyzing and reshipment of data of multi-resources.On the base of building a database of both main phenological period and all kinds of LTI of alfafa,this research employed the methods of the analysis of time series based on the characteristic indexes of time series and the wavelet analysis of representative stations,this process incorporated with the indexes of linear trend,change variance,happening rate and mean strength and so on.Finally established a theory of the spatial-temporal characteristics of yearly strength of LTI and main phenological period of alfafa between 1951 and 2016,and further analyzed the response mechanism of LTI in climate change.The results showed that:1.The long term frost injury(LTFI)strike the regions of higher latitude such as XilinGol,Western XingAn and HulunBuir seriously.It was almost weakened in Inner Mongolia,however,the server LTFI weakened in the above regions of high occurrence,but enhanced in XilinGol and Hetao.2.The thawing-freezing injury(TFI)strikes the Eastern Alashan,Hetao and Western Ordos seriously,the almost TFI strength weakened in the above regions of high occurrence,but the server TFI strength enhanced in mostly Inner Mongolia.3.The yearly strength of obstacle cool injury(OCI)enhanced in the regions of high occurrence such as Ordos,the northern Huhhot and Baotou,Ulanquab,the southern XilinGol and Chifeng,the Western XingAn,but weakened in the regions of shorter occurrence such as Huhhot and Baotou,the middle and north part of XilinGol and Chifeng,the western HulunBuir.4.The spring cold injury(SPI)strikes the western Inner Mongolia more than the eastern.The strength of SPI enhanced in western Inner Mongolia but weakened in the eastern;the serious yearly SPI strength weakened in mostly Inner Mongolia,while enhanced in the eastern Alashan,the southern of XilinGol and Chifeng.5.The delayed cold injury(DCI)strikes the eastern Inner Mongolia,which locates in higher latitude seriously.The yearly strength of DCI weakened in mostly Inner Mongolia,but enhanced in the southern Ulanquab and Chifeng,the western XingAn.6.The Autumn cold injury(ACI)strikes Alashan,the western Ordos,Hetao,the western Chifeng and Tongliao seriously.The yearly strength of ACI weakened in mostly Inner Mongolia.7.The strength of LTIs of alfafa were strongly controlled by cycles of 5 to 15 and 20 to 30,the shorten tendency of them enlarged the strength of LTFI in Ordos and the heavy and extreme strength of DCI in Ulanquab;around the recent 65 years,the strengths of alfafa LTFI and the LTIs after the late April weakened;the strengths of LTIs in alfafa sprouted phase earlier stage of alfafa spring growth closely relates to the phenological advancement and the time and extent of physiological sensitive stages.