Research On The Spatial-temporal Distribution Of Growth Period Of Main Grain Crops And Its Change In China

China is one of the major agricultural producing countries in the world, its grain production gained the success that attract worldwide attention. But with the development of industrialization, the development of city and the increase of population, grain production situation is still grim. Grain production is a must for farming activities according to their own growth and development of crops, crop growth period is an important base for grain production activities of the frame of reference. The crop is a crop from sowing to harvest the whole growth and development need time, to explore the general law of crop growth and development, in-depth study of the crop growth period has important significance on understanding of agricultural production. According to the eating habits of people in our country, the rice, wheat, corn and other crops such as the 3 major grain crops in China; reference to the current scholars basis and status on the growth stage, the growth stage of the basis and standards; based on the extensive collection of statistical learning, meteorological data, agricultural chart and other data, the growth period data of main grain crops in different regions of China were summarized, and the establishment of the crop growth period of the original data and metadata database; data processing and classification of the original data collection and sorting, using the software of Arcgis 3 expression in the visualization of spatial distribution of crops, spatial and temporal distribution and variation of the obtained grain crop growth period.The main conclusions of this study are as follows:(1) A season high in the country have a growing, the growing stage of the start date is earlier than the North south. The growth period of nationwide law is increasing from northeast to southwest, in addition to the northwest, transplanting period basically is the number of days in low latitude, high latitude area is only a few days.(2) Double cropping rice in Qinling Mountains Huaihe line’s northern provinces basically no planting. The whole growth period of distribution, influence factors of double cropping rice growth period of days still to latitude location as the main, and the location of the land and sea and not much correlation.(3) Double cropping late rice growing provinces in the sowing time is concentrated in the year in mid June, this time node is usually between jointing stage and heading stage of transplanting paddy rice and early rice. Number of days with latitude factor of double cropping late rice growth period is closely related to, the specific performance of double cropping late rice growth period duration decreased with latitude and growing.(4) Of winter wheat planting area is very wide in China, North and South provinces of seeding interval is large, the northern provinces generally earlier sowing time. Qinling Mountains Huaihe line south of winter wheat planting provinces without going through the winter and reviving stage. On the whole, the whole growth period of winter wheat area time distribution in feature decreases gradually from northwest to Southeast significantly.(5) Spring wheat only accounts for the national total area planted in the proportion of about 6%, the basic law of the starting time of spring wheat seedling is the trend, from west to East, spring wheat emergence time was delayed. The starting time of spring wheat the presented clear characteristics.(6) In the national scope of the sowing time of corn is usually the year from February to May, south of the sowing time early, late sowing time in North area. The starting time of maize mature growth stage is still generally later than in the southern province of northern provinces. Corn seedling stage duration showed two areas of the north and South High low trend, the central region. Corn tasseling stage did not show obvious regularity of maize area, mature period and the whole growth duration from the southeast coast to the northwest inland gradually increase, but also from the low latitudes to high latitudes increased gradually.Through the analysis of the temporal and spatial distribution of main grain crops, in order to provide theoretical and practical reference and guide the agricultural production and management in the future. The thesis consists of five chapters:the first chapter is the introduction, introduces the research background and significance, elaborated the domestic and foreign related research progress and the research content and the technical route; the second chapter is the principle and the method, introduces the main methods of temporal and spatial distribution, this paper selected in this study,3 categories of 6 kinds of main food crops for and the main food crop growth stage; the third chapter is the empirical research, mainly includes the layout and spatial and temporal distribution of crop research area, data sources and processing, the main food crops; the fourth chapter is the analysis of factors affecting crop growth period, briefly discusses the effects of light, temperature, moisture and soil and other factors on crop growth period; the fifth chapter is the results and discussion, conclusion the overall research is summarized, and discussed based on the analysis of the data processing and data deficiencies, pointed out the growing point of further study.