The Planting Of Winter Wheat To Adapt To Climate Change In Beijing And Varieties Tested

Agriculture ecosystem is an important part of the ecosystem, the agricultural ecosystem diversity has not been given much attention. It is the opportunity for the structural adjustment of agricultural planting because of the global warming, and it is necessary to take advantage of this opportunity by planting different varieties to improve the grain yield and the diversity of agricultural ecosystem. This study analyses the climate change in Beijing area and agriculture heat resource changes using the daily weather data since1951, explores the optimum sowing date and gene varieties, and vertifies the role of gene varieties diversity in stabilizing agricultural ecosystems.31winter wheat gene varieties were planted (4types of winter wheat) in3sowing dates (September25th, October7th and October17th in2011). The main conclusions are as follows:1. The winter wheat gene variety and sowing date can be adjusted to the conditions of climate and heat resources in Beijing area.The annual average temperature, the annual maximum temperature, the annual minimum temperature of the coldest month average temperature and the lowest temperatue in Beijing area show an upward trend. The average temperature rising rate is0.41℃/10a, annual maximum temperature warming rate is0.12℃/10a, and annual minimum temperature warming rate is0.96℃/10a, which is fastest. The rising rate of the average temperature in January is consistent with that of the annual mean temperature,0.42℃/10a.The rising rates of the autumnal equinox and Bailu solar terms are higher than0.40℃/10a, and the rising rate of the cold dew solar terms is only0.17℃/10, the average temperature of the autumnal equinox is higher than the best temperature for winter variety sowing. The traditional sowing date is not adapt to today’s actual production.The beginning of the winter for winter wheat delays and the ending of the winter advances, which means the winter duration is shorter. The absolute value of the winter accumulated temperature reducs because of the winter duration and the climate warming. But the cold acclimation before winter wheat remains at medium level.The number of the occurrence of the dry hot wind is more than that of the cold wave, the dry hot wind is to be the most influential meteorological disasters for the winter wheat. As the climate warms, the number of the occurrences of cold wave reduces gradually, and the number of the occurrences of hot wind unchanges, the high-incidence dates prones from mid-May and late-May to early June, which ss not conducive to late filling stage of winter wheat, especially for late-maturing varieties.With the global warming, winter wheat growth period in Beijing area has a tendency to delay before winter, and the the growth period has a tendency to be in advance, the whole growth period is significantly shortened, the vegetative growth stage is shorten,and the reproductive growth phase is extended (the filling stage).2. With the climate warming, the springness trend of the winter wheat has begun to emerge in Beijing in the normal warm year. Taking the adaptation measures such as sowing date and varietie change can play a regulatory role in the duration and the required temperature of winter wheat and the rich diversity of agricultural ecological system, maintain the stability of the ecosystem, and promote the yield of winter wheat. 1) The sowing date postponed and the selection of winter weaker species to cope with the climate change can be used in Beijing suburban plain area in the normal warm year which can inprove the production, and increase the risk of the dry hot wind.The probability of strong seeding is highest if the wheat is planted in the end of September, but the probability of much strong seeding is also highest. If the wheat is sowed before the mid-October, the accumulated temperature is good for strong sprout before winter. From the field test, the seedings of all the varieties were not much strong and the spring varieties grow normally which were planted by the end of September, but turning green survival rate of the spring varieties was low, the growth stage of the spring varieties can be observed. All the varieties can survival after winter which were planted in mid-October.The sowing date postponed, the growth process of winter wheat is accelerated, the difference in the mature period is small, and the change rate decreases from the flag, heading to blossom periods, the growth period of partial winter wheat is much stable than that of partial spring variety. The whole growth period of winter wheat decreases with the delay of sowing date, the shorten of the whole growth period mainly due to the differences in growth period before winter, the shortening amplitude of partial spring wheat is bigger. During the winter wheat germ (blossom to maturity stage) stage, the durantion of the partial winter varieties increases with the sowing date postponed, the duation of partial spring varieties decreased with the delay of sowing date, so the risk of dry spring is greater in partial varieties.2) Sowing and varieties change of winter wheat can adjust the accumulated duration and the adjustment required in the growth stages, but the role of sowing and varieties is opposite.Whether or not considering the adjustment of varieties, the sowing seedling-emergence stage, the heading stage-maturity stage and the whole growth period of winter wheat have the tendency to reduce, the adjustment of varieties will alleviate this trend, and the sowing date postponed will expand this trend. Whether or not considering the adjustment of varieties, the sowing seedling-emergence stage, the egergence-tillering stage, the over-wintering stage, the heading stage-maturity stage and the whole growth period of winter wheat require much accumulated temperature, the adjustment of varieties will expand the trend, and the sowing date postponed will reduce this trend.3) The winter and semi-winter varieties sown before mid-October, the yield is highes.In Beijing area, semi-winter varieties can be planted after the end of September, and the yield is highest. The yield of the end of September and the mid-October is the same, but in the mid-October, partial spring varieties can be planted. Most of the spring varieties are also not suitable for planting at the end of September.In the current climate conditions, winter and semi-winter wheat planted before mid-October, the yield is highest. The yield improvement depends mainly on the panicles.