Analysis On Potential Productivity Of Crops And Change Of Planting Structure Under The Background Of Climate Change In Ningxia

This study based on the monthly meteorological data about temperature, precipitation, sunshine duration and wind speed of 23 meteorological stations during 1961 to 2012 and the vector map of county in Ningxia. The photosynthetic, light and temperature, climatic potential productivity about rice, maize, soybean, potato and wheat were calculated with Mechanism method. The spatial-temporal characteristics of agricultural climatic resources and the influence of climate change on potential productivity for the major crops were analysed. Based on the data of agricultural climatic resources, climatic potential productivity, crops acreage. The related mechanism about trajectory of climate change and climatic potential productivity on agricultural planting structure were analysed. The study will provide scientific guidance and reasonable suggestion for crops using agricultural climatic resources efficiently, adjustment of agricultural planting structure, optimize industry layout and sustainable development of agricultural in Ningxia. The main conclusions in this study are as follows:(1) By analyses of the spatial-temporal characteristics of agricultural climatic resources during 1961 to 2012 in Ningxia, and showed that changes significantly of climatic resources. The results indicated that research area was warm-dry weather, and with increase significantly in average temperature, but decrease volatility in precipitation. The trend of warm-dry weather has been most extreme in southern mountainous area and northern irrigation area. Mainly reflects:The average temperature clearly tended to increase and the warming rate are 0.37℃/10a, higher than that the average value of Northwest and national. The trend of precipitation was not obviously and had a certain decreasing among years, and the decreasing rates are 8.33 mm/10a. The most extreme decreasing trend in southern mountainous area, followed by northern irrigation area, but the middle arid area was not obviously. The mutation of the average temperature was 1990s in Ningxia area and later 8～10 years than the national, the average temperature had a more significant trend since 1990. The precipitation had multiple mutations and had a more obviously mutation in 1986. Analyses of based on the climate tendency rate and climate tendency coefficient, climate changes is warm-dry weather in the future.(2) Influence of climate change on potential productivity for the major crops in Ningxia. Mainly reflects:The potential productivity of thermophilic crops (such as rice, maize and soy) showed that had the different levels of increased, and the thecryophilic crops (such as wheat and potato) showed that had levels of decreased, the value of crops potential productivity increasing from south to north. Climate warming has been good for improve photosynthetic, light and temperature potential productivity, but decrease volatility of precipitation restricted the growth in climatic potential productivity. The precipitation was therefore the key factor which restricted the crop growth and yield formation in Ningxia.(3) Climate factors and its change of crop growth period had closely related with crop potential productivity. Mainly reflects:Thermal conditions had satisfaction with rice and potato than other crops. Water conditions had satisfaction with northern irrigation than middle and southern of Ningxia, the satisfaction of rice and potato than other crops, and other crops had smaller difference. Climatic potential productivity significantly and linearly related to average precipitation of crop growth period, but not to average temperature.(4) The value and its changes of climate factors and climatic potential productivity impacts on agricultural planting structure had the obvious lag. Mainly reflects:Northern irrigation has water resources sufficient for irrigation, the trend of warm-dry weather less effects on climatic potential productivity and agricultural planting structure. The trend of warm-dry weather significantly effects on crop growth and yield formation in middle and southern of Ningxia, its cause the agricultural planting structure changes, and its changes from wheat-based to the drought-tolerant crops of maize, wheat and potato. The acreage of Maize and potato has increasing, wheat decreased slightly, soy has most significant reduction. The trend of warm-dry weather has been improving the thermal conditions in south part of Ningxia, but escalating situation of supply and demand of water and drought disaster risk for agriculture. The acreage of Maize and potato has increasing, but wheat and soy decreased slightly.