Climatic conditions and characteristics of rice growing areas

China's rice region is vast, then you know the climatic conditions of rice growing areas? The following is my carefully organized for you to take a look at the climatic conditions of rice growing areas.

The climatic conditions of rice planting areas

1. Rich heat resources, suitable for the development of a variety of rice cropping system The average temperature of China's rice growing period of 18 ~ 25 ℃; the country's various rice districts, the average temperature of the hottest month is generally more than 20 ℃, and the period of high temperature is consistent with the need for high-temperature rice. Hainan Island rice area & gt; 10 ℃ cumulative temperature of 8000 ℃ or more, the whole year can be planted rice; south of the Yangtze River Basin to South China & gt; 10 ℃ cumulative temperature of 5000 ~ 8000 ℃, can be planted double-season rice; north of the Yangtze River Basin to North China & gt; 10 ℃ cumulative temperature of 4000 ~ 5000 ℃, can be planted in a single season of middle rice; Northeast, Northwest rice area & gt; 10 ℃ cumulative temperature of 2000 ~ 4000 ℃, can plant a season of early rice.

Due to the summer by the subtropical high pressure control as well as the influence of the continent, China's rice area summer temperatures than many areas of the world at the same latitude to be higher, the average temperature in July, Nanjing (32?00?N) for 28.0 ℃; Japan's Kagoshima (31?34?N) for 27.2 ℃; Jinan (36?42?N) for 28.2 ℃; Algiers (36?08?N) for 24.8°C; Qiqihar (47?20?N) is 22.0°C; and Zurich (47?23?N) is 18.4°C. The favorable thermal conditions allow the distribution of rice in China to be further north than in other countries.

2. Superior light energy resources, which is conducive to high rice yields China's Yangtze River, the lower reaches of the Yellow River Basin and the rice growing season the total amount of solar radiation for (256-342)?107J/m2; and Japan at the same latitude for (217-290)?107J/m2, China is about 18% more than Japan, especially in the fall, the rice tasseling and grouting period, most of the rice areas in China with sufficient sunshine! that is very favorable for high rice yield.

3. Light, heat, water in the same season China is affected by the monsoon climate, the rice area of the precipitation is basically concentrated in the summer; and summer is a higher temperature, sunshine stronger season. Therefore, in China's rice area, light, heat, water, three of the most important climatic resources are concentrated in the vast majority of the rice growing season, when China's rice climate is an extremely important advantage, is rice in China has become the most important food crops in the natural background, the world and China's latitude similar to other regions, such as the western and southern United States rice areas, the Middle East, North Africa, etc., the summer precipitation are very little or less, or can not planting rice, or need a larger amount of irrigation. Or need a larger amount of irrigation.

4. rice meteorological disasters more China's rice climatic conditions also have unfavorable side, mainly more frequent meteorological disasters, China because of the back of the Eurasian continent, since the fall to the spring, there will be Siberia to the cold air invasion, so the country's various rice districts will be subject to cold damage. Spike blossoming period is the most sensitive to cold damage to low temperatures in the period, China's Northeast, Northwest rice areas, as well as southern double-season rice areas, spike blossoming cold damage is a threat to rice production.

China's coastal rice areas, in July and September, are threatened to varying degrees by typhoons, which cause rice toppling, grain drop, and sometimes flooding.

China, due to the influence of monsoon climate, the inter-annual variation in the strength of the monsoon, resulting in large inter-annual variations in climate. As a result, droughts and floods are more serious in China's rice areas. Spring drought is heavier in the northern rice areas, which is unfavorable for seedling production. Central China ambient drought is heavier, South China autumn drought is heavier; unfavorable to middle and late rice.

Characteristics of rice-growing areas

(1), smallholder operations. Rice production to the family as a unit, due to the small amount of arable land per capita, each family cultivated fields are very small, the southern part of China, each family cultivated rice area is generally less than 1 hectare;

(2), the unit area of production is high, but the rate of commodities is low. Farmers work intensively in the field, so that the yield per unit area of rice is high. However, due to the small scale of production, the total output of rice per household is not large, subject to traditional attitudes and economic level of constraints, farmers will collect a considerable portion of the rice retained for their own use, and sent to the market to sell a limited number of paddy; but Thailand is a special case, its exports more.

(3), mechanization and low level of science and technology. Farmers are generally engaged in manual labor, although in the past decade or two, the use of electricity for irrigation, threshing and other development faster, fertilizers, pesticides, the gradual increase in the use of fertilizers, pesticides, but in general, the level of mechanization and science and technology is still relatively low; In addition to the Japan in the paddy field mechanization has made greater progress, the level of mechanization of rice production in other Asian countries is still very low.

(4), the water conservancy project is large. Irrigation is the basis of rice production. Monsoon area frequent floods and droughts, the threat to rice production and big. Small farmers can not afford to build water conservancy projects, the need for the government's strong investment and organization of water conservancy projects;

4. In addition to Asia, Africa's Egypt, Nigeria, Europe's Spain, Italy, Latin America's Cuba, Venezuela, Brazil also has the distribution of rice cultivation, in the United States of America's Lower Mississippi River region, also distributed a large number of rice paddies, but the use of a large-scale dryland direct seeding technology for production. For one of the eight agriculture.

Rice cultivation conditions

①, with higher yield potential of super rice varieties

Super rice varieties with high yield, high quality, multi-resistant comprehensive performance, with obvious yield potential, in different latitudes can be achieved respectively 700, 800, 900 kilograms per mu, is the main condition of rice super high yield.

From the analysis of group quality theory to improve the accumulation capacity of photosynthetic production of the group during the fruiting period, super rice should have a high grain/leaf (cm2) ratio, leaf erect, spikes large grains and heavy morphological and structural characteristics, which is conducive to the formation of more total glumes and larger total library capacity under the limited suitable leaf area index (LAI) conditions, and capture the super-high yield. Multi-spike small spike and small grain varieties, grain/leaf (cm2) ratio is low, the total reservoir capacity should not be increased, does not have super rice conditions.

②, with suitable climatic conditions

(1) temperature High-yield rice lifetime need to have suitable atmospheric temperature conditions, especially 15 days before the spike to 25 days after the spike in this 40 days to have suitable temperature conditions, can not appear below 15 ℃ and higher than 35 ℃ hazardous temperature. Observations have consistently shown that the average daily temperature of about 25℃ during the spiking period of japonica rice is most favorable for increasing the fruiting rate, and the average daily temperature of about 21℃ during the period of grouting to maturity has the highest thousand-kernel weight (the daytime temperature is about 26℃, the nighttime temperature is about 16℃, and the difference between daytime and nighttime temperatures is about 10℃). In the northern cold area of rice cultivation in the average annual temperature below 0 ℃, but, during the growth of japonica rice there, especially before and after the spike of more than 40 days with very suitable climatic conditions, the same can appear super-high yield records. For example, the highest yield record of Hongwei Farm in 2005 was 733 kilograms per mu, and the highest yield record of Qixing Farm in 2006 was 830.5 kilograms per mu.

(2) heat radiation Strong heat radiation is another climatic factor of rice super high yield. In high latitude, high altitude areas with high solar heat radiation, rice yield is high, such as Yunnan Yongsheng Taoyuan Township high-yield fields up to 1100-1200 kilograms per mu, Heilongjiang Province, Qixing Farm high-yield rice yield up to 830 kilograms per mu, indicating that the amount of solar radiation and rice yield is closely related.

3) Atmospheric humidity Lower atmospheric humidity is also an important factor in the super high yield of rice. First, low atmospheric humidity is the result of fewer rainy days and less rainfall, which means high daily radiation, which is conducive to increasing the photosynthetic productivity of the population. Secondly, under high temperature and strong light conditions, lower atmospheric humidity increases transpiration, which can significantly reduce the temperature of the rice plant from the harm of high temperatures, ensuring the normalization of photosynthetic production and various physiological activities. Once again, low atmospheric humidity is light on disease, which is conducive to high yield.

⑷ catastrophic weather High-yield areas also require basically no typhoons, tornadoes and other catastrophic and destructive weather disasters.

③, with better soil conditions

(1) soil organic matter and soil nitrogen supply level In the same type of soil, the soil nitrogen supply capacity are manifested with the rise of soil organic matter content, but different soil types can not be used in a unified formula to deduce the relationship between the organic matter and the amount of nitrogen supplied by the soil. That is, different soils with the same organic matter content have different nitrogen supply.

(2) Soil total nitrogen content and soil nitrogen supply level The relationship between soil total nitrogen content and soil nitrogen supply is the same as soil organic matter content and nitrogen supply level.

③ Soil fertility It is also a necessary condition for super-high yield, especially to have a certain base yield (the yield of blank field).

④, with irrigation and drainage conditions that can control soil moisture Ultra-high-yield cultivation field not only to ensure that it can be timely irrigation, but also to ensure that it can be timely drainage, especially in the middle and late stages of reproduction in order to improve the root system vitality, to take the intermittent irrigation, there must be a timely discharge of stagnant water conditions.