What are the regions of rice production in Guangdong? What are the characteristics of each?

Guangdong Province is bordered by the Nanling Mountains in the north and the South China Sea in the south. Rice is grown in vast areas ranging from tidal fields at flat sea level to mountain terraces thousands of meters above sea level. Guangdong has a monsoon subtropical and tropical climate. The safe growth period of rice is 220-280 days in most places. The rice cropping season is long, such as early rice in Guangzhou, sowing in early March and harvesting in mid-July; typical late rice varieties are sown in late June, heading around October 10, and harvested in mid-November. Abundant rainfall and long sunshine hours are all beneficial to the growth of rice. However, there are many disastrous weather in Guangdong Province, mainly: "four winds", that is, typhoon, cold dew wind, Qingming wind, dry and hot wind; "three waters", that is, dragon boat water (mango water), the Autumn Equinox water, low temperature and overcast rain in early spring; and "second drought", that is, spring drought and autumn drought. In addition, there are rice blast, bacterial blight, sheath blight, rice stem borer, rice planthopper, rice leaf roller and so on. Typhoon and cold dew wind are especially harmful in natural disasters. The area of rice in Guangdong Province is large, and the planting system of rice field is mainly double-cropping rice. The rice cropping area of Guangdong Province can be divided into four rice cropping areas.

(1) Rice growing area in northern Guangdong. It is located in the northern mountain area north of Shakou in Yingde County. It is divided into two subregions: the northwest single cropping rice sub-region and the northern Guangdong double cropping rice sub-region. The rice fields are sparse, the altitude is high, the proportion of low-yield fields is large, and the water conservancy conditions are poor. It belongs to the area of heavy rice blast in Guangdong Province. The area of rice in this rice planting area is small, the safe growth period of rice is short, and it is cold in autumn, so it belongs to the heavy Cold Dew wind area. Typhoon damage is very small, less annual sunshine hours, more spring rain, easy drought in autumn, the original per unit yield is lower. The early rice is mainly medium-maturing varieties, and the early-maturing temperature-sensitive hybrid rice is the majority of late rice. Double-cropping rice is generally planted except for single-cropping rice in some parts of the northwest. The rice planting season is short, the spring sowing is late, the autumn harvest is early, and the summer harvest and summer planting are very tight.

(2) Middle-north rice growing area. Located in the north-central hilly area south of Shakou in Yingde County to the north of Guangzhou, the southern boundary roughly passes near the Tropic of Cancer. It can be divided into three subregions: Hanjiang Hilly Sub-region, Dongjiang Beijiang Hilly Sub-region and Xijiang Hilly Sub-region. The distribution of paddy fields is sparse, the water conservancy conditions are good, and about 69% of paddy fields are harvested by drought and waterlogging. The lower reaches of Beijiang River and Xijiang River are vulnerable to flood. Hanjiang River and Beijiang River often invade paddy fields because of heavy soil erosion. It belongs to the serious rice blast and bacterial leaf blight disease area in Guangdong Province. In this rice cropping area, the rice area is large, the total yield is high, and the level of per unit yield is medium. The safe growth period of rice in this rice cropping area is shorter and the autumn is cold earlier, which belongs to the heavy Cold Dew wind area in Guangdong Province. Double-cropping rice is the main crop, and one-cropping rice is planted in low-lying fields and pond fields. The varieties of early and late rice are mainly mid-mature. The rice planting season is shorter, the spring sowing is later, the autumn harvest is earlier, and the summer harvest and summer planting is tight.

(3) Rice cropping area in central and southern China. It is located in the south-central coastal plain and hilly area south of Guangzhou. It is divided into five subregions: Chaoshan Plain Subregion, Southeast Coastal Hilly Subregion, Pearl River Delta Subregion, Southwest Coastal Hilly Subregion and Jianjiang Hilly Subregion. The area of paddy fields accounts for about 46% of the province. The rice field in this rice growing area is dense, with an elevation of 1 to 30 meters above sea level. With good or good water conservancy conditions, large rice area, high per unit yield and high total yield, it is the most important rice producing area in Guangdong Province. This rice-growing area is a serious disease area of bacterial blight in Guangdong Province. Double-cropping rice is the main type, early rice varieties are mainly late-maturing type, and most late rice varieties are early-maturing temperature-sensitive hybrid rice or conventional early rice turning autumn. The spring sowing is earlier, the autumn harvest is late, and the rice cropping season is longer. In addition to double cropping, there are multiple cropping of rice and sugar cane, peanuts and sweet potatoes.

(4) Southwest rice cropping area. This rice-growing area is located in Leizhou Peninsula. Due to the serious spring drought and poor water conservancy conditions, the proportion of paddy fields protected by drought and waterlogging is relatively low. The safe growth period of rice is long, with the earliest spring sowing and late autumn harvest. There are many typhoons, which belongs to the heavy typhoon area of Guangdong Province. The number of sunshine in the early season is more than that in the late season, which is one of the significant differences between the early season and other rice growing areas. It is prone to drought in spring and rainy in autumn. It is a serious disease area of bacterial blight. This rice-growing area is mainly double-cropping rice, as well as multiple cropping of rice and peanuts, sweet potatoes, sugarcane and other crops.