Three evils of lankao

The three evils of Lankao refer to waterlogging, sandstorm and salinity.

Lankao county is located in the northeast of Henan Province, bordering Xiangfu District of Kaifeng City in the west, Minquan County of Shangqiu City in the east, Dongming County and Cao Xian County of Heze City in the north and Qixian County of Kaifeng City in the south. Famous scenic spots include Jiaoyoulu Memorial Park, Yellow River Bay Scenic Area and Traffic Square.

Waterlogging is rainy weather. Because the rivers and ditches are impassable, the accumulated water can't be discharged from the fields, and crops can't grow normally after being soaked in water for a long time. Sandstorm, that is, after undrained land is exposed to the sun, the soil loses moisture and becomes fine sand, and the atmosphere blows over the dust all over the sky, just like the current sandstorm.

Sandstorm refers to the sand raised by hurricane or the wind mixed with sand. It also refers to the natural phenomenon that strong winds blow up a lot of dust on the ground and drag it into the air, making the air particularly turbid. Wind-blown sand action refers to the action of wind-blown sand on the surface. The process in which sand particles are blown off the ground by the wind, carried by the airflow in the form of suspension, jumping and peristalsis, and then piled up on the ground.

Saline-alkali land is a kind of salt accumulation, which means that the salt contained in the soil affects the normal growth of crops. Saline soil, especially the surface layer (0 ~ 20cm) contains a lot of soluble salts (above 0.6 ~ 2%). Generally, it is formed under the influence of natural conditions such as dry climate, little rain, large evaporation, low terrain, high groundwater level and high salinity and human activities.