Planted year after year, the salinity is high, what should I do if the salt damage?

Continuous planting and fertilization will increase the salinity and cause soil compaction, affecting plant growth and intake of inorganic matter and water.

Treatment method: microbial treatment method: apply microbial fertilizer to the soil, the secretion of microorganisms can dissolve the phosphate in the soil, release phosphorus, and at the same time, release potassium and trace element cations, restore the aggregate structure in the form of bond bridges, and eliminate soil compaction.

Organic fertilizer conditioning method: increase the application of organic fertilizer. Increasing the application of organic fertilizer, such as pig and cattle pen fertilizer, can not only improve the soil structure, enhance the performance of soil fertilizer retention, air permeability and temperature regulation, but also improve the content of soil organic matter, enhance the soil fertilizer storage performance and buffering capacity of acid and alkali, and prevent soil compaction.

Straw returning to the field: crop straw is the original source of organic fertilizer, straw crushing and returning to the field can improve the content of soil organic matter, increase soil porosity, coordinate the water, fertilizer, gas and heat in the soil, create a good environment for soil microbial activities, is conducive to the decomposition and softening of organic matter, and improves the physical and chemical properties of soil.

For continuous planting, you can use deep ploughing of the soil, ridge formation, and more well-rotted organic fertilizer. Of course, this is only the premise. In the later stage, it can be diluted with water to reduce the threat of salt, plus physiological foliar spraying of plant salt resistance + foliar spraying of snow green abundant water-soluble fertilizer.

Improves the activity of crop enzymes. At the same time, the crops will grow strong in the province.

Excessive soluble salt chains in the soil under osmotic stress reduce the soil water potential, resulting in difficulty in plant water absorption, and in severe cases, it may even cause water extravasation in plant tissues, resulting in physiological drought, and obstructing normal physiological processes such as growth and photosynthesis.

Ion imbalance: Too many ions of one type in the soil often exclude the absorption of other ions by plants. For example, wheat grows in an environment with too much Na, and its body lacks K, and the absorption of Ca2 and Mg2 is also blocked. Too much phosphate can lead to zinc deficiency.

The decrease of photosynthesis and the decrease of the activities of PEP carboxylase and RUBP carboxylase due to excessive salinity, the decrease of chlorophyll and carotenoid content, the decrease of stomatal opening, and the increase of stomatal resistance led to a significant decrease in the photosynthetic rate of stressed plants.

The effect of unstable respiration and excessive salt on respiration is related to the concentration of salt, with low salt promoting respiration and high salt inhibiting respiration. For example, the respiration of alfalfa in 5g·L1NaCl nutrient solution was 40 higher than that of the control, and the respiration in 12g·L1NaCl was 10 lower than that of the control.

Protein synthesis is hindered, and many plant protein synthesis is hindered by excessive salts, and the degradation process is accelerated. On the one hand, salt stress forces nucleic acid decomposition to be greater than synthesis, thereby inhibiting protein synthesis, and at the same time, amino acid biosynthesis is hindered under high salt conditions.

Toxic substance accumulation salt stress forces the accumulation of toxic substances in plants, such as a large number of nitrogen metabolism intermediates (such as NH3, putrescine, cadaverine, etc.).

1) The soil pH is high, the salinity is strong, and there are many toxic salts. In some saline-alkali soils, there are as many as 12 kinds of salt, 7 of which have different degrees of harm to crops. These salts have different solubility in soil solutions, and the water-soluble salts formed by them are harmless to rice if the rhizosphere content does not exceed a few parts per 10,000 to a few parts per 100,000, and is the nutrient required by rice.

However, when its concentration exceeds the limit of salt tolerance in rice, it can be harmful. Among them, the most toxic is soda, which is generally toxic when the content is exceeded. Soda is more alkaline, pH up to 8 10, soluble salt more, hindering rice plants to absorb water, heavy can form reverse osmosis to make water flow back, resulting in physiological water shortage, wilting phenomenon.

The sodium carbonate and sodium bicarbonate in soda alkaline soil are sometimes converted into sodium hydroxide, which reduces the availability of soil nutrients, making rice unable to absorb and more harmful. Strong alkalinity can also directly harm rice plants, corrode and damage cell tissues, and die in severe cases.

2) High substitution sodium content. The alkalinity (the percentage of soil substitution sodium in cation exchange) in the 1-meter soil layer was mostly between 10% and 60%. The higher the degree of alkalinization, the more calciums become ineffective.

Rice does not absorb enough calcium, but on the contrary, absorbing too much sodium will harm the rice plant. Sodium is a strong dispersant, which can make the soil highly dispersed under the flooding conditions of the mold roller, and the permeability deteriorates, hindering the normal growth and development of the root system. Therefore, it is an important factor for high rice yield to reduce the alkalinity to less than 10% and improve the physical properties of soda saline-alkali paddy soil.

3) The soil is prone to waterlogging. Most of the saline-alkali areas are in depressions, so the drainage is not smooth, and it is easy to produce waterlogging. Waterlogging comes in two forms:

First, the surface runoff from the highlands is concentrated in the low-lying land, causing surface waterlogging; The second is soil waterlogging caused by high groundwater levels. Therefore, not only the soil temperature decreases, but also the saline-alkali hazard is aggravated. The most obvious symptoms of salinity and waterlogging are that the cells of the new roots and root growth points are first damaged, and then spread to the whole root, so that the root system loses its vitality, the plant grows slowly, the leaf tip withers yellow and curls, the basal leaf dies, and finally the heart leaf dies.

Use more organic fertilizer, fungus fertilizer, and farmhouse fertilizer must be rotten.

In recent years, the problem of soil salt damage has become more and more prominent in the cultivation of greenhouse vegetables.

The total salinity of greenhouse soil is getting higher and higher, and many of them have exceeded the content range suitable for vegetable growth, and the occurrence of vegetable physiological problems is becoming more and more frequent.

So, how is the soil salt damage caused? What are the characteristics of soil salinity? Let's take a look.

How is soil salinity caused by human factors Unreasonable fertilization methods: excessive application of chemical fertilizers; Partial fertilizer, only or first nitrogen fertilizer, no organic matter and medium and trace element fertilizer; Long-term non-supplementation of beneficial microorganisms.

Inferior manure application: such as chicken manure mixed with caustic soda, will destroy the soil pH, cause direct damage to the root system, and make the crop unable to grow normally.

Long-term use of flood irrigation irrigation method, poor drainage, clay soil, impermeable soil wheel family.

Long-term greenhouse planting and film covering, lack of rainwater washing, resulting in excessive salt accumulation.

Climatic factorsA dry climate can exacerbate the evaporation of soil moisture, resulting in an excessive concentration of soil salt, resulting in salinization.

Soil freezing exacerbates the process of soil salinization.

Topographic and geomorphological factorsNatural saline soils are mostly found in coastal saline soils, coastal lowlands and other soils affected by seawater inundation and backfilling, or in arid inland basins.

What are the characteristics of soil salt damage: plant growth is sluggish or stopped, leaf color becomes thick, ossified, wilted and yellowed in severe cases; Root growth is stunted.

The symptoms of damage vary from vegetable to vegetable.

Fruit trees: The survival rate of fruit trees on saline-alkali land is very low, and fruit trees damaged by salt often show achlorosis and develop lobular disease.

Salt damage had an inhibitory effect on flower bud differentiation and the growth of roots, branches, leaves and fruits.

The young organs have a top wilt, and in severe cases, it can cause dead trees or dead roots.