A summary of soil improvement methods, please remember!

1. Hazards

1. Definition:

Soil acidification refers to the soil absorptive complex receiving a certain amount of exchangeable hydrogen ions or aluminum ions. The process of leaching alkaline ions from the soil.

2. Harm:

?Soil acidification inhibits root development: Soil acidification can aggravate soil compaction, making it difficult for roots to extend, weak rooting, difficult to slow seedlings, and easy to form old and young Trees, old and stiff seedlings, with poorly developed root systems have reduced absorptive functions, weak growth, and reduced yields. Soil acidification increases the waste of pesticides: Plants in acidified soil have weakened growth, reduced disease resistance, and are easily infected by diseases, so they have to increase the amount of pesticides applied. Soil acidification can lead to: low absorption and utilization rates of most medium and trace elements. Soil acidification leads to serious fertilizer loss and fertilizer utilization rate is less than 30%! Soil acidity not only causes the loss of 70% of nitrogen, but also prevents the absorption of 60-80% of phosphorus and potassium components that easily form insoluble substances. In addition, the acidity leads to weak root growth and low nutrient self-absorption and utilization, which results in a large number of The use of chemical fertilizers results in slow growth of crops, many diseases, low yields, and poor quality, resulting in increased inputs and greatly reduced benefits. Soil acidification can lead to: crop malnutrition and serious nutrient deficiencies, such as apple bitter pox, red spots, root nodules, cluster leaves, mosaics, fruit rust, pear ironheads, spots, chicken paw prints and other deficiencies and viruses. Illnesses occur frequently. The tree has weak resistance to stress and is easily eroded by pathogens. No matter how good the medicine is, the occurrence of the disease cannot be controlled! Poor immunity, weak stress resistance, and disease outbreaks. Due to soil acidification, the soil microecological environment has been changed. Harmful microorganisms in the rhizosphere multiply in acidic conditions, and it is difficult to control these diseases. Soil acidification can lead to: changes in soil beneficial microorganism populations, smaller individual bacterial growth, and reduced growth and reproduction rates. For example, the main microbial groups that decompose organic matter and their proteins include Bacillus, Actinomycetes, Methanogens and related fungi. The number of The virtuous cycle of nutrients leads to reduced agricultural production. In particular, acid rain can reduce the number of ammonifying bacteria and nitrogen-fixing bacteria in the soil, reducing the ammoniation and nitrification capabilities of soil microorganisms, which is greatly detrimental to crops.

2. Solutions

1. Reasonable layout of varieties

Crop varieties should pay more attention to their acid resistance. For example, different varieties of vegetables have different sensitivity to acid. In a highly acidic environment with a pH value of 3.5, the yield of acid-sensitive vegetables such as tomatoes, celery, cowpeas, and cucumbers can decrease by 20%; while the yield of medium-sensitive vegetables such as lettuce, kidney beans, and peppers can decrease by 20%. The yield will drop by 10%-20%; the yield of green peppers, cabbage, cabbage, spinach and carrots with strong acid resistance will also drop by less than 10%. Therefore, acid-tolerant vegetable varieties can be grown on acidic soil. Paddy and dry cropping rotation and intercropping are good measures to improve the buffering capacity of soil against acid deposition and accelerate the ecological recovery of acidified soil. Also

2. Apply lime

Applying lime is an important measure to neutralize soil acidity, control soil acidification and increase soil pH. Different forms of lime have different abilities to neutralize acid. For example, the ability of 0.1kg calcium oxide to neutralize acid is approximately equivalent to 0.179kg calcium carbonate. The amount of lime applied depends on the potential acidity of the soil. Lime and other calcium-containing alkaline substances, such as calcium-magnesium phosphate fertilizer, steelmaking slag, kiln dust potassium, plant ash, etc., can not only neutralize soil acidity, but also supplement a large amount of calcium for vegetables. When the soil is contaminated by sulfur ore or pyrite to form highly acidic soil, flood acid washing can be used first, and then lime can be used to neutralize the acidity. If it is a paddy field that has been flooded for a long time, once it is dehydrated and dried, it will immediately become extremely acidic, with a pH value of between 2 and 3, and no grass will grow. At this time, washing with water and neutralizing it with lime can achieve significant results. The amount of soil used is different for different acidic soils: for plots with a pH value of 5.0 to 5.5, about 130 kilograms per mu should be mixed; for plots with a pH value of 5.5 to 6, about 65 kilograms should be mixed per mu; for plots with a pH value of 6.0 to 6.4 , mixed with about 30 kilograms per acre. After spreading the lime, use a rotary tiller to carefully till the soil to thoroughly mix the lime and soil. However, using lime to improve soil will change the soil's aggregate structure and is not suitable for long-term use.

3. Reasonable fertilization

Applying a large amount of decomposed farmyard manure and other organic fertilizers can not only increase the content of organic matter in the greenhouse soil, but also improve the soil's buffering capacity against acidification and make the soil acidic. Increased base value.

Moreover, organic fertilizers can increase the available nutrients in the soil, improve the soil structure, increase the activity of beneficial soil microorganisms, and inhibit the occurrence of crop diseases. Therefore, we should vigorously promote farmyard manure, organic fertilizer, organic-inorganic compound fertilizer and organic activated nutrition package Jiamei Dividend, Hailibao, Yinglilai, etc. to coordinate nutrients and inhibit the acidification tendency of the soil.

4. Apply acid soil conditioners

Studies have shown that soil conditioners such as alkali residue, mushroom residue, sludge, peat, etc. can increase soil pH and reduce acidic soil exchangeability. Aluminum content increases the content of soil organic matter, available nitrogen, available phosphorus, available potassium, exchangeable calcium, and exchangeable magnesium. The application of "Jiamei Dividend Soil Conditioner" can well condition acidic soil, supplement activated organic matter, calcium, magnesium, iron, boron and other elements, and avoid the imbalance of nutritional elements caused by the decrease in soil acidity.

2. Increased salinization

Harm of salinization

1. Definition

Soil salinization (soilsalinization) refers to The salt content in the bottom layer of soil or groundwater rises to the surface with capillary water. After the water evaporates, the salt content accumulates in the surface soil. It refers to the phenomenon or process of accumulation of soluble salts on the soil surface, also known as salinization.

2. Harm of salinization

Soil salinization refers to the increase of salt ions in the soil after long-term excessive application of chemical fertilizers, which prevents the normal water absorption of vegetable roots, thereby affecting plant growth and seriously affecting plant growth. At that time, the crops were like being planted in salt water, resulting in pickled roots and dead trees. Soil salt damage can vary in severity. In the early stage, there will be clear frost on the ground, which then develops into green-skinned "moss", and the crops are still normal; in moderate cases, many lumps of red gelatin will appear on the ground, which will turn into "red frost" after drying. In the middle stage of crop growth, spots of wilting will appear; when the soil salt is too heavy, white crystal "salt frost" will appear on the ground. After the crops are planted, there will be very few root systems, and the dead seedlings will become more serious in the later stage. If the growth is short and the quality becomes poor, for example, cucumbers are not as fragrant and crisp as before, and tomatoes lack the sweet and sour taste, we can conclude that the soil in the greenhouse has been harmed by mild salinization. If the leaves are dry, there are only flowers but no fruit, and there is no harvest, this indicates that severe salt damage has occurred in the greenhouse soil.

Solutions

1. Apply more organic fertilizer

Apply more Rotten farmyard manure.

2. Physical improvement

Level the land, plow deeply and dry the soil, loosen the soil in time, raise the terrain, and improve the soil in micro areas. ?

3. Water conservancy improvement

Irrigation and drainage facilities, fresh water storage and salt pressing, irrigation and salt washing, and underground salt discharge. For example, a drainage and irrigation system is established based on the characteristics of different natural conditions and terrain locations in various places. Irrigation causes the salt in the soil to dissolve in the water. Through penetration into the soil, the soluble saline-alkali in the topsoil is washed out from top to bottom, and then through drainage ditch exclusion.

4. Plant salt-tolerant crops

The amount of water intercepted by trees is 10-100 times that of crops or grass. Planting trees in salinized soil can prevent wind and sand, lower groundwater levels, regulate microclimate, inhibit the rise of salt content, and reduce drought and flood disasters, which has a good management and improvement effect. For afforestation in saline land, forest species with strong salt-alkali resistance should be selected. Arbor tree species include willow, weeping willow, locust, arborvitae, mulberry, neem, elm, apricot, jujube, etc.; shrub species include wolfberry, acacia, and sandweed. Jujube, sea buckthorn, Populus euphratica, Poplar xiaoyi, holy willow, Qiliu, ash strips, etc. ?

Secondly, salt-alkali tolerant pasture can be planted. According to research, after continuous planting of pasture, the organic matter, available nitrogen, and available phosphorus in the soil mostly increased. According to the management practice in Xinjiang, pasture grasses such as sweetsweet and alfalfa have high biological yields and are effective in treating saline-alkali soil. Salt-tolerant crops that can also be planted include sunflowers, castor beans, cereals, sugar beets, corn, cotton, sorghum, barley, etc. At the same time, through genetic breeding, new varieties of rice, wheat and other food crops with strong salt resistance are constantly emerging.

5. Soil treatment

Deep plowing, mixing of sand and soil, and soil replacement.

6. Chemical improvement

Chemical improvement mainly involves applying amendments such as gypsum, phosphoric acid, slag, and polyacrylate solution to the saline soil, and using alkaline water to irrigate the saline-alkali soil. Chemicalize the soil and reduce the salt-alkali content in the soil.

Some developed countries such as the United States and Australia apply chemical amendments on saline soil, especially alkaline soil, such as gypsum, sulfuric acid, and slag (phosphogypsum). Due to different land types, the application amount is also different, and the application time depends on local experience and funding status. After applying the amendment, a large amount of water is needed to rinse, which is difficult to apply when water resources are scarce and the cost is high.