CN111149460B - A method for improving desertified land by combining biochemical materials with commercial crops - Google Patents

Abstract

The invention discloses a method for improving desertification land by combining biochemical materials with cash crop planting, which comprises the following steps of (1) preparing biochemical land improving materials: uniformly mixing the mixed soil, the modified cellulose, the plant straw powder and the decomposed animal manure to obtain a desertification land improvement material; (2) planting of commercial crops: firstly, fertilizer is scattered on the surface of the desertification land, then the prepared desertification land improvement material is paved on the ground, and the seeds of the economic crops are sown and irrigated after rotary tillage by a rotary cultivator, so that the soil is kept moist to ensure the germination, seedling emergence and growth of the seeds. After the invention is implemented in Lanzhou, spring, Zhangye, Dunhuang, Xinjiang Hami and other places in Gansu province, the invention can effectively prevent the water and fertilizer from leaking, obviously reduce the watering and fertilizing times and dosage, improve the utilization rate of the water and fertilizer by 25 to 52 percent, obviously increase the organic matters and the species and the quantity of microorganisms in the soil and obviously improve the ecological function of the soil.

Description

A method for improving desertified land by combining biochemical materials with commercial crop cultivation

technical field

The invention relates to a method for improving desertified land, in particular to a method for improving desertified land by combining biochemical materials with commercial crop planting, belonging to the fields of soil and water conservation and agricultural planting.

Background technique

Desertification is defined by the "Convention on Desertification" (UNCCD): Land degradation in fragile environments (arid, semi-arid and dry sub-humid areas) mainly due to excessive human activities and climate change. The cause of soil erosion degradation is the interaction between the drag of fluids (eg wind or water) and the shear resistance between soil particles. And soil erosion caused by water erosion is the largest source of global soil erosion. Desertification is the most serious environmental and socio-economic problem in the world, which mainly threatens the sustainable development of agriculture and economy. Among them, desertification is the main type of desertification, so the prevention and control of land desertification is the top priority. In the process of desertification control, three main control methods of biology, engineering and chemistry have gradually formed. However, the use of engineering methods has many limitations in terms of cost, timeliness and construction, while the chemical method using polymer materials has the advantages of simple construction, low cost, and quick results. Therefore, the combination of chemical and biological means can not only rapidly improve desertified land, but also create good soil and water conditions for plant growth.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a method for improving desertified land by combining biochemical materials with commercial crop planting, which can effectively prevent water and fertilizer leakage, improve land water and fertilizer utilization, soil organic matter, and microbial species and quantity, thereby improving soil ecological function. .

(1) Preparation of biochemical land improvement materials

Mix the mixed soil, modified cellulose, plant straw powder, and decomposed animal manure evenly to obtain the desertification land improvement material.

The preparation of modified cellulose is obtained by reacting cellulose and compounds containing multiple hydrophilic groups at 70-140 ° C for 2.5-12 times under the catalysis of concentrated sulfuric acid; wherein, the cellulose is sodium carboxymethyl cellulose , at least one of sodium hydroxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxypropyl methyl cellulose, methyl cellulose and ethyl cellulose; compounds containing multiple hydrophilic groups It is a polyhydroxy compound (such as ethylene glycol, glycerol, polyethylene glycol) or a polycarboxy compound (oxalic acid, citric acid, malic acid, humic acid, amino acid), and cellulose and compounds containing multiple hydrophilic groups The molar ratio of cellulose is in the range of 1:1~1:8; the amount of concentrated sulfuric acid is 2~10% of the mass of cellulose.

The reaction equation of cellulose and polyhydroxy compound is as follows:

The reaction equation between cellulose and polycarboxylate is as follows:

As a natural polymer material, cellulose reacts with compounds containing multiple hydrophilic groups, and the resulting modified cellulose has a strong cohesive effect, which can not only prevent soil erosion, but also better inhibit soil moisture evaporation. And it has the functions of water retention, fertilizer retention, and yield increase. The dosage of modified cellulose was 0.05-2 wt% of the mass of the mixed soil. In addition, cellulose has the advantages of a wide range of sources, renewable, biodegradable, non-toxic and harmless, which avoids secondary pollution to the soil.

The mixed soil is a mixture of clay (latterite, montmorillonite, kaolin, attapulgite clay) and loess, and the mass ratio of clay to loess is 1:1~1:5. The role of the mixed soil is to increase the trace elements and minerals required for the growth of various plants in the sandy land.

The main function of plant straw powder is to introduce microorganisms and promote the reproduction of microorganisms. The plant straw is one of wheat straw, corn straw, cotton straw and sorghum straw, and the amount of plant straw powder is 3-15 wt% of the mass of the mixed soil.

Animal manure decomposes quickly after being decomposed under the high temperature anaerobic environment of 60~70℃, which is conducive to the absorption of plants. At the same time, most of the eggs of pests and weed seeds will die. The main effect of decomposed animal manure is to increase the content of soil organic matter and N and P elements. The amount of decomposed animal manure was 5-25 wt% of the mass of the mixed soil.

Mixed soil, plant straw powder and decomposed animal manure can not only reduce the production cost of sand improvement materials, but also provide necessary nutrients for plant growth.

(2) Planting of cash crops

First sprinkle fertilizer on the surface of the desertified land, then spread the above-prepared desertification land improvement materials on the ground, and then use the rotary tiller to sow the seeds of commercial crops, irrigate, and keep the soil moist to ensure the seeds germinate, emerge and grow. , and use potassium humate at different times according to different plant species. Potassium humate has the advantages of reducing crop transpiration, promoting root development, and improving crop drought and disease resistance.

The commercial crops may be at least one of legume nitrogen-fixing plants, non-legume nitrogen-fixing plants, shell grains and vegetable crops. The sowing of crops can be broadcast, planted, or drilled at a distance of 40-60 cm. After the seeds germinate and emerge, according to the specific weather conditions and the needs of the growing season, water 30-200 mm as appropriate.

After the desertification land improvement material prepared by the invention is implemented in Lanzhou, Jiuquan, Zhangye, Dunhuang, Hami, Xinjiang and other places in Gansu, the leakage of water and fertilizer can be effectively prevented, the effect of holding water and fertilizer is remarkable, the frequency and dosage of watering and fertilizing are obviously reduced, and the utilization of water and fertilizer The soil organic matter and microbial species and quantity increased significantly, and the soil ecological function was significantly improved. At the same time, the crop transpiration decreased, the root system became longer, and the disease resistance was improved, and the plants got a better growth environment. While improving desertified land, it drives local economic development.

Detailed ways

The method for improving desertified land of the present invention will be further described below through specific examples.

Example 1. Improvement of desertified land by modified cellulose and leguminous nitrogen-fixing plants

(1) Under the catalysis of concentrated sulfuric acid, sodium carboxymethyl cellulose and glycerol were reacted at 140 °C for 12 h at a molar ratio of 1:3 to obtain hydroxylated sodium carboxymethyl cellulose; Cellulose sodium (0.5 wt% of the mixed soil) and mixed soil (the mass ratio of laterite to loess is 1:2), wheat straw powder (5 wt% of the mixed soil), sheep decomposed under the high temperature anaerobic environment of 70 ℃ The manure (mixed soil 10 wt%) is mixed and mixed to obtain the desertification land improvement material;

(2) Sprinkle 12kg/mu of phosphoric acid diamine on the surface of the land to be improved, and then spread the desertification land improvement materials on the ground, and use a rotary tiller. Sow the seeds of leguminous plants on the ground after rotary tillage, irrigate to keep the soil moist to ensure the germination, emergence and growth of the seeds, and spray the mixture of potassium fulvic acid and carbendazim during the fruit growth period to prevent leaf spot disease happened. After the seeds germinate and emerge, they are cut and buried at the early flowering stage, and watered as appropriate according to specific weather conditions and growing seasons.

One year after the method was implemented in Zhangye, Gansu, the effect of preventing water and fertilizer leakage and retaining water and fertilizer was remarkable, the incidence of leaf spot disease was significantly reduced, and the effect was better than that of using carbendazim alone, and the effective utilization rate of water and fertilizer was increased by more than 43%. ; After 2 years, soil organic matter, microbial quantity and species increased significantly. See Table 1 for details:

Example 2. Improvement of desertified land by modified cellulose and non-legume nitrogen-fixing plants

(1) Under the catalysis of concentrated sulfuric acid, sodium hydroxymethyl cellulose and oxalic acid were reacted at a molar ratio of 1:5 at 110 ° C for 2.5 h to obtain sodium carboxymethyl cellulose; Plain sodium (0.8 wt% of mixed soil) and mixed soil (mass ratio of attapulgite to loess is 1:2), corn stalk powder (8 wt% of mixed soil), pigs decomposed under high temperature anaerobic environment at 65 ℃ The dung (18 wt% of the mixed soil) is mixed, and stirred and mixed to obtain the desertification land improvement material;

(2) Put the rhizobia agent in the tree hole of 1.5 m×1.5 m, sprinkle 10 kg/mu, sprinkle diamine phosphate in the tree hole, spread the desertification land improvement material in the tree hole, and plant alder And sea buckthorn seedlings, bury the soil, irrigate, keep the soil moist to ensure that the seedlings take root and grow, and spray 1200 times potassium fulvic acid solution during the wintering period of the plants. After the saplings are planted, they need to be watered as appropriate according to the specific weather conditions and growing season.

One year after the method was implemented in Hami area of Xinjiang, the effect of preventing water and fertilizer leakage, retaining water and fertilizer is remarkable, leaf senescence is delayed, the number of green leaves is maintained, and the effective utilization rate of water and fertilizer is increased by about 40%; after 2 years, soil organic matter, microbial quantity , the species increased significantly. Alder grows rapidly and has excellent sand-fixing and soil-preserving effects. See Table 2 for details:

Example 3. Improvement of desertified land by modified cellulose and shell grains

(1) Under the catalysis of concentrated sulfuric acid, hydroxypropyl cellulose and polyethylene glycol were reacted at a molar ratio of 1:2 at 140 °C for 4 h to obtain hydroxylated hydroxypropyl cellulose; plain (1.5 wt% of the mixed soil), mixed soil (the mass ratio of montmorillonite and loess is 1:2), plant straw powder (12 wt% of the mixed soil), cattle decomposed under the high temperature anaerobic environment of 60 ℃ The manure (25 wt% of the mixed soil) is mixed, stirred and mixed to obtain the desertification land improvement material;

(2) Sprinkle 15 kg of urea and diamine phosphate on the surface of the land, spread the desertification land improvement materials on the ground, and use a rotary tiller. The seeds of shell grains were dressed with 0.5% potassium fulvic acid, drilled on the ground after rotary tillage at a distance of 50 cm, and irrigated to keep the soil moist to ensure the germination, emergence and growth of the seeds. After the seeds germinate and emerge, they need to be watered as appropriate according to specific weather conditions and growing seasons.

After the method was implemented in Dunhuang area of Gansu for one year, the effect of preventing the leakage of water and fertilizer, retaining water and fertilizer is remarkable, the average root length is obviously increased, and the effective utilization rate of water and fertilizer is increased by about 32%; after 2 years, the soil organic matter, the number and species of microorganisms are remarkable Increase. While improving desertified land, it drives local economic development. See Table 3 for details:

Example 4. Improvement of desertified land by modified cellulose and vegetable crops

(1) Under the catalysis of concentrated sulfuric acid, the molar ratio of hydroxyethyl cellulose and amino acid 1:4 was reacted at 70 °C for 3 h to obtain modified hydroxyethyl cellulose; then modified hydroxyethyl cellulose (mixed soil 1.2 wt%) and mixed soil (the mass ratio of kaolin to loess is 1:2), corn stover powder (mixed soil 12 wt%), and horse manure (mixed soil 25 wt%) decomposed in a high-temperature anaerobic environment at 70 °C ), and stir and mix to obtain the desertification land improvement material.

(2) Sprinkle 20 kg of Yangfeng compound fertilizer on the surface of the land, spread the desertification land improvement materials on the ground, and use a rotary tiller. Dress the seeds of vegetable crops with 0.5% potassium fulvic acid, drill and sown at a distance of 40 cm on the ground after rotary tillage, and irrigate to keep the soil moist to ensure the germination, emergence and growth of the seeds. Once every 15 days, spray 3 times of 1500 times potassium humate solution continuously. After the seeds germinate and emerge, they need to be watered as appropriate according to specific weather conditions and growing seasons.

One year after the method was implemented in the Dunhuang area of Gansu, the effect of preventing water and fertilizer leakage, retaining water and fertilizer is remarkable, crop transpiration is significantly reduced, and the effective utilization rate of water and fertilizer is increased by about 27%; after 2 years, soil organic matter, microbial quantity and species are significantly Increase. While improving desertified land, it drives local economic development. See Table 4 for details:

Claims (4)

1. A method for improving desertified land by combining biochemical materials with commercial crop cultivation, including the following: (1) Preparation of biochemical land improvement materials: Mix the mixed soil, modified cellulose, plant straw powder, and decomposed animal manure evenly to obtain desertification land improvement materials; The mixed soil is a mixture of clay and loess, wherein the clay is laterite, montmorillonite, kaolin, and attapulgite clay, and the mass ratio of clay to loess is 1:1~1:5; The preparation of modified cellulose is obtained by reacting cellulose with a compound containing multiple hydrophilic groups at a molar ratio of 1:1 to 1:8 at 70 to 140 ° C for 2.5 to 12 hours under the catalysis of concentrated sulfuric acid; , cellulose is at least one of sodium carboxymethyl cellulose, sodium hydroxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxypropyl methyl cellulose, methyl cellulose and ethyl cellulose One; the compound containing multiple hydrophilic groups is a polyvalent hydroxyl compound or a polyvalent carboxyl compound; The dosage of modified cellulose is 0.05-2 wt% of the mixed soil mass; the dosage of decomposed animal manure is 5-25 wt% of the mixed soil mass; the dosage of plant straw powder is 3-15 wt% of the mixed soil mass; (2) Planting of commercial crops: first sprinkle fertilizer on the surface of desertified land, then spread the above-prepared desertification land improvement materials on the ground, and then use rotary tiller to sow the seeds of commercial crops and irrigate to keep the soil moist To ensure seed germination, emergence and growth, and use potassium fulvic acid in different periods according to different plant species; the economic crops are at least one of legume nitrogen-fixing plants, non-legume nitrogen-fixing plants, shell grains and vegetable crops. 2 . The method for improving desertified land by combining biochemical materials with commercial crop planting according to claim 1 , wherein the plant straw is one of wheat straw, corn straw, cotton straw, and sorghum straw. 3 . 3. The method for improving desertified land by utilizing biochemical materials in combination with commercial crop planting according to claim 1, wherein the animal excrement is the excrement after being decomposed under the high temperature anaerobic environment of 60-70°C. 4. as claimed in claim 1, utilize biochemical material and commercial crop planting to combine the method for improving desertification land, it is characterized in that: the sowing of crop is sowing, planting or drilling by the distance of 40～60 cm; , According to the specific weather conditions and the needs of the growing season, water 30~200 mm as appropriate.