The function and usage of humic acid fertilizer

Humic acid fertilizer refers to the use of peat, lignite and weathered coal to produce products containing a large amount of humic acid and nitrogen, phosphorus, potassium and some trace elements needed for crop growth and development. The role in agricultural production is mainly to stimulate crop growth, improve soil, increase nutrients, strengthen soil microbial activities, and so on. Let's take a look at the role and usage of humic acid fertilizer.

Varieties of humic acid fertilizers

1. According to the source, humic acid fertilizer can be divided into two categories: natural humic acid and artificial humic acid. In natural humic acid, it can be divided into soil humic acid (white), coal and coal humic acid, water humic acid and mold humic acid.

2. Humic acid fertilizer can be divided into primary humic acid and regenerated humic acid (including humic acid in naturally weathered coal and artificially oxidized coal).

3. Humic acid fertilizers can be classified into fulvic acid, brown humic acid and black humic acid according to their solubility and color in solvents. In the previous literature, there are also the names of gray humic acid, brown humic acid and green humic acid, which are actually separated from different solvents.

4. According to the natural binding state, humic acid fertilizer is divided into free humic acid and (calcium, magnesium) bound humic acid.

5. According to the humic degree of humic acid, humic acid fertilizer can be divided into A type, B type (real humic acid), RP type and P type (immature humic acid) and so on.

The function of humic acid fertilizer

1, can improve nitrogen use efficiency: nitrogen fertilizer is an indispensable fertilizer for plant growth, mainly urea and carbamines, when urea and carbamines are applied to the ground, they will soon be lost with air and water, and only 30% of nitrogen nutrients can be really absorbed and utilized by crops. The acidic functional groups such as aromatic nuclei, hydroxyl groups and carboxyl groups in humic acid can react with nitrogen elements to form stable new ion groups. these complexes remain in the soil for a long time and gradually decompose and release nitrogen elements. let the plant absorb slowly.

2. It has synergistic effect on phosphate fertilizer: after the available phosphorus fertilizer is applied to the soil, the phosphorus element will be fixed by the metal ions in the soil, so that the available phosphorus will be transformed into late available phosphorus or ineffective phosphorus. The acidic functional groups such as aromatic nuclei, hydroxyl groups and carboxyl groups in humic acid react with phosphorus elements to make them soluble phosphorus, which increases the activity of phosphorus elements and is easily absorbed by plants. According to statistics, after the application of humic acid fertilizer, the fertilizer efficiency of phosphate fertilizer can be relatively increased by 5%.

3. It has a synergistic effect on potash fertilizer: the functional groups in humic acid can also absorb and store potassium ions, which can not only prevent potassium ions from losing with water in sandy soil, but also prevent the fixation of potassium in clayey soil, and can increase the utilization rate of potassium fertilizer by about 5%.

4. It has the function of water and fertilizer conservation: humic acid interacts with calcium ions in the soil to form flocculent gel, which can cement the soil together, turn the soil particles into a small reservoir and fertilizer reservoir for water and fertilizer conservation, and increase the soil voidage. as a result, the ability of soil water and fertilizer conservation is improved.

Usage of humic acid fertilizer

1. Seed soaking: seed soaking can improve seed germination rate, early emergence and enhance the ability of seedling rooting. Generally, the concentration of seed soaking is 0.005 / 0.05%, the time of seed soaking is 5 / 10 hours, and the hard-shell seeds such as rice and cotton are 24 hours.

2. Soaking roots: Rice, sweet potato and so on can soak seedlings with humic acid sodium or potassium humate solution before transplanting, and the concentration is 0.01-0.05%. After soaking seeds, the roots were fast and the survival rate was high.

3. Spraying: the general concentration is 0. 01-0. 05% solution, spraying 2-0. 3 times in the flowering period of crops, each time spraying 50 liters of water solution per mu, the spraying time should be 2-4 pm and the effect is good.

4. Base fertilizer: solid humic acid fertilizer (such as ammonium humate, etc.), generally 100-150 kg per 6 mu. When humic acid solution is used as base fertilizer, the concentration is 0.05-0.1%, 250-400 liters of water solution per 6 mu, which can be mixed with farm fertilizer, ditch application or hole application.

5. Topdressing: about 250 liters of 0.01-0.1% aqueous solution per 6 mu is irrigated near the crop root system before the seedling stage and heading stage. Paddy field can be applied with irrigation or sprinkled on the water surface, which can play the role of raising seedlings, strengthening seedlings, promoting growth and development and so on.