Adding crop residues, green leaves and application of compost

Organic matter has higher nutrient retention capacity. It has high surface area which can bind molecules tightly and prevent from leaching or erosion

Dr Pinthujan Priyathashini thank you for your contribution to the discussion

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Nutrients can be replenished in the following ways: Fertilizers and manures contain plant nutrients such as nitrogen, phosphorous and potassium, etc. So, when fertilizers and manures are added to the soil in the fields, then the soil gets enriched with nutrients like nitrogen, phosphorous and potassium, etc. Today, farmers add numerous soil amendments to enhance soil fertility, including inorganic chemical fertilizers and organic sources of nutrients, such as manure or compost, often resulting in surplus quantities of primary macronutrients. Farmers may apply commercial fertilizers, manure, soil amendments, or organic-by-productsto provide the nutrients plants need. The most common method for ensuring proper micronutrient content within the soil is through increasing and enhancing the soil organic matter, which can be seen as a reservoir for holding stable forms of nutrients. In many cases, micronutrients can also be supplied with foliar sprays. Soil organic carbon not only improves soil nutrient bioavailability but also affects soil fertility by various other mechanisms and is of central importance for the global C-cycle, which may strongly affect atmospheric CO2-concentrations. Soil organic matter significantly improves the soil's capacity to store and supply essential nutrients and to retain toxic elements. It allows the soil to cope with changes in soil acidity, and helps soil minerals to decompose faster. Organic matter contributes to nutrient retention and turnover, soil structure, moisture retention and availability, degradation of pollutants, and carbon sequestration. Through the process of photosynthesis, plants assimilate carbon and return some of it to the atmosphere through respiration. The carbon that remains as plant tissue is then consumed by animals or added to the soil as litter when plants die and decompose. Improved soil health: soil carbon sequestration helps restore degraded soils, which can improve agricultural productivity. Increased climate resilience: healthier soils make farms more resilient against both droughts and heavy rainfall.

How do farmers maintain the nutrient ratio in the soil and the role of soil organic matter in soil fertility and carbon storage?

It depends on what type of agriculture is practiced:

In conventional agriculture in the 80's in the area of the Peruvian Coast. cotton crop residues were incorporated into the soil with the tractor. But faced with the increase of an insect (Disdercus peruvianus L) that attacked cotton and a disease, it was decided to burn the crop residues. Subsequently, in intensive crops such as asparagus, grapevine, up to 70 tons of goat and vovine manure were applied.

While in Andean agriculture, the incorporation of organic matter was through cattle and goat manures before the establishment of the crop, there is also a very traditional practice of making the cattle sleep in the plots at determined times, this practice was called the waving But also after the rainy season, the soils are tilled and left on display for three months and then sowing is done, this practice is known as Chakmeo.

Meanwhile, in the jungle of Peru, shifting agriculture is practiced where there is succession and associated polycultures of crops in such a way that the cycle of this practice ends in a forest, which is where a lot of organic matter accumulates

Saludos

Dr Hugo Huamani Ypanqui thank you for your contribution to the discussion

Organic matter contributes to nutrient retention and turnover, soil structure, moisture retention and availability, degradation of pollutants, and carbon sequestration. Such soil fertility management practices include the use of fertilizers, organic inputs, crop rotation with legumes and the use of improved germplasm, combined with the knowledge on how to adapt these practices to local conditions. Soil organic carbon not only improves soil nutrient bioavailability but also affects soil fertility by various other mechanisms and is of central importance for the global C-cycle, which may strongly affect atmospheric CO2-concentrations. Organic matter plays a significant role in crop production and soil health by improving physical, chemical, and biological functions in the soil. Increasing levels of organic matter aid in soil structure, water-holding capacity, nutrient mineralization, biological activity, and water and air infiltration rates. Soil fertility can be increased by altering the pH and air content of the soil and by the addition of fertilizers to the soil. Nutrients can be replenished in the following ways: Fertilizers and manures contain plant nutrients such as nitrogen, phosphorous and potassium, etc. So, when fertilizers and manures are added to the soil in the fields, then the soil gets enriched with nutrients like nitrogen, phosphorous and potassium, etc.