Soil formula fertilization is to test the soil, understand the content of various elements in the soil, on the basis of reasonable fertilization, to achieve a balanced supply of various nutrients, maximize the effect of fertilization, reduce the use of fertilizer, improve the utilization rate of soil nutrients, labor saving, cost saving and increase yield.

In 2018, the kunming green city fertilizer team conducted a soil survey in yuanmou county to help agricultural growers conduct agricultural operations in accordance with local conditions, provide accurate fertilization, improve fertilizer utilization rate, reduce fertilizer consumption and agricultural production costs, improve soil properties, reduce agricultural production pollution, and improve crop yield and quality. The specific operations are as follows:

I. sampling process

(I) sampling time

15 days before the crop is harvested, or before fertilization begins.

(ii) selection of sampling points

1. According to the area occupied by the soil to determine the number of sampling, to ensure that enough sampling points, generally about an acre to take 3-5 points, 2-3 acres of 7 points, the area is larger, the number of sampling points will also increase, sampling location with the five-point method, s-shaped sampling. As shown in figure:

2. If the terrain, slope direction and slope are relatively uniform, a few points can be taken; Different plots, different soil quality, need to take more or take points block.

3. Staggered fertilization area, between plant spacing or row spacing.

(3) soil depth and method

Soil drilling method: select 3-5 points for each soil sample, remove the surface soil when sampling each point, and insert the soil drill vertically into the soil at a depth of 5-25cm in the root distribution layer, and take 1-2kg for each point. Soil with a spade: first determine the sampling point, remove the surface soil, and dig a v-shaped soil pit with a spade at a depth of about 5-25cm (the pit depth of all sampling points in the same piece of land should be the same). Then mix the soil sample evenly and divide the sample by quartering method, as shown in the following figure:

Dry, crush, seal up and submit soil samples for inspection.

Ii. Testing items and objectives

Soil physical and chemical properties, the measurement of a large number of elements and trace elements, determine whether the soil is deficient in;

Soil test results, to provide recommendations for targeted fertilization, fertilizer conservation, balanced fertilization.

Matters needing attention

1. Do not take samples during fertilization. The time from fertilization should be more than 15 days.

2, do not in the head, ditch, moved the soil, heap fertilizer place sampling.

3. The quantity shall be at least 500g at the time of inspection.

4. Soil shall be taken strictly in accordance with the regulations, and the distance between sampling points shall be appropriate, and the span shall not be too large.

The purpose of this project is to improve the land use rate, scientific farming, according to the scientific means of soil census, summed up the field plot, suitable for planting varieties, crops need a variety of fertilizer, the amount needed, analysis, so as to improve crop yield.