1. Strong ability to maintain fertilizer. For the soil covered with black film, the organic matter is in a normal cycle due to stable soil temperature changes. Measurements show that the total nitrogen, organic matter, available potassium, alkaline nitrogen and other nutritional indicators in the soil under the black film cover cultivated crops are compared Covering the transparent film has different degrees of improvement.
2. Good water retention capacity. According to the test, the water content of 5 cm underground after the black film is covered is 4-10% higher than that of the transparent film no matter whether it is two days after the cover or 35 days after the cover.
3. Prevent adverse effects. The black mulch film has low light transmittance and less radiant heat transmission, so it can make the soil temperature of the covered soil change little. According to the test, the soil temperature covered by black film is 1-3℃ lower than that with transparent film during the plant growth period. Due to the small increase in temperature, it is beneficial to promote the normal growth of crop roots, especially the growth of tomatoes, kidney beans, sweet peppers and other vegetables that do not require high soil temperature.
Fourth, increase vegetable output. Because black mulch film has less soil temperature increase than transparent film, especially for some crops that require low soil temperature for roots, such as tomatoes, string beans, cowpea, late-maturing watermelon, etc., both early and total yields can be more transparent than mulching The height of the membrane. According to the experiment, the yield increase effect of tomatoes covered with black film is obvious, and the increase rate can reach 11.8%.
5. Inhibit weed growth. Weed damage is a serious problem when mulching with transparent film. After switching to agricultural black mulch, ground weeds are difficult to grow due to insufficient light conditions. Measurements show that after covering with black film with a light transmittance of 5%, the soil is almost No weeds. When the agricultural black mulch with a light transmittance of 10% is used, although weeds grow in the soil, the growth ability is weak and will not cause disaster.