The original intention of eco-agriculture is to carry out crop rotation, intercropping and interplanting in farmland to prevent soil erosion, make fertile soil grow good crops, raise healthy livestock and play the role of combining agriculture and animal husbandry. However, with the rapid development of ecology, the word "ecology" in ecological agriculture has been given new meaning and content.
China's agricultural, ecological and economic scientists have established many eco-agricultural points together with farmers, such as "eco-households", "eco-villages" and "eco-fields", and even the embryonic form of "eco-counties" has appeared. Although these pilot projects have shortcomings such as small scale and lack of modern technology and equipment, they represent the development direction of agriculture.
Rice has been planted from generation to generation in the farmland in southern China, and I am used to it. A few years ago, some clever farmers were unwilling to stick to the rules. They believe that in the past, some people raised fish and duckweed in rice fields, which could make rice fields fertile and grow a large number of aquatic phytoplankton and animals. There are often many pests in rice fields, and these plankton, bugs and Azolla are the favorite bait for fish. Why not combine them? This is the viewpoint of ecological agriculture. Agricultural science and technology workers put forward the technical scheme of "rice, rice and fish" according to the principle of "habitat" in biology and the practical experience of farmers. After experiments and demonstrations with farmers, it was found that rice was cultivated in furrow with good ventilation and good root growth. When fertilizer increases, pests decrease and yield increases. Put duckweed on the water to fix nitrogen and shade, which is equivalent to 30 ~ 35 kilograms of urea nitrogen fertilizer. Fish farming in the water can loosen the soil, eat worms and eat more duckweeds. The yield of fresh fish is 50 ~ 75 kg per mu. A small biological "habitat" technology has doubled the output value of rice fields, turning insects and weeds in rice fields into animal proteins of high-value fish. Now, this technology of "rice, ping, fish" is developing in southern rice areas.
Look, how wonderful ecological agriculture is. Is it a promising modernization project?
In the agricultural ecosystem, people only use the biomass of crops, accounting for 20% ~ 30%, while 70% ~ 80% of the biomass, such as straw, chaff, animal blood, hair, bones, viscera, feces and so on. It contains a lot of nutrients and energy and is often used as fertilizer or fuel. According to FAO research, the crude protein content in animal manure is 50% higher than that in animal feed. Microorganisms in the rumen of herbivores can decompose almost all metabolites of animal feces. Therefore, it is another task of ecological agriculture to utilize biomass at multiple levels and greatly improve the utilization rate of biomass.
1987, Ziyingliu private village, the county head of Daxing, Beijing, was identified as the first ecological farm in China. 120 friends from different countries came to visit.
Since 1982, private villages have taken the road of ecological agriculture, developed aquaculture and processing industries, and implemented comprehensive utilization of organic wastes. The village has initially formed a multi-level biomass utilization system. The village-level scale system is: straw is crushed as feed and sent to livestock farms, animal manure is sent to biogas digesters to produce biogas, and biogas residue is sent to fish ponds, mushroom houses and vegetable fields. Used as feed and culture fertilizer. The family scale system is: chicken manure and pig manure are sent to family small biogas digesters, and biogas residue is used as fertilizer for private farmland and contracted farmland. Due to the implementation of ecological agriculture, 65,438+000 tons of coal are saved every year, environmental pollution is reduced, village sanitation is improved, and per capita income is also increased.
There are many successful examples of eco-agriculture at home and abroad. Although they are still in their infancy, they have shown great vitality. It still has great potential to be developed by human beings.