How exactly should we recover the other half of agriculture?
Both fruit and straw are the products of agricultural production. People tend to treasure the fruit but overlook the value of the other half, the straw. Doing a good job of the comprehensive utilization of straw is equivalent to recovering the “other half” of agriculture.
Recently, tiny straw has once again become the star of the news. The causal relationship between burning straw and smoggy days has sparked quite a bit of debate. What is gratifying is that this time, beyond the voices of experts, officials and city dwellers, more farmers' voices have appeared: “An acre of corn has over 3000 jin of straw; leaving it in the field is useless, and hauling it out costs freight. At autumn harvest every household is short of labor, so who has time to bother with straw?” “Right after the autumn harvest we plant wheat. Chopped straw with high stubble is inconvenient, so burning it is the easiest way.”
Such voices truly reflect the difficulties in banning straw burning. In the final analysis, it is a problem of comprehensive utilization. As times have developed, straw's function as firewood has basically disappeared, while its other uses, such as biomass fuel, power generation, return to the field and feed, still face many constraints in comprehensive utilization.
Many people call straw the other half of agriculture. This is because in a cycle of agricultural production, both fruit and straw are the products of agricultural production. Fruit is the grain that people treasure, while the value of straw as the other half of the output is often overlooked. Doing a good job of the comprehensive utilization of straw is of great significance for solving agricultural non-point source pollution, promoting sustainable agricultural development and advancing ecological civilization.
The main way to utilize straw is to return it to the field, which is also the common practice in developed countries. The United States produces 450 million tons of crop straw annually, and the amount returned to the field accounts for 68% of straw production. But in our country, the proportion of chopped straw returned to the field is not high. Where is the crux? First, returning straw to the field is costly. It requires high-horsepower agricultural machinery, and fuel consumption and costs are considerably higher than those of ordinary machinery. Although some places provide a subsidy of 10—20 yuan per mu, this is only equivalent to 1/3 of the actual cost, and farmers must bear the rest themselves. Second, the technology for returning straw to the field is not mature. Farmers feel that chopped plots affect sowing and do not experience the benefits of returning straw to the field, so they are unwilling to accept this method.
Apart from returning straw to the field, all other uses of straw require first hauling the straw out of the fields. The technical term for this is “leaving the field,” and it is a key step in commercializing straw. At present, however, the relatively high cost of leaving the field caused by an unsound collection, storage and transportation system has become the main constraint affecting the comprehensive utilization of straw. According to surveys and estimates by the Ministry of Agriculture, the cost of returning straw to the field is about 9%—15% of the net income of a single-season crop, and the cost of leaving the field is about 15%—30%.
To recover the other half of agriculture, we must first rely on policy guidance and subsidies. Our country's existing policies lack corresponding policy measures for weak links such as straw collection, storage and transportation and the application of end products, which is not conducive to forming a complete industrial chain. A series of supporting policies for the comprehensive utilization of straw should be issued at the national level, including subsidies for the application of end products as well as subsidies for returning straw to the field and for agricultural machinery operations. In particular, subsidy policies should be issued to support the construction of straw collection, storage and transportation sites and facilities, and preferential support should be given in areas such as land use, electricity use, transportation and taxation. In response to the problem of insufficient capital investment, a multi-level, multi-channel and diversified investment mechanism should also be formed, with fiscal input as the guide and investment by enterprises and farming households as the main body.
Second, the research, development and promotion of advanced and practical technologies should be accelerated. At present, our country has already developed the “five materials” utilization of straw (biomass fuel, biogas raw material, feed, fertilizer and substrate), but there are still problems with some key technologies and equipment, such as high cost, low efficiency and lack of practicality, resulting in low acceptance among farmers and difficulty in promotion. Therefore, actual demand should be used to drive research and innovation, with more effort devoted to practicality and low cost.
The most critical thing is to establish a market-oriented and industrialized operating mechanism for the comprehensive utilization of straw, so that the hand of the market can play a greater role. With enterprises as the main body, straw collection should be organically linked with ecological planting and breeding, straw energy utilization and straw raw material utilization, to advance specialized production, integrated operation and socialized services, and to explore business models that can be replicated and promoted.