"Environmental relocation" of a large number of farms in the Pearl River Delta

Introduction: due to the increasingly serious environmental pollution caused by livestock sewage discharge, a large number of large-scale breeding farms in Pearl River Delta cities such as Shenzhen, Dongguan and Zhongshan in Guangdong Province began to implement the environmental relocation plan, and transferred the capital, technology, marketing network and other advantageous resources to the mountainous areas Experts here pointed out that it is advisable to grasp this business opportunity, combine with fruit planting, introduce large-scale farms, and take the development of pig (cow) - biogas - fruit (vegetable) ecological model as an important economic growth point in mountainous areas Guangdong is the most intensive area among the 12 animal husbandry provinces in China According to statistics, 40 million pigs were sold in the whole province last year, of which more than 40% were sold in large-scale pig farms There are 48000 large-scale pig farms with more than 50 pigs in the whole province, with an annual discharge of 460 million tons of sewage, most of which are directly discharged without effective treatment, seriously polluting water sources and ecological environment At present, the discharge of sewage from large-scale farms in the Pearl River Delta has exceeded that of industrial sewage Chen Renzhong, director of Guangzhou agricultural environmental monitoring station, said that the annual discharge of pig wastewater in Guangzhou is more than 12 million tons, 80% of which is directly discharged to farmland, irrigation River and urban drinking water source without harmless treatment The consequences are worrying Guangzhou xiangmanlou dairy farm was built in 1987 Since 1994, the physical examination for conscription of local farmers is generally unqualified The main problem is that the manure of livestock pollutes the farmland, which leads to serious skin diseases At present, the vast majority of large-scale farms in Guangdong Province are concentrated in the Pearl River Delta With the urbanization and the increase of population density, the conflict between "people and pigs competing for land" in the Pearl River Delta will be increasingly intensified During this year's two sessions, agricultural pollution has become the focus of environmental protection According to experts, similar to Guangdong, large-scale farms are concentrated around the city In Shanghai, Beijing, Nanjing and other large and medium-sized cities, the water pollution load of livestock and poultry breeding industry has exceeded the total pollution load of industrial sewage and domestic sewage Chen Wanzhi, a deputy to the National People's Congress and deputy director of Chongqing Environmental Protection Bureau, said: the feces produced by livestock and poultry breeding in Chongqing is nearly 100 million tons a year In addition, farms also bring air pollution to nearby areas According to relevant experts, there is no mature technology for livestock sewage treatment in foreign countries Generally, anaerobic fermentation technology is used, commonly known as biogas digester However, the biogas digester can only reduce the concentration of BOD and COD in livestock manure by 40% - 50%, and the content after treatment is still dozens of times higher than the relevant national emission standards A complete anaerobic fermentation technology must be equipped with a large-area sun exposure pool, which can meet the discharge standard after fermentation and sun exposure The land area of sewage treatment equipment is far larger than the livestock house itself China's land is scarce, and it's almost impossible to provide a complete set of sun pools Another way to control pollution is "self purification" Chen Renzhong, head of Guangzhou agricultural environment monitoring station, said that according to international standards, self purification can be achieved within 4 pigs per mu of fish pond The pig farm in Guangzhou has 70 pigs at most in one mu of fish pond, and the organic content of the waste water discharged exceeds 1000 times Lin RuiRu, head of Guangdong Provincial Agricultural Environmental Protection and rural energy station, said that for a long time, the state has lacked research and investment in animal husbandry pollution, and animal husbandry wastewater treatment technology is seriously inadequate Since 1960s and 1970s, biogas digesters have been popularized in China, but at that time, the focus was to solve the energy problem in rural areas, and the design of biogas digesters did not consider environmental protection indicators Wan Hongfu, director and doctoral supervisor of the Institute of ecological environment and soil of Guangdong Province, said that adopting the pig biogas fruit (vegetable) model, i.e the supporting fruit forest and vegetable field of the farm, is the best win-win plan for the farm, fruit farmers and vegetable farmers Fertilizer and livestock sewage are two major pollution sources in rural areas A large number of available nitrogen and phosphorus in chemical fertilizer are lost to the water and become the main culprit of eutrophication The large use of chemical fertilizer also leads to the hardening of soil and the decline of soil fertility The waste residue from biogas treatment of farm manure is the best natural organic fertilizer for fruits and vegetables, which can solve the problem of fertilizer abuse Yeqinhai, the "litchi king" of Dongguan City, has started to build a pig farm for its litchi garden The litchi produced has become a brand product and the export situation is encouraging, he said It is reported that Guangdong Province is preparing relevant laws and regulations on pollution control of animal husbandry, and the special treatment of sewage from large-scale farms is imminent The policy of Guangdong Province is to limit the scale of animal husbandry around the city The existing farms will be relocated in an environmentally friendly way and enterprises will be encouraged to move to mountainous areas At present, the relocation has been carried out in an all-round way: Shenzhen agriculture and animal husbandry company moved the pig farm to Zijin County, Guangdong Province, the dairy farm of Guangming farm in Shenzhen city moved to BOLUO County, Guangzhou, Dongguan, Zhongshan and a large number of large-scale farms are in the process of relocation For example, two pig farms with an annual output of 40000 in Dongguan City are seeking cooperation in the mountainous areas of Haifeng City, and Shenzhen agriculture and animal husbandry company focuses on the location To Yunnan, Hunan and other provinces Wan Hongfu said that in the process of adjusting the agricultural structure, the fruit producing areas and the areas with abundant Caopo and Caoshan should seize the opportunity of large-scale breeding farm environmental protection relocation and take the road of sustainable development of breeding and planting industry.