>>2916<3. Extensive agricultural and rural production and management
One is the lagging development concept. Throughout the ages, from foreign to domestic, scientific research to production, obtaining the highest or higher agricultural output has always been the primary goal and even the ultimate goal of people's diligent pursuit. However, excessive, blind or one-sided pursuit of temporary yield indicators, immediate benefits, or short-term efficiency and efficiency has prompted people to rush to make manual selection and "survival of the fittest" from the start of the cultivation of new agricultural varieties, leading to the intensification of production links. Professional and large-scale operation and management. Large-scale simplification has continuously promoted the cultivation of high-yield "good" varieties and "unscrupulous" supplemented by all comprehensive measures for breeding and cultivation that capture high yields, ensure a bumper harvest and increase benefits, while ignoring the protection of germplasm resources and genetic diversity, and despising the ecological environment and The protection of industrial diversity ignores the long-term, continuity and scientific nature of production increase, growth or development.
The second is the predatory development of agricultural natural resources. Based on the deviation of development concept and the limitation of understanding, the desire to pursue output value, increase income and efficiency, and get rid of poverty and get rich is too strong, and the objective reality of the belief of "relying on mountains to eat mountains, relying on water to draft water" has led to the destruction of forests and reclamation of wasteland from the sea (lake). (Land), blindly introducing species and disorderly development of wildlife resources, and other chaotic phenomena, such phenomena as indiscriminate logging, indiscriminate cultivation, indiscriminate grazing, indiscriminate harvesting, and indiscriminate introduction have been repeatedly prohibited. At the same time, rural construction is disorderly and out of standard, land utilization rate is seriously low, lack of planning, scattered layout, blind comparison, greed for foreign, over-occupation of cultivated land and extravagant waste and other undesirable tendencies coexist, resulting in a negative impact on agricultural resources, environment and biodiversity. Coercion.
The third is excessive agricultural chemicalization. At present, the use of agricultural chemicals represented by fertilizers, pesticides, agricultural films and antibiotics in China ranks first in the world. The use per unit area is several times that of developed countries, and far exceeds the world average level and the internationally recognized upper limit of environmental safety. , And further showed a trend of sustained and rapid growth, with agriculture’s dependence on chemicals reaching more than 50%. At the same time, the effective utilization rate or recovery rate of agricultural chemicals has been hovering at a low level for a long time, resulting in a large amount of chemicals or toxic and hazardous substances remaining in the field or soil, which will cause serious damage to the agricultural ecological environment and biodiversity.
The fourth is unsustainable water conservancy. There are still many extensive, unscientific or unsustainable elements in traditional water conservancy project construction and even modern water conservancy concepts or water conservancy process. For example, excessively large-scale or frequent, blind remote water diversion (diversion) and construction of dams and reservoirs, as well as increasingly hardened, cemented, and linearized river dams, ridges, ditches, and field roads, are greatly improving the drainage and irrigation capacity. At the same time as the level of flood prevention and disaster resistance, it may further lead to the destruction of water ecology or deterioration of the water environment, aggravate the fragmentation of farmland habitat and the crisis of agricultural biodiversity, and weaken the self-purification and self-balancing ability of the agricultural environment.
The fifth is the risk of biochemical. On the one hand, the continuous selection, research, development and promotion of agricultural genetically modified or high-yield hybrid varieties has led to the gradual shrinking and even extinction of traditional local varieties and farm varieties, thereby accelerating the loss of genetic diversity, genetic diversity and farmland ecological diversity. At the same time, it is very easy to cause the invasion and damage of new major diseases and insect pests, resulting in a rapid change in the structure of agricultural organisms. On the other hand, gene drift and pollution, while seriously destroying the genetic integrity, diversity and viability of agricultural organisms, may further promote the growth of new super pests or increase the harmfulness of pests; residues of genetically modified organisms that enter the soil , It produces new toxins and harms soil organisms.
<4. Deteriorating agricultural ecological environment
First, the pollution of cultivated land is serious and the quality is degraded. At present, nearly 20% of the cultivated land in China has exceeded the standard of soil pollutants, about 20% of the cultivated land is polluted by heavy metals, 13 million to 16 million hm2 of cultivated land is polluted by chemical pesticides, and more than 25 million hm2 of farmland is polluted by residual plastic film. Large areas of soil Suffered from the pollution of nitrate, nitrite and other chemical fertilizer residues, the farmland affected by acid rain reached 2,667,000 hm2, and the area of sewage irrigation area was 6.5 million to 7 million hm2. At the same time, the level of cultivated land nationwide is generally low, with poor or poor quality. More than 60% of the cultivated land has no water source protection; more than 40% of the soil is degraded, and the proportion of low- and medium-yield fields is as high as 71%; the soil nutrition imbalance is serious, desertification, saline-alkali Outstanding chemical and soil erosion has intensified.
Second, the water environment is worrying. The environmental report shows that in 2013, China's surface water was generally slightly polluted. 50% of the top ten river systems were polluted; nearly 40% of the nationally controlled lakes reached pollution level; about 60% of the groundwater quality was poor or extremely poor; coastal waters More than 1/3 are polluted, and local pollution is serious.
Third, the quality of the atmospheric environment has declined. Studies have shown that since the founding of New China, the ammonia flux in the national atmospheric environment has increased several times; trace greenhouse gases emitted by the agricultural industry are increasing at a rapid rate; more than 5 million hectares of arable land have suffered varying degrees of air pollution. Currently, less than 1% of cities nationwide have air quality up to standard, and the range, frequency and duration of smog keep setting new records. The continuous deterioration of the agricultural ecological environment has further accelerated the loss of agricultural biodiversity.