The high degree of development of agricultural production, the rapid development of modern livestock and poultry farming, have brought a series of pollution problems to the ecological environment, the

The high degree of development of agricultural production, the rapid development of modern livestock and poultry farming, have brought a series of pollution problems to the ecological environment, the development of eco-agriculture, the conservation of (1) The five-ring industrial chain eco-agriculture change the traditional economic model, take the road of ecological economy, its main implementation of the principle of circular economy.

(2) From the analysis of the main functions of the ecosystem, the main purpose of the establishment of the five-ring industrial chain of eco-agriculture is to make the producers assimilate the material and energy flow more to the part that is beneficial to human beings.

(3) The main components of the gas produced in the biogas fermentation process are CH4 (methane) and CO2.

(4) The ecological engineering principles followed in the five-ring industrial chain eco-agriculture are the principle of material recycling, the principle of systematics and engineering, the principle of wholeness, and the principle of species diversity.

(5) The advantages of this eco-agriculture are mainly manifested in the reduction of environmental pollution and the improvement of comprehensive benefits.

The answers are:

(1) Circular economy

(2) The material and energy assimilated by the producers flow more to the parts that are beneficial to human beings

(3) CH4 (methane)

(4) Principle of material cycle regeneration, principle of systematics and engineering, principle of wholeness, principle of diversity of species (three of them will be scored).

(5) Reduced environmental pollution Improved overall efficiency