Ecological techniques and their application with some case studies in China

Abstract Ecotechniques may be classified into five fundamental types. (1) Series connections of food chains (or production chains): new food chain components (added rings) are added to make full use of substances and energy and to promote ecological efficiency and high production for human needs. The added rings include production rings, increasing beneficial rings, decreasing loss rings, compound rings and processing rings. (2) Parallel connections of symbiosis networks by joining originally independent species, chains or ecosystems to promote symbiosis between them. (3) Multi-step and multi-layer utilization of substances, including waste. The spatial, temporal and trophic structure of an ecosystem or co-ecosystem is adjusted in quality and quantity to use ecological niches as far as possible and to coordinate development. (4) Promoting effective and beneficial circulation of substances, including waste. This includes circulation of materials and regeneration of substances with wastes in living and production processes; exploitation of alternative local resources unexploited at present; and designing and remaking new technological processes without waste. (5) Restoration of ecosystems. This includes two aspects: one is to protect the ecosystem from damage and to minimize the negative impact while exploiting resources, such as choosing ecologically reasonable exploitation techniques or integrated utilization of resources. Another is to promote the recovery of damaged ecosystems and speed up their progress or design new ecological landscapes. Many case studies on the application of these ecotechniques in China are described, including the duck-cum-fish pond, a polyculture of fish in a pond, a rice-fish mutualism system, a mulberry grove-fish pond system, rotation, catching, and rearing in ponds and lakes, and waste water treatment and utilization.