Study Of The Ecotoxicity Of Compost With Attapulgite

Recent years, with the development of large-scale livestock and poultry industry, a large number of manure piled up at random, but the lack of manure treatment technologies. Manure is rich in nutrients for plant growth, is the major source of fertilizer to develop green pollution-free agricultural production. However, because the use of animal feed additives, not only affect the normal growth and development to crops, but also endanger human life and health, at the same time reducing the value of manure. Therefore, by composting and passivator added to reduce the harmful substances in manure, reducing its bioavailability and it is a hot issue about using animal manure in the related field.This paper use the chicken manure was from Ganzhou District of Zhangye, Gansu Province, and the attapulgite was from Gansu Linze to compost of thermophilic aerobic. The attapulgite: chicken manure were 0: 20, 3: 20, 6: 20, 9: 20, 12: 20, 15: 20, and the compost samples from 0d, 4d, 12 d, 20 d, 25 d, 32 d were extracted use the deionized water. To test the changes of germination and seedling growth about four species and the heavy metals(Cu, Zn) enrichent condition in four species by hydroponic experiments, To analyze the influence of four species and the ecological toxicity of heavy metals by add attapulgite to compost.The main conclusions are as follows:(1) Chicken manure composting can effectively promote the germination potential and germination rate of cabbage and the germination index and vigor index of peas, cabbage and wheat. The sensitivity of plant toxicity during composting about the germination potential and germination rate of four kinds of plants was: cabbage> wheat>corn=peas. The sensitivity of plant toxicity during composting about the germination potential and germination rate of four kinds of plants was: cabbage> pea> wheat>corn.(2) Different additions of attapulgite significantly affect the germination potential and germination rate of wheat, and significantly affect the germination index and vigor index of four species. Germination index of peas, cabbage and wheat were highest in treatment A9(attapulgite: chicken manure=9:20), and germination index of corn were highest in treatment A12(attapulgite: chicken manure=12:20), vigor index of four kinds of plants were highest in treatment A9(attapulgite: chicken manure=9:20), when compost is completed.(3) Chicken manure composting can effectively promote the root length of peas, cabbage and wheat. The sensitivity of plant toxicity during composting about the root length of four kinds of plants was: cabbage>wheat>pea>corn. Chicken manure composting only can effectively promote the stem length of cabbage.(4) Different additions of attapulgite significantly affect the root length of peas, cabbage and wheat, and significantly affect the stem length of four species. Root length of cabbage and wheat were highest in treatment A15(attapulgite: chicken manure=15:20), root length of pea was highest in treatment A9(attapulgite: chicken manure=9:20), stem length of wheat, pea and corn were highest in treatment A12(attapulgite: chicken manure=12:20), and stem length of cabbage was highest in treatment A15(attapulgite: chicken manure=15:20), when compost is completed.(5) Chicken manure composting can effectively reduce heavy metals of Cu, Zn in plants, indicating composting have a certain heavy metal passivation effect. The relevance of heavy metals Cu content in wheat, peas and corn and soluble heavy metals Cu are higher than in cabbage. The relevance of heavy metals Zn content in peas and corn and water soluble heavy metals Zn are higher than in cabbage and wheat. Cu enrichment capacity of four plants was: wheat>pea>corn>cabbage, enrichment of Zn capacity was: peas>corn>cabbage>wheat.(6) Different additions of attapulgite significantly affect the heavy metal Cu, Zn content in four plants. For peas and cabbage, in treatment A15(attapulgite: chicken manure=15:20), biological effectiveness of heavy metals Cu, Zn was reducing best. For wheat, in treatment A15(attapulgite: chicken manure=15:20) and A12(attapulgite: chicken manure=12:20) respectively, biological effectiveness of heavy metals Cu and Zn was reducing best. For corn, in treatment A12(attapulgite: chicken manure =12:20) and A15(attapulgite: chicken manure =15:20) respectively, biological effectiveness of heavy metals Cu and Zn was reducing best.(7) The relevance of germination index, root length and stem length in four plants and water soluble heavy metals Cu was better than Zn. It shows that the plant toxicity of heavy metal Cu was obviously higher than Zn. The sensitivity of germination index, root length and stem length in four plants to heavy metal Cu was: root length>stem length>germination index.