Effects On Radish Vegetal Specialties And Quality And Soil Characteristics With Biogas Slurry

There were lots of merits such as Comprehensive nutrition, stable effects, containing both low and quick fertilizer and cheap cost on biogas residue, which could not only support each kinds of nutrient elements, turning elements hard to absorb in the soil into available, reduce the mount of chemical fertilizers and pesticides used and cut production cost, also improve agricultural products qualities and physical and chemical characteristics of soil, increase soil capability of keeping fertilizer and water and avoid damage on soil construction for plenty of chemical fertilizers and pesticides continuously applied. However, seldom researches of imposing biogas residue (biogas liquids and slurries) on radish were reported domestically at present. So researches on how biogas residue influenced radish vegetal specialties, qualities, soil characteristics and safety targets should be help of production of harmless vegetables.As components of biogas residue (BR) were greatly affected by temperature, raw materials concentration and ratio of C and N in raw material, nutrient contents of biogas residue of different areas, raw materials and volumes were studied firstly. Then, engineering and household BR were mixed with chemical fertilizer at 7 different ratios, and the mixtures were imposed on radish. During the growth cycle (from Sep.21st to Oct.31st 2006), foliaceous length (FL), foliaceous thickness (FT), cauline diameter (CD) and yield of radish were measured to choose the best mixing ratio for radish growth. After harvest, radish qualities and soil chemical characteristics were analyzed. At the same time, taking safety into account, pollutants in soil and heavy metals in radish were detected.The results showed that: it was complex and haphazard of changes tendencies of biogas residue nutrient contents influenced by regions; nutrient contents (NC) in biogas liquids (BL) were higher as the raw materials were cow dung or human manure, while the contents of biogas slurries (BS) were higher when the materials were pig or human manure; NC of household biogas liquids (HBL) were universally higher than these of engineering biogas liquids (EBL), NC of BS were pretty different.The best rate of biogas residue and chemical fertilizer (BRBRCF) for engineering biogas residue (EBR) to affect FL of radish remarkably was BR only while the rate of household biogas residue (HBR) was 4:1, the increase rates were 78.08% and 66.14%; the BRBRCFs for both HBR and EBR to influence FT mostly were BR only, the decrease rates were 158% and 131.75%; the BRBRCF for EBR to enlarge CD notably was BR only and the increase rate was high to 199%, while the BRBRCF of HBR was 4:1 and the increase rate was 276.59%; the BRBRCF for EBR to improve radish yield was BR only, and for HBR was 4:1.The BRBRCF for EBR to increase contents of shive and crude protein in radish was BR only, total sugar was 1:1, total acid was 1:2. The BRBRCF for HBR to improve contents of vitamin C, crude protein and shive were 4:1, total sugar was 1:4, total acid was 1:2.The BRBRCF for EBR to improve fertility of soil was BR only or 1:2; the BRBRCF for HBR was 4:1. Moreover, in regard to safety, except Cd in soil and Cr in radish beyond national standards, BR was safe to irrigate and radish safe to eat basically.