The Use Of Agricultural Wastes As Substrate And Its Properties Improvement

Recently, various agricultural wastes largely increase in the production process of agriculture and animal husbandry. It wastes resources and causes serious environmental problems, which is not conducive to agricultural production. Agricultural wastes, as nursery substrate, can effectively solve environmental problems caused by agricultural wastes and can reduce the production cost of the matrix. The experiment materials are cow manure, pig manure, mushroom residue and sawdust and we should make up mixed matrix according to a certain proportion. The objects of study are maturity matrixes fermented for 7 months and 8 months, commercial maturity matrix and commercial maturity matrix added bark. This study investigated the influences of different composting times and added materials on the properties of substrate by the test of physical properties, chemical properties and biological properties on substrate. The main conclusions obtained are as follows:(1) Study on the composting process, the basic properties changes of the substrate.With the increase of composting time,the bulk density of compost matrix density of compost for 8 months was higher than 7 months.The maturity commodity density is higher than the non decomposed matrix.Compost water for 7 months was lower than that of composting for 8 months.The water as commercial substrate was significantly higher than that of the matrix add bark goods.Maybe due to the addition of bark increases, the permeability of the matrix, resulting in water evaporation in the matrix, the moisture content decreased.Composting for 7 months to 8 months, pH matrix, EC decreased.Add bark goods substrate pH, EC was significantly lower than that of commercial maturity matrix,May be added in the pine bark, increases the permeability of the matrix, the ammonia nitrogen volatilization caused, resulting in the decrease of pH.Low ionizable salt ion content in bark,add the bark, the matrix EC decreased.Soil and water 10:1 leaching, the GI, bud length, germination rate of the cabbage were higher than the soil and water ratio 5:1. With the increase of heap rot time, the growth of GI, bud length and germination rate of the young Chinese cabbage increased.. Add bark goods matrix, Chinese cabbage GI, bud length, germination rate was higher than the maturity of commercial substrates. After adding bark, the matrix pH and EC were decreased, the toxicity of matrix was decreased, and the germination rate of the seed increased, so the seed length increased.(2) Study on the composting process, variation of carbon nitrogen and phosphorus of the matrix.The rapid decomposition of organic carbon during matrix composting,some decomposition of water soluble organic carbon,the matrix of water soluble organic carbon content increased.With the increasing of microbial activity,water soluble organic carbon consumption,content reduced.With the increasing time of composting,composting for 7 months to 8 months,water soluble carbon content increased,alkali soluble carbon content decreased; the water soluble carbon content of the maturity of commercial substrates is higher than the matrix add bark goods,the alkali soluble carbon content is lower than the matrix add bark goods.water soluble carbon, alkali soluble carbon content of the commercial substrate is lower than the non decomposed matrix of water soluble carbon.Composting for 7 months to 8 months,,total nitrogen and amino acid nitrogen content showed a downward trend.Add the bark can significantly reduce the total nitrogen content in the matrix,the effect of amino acid nitrogen was not significant.The content of total nitrogen and amino acid nitrogen in the matrix decomposition compared with unfermented substrate,decreased.With the increase of composting time,composting for 7 months to 8 months,The content of ammonium nitrogen in the matrix showed a trend of decline.The content of ammonium nitrogen in the decomposition of matrix and adding pine bark is basically the same.Effect of adding bark on the content of ammonium nitrogen in the matrix is not significant.The difference of ammonium nitrogen in commodity matrix and unfermented matrix significantly.Composting for 7 months to 8 months,the nitrate content did not change;add the bark matrix content of nitrate nitrogen was higher than that of commercial maturity commodity matrix.The content of nitrate in compost matrix was significantly lower than that oin non decomposed matrix.Use the NH4+-N/NO3--N less than 0.5 as the standard,the goods matrix reach the composting standard.With the increase of composting time,composting for 7 months to 8 months, the total P content changed little,the content of totle Pand K increased;The content of P in full maturity were significantly different than the compost substrate 7 and 8 months.Add the bark, matrix P, K content is lower than commercial maturity commodity matrix.(3) Put forward the technology, which uses mineral to improved matrix water retention and water permeability.Add perlite or vermiculite can improve the water absorbing capacity of matrix,increased with the adding proportion.The effect of vermiculite was better than perlite.The maximum saturated water content was reached on the ration of 2:3 both for the additive of perlite and vermiculite.Add perlite or vermiculite can improve the saturated water content of matrix,increased with the the decrease of matrix and perlite adding proportion.The maximum saturated water content was reached on the ration of 2:3 both for the additive of perlite and vermiculite.Add perlite or vermiculite can improve the saturated water content of matrix,increased with the the decrease of matrix and perlite adding proportion.Matrix and perlite ratio of 1:4 is the largest increase in saturated hydraulic conductivity. Saturated hydraulic conductivity of adding vermiculite and the pure matrix conductivity difference.The saturated hydraulic conductivity of adding perlite matrix higher than adding vermiculite, there was extremely significant difference.Matrix saturated hydraulic conductivity and bulk density,initial moisture content was negatively correlated.(4)Put forward rhe technology to improve the substrate germination rate.Addition of calcium carbonate and calcium oxide in matrix, the effect of raw matrix improvement obvious.Advantageous to Chinese cabbage seed germination. with the increased of calcium carbonate and calcium oxide content,the germination rate, germination potential and germination index were increased,When calcium carbonate increased to 4%, reaching the maximum.White seed germination index in the presence of 4% calcium carbonate and 4% calcium oxide matrix had no significant difference.With the addition of 4% calcium carbonate and 4% calcium oxide matrix,cabbage seeds germination fast and neatly,and seed germination rate higher.