Effect Of Biochar And Organic Fertilizer On Camelia Soil And Seeding Of Different Main Cultivars

Camellia oleifera is a important woody edible oil tree species in China.Lacking of coherence,the cultivation and management level of the Camellia oleifera forest is poor,which is in a state of low yield.The ultimate purpose of Camellia oleifera is fruits,in order to gain good quality furits and because of the close relationship between the fruit yield and soil nutrients,we need to have a good understand of soil nutrient status,nutrient absorption and reasonable fertilization,which is an important measure to change the low yield of Camellia oleifera to high yield and high quality.Choosing Camellia cake as materials,pyrolysised to biochar at 300℃ and 600℃,and fermentated to organic fertilizer,which can help us to study the differences of the basic properties of biochar of Camellia cake at different temperatures and organic fertilizer.Red soil and purple soil were collected from Fujian province,and twelve treatments by amending biochar,organic fertilizer or both,separately.All the soil samples were incubated in the indoor at 25℃.The dynamic change of soil mineralization intensity,nutrient elements and enzyme activities were investigated.The pot experiment chose red soil as the experimental soil,Camellia oleifera of Min 43 and Xiang 11 and Camellia chekiangoleosa Hu as experimental plants,amending 300℃ biochar alone and both amending 300℃ biochar mixed with organic fertilizer as treatments.Plant growth index,chlorophyll fluorescence parameters and root activity were investigated.The main conclusions are as follows:(1)The biochar yield significantly decreased,but pH value and the ash content increased with increased temperature.The pH value of 300℃biochar and 600℃ biochar were 5.8 and 10.0.Total C,N,H,H/C and surface functional groups of biochar produced at 300℃ were higher than at 600℃,whereas total P,K,Ca,Mg,Na were decreased.Surface area and total pore volume and the aperture diameter decreased with increased temperature.Compared with biochar,pH value of organic fertilizer is neutral,higher than 300℃ biochar,but lower than 600℃ biochar.The content of C,H of organic fertilizer was less than 300℃ biochar.The content of total N and mineral elements was generally lower than biochars.(2)The CO2 emission of all treatments decreased with the incubation time and gradually stabilized after 30 days.With the condition of adding organic fertilizer,the CO2 emission of soils which was added by biochar was generally higher.The soil respiration of biochar at 300℃ was stronger than that of biochar at 600℃,and the contribution rate of SOC,MBC and DOC was also higher.Without organic fertilizer,the soil mineralization intensity of adding biochar was relatively low.The effects of different treatments on soil nutrient elements were different.600℃biochar promoted the pH,TC,TN,TP and TK.The effect of all treatments on red soil enzyme activity was stronger than that of purple soil.Compared with 600℃ biochar,the effect of 300℃ biochar on soil enzyme activity was better.(3)Both biochar and organic fertilizer could effectively promote growth index of Camellia oleifera and Camellia chekiangoleosa Hu,but the same treatment had different effects on growth index,chlorophyll status and root vigor of different Camellia varieties.Adding 300℃biochar alone could promote the chlorophyll fluorescence parameters of Camellia oleifera of Min 43 and Xiang 11,while it had no obvious effect on each chlorophyll content of Camellia chekiangoleosa Hu.Adding both of 300℃ biochar and organic fertilizer on Camellia chekiangoleosa Hu generally showed inhibitory effect.Biochar and organic fertilizer did not promote root activity of Camellia oleifera,while 300℃ biochar could significantly improve root activity of Camellia chekiangoleosa Hu.(4)Correlation analysis showed that the cumulative amount of soil CO2 emission was significantly correlated with SOC and MBC.There was a positive correlation between soil nutrient elements.Among them,pH and TC,TN,TP,TK,Mg and DOC in red soil and purple soil were significantly correlated,while SOC and DOC,MBC were highly significant correlation.Three kinds of soil enzyme activities and SOC were extremely significant correlation.Different Camellia varieties,the correlation between chlorophyll fluorescence parameters were different.(5)The results of path analysis showed that the direct effects of MBC on the cumulative emissions of CO2 in red soil and purple soil were the largest,the total impact of SOC on red soil was the largest,and total effects of MBC on purple soil was the largest.The pH value had the largest direct effect on urease activities in red soil,and Total C had the greatest impact on acid phosphatase activities in red soil.Total K had the largest direct effect on purple soil urease activities and acid phosphatase activities.SOC had the greatest direct influence on red soil and purple soil invertase activities.SOC had the greatest total effect on enzyme activities of red soil and purple soil.(6)Principal component analysis showed that biochar and organic fertilizer improved purple soil’s comprehensive fertility better than red soil,and biochar of Camellia cake had better effect to improve soil comprehensive fertility than organic fertilizer of Camellia cake,600℃biochar had better effect to improve soil comprehensive fertility than 300℃ biochar.Both adding 600℃ biochar and organic fertilizer could promote pupil soil’s comprehensive fertility best.