Biological Productivity And Ecological Effects For Camellia Oleifera Agroforestry Systems

The farmers have been planting Camellia oleifera in the hilly and upland areas for a long time in Lishui,the southwest of Zhejiang Province.The soil condition of the cultivated land is poor,soil erosion is serious and the fertility is difficult to recover.In the early growth stage of Camellia oleifera,the investment of management is big,the investment recovery period is long,and the enthusiasm of the farmers is negtive,which seriously restricts the healthy development of Camellia oleifera industry.Camellia oleifera agroforestry has been one of the effective measures to solve these problems.However,there is little research on the dynamic changes of the growth rhythm,the micro environment and the soil nutrient elements.In this paper,with 4-year-old "Changlin No.40" Camellia oleifera in Xian Ren Village,Longquan,Lishui City as test materials,Camellia oleifera+peanut,Camellia oleifera+soybean,Camellia oleifera+rice and Camellia clean tillage(CK)were determined by monitoring and sampling,lab analysis on different integrated management model of crop growth rhythm and micro environmental factors,soil physical and chemical properties of dynamic changes,to clarify the different Camellia oleifera agroforestry models of the impact on the growth of Camellia oleifera tree and the economic benefits of agroforestry.The main results are as follows:(1)The different Camellia oleifera agroforestry impact on the micro environmental factors the results of the study show that Camellia+peanut,Camellia+rice,Camellia+soybean agroforestry models could reduce the high summer temperature,light intensity,soil temperature and air relative humidity from July to October.Among them,the daily mean air temperature in August by clean tillage could reach 37.7 ℃;however,Camellia+peanut,Camellia+rice,Camellia+soybean agroforestry models were 1.6%,8.5%,2.4%lower than Camellia clean tillage.August daily average relative humidity were 7.42%,20.07%and 10.29%higher than tillage camellia,the average light intensity were 3.22%,16.76%and 10.69%lower than tillage camellia,the soil temperature were 27.35%,24%and 25.48%lower than tillage camellia.(2)The different Camellia oleifera agroforestry impact on crop height,aboveground biomass,underground biomass,root length,root surface area showed a trend of increase has been in a growth period,while the root shoot ratio showed a changing trend from falling.In addition to the target harvest(total biomass 17.3%-28%)as harvest full,biomass return rate reached 71%～82.7%,the stem,leaf and root parts are returning in various ways,help to improve the plowing tillage layer,improve soil fertility,accelerate the maturation of soil Camellia oleifera agroforestry models.(3)The different Camellia oleifera agroforestry impact on soil physicochemical properties showed that Camellia+peanut,Camellia + rice,Camellia + soybean agroforestry models improved soil moisture,reduce soil bulk density,increase soil porosity.In 2016,Camellia+peanut,Camellia +rice,Camellia+soybean agroforestry models pH was 16.43%,19.44%,13.19%higher than clean tillage.The ammonium nitrogen content were 57.95%,45.64%,68.83%higher than clean tillage,organic matter content were 41.44%,21%and 43.67%higher than clean tillage,the content of available phosphorus were 22.76%,35.34%and 33.59%higher than clean tillage,effective potassium content were 90.95%,59.16%,101.14%higher than clean tillage.The compound management model can effectively improve the content of medium and trace elements,and improve the physical and chemical properties of soil in the Camellia oleifera agroforestry system.(4)The different Camellia oleifera agroforestry impact on the growth of Camellia oleifera showed that Camellia+peanut,Camellia + rice,Camellia + soybean agroforestry models in Camellia cultivation were 17.19%,22.63%,27.96%higher than clean tillage,the diameter ratio of Camellia 14.85%,9.6%and 17.68%higher than clean tillage,east and west crown ratio were 5.6%,5.8%,17.65%higher than clean tillage,South and north crown ratio were 2.7%,7.5%and 14.93%higher than clean tillage,spring shoot length ratio of 34.36%,18.5%and 47.19%higher than clean tillage,more than the number of spring shoots of Camellia 39.1%,18.28%tillage and 50.52%spring shoot diameter ratio 11.35%,7.56%and 20.54%higher than clean tillage.Bud number were 50.16%,18.46%and 56.87%higher than clean tillage.Compared with clean tillage,the young Camellia oleifera agroforestry system mode can significantly increase the economic income of Camellia oleifera growers,and the economic benefit per hm2 reaches 11438 yuan,14850 yuan and 10940 yuan.In summary,three kinds of Camellia oleifera agroforestry models significantly increased the biomass accumulation of Camellia plantation,improved the forest microenvironment and physicochemical properties,thus improving the Camellia oleifera root vigor,increase the absorption of nutrients,thereby affecting plant height,diameter,crown width,spring shoot growth.Promote the Camellia oleifera growth.In this paper,the Camellia oleifera agroforestry models of biomass accumulation,micro environmental factors,the growth of Camellia oleifera tree,economic benefits can be used to promote the application of the model in the new forest area of hilly and mountainous areas.