Study On The Formulation And Slow-release Performance Of Bagged Fertilizer For Fruit Trees

Traditional orchard fertilization mainly uses trenching and fertilizing,which has high labor intensity,insufficient fertilizer efficiency,and fast nutrient loss.At present,the packaging materials of bagged fertilizers used for fruit tree production generally use nondegradable materials,which can lead to soil degradation and affect fruit tree yield after longterm use.This study focuses on the issues of non-degradable packaging for fruit tree bagged fertilizers,fast nutrient release,and short nutrient release cycles.A bagged slow-release fertilizer for fruit trees was prepared,with the main work and conclusions as follows:(1)A degradable modified starch/PVA composite film was prepared.The study showed that when the mass ratio of starch to PVA was 3:2,adding 4.8% calcium chloride,10%glycerol,and 3% biochar can improve the performance of the starch/PVA composite film material.The water absorption of the treated film material was 25.62%,the water contact angle was 13°,the tensile strength was 16.65 MPa,the elongation at break was 21.53%,and the degradation rate after 90 days was 30.16%.(2)The physical and slow-release properties of fruit tree bagged slow-release fertilizers were studied.Through multiple experiments,the slow-release performance and nutrient release pattern of fruit tree bagged slow-release fertilizers were comprehensively analyzed.The study showed that the results show that bagged slow-release fertilizer with a film material thickness of 1.5 mm(SF1.5)has the best drop resistance,with the probability of damage from high-altitude falls being only 4% and good moisture resistance;the slowrelease effect was significant,with the residual content of total nitrogen,available phosphorus,and soluble potassium in the experimental group increasing by 230.65%,293.33%,and 66.67%,respectively,compared to the control group.(3)The nutrient migration routes and distribution patterns of fruit tree bagged slowrelease fertilizers in the soil were studied.The results showed that compared to conventional fertilization,after six months of applying fruit tree bagged slow-release fertilizers,the mmonium nitrogen,nitrate nitrogen,available phosphorus,and soluble potassium in the soil increased by 8.27%,11.34%,14.06%,and 5.88%,respectively.The nutrient concentration curve was more stable,the nutrient retention time was longer,and soil nutrient loss due to precipitation was effectively reduced.After applying fruit tree bagged slow-release fertilizers to the soil,the nutrient migration situation was as follows: the total nitrogen migration tended to diffuse upwards,the available phosphorus migration tended to vertically diffuse downwards to the plow bottom layer and then horizontally diffuse,and the soluble potassium migrated evenly in all directions.Preparation of degradable bag materials for slow-release fertilizer packaging and promotion of the application of slow-release fertilizer packaging for fruit trees can provide a theoretical basis for scientific fertilization and cost reduction and efficiency enhancement in fruit tree cultivation,promote the development of specialized fertilizers for fruit trees,and promote the green development of agriculture.