Co-incorporation of hydrotalcite and starch into biochar-based fertilizers for the synthesis of slow-release fertilizers with improved water retention  

作　　者：Jiawei Lu Yongfu Li Yanjiang Cai Peikun Jiang Bing Yu 

机构地区：[1]State Key Laboratory of Subtropical Silviculture,Zhejiang A&F University,Hangzhou 311300,China [2]School of Environment and Resources,Zhejiang A&F University,Hangzhou 311300,China

出　　处：《Biochar》2023年第1期765-777,共13页生物炭（英文）

基　　金：Key Research and Development Project of Science and Technology Department of Zhejiang Province(2023C02019);National Key Research and Development Program of China(2022YFE0127800);National Natural Science Foundation of China(22006018);talent starting-up project of research development fund of Zhejiang A&F University(2034020103);Overseas Expertise Introduction Project for Discipline Innovation(111 Project D18008).

摘　　要：The unsatisfactory nutrient slow-release and water-retention performance of traditional biochar-based compound fertilizers(BCF)severely limit their practical application.Herein,a new type of slow-release fertilizer with high water retention was fabricated via the incorporation of hydrotalcite and starch into BCF,named as HS-BCF.The waterretention and nutrient releasing performance of the prepared HS-BCF and related nutrient slow-release mechanism were investigated.The results showed that the incorporation of hydrotalcite and starch into BCF could increase the soil water-retention ratio by 5-10%points.The accumulated N,P,and K leaching amounts of HS-BCF in soil within 30 days were 49.4%,13.3%,and 87.4%of BCF at most,respectively.Kinetic analysis indicated that the release of nutrients from HS-BCF was attributed to the coupling of the diffusion-controlled and relaxation-controlled mechanism.Moreover,hydrotalcite could bind with P in HS-BCF,contributing to the enhanced durability of P in HS-BCF.Finally,pot experiments showed that the N-P-K utilization efficiencies of HS-BCF were all higher than those of BCF due to a better synchronization between the nutrient release of HS-BCF and the uptake of tomato plants.Overall,the study may provide a promising strategy for simultaneously improving the water-retention and slow-release performance of traditional biochar-based fertilizers.

关 键 词：STARCH HYDROTALCITE Slow-release fertilizer Release kinetics Water retention 

分 类 号：S14[农业科学—肥料学]