生物炭提高花生干物质与养分利用的优势研究

摘要

[目的]以秸秆为原料生产生物炭可用于改良土壤和提高养分利用率,其与秸秆直接还田以及传统的制作堆肥后还田相比是否具有优势需要用试验来验证,本研究可为生物炭的高效利用提供理论依据.[方法]以传统猪厩肥和秸秆直接还田为对照,连续进行了8年的花生田间微区(2 m2)试验.在氮磷钾总投入量相等的条件下,共设4个处理,分别为秸秆还田(CS)、猪厩肥(PMC)、生物炭(BIO)和基于生物炭的炭基花生专用肥(BF),每个处理重复3次,随机区组排列.试验于2016年在花生苗期、开花下针期、结荚期和饱果成熟期进行采样,测定植株茎叶、根和荚果的干物质和氮磷钾养分积累量,并计算对应的分配情况,探讨其对花生产量的影响.[结果]生物炭处理的花生产量显著高于其它处理,达到7231.7 kg/hm2;生物炭复合肥和猪厩肥处理则相对较低,分别是生物炭处理的82.4％和83.8％,秸秆处理产量最低,为5623.9 kg/hm2.猪厩肥处理的出仁率显著高于其它处理.生育前期各处理的干物质和养分主要在茎叶中积累,从结荚期开始逐渐向荚果中转移.与对照处理相比,复合肥处理的干物质和氮磷钾养分整株积累量在各时期均较高,尤其在结荚期以前保持了良好的荚果干物质和养分分配系数;生物炭处理则至饱果成熟期时呈现出明显优势,干物质积累量达到6295.0kg/hm2,分别高出专用肥、秸秆和猪厩肥处理43.1％、36.1％和50.8％,茎叶分配比例高达34.5％,氮、磷、钾积累量持续增长至236.4 kg/hm2、21.7 kg/hm2、77.8 kg/hm2,显著高于其它处理,但此时期荚果的氮、钾分配系数仅有0.83和0.52,低于对照处理(CS、PMC处理)0.02～0.03和0.15～0.21.[结论]在氮磷钾养分投入量相等、不考虑有机碳投入量的前提下,施用生物炭、炭基复合肥和猪厩肥效果均显著好于秸秆直接还田;生物炭可显著提高花生整株的干物质量和氮磷钾积累量,特别是提高生育后期的干物质和养分分配量,促进产量的提高,对花生高产增效有良好的促进作用;炭基复合肥在花生进入结荚期后,对花生干物质及养分积累分配的促进作用减弱,效果与施用猪厩肥相当.因此,在本试验条件下,生物炭直接施用具有维持其养分长期稳定释放,提高花生产量和肥料养分利用率的作用.%[Objectives] There have been some queries on the necessaries of production and application of biochar.We compared the effects of biochar with other organic materials to testify biochar's advantages.[Methods] Local field experiment of micro plots (2 m2) was conducted for eight years using peanut as tested materials.In the base of the same N,P and K input and without thinking about carbon input,four treatments were set up as biochar (BIO),biochar-based formula fertilizer (BF),piggery manure compost (PMC) and corn straw-returning (CS).Samples were collected in stages of seedling,flowering needle,podding,maturation of peanut in 2016.The dry matter and N,P,K contents in roots,stems and leaves were measured,and the yields of peanut were investigated at mature stage.[Results] The peanut yield of BIO (7231.7 kg/hm2) was significantly higher than those of BF and PMC (accounting for 82.4％ and 83.8％ of BIO respectively) and the lowest treatment was CS (5623.9 kg/hm2).The peanut shelling percentage of PMC was significantly higher than those of other treatments.It was different that the characteristics of dry matter accumulation and nutrient distribution of four growth periods among different treatments.The dry matter and NPK mainly accumulated in stem-leaf in the earlier stages,and turned to pod after the podding stage.BF had a higher content of dry matter and NPK,especially had a higher nutrient partition coefficient before the stage of podding compared with the control treatments.BIO had obvious superiority in dry matter accumulation at the maturation stage (6295.0 kg/hm2),which was significantly higher than those ofBF,CS and PMC (exceeded 43.1％,36.1％ and 50.8％,respectively).N,P,K accumulation of BIO continued to increase to 236.4 kg/hm2,21.7 kg/hm2 and 77.8 kg/hm2,respectively,meanwhile the ratio of dry matter in stem and leaf reached to 34.5％,which was significantly higher than that of the control.However,the N and K distribution coefficients in pod of BIO at the maturation stage were only 0.83 and 0.52 respectively,and were lower by 0.02-).03 and 0.15-0.21 than those of the controls (CS and PMC),respectively.[Conclusions] Under the experimental conditions,all the biochar,biochar-based formula fertilizer and piggery manure compost are more effective than straw returning in peanut yield.The application ofbiochar shows significant higher effect than biochar-based formula fertilizers and piggery manure compost in promoting the dry matter and NPK accumulation,especially in the dry matter and nutrient distribution in late growth period,which is conducive to higher yield and nutrient use efficiency of peanut.Biochar-based formula fertilizer and piggery manure compost show similar effect in yield and nutrient accumulation and distribution.Therefore,biochar application is recommended for fully playing its role in maintaining stable nutrient supply during the whole peanut growing season and achieving both high yield and high fertilizer nutrient efficiency.