Humic acid(HA),a fairly stable product of decomposed organic matter that consequently accumulates in ecological systems,enhances plant growth by chelating unavailable nutrients and buffering pH.We examined the effect of HA derived from lignite on growth and macronutrient uptake of wheat(Triticum aestivum L.)grown in earthen pots under greenhouse conditions.The soils used in the pot experiment were a calcareous Haplustalf and a non-calcareous Haplustalf collected from Raisalpur and Guliana,respectively,in Punjab Province,Pakistan.The experiment consisted of four treatments with HA levels of 0(control without HA),30,60 and 90 mg/kg soil designated as HA0,HA1,HA2 and HA3,respectively.In the treatment without HA(HA0),nitrogen(N),phosphorus(P),and potassium(K)were applied at 200,100 and 125 mg/kg soil,respectively.Significant differences among HA levels were recorded for wheat growth(plant height and shoot weight)and N uptake.On an average of both soils,the largest increases in plant height and shoot fresh and dry weights were found with HA2(60 mg/kg soil),being 10%,25%and 18%,respectively,as compared to the control without HA(HA0).Both soils responded positively towards HA application.The wheat growth and N uptake in the non-calcareous soil were higher than those of the calcareous soil.The HA application significantly improved K concentration of the non-calcareous soil and P and NO3--N of the calcareous soil.The highest rate of HA(90 mg/kg soil)had a negative effect on growth and nutrient uptake of wheat as well as nutrient accumulation in soil,whereas the medium dose of HA(60 mg/kg soil)was more efficient in promoting wheat growth.
Increasing crop yield and fertiliser nitrogen(N)-use efficiency is important for productive agricultural systems with a reduced environmental footprint.The aim of this study was to assess the effect of slow release brown coal-urea(BCU)fertiliser on the gaseous N losses,biomass yield and N uptake by silver beet(Beta vulgaris L.)compared to commercial urea.Two soils were amended with urea,BCU1(22%N)or BCU2(17%N)as N fertiliser at the rate of 50 or 100 kg N/ha.Five gas sampling periods were undertaken to measure the loss of N as N2O and NH3.After 10 weeks,biomass,N concentration,and N uptake of silver beet,and mineral and mineralisable N of post-harvest soil were measured.BCU substantially increased fertiliser N availability and uptake by silver beet,reduced N2O emission by 29%and NH3 emission by 36%compared to urea alone,irrespective of soil type.Compared to urea,BCU blends increased biomass yield by 27%and 23%in a Tenosol and Dermosol soil,respectively.In addition,application of BCU fertiliser substantially enhanced the potentially mineralisable N and organic carbon content of soil.These results provide evidence that granulation of urea with brown coal(BC)can increase silver beet N-use efficiency and yield in different soil types,and more work is now required to validate this technology for other crops.
Humic acids (HA) are organic molecules that play essential roles in improving soil properties, plant growth, and agronomic parameters. The sources of HA include coal, lignite, soils, and organic materials. Humic acid-based products have been used in crop production in recent years to ensure the sustainability of agriculture production. Reviewed literature shows that HA can positively affect soil physical, chemical, and biological characteristics, including texture, structure, water holding capacity, cation exchange capacity, pH, soil carbon, enzymes, nitrogen cycling, and nutrient availability. This review highlights the relevance of HA on crop growth, plant hormone production, nutrient uptake and assimilation, yield, and protein synthesis. The effect of HA on soil properties and crops is influenced by the HA type, HA application rate, HA application mode, soil type, solubility, molecular size, and functional group. This review also identifies some knowledge gaps in HA studies. HA and its application rate have not been tested in field experiments under different crops in rotation, nitrogen fertilizer forms, sites and climatic conditions. Furthermore, HA chemical and molecular structures, their water and alkaline soluble fractions have not been tested under field experiments to evaluate their effects on crop yield, quality, and soil health. The relationship between soil-plant nutrient availability and plant nutrient uptake following HA application should also be further studied.
In sustainable agriculture, seeking eco-friendly methods to promote plant growth and improve crop productivity is a priority. Humic acid (HA) and plant growth promoting rhizobacteria (PGPR) are among the most effective methods that utilize natural biologically-active substances. The aim of the present study was to analyze the effect of the presence of HA on potato (Solanum tuberosum L.) inoculation with PGPR (Bacillus megatorium and Bacillus subtilis) when compared to control and recommended doses of NPK. Seed tubers treated by humic acid (200, 400, and 600 kg ha−1) and PGPR, separately or in combination, and NPK (50% and 100%) were planted into soil and untreated soil. Treatments were assessed for plant growth, classified tuber yields, quality, and mineral contents of potato tubers. There were highly significant increases in potato growth, tuber yields, and quality in PGPR and HA inoculated crops. Tuber size, weight, specific gravity, dry matter, starch, protein, and mineral contents (except Cu) were improved with PGPR treatments and further increased when administered with humic acids. Inoculation with PGPR mixed culture and 400 kg ha−1 HA increased total potato tuber yield by about 140% while conventional single treatment of 100% NPK fertilizer only led to an increase in potato production of 111% when compared to the control. The results demonstrated that this integrated approach has the potential to accelerate the transformation from conventional to sustainable potato production.
Humic substances (HS) are originated from naturally decaying biomass. The main products of HS are humic acids, fulvic acids, and humins. HS are extracted from natural origins (e.g., coals, lignite, forest, and river sediments). However, the production of HS from these resources is not environmentally friendly, potentially impacting ecological systems. Earlier theories claimed that the HS might be transformed from lignin by enzymatic or aerobic oxidation. On the other hand, lignin is a by-product of pulp and paper production processes and is available commercially. However, it is still under-utilized. To address the challenges of producing environmentally friendly HS and accommodating lignin in valorized processes, the production of lignin-derived HS has attracted attention. Currently, several chemical modification pathways can be followed to convert lignin into HS-like materials, such as alkaline aerobic oxidation, alkaline oxidative digestion, and oxidative ammonolysis of lignin. This review paper discusses the fundamental aspects of lignin transformation to HS comprehensively. The applications of natural HS and lignin-derived HS in various fields, such as soil enrichment, fertilizers, wastewater treatment, water decontamination, and medicines, were comprehensively discussed. Furthermore, the current challenges associated with the production and use of HS from lignin were described.
Processes of N transformation in soil as affected by application of the three kinds of urea fertilizers, conventional urea (U), humate-coated urea (U_HA), and urea treated with the urease inhibitor NBPT (U_UI), are examined in a model laboratory experiment. Effects of urea fertilizers on soil chemical (content of water-extractable N-NH4 and N-NO3), and microbiological properties (rate of actual and potential N2O emission, basal and substrate-induced respiration, microbial biomass C, emission of ethylene) are focused to answer the following questions: (i) whether humate-coated urea has the ability to decrease N losses in soil; and (ii) how it affects soil biological activity comparable to synthetic urease inhibitor. The results showed that U_HA demonstrated advantages comparable to U in its ability to decrease N losses in soil: it increased N-NH4 content by 35%, reduced nitrate content by 9%, and decreased N2O emissions by 50%. U_HA promoted basal soil respiration by 10% and the specific activity of the soil microbial community by 7%, providing the highest metabolic quotient qCO(2). Comparably to NBPT-treated U, U_HA mainly shows intermediate results between U-UI and conventional U. Considering the low cost of raw humates, U-HA can be regarded as a promising tool to decrease N losses in soils.
This work focused on cost-effective and collective adsorption of radionuclides followed by their sub-sequent selective desorption,which is necessary for separation.The potential of humic acid,a low-cost adsorbent,for the removal and recovery of Cs(Ⅰ)and Sr(Ⅱ)from simulated reactor waste,was investigated.Experimental parameters like solution pH,adsorbent dose,contact time and temperature were optimized.FT-IR of humic acid before and after adsorption was compared.Selective desorption of both the radionuclides was achieved with desorbing agents-citric acid and HCl.The process was governed by rapid kinetics where 91±2%of Cs(Ⅰ)and 83±2%of Sr(Ⅱ)was adsorbed within 10 min.Data modelling revealed that the process follows pseudo-second-order kinetics,and is spontaneous,feasible and exothermic,with positive entropy indicating a high affinity of humic acid for the metallic ions.Maximum desorption of 97±2%was obtained for Sr(Ⅱ),and 82±2%for Cs(Ⅰ).Thus,the adsorption of investigated radionuclides by humic acid and their desorption was time-efficient,economical and environmentally a benign alternative for the removal and recovery of Cs(Ⅰ)and Sr(Ⅱ).
Abstract This study was conducted in the farmer field between the years 2014 and 2015. In this study, 3 doses of potassium (K) (0, 10, and 20 kg da−1) of K2SO4 (50% K2O) fertilizer and 3 doses of humic acid (HA) (0, 20, and 40 kg da−1) (85% HA) were used. Increase in the HA dose reflected significant effects on pH, salt, organic matter, phosphorus, magnesium, iron, and manganese contents of the experiment area at p < .01 level. It was determined that increased potassium applications affected the salt, magnesium (Mg), iron (Fe), and copper (Cu) contents at p < .01 level. Increased HA application on plant growth criteria had a significant effect on biological yield, grain yield, and harvest index (p < .01). However, K did not reflect any effect on the growth stage of wheat. Increased number of HA applications on grain and straw nutrient content were found to have significant (p < .01) effects on P, K, Ca, Mg, Fe, and Zn. Increased potassium applications had an effect on the P, K, Mg, Fe, and Zn contents with a significant level (p < .01). It was observed that HA applications were more effective than potassium applications on both general soil properties and yield and nutrient content.
Cadmium (Cd) is a toxic and very mobile heavy metal that can be adsorbed and uptaken by plants in large quantities without any visible sign. Therefore, stabilization of Cd before uptake is crucial to the conservation of biodiversity and food safety. Owing to the high number of carboxyl and phenolic hydroxyl groups in their structure, humic substances form strong bonds with heavy metals which makes them perfect stabilizing agents. The aim of this study was to determine the effects of humic and fulvic acid (HA + FA) levels (0, 3500, 5250, and 7000 mg/L) on alleviation of Cadmium (Cd) toxicity in garden cress ( Lepidium sativum ) contaminated with Cd (CdSO 4 .8H 2 O) (0, 100, and 200 Cd mg/kg) under greenhouse conditions. Our results showed that, Cd stress had a negative effect on the growth of garden cress, decreased leaf fresh, leaf dry, root fresh and root dry weights, leaf relative water content (LRWC), and mineral content except for Cd, and increased the membrane permeability (MP) and enzyme (CAT, SOD and POD) activity. However, the HA + FA applications decreased the adverse effects of the Cd pollution. At 200 mg/kg Cd pollution, HA + FA application at a concentration of 7000 mg/L increased the leaf fresh, leaf dry, root fresh, root dry weights, stem diameter, leaf area, chlorophyll reading value (CRV), MP, and LRWC values by 262%, 137%, 550%,133%, 92%, 104%, 34%, 537%, and 32% respectively, compared to the control. Although the highest H 2 O 2 , MDA, proline and sucrose values were obtained at 200 mg/L Cd pollution, HA + FA application at a concentration of 7000 mg/L successfully alleviated the deleterious effects of Cd stress by decreasing H 2 O 2 , MDA, proline, and sucrose values by 66%, 68%, 70%, and 56%, respectively at 200 mg/kg Cd pollution level. HA + FA application at a concentration of 7000 mg/L successfully mitigated the negative impacts of Cd pollution by enhanced N, P, K, Ca, Mg, Fe, Mn, Cu, Mn, Zn, and B by 75%, 23%, 84%, 87%, 40%, 85%, 143%, 1%, 65%, and 115%, respectively. In addition, HA + FA application at a concentration of 7000 mg/L successfully reduced Cd uptake by 95% and Cl uptake by 80%. Considering the plant growth parameters, the best results were determined when HA + FA concentration was 7000 mg/L. We have shown that, it is critical to apply a humic substance with high percentage of FA, which was 10% in this study, to mitigate the adverse effects of heavy metal stress on plant growth. In conclusion, the application of HA + FA may be suggested as an effective solution for reducing the Cd uptake of the plants by stabilizing Cd in soil and preventing translocation of Cd from the roots of plant to its shoot and leaves.
Climate change can alter peatland plant community composition by promoting the growth of vascular plants. How such vegetation change affects peatland carbon dynamics remains, however, unclear. In order to assess the effect of vegetation change on carbon uptake and release, we performed a vascular plant‐removal experiment in two Sphagnum ‐dominated peatlands that represent contrasting stages of natural vegetation succession along a climatic gradient. Periodic measurements of net ecosystem CO 2 exchange revealed that vascular plants play a crucial role in assuring the potential for net carbon uptake, particularly with a warmer climate. The presence of vascular plants, however, also increased ecosystem respiration, and by using the seasonal variation of respired CO 2 radiocarbon (bomb‐ 14 C) signature we demonstrate an enhanced heterotrophic decomposition of peat carbon due to rhizosphere priming. The observed rhizosphere priming of peat carbon decomposition was matched by more advanced humification of dissolved organic matter, which remained apparent beyond the plant growing season. Our results underline the relevance of rhizosphere priming in peatlands, especially when assessing the future carbon sink function of peatlands undergoing a shift in vegetation community composition in association with climate change.
腐植酸肥料是传统化肥实现减施增效中的一类高效肥料产品,在改善作物品质、提高作物产量、调控土壤环境等方面发挥着重要作用.本文主要从物理、化学、生物学方面系统阐述了腐植酸肥料在作物根际土壤微环境中的作用效应,并就农田土壤中普遍存在的质量退化问题提出了腐植酸肥料发展方向.
众所周知,土壤是指地球表面的一层疏松的物质,由各种矿物质、有机质、水分、空气、微生物等组成,能生长植物.土壤是不可再生资源,1厘米土壤的形成需要1000多年的时间.土壤维持自身活力,保护生物多样性,支撑粮食安全生产,调节温室气体排放并促进植物、动物和人类健康.没有土壤,一切生命都将不复存在.其中,腐植酸的贡献居功至伟,它创造了土壤结构,使得土壤具备保水保肥的能力.值此"第八届全国土肥和谐大会"召开之际,让我们共同回顾土壤与腐植酸相互依存,为生态环境提供多重效益的经典论述.
垃圾堆填是垃圾处理重要方式之一,其过程会产生大量渗滤液,垃圾渗滤液溶解性有机质(landfill leachate dissolved organic matter,LL-DOM)是垃圾渗滤液产生环境风险的主要来源.为探究LL-DOM的研究热点与前沿,基于文献计量与数据可视化分析软件Cite Space对Web of Science数据库进行了文献统计分析.结果表明,研究热点主要有吸附、腐殖质、污水污泥研究、平行因子分析、微生物群落、荧光光谱、混凝絮凝工艺等;过去 20 年的主要研究内容包括了渗滤液溶解性有机质组分识别及处理工艺优化研究两方面.结合文献调研分析认为,新兴表征方法及其数据处理、结果分析方法的研究与发展是进一步识别LL-DOM不同种类污染物的关键;同时,多种技术组合,以生物处理和物理化学技术互补的方式进行LL-DOM处理,比单一处理技术综合效果更为理想.
1974年,我国开始有组织地开发利用腐植酸肥料;11月5日—15日,"全国腐植酸类肥料试验推广经验交流会"经国务院批准后在广东湛江和广西南宁相继召开,时任国务院副总理的王震同志亲自参加了会议并发表了讲话;11月16日,在王震副总理的亲自推动下,国务院转发燃化部、农林部《关于积极试验、推广和发展腐植酸类肥料报告》的通知(国发[1974]110号).至今,腐植酸肥料的知名度、美誉度、影响力持续提升,腐植酸肥料的金字招牌越来越亮,这得益于一代代、一批批腐植酸人持续50年的接力赛.2021年12月18日,首届"开展田园新生活运动,寻找最美腐植酸人"活动在海南海口举行,点燃了腐植酸人开创新田园运动的满腔激情,传递了大美腐植酸人的革命精神.新时代是奋斗出来的,腐植酸人的大美精神需要代代相传.值此纪念和庆祝国发[1974]110号文件发布50年之际,协会决定面向全国腐植酸肥料行业、腐植酸营养效素产业体,举办2023年度"开创田园新生活运动,寻找最美腐植酸人"活动,旨在弘扬和传承腐植酸人矢志从业、恪精恪勤、奋力拼搏、舍我其谁的主人翁精神,进一步激发新一代腐植酸人守正创新、奋勇拼搏,推动田园新生活运动实现更加伟大的革命.现将评选活动的有关内容通知如下.
为实现减肥增效、绿色生产,通过设置不同施肥方式探究优化小麦养分管理措施.以减量施氮肥、不同比例腐植酸控释肥替代及腐植酸控释氮肥替代后减肥入手,设置 8 个处理:不施氮肥(CK);农民传统施氮肥(CCF);控释氮肥等量替代农民传统施氮肥(OF);农民传统施氮肥与控释氮肥配合施用(CCRF);控释氮肥+腐植酸(CRF);控释氮肥减施 25%+腐植酸(75%CRF);控释氮肥减施 33.3%+腐植酸(66.7%CRF);控释氮肥减施 50%+腐植酸(50%CRF).结果表明:(1)相较于CK,OF处理小麦籽粒产量增加了 14.97%,CRF处理籽粒产量进一步增加了2.81%,在添加腐植酸的基础上进行减肥处理,75%CRF处理籽粒产量仍高于OF处理,高出1.82%,继续减少施肥量,地上部生物量及产量有下降的趋势,但其之间差异未达显著水平.(2)相较于CCF处理,OF处理可显著增加氮素累积吸收量(16.38 kg/hm2),CRF处理氮素累积吸收量进一步增加了 8.57 kg/hm2,在此基础上进行减肥处理,除 50%CRF外,其余 2 个处理氮素累积吸收量均显著高于OF处理,增幅为 16.41、15.84 kg/hm2,从氮肥偏生产力来看,相较于OF处理,在减量施肥的基础上添加腐植酸均可有效提高氮肥偏生产力,增幅范围为 35.76%～96.77%,以 50%CRF处理的氮肥偏生产力最高.(3)小麦拔节期,相较于CCF处理,除 50%CRF处理外,其余各处理硝态氮含量均显著增加了 34.5%～61.93%,其中以 75%CRF处理最高,小麦收获期,各处理硝态氮、铵态氮并无明显变化.
土肥是粮食生产的根本.在实现"双碳"目标背景下,我们深刻认识到,土壤碳库是地球陆地生态系统中最大的碳库,有机耕作土壤能吸收大气中41％的温室气体,源于土壤有机物中的核心物质腐植酸.大力反哺黑色腐植酸、腐植酸本色肥料义不容辞.正如国际肥料工业协会所言,腐植酸介生于食物链,让土壤更肥沃,让食物更安全,让生活更美好.早在1974年11月,时任国务院副总理的王震同志亲自主持了在广东湛江举行的"全国腐植酸肥料试验推广经验交流会",22个省(市)燃化局、农局负责人、大专院校、科研单位、农村干部共900多人参加.随后国务院转发燃化部、农林部《关于积极试验、推广和发展腐植酸类肥料报告》的通知(国发[1974]110号文件),腐植酸肥料从此走上了农业大舞台.值此我国腐植酸类肥料大规模开发应用50年之际,协会决定在广东湛江这个具有历史意义的地方,举办"第八届全国土肥和谐大会",以汇聚土肥新生力量,肩负起实现"双碳农业"的新使命.
探讨了黄腐酸套餐施肥A、不含黄腐酸套餐施肥B和常规施肥C对莲花白(Brassica oleracea L.var.capitata)生长,品质及产量的影响,旨在为蔬菜作物套餐施肥提供理论依据和可行性方案.结果表明:莲花白莲座期,套餐施肥A与常规施肥C相比,叶宽、茎粗、鲜重、地上部鲜重,分别增宽12.59%、增粗6.77%、增重34.23%、增重42.44%;套餐施肥B与常规施肥C相比SPAD有显著差异,SPAD值提高6.83%.莲花白结球期,套餐施肥A与常规施肥C相比,地上鲜重、包心鲜重,分别增重 71.25%、73.66%;套餐施肥B与常规施肥C相比,地上鲜重、包心鲜重分别增重 67.25%、56.42%.莲花白成熟期,套餐施肥A Vc、可溶性糖、地上鲜重、包心鲜重比常规施肥C分别增多8.28 mg/kg、2.21 mg/kg,分别增重 28.97%、54.90%;套餐施肥B Vc、可溶性糖、地上鲜重、包心鲜重比常规施肥C分别增多2.41 mg/kg、0.98 mg/kg,分别增重20.56%、39.22%.
以河南省粮食主产区夏玉米为试验作物,开展不同含量腐植酸控释掺混肥对夏玉米产量及土壤肥力的影响研究.结果表明:腐植酸控释掺混肥能有效降低玉米秃尖,对玉米穗长、亩穗数的影响无差异,对穗粒数、百粒重影响差异显著.与普通氮磷钾掺混肥(CK)相比,腐植酸控释掺混肥(T1～T4)处理玉米穗粒数增加1.66%～12.03%,百粒重提高3.43%～9.05%,单产提高6.76%～24.16%,增收62.6～263.4元/667 m2.从区域表现来看,豫中褐土区、豫东砂姜黑土区施用含7%腐植酸控释掺混肥经济效益最高,豫南砂姜黑土区、豫北潮土区含5%腐植酸控释掺混肥经济效益最高;同时显著改善了土壤理化性状,持续提升耕地质量.从多年多点试验表现来看,腐植酸控释掺混肥均表现出良好的增产、创高产效应,且在不同区域、不同土壤类型、不同玉米品种上表现高度一致.说明腐植酸控释掺混肥具有广泛适宜性和创高产性,为化肥减量增效和耕地质量提升提供了技术产业化路径.
第一条为了规范推荐性国家标准采信团体标准,拓宽推荐性国家标准供给渠道,促进团体标准创新成果广泛应用,制定本规定. 第二条本规定所称推荐性国家标准采信团体标准,是指将符合本规定要求的团体标准,经过一定程序,转化制定为推荐性国家标准的活动.
腐植酸是土壤养分的重要组成部分,对改善土壤性质有显著影响,不仅可以增强土壤肥力,促进作物生长发育,提高作物产量,而且对环境友好.近年来,腐植酸广泛应用于农、林、牧、石油、化工、建材、医药卫生、环保等各个领域.国内外学者对腐植酸应用基础进行了大量研究并取得系列成果.本文主要对腐植酸在农业方面的研究进展进行了总结,分析了腐植酸的种类结构对土壤性质及作物生长影响的研究进展,并对腐植酸的应用前景做出展望.
