首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 234 毫秒
1.
生物质炭(biochar,BC)施用具有改良土壤、提高作物产量等效应。本文探究了生菜产量、品质和土壤性质等对化肥氮(N)减施和生物质炭施用1年后的响应,以期为珠三角地区露地蔬菜生产中化肥合理减量和生物质炭科学施用提供依据。通过在佛山市三水区开展田间小区试验,观测了常规施氮(N100%)、减氮20%(N80%)、减氮40%(N60%)、减氮40%+生物质炭10 t/hm2(N60%+BC10)和减氮40%+生物质炭20 t/hm2(N60%+BC20)处理下生菜产量、品质、叶片SPAD值及土壤养分等指标的变化。结果表明:(1)较N100%处理,N60%处理生菜产量显著降低13.5%。减氮40%条件下,配施10~20 t/hm2生物质炭可提高生菜产量9.5%~22.7%,与N100%处理产量相当,说明生物质炭施用对生菜产量具有显著提升效果。(2)氮肥减量和生物质炭施用对生菜单株鲜重、直径和水分含量等均无显著影响,而对叶片SPAD值在不同生育期有不同影响。减氮条件下施用生物质炭处理生菜的氮和磷吸收量提高,是其增产机理之一。(3...  相似文献   

2.
土壤反硝化对磺胺嘧啶及抗性基因消减的影响   总被引:1,自引:0,他引:1  
农田土壤中抗生素及抗性基因的复合污染已给生态环境安全和人体健康带来了全新隐患。针对厌氧条件下,反硝化作用过程对土壤抗生素乃至抗性基因消减影响的研究一直相对较少。因而,本研究采集牛粪堆积池塘周边底层农田土壤作为目标污染土壤,重点研究反硝化作用过程对土壤磺胺嘧啶及抗性基因消减动态的影响。结果表明:相较于原始污染土壤处理(T1),添加了NO_3~–-N的处理(T2)可以显著强化土壤和水相中反硝化速率,提升N_2O的产气速率,促进土壤中磺胺嘧啶浓度和抗性基因丰度的快速降低;同时发现土壤反硝化基因(nir K、nir S和nos Z)与磺胺类抗性基因(sul Ⅰ和sul Ⅱ)呈显著负相关(P0.05),说明当NO_3~–-N底物越充足,土壤反硝化细菌活性往往被激活,其反硝化功能基因表达就越活跃,土壤反硝化作用过程就越强烈,从而反馈作用促进磺胺嘧啶抗生素的厌氧消减,进而有助于sul系列抗性基因丰度的显著衰减;同时通过高通量测序技术及对反硝化细菌的分离筛选后,发现变形菌门(Proteobacteria)赖氨酸芽胞杆菌属(Lysinibacillus)的细菌是土壤厌氧反应前后的主导优势菌群,对于强化反硝化过程和促进磺胺嘧啶及sul抗性基因的消减发挥了潜在的积极作用。本研究结果可为探明土壤中抗生素的厌氧消减过程和缓解抗性基因的扩散传播提供新颖的认知基础。  相似文献   

3.
【目的】我国温室种植蔬菜迅速发展,温室种植中肥料利用率低及蔬菜硝酸盐积累等问题日益突出。同时,我国城市化快速发展,城市园林废弃物日益增多,这些木质废弃物的处理也成为城市可持续发展的挑战。本文采用城市园林废弃物制成的生物质炭用于温室栽培生产,分析其对温室蔬菜产量和品质以及养分保持的影响,从而探索一种为绿色环保的现代城市农业服务的技术。【方法】本研究采用温室盆栽试验方法,以小白菜为研究对象,设置5个生物质炭添加水平。 C0 (0 g/kg, CK)、 C1(20 g/kg)、 C2(40 g/kg)、 C3(60 g/kg)和C4(80 g/kg)。研究生物质炭对小白菜产量、 植株硝酸盐含量、 土壤氮素含量与形态以及氮素保持效应的影响。【结果】与对照相比,添加不同比例的生物质炭均显著提高小白菜产量,其中,C3和C4处理下增产幅度达到75%,生物质炭添加量与产量呈显著正相关关系;生物质炭对小白菜植株地上部和地下部的影响并不一致,其中收获指数显著增加,提高幅度在2.5%~9.5%之间,有随着生物质炭用量增加而增加的趋势;对照处理小白菜地上部硝酸盐含量达504 mg/kg,各处理植株硝酸盐含量介于161~256 mg/kg之间,显著降低50%以上,特别是C1处理降低硝酸盐含量的幅度达到68%,而不同生物质炭添加量之间植株硝酸盐含量差异不显著;生物质炭的添加增加了土壤中总氮素的含量,氮素损失率由不施炭处理的5.6%降低到了3.3%以下,显著降低了42%,同时土壤氮素生产率较对照提高幅度大于35%;与C0相比较,生物质炭添加显著降低了土壤NO-3-N的积累,降低幅度在60%以上,生物质炭用量在4%左右时降低作用最大,达到80%,同时土壤NH+4-N在生物质炭添加下降低了77%,生物质炭对降低土壤中铵态氮和硝态氮的累积作用并不与其用量呈正相关,铵硝比随着生物质炭添加量而呈下降的趋势;同时从研究结果看,产量与土壤NH+4-N和NO-3-N含量呈负相关关系,与土壤全氮呈正相关关系,而蔬菜植株硝酸盐含量与土壤NH+4-N和NO-3-N含量具有相关性,但与土壤全氮含量相关性不显著。【结论】温室大棚栽培小白菜的土壤中, 加入不同量的生物质炭能显著提高小白菜产量,同时降低小白菜植株的硝酸盐含量,添加量在2%时效果最好;土壤硝态氮和铵态氮积累随生物质炭施入而降低;生物质炭显著降低氮素损失率而提高氮素生产率。本研究得出生物质炭通过降低损失、 吸持更多氮素而提高了氮素的持续供应,在增产的同时降低了蔬菜硝酸盐积累,提高了品质。因此,在温室大棚蔬菜生产的土壤中添加一定量生物质炭(本试验下添加2%~4%)可以达到高产和优质。  相似文献   

4.
选择长期种植黄瓜并发生根结线虫病的大棚,设计生物质炭施用量为0(C0)、24(C1)、48(C2)t/hm~2的田间试验,研究生物质炭对黄瓜生长、品质以及根结线虫病的影响。结果表明:生物质炭显著提高了土壤有机质、全氮、铵态氮、速效钾含量和pH,同时降低土壤体积质量11.0%以上,C2处理黄瓜根系生物量较C0显著增加了56.9%。与C0相比,C2处理显著增加黄瓜可溶性糖和有机酸含量25.0%和17.6%,C1处理显著降低黄瓜硝酸盐含量25.5%。C2处理黄瓜根系单株卵块数比C0增加了3.8倍。施用生物质炭对黄瓜产量没有显著影响。研究结果说明,蔬菜大棚土壤中施用生物质炭可改善土壤理化性状,提高黄瓜品质,但有增加根系卵块数的趋势。由于生物质炭与土壤、作物的相互作用会随时间的变化而改变,因此,生物质炭对大棚黄瓜品质和根结线虫病的影响效应需进一步长期观测。  相似文献   

5.
为探索不同有机肥对植烟土壤氮素矿化及土壤微生态的影响。在等氮(100 mg/kg)投入和30℃条件下对施入不同有机肥(植物源有机肥、芝麻饼肥、生物质炭有机肥)的土壤进行室内培养,分析不同时期土壤NO3–-N和NH4+-N含量、土壤酶活性及细菌群落多样性的变化。结果表明:施用不同有机肥均可提高土壤矿质氮含量,在培养前期以饼肥矿化量最高,矿化速率最快,而后期为生物质炭有机肥处理的氮素矿化量、矿化速率高于其他处理;施用生物质炭有机肥、植物源有机肥均可显著提高土壤脲酶、硝酸还原酶活性,芝麻饼肥对蛋白酶、蔗糖酶活性有显著的提升作用;相较不施有机肥处理,添加不同有机肥的土壤细菌多样性明显提升。优势菌门为变形菌门、酸杆菌门、拟杆菌门、浮霉菌门,优势菌属为Sphingomonas、RB41,Sphingomonas在不施有机肥处理中最高,RB41在生物质炭有机肥处理中最高。Sphingomonas与蔗糖酶活性呈正相关关系,与脲酶、硝酸还原酶均呈负相关关系;PCA分析显示,生物质炭有机肥处理的细菌群落结构与其他处理相比差异较大。施用芝麻饼肥有利于促进早期氮素矿化,提高矿化量,而生物质炭有机肥后期矿化量较...  相似文献   

6.
设置五种有机物料(水稻秸秆、玉米秸秆、小麦秸秆、稻壳和竹子)制备的生物质炭改良酸性土壤的田间试验,以不施生物质炭为对照(CK),运用电化学阻抗谱法研究不同生物质炭对酸性土壤电化学特性的影响。结果表明,不同处理的等效电路拓扑结构一致,但电路元器件参数存在差异;Nyquist图表现为高频区圆弧和低频区斜线的形式,各曲线与横坐标的截距对应等效电路中土壤多孔层电阻R2,圆弧半径对应电荷转移电阻R3,Bode图中不同生物质炭改良酸性土壤的阻抗模值随频率增大整体呈减小趋势。采用Z-view软件拟合出等效电路图可知,不同生物质炭改良酸性土壤对各元件参数值的影响为孔隙溶液电阻R1减小,土壤多孔层电阻R2增大和电容C1减小,电荷转移电阻R3和扩散阻抗系数W增大,以及CPE-T值减小。其中,R1的减小表示土壤水溶性盐含量和CEC的增加;R2增大和C1减小表示土壤介质体系的导电能力降低;R3、W和CPE-T值的变化表示土壤体系的转移电荷能力降低和整体稳定性的提高。拟合参数值在一定程度上揭示了改良酸化对土壤pH和可溶性盐基离子含量的影响,同时丰富了电化学阻抗谱的研究范围。  相似文献   

7.
生物质炭对土壤养分及设施蔬菜产量与品质的影响   总被引:6,自引:0,他引:6  
【目的】 我国是世界最大的温室蔬菜生产国,但随着种植年限的增长,温室设施栽培中土壤次生盐渍化、蔬菜品质降低及作物减产等问题日益突出。本文以生物质炭为土壤改良剂施用于温室大棚蔬菜栽培中,分析其对蔬菜生长和土壤养分供应的影响,从而探索一种绿色可持续发展的设施农业生产方式。同时,也为生物质炭在大棚蔬菜栽培中的合理施用提供依据。 【方法】 采用田间试验方法,以温室大棚西芹和茄子为研究对象,试验共设5个生物质炭施用水平,分别为0、20、40、80和160 t/hm2,依次记为B0、B20、B40、B80和B160处理。分析了蔬菜产量、西芹植株硝酸盐含量、茄子维生素C含量及过氧化氢酶活性和土壤养分含量。 【结果】 与B0相比,B20和B160处理能够提高西芹产量,增产幅度分别达31.6%和30.3%,B40和B80处理对西芹产量无显著影响;B20处理对西芹硝酸盐含量无显著影响,B40、B80和B160处理显著降低了西芹植株硝酸盐含量,降低幅度分别达37.0%、37.2%和49.1%,但处理间差异不显著。施用生物质炭对茄子产量、茄子维生素C含量与过氧化氢酶活性影响不显著,当施用量达160 t/hm2时,反而抑制了茄子果实氮、磷养分积累。与B0相比,施用生物质炭有效增加了西芹收获后土壤速效钾含量,其中,B80和B160处理增加幅度分别为95.8%和196.2%;茄子收获后,B160处理土壤速效钾增加幅度达165.5%。施用生物质炭对土壤有效磷含量无显著影响,对土壤碱解氮含量的影响较为复杂,即对西芹收获后土壤碱解氮含量影响不显著,却降低了茄子收获后土壤碱解氮含量,其中,B40、B80和B160处理降低幅度分别达11.7%、10.0%和20.3%。经济效益分析表明,B20处理温室大棚经济收益最高,与B0相比纯收入增加9.4%;随着生物质炭施用量增多,肥料投入成本加大,B160处理收益最低。 【结论】 在本试验条件下,生物质炭用量为20 t/hm2时增产效果最好,且温室大棚收益最高,而对蔬菜品质无显著影响;当其施用量为40 t/hm2时能显著降低西芹硝酸盐含量。因此,需要继续研究生物质炭施用量在20~40 t/hm2之间的最适量,达到既能提高蔬菜产量又能改善品质的目的。   相似文献   

8.
  目的  为探明生菜吸收富集镉的能力对生物炭与叶面硒肥的响应程度,抑制有毒有害元素镉的吸收。  方法  通过盆栽试验,以生菜为研究对象,在镉污染土壤中添加生物炭,并在生菜叶片上喷硒处理,探索了生物炭与叶面喷硒的联合施用对镉污染土壤理化指标(pH和有机碳)和土壤不同形态镉含量以及对生菜镉吸收累积的影响。  结果  ① 土壤中添加生物炭与叶面硒肥都可以有效降低生菜可食部镉含量,其中喷施低浓度硒的效果更好。当生物炭添加量为30 g kg?1,叶面喷硒浓度为1 mg L?1时,生菜地上部镉含量由0.314 mg kg?1降至0.049 mg kg?1,低于国家食品安全标准(GB 2762—2017)中规定的叶菜类镉限量值0.20 mg kg?1。② 镉胁迫下,添加生物炭与叶面硒肥的交互作用对生菜镉含量和镉富集与转运能力均产生了显著性的影响,相对于生菜根部镉含量,添加生物炭的效应高于叶面硒肥的效应,而对于地上部镉含量,叶面硒肥的效应高于添加生物炭的效应。③ 生物炭添加可通过改善土壤pH和有机碳含量降低酸可提取态、可还原态、可氧化态镉的比例,增加残渣态镉的比例,从而有效地降低生菜对土壤中镉的吸收累积,减少生菜中镉含量。  结论  综合来看,生物炭与叶面硒肥联合施用可以降低生菜镉含量,其效果明显高于两者单独施用的效果,为无公害蔬菜的种植提供理论指导。  相似文献   

9.
为探明生物质炭与氮肥配施对土壤中氮素循环和烤烟氮素利用的影响,采用盆栽试验,设置4个处理:5 g/盆纯氮(CK),5 g/盆纯氮+100 g/盆生物质炭(T1),3.5 g/盆纯氮+100 g/盆生物质炭(T2),2 g/盆纯氮+100 g/盆生物质炭(T3),利用~(15)N标记的氮肥,测定生物质炭与氮肥配施条件下烤烟生长不同时期土壤中~(15)N的残留量、不同形态氮素的含量、土壤微生物生物量氮含量和移栽后90 d烤烟烟叶对不同氮源氮素的累积量。试验结果表明:相同施氮量时,生物质炭的施用可以提高土壤中~(15)N残留量、土壤无机氮、碱解氮、微生物量氮的含量和叶片对氮素的累积量。生物质炭与氮肥配施时提高了肥料氮在烟叶中的占比,使~(15)N利用率提高了25.4%~63.3%。与对照相比,T2处理植烟土壤中NH_4~+-N、NO_3~–-N、碱解氮在烤烟移栽后75 d比对照分别提高了17.3%、8.0%、7.2%,碱解氮和微生物生物量氮的含量在烤烟移栽后90 d也高于对照。在本试验条件下,生物质炭与氮肥配施对土壤氮素的影响是显著的,施用生物质炭时减少30%氮肥用量是可行的。  相似文献   

10.
杉木凋落物及其生物炭对土壤微生物群落结构的影响   总被引:6,自引:0,他引:6  
以福建建瓯万木林自然保护区内的杉木人工林土壤为研究对象,设置单独添加生物炭、单独添加凋落物以及混合添加凋落物和生物炭处理,进行一年的室内培养实验,研究不同添加物处理对土壤性质及微生物群落结构的影响。结果表明:与对照(S)相比,单独添加凋落物与混合添加凋落物和生物炭均使土壤磷脂脂肪酸(PLFA)总量、真菌丰度以及真菌/细菌比值显著增加;单独添加生物炭与混合添加凋落物和生物炭均使革兰氏阳性细菌/革兰氏阴性细菌比值显著增加。混合添加凋落物和生物炭处理的放线菌丰度显著高于单独添加凋落物处理的。主成分分析表明,不同添加物处理的土壤微生物群落结构存在显著差异;典范对应分析表明,不同添加物处理通过改变土壤p H、全碳、全氮、C/N、可溶性有机碳(DOC)和可溶性有机氮(DON)等性质,进而影响土壤微生物群落结构。  相似文献   

11.
铜和强力霉素复合污染对土壤微生物与酶活性的影响   总被引:1,自引:1,他引:0  
当前土壤环境中重金属和抗生素的广泛共存及二者复合存在所诱导出的细菌抗性,与单一物质的污染相比,均能够加剧对土壤质量和作物安全的破坏。在在实验室模拟培养条件下,向土壤中加入不同浓度的重金属(铜)和抗生素(强力霉素),探讨抗生素和重金属复合污染对土壤微生物呼吸、脲酶、蔗糖酶和过氧化氢酶活性和四环素抗性基因的丰度等土壤微生物指标的影响。结果显示,在整个培养期(30 d)内,铜和强力霉素单一及复合污染均会显著抑制土壤微生物呼吸强度,对脲酶活性主要表现为促进作用,对蔗糖酶、过氧化氢酶活性主要为抑制作用,对过氧化氢酶活性的抑制强度明显大于蔗糖酶。综合而言,铜和强力霉素的复合污染相对于单一污染对上述微生物指标的影响较大,强力霉素的加入可以促进铜对微生物呼吸或酶活性的初始影响。此外,该研究还表明添加为400mg·kg~(–1)铜可以提高强力霉素在土壤培养中后期诱导的抗性基因相对丰度的能力水平。本研究从微生物角度定量探讨铜与强力霉素单一及复合污染对土壤微生物指标的影响程度,以期为重金属与抗生素协同污染的土壤构建微生物预警体系,并为土壤修复和风险评估工作提供理论依据。  相似文献   

12.
Biochar added to agricultural soils may sequester carbon and improve physico-chemical conditions for crop growth, due to effects such as increased water and nutrient retention in the root zone. The effects of biochar on soil microbiological properties are less certain. We addressed the effects of wood-based biochar on soil respiration, water contents, potential ammonia oxidation (PAO), arylsulfatase activity (ASA), and crop yields at two temperate sandy loam soils under realistic field conditions. In situ soil respiration, PAO, and ASA were not significantly different in quadruplicate field plots with or without biochar (20 Mg ha?1); however, in the same plots, volumetric water contents increased by 7.5 % due to biochar (P?=?0.007). Crop yields (oat) were not significantly different in the first year after biochar application, but in the second year, total yields of spring barley increased by 11 % (P??1, applied during two consecutive years, substantiated that biochar was not inhibitory to PAO and ASA as reference plots consistently showed lowest activities. For PAO, it was found that soil pH, rather than biochar rates, was a driving environmental variable. For ASA, the methodological approach was challenged by product sorption, but results did not suggest that biochar significantly stimulated the enzyme activity. Crop yields of maize in field experiments with 10–100 Mg biochar ha?1 were unaffected by biochar except for a negative effect of the highest annual rates of 50 Mg ha?1 in the first year after application. In conclusion, the present wood-based biochar poorly affected the measured microbial processes and generally resulted in similar crop yields in reference and biochar-amended soil plots.  相似文献   

13.
Application of biochar to soil has increased considerably during recent years because of its effectiveness as a soil amendment causing beneficial effects on soil health. However, the effects have been reported to vary and depend upon types of feedstock and pyrolysis conditions during biochar production. Therefore, characterization of biochar is extremely important for its efficient utilization as a soil amendment. In the present study, biochar was prepared from agro-industrial by-products (rice husk and sugarcane bagasse) and weeds (Parthenium and Lantana) under similar pyrolysis conditions. Lantana biochar (LBC) showed the highest pH (10.4) while the lowest value (8.5) being recorded in rice husk biochar (RHBC). The energy-dispersive X-ray spectroscopy (EDS) analysis indicated that LBC and Parthenium biochar (PBC) were superior with respect to potassium (K) content than sugarcane bagasse biochar (SBBC) and RHBC. The Fourier-Transform Infrared Spectroscopy (FTIR) study exhibited the existence of different functional groups in biochar. All the biochar treated soils showed significantly higher microbial activities with different degrees. Application of LBC and PBC at 4.50 g kg?1 soil significantly increased K availability in soil. Lantana biochar and PBC amended the soil at 9 g kg?1 significantly increased the soil pH thus makes these biochar as potential liming materials.  相似文献   

14.
研究生物炭和丛枝菌根(arbuscularmycorrhizal,AM)真菌对连作辣椒生长和土壤养分的影响,可为辣椒连作土壤改良和新型肥料的开发提供理论依据。采用温室盆栽试验,设置4个生物炭添加水平(0、1%、2%、3%), 2个接菌水平[接菌(+AM)和不接菌(-AM)]。辣椒生长60 d后收获并测定其生理指标、土壤酶活性及土壤养分含量。结果表明,施加生物炭和接种AM真菌处理促进了连作辣椒的生长,提高了辣椒叶片净光合速率、蒸腾速率、气孔导度和叶绿素含量。接种AM真菌对辣椒的促生效果弱于生物炭,而生物炭和AM真菌配施的促生效果最佳。接种AM真菌促进辣椒对P吸收的效果优于生物炭;但对于K吸收来说,施加生物炭的效果优于接菌。生物炭(3%)和AM真菌配施条件下,辣椒根部N、P、K含量分别较对照(0生物炭和-AM处理)显著提高74.04%、106.42%和78.82%。生物炭(3%)与AM真菌配施处理菌根侵染效果最佳,侵染率高达58.96%,较0生物炭+AM处理提高41.59%。土壤pH随生物炭添加量的增加呈增加趋势,但差异不显著。土壤脲酶、蔗糖酶活性随生物炭添加量的增加呈增加趋势,且差异显著,接种AM真菌处理对其影响不显著。土壤速效钾、有效磷、有机质含量随生物炭添加量的增加而增加,接种AM真菌对土壤有机质含量、阳离子交换量(CEC)无显著影响。土壤速效钾、有效磷、碱解氮含量均在生物炭(3%)和AM真菌配施条件下达最大。与单一处理相比,生物炭和AM真菌配施在促进连作辣椒生长、改善连作土壤养分方面具有显著的协同增效作用,尤其是3%生物炭与AM真菌配施条件下效果最佳。  相似文献   

15.
Tetracycline(TC)and tetracycline resistance genes(TRGs)in plant edible tissues pose a potential risk to the environment and then to human health.This study used a pot experiment to investigate the effects of different remediation substances(worm castings,fungal chaff,microbial inoculum,and biochar)on the physiological characteristics of maize and the residues of TC and TRGs in the soil-maize system under TC stress.The results showed that TC significantly inhibited growth,disrupted the antioxidant defense system balance,and increased proline and malondialdehyde contents of maize plants.Tetracycline residue contents were significantly higher in root than in shoot,and followed the order root>stem-leaf>grain,which was consistent with the distribution of bioconcentration factors in the different organs of maize plants.The TC residue content in the soil under different treatments was 0.013–1.341 mg kg-1.The relative abundances of different antibiotic resistance genes in the soil-maize system varied greatly,and in maize plants followed the order intI1>tetW>tetG>tet B>tetM>tetX>tetO.In the soil,tetX had the highest relative abundance,followed by tetG and tetW.A redundancy analysis(RDA)showed that TC was positively correlated with TRGs.The addition of different remediation substances alleviated the toxicity of TC on maize physiological characteristics and reduced the TC and TRG residues in the soil-maize system,with biochar being the best remediation substance.These results provide new insights into the effect of biochar on the migration of TC and TRGs from soil to plants.  相似文献   

16.
Our contemporary society is struggling with soil degradation due to overuse and climate change. Pre‐Columbian people left behind sustainably fertile soils rich in organic matter and nutrients well known as terra preta (de Indio) by adding charred residues (biochar) together with organic and inorganic wastes such as excrements and household garbage being a model for sustainable agriculture today. This is the reason why new studies on biochar effects on ecosystem services rapidly emerge. Beneficial effects of biochar amendment on plant growth, soil nutrient content, and C storage were repeatedly observed although a number of negative effects were reported, too. In addition, there is no consensus on benefits of biochar when combined with fertilizers. Therefore, the objective of this study was to test whether biochar effects on soil quality and plant growth could be improved by addition of mineral and organic fertilizers. For this purpose, two growth periods of oat (Avena sativa L.) were studied under tropical conditions (26°C and 2600 mm annual rainfall) on an infertile sandy soil in the greenhouse in fivefold replication. Treatments comprised control (only water), mineral fertilizer (111.5 kg N ha–1, 111.5 kg P ha–1, and 82.9 kg K ha–1), compost (5% by weight), biochar (5% by weight), and combinations of biochar (5% by weight) plus mineral fertilizer (111.5 kg N ha–1, 111.5 kg P ha–1, and 82.9 kg K ha–1), and biochar (2.5% by weight) plus compost (2.5% by weight). Pure compost application showed highest yield during the two growth periods, followed by the biochar + compost mixture. biochar addition to mineral fertilizer significantly increased plant growth compared to mineral fertilizer alone. During the second growth period, plant yields were significantly smaller compared to the first growth period. biochar and compost additions significantly increased total organic C content during the two growth periods. Cation‐exchange capacity (CEC) could not be increased upon biochar addition while base saturation (BS) was significantly increased due to ash addition with biochar. On the other hand, compost addition significantly increased CEC. Biochar addition significantly increased soil pH but pH value was generally lower during the second growth period probably due to leaching of base cations. Biochar addition did not reduce ammonium, nitrate, and phosphate leaching during the experiment but it reduced nitrification. The overall plant growth and soil fertility decreased in the order compost > biochar + compost > mineral fertilizer + biochar > mineral fertilizer > control. Further experiments should optimize biochar–organic fertilizer systems.  相似文献   

17.
It has been demonstrated that soil amended with biochar, designed specifically for use as a soil conditioner, results in changes to the microbial populations that reside therein. These changes have been reflected in studies measuring variations in microbial activity, biomass, and community structure. Despite these studies, very few experiments have been performed examining microbial genes involved in nutrient cycling processes. Given the paucity of research in this area, we designed a 6 month study in a Portneuf subsoil treated with three levels (1%, 2%, and 10% w/w ratio) of a biochar pyrolyzed from switchgrass (Panicum virgatum) at 350 °C and steam activated at 800 °C to measure the abundances of five genes involved in N cycling. Gene abundances were measured using qPCR, with relative abundances of these genes calculated based on measurement of the 16S rRNA gene. At the end of the 6 month study, all measured genes showed significantly greater abundances in biochar amended treatments as compared to the control. In soil amended with 10% biochar, genes involved in nitrogen fixation (nifH), and denitrification (nirS), showed significantly increased relative abundances. Lastly, gene abundances and relative abundances correlated with soil characteristics, in particular NO3-N, % N and % C. These results confirm that activated switchgrass-derived biochar, designed for use as a soil conditioner, has an impact on the treated soils microbial communities. We therefore suggest that future use of biochar as a soil management practice should take into account not only changes to the soil's physiochemical properties, but its biological properties as well.  相似文献   

18.
Aims : The aim of this study was to explore interactive effects between quality (types) and quantity (application rates) of biochar as well as of arbuscular mycorrhiza (AM) symbiosis on the growth of potato plants. Methods : A low P sandy loam soil was amended with 0%, 1.5%, or 2.5% (w/w) of either of 4 types of biochar, which were produced from wheat straw pellets (WSP) or miscanthus straw pellets (MSP) pyrolyzed at temperatures of either 550°C or 700°C. Potato plants grown in pots containing the soils or soil biochar mixture were inoculated with or without AM fungus (AMF), Rhizophagus irregularis. The experiment was carried out under fully irrigated semi‐field conditions and plants were harvested 101 days after planting. Results : Application of high temperature biochar decreased growth, biomass and tuber yield of potato plants, while the low temperature biochar had a similar effect on yield as plants grown without biochar amendment. Total biomass of potato plants were decreased with the increasing rate of biochar. Arbuscular mycorrhizal fungus inoculation stimulated the growth of potato plants in all organs, increased tuber biomass significantly in 1.5% MSP700 amended plants, and to a lesser degree for WSP700, MSP550, and WSP550. In addition, plant biomass gain was linearly related to N, P, and K uptake, the ratio of P to N in the leaf of plants indicated that all treatments were mainly P‐limited. A multiple linear regression using P uptake and biochar rate as independent variables explained 91% of the variation in total biomass. The single effect of AMF inoculation, type and rate of biochar affected plant N, P and K uptake similarly. While AMF inoculation significantly increased P uptake in potato plants grown in soil with WSP700 or MSP700 despite of the rate of biochar. In general, application of biochar significantly increased AMF root colonization of potato plants. Conclusions : The application of MSP550 at 1.5% combined with AMF stimulated growth of potato the most. Furthermore, the results indicated that the interactive effect of AMF inoculation, biochar type and application rate on potato growth to a large extent could be explained by effects on plant nutrient uptake.  相似文献   

19.
Direct use of poultry manure on agricultural lands may cause environmental concerns, so there is a need to establish the suitability of the application of biochar derived from poultry manure for calcareous soil chemical properties and plant growth. The purpose of this study was to evaluate the effects of processed poultry manure (0, 5, 10 and 20 g/kg) and its biochar (0, 2.5, 5, 10 and 20 g/kg) on soil chemical properties of a calcareous soil and growth of bean (Phaseolus vulgaris) and maize (Zea mays) plants. In the incubation experiment, both processed poultry manure (PPM) and biochar decreased pH and the concentration of plant‐available Fe of soil but increased plant‐available P, Zn, Cu and Mn concentrations. PPM and biochar increased the concentrations of exchangeable cations (K, Ca and Mg) in soil. PPM and biochar applications increased the growth of maize and bean plants. PPM and biochar resulted in increased concentrations of N, P, K, Ca, Fe, Zn, Cu and Mn in bean plants. In maize plants, PPM and biochar applications increased the N, P, K, Zn, Cu and Mn but decreased the Ca and Mg concentrations. Results of this study reveal that poultry manure biochar can be used effectively for agricultural purposes.  相似文献   

20.
Pot experiment was conducted under axenic conditions in a growth chamber with 14 h photoperiod at 22/26°C to evaluate the role of biochar, phosphate-solubilizing rhizobacteria (Pseudomonas sp.), and chemical fertilizer under induced salt stress (150 mM sodium chloride (NaCl)). Factorial randomized complete plot designs with three replications were used. Biochar and fertilizer were mixed in soil (5:1) while Pseudomonas sp. was applied as seed soaking. Salt stress applied at 3 leaf stage significantly reduced (27%) soil moisture and increased electrolyte leakage, Na and potassium (K) uptake, proline, and antioxidant enzymes. Biochar and Pseudomonas sp. decreased the sodium by 24% and 50%, respectively, and increased proline, soil moisture content, and peroxidase (POD) activity. Fertilizer treatment increased the electrolyte leakage by 73%. The effect of fertilizer was 3–4× higher for proline and POD activity in combined treatment with biochar and Pseudomonas. The fertilizer effect can be augmented by the application of Pseudomonas sp. and biochar to alleviate salt stress.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号