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1.
不同种植年限设施菜地土壤有机质组成与结构变化 总被引：1，自引：1，他引：0
《土壤通报》2016,(6):1386-1392
试验采集不同种植年限设施菜地土壤样品,测定土壤有机质(SOM)、可溶性有机碳(DOC)、胡敏酸(HA)、富里酸(FA)、微生物量碳(MBC)、微生物商(C_(mic)-to-C_(org))、C矿化和E4/E6值等指标,结合傅立叶变换红外光谱技术解析不同种植年限土壤有机质组成与结构变化的规律。结果显示,随着种植年限的增加,SOM、DOC、HA、HA/FA、MBC、C_(mic)-to-C_(org)、E4/E6值、C矿化率和CO_2释放速率均出现明显下降趋势,其中MBC、C_(mic)-to-C_(org)、C矿化率、CO_2释放速率和HA/FA在种植6 a时下降最明显,之后变化缓慢。与露天农田土壤(CK)相比,设施菜地呈现较高的SOM、DOC、Humus、HA、FA、HA/FA和E4/E6。胡敏酸红外光谱图谱显示设施菜地种植20 a处理土壤芳构化程度高,结构稳定,难以降解,其他三种种植年限(3 a、6 a和10 a)的芳构化程度相对较低,脂肪族成分相对较高。综上可知,设施菜地土壤有机质组成与结构随着种植年限的增加具有规律性变化,结果加深了对设施菜地土壤有机质演变规律的认知。 相似文献
2.
秸秆还田条件下内陆盐碱土腐殖质的动态变化 总被引：1，自引：0，他引：1
采用室内培养试验的方法,研究了秸秆加入条件下内陆盐碱土的腐殖质及其组分(胡敏酸、富里酸)的动态变化。结果表明,在秸秆腐解过程中,盐碱土腐殖质、富里酸、胡敏酸含量均呈现持续上升趋势,分别平均增加了112.5%,269.54%和92.9%富里酸的含量明显高于胡敏酸的含量,是胡敏酸含量的约3~10倍。土壤的HA/FA(腐殖酸/富里酸)呈现出先增长后降低的趋势,并且在90d时达到平均最高值(0.283)。尿素添加量7.2g的处理土壤腐殖质含量在0.19%~0.38%,该处理秸秆分解的速率最快。土壤腐殖质和富里酸随着尿素含量梯度的增加呈现先上升,后下降,再上升的趋势,且分别平均增加了46.7%和55.3%胡敏酸的变化趋势与腐殖质相反,平均减少了14.3%HA/FA呈下降趋势,但下降趋势不明显。 相似文献
3.
基于荧光分析的不同有机碳水平水稻土添加外源有机物培养对DOC的影响 总被引：2，自引：0，他引：2
以江西省红壤研究所内的水稻土有机肥长期定位试验(始于1981年)为研究对象,基于三维荧光技术,在室内培养条件下,研究外源有机物(葡萄糖和秸秆,分别代表易分解和难降解碳)对不同碳水平水稻土可溶性有机碳含量与结构的影响。结果表明:添加葡萄糖对高碳和低碳水稻土可溶性有机碳(DOC)含量均无显著影响(p0.05),但可以促进DOC结构中类溶性微生物代谢产物的增加与类胡敏酸类富里酸的减少。添加秸秆则对高碳和低碳水稻土DOC有不同的影响:低碳土壤中,在培养末期(60d),添加秸秆处理的DOC含量显著提高(p0.05),而高碳土壤处理则无显著变化。在DOC结构方面,秸秆可以促进低碳土壤中类蛋白物质转化为更稳定的类胡敏酸和类富里酸物质;对于高碳土壤,则可以促进类溶性微生物代谢产物的积累,促进类胡敏酸与类富里酸的分解利用。低碳土壤DOC含量相对稳定,结构受外源有机碳影响较大;高碳土壤DOC结构相对稳定,但含量变化较大。 相似文献
4.
不同恢复阶段人工沙棘林土壤腐殖质组成及性质 总被引：3，自引：1，他引：2
以陇东黄土高原沟壑区人工沙棘林根际土壤为研究对象,研究了不同恢复阶段近熟期沙棘林土壤的腐殖质组成、结合形态及胡敏酸的光学性质。结果表明,不同恢复年限人工沙棘林下土壤腐殖质各组分有机碳含量为:胡敏素(HM)胡敏酸(HA)富里酸(FA);PQ值(可提取腐殖质中HA的比例)表现为:CK7a10a15a,且不同恢复年限各层土壤的PQ均大于52%;E4/E6和ΔlgK(色调系数)的值:15a10aCK7a;RF值(相对色度)与E4/E6和ΔlgK的变化趋势相同,即15a10a7aCK。恢复15a后,各层土壤有机碳的腐殖化程度比10,7a和CK显著降低,说明随着恢复年限的增加,土壤的腐殖化程度趋向简单,土壤胡敏酸的氧化稳定性下降,且不利于土壤的肥力发展。因此,在利用人工沙棘林进行水土保持和恢复提高土壤综合肥力超过15a时,应及时更新。 相似文献
5.
陕西省几种主要土壤胡敏酸能态及热分解特性的研究 总被引：8，自引：0，他引：8
氧弹量热计法测定不同土壤胡敏酸的热值(能态)表明,不同土壤胡敏酸具有不同的能态.土壤胡敏酸总能态高低与土壤有机质、全氮、胡敏酸含量呈显著正相关.DTA和TG法测定不同土壤胡敏酸的热分解特性表明,不同土壤胡敏酸的DTA、DTG曲线都有共同相似的热效应峰和失重峰.同时表明,与之相对应的焓变(△H)、重量损失百分数(W%),最大重量损失率-(dW/dT)m、活化能(E)、比速率常数(K0)都有一定差异.红外光谱测定表明,不同温度下,不同胡敏酸热解温度上升到324-338℃时,主要是非核部分脂肪族侧链及氢链结合OH的裂解;当热解温度至444-464℃吋,主要是羧基和芳香核裂解;当热解温室达700℃以上吋,芳香核裂解趋于完全. 相似文献
6.
不同处理牛粪对植菜土壤腐殖质结构特征的影响 总被引：5，自引：0，他引：5
《水土保持学报》2015,(4)
通过元素组成分析法、红外光谱分析法(IR)、核磁共振光谱分析法(13 C-NMR)等现代分析方法,研究施用新鲜牛粪、腐解牛粪和蛴螬牛粪2a后对植菜轮作土壤胡敏酸(HA)和富里酸(FA)的影响。结果表明,与单施化肥(CK)相比,不同牛粪处理对植菜土壤胡敏酸和富里酸的元素组成影响有较大的差异,各牛粪处理均引发植菜土壤胡敏酸C含量和C/H降低,O含量、O/C和(N+O)/C升高,富里酸C含量和C/N升高,N、O含量和O/C降低,降低了植菜土壤胡敏酸的缩合程度,升高了土壤胡敏酸的氧化程度和极性,降低了植菜土壤富里酸的氧化程度。不同牛粪处理使植菜土壤胡敏酸的脂肪族化合物减少,且均含有苯基碳、酚羟基C、芳香醚和(或)与O、N等取代基邻、对位的连H芳香C,使芳构化程度增加,富里酸的脂肪族化合物增加,芳香类、羧基类化合物减少,芳构化程度降低。不同牛粪处理的植菜土壤未改变土壤腐殖质的基本结构特征,只引起植菜土壤的结构单元和官能团数量上的差异。 相似文献
7.
为探究不同生物质材料对蕉园土壤有机质及组成的影响,以木炭、椰壳炭、椰糠炭和与椰糠炭等碳量的椰糠为材料,分别以质量分数为2%和4%的用量加入土壤中,于室内常温培养并保持土壤含水量不变。在第15、30、60、90、120和180 d采集土壤,分析不同生物质材料对土壤有机质、胡敏酸、富里酸和土壤胡敏酸/富里酸的影响。结果表明:添加木炭、椰壳炭、椰糠炭和椰糠均能提高土壤有机质含量,并随添加量的增加而升高;添加木炭、椰壳炭、椰糠炭和椰糠均能加速土壤有机质的分解,添加椰壳炭对土壤有机质分解的影响相对较小。椰糠的添加主要是同时增加了土壤胡敏酸和富里酸碳含量,生物炭(木炭、椰壳炭和椰糠炭)的添加主要是影响了土壤胡敏酸与富里酸的相互转化。 相似文献
8.
为量化生物质炭对土壤腐殖质含量的影响程度,以不添加生物质炭土壤为对照,对不同土壤质地、土壤pH及生物质炭裂解温度、施用量、施用时长下生物质炭对土壤腐殖质含量的变化情况进行了Meta分析。结果表明：与对照相比,添加生物质炭显著提高了砂土腐殖质中的胡敏酸和胡敏素含量,平均提高幅度分别为18.6%和92.2%;增加了中性、碱性土壤中的胡敏酸含量,平均增幅分别为12.5%和13.7%;施用裂解温度为500~600℃的生物质炭对于土壤胡敏酸、富里酸和胡敏素含量的提升幅度最大,平均增幅分别为22.6%、14.1%和68.5%;生物质炭添加量为20~40 t/hm2条件下,显著提高了土壤胡敏酸、富里酸和胡敏素含量,平均增幅分别为23.7%、6.9%和84.6%;生物质炭施入土壤3个月内,胡敏酸含量显著升高,平均增幅为29.5%,在3个月到1年内增幅逐渐降低,1年后增幅又逐渐升高;生物质炭施入土壤6个月内,胡敏素含量增幅最高,平均为72.2%;随着生物质炭施用时间延长,土壤胡敏素含量的增幅逐渐降低。综上所述,施用裂解温度为500~600℃的生物质炭,在短期内对中性或碱性条件下的砂土及壤土中的腐殖质含量有较好的提升效果,随着施入时间的延长,该效果会逐渐稳定。 相似文献
9.
川南坡地不同退耕模式对土壤腐殖质及团聚体碳和氮的影响 总被引：5，自引：2，他引：3
通过对川南坡地进行退耕试验,研究坡地退耕成慈竹林、杂交竹林、桤木+慈竹林和弃耕地对土壤腐殖质及团聚体碳和氮的影响。结果表明,坡地退耕5年后土壤腐殖质(胡敏酸、富里酸和胡敏素)、活性腐殖质(活性胡敏酸和活性富里酸)及团聚体碳和氮含量、胡敏酸与富里酸比值和胡敏酸E4/E6值,以及可浸提腐殖质(胡敏酸和富里酸)、活性腐殖质及>0.25mm各粒径团聚体碳和氮分配比例均增加,并呈现出慈竹林>杂交竹林>桤木+慈竹林>弃耕地>农耕地的变化规律。土壤团聚体有机碳(氮)含量及其分配比例随土壤团聚体粒径的增加呈现出"V"形变化,其最小值分别出现在2～1mm和0.5～0.25mm粒径。说明川南坡地退耕对增加土壤腐殖质及团聚体碳和氮含量、改善土壤肥力状况和促进土壤碳固定具有重要的作用和意义。 相似文献
10.
稻草腐解过程中形成胡敏酸的组成和结构研究 总被引：2，自引：0，他引：2
通过稻草腐解实验,采用化学分析方法,研究了稻草腐解过程中土壤胡敏酸的化学特征的动态变化,旨在丰富农作物秸秆还田过程中的胡敏酸化学组成、性质与结构变化的特征。在试验培养条件下,施用稻草后土壤的有机碳含量提高了31.71%,腐殖质含量增加了51.93%,都在90d时达到最大值。施用稻草45d时的PQ值(HA在HS中所占的比例)明显降低,在90d和135d时的PQ值与45d时变化不大。施用稻草后土壤胡敏酸的色调系数(ΔlogK)逐渐减少,相对色度(RF)值迅速增大,胡敏酸的氧化程度和芳构化程度增强。胡敏酸的元素组成以碳为主,含量在52%左右,其次为氧。H/C的比值逐渐降低,O/C的比值不断增大。羧基和酚羟基为主要的酸性基团。羧基含量先降低,后随着腐解的进行,其含量不断升高;酚羟基的含量变化与羧基的含量变化趋势相反;羰基含量逐渐增加。施用稻草会引起紫色水稻土胡敏酸化学组成和结构的变化。 相似文献
11.
Experiments were conducted in growth chambers of the Phytotron to evaluate the effects of humic and fulvic acids on growth and ion uptake by tobacco plants grown to flowering. When small amounts of humic or fulvic acids were added to media used to grow seedlings, the dry weight of roots and tops and the height of the plants subsequently grown in a nutrient solution with small amounts of humic or fulvic acids increased, while at high rates of humic acids they decreased. Generally, there was a trend for low rates of humic acids to increase concentration of Ca and Mg in roots and leaves and to decrease Fe concentration in roots. The total content of N, K, P, Ca, Mg and Fe in the stalk and leaves increased in the presence of small amounts of humic or fulvic acids in the nutrient solution. Low rates of humic or fulvic acids in the growth medium facilitated the adsorption of Ca, Mg and Fe and their translocation within the plant. For high rates of humic acids there was a trend to decrease the total content of N, K, P, Ca and Fe in the roots and leaves of the plant. 相似文献
12.
间作小麦蚕豆不同生长期根际有机酸和酚酸变化 总被引：5，自引：0，他引：5
有机酸和酚酸是根系分泌物的主要组成部分,其在根际过程中发挥重要作用。根系有机酸和酚酸的分泌及其在根际中的含量与作物种类、营养状况、耕作方式有关。但人们对种植方式(间作)改变根际过程的研究并不多,尤其是间作条件下根际有机酸、酚酸的变化情况尚不清楚。小麦蚕豆间作是云南最常见的间作模式,它可以显著提高作物产量、提高养分利用效率,且其间作优势的形成与地下部根际效应密切相关。为了探讨间作对根际的影响,通过建立高效液相色谱(HPLC)分析方法,分析了盆栽试验条件下小麦蚕豆间作不同生育期根际有机酸和酚酸的变化特征。结果表明:在营养生长阶段(57~120 d),间作改变了蚕豆根际有机酸的含量,尤其在蚕豆分枝期(57 d)、结荚期(120 d),间作根际有机酸总量是单作的21.7倍和1.95倍,其中主要是促进了柠檬酸和富马酸在蚕豆根际的累积。在生殖生长阶段(120~169 d),间作提高了小麦根际有机酸的含量,尤其在孕穗期(120 d)、灌浆期(142 d),间作根际有机酸总量是单作的3.73倍和2.3倍;其中主要是改变了乳酸、富马酸和乙酸在小麦根际的累积。此外,间作降低了小麦根际酚酸的含量,抑制了酚酸在小麦根际的累积,但对酚酸种类没有影响;间作也改变了蚕豆根际酚酸的种类,其中主要是促进了蚕豆根际香草酸和丁香酸的累积、减少了香豆酸含量。总之,间作可能通过改变根际有机酸和酚酸的累积而改变根际过程。 相似文献
13.
Compositional changes of selected amino acids,organic acids,and soluble sugars in the xylem sap of N,P, or K‐deficient tomato plants 
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下载免费PDF全文 Jwakyung Sung Yejin Lee Seongsoo Kang Sangkeun Ha Hari B. Krishnan Taek‐Keun Oh 《植物养料与土壤学杂志》2015,178(5):792-797
Xylem sap plays a major role in long‐distance transport of water, nutrients, and metabolites. However, there is little information on the behavior of metabolites in mineral‐deficient xylem sap. For this reason, the time‐dependent changes in selected metabolites (amino acids, organic acids, and soluble sugars) from tomato xylem sap in response to nitrogen (N), phosphorus (P), or potassium (K)‐deficient condition were investigated. Tomato plants (Solanum lycopersicum L.) were grown hydroponically in liquid culture under three different mineral regimes: N‐deficient [0.5 mM Ca(NO3)2 and 0.5 mM KNO3], P‐deficient (0.05 mM KH2PO4), and K‐deficient (0.5 mM KNO3), respectively. Xylem sap was collected at 10:00 am after 1, 5, 15, and 30 d, and the selected metabolites were analyzed with liquid chromatography. All N, P, or K deficiencies led to a substantial increase in metabolites in the xylem sap. The predominant amino acid in the xylem sap was glutamine and, interestingly, all mineral deficiencies resulted in a substantial amount of γ‐aminobutyric acid (GABA). Additionally, organic acids (citrate and malate) and soluble sugars were strongly increased in all mineral deficiencies, and, in particular, the level of shikimate was greatly affected by N deficiency. Based on these data, it is necessary to clearly elucidate an unknown event taking place in xylem loading in a variety of environmental impacts, and we are now studying to expand our knowledge on metabolic and proteomic responses using GC‐MS and LC‐MS. 相似文献
14.
选择 2 8日龄断奶杜长大三元杂交仔猪 60头 ,随机分为 4组 ,每组 15头 ,分别饲喂以总氨基酸或可消化氨基酸为基础设计饲粮 ,研究其对仔猪生产性能和经济效益的影响。结果表明 :在可消化氨基酸相同条件下 ,适当降低饲粮粗蛋白质水平 ,并不影响仔猪生产性能 ( P>0 .0 5) ,且有利于控制腹泻和提高经济效益 ,但总氨基酸含量相同饲粮 ,其生产性能差异显著 ( P〈0 .0 5)。故生产上以可消化氨基酸设计日粮比总氨基酸设计日粮更合理 ,更接近仔猪对氨基酸需要。 相似文献
15.
The effects of aluminum on the accumulation of sugars, amino acids and organic acids in two hybrid cultivars of sorghum were studied.
The concentration of these organic compounds increased in the roots of the Al‐treated plants, mainly in the tolerant cultivar. The composition of the organic acid fraction showed a significantly higher accumulation of trans‐aconitate and malate in the tolerant cultivar as compared with the sensitive one. The higher levels of these acids in the Al‐treated plants could be interpreted as being indicative of a chelating detoxifying mechanism of aluminum in these plants. 相似文献
16.
Fred Denilson Barbosa da Silva Leonardo Angelo de Aquino Luís Eduardo Panozzo Tricia Costa Lima Paulo Geraldo Berger Denise Cunha Fernandes dos Santos Dias 《Communications in Soil Science and Plant Analysis》2016,47(7):809-817
Sunflower has been mentioned in the literature as a plant that requires large amounts of boron (B) to achieve a successful crop. This study aimed at evaluating the influence of sunflower fertilization with boron on the soil nutrient concentration, index leaf, seed yield, fatty acids’ composition of sunflower oil, and oil content. Cultivar M734 was selected for boron fertilization at 0, 3, 6, 9, and 12 kg ha?1 rates. The maximum economic return was obtained with 3.13 kg ha?1. Neither oil content nor fatty acid composition was affected by boron. With proper irrigation, the M734 cultivar was able to absorb boron in the 0 ? 40-cm layer, ultimately producing about 3000 kg ha?1 of seeds in soils with only 0.30 mg kg?1 of boron. Based on these results, it is suggested that the boron fertilization program be expanded to include the soil strata at 0?20 cm and 20?40 cm. 相似文献
17.
Adsorption efficiency of a continuous trapping system and its use for the collection of root exudates from cucumber 总被引：1，自引：0，他引：1 下载免费PDF全文
下载免费PDF全文 Root exudates comprising soluble low‐molecular‐weight organic compounds (LMWOCs) play a crucial role in the rhizosphere processes. Therefore, accurate determination of the composition and quantity of these compounds is of importance. A continuous trapping system (CTS) with XAD‐4 macroporous resin is widely used for collecting root exudates in hydroponics, and ion exchange resins are used in the separation of root exudates into neutral, acid and basic fractions. Here, we studied the adsorption equilibrium isotherms and dynamic adsorption properties of 27 standard LMWOCs on XAD‐4 resin. The adsorption isotherms of most LMWOCs matched the Langmuir isotherm equations. Furthermore, we investigated the adsorption efficiency of the CTS for LMWOCs and the recovery ratios during fractionation by ion exchange resins. The adsorption capacities of the CTS for LMWOCs which are non‐polar or having large non‐polar moieties were higher. The recovery ratios of most LMWOCs were larger than 80% during fractionation. The overall recovery ratios of LMWOCs were ca. 10, 20, and 30% for sugars, organic acids, and amino acids, respectively. Using this collection method, we present the composition and quantity of root exudates of cucumber (Cumumis sativus L.) at four different growth stages. The major components of root exudates were similar to previous works, whereas the quantities were different. The various collection methods may be the main reason for these differences. Therefore, it is necessary to study the overall recovery ratios when the compositions of root exudates via different collection methods are compared. 相似文献
18.
Methods for extraction and determination of ammonium, amides and soluble carboxylates in plant tissues are compared and discussed. The procedure recommended involves extraction of finely ground plant tissues with 0.2 M formic acid, determination of ammonium and amides in the extract by overnight alkaline hydrolysis and distillation in Conway microdiffusion dishes, measurement of extracted ammonium using Carlson's rapid diffusion‐conductivity instrument, and estimation of soluble organic acids by titration after separation and purification with ion exchange resins. The method described is reasonably rapid, and gives complete recovery and highly reproducible results. The final solution of organic acids is suitable for direct chromatographic analysis. 相似文献
19.
《Communications in Soil Science and Plant Analysis》2012,43(5):415-428
Abstract This study reports the relationship between N levels (22, 56 and 112 kg/ha) and its effect on yield and protein quality for five cultivars of soft winter wheat (Triticum aestivum L. em. Thell). The objective was to determine the relationship of amino acid content and total protein at various levels of N. The 56 and 112 kg N/ha rates resulted in higher wheat yields than the 22 kg N rate over the 3 yr. mean. A cultivar x N level interaction for yield occurred when certain cultivars did not respond to higher N rates in 1972. Total seed protein increased with each increase in If. Increasing N levels generally resulted in a higher amlno acid content of the seed. Cultivar effects were found for 6 of the 17 amino acids (threonine, serine, glutamic acid, proline, glycine and lysine) indicating that cultivars differed in total amino acid content. Cultivars Arthur and Holley gave the greatest response (percentage amino acid) to N application. Coker 68–8 was intermediate in response while Coker 68–15 and Blueboy showed small inconsistent responses to H application. 相似文献
20.
Summary Recent developments in biotechnology industries produce increasing amounts of byproducts with potential uses in agriculture. The present research focused on the nitrification of NH
inf4
sup+
-N in biotechnology byproducts added to soils, and on the effects of 29 naturally occurring organic acids (19 aliphatic and 10 aromatic) on nitrification in soils. A 10-g soil sample was incubated for 10 days at 30°C with 2.0 mg NH
inf4
sup+
-N in a byproduct or with 10 or 50 mol organic acid and 2.0 mg reagent-grade NH
inf4
sup+
-N. In condensed molasses-fermentation solubles, produced during the microbial fermentation of sugar derived from corn (Zea mays L.) and molasses derived from beets (Beta sp.), in the production of lysine as a supplement in animal food, the nitrification of NH
inf4
sup+
-N was similar to that of byproduct or reagent-grade (NH4)2SO4. Nitrite accumulated when either of these materials was added to a calcareous Canisteo soil. The NH
inf4
sup+
-N in slops (produced during microbial fermentation processes occurring in the production of citric acid) was not nitrified in soils. Some organic acids inhibited, whereas others activated, nitrification in soils. Formic, acetic, and fumaric acids enhanced the production of NO
inf2
sup-
-N in a calcareous Canisteo soil, whereas all other aliphatic and aromatic acids studied decreased the accumulation of NO
inf2
sup-
-N. It is concluded that the addition or production of organic acids in soils affects the microbial dynamics, leading to significant changes in rates of nitrification and possibly in other N-transformation processes in soils. 相似文献