生物质炭醋糟复配物代替草炭对辣椒幼苗生长的影响

生物质炭的农业利用日益受到关注。针对草炭资源日益耗竭的问题,以药渣炭、木屑炭和猪粪炭为试验对象,配比一定量的醋糟,分析了不同配比生物质炭复合基质对辣椒幼苗生长的影响,探讨了生物质炭复合基质代替草炭基质的可能性。试验结果表明:生物质炭在与醋糟按4∶2、3∶3、2∶4等不同配比混合后,基质的pH大多数在6.0~7.5,基质的通气孔隙有所提高。综合整个幼苗生育期,含20%生物质炭的各复合基质处理的辣椒幼苗株高、茎粗、叶面积、地上部生物量均显著优于对照草炭基质;含20%、40%药渣炭的基质处理的幼苗根表面积、根体积表现较好,在前期与草炭基质无显著差异,后期显著高于草炭基质。药渣炭和木屑炭与醋糟混配基质的壮苗指数优于草炭处理,其中B1A2(药渣炭∶醋糟∶蛭石∶珍珠岩=4∶2∶3∶1)、B1A4(药渣炭∶醋糟∶蛭石∶珍珠岩=2∶4∶3∶1)、B2A4(木屑炭∶醋糟∶蛭石∶珍珠岩=2∶4∶3∶1)处理的壮苗指数均显著高于其他处理。综合评价各生长指标,B1A2和B1A4处理基质的表现最好,可代替草炭基质在辣椒育苗上应用。     

基于废弃物的潞安煤矿废弃地改良土壤基质配比研究

为解决潞安矿区煤矸石山、塌陷地生态修复缺土少肥问题,本研究将粉煤灰、污泥与垃圾堆肥以5%、10%、20%体积比例正交混合配制改良土壤基质进行盆栽试验,观测不同配比土壤的理化性质、养分及重金属含量、高羊茅与紫叶小檗生长状况,并用主成分–聚类分析法筛选最优配比。结果表明:添加垃圾堆肥可以提高土壤有效养分与有机质含量,对土壤理化性质改良有明显效果;添加污泥仅提升土壤有效磷含量;添加粉煤灰在降低土壤容重、增大总孔隙度与非毛管孔隙度上效果明显,但对土壤p H、阳离子交换量(CEC)与碱解氮的改良具有显著负效应。各废弃物改良基质的碱解氮、有效磷、速效钾、有机质等含量均较高,土壤重金属含量也处在安全范围,而土壤容重、非毛管孔隙、pH、电导率(EC)与CEC等指标性质较优的处理组为粉煤灰∶污泥∶垃圾堆肥∶土=5%∶20%∶20%∶55%、10%∶10%∶20%∶60%、20%∶5%∶20%∶55%3个处理。经过综合筛选,本研究基质最优混合配比为粉煤灰∶污泥∶垃圾堆肥∶土=5%∶20%∶20%∶55%,可作为当地矿区废弃地生态修复客土材料推荐方案。     

木霉制剂改良滨海盐渍土台田生态效应

生物改良滨海盐渍土是一种投资少、需时短、见效快、长期受益的环保生态型技术。通过田间试验将木霉制剂[活性成分为木霉分生孢子,1×107(CFU)·g~(-1)]施用到滨海中度盐渍土台田(含盐量2.99 g·kg~(-1),砂壤土),对土壤改良台田试验区不同处理(施用木霉制剂和常规对照处理)及辅助试验区日光温室(含盐量0.98 g·kg~(-1),壤土)、滨海轻度盐渍土开垦田(含盐量1.75 g·kg-1,轻壤土)、滨海重度盐渍土河滩地(含盐量26.19 g·kg~(-1),砂壤土)的耕层土壤取样室内测定,探究木霉在滨海中度盐渍土台田施用的生态效应。滨海中度盐渍土台田木霉处理与对照处理相比,土壤紧实度提高177.04%,土壤水稳性团聚体数量(≥0.25 mm)提高265.78%,土壤含水率提高320.83%,土壤碱解氮、有效磷、速效钾和有机质含量分别提高96.14%、42.17%、105.65%和63.79%;土壤稀释法培养微生物,细菌、放线菌、真菌、固氮菌数量比对照分别提高170.95%、82.68%、152.17%和471.93%。滨海中度盐渍土台田木霉处理与滨海重度盐渍土河滩地比较,有利于植物生长的指标土壤紧实度、水稳性团聚体、有机质和微生物群落数量分别提高1.53倍、2.11倍、3.20倍和28.33倍,不利植物生长的水溶性盐下降96.60%;滨海中度盐渍土台田通过木霉制剂改良,土壤紧实度、总孔隙度、含水率、有效磷、有机质和微生物数量与滨海轻度盐渍土开垦田相比无显著差异;滨海中度盐渍土台田木霉处理后土壤容重降低、总孔隙度增加,与高产日光温室非盐渍化土壤相比接近。滨海重度盐渍土通过沙土抬高1.2 m筑田变为中度盐渍土,降盐效果较好,再通过加入生物改良措施提高土壤营养和有益微生物,优化土壤团粒结构,利于提高滨海中度盐渍土台田改良效率和质量,促进滨海中度盐渍土台田生态的改善。     

生物质炭与盐酸配施对苏打盐渍土理化性状的影响研究

为了评价生物质炭与盐酸配施对苏打盐渍土的改良效果,本研究将不同配比的生物质炭和盐酸混合,添加于苏打盐渍土中,通过室内培养实验,研究了不同生物质炭和盐酸混合处理对轻度、中度苏打盐渍化土壤的p H、电导率、容重、渗透系数影响,以及所生长作物燕麦株高和干重等的影响。结果表明,2%生物质炭配合30 m L·kg-1的0.5N盐酸处理,使轻度苏打盐渍化土壤的p H降低到7.61,容重下降19.2%,渗透系数升高31.6%,燕麦株高增加6.3%,干重增加65.5%,改良效果与施用脱硫石膏的对照组无显著差异,可以作为轻度苏打盐渍化土壤的改良剂配方;5%生物质炭和10 m L·kg-1的0.5N盐酸组合处理,使中度苏打盐渍化土壤p H降低到8.06,容重下降19%,渗透系数从2×10-4cm·s-1升高到1.7×10-4cm·s-1,燕麦长势良好,可以有效改良中度苏打盐渍化土壤。表1,图12,参20。     

不同施用方式下污泥堆肥对土壤性质和草坪生长的影响

为解决城市污泥处理难题,探讨污泥堆肥及其不同施入方式对绿地土壤的改良效果,进行了污泥堆肥绿地土壤改良试验。试验设混合(H)、覆盖(F)、混合+覆盖(HF)3种施入方式,结果表明:不同施入方式均能显著降低绿地土壤容重,提高土壤中有机质、碱解氮、速效钾、有效磷含量,HF和H的改良效果最好;不同施入方式还均能显著促进草坪生长和分蘖,其中HF,F,H处理的分蘖密度分别比对照高45%,37%,32%;F处理的杂草抑制率在96%以上,HF为78%,H处理未能抑制杂草;各施入方式均能显著提高土壤微生物碳和土壤微生物氮含量,改良1年后,F、H和HF的土壤微生物碳含量分别是对照2.4,3.1,3.4倍,微生物氮含量分别是对照的1.7,3.0,2.8倍;与对照相比,HF处理与H处理的土壤脲酶、酸性磷酸酶和蔗糖酶活性均显著提高。     

粉煤灰与有机肥配施对风沙土理化性质及黑麦草生长的影响

为研究粉煤灰与有机肥配施对风沙土理化性质及黑麦草生长的影响,在施有机肥30 t·hm²的条件下,设4种粉煤灰施用水平:0(单施有机肥)、60、120、240 t·hm-2,以风沙土为对照(CK),进行盆栽试验。结果表明:(1)粉煤灰与有机肥配施后,土壤容重降低,总孔隙度增加,自然含水量、田间持水量、饱和含水量较对照分别提高54.75%～76.67%、28.69%～85.24%、8.57%～26.08%;(2)单施有机肥或与粉煤灰配施后,土壤pH值提高,电导率增大,有机质、碱解氮、有效磷、速效钾含量较对照分别增加147.02%～367.55%、165.57%～300.88%、133.92%～165.84%、132.71%～175.68%,单施有机肥处理肥力最高,配施粉煤灰后,有机质及各速效养分含量降低;(3)配施粉煤灰提高了土壤中镉、铬、铅、砷元素的总量,但未造成土壤污染,评价结果显示土壤重金属污染等级为安全,且潜在生态风险低;(4)单施有机肥可促进黑麦草生长,配施粉煤灰后黑麦草长势更佳,与单施有机肥相比,株高、地上部鲜重、分蘖数分别增加12.30%～32.81%、3.49%～39.96%、10.42%～18.75%;(5)通过主成分分析综合评价各处理,配施粉煤灰120 t·hm²+有机肥30 t·hm²后土壤理化性质最佳,黑麦草长势优良,为各处理中最优。     

醋糟菌糠对3种作物土壤微生物及酶活性的影响

为研究醋糟菌糠作为一种生物肥料对土壤肥力的影响,为解决食用菌菌糠对环境污染及其有效利用提供科学依据,本文通过田间试验,对玉米、高粱、糯玉米3种作物基施醋糟菌糠后不同生育期的土壤脲酶、蔗糖酶和过氧化氢酶活性,细菌、放线菌和真菌数量,及微生物量碳、氮含量进行测试。研究结果表明:1)醋糟菌糠显著提高了作物根际土壤细菌、放线菌和真菌的数量。在作物整个生育期,加入醋糟菌糠的土壤细菌数量比对照提高32%~54%;放线菌数量在成熟期提高明显,玉米田土壤放线菌数量增幅最大,为101%;真菌数量变化总体趋势呈现先升高后下降的趋势。2)醋糟菌糠的施入增加了作物根际土壤脲酶、过氧化氢酶、蔗糖酶的活性。种植高粱、玉米和糯玉米土壤的脲酶活性增长率分别为239%、189%和185%;3种作物的土壤过氧化氢酶活性在抽穗期最高,最大增长率为40%;3种作物的土壤蔗糖酶活性在不同生育期变化趋势不同,玉米各生育期土壤蔗糖酶活性变化较为稳定,其增长率分别为38%、28%、48%。3)醋糟菌糠的施入增加了作物根际土壤微生物碳氮的含量,不同生育期3种作物的土壤微生物碳含量增幅为58.10~407.67 mg·kg-1,微生物氮含量增幅为11.98~27.55 mg·kg-1。由此可见,醋糟菌糠的施用可以增强土壤生产力的可持续性,从而达到保护和改善土壤环境的效果。同时该研究也为醋糟菌糠的有效利用提供了一定的科学依据。     

生物质炭对黄棕壤理化性质及龙脑樟幼苗生长的影响

以南京林业大学下蜀林场黄棕壤为试验对象,采用室外盆栽试验,研究生物质炭不同施用量(炭土质量比0、1%、2%、4%)对黄棕壤理化性质及龙脑樟幼苗生长的影响。结果表明:生物质炭可有效改良黄棕壤物理性质,4%施用量改良效果最好,与仅施化肥处理相比,土壤总孔隙度、饱和持水量、毛管持水量和田间持水量显著提高,土壤容重显著降低(P0.05);施用生物质炭可显著提高土壤pH(P0.05),改善土壤酸碱性;生物质炭施用对土壤氮磷有效性影响显著(P0.05),低施用量下土壤碱解氮含量最高,高施用量下土壤有效磷含量最高。生物质炭1%施用量下,龙脑樟叶片产量最高(41.54 g),分别比对照和仅施化肥处理提高141.53%和11.16%;而苗高相对生长速率较仅施化肥处理显著降低6.79%,有利于矮化苗木。可见生物质炭改良土壤理化性质和促进苗木生长的最佳施用量并不相同。考虑到经济效益,1%的生物质炭施用量对龙脑樟叶片产量的提高较为适宜。     

不同配比的木醋肥对香樟林土壤性状的影响

将不同配比的木醋肥施用于香樟林地中,通过测定施肥后林地土壤微生物数量、酶活性、土壤部分化学性质以及植物黄化相关指标的变化情况,旨在选择效果明显的配比应用于城市绿地绿化植物的养护中.试验结果表明,6种试验配方均能不同程度地改善香樟林土壤性状,主要表现在:微生物数量增加、酶活性提高、化学性质得到改良,同时香樟黄化也得到有效控制.低浓度木醋液中加入低量有机肥,对土壤微生物有一定的抑制作用,并且化学性质和黄化改良效果不如其他处理明显;从生产应用、使用价值等综合效果来看,中低浓度木醋液中加入木炭粉(木醋液∶木炭粉比例为1∶5(V∶M))和中高量有机肥的处理改良效果最好.     

稻壳深施对碱土物理性质和苜蓿产量的影响

为探索改良盐碱土新的技术和方法,调查比较了深耕、稻壳深施改良苏打碱土土壤物理性质和增产苜蓿的效果,结果表明:(1)稻壳深施降低土壤容重、提高土壤孔隙度和通透性能、改善三相比的效果明显,而仅仅通过深耕改良苏打碱土壤物理性质效果的持久性差。(2)改土后连续2年,深耕区增产效果不明显,第1年和第2年分别比对照减产0.1%和4.2%,2年平均增产1.7%;稻壳深施区增产效果显著,第1年和第2年分别比对照增产25.4%和33.2%,2年平均增产28.8%。可见,稻壳深施改良碱土,增产效果好,且具有明显的埋存效应,为本区域内的有机资源利用开辟新的途径和方法,应用前景广阔。     

木醋液土壤灌溉对土壤养分、番茄产量及品质的影响

采用田间小区试验,研究了木醋液不同灌溉量对土壤养分、盐碱和番茄产量及品质的影响。结果表明,土壤灌溉木醋液可提高土壤碱解氮、速效钾、有效磷含量,且使用量越大,效果越明显,其中有效磷含量增加最为显著,与对照相比可提高9.27%~25.51%;木醋液也可提高土壤有机质及全盐含量,但与对照相比差异不显著;木醋液还可降低土壤p H值,与对照相比可降低0.14~0.27个单位。木醋液低[2.25 t/(次·hm~2)]、中[4.50 t/(次·hm~2)]用量能显著提高番茄株高、增加产量,其中低用量效果最好,与对照相比可提高株高10.53%,增加产量11.52%;高用量[7.50 t/(次·hm~2)]对番茄生长具有一定抑制作用。木醋液可提高番茄可溶性糖含量5.27%~10.28%,提高Vc含量3.46%~17.15%,降低硝酸盐含量4.25%~15.33%,对有机酸含量影响不明显。综上所述,建议设施土壤番茄季木醋液灌溉量为2.25~4.50 t/(次·hm~2)为宜。     

冬季咸水结冰灌溉下滨海重盐碱地土壤水盐动态及对棉花出苗和产量的影响

在河北省滨海区,连续3年对当地的盐碱地进行了冬季咸水结冰灌溉,并对土壤的耕层水盐动态、棉花出苗和产量以及植株的盐离子状况进行了观测。结果表明:利用矿化度为8.15~14.27 g.L 1、灌水量为180mm的地下咸水,对滨海盐碱地进行冬季结冰灌溉,后期结合地膜覆盖可显著降低土壤盐分含量和提高土壤含水量。咸水结冰灌溉处理2009—2011年棉花播种期土壤盐分含量分别为0.32%、0.29%和0.17%,土壤含水量分别为26.2%、25.0%和24.2%,保证了棉花正常出苗,3年的棉花出苗率均达到85%以上。结冰灌溉年限越长越有利于土壤盐分的淋洗。苗期棉花根、茎和叶片Na+含量比对照降低57.6%~64.5%,而相应的K+和Ca2+含量显著高于对照(不灌溉不覆膜处理)棉苗,避免了对苗期棉花的单盐伤害。随着当地雨季的来临,棉田耕层土壤可实现周年脱盐,保证了棉花的正常生长,籽棉产量达到2 643.8~3 607.7 kg.hm 2,并且3年的产量呈逐年上升趋势,实现了滨海重盐碱区水土资源的高效利用和棉花丰产。     

连作对高粱生长及根区土壤环境的影响

以玉米－高粱轮作为对照,研究连作对高粱生长、产量的影响及根区土壤中酶活性和微生物的变化。结果表明：高粱连作3年对产量的抑制开始显现。与轮作相比,连作3年高粱的株高、茎粗、叶面积、生物量显著降低,连作4年更为明显;连作4年高粱根系生长也明显受到影响,0~40 cm深度范围内根系的生物量、根表面积和根体积分别仅为轮作的61.5％、84.4％、73.8％。连作4年增加了土壤中可培养真菌数量,在拔节期和灌浆期分别是轮作的1.9、1.3倍,而对细菌和放线菌的影响没有明显规律;连作显著增加土壤中过氧化氢酶、蔗糖酶的活性,分别比轮作增加了14.7％、17.2％。由此可见,连作不仅抑制高粱植株的生长,并对土壤中微生物区系组成和酶活性产生显著影响。     

The Accumulation of Boron in Agropyron elongatum Grown in Coal Fly Ash and Sewage Sludge Mixture

A greenhouse pot experiment was conducted to investigate the boron (B) release capacity of coal fly ash and sewage sludge mixtures, and the accumulation of B in Agropyron elongatum after two consecutive growing seasons. Sludge was amended with fly ash at application rates of 0, 5, 10, 35, and 50% (w/w), and each mixture was then mixed with a loamy soil at either 1:1 or 1:5 (v/v). Both water soluble B (WS-B) and hot water soluble B (HWS-B) increased with increasing fly ash amendment rate. Shoot B concentrations also increased significantly according to the rate of ash amendment. The ash-sludge mixture improved plant growth with the highest total dry weight yield at 10% ash amendment rate. Boron toxicity symptoms in leaf tips were observed at 35% and 50% ash amendment rate at both soil mixing ratios. Hot water soluble B and WS-B decreased significantly after consecutive cropping of Agropyron especially at low ratio of mixure with soil i.e., 1:5 (v/v). However, soil available B contents at ≥ 35% ash application rate and 1:1 (v/v) soil mixing ratio were still excessive for normal plant growth, suggesting that deleterious effects on plant growth would be experienced in later seasons owing to the high amounts of residual B.     

Formulation of Environmentally Sound Waste Mixtures for Land Application

Major impediments to the land application of coal combustion byproducts (fly ash) for crop fertilization have been the presence of heavy metals and their relatively low and imbalanced essential nutrient concentration. Although nutrient deficiencies, in particular N, P, and K, may be readily augmented by adding organic wastes such as sewage sludge and animal manure, the indiscriminate application of mixtures to crops can cause excessive soil alkalinity, imbalanced nutrition (P, Mg), phytotoxicities (B, Mn, ammonia, nitrite), and unspecified contamination of the food chain by elements such as As. In this study, nutrient availability data and linear programming (LP) were used to solve these problems by formulating fly ash-biosolid triple mixtures which complied with both plant and soil fertilization requirements, and met existing U.S.A. environmental regulations for total As application in sewage sludge (EPA-503). Thirteen different fly ash samples were LP-formulated with sewage sludge, poultry manure, CaCO₃, and KCl to yield 13 unique mixtures, which were then evaluated in greenhouse pot experiments. Results indicated that normal growth and balanced nutrition of sorghum (Sorghumbicolor L.) and soybean (Glycine max (L.) Merr.) crops were achieved in all mixtures, comparable to a balanced fertilizer reference treatment, and significantly better than the untreated control. Phytotoxic levels of B, NH₃, NO₂ ^-, overliming problems, and excessive As levels which were previously encountered from indiscriminate use of these waste materials, were all well controlled by LP-formulated mixtures. Most fly ash quantities in mixtures were limited by either available B (< 4 kg ha^-1) or total As (< 2 kg ha^-1) restrictions during formulation, while the most alkaline fly ash was limited by its high calcium carbonate equivalence (CCE = 53.9%). These results confirmed that fly ash land application should not be at arbitrary fixed rates, but should be variable, depending on the soil, crop, and particularly the fly ash chemistry.     

Uptake of multielements by corn from fly ash-compost amended soil

Fly ash was collected from a coal-fired power plant in and near the U.S. Department of Energy Savannah River Site to study the feasibility of the application of fly ash compost mixture to soils for the availability and uptake of various elements by corn (Zea mays L.). The crop was grown in potted Ogeechee sandy loam soil using eight treatments: soil alone, soil amended with 15% compost, and soil amended with 2, 5, 10, 15, 20 and 25% of fly ash-amended compost. It was observed that 20–25% fly ash and compost soil ratio treatments generally increased plant growth and the yield. The plant uptake of K, Mn, and Cu increased with increasing percentages (2–25%) of fly ash+compost: soil ratios. The total content of K in plants was positively correlated with the dry matter yield of corn. This study indicates that the application of fly ash blended with compost to soil is beneficial to corn production without causing any deleterious effects on plant growth and plant composition.     

3种固沙材料与风沙土复配后土壤改良效应及其质量评价

揭示风沙土复配其他固沙材料后的土壤质量变化及改良效应对研发防沙固沙新材料具有重要的指导意义。以乌兰布和沙漠风沙土为对照(CK),采用粉煤灰、脱硫石膏、牛粪3种固沙材料按干质量比15%,25%与风沙土进行复配,研究了不同材料与配比复配土壤对机械组成、养分含量、金属含量的改良效应,运用最小数据集构建、隶属度计算与土壤质量指数计算等方法评价了复配土壤质量。结果表明：(1)不同复配土壤的机械组成均发生了改变,粉粒、粗砂等难蚀、较难蚀颗粒体积分数增加,易蚀的细砂体积分数降低。(2)除石膏复配土壤各养分指标与CK相近外,其余复配土壤有机碳含量较对照提高1.2～10.4倍,牛粪复配土壤在提高养分含量方面显著高于其他材料;以牛粪和石膏为材料的复配土则分别增加或降低了沙土中的金属含量,而粉煤灰复配土的Cr, As较CK下降。(3)不同复配土对土壤理化性质作用影响各异,粉煤灰在粒径改良方面较优,牛粪在养分提升方面效果显著,石膏在重金属含量降低方面作用明显,粉煤灰石膏混合复配则综合了二者的优势。(4) 3种固沙材料均在不同程度上提高了复配土壤的质量,但复配土壤质量仍处于较低水平。综上,不同复配比例组合中,1...     

Characteristics of synthetic soil aggregates produced by mixing acidic “Kunigami Mahji” soil with coal fly ash and their utilization as a medium for crop growth

Abstract

This study was carried out to examine the characteristics and potential utilization of synthetic soil aggregates (SSA) produced by mixing acidic “Kunigami Mahji” soil in Okinawa, Japan, with waste materials, such as coal fly ash, used paper and starch, as media for crop growth. A series of different SSA were produced by incorporating various percentages (i.e. 0, 20, 40, 60, 80 and 100%) of coal fly ash into the “Kunigami Mahji” soil with used paper and starch. The particle density and bulk density of the original “Kunigami Mahji” soil were 2.67 and 1.23 g cm^?3, respectively. The increased percentages of added coal fly ash, used paper and starch significantly decreased the particle and bulk densities of SSA compared with the original “Kunigami Mahji” soil because of the low particle and bulk densities of the coal fly ash (2.10 and 0.96 g cm^?3, respectively). The SSA particle density varied between 2.39 and 2.14 g cm^?3, and bulk density varied between 0.72 and 0.81 g cm^?3, depending on the additional percentages of coal ash from 20–100%. Maximum water-holding capacity and saturated hydraulic conductivity were increased with the formation of SSA with coal fly ash, used paper and starch binder compared with the original “Kunigami Mahji” soil. The saturated hydraulic conductivity values of the SSA increased because of their low bulk density compared with the original soil. The addition of coal fly ash, used paper and starch to the acidic (pH = 4.62) “Kunigami Mahji” soil to form SSA increased the pH (6.70–9.96), electrical conductivity, exchangeable cation concentration and cation exchange capacity. The addition of coal fly ash up to 60% increased the aggregate strength. The growth and yield of komatsuna and soybean crops with SSA as a crop growth medium was assessed. Both crops showed the highest growth and yield when grown with SSA containing 20% of coal fly ash. Synthetic soil aggregates containing more than 20% of coal fly ash reduced plant growth and yield. Therefore, SSA produced from “Kunigami Mahji” soil with 20% of coal fly ash, used paper and starch can be successfully used as a medium for crop growth.     

多功能调理剂对甘肃河西内陆盐渍土理化性质和甜高粱产草量的影响

在甘肃河西内陆的盐渍土上,采用田间试验方法,研究了多功能调理剂对盐渍土理化性质和甜高粱产草量的影响。结果表明:多功能调理剂最佳配方组合为:A2B2C1(即营养因子1.80 t/hm~2、有机生态肥72 t/hm~2、盐渍土改良材料1.20 t/hm~2)。不同种类盐渍土改良剂对盐渍土体积质量、pH、EC和全盐由大到小的变化顺序依次为:盐渍土荒滩(CK)抗盐丰盐碱土改良剂禾康盐碱土改良剂盐碱土改良剂多功能调理剂;总孔隙度、团聚体、饱和持水量、有机质、速效氮磷钾、甜高粱产草量由大到小的变化顺序依次为:多功能调理剂盐碱土改良剂禾康盐碱土改良剂抗盐丰盐碱土改良剂盐渍土荒滩(CK)。多功能调理剂与盐渍土荒滩(CK)比较,盐渍土体积质量、pH和全盐分别降低28.05%、3.63%和62.16%;总孔隙度、团聚体和饱和持水量分别增加45.55%、45.55%和32.91%;有机质、碱解氮、速效磷和速效钾分别增加11.74%、145.01%、206.56%和13.35%;甜高粱产草量出苗率、株高、茎粗、单株鲜重和产草量分别增加123.69%、120.00%、105.29%、133.33%和181.13%。多功能调理剂施用量与盐渍土孔隙度、团聚体、持水量、有机质、速效氮磷钾、微生物数量、甜高粱产草量之间呈正相关关系,与体积质量、pH和全盐之间呈负相关关系。多功能调理剂施用量与甜高粱产草量间的回归方程为:y=32.64+0.5561x–0.0003x2,最佳施用量为75.00 t/hm~2,甜高粱产草量为72.66 t/hm~2。在盐渍土上施用多功能调理剂,有效地改良了盐渍土理化和生物学性质,降低了体积质量、pH、EC和全盐,增加了总孔隙度、团聚体、饱和持水量,提高了有机质及速效氮磷钾和甜高粱产草量。     

水分胁迫和粉煤灰添加对风沙土颗粒分形维数及肥力的影响

探讨不同比例粉煤灰在水分胁迫下与风沙土复配对沙土颗粒分形维数及肥力的影响，为毛乌素沙地土壤肥力提升提供理论依据。采用盆栽控水方法，设置4个粉煤灰水平(F0、F1、F2、F3,分别占风沙土干重的0,1%,5%,10%)和3个水分梯度[W1、W2、W3,分别占田间持水量的(75±5)%,(55±5)%,(35±5)%],采用分形维数反映在水分和粉煤灰作用下风沙土粒径分布特点，利用主成分分析结合聚类分析方法评价不同处理下风沙土肥力变化。结果表明：(1)在相同水分条件下，风沙土分形维数随着粉煤灰复配比例的增加而增加。(2)在相同粉煤灰复配比例下，风沙土中硝态氮(NO₃^-—N)含量随着水分胁迫利用效率提高，呈现出增加的趋势。(3)粉煤灰和水分处理条件下风沙土中全氮(TN)含量均处于较低水平，在实际生产过程中应考虑配施氮肥。(4)对风沙土肥力综合评价结果表明，粉煤灰10%复配比例效果较好，且在干旱情况下有一定的适用性。