共查询到20条相似文献，搜索用时 171 毫秒
1.
低磷环境下接种丛枝菌根真菌促进紫花苜蓿生长和磷素吸收的机理 总被引：1，自引：0，他引：1
2.
【目的】研究接种AMF (arbuscular mycorrhiza fungi)提高干旱胁迫下土壤微生物生物量和酶活性，及提高土壤养分有效性的效果，为旱作区作物生产提供菌根调控技术。【方法】盆栽试验连续进行了两年，供试燕麦品种为‘坝莜18号’，栽培基质为生土与河沙以3∶1混合，每盆添加N 0.315 g、P2O5 0.087 g。试验设两个土壤相对含水量(田间持水量的75%和55%)，并分别设接种AMF和不接种AMF处理，共4个处理。在燕麦抽穗期取样测定土壤微生物特性指标和养分含量，及燕麦各器官氮、磷积累量；成熟期测定燕麦籽粒产量。【结果】接种AMF条件下，55%土壤相对含水量处理的燕麦根系AMF侵染率比75%土壤相对含水量处理显著降低23.28%～33.35%。与正常水分条件相比，干旱胁迫显著降低了土壤微生物生物量碳和酶活性，降低了土壤有效氮、磷含量，pH和有机碳含量升高。干旱胁迫下，与未接种AMF相比，接种AMF显著提升了土壤微生物生物量碳、氮和磷含量，提高了土壤蔗糖酶、脲酶和碱性磷酸酶活性，速效磷含量显著增加了4.92%～5.41%，... 相似文献
3.
有机物料添加对内蒙古河套灌区碱化土壤可溶性有机碳的影响 总被引：1，自引：1，他引：0
通过研究不同有机物料添加对内蒙古河套灌区碱化土壤可溶性有机碳含量变化的影响，寻找合理高效的增碳方式，降低碱化土壤有机碳损失。以内蒙古河套灌区轻度、中度盐碱土为对象进行田间试验，设置生物炭（BC）添加、羊粪（GM）添加，对照（CK）3个处理，对比和分析不同有机物料添加后土壤有机碳（SOC）、可溶性有机碳（DOC）、土壤理化性质的变化。结果表明：（1）与CK相比，轻度碱化土壤BC、GM处理土壤DOC含量分别增加3.28%，20.66%，SOC含量增加5.40%，10.30%，中度碱化土壤BC和GM处理下可溶性碳增加41.32%，74.10%，土壤SOC含量增加60.24%，79.16%；（2）轻度碱化土壤BC和GM处理土壤DOC含量与SOC含量呈负相关，中度碱化土壤BC和GM处理下呈正相关；（3）盐碱土壤SOC、DOC含量主要与土壤pH、电导率的变化有关；BC处理较GM处理相比土壤电导率低约1.93%~29.15%，而GM处理土壤pH、碱化度比BC处理低0.31%~1.53%，7.10%~24.63%。总体来看，有机物料添加后均能使土壤中SOC、DOC含量提高，不同程度地降低土壤碱化程度，且羊粪添加较生物炭略好，因此羊粪添加对河套灌区碱化土壤碳含量的提高比生物炭添加更有效，土壤改良效果更好，土壤理化性质改善更明显。 相似文献
4.
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
5.
绿肥翻压接种丛枝菌根真菌和深色有隔内生真菌对玉米生长及氮素利用的影响 总被引：1，自引：0，他引：1
6.
《农业环境与发展》2021,(1)
为探讨耐盐植物种植对滨海盐土化学性质及微生物群落结构的影响,在滨海盐土环境下,以种植耐盐植物费菜(Sedum aizoon L.)、田菁(Sesbania cannabina(Retz.)Poir.)、蒲公英(Taraxacum mongolicum Hand.-Mazz.)的样地和未种植植物的裸地土壤(CK)为研究对象,采用土壤农化分析技术和磷脂脂肪酸(PLFA)生物标记法,对土壤化学性质、微生物群落结构及多样性进行分析。结果表明,与裸地比较,种植植物样地土壤电导率和速效钾含量均显著下降,分别下降了20.26%~57.21%和23.42%~37.80%;而有机质含量和有效磷含量显著升高,分别升高了39.16%~53.01%和106.48%~259.92%。种植植物样地土壤中PLFA种类明显增加,微生物群落也有所改变,3个植物样地土壤中总PFLAs含量和革兰氏阴性菌、放线菌、AM真菌、真核生物、真菌PFLA含量显著升高,分别升高21.53%~103.32%、4.96%~63.37%、82.91%~222.72%、50.00%~160.25%、32.05%~268.59%、19.39%~454.77%;真菌/细菌(F/B)PFLA含量也显著升高1.00~6.50倍,而革兰氏阳性菌PFLA含量和革兰氏阳性菌/革兰氏阴性菌(G+/G-)PFLA含量却显著下降,分别下降了48.06%~57.78%和59.77%~68.68%。此外,种植植物样地土壤微生物群落结构多样性也明显提高。研究表明,种植费菜和蒲公英可以降低滨海盐土土壤电导率,有利于土壤有机质的积累,同时其促进多种微生物的繁殖,可有效改善滨海盐土的微生态环境。 相似文献
7.
减氮条件下生物炭对甜菜盐碱胁迫的缓解效应 总被引：1，自引：0，他引：1
8.
通过田间试验,一次性施入花生壳来源生物炭,研究其对土壤改良、蔬菜生长、蔬菜品质影响及其作用的持续效应,为土壤改良的应用提供科学依据。生物炭用量设置0、2.5、5、10 t·hm~(-2)4个水平,2014~2016年共进行16个月多茬上海青、油麦菜和生菜3种蔬菜轮作的田间试验,在各茬蔬菜收获时测定产量,并采集蔬菜样品测定可溶性糖、硝酸盐及Vc含量,同时采集各小区土壤样品测定pH值、碱解氮、有效磷、速效钾及有机碳含量。研究结果表明,不同用量花生壳生物炭可提高土壤pH值0.1~0.8单位,提高土壤有机碳1.4%~31.4%,使蔬菜增产6.2%~96.5%;但对蔬菜可溶性糖、硝酸盐及Vc含量没有明显影响。花生壳生物炭对前两茬蔬菜收获时的土壤速效钾含量具有显著提高作用,对以后各茬蔬菜收获时的土壤速效钾、所有茬次蔬菜收获时的土壤碱解氮及有效磷含量均没有明显影响。与对照处理相比,5 t·hm~(-2)花生壳生物炭施用效果最好,可提高土壤pH值0.3~0.8单位,提升土壤有机碳4.6%~19.0%,增产蔬菜7.9%~96.5%。连续种植多茬蔬菜后,5 t·hm~(-2)花生壳生物炭处理的土壤pH值仍然比对照处理提高16.9%、土壤有机碳提升8.5%,蔬菜产量增加18.7%。因此,一次性施用适量花生壳生物炭在16个月内对连续多茬蔬菜试验具有持续增产和改土作用。 相似文献
9.
磷石膏、红糖等对蚯蚓改良滨海盐土的促进作用 总被引：3，自引：0，他引：3
前期研究表明,施入园林废弃物作为饵料并投放蚯蚓能够降低滨海盐土盐分。通过田间对比试验,研究同时添加磷石膏和红糖对蚯蚓改良滨海盐土的促进作用。结果表明,在每平方米施入6.5 kg园林废弃物及50条蚯蚓(平均质量0.334 g)的基础上,添加磷石膏能够显著降低土壤pH以及水溶性钠离子(Na~+)和氯离子(Cl~-)的含量,但同时会显著增加土壤水溶性钙离子(Ca~(2+))及硫酸根离子(SO_4~(2-))含量;随着磷石膏施入量的提高,土壤全盐量呈现先降低后升高的趋势。添加红糖能够间接降低盐碱土壤水溶性Na~+和Cl~-的含量以及全盐量,但不同红糖施入量的处理间并无显著差异。根据试验结果,推荐在施入园林废弃物作为饵料并投放蚯蚓的基础上,同时添加1 kg m~(-2)的磷石膏及0.4 kg m~(-2)的红糖,以取得最佳的降盐效果。 相似文献
10.
磷石膏改良剂对江苏如东滨海盐土理化性状及小麦生长的影响 总被引：9，自引：0，他引：9
江苏沿海地区有大量的滨海盐土,植物难以生长,如能改良,是一种重要的农业资源。本文以如东滩涂滨海盐土为研究对象,采用室内盆栽试验,研究施用磷石膏改良剂对滨海盐土的改良效果。结果表明：磷石膏改良剂能有效的促进小麦的生长,改良剂5的小麦株高比对照2增加47.4%和68.3%,生物量分别增加66.7%和74.4%;随着磷石膏改良剂的用量增加,土壤的养分含量逐渐提高,特别是速效磷,改良剂5比对照1分别增加245.8%和463.4%;土壤盐分由原来的有害氯化钠盐占主导转变为对植物无害的硫酸盐,优化了土壤盐分组合;同时土壤的PH下降,与对照1比,下降幅度分别为7.4%和13.7%,且PH值与磷石膏改良剂的用量呈负相关,说明磷石膏对滨海盐土有很好的改良效果。 相似文献
11.
在总结分析国内有关自然侵蚀量、容许土壤流失量研究成果的基础上,探讨自然侵蚀量与容许土壤流失量的关系,讨论制订水土流失治理标准的思路。认为水土流失治理标准的确定有3个参考值：1）标准值,即一定条件下的容许土壤流失量,是水土流失治理至少要达到的目标,且随着对不同土地利用类型的功能需求与可实施的最佳水土保持措施、以及所在水土流失类型区的侵蚀危害与治理约束条件的不同而不同;2）理想值,即正常自然侵蚀状态下的土壤流失量;3）极端值,即土壤流失量为0,不发生水土流失。水土流失治理应是先控制到现时生态环境与社会经济条件下的容许土壤流失量范围内,逐步达到自然正常侵蚀量或制止水土流失的发生;还应引入环境伦理、环境美学及景观设计等理念,最终实现土地的可持续利用、区域生态系统的健康稳定及人与自然的和谐友好发展。 相似文献
12.
土壤含水率与土壤碱度对土壤抗剪强度的影响 总被引：11，自引：11，他引：11
土壤含水率和土壤碱度是表征土壤物理化学性质的两个重要参数。通过室内三轴不固结不排水试验，研究了土壤含水率和土壤碱度对土壤抗剪强度的影响。试验处理采用5种土壤碱度(土壤可交换钠百分比ESP=0、5、10、20、40)和4种土壤质量含水率(0.05、0.10、0.20以及饱和含水率0.34)水平。试验结果显示，土壤黏聚力随着土壤含水率的增加基本上呈先增大后减小之趋势；当土壤含水率在0.10附近时黏聚力达到其最大值。土壤内摩擦角随着土壤含水率的增加而线性减小。土壤碱度对土壤黏聚力的影响机理较为复杂，其影响效果随土壤含水率的增加而减小；但土壤碱度对土壤内摩擦角的影响较小。土壤碱度对土壤抗剪强度的影响程度明显地小于土壤含水率对其的影响程度。 相似文献
13.
A. M. Globus 《Eurasian Soil Science》2009,42(2):147-150
The results of studies of thermal water transfer and the functional analysis of nonisothermal soil water exchange (summarizing the current concepts of its physical nature, value, relations to soil properties, contribution to heat conductivity, and use for determining other hydrophysical properties of soils) are presented without going into detail of the mathematical analysis. 相似文献
14.
《Communications in Soil Science and Plant Analysis》2012,43(6):367-375
Abstract Soil samples were obtained at 0–3, 3–6, 6–9 and 0–9 inch depths from experimental plots receiving five tillage treatments. Each of two samplers composited approximately six one‐inch cores from each plot. Soil samples were analyzed for acidity, P and K using routine analysis procedures in the University of Illinois Soil Testing Laboratory. Few significant differences were attributed to sampler and it was concluded that samplers using similar sampling techniques were obtaining soil samples from the same population. No significant differences in soil acidity at different depths were observed. The different tillage methods did significantly affect soil P at the 0–3 inch depth, but had no significant effect on soil P at deeper depths. Different tillage methods also significantly affected soil K values at different depths. 相似文献
15.
Theoretical bases are offered for the ecological soil standardization presuming the scientific substantiating of the allowable
ecological state (quality) of the soil and the allowable anthropogenic impact on it. The modern experience of these bases’
application in regulatory-methodological, nature-control, and managerial practices is presented. The criteria are found for
determining the levels of the allowable ecological quality of soil and the anthropogenic impact on it. The sources of the
anthropogenic impact on the soil are characterized. A unified system of indices of soil quality and anthropogenic impacts
and a mechanism for determining the range of the allowable values of these parameters have been developed taking into account
the natural conditions and types of land use. Scientific-methodological approaches are proposed that support a certain balance
between the allowable ecological status of the soil and the effects on it in connection with the mechanisms of the soil quality
control in particular land plots. 相似文献
16.
黑土区土壤侵蚀厚度对土地生产力的影响及其评价 总被引：5，自引：2，他引：3
为了研究黑土区土壤侵蚀厚度对土地生产力的影响,采用盆栽试验,人为剥离黑土表层0、5、10、15、20、25和30 cm土壤以模拟侵蚀厚度不同的耕层土壤,分析土壤侵蚀厚度对土壤理化性质、大豆生物性状和水分利用效率等指标的影响。并对TOPSIS(technique for order preference by similarity to ideal solution)模型进行改进,用于评价侵蚀厚度不同的土壤的土地生产力。结果表明:土壤全N、碱解N、全P、速效P、有机质含量和土壤田间持水率均随侵蚀厚度的增加而递减,土壤容重随侵蚀厚度的增加而递增。土壤侵蚀厚度对大豆生长有显著影响,随着侵蚀厚度的增加,大豆减产率呈"S型"曲线递增,产量、耗水量呈"Z型"曲线递减,水分利用效率呈指数曲线关系递减。改进的TOPSIS模型对不同侵蚀厚度下土地生产力的评价结果较为理想,计算的土地生产力指数随土壤侵蚀厚度的变化呈"Z型"曲线,与大豆产量的变化趋势相同,且二者呈指数函数关系,决定系数达0.996,均方根误差为0.65。研究结果可为黑土区土壤侵蚀防治提供理论依据。 相似文献
17.
18.
Microbial activity is affected by changes in the availability of soil moisture. We examined the relationship between microbial activity and water potential in a silt loam soil during four successive drying and rewetting cycles. Microbial activity was inferred from the rate of CO2 accumulating in a sealed flask containing the soil sample and the CO2 respired was measured using gas chromatography. Thermocouple hygrometry was used to monitor the water potential by burying a thermocouple in the soil sample in the flask. Initial treatment by drying on pressure plates brought samples of the test soil to six different water potentials in the range -0.005 to -1.5MPa. Water potential and soil respiration were simultaneously measured while these six soil samples slowly dried by evaporation and were remoistened four times. The results were consistent with a log-linear relationship between water potential and microbial activity as long as activity was not limited by substrate availability. This relationship appeared to hold for the range of water potentials from ?0.01 to ?8.5 MPa. Even at ?0.01 MPa (wet soil) a decrease in water potential from ?0.01 to ?0.02 MPa caused a 10% decrease in microbial activity. Rewetting the soil caused a large and rapid increase in the respiration rate. There was up to a 40-fold increase in microbial activity for a short period when the change in water potential following rewetting was greater than 5 MPa. Differences in microbial activity between the wetter and drier soil treatments following rewetting to the original water potentials are discussed in terms of the availability of energy substrate. 相似文献
19.
The interaction of soil microbes with their physical environment affects their abilities to respire, grow and divide. One of these environmental factors is the amount of moisture in the soil. The work we published almost 25 years ago showed that microbial respiration was linearly related to soil-water content and log-linearly related to water potential. The paper arose out of collaboration between two young researchers from different areas of soil science, physics and microbiology. The project was driven by not only our curiosity but also the freedom to operate without the constraints common to the current system of science management. The citation history shows three peaks, 1989, 1999 and from 2002 to the present day. Interestingly, the annual citation rate is as high as it has ever been. The initial peak is due to the application of the work to studies on microbial processes. The second peak is associated with the rise of simulation modelling and the third with the relevance of the findings to climate change research. In this article, our paper is re-evaluated in the light of subsequent studies that allow the principle of separation of variables to be tested. This re-evaluation lends further credence to the linear relationship proposed between soil respiration and water content. A scaled relationship for respiration and water content is presented. Lastly, further research is suggested and more recent work on the physics of gas transport discussed briefly. 相似文献
20.
熏蒸处理对土壤微生物及硝化作用的影响 总被引：3，自引：0，他引：3
在田间条件下用溴甲烷(68.1g/m2)、威百亩(7.5mL/m2)进行土壤熏蒸,调查两种药剂对土壤微生物及硝化作用的影响。结果表明:两种熏蒸剂对土壤放线菌无抑制作用,对细菌总量影响较小,但亚硝酸细菌受到强烈抑制,土壤的硝化作用受到明显影响;同时,土壤中真菌的数量及种类变化显著。熏蒸后9周,处理区土壤中的微生物基本恢复正常。 相似文献