不同有机物料培肥对渭北旱塬土壤微生物学特性及土壤肥力的影响

通过田间试验,研究了施用不同有机物料对渭北旱塬耕地土壤微生物学特性及土壤肥力的影响。结果表明,化肥与不同有机物料配合施用,土壤微生物学特性［微生物量碳（MBC）、微生物量氮（MBN）、脲酶、碱性磷酸酶］以及部分土壤养分状况（全氮、速效磷、速效钾、阳离子交换量）比单施化肥处理均得到进一步改善。化肥配施秸秆堆肥处理效果最明显,其中微生物量碳增加了41.96%,微生物量氮增加了54.55%,脲酶活性增加了19.71%,碱性磷酸酶活性增加了7.35%,速效磷增加了63.12%;而且土壤微生物量碳、氮与速效磷、阳离子交换量呈显著正相关,微生物商（qMB）、脲酶活性、碱性磷酸酶活性与全氮、速效氮、速效钾含量呈显著相关;同时SMBC、SMBN、qMB等与作物产量密切相关（相关系数分别为0.85,0.74,0.82）。因此,化肥配施秸秆堆肥处理在渭北旱地雨热条件下对于全面提升土壤质量具有重要的意义;同时该区域土壤中微生物量碳氮与土壤养分状况、作物产量具有很好的一致性,可以表征土壤肥力状况及生产力水平。     

连续施用无害化污泥对沙质潮土土壤肥力和微生物学性质的影响

以小麦-玉米轮作体系下的沙质潮土为研究对象,选用经无害化处理后的城市污泥产物,通过2013~2015年田间定位试验,研究了不同城市污泥施用量对土壤肥力的影响,以期为城市污泥资源化利用提供理论基础和技术依据。设置单施化肥(CK)、CK+污泥15 t·hm~(-2)(CS1)、CK+污泥30 t·hm~(-2)(CS2)和CK+污泥45 t·hm~(-2)(CS3)共4个处理。主要研究结果如下:(1)连续定位试验结果表明,同一施用量污泥处理的土壤p H值随施用时间的增加呈下降趋势;土壤有机质(SOM)和养分含量如全氮(TN)、有效磷(AP)和速效钾(AK)随施用时间的增长呈上升趋势;(2)与CK比较,在2015年玉米季施用污泥各处理的土壤p H值显著降低了0.34~0.83个单位(P0.05),且与污泥施用量呈反比,以高施量污泥45 t·hm~(-2)下降最多;土壤SOM、TN、AP和AK分别显著提高了52.1%~166.9%、77.3%~177.8%、215.7%~486.3%和167.2%~379.0%(P0.05),且与污泥施用量呈正比,以高施量污泥45 t·hm~(-2)效果最显著;(3)试验所用污泥施用量范围内不会造成土壤和植物籽粒重金属污染,能够保持土壤环境健康;(4)与CK比较,施用污泥各处理土壤微生物量碳(MBC)、氮(MBN)含量均显著提高(P0.05),且与污泥施用量呈正比,并且季节不同也显著影响土壤MBC、MBN含量(P0.05);施用污泥能够显著提高土壤MBC/MBN(P0.05),说明施用污泥能够改变土壤微生物群落组成;(5)施用污泥,尤其是高施量污泥45 t·hm~(-2),在保证土壤和植物籽粒质量安全下,其土壤培肥效果最优。     

紫云英与化肥配施对稻田土壤养分和微生物学特性的影响

在安徽沿江双季稻区,通过4年田间定位试验研究了不同用量紫云英绿肥与化肥配施对水稻产量、土壤肥力和土壤微生物数量及活度的影响。结果表明,施用紫云英绿肥比不施肥增产40.75%~92.10%,比单施化肥处理增产26.30%~36.49%;与纯施化肥相比较,施用紫云英处理的微生物总量增加了48.26%~115.78%,微生物活度增加了5.88%~29.41%,且施用紫云英土壤全N、碱解N、有效P、速效K和有机质含量均较高。简单相关分析表明,土壤微生物特性与土壤全N、碱解N之间具有极显著的相关性。施肥土壤有机质含量与细菌总数之间无直接相关性,而与真菌、放线菌数量及微生物活度正相关。土壤微生物及土壤养分分析发现,化肥量70%与紫云英22 500 kg·hm-2配施比较适宜于安徽沿江双季稻区早稻生产。     

湿地土壤质量退化的模糊综合评价

Due to frequent soil Cd contamination and wide use of butachlor in China,there is a need to assess their combined toxicity to soil microorganisms.The combined effects of cadmium (Cd,10 mg kg^-1 soil) and herbicide butachlor (10,50,and 100 mg kg^-1 soil) on enzyme activities and microbial community structure in a paddy soil were assessed using the traditional enzyme assays and random amplified polymorphic DNA (RAPD) analysis.The results showed that urease and phosphatase activities were significantly reduced by high butachlor concentration (100 mg kg^-1 soil).When the concentrations of Cd and butachlor added were at a ratio of 1:10,urease and phosphatase activities were significantly decreased whereas enzyme activities were greatly improved at the ratio of 1:5,which indicated that the combined effects of Cd and butachlor on soil urease and phosphatase activities depended largely on their addition concentration ratios.Random amplified polymorphic DNA (RAPD) analysis showed loss of original bands and appearance of new bands when compared with the control soil.Random amplified polymorphic DNA fingerprints suggested substantial differences between the control and treated soil samples,with apparent changes in the number and size of amplified DNA fragments.The addition of high concentration butachlor and the combined impacts of Cd and butachlor significantly affected the diversity of the microbial community.RAPD analysis in conjunction with other biomarkers such as soil enzyme parameters would prove a powerful ecotoxicological tool.Further investigations should be carried out to understand the clear link between RAPD patterns and enzyme activity.     

Pseudomonas putida improved soil enzyme activity and growth of kasumbha under low input of mineral fertilizers

Effective management of the nutrients and enzyme activity in the soil is necessary for maximum crop growth and productivity. However, the excessive use of chemical fertilizers (CFs) not only adversely affects the soil nutrient status and soil physicochemical properties but also aids pollution to the ecosystem. The objective of present study was to investigate the effect of single as well as combined applications of phosphate-solubilizing bacteria and agrochemicals on important soil enzyme activities and their impact on the growth of kasumbha (safflower). Pseudomonas putida (P. putida;10⁶ cells/mL) was applied as seed inoculation prior to sowing, and CFs were applied as full, half, and quarter doses during sowing to modulate the growth of kasumbha host plants. P. putida in combination with half dose of CFs (PH) increased the soil urease and phosphatase activities, while P. putida combined with quarter dose of CFs (PQ) augmented the soil invertase activities. Moreover, the PQ treatment exhibited the maximum colony-forming units of P. putida. Leaf chlorophyll, carotenoids, protein contents, and root lengths were increased by PH treatment. Whereas, shoot length and leaf area were improved by PH and PQ treatments, respectively. Leaf protease activity was enhanced by P. putida in combination with full dose of CFs and PQ treatments, while leaf phosphate contents were significantly improved by PQ treatment. It can be concluded that P. putida in combination with half as well as quarter doses of CFs is a promising approach for the improvement of soil enzyme activities and growth of kasumbha and replacing 50% of the use of CFs.     

五爪金龙、 南美蟛蜞菊入侵对土壤化学和微生物学性质的影响

【目的】五爪金龙(Ipomoea cairica)、 南美蟛蜞菊(Wedelia trilobata)已入侵我国华南地区并造成严重危害。本文研究了五爪金龙入侵群落、 南美蟛蜞菊入侵群落与土著植物类芦(Neyraudia reynaudiana)群落内的土壤养分、 土壤微生物量、 土壤酶活性以及微生物群落代谢活性、 碳源利用特征与功能多样性的变化规律,探讨两种外来植物入侵对土壤生态系统的影响,为揭示其野外入侵机制提供科学依据。【方法】采用野外样方法于2010年1月在广州市东郊的火炉山森林公园设置五爪金龙入侵区、 南美蟛蜞菊入侵区和土著植物类芦区3类样地,测定土壤养分、 土壤酶活性、 土壤微生物量与微生物功能多样性。【结果】1)与土著植物区相比,五爪金龙入侵区土壤有机碳、 全氮、 全磷以及速效氮、 速效磷、 速效钾含量显著提高,增幅达到60.38%~230.01%; 南美蟛蜞菊入侵区土壤有机碳、 全氮、 速效氮、 速效磷含量亦显著提高,增幅达到50.54%~145.52%; 两种外来植物入侵区土壤C/N比显著降低,但对全钾含量的影响不明显。2)两种外来植物能够显著提高入侵地的土壤微生物量,其中五爪金龙、 南美蟛蜞菊入侵区的土壤微生物量碳(Cmic)、 氮(Nmic)、 磷(Pmic)含量分别比土著植物区增加105.00%~152.15%和61.51%~138.27%,但土壤微生物量在两个入侵区之间的差异不明显; 对于土壤微生物熵,南美蟛蜞菊入侵区的Cmic/Corg值显著高于土著植物区,但Nmic/Nt、 Pmic/Pt值3类样地之间差异不显著。3)两种外来植物入侵显著提高土壤脲酶、 蛋白酶、 蔗糖酶和纤维素酶的活性,其中南美蟛蜞菊入侵区的土壤脲酶、 蛋白酶和纤维素酶活性最高,分别比土著植物区增加70.35%、 21.51%和227.86%; 对于蔗糖酶活性,五爪金龙、 南美蟛蜞菊入侵区的增幅则分别达到322.58%和157.14%; 过氧化氢酶活性各处理间的差异较小,差异均不显著。4)两种外来植物入侵能够提高土壤微生物群落的代谢活性,平均孔颜色变化率(AWCD)在整个培育周期内均表现为五爪金龙入侵区＞南美蟛蜞菊入侵区＞土著植物区,其中72 h的AWCD值分别为1.18、 0.88和0.56,差异显著。与土著植物区相比,五爪金龙入侵区6种类型碳源的利用效率显著提高,其增幅高达75.00%~162.86%; 南美蟛蜞菊入侵区碳水化合物类、 羧酸类和聚合物类碳源的利用率亦显著提高,其增幅分别为87.72%、 41.18%和83.72%; 两种入侵植物对不同类型碳源的利用程度存在一定差异,五爪金龙对羧酸类、 胺类碳源的利用率显著高于南美蟛蜞菊。主成分分析显示,PC1与PC2能够解释不同入侵区土壤微生物群落碳源利用数据71.89%的总体变异,其中PC1主要受碳水化合物类、 氨基酸类与聚合物类碳源的影响,PC2则主要受碳水化合物类与羧酸类碳源的制约。两种外来植物入侵对土壤微生物群落的功能多样性产生重要影响,其中入侵地土壤微生物群落的Shannon-Wiener指数(H)、 Mc Intosh指数(U)、 丰富度指数(S)和Simpson优势度指数(Ds)显著高于土著植物区,但两个入侵区之间的差异较小; 三个处理区的Pielou均匀度指数(E)差异不明显。【结论】五爪金龙、 南美蟛蜞菊两种外来植物能够改善入侵地的土壤营养环境,提高土壤肥力水平,形成对自身生长、 竞争有利的微环境,从而加快入侵扩散。     

Sewage sludge treated with bentonite,vermiculite or biochar can improve soil properties and enhance growth of grasses

Sewage sludge treated with 15% bentonite, vermiculite or biochar was evaluated as a soil amendment in comparison to limed and untreated sludge. Seven treatments were established to two soils, an acid and an alkaline, in three replications, i.e. 2% addition of sludge treated with bentonite, vermiculite, biochar and lime and application of 2% untreated sludge, inorganic fertilization and no sludge or inorganic fertilizers (control). Then, the soil treatments were used in a pot experiment with perennial ryegrass (Lolium perenne L.) as a test plant. Sludge treated with the clay minerals or biochar improved pH of the acid soil and significantly increased organic matter and available nutrients of both soils compared to control. Although no salinity or sodicity hazard was evidenced, the initial salinity of acid and alkaline soil increased by four-eight and two-three times, respectively, upon addition of all sludge treatments, especially that of untreated sludge. Moreover, soil available zinc (Zn) increased by four-eight times. Soil application of sludge treated with the clay minerals or biochar increased the total aboveground biomass yield of ryegrass in the acid and alkaline soil by 133%–171% and 72%–88%, respectively, compared to control and enhanced nutrient uptake by plants. Furthermore the microbial metabolic quotient indicated lack of low pH and heavy metal stress with addition of sludge to the acid soil. After three harvests of ryegrass, the residual effect of sludge on pH of acid soil and salinity, available phosphorus (P), Zn and boron (B) of both soils still persisted. Thus sewage sludge treated with 15% bentonite, vermiculite or biochar could be applied to soils at a rate of 2% (≈80 Mg ha⁻¹) to serve as soil amendment and fertilizer for grasses and pasture species; however, caution is needed regarding possible P build-up, Zn phytotoxicity and salinization risks.     

An overview on biochar production, its implications, and mechanisms of biochar-induced amelioration of soil and plant characteristics

The degradation of soil fertility and quality due to rapid industrialization and human activities has stimulated interest in the rehabilitation of low-fertility soils to sustainably improve crop yield. In this regard, biochar has emerged as an effective multi-beneficial additive that can be used as a medium for the amelioration of soil properties and plant growth. The current review highlights the methods and conditions for biochar production and the effects of pyrolysis temperature, feedstock type, and retention time on the physicochemical properties of biochar. We also discuss the impact of biochar as a soil amendment with respect to enhancing soil physical (e.g., surface area, porosity, ion exchange, and water-holding capacity) and chemical (e.g., pH, nutrient exchange,functional groups, and carbon sequestration) properties, improving the soil microbiome for increased plant nutrient uptake and growth, reducing greenhouse gas emissions, minimizing infectious diseases in plants, and facilitating the remediation of heavy metal-contaminated soils. The possible mechanisms for biochar-induced amelioration of soil and plant characteristics are also described, and we consider the challenges associated with biochar utilization. The findings discussed in this review support the feasibility of expending the application of biochar to improve degraded soils in industrial and saline-alkali regions, thereby increasing the usable amount of cultivated soil. Future research should include long-term field experiments and studies on biochar production and environmental risk management to optimize biochar performance for specific soil remediation purposes.     

Effect of biochar and phosphorus fertilizer application on soil fertility: soil physical and chemical properties

This study evaluated the effect of biochar and phosphorus fertilizer application on selected soil physical and chemical properties in two contrasting soil types: Rhodic Ferralsols (clay) in Thohoyandou and Leptic Cambisols (loamy sand) in Nelspruit, South Africa. Field experiments were conducted in summer and winter. Treatments consisted of a factorial combination of four biochar levels (0, 5, 10 and 20 t ha^?1) and two phosphorus fertilizer levels (0 and 90 kg ha^?1) arranged in a randomized complete block design with three replicates. Chickpea was the test crop. Soil bulk density, aggregate stability, porosity, total C, total N, C:N ratio, K and Mg were determined. Biochar (10 t ha^?1) and phosphorus increased bulk density and decreased porosity at 0–5 and 15–20 cm soil depth on a loamy sand soil in both seasons. The interaction between biochar and phosphorus increased total C and total N on a clay soil in the summer sowing. However, in the loamy sand soil, biochar (10 t ha^?1) increased total C, C:N ratio, K and Mg in the summer sowing. The effect of biochar was more evident in the loamy sand soil than the clay soil suggesting that the influence of biochar may be soil-specific.     

封育对退化草原植被恢复及土壤理化性质影响的研究进展

封育是退化草原生态系统恢复的有效措施之一。在梳理现有封育研究成果的基础上,归纳封育对植物多样性、生物量、植被演替、土壤物理与化学性状的影响效应,发现:受地理区域、气候条件及封育前退化程度等本底条件的影响,封育条件下植被多样性呈现出显著增加、基本稳定和明显下降3种结果,生物量则表现为围封初期增加,围封时间过长不利于维持较高生物量的变化趋势;封育使得种群拓殖能力与群落资源冗余,土壤种子库结构改善、密度增长,退化草原呈正向演替,并可能出现3种演替模式。封育消除了土壤紧实层,改善了土壤结构与性状,但对土壤养分的影响效应不一致。基于研究现状,提出今后应深入研究的6个内容与方向,对丰富封育条件下退化草原恢复效应具有指导意义。     

Short-term effects of biochar and gypsum on soil hydraulic properties and sodicity in a saline-alkali soil

Salt and sodicity of saline-alkali soil adversely affect the construction of ecological landscapes and negatively impact crop production. The reclamation potential of biochar (BC, wheat straw biochar applied at 1% by weight), gypsum (G, 0.4% by weight), and gypsum coupled with biochar (GBC) was examined in this laboratory-based study by evaluating their effects on a saline-alkali soil (silt loam) with no amendment as a control (CK). Saline ice and fresh water (simulated rainfall) were leached through soil columns to investigate changes in salt content, sodium adsorption ratio (SAR), alkalinity, and pH of the leachate and the soil. Results showed that saturated water content and field water capacity (FWC) significantly increased by 4.4% and 5.6%, respectively, in the BC treatment after a short incubation time. Co-application of biochar and gypsum (GBC) increased soil saturated hydraulic conductivity (Ks) by 58.4%, which was also significantly higher than the sole addition. Electrical conductivity (EC) of the leachate decreased sharply after saline ice leaching; subsequent freshwater leaching accelerated the removal of the rest of the salts, irrespective of the amendment application. However, the application of gypsum (G and GB) significantly enhanced the removal of exchangeable Na+ and reduced leachate SAR. After leaching, the soil salt content decreased significantly for all treatments. The application of gypsum resulted in a significantly lower soil pH, exchangeable sodium percentage (ESP), SAR, and alkalinity values than those recorded for the CK and BC treatments. These results demonstrated that the co-application of gypsum and biochar could improve saline-alkali soil hydraulic conductivity and decrease leaching-induced sodicity over a short period.     

Short-term effects of biochar amendment on soil microbial community in humid tropics

Biochar is known to ameliorate soil fertility and improve crop production but information regarding soil microbiota responses on biochar amendment remains limited. The experiment was conducted to study the effect of biochars from palm kernel (pyrolysed at 400°C) and rice husk (gasified at 800°C) in a sandy loam Acrisol from Peninsular Malaysia. The soil was amended with palm kernel shell biochar (PK), rice husk biochar (RH), palm kernel biochar with fertilizer (FPK), rice husk biochar with fertilizer (FRH), fertilizer and control soil. Soil samples were taken during maize harvesting and were analysed for physico-chemical properties, microbial biomass, microbial abundance and microbial diversity. Increase in pH, moisture content, CEC, organic C, and labile C were recorded in all biochar amended soils. Microbial biomass C was 65% and 36% higher in RH and FRH, respectively, than control. Microbial biomass N was greatest in FPK and FRH with respective increment of 359% and 341% than control. β-glucosidase and xylanase activities were significantly increased in all biochar treated soils than control. A shift in microbial diversity was not detected. The biochar affects the microbial community by altering the soil environment and increasing labile active carbon sources in the short-term amendment.     

玉米秸秆炭还田对黑土土壤肥力特性和氮素农学效应的影响

【目的】探索玉米秸秆炭对东北黑土土壤肥力特性和氮素农学效应的影响,可为东北玉米集约化生产区秸秆资源利用和培肥土壤提供理论和实际应用基础。【方法】本研究以东北典型黑土区春玉米种植体系为研究对象,通过连续两年的田间原位试验,研究了添加500℃厌氧条件热解的玉米秸秆炭对土壤养分含量、 微生物和酶活性的影响及玉米秸秆炭对作物产量和氮素农学效应的影响。试验设三个处理: 1)PK+4 t/hm2秸秆还田(CK); 2)NPK+4 t/hm2秸秆还田; 3)NPK+4 t/hm2秸秆还田+2 t/hm2秸秆生产秸秆碳,在玉米成熟期取020 cm土壤样品和植株样品,采用常规方法进行相关项目的测定。【结果】 1)土壤养分分析结果。与秸秆还田相比,秸秆炭处理在2013和2014年土壤碱解氮含量(AN)分别提高了10.1%和9.7%,均达到显著水平(P0.05); 土壤速效磷含量(AP)分别提高了13.7%和27.3%,在2014年达到显著水平(P0.05); 土壤微生物量碳含量(SMBC)分别提高了13.5%和26.9%,土壤脲酶活性(URE)分别提高了22.3%和31.8%,2014年SMBC和URE升高均达显著(P0.05)。秸秆炭对土壤有机质(OM)、 全氮(TN)、 速效钾(AK)、 土壤微生物量氮(SMBN)和蔗糖酶活性(SUC)的提升效果在两年试验中均没有达到显著水平, 2)氮素农学效应影响结果。与处理2相比,处理3肥料氮偏因子生产力(PFPN)分别提高了3.3%和9.6%,肥料氮经济效益(EBN)分别提高了12.9%和27.5%,均在2014年表现出显著提高(P0.05); 而两年间处理3的玉米产量分别提高3.3%和9.5%、 肥料氮利用率(UEN)分别提高了3.9%和14.0%、 肥料氮农学效率(AEN)分别提高了11.6%和23.9%,但均未达显著水平。【结论】2年试验初步表明施用玉米秸秆炭可以提高土壤微生物活性和土壤酶活性,调节土壤与作物之间的养分供需,改善土壤养分状况,对提升氮素农学效应有作用。因此,玉米秸秆炭可作为秸秆资源高效利用的有效形式,其长期效果还需进一步试验。     

不同施肥处理对土壤微生物学特性和作物产量的影响

采用不同施肥处理试验,分析土壤脲酶、纤维素酶、土壤微生物数量和作物产量的变化,以探索可提高土壤微生物学特性和作物产量的施肥方式。结果显示:土壤脲酶、土壤纤维素酶均表现为施肥处理显著高于不施肥对照(p<0.05)。T5(常规氮磷钾肥+秸秆+秸秆腐熟剂)处理的微生物数量测定结果在两季中与其它处理相比略有增加。小麦产量以T5处理最高,比对照增产38.2%,而玉米产量最高的处理是T3(0.7倍常规氮磷钾肥+有机肥),比对照增产29.2%。相关分析得出,在本试验条件下,两种土壤酶活分别与产量和微生物数量有一定相关性,其中土壤脲酶和土壤纤维素酶可在一定程度上反映土壤肥力,而土壤脲酶在一定程度上可反映土壤微生物数量。综合以上结果,在本实验条件下,T5是最佳的施肥方式。     

Microbial community structure and relationship with physicochemical properties of soil stockpiles in selected South African opencast coal mines

At present, there is no comprehensive soil quality assessment practice for soil stockpiles in the South African coal mining industry. Soil microorganisms and enzymes are suitable indicators for soil quality monitoring. Therefore, this study investigated the microbial community and enzyme (beta-glucosidase and urease) activities in soil stockpiles of opencast coal mines in the coal-rich region of South Africa. Soil stockpiles of three opencast coal mines were sampled at depths of 0–20 cm (‘topsoil’) and >20 cm (‘subsoil’) across three seasons. Beta-glucosidase and urease activities were mostly higher in soil stockpiles than in unmined soils and were significantly influenced (P < 0.05) by the interaction of site and seasonal factors. However, analyses of PCR-denaturing gradient gel electrophoresis (PCR-DGGE) profiles of partial 16S rRNA gene and internally transcribed spacer 2 (ITS2) sequences revealed higher microbial diversity in unmined (reference) soils compared to soil stockpiles across all seasons. Redundancy analysis further revealed that microbial communities of topsoil were not significantly (P > 0.05) influenced by soil properties, whereas microbial communities of subsoils were significantly (P < 0.05) influenced by pH, organic carbon, total nitrogen and phosphorus contents. Furthermore, operational taxonomic units (OTUs) belonging to genera of known phytobeneficial species such as Azomonas, Aureobasidium, Phialocephala, Phoma and Sordariomycetes were detected in these soils. Overall, results suggest that the microbial community structure and diversity observed in stockpiles is impaired (compared to the unmined site), although variations in the microbial community structure of soil stockpiles across seasons are site-specific. The impaired microbial community of stockpiles may have negative implications on soil biological processes driven by microbes; especially those that are critical for nutrient cycling and ecosystem sustainability. More importantly, such alteration in soil biodiversity may impair post-mining land use capability of stockpile soils.     

复垦土壤细菌群落结构及其与土壤肥力的关系

为了解两淮煤矿区复垦状况及其对土壤微生物的影响机制,合理人工干预,快速有效提高复垦土壤生产力,本研究以煤矸石充填复垦土壤为研究对象,通过野外调查与采样分析,采用Illumina MiSeq 高通量测序分析土壤细菌特定基因片段V4 区域,基于非度量多维尺度分析、冗余分析、方差分析、肥力指数、回归模型方法,对矸石充填土壤不同复垦方向的土壤细菌优势群落和生物多样性进行了探索,明晰土壤细菌群落及其与土壤肥力的响应作用。研究结果表明：细菌群落组成上,不同复垦方向对细菌优势群落分布并无显著性影响,变形菌门、酸杆菌门和放线菌门菌群为主要优势菌群。土壤微生物多样性层面上,表层土壤微生物有较高的丰富度和多样性,均匀度并无显著性差异。微生物多样性在不同复垦方向不存在显著性差异,Shannon_Wiener指数介于6.19～6.85之间,Chao1指数为3131.97～4938.37,Pielou指数介于0.79～0.84之间,表中层同深层土壤的细菌群落结构具有差异性。TN、SOM、AP和AK是影响土壤细菌群落的主要肥力因子,土壤肥力质量指数与奇古菌门相对丰度呈显著正相关（P＜0.01）,同链霉菌属呈显著负相关（P＜0.05）,在一定程度上可将二者的相对丰度作为评价复垦土壤肥力状况的重要生物指标。研究成果可为两淮矿区矸石充填复垦土壤在微生物层面提高肥力质量提供理论支持。     

The interactive effects of biochar and cow manure on rice growth and selected properties of salt-affected soil

Salt-affected soil induces detrimental influences on paddy rice (Oryza sativa L.) growth and ameliorating the influences could be done with organic amendments, such as animal manure and biochar. The aims of the current study are: (1) to examine the interactive effects of biochar and cow manure on rice growth and on selected properties of salt-affected soil, and (2) to identify potential mechanisms related to the amendments. Saline-sodic soil was used for a net house experiment with two experimental factors: biochar (no-biochar, rice-husk, and -straw biochar) and cow manure (with and without cow manure). Without the manure, addition of both rice-hush and – straw biochar significantly increased rice growth, whereas a combination of individual biochar with manure did not show a positive synergistic effect. The interactive effect of two factors was not significant on available P and exchangeable K concentrations, but the main effects of the two factors were significant. Biochar addition resulted in higher soil cation exchange capacity (CEC) (28.8 to 29.0 cmol_c kg^?1) than the control (25.6 cmol_c kg^?1), but manure addition did not. Improved nutrient availabilities such as P and K, as well as CEC are among the potential mechanisms accounting for the enhanced rice growth with biochar.     

复合微生物肥对碱土生物学性状与土壤肥力的影响

为探讨复合微生物肥对碱土的改良效果,对内蒙古农业大学海流图科技园区碱土试验地开展了施用复合微生物肥的田间试验,探讨了其对土壤生物学性状和土壤肥力的影响.结果表明:施用复合微生物肥处理较不施肥处理显著降低了耕层土壤pH和EC值,分别降低0.32～0.88个单位和0.17～0.39 mS/cm;显著提高了土壤酶活性、微生物...     

土壤性质对真菌温度敏感性的影响

通过伽马灭菌的方式,将两种不同性质的土壤(自然土和农田土)进行灭菌,再互相接种未灭菌土壤,研究了改变土壤性质对真菌温度敏感性的影响。结果表明,改变土壤性质虽显著影响真菌总丰度,但对真菌总丰度的温度敏感性无显著性影响。然而,部分土壤真菌个体(分类操作单元OTU)对温度具有敏感性,改变土壤性质会对温度敏感真菌个体产生影响。首先,改变土壤性质使自然土壤真菌中的热响应真菌目的个数由2减少为1,使农田土壤真菌中的冷响应真菌目的个数由5增加到9;其次,升温使自然土壤的真菌在自然土壤中冷响应和热响应真菌累积相对丰度之和从2.22%减少为1.35%,在农田土壤中从1.25%减少为0.56%;升温使农田土壤的真菌在农田土壤中冷响应和热响应真菌累积相对丰度之和从13.66%增加到19.03%,在自然土壤中从6.01%减少为2.51%;再次,改变土壤性质使自然土壤的热响应真菌由Capnodiales、Chaetothyriales变为Eurotiales,农田土壤的热响应真菌由Capnodiales、Sordariales变为Chaetothyriales、Hypocreales;自然土壤的冷响应真菌由Chaetosphaeriales、Sordariales等变为Capnodiales、Hypocreales等,农田土壤的冷响应真菌由Chaetothyriales、Eurotiales等变为Capnodiales、Sordariales等;最后,各真菌在目水平上的相对丰度变化率也各不相同。本研究表明,改变土壤性质可显著影响真菌群落结构的温度敏感性,进而可能改变真菌功能的温度敏感性。