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1.
为探讨碳纳米材料对高羊茅生长和蚯蚓生理的影响,在草坪土壤基质中添加3种碳纳米材料(石墨烯、氧化石墨烯和碳纳米管),采用赤子爱胜蚓作为受试生物,研究了施加1%和3%碳纳米材料90 d后高羊茅生长、蚯蚓抗氧化酶活性和丙二醛(MDA)含量的变化。结果表明:不同比例的碳纳米材料对高羊茅的株高、地上鲜质量和干质量均没有显著影响。碳纳米材料均显著抑制了蚯蚓超氧化物歧化酶(SOD)的活性,3%碳纳米管的抑制率达到39.3%;暴露于3%氧化石墨烯,过氧化物酶(POD)活性显著降低;添加1%氧化石墨烯,过氧化氢酶(CAT)活性有所升高,添加3%碳纳米管和3%石墨烯,CAT活性显著低于1%氧化石墨烯处理。此外,碳纳米材料对蚯蚓体内的谷胱甘肽S-转移酶(GST)活性和MDA含量并无明显影响。因此,施加一定浓度的碳纳米材料不会影响草坪植物的生长,但其可以诱导蚯蚓体内活性氧(ROS)的产生,引起抗氧化酶活性发生变化,对土壤动物蚯蚓具有一定的毒性作用。  相似文献   
2.
Effects of earthworm casts on soil nutrient dynamics and their responses to changing moisture availability in subtropical ecosystems remain poorly understood. This study aimed to examine short-term carbon(C) and nitrogen(N) dynamics and their interactions with wetting-drying cycles in three different structural forms(i.e., granular, globular, and heap-like) of Amynthas earthworm casts. The rates of C and N mineralization in the earthworm casts were examined under two different wetting-drying cycles(i.e., 2-d and 4-d wetting intervals) using a rainfall simulation experiment. After three simulated rainfall events, subsamples of the earthworm casts were further incubated for 4 d for the determination of CO_2 and N_2O fluxes. The results of this study indicated that the impacts of wetting-drying cycles on the short-term C and N dynamics were highly variable among the three cast forms, but wetting-drying cycles significantly reduced the cumulative CO_2 and N_2O fluxes by 62%–83% and 57%–85%, respectively, when compared to the control without being subjected to any rainfall events. The C mineralization rates in different cast forms were affected by the amount of organic substrates and N content in casts, which were associated with the food preference and selection of earthworms. Meanwhile, the cumulative N_2O fluxes did not differ among the three cast forms. Repeated wetting and drying of casts not only enhanced aggregate stability by promoting bonds between the cast particles, but also inhibited microbial survival and growth during the prolonged drying period, which together hindered decomposition and denitrification. Our findings demonstrated that the interactions between the structural forms, aggregate dynamics, and C and N cycling in the earthworm casts were highly complex.  相似文献   
3.
蚯蚓养殖对幼龄胶园土壤养分及橡胶树根系生长的影响   总被引:1,自引:0,他引:1  
本研究旨在探讨林下蚯蚓养殖对幼龄胶园土壤养分及橡胶树根系生长的影响。以牛粪作为原料,于 2017年4—11 月在 4 年生幼龄胶园铺设粪垄养殖蚯蚓,并测定土壤养分和根系生长情况。结果表明,与对照(CK)相比,铺设粪垄无蚯蚓养殖(WQ)和铺设粪垄蚯蚓养殖(Q)处理总体上可显著提高土壤硝态氮、速效磷、速效钾和土壤水分含量以及土壤 pH,而对土壤铵态氮、有机质、微生物活性及微生物群系数量无显著影响(p<0.05);和 CK 相比,WQ和 Q 处理显著促进根的生长,并提高吸收根的比例(p<0.05)。综上所述,在幼龄胶园养殖蚯蚓短期内(半年)可提高土壤速效养分含量,促进根系生长。  相似文献   
4.
以两优培九为材料,采用大田微区试验,研究不同氮肥水平(N1,9 g/m~2;N2,12 g/m~2;N3,15 g/m~2)下不同蚯蚓粪施用量(EC0,0;EC_1,16.88 kg/m~2;EC_2,33.76 kg/m~2)对水稻生长及产量形成的影响。结果表明,移栽40 d后EC_2和EC_1处理的茎蘖数均显著高于EC0(P0.05);幼穗分化期和乳熟期EC0处理的SPAD值均显著低于EC_1和EC_2处理(P0.05);齐穗期EC0处理的叶面积指数分别比EC_1和EC_2处理低32.7%和80.7%,地上部总干物质量分别比EC_1和EC_2处理低30.6%和59.8%;成熟期有效穗数、地上部干物质量和水稻产量均表现为EC_2EC_1EC0,EC_2和EC_1处理的有效穗数分别比EC0处理多41.5%和21.3%、地上部干物质量分别比EC0处理高47.7%和25.8%、产量分别比EC0处理高35.4%和34.3%。由此可见,施用蚯蚓粪便可促进水稻分蘖,提高水稻叶面积、SPAD值和地上部干物质量,进而提高水稻籽粒产量。  相似文献   
5.
本研究旨在探讨林下蚯蚓养殖对幼龄胶园土壤养分及橡胶树根系生长的影响。以牛粪作为原料,于 2017 年 4—11 月在 4 年生幼龄胶园铺设粪垄养殖蚯蚓,并测定土壤养分和根系生长情况。结果表明,与对照(CK)相比,铺设粪垄无蚯蚓养殖(WQ)和铺设粪垄蚯蚓养殖(Q)处理总体上可显著提高土壤硝态氮、速效磷、速效钾和土壤水分含量以及土壤 pH,而对土壤铵态氮、有机质、微生物活性及微生物群系数量无显著影响(p<0.05);和 CK 相比,WQ和 Q 处理显著促进根的生长,并提高吸收根的比例(p<0.05)。综上所述,在幼龄胶园养殖蚯蚓短期内(半年)可提高土壤速效养分含量,促进根系生长。  相似文献   
6.
王冰洁  姜蕾  潘波  刘迎  林勇 《热带作物学报》2019,40(9):1804-1809
蚯蚓是土壤健康的关键指示生物,为了更好地评价草甘膦对土壤无脊椎动物的影响,本研究采用土壤法测定草甘膦对蚯蚓的急性毒性;用不同浓度的草甘膦分别测定不同暴露时间下对蚯蚓超氧化物歧化酶、过氧化氢酶、过氧化物酶、谷胱甘肽S转移酶、乙酰胆碱酯酶活性的影响。结果显示,土壤法测定草甘膦对蚯蚓的LC50>1000 mg/kg;在草甘膦的影响下,随着暴露时间的延长,蚯蚓SOD酶活力有着先增高后下降的趋势,CAT酶活力呈现着先下降后升高的趋势,随着时间和浓度的增长POD酶活力在草甘膦的影响下有逐渐下降的趋势;相对于空白对照,处理组AChE酶活力在草甘膦暴露14 d时显著降低。研究结果将为合理评价和监测草甘膦造成的土壤污染水平提供科学依据。  相似文献   
7.
牛粪堆肥成型基质块蔬菜育苗灌溉方式   总被引:3,自引:2,他引:1  
为优选蔬菜育苗成型基质的灌溉方式,提高成型基质蔬菜育苗效果,以牛粪好氧堆肥腐熟料和牛粪蚯蚓堆肥腐熟料为主料配方的成型基质块为研究对象,在低位浸泡灌溉和微喷灌溉条件下,其中牛粪好氧腐熟料成型基质块灌溉耗水量体积的处理水平分别为2 500、350、700、1 050、1 400、1 750 m L,用T1、T2、T3、T4、T5、T6表示;牛粪蚯蚓堆肥腐熟料基质块灌溉耗水量体积的处理水平分别为3 000、700、1 050、1 400、1 750、2 100 m L,用TS1、TS2、TS3、TS4、TS5、TS6表示,探讨不同灌溉条件对2种牛粪腐熟料成型基质块中全氮(TN)、全磷(TP)、全钾(TK)的迁移及其吸水特性和育苗效果。结果表明,2种牛粪腐熟料成型基质块在低位浸泡灌溉下,其灌溉充分,淋洗脱盐量相对较小,并且对成型基质块的冲刷,扰动较小;微喷灌溉最小灌溉量T2或TS2下,虽然其淋洗损失的TN、TP、TK小于低位浸泡灌溉,但成型基质块未能被充分湿润,影响育苗效果;微喷灌溉在T3、T4、T5、T6或TS3、TS4、TS5、TS6处理水平下,成型基质块中的TN、TP、TK淋洗损失量均大于低位浸泡灌溉,并且随灌溉量的增大而逐步增大。对牛粪好氧堆肥腐熟料成型基质块,育苗前期应选取微喷灌溉T4进行前充分淋洗,育苗后期采取低位浸泡灌溉保留幼苗生长所需养分;而对牛粪蚯蚓堆肥腐熟料成型基质块,TS1处理下黄瓜幼苗的茎粗(6.23 mm)、株高(138.09 mm)、地上部分干质量(758.85 mg)、地下部分干质量(147.92 mg)和壮苗指数(217.64)均为该试验中最大值,灌溉水利用率为2.79g/kg,该处理水平下幼苗生长及水分有效利用率均较优,即可采取TS1处理对牛粪蚯蚓腐熟料成型基质块进行灌溉。  相似文献   
8.
Vermicomposting is an efficient and environmentally friendly technology to dispose of agricultural organic residues. The efficiency of organic residue decomposition during vermicomposting is directly affected by the biomass and population structure of earthworms. In this study, we investigated how the earthworm biomass and population structure responded to changes in the physicochemical properties of six types of organic residue (cattle dung, herbal waste, rice straw, soybean straw, garden waste, and tea residues) during vermicomposting. Each type of organic residues was placed in a pot with earthworms Eisenia fetida, and the physicochemical properties of the organic residues and earthworm growth dynamics were recorded at 0, 30, 60, and 90 d of vermicomposting. The biomass and population structure of earthworms were stable or increased in rice straw, garden waste, and cattle dung within 60 d of vermicomposting, whereas in tea residues and herb waste, very little earthworm activity (3 adults and 2 cocoons) was recorded on day 30. Among the physicochemical parameters, the substrate C/N ratio was negatively correlated with earthworm growth dynamics. Decomposing organic residues showed higher NH4+-N and NH3--N concentrations but a lower total organic carbon content, which negatively affected earthworm growth and reproduction. We recommend that chemical properties of vermicomposting systems should be monitored regularly. At the threshold levels of decomposing organic residue NH4+-N and NH3--N concentrations, earthworms should be removed and the vermicompost can be harvested. Small- and large-scale farmers thus need to monitor the physicochemical properties of vermicompost to sustain active earthworm populations.  相似文献   
9.
山东半岛与辽东半岛蚯蚓生物多样性研究   总被引:2,自引:1,他引:1  
于2009年在我国的山东半岛和辽东半岛地区采用挖掘法对这些地区不同类型生境采集到的蚯蚓的生物多样性进行了系统调查。野外采集到的蚯蚓置于潮湿土壤带回驻地,在采集当日用70%酒精处死,保存于95%酒精以备研究。部分形态分类特征明显的蚯蚓个体作为模式标本保存于10%福尔马林溶液。本研究据此提供了该地区最新的蚯蚓资源名录。在山东半岛发现陆栖蚯蚓3科6属13种,以巨蚓科(占种类总数的39%)、正蚓科(占种类总数的39%)为主;在辽东半岛调查共发现3科7属16种,以正蚓科(占种类总数的44%)、巨蚓科(占种类总数的31%)为主。作为蠕虫养殖业中的赤子爱胜蚓,在野外环境中也有分布。  相似文献   
10.
In structured soils, water and reactive solutes can preferentially move through larger inter‐aggregate pores, cracks, and biopores. The surface roughness of such macropores is crucial for describing microbial habitats and the exchange of water and solutes between macropores and the soil matrix together with other properties. The objective of this study was to compare the roughness of intact structural surfaces from the Bt‐horizons of five Luvisols developed on loess and glacial till and to test the applicability of confocal laser scanning microscopy. Samples of 5 to 10 cm edge length with intact structural surfaces including cracks with and without clay‐organic coatings, earthworm burrow walls, and root channels were prepared manually. The surface roughness of these structures was determined with a confocal laser scanning microscope of the type Keyence VK‐X100K. The root‐mean‐squared roughness (Rq) the curvature (Rcu) and the ratio between surface area and base area (RA) were calculated from selected surface regions of interest of 0.342 mm2 with an elevation resolution of 0.02 µm. The roughness was smaller for coated as compared to uncoated cracks and earthworm burrows of the Bt‐horizons. This reduction of roughness by the illuviation of clayey material was similar for the structural surfaces of the coarser textured till‐Bt and the finer‐textured loess‐Bt. This similarity suggested a dominant effect of pedogenesis and a minor effect of the parent material on the roughness levels of structural surfaces in the Bt‐horizons. An expected “smoothing” effect of burrow wall surfaces by earthworm activity was not reflected in the roughness values compared to those of uncoated cracks at the chosen spatial scale. However, for root channel walls from one loess‐Bt, the roughness was reduced as compared to that of other structures. These results suggest that the surface roughness of the structural surface types should separately be considered when describing preferential flow and macropore‐matrix exchange or analysing root growth, microbial habitats, and colloidal transport in structured soils. The confocal laser scanning microscopy technique was found useful for characterizing the roughness of intact structural surfaces.  相似文献   
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