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1.
强化型EM菌剂对金针菇菌糠堆肥的影响 总被引:1,自引:0,他引:1
为提高EM菌剂在菌糠堆肥中的应用效果,加速腐熟进程,改善堆肥质量,采用纤维素酶与木聚糖酶高产菌株黑曲霉SNH-7、蛋白酶高产菌株枯草芽孢杆菌SNK-103与EM菌剂进行复配,研制强化型EM菌剂,并研究其对菌糠堆肥的影响。结果表明:与普通EM菌剂相比,接种强化型EM菌剂的处理堆肥过程中微生物代谢更加旺盛,温度、pH、EC值、总有机碳、可溶性有机碳、总氮、铵态氮、硝态氮、C/N、腐植酸和黄腐酸含量等理化指标的升高或降低幅度更大,腐熟进程加快;成品堆肥的GI提高,C/N降低,总氮、硝态氮、总腐植酸和游离腐植酸的含量升高,生物安全性更好、肥效更高。说明在EM菌剂中补充纤维素酶、木聚糖酶和蛋白酶高产菌株,可强化其对纤维素、木质素和蛋白质的降解能力,在无辅料、高C/N、低pH的不利条件下,添加该菌剂能加速堆肥进程,提高堆肥质量。 相似文献
2.
喀斯特断陷盆地是我国石漠化综合治理8大喀斯特类型中治理成效最低、治理难度最大的区域,面临石漠化严重、干旱频发、植被恢复难等突出问题。文中针对水分是影响喀斯特断陷盆地石漠化治理与植被恢复成效最关键的限制因素,综合分析了国内外水分梯度差异与植物群落构建机制研究动态与发展趋势;提出利用日趋成熟的水分脆弱性评价方法,通过建立基于耦合暴露度、敏感性及适应性的水资源脆弱性评价指标体系,以满足遥感影像分辨率和植物群落调查样地大小的评价单元进行水分脆弱性评估;在建立物种库—功能性状—生境特征数据库的基础上,提出基于功能性状差异进行喀斯特断陷盆地植物群落机制构建的研究方案。提出的研究方案有望解决喀斯特断陷盆地石漠化区水分梯度特征与分布格局、自然植物群落组配规律及其生境特征、水分梯度与生境要素对植物群落特征及功能性状组成的影响规律等关键科学问题,可为不同脆弱生态区植被恢复群落构建机制研究提供重要参考和借鉴。 相似文献
3.
耕作方式及秸秆还田对土壤性质、微生物碳源代谢及小麦产量的影响 总被引:1,自引:0,他引:1
以小麦品种济麦22为试验材料,采用裂区试验设计,耕作方式为主区,分别设常规翻耕(C)、深松(S)、旋耕(R)处理,副区为秸秆还田量,分别设秸秆全还田(P)和秸秆不还田(A)处理,采用Biolog Eco技术测定土壤微生物碳源代谢功能,并分析土壤基本理化性质和作物产量。结果显示:深松与秸秆还田均有利于土壤含水量和有机碳含量的提高,0~15 cm土层分别提高了9.78%和24.00%,15~30 cm土层分别提高了7.08%和15.81%;深松提高了15~30 cm土层的pH值6.67%,秸秆还田提高了0~15 cm土层的pH值4.32%。深松和秸秆还田均有利于代谢多样性(丰富度指数、香浓多样性指数)、碳源代谢强度的提高,0~15 cm土层分别提高了26.84%、3.84%和38.02%,15~30 cm土层分别提高了11.87%、 3.63%和14.74%。主成分分析表明常规翻耕秸秆不还田和旋耕耕作秸秆不还田碳源代谢功能相近,15~30 cm层次内常规翻耕秸秆全还田碳源代谢功能和深松耕作秸秆全还田处理相近。深松和秸秆还田平均提高了小麦产量5.82%,微生物碳源代谢功能与小麦产量具有极显著的相关性。 相似文献
4.
Ruimin Chao Chengqiang Xia Caixia Pei Wenjie Huo Qiang Liu Chunxiang Zhang Youshe Ren 《Journal of animal physiology and animal nutrition》2021,105(1):26-34
The objective of this study was to investigate the characteristics of ruminal microbial communities of alpacas (Lama pacos) and sheep (Ovis aries) fed three diets with varying ratios of roughage (corn stalk) to concentrate, 3:7 (LS), 5:5 (MS) and 7:3 (HS). Six alpacas (one-year-old and weighing 29.5 ± 7.1 kg) and six sheep (one-year-old and weighing 27.9 ± 2.7 kg) were used in this study, in a replicated 3 × 3 Latin square experiment. Total protozoa concentration was determined under the microscope; total fungi and methanogens were assessed using quantitative polymerase chain reaction and expressed as a percentage of total bacterial 16S rRNA gene copies; bacterial communities were investigated by targeted 16S rRNA gene (V3–V4 region) sequencing. The percentage of fungi was significantly higher in alpacas than in sheep under the LS diet, while the concentration of protozoa was significantly lower in alpacas under HS, MS and LS diets. The alpha diversity including Shannon, Chao l and ACE indices of bacterial communities was higher in alpacas than in sheep, under the LS diet. A total of 299 genera belonging to 22 phyla were observed in the forestomach of alpaca and sheep, with Bacteroidetes and Firmicutes dominating both animal species. Phyla Armatimonadetes and Fusobacteria, as well as 64 genera, were detected only in alpacas, whereas phyla Acidobacteria and Nitrospira, as well as 44 genera, were found only in sheep. The abundance of cellulolytic bacteria, including Butyrivibrio and Pseudobutyrivibrio, was higher in alpacas than in sheep under all three diets. These differences in the forestomach microbial communities partly explained why alpacas displayed a higher poor-quality roughage digestibility, and a lower methane production. Results also revealed that the adverse effects of high-concentrate diets (70%) were lesser in alpacas than in sheep. 相似文献
5.
Bing Liu Muhamed Jamal Hosen Talukder Eeva Terhonen Maija Lampela Harry Vasander Hui Sun Fred Asiegbu 《Soil Use and Management》2020,36(1):123-138
The microbial community structure and function under forest in tropical peatlands are poorly understood. In this study, we investigated the microbial community structure and diversity in natural peat swamp forest soil, disturbed peat soil and mineral soil in Central Kalimantan, Indonesia, using 454 pyrosequencing. The results showed that the natural peat soil had the greatest fungal species richness (Chao1), which was significantly (p < .05) larger than that in the other two soils. Community structure of both fungi and bacteria in natural peat soil differed significantly from that in the disturbed peat soil (p = .039 and p = .045, respectively). Ascomycota (40.5%) was the most abundant phylum across the three soils followed by Basidiomycota (18.8%), Zygomycota (<0.1%) and Glomeromycota (<0.1%). The linear discriminant analysis with effect size (LEfSe) showed that Ascomycota (p < .05) and genus Gliocephalotrichum (p < .05) dominated in natural peat soil. Functionally, pathotrophs were more abundant in disturbed peat soil (p < .05). Proteobacteria (43.8%) were the most abundant phylum followed by Acidobacteria (32.6%), Actinobacteria (9.8%), Planctomycetes (1.7%). Methylocystis, Telmatospirillum, Syntrophobacter, Sorangium and Opitutus were the more abundant genera in disturbed peat soil, whereas Nevskia and Schlesneria were more abundant in mineral soil and natural peat soil, respectively. The natural peat forest soil supported a more diverse microbiology; however, the land use of such a soil can change its microbial community structure. The results provide evidence that the disturbance of tropical peat land could lead to the introduction and spread of a large number of fungal diseases 相似文献
6.
LIU Weichao FU Shuyue YAN Shengji REN Chengjie WU Shaojun DENG Jian LI Boyong HAN Xinhui YANG Gaihe 《干旱区科学》2020,12(2):215-226
Succession is one of the central themes of ecology;however,the relationship between aboveground plant communities and underground soils during secondary succession remains unclear.In this study,we investigated the composition of plant community,plant-soil C:N:P stoichiometry and their relationships during secondary succession after the abandonment of farmlands for 0,10,20,30,40 and 50 a in China,2016.Results showed that the composition of plant communities was most diverse in the farmlands after secondary succession for 20 and 50 a.Soil organic carbon and total nitrogen contents slightly decreased after secondary succession for 30 a,but both were significantly higher than those of control farmland(31.21%-139.10%and 24.24%-121.21%,respectively).Moreover,C:N ratios of soil and microbe greatly contributed to the changes in plant community composition during secondary succession of abandoned farmlands,explaining 35.70%of the total variation.Particularly,soil C:N ratio was significantly and positively related with the Shannon-Wiener index.This study provides the evidence of synchronous evolution between plant community and soil during secondary succession and C:N ratio is an important linkage between them. 相似文献
7.
Effect of transferring lignocellulose-degrading bacteria from termite to rumen fluid of sheep on in vitro gas production,fermentation parameters,microbial populations and enzyme activity 下载免费PDF全文
Ayoub AZIZI Afrooz SHARIFI Hasan FAZAELI Arash AZARFAR Arjan JONKER Ali KIANI 《农业科学学报》2020,19(5):1323-1331
The digestive tract of termite(Microcerotermes diversus) contains a variety of lignocellulose-degrading bacteria with exocellulases enzyme activity, not found in the rumen, which could potentially improve fiber degradation in the rumen. The objectives of the current study were to determine the effect of inoculation of rumen fluid(RF) with three species of bacteria isolated from termite digestive tract, Bacillus licheniformis, Ochrobactrum intermedium, and Microbacterium paludicola, on in vitro gas production(IVGP), fermentation parameters, nutrient disappearance, microbial populations, and hydrolytic enzyme activities with fibrous wheat straw(WS) and date leaf(DL) as incubation substrate. Inoculation of RF with either of three termite bacteria increased(P0.05) ammonia-N concentration compared with the control group(free of termite gut bacteria). Termite bacteria inoculation had no effect(P0.05) on gas production characteristics, dry matter, organic matter and neutral detergent fiber disappearance, pH, and concentration and composition of volatile fatty acids. Population of proteolytic bacteria and protozoa, but not cellulolytic bacteria, were increased(P0.05) when RF was inoculated with termite bacteria with both WS and DL substrates. Inoculation of RF with termite bacteria increased protease activity, while activities of carboxymethyl-cellulase, microcrystalline-cellulase, α-amylase and filter paper degrading activity remained unchanged(P0.05). Overall, the results of this study indicated that transferring lignocellulose-degrading bacteria, isolated from digestive tract of termite, to rumen liquid increased protozoa and proteolytic bacteria population and consequently increased protease activity and ammonia-N concentration in vitro, however, no effect on fermentation and fiber degradation parameters were detected. These results suggest that the termite bacteria might be rapidly lysed by the rumen microbes before beneficial effects on the rumen fermentation process could occur. 相似文献
8.
社会林业与五指山的自然保护 总被引:1,自引:0,他引:1
五指山自然保护区是世界上现存地势最高的原始热带雨林之一,是我省目前面积最大的自然保护区,也是海南三大河流的发源地。但由于保护区横跨琼中、通什、保亭三县、市,紧邻保护区还生存着众多贫困的黎、苗族村民。因此,保护区与周边社区的联系是十分紧密的,社区的发展也直接影响到五指山热带天然林的保护。海南省林业局中德海南热带林保护和恢复项目在社会林业与五指山森林的保护上做出了有益的尝试,就在全省来说,也是首次对社会林业与森林保护上进行的探索。五指山地区社会林业的研究,对保护海南热带雨林也有着积极的意义。特对社会林业与五指山的森林保护进行了阐述、分析和设想。 相似文献
9.
工厂化代料栽培花菇技术研究初报 总被引:1,自引:0,他引:1
本文主要研究工厂化代料栽培花菇技术,根据花菇成因及香菇菌丝生长、原基分化、花菇形成三个阶段所要求的生态条件不同,分别按三个阶段设计了培养室、催蕾室、催化室,利用设施人工调控工艺条件,进行菌丝培养、催蕾和催花管理,使花菇产量和质量大大提高,小试获得了80%的花菇率,比室外高棚层架方式提高近1倍。 相似文献
10.