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1.
Survival and movement of Escherichia coli O157:H7 in both soil and vermicompost is of concern with regards to human health. Whilst it is accepted that E. coli O157:H7 can persist for considerable periods in soils, it is not expected to survive thermophilic composting processes. However, the natural behavior of earthworms is increasingly utilized for composting (vermicomposting), and the extent to which earthworms promote the survival and dispersal of the bacterium within such systems is unknown. The faecal material produced by earthworms provides a ready supply of labile organic substrates to surrounding microbes within soil and compost, thus promoting microbial activity. Earthworms can also cause significant movement of organisms through the channels they form. Survival and dispersal of E. coli O157:H7 were monitored in contaminated soil and farmyard manure subjected to earthworm digestion over 21 days. Our findings lead to the conclusion that anecic earthworms such as Lumbricus terrestris may significantly aid vertical movement of E. coli O157 in soil, whereas epigeic earthworms such as Dendrobaena veneta significantly aid lateral movement within compost. Although the presence of earthworms in soil and compost may aid proliferation of E. coli O157 in early stages of contamination, long-term persistence of the pathogen appears to be unaffected.  相似文献   

2.
Delschen  Thomas 《Plant and Soil》1999,213(1-2):43-54
On the basis of long-term field experiments, the impact is demonstrated of the periodic application of organic fertilizers on the accumulation of organic matter and the development of the micro-pollutant content of reclaimed loess soils of the Rhineland lignite mining area under agricultural use. The oldest of these experiments (‘Berrenrath Humus Accumulation Experiment’) was begun in 1969. The results show that the regular input of organic matter (e.g. manure, waste compost, sewage sludge) favors the accumulation of soil organic matter (SOM). However, the type of organic material applied seems to be less important to the long-term accumulation process than the application rate. This is also true for composted and uncomposted manure, if the decay of organic matter during the composting process is taken into account. Nevertheless, the application of similar amounts of organic C in the form of manure resulted in a higher accumulation of SOM in a nitrogen-reduced farming system. Depending on the treatment, accumulation rates were between 0.02 and 0.08% SOM per year with values decreasing with time. From these results, it is estimated that reclaimed soils will take much longer to reach the former SOM level than was previously assumed. However, it is important to determine which SOM level is adequate for different soil functions (e.g. production function, filter and buffer function, transformation function), and whether the young SOM of reclaimed soils has the same properties as older SOM in undisturbed topsoils. As was expected, long-term fertilization with sewage sludge and waste compost led to an accumulation of some micro-pollutants in the topsoils treated. Nevertheless, the observed concentrations are quite low compared to background levels in topsoils of rural regions in North Rhine-Westphalia. This revised version was published online in June 2006 with corrections to the Cover Date. This revised version was published online in June 2006 with corrections to the Cover Date. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

3.
Chemical immobilization using animal manure compost is one of the most useful for low-cost, in-situ soil remediation techniques. The present study aimed to determine suitable chemical properties of animal manure compost to facilitate lead (Pb) immobilization in soil. The level of mobile Pb in soil amended with swine compost was higher than that amended with cattle compost during the early stage of incubation. However, the level of mobile Pb was almost the same in soil amended with both types of compost on day 184 of incubation. The ratio of the residual fraction after sequential extraction was enhanced in soil amended with both types of compost, particularly swine compost. X-ray diffractometer (XRD) results demonstrated the precipitation of Pb phosphate minerals, such as pyromorphite, in Pb-sorbed composts, particularly swine compost. Amendment using swine compost could reduce Pb solubility even when it had a high content of water-soluble organic matter because it significantly lowered Pb phase solubility. The amendment with swine compost improved plant growth and microbial activity. This study suggests that composts with high phosphorus (P) content are suitable for Pb immobilization amendment even if they have a high water-soluble organic matter content.  相似文献   

4.
The utilization of agricultural waste organic materials through composting technology has gained significant traction in agricultural production as an effective means of crop nutrient management. However, the differences in the impact of organic amendments prepared by traditional composting and vermicomposting on soil properties still deserve further research. Based on field experiments conducted in greenhouse, compared to chemical fertilizer treatments as control, we utilized traditional compost (OF) and vermicompost (VcF) derived from agricultural organic waste edible mushroom bran and cow manure (2:8). Variations in soil physiochemical properties, activities of soil enzymes related C and P cycling, abundances and diversities of bacterial 16S rRNA and fungal ITS gene at total DNA level were analyzed. Both compost treatments enhanced soil organic carbon, soil total phosphorus, and soil available P content significantly and also increased the activities of soil α-glucosidase, β-glucosidase, acid phosphomonoesterase, and alkaline phosphomonoesterase significantly. The above results suggested that soil C and P transformations were stimulated effectively by both organic amendments. OF and VcF increased the fungal ITS absolute abundances significantly while diversity indices of soil bacterial community increased significantly under both treatments. Correlation analysis indicated that bacterial community composition was strongly correlated with several soil property indexes while fungal community composition was only significantly correlated with soil total phosphorous content. In conclusion, similar to traditional compost, vermicompost significantly improved soil nutrient cycling (especially C and P aspects). In terms of soil microbes, bacteria and fungi showed different responding mechanism to vermicompost: bacteria adjust microbial structure, while fungi tend to proliferated. In consideration of the advantages of vermicompost in technology and economic cost, it could be applied in the subsequent agricultural production more frequently.  相似文献   

5.
The effects of usual or recommended rates of application of five organic amendments (24 t/ha yr of MSW compost, sewage sludge, and ovine manure, 2.4 t/ha yr of commercial vermicompost, and 100 l/ha yr of a commercial humic acids solution) on the soil contents of organic matter, total humified substances, humic acids, carbohydrates and microbial gums, and the structural stability of aggregates were investigated. Four and five years after the beginning of the experiment, significant increments in most of the parameters studied were found after the application of organic residues, whereas the two commercial amendments did not produce any significant change, suggesting that rates recommended by the producers and imposed by their high prices are too low to be useful. MSW compost yielded the highest increases, even if the amount of organic matter applied as ovine manure was very similar. Organic matter and carbohydrates appeared to be the parameters most closely related to soil aggregate stability.  相似文献   

6.
Organic amendments, such as compost and biochar, mitigate the environmental burdens associated with wasting organic resources and close nutrient loops by capturing, transforming, and resupplying nutrients to soils. While compost or biochar application to soil can enhance an agroecosystem's capacity to store carbon and produce food, there have been few field studies investigating the agroecological impacts of amending soil with biochar co-compost, produced through the composting of nitrogen-rich organic material, such as manure, with carbon-rich biochar. Here, we examine the impact of biochar co-compost on soil properties and processes by conducting a field study in which we compare the environmental and agronomic impacts associated with the amendment of either dairy manure co-composted with biochar, dairy manure compost, or biochar to soils in a winter wheat cropping system. Organic amendments were applied at equivalent C rates (8 Mg C ha−1). We found that all three treatments significantly increased soil water holding capacity and total plant biomass relative to the no-amendment control. Soils amended with biochar or biochar co-compost resulted in significantly less greenhouse gas emissions than the compost or control soils. Biochar co-compost also resulted in a significant reduction in nutrient leaching relative to the application of biochar alone or compost alone. Our results suggest that biochar co-composting could optimize organic resource recycling for climate change mitigation and agricultural productivity while minimizing nutrient losses from agroecosystems.  相似文献   

7.
Two laboratory-scale systems were set up (i) composting (without earthworms) and (ii) vermicomposting (with earthworms) and were monitored for 60 days after pre-composting. The physico-chemical parameters (pH, C/N, organic matter, NH(4)(+)-N and ash content) showed similar evolution in both systems except a higher NH(4)(+)-N in the initial vermicomposts. However, principle component analysis (PCA) of enzymatic activities and community level physiological profiles revealed differences in the functional response of microbial communities in compost and vermicompost during maturation. Dehydrogenase activity and bacterial counts indicated a steady decrease in biological activity and population during composting, whereas vermicomposting exhibited higher activity on day 30 and a reduction in bacterial counts on day 10. PCA of denatured gradient gel electrophoresis (DGGE) profiles showed divergent dynamics of bacterial communities in two processes. These results indicated differences in the functional response and genetic structure of microbial community in composts and vermicomposts despite similar changes in their physico-chemical parameters.  相似文献   

8.
Blanco  M.-J.  Almendros  G. 《Plant and Soil》1997,196(1):15-25
Chemical maturity parameters in addition to plant growth limiting factors have been monitored in the course of a 2-month composting experiment. Wheat straw with 5% dry w horse manure was adjusted to C/N= 45 with urea. The pile was rotated and homogeneous samples were taken every four days. The most intense changes in straw fractions occurred in the first 20 days of composting, as suggested by wet chemical analyses, thermogravimetry and 13C NMR spectrometry. Nevertheless, plant response to compost application gave significant changes at between 20–60 days that were not clearly reflected by the above techniques. Glasshouse experiments with a soil treated with compost samples taken at the successive transformation stages suggested no linear correlation between composting time and the potential of compost in improving plant yield. In the samples taken after 20 days in the conditions studied, referred to as postmature composts, the ryegrass yield did not depend on most of the organic matter characteristics, but closely paralleled the concentration of available nitrogen and – to lesser extent – phosphorous in the compost. The probable immobilization of these elements in the course of composting was also suggested by plant response experiments with different doses of compost and the addition or not of mineral solution.  相似文献   

9.
Aira M  Domínguez J 《PloS one》2011,6(1):e16354

Background

Earthworms are key organisms in organic matter decomposition because of the interactions they establish with soil microorganisms. They enhance decomposition rates through the joint action of direct effects (i.e. effects due to direct earthworm activity such as digestion, burrowing, etc) and indirect effects (i.e. effects derived from earthworm activities such as cast ageing). Here we test whether indirect earthworm effects affect microbial community functioning in the substrate, as when earthworms are present (i. e., direct effects).

Methodology/Principal Findings

To address these questions we inoculated fresh organic matter (pig manure) with worm-worked substrates (vermicompost) produced by three different earthworm species. Two doses of each vermicompost were used (2.5 and 10%). We hypothesized that the presence of worm-worked material in the fresh organic matter will result in an inoculum of different microorganisms and nutrients. This inoculum should interact with microbial communities in fresh organic matter, thus promoting modifications similar to those found when earthworms are present. Inoculation of worm-worked substrates provoked significant increases in microbial biomass and enzyme activities (β-glucosidase, cellulase, phosphatase and protease). These indirect effects were similar to, although lower than, those obtained in pig manure with earthworms (direct and indirect earthworm effects). In general, the effects were not dose-dependent, suggesting the existence of a threshold at which they were triggered.

Conclusion/Significance

Our data reveal that the relationships between earthworms and microorganisms are far from being understood, and suggest the existence of several positive feedbacks during earthworm activity as a result of the interactions between direct and indirect effects, since their combination produces stronger modifications to microbial biomass and enzyme activity.  相似文献   

10.
The aim of this study was to evaluate chemical and biochemical changes of organic matter in fertilized (ammonium nitrate) and amended (vermicompost and manure) soils using pyrolysis and metabolic indices. The metabolic potential [dehydrogenase (DH-ase)/water soluble organic carbon (WSOC)], the metabolic quotient (qCO2) and the microbial quotient (Cmic:Corg) were calculated as indices of soil organic matter evolution. Pyrolysis-gas chromatography (Py-GC) was used to study structural changes in the organic matter. Carbon forms and microbial biomass have been measured by dichromate oxidation and fumigation-extraction methods, respectively. Dehydrogenase activity has been tested using INT (p-Iodonitrotetrazolium violet) as substrate. The results showed that organic amendment increased soil microbial biomass and its activity which were strictly related to pyrolytic mineralization and humification indices (N/O, B/E3). Mineral fertilization caused a greater alteration of native soil organic matter than the organic amendments, in that a high release of WSOC and relatively large amounts of aliphatic pyrolytic products, were observed. Therefore, the pyrolysis and metabolic indices provided similar and complementary information on soil organic matter changes after mineral and organic fertilization.  相似文献   

11.
有机物料种类及腐熟水平对土壤微生物群落的影响   总被引:24,自引:2,他引:22  
应用Biolog方法研究了温室盆栽番茄条件下,施用不同种类及不同腐熟水平的有机物料对土壤微生物群落的影响,施用有机物料60d后取土分析土壤微生物群落多样性及土壤微生物对Biolog微平板中胺、氨基酸、糖、羧酸、聚合物和其它类碳源的利用情况,结果表明,施用有机物料可提高土壤微生物群落多样性,施用新鲜酒糟的多样性指数略高于施用腐熟10d酒糟,牛粪不同腐熟水平对多样性影响显著,且对多样性具有正向或负向的影响;对照和施用酒糟的土壤微生物对聚合物的利用率高于施用牛粪处理,施用新鲜物料处理的土壤微生物对聚合物的利用率高于施用腐熟物料处理。  相似文献   

12.
The utility of an urban solid waste, either freshly composted or vermicomposted, for improvement of plant growth in a soil B horizon was investigated. Growth, mineral nutrition and arbuscular mycorrhizal (AM) colonization of cucumber and red clover plants were studied in an experiment carried out under controlled growing conditions, using different mixtures of soil and composts as plant substrates. Soil inoculation with the AM fungus Acaulospora sp. did not benefit growth of plants when soil was used as the only substrate, possibly due to its poor fertility. Results showed that neither mycorrhizal plant species grew when soil was mixed with composted urban waste or when compost was used as the only substrate. However, amendment of soil with 10 or 50% vermicompost significantly increased dry matter yields of red clover and cucumber plants, compared to treatments where soil was the only substrate. Addition of vermicompost also increased Olsen-P and other mineral elements in soil and shoot P, Ca, Mg, Cu, Mn and Zn concentrations, but caused a significant reduction on root length colonized by AM fungi in red clover plants. It is concluded that application of high amounts of vermicompost from composted urban wastes to soils might cause a significant reduction of activity of AM fungi, which must be taken into account when using these organic amendments in agricultural systems.  相似文献   

13.
Compost production is a critical component of organic waste handling, and compost applications to soil are increasingly important to crop production. However, we know surprisingly little about the microbial communities involved in the composting process and the factors shaping compost microbial dynamics. Here, we used high-throughput sequencing approaches to assess the diversity and composition of both bacterial and fungal communities in compost produced at a commercial-scale. Bacterial and fungal communities responded to both compost recipe and composting method. Specifically, bacterial communities in manure and hay recipes contained greater relative abundances of Firmicutes than hardwood recipes with hay recipes containing relatively more Actinobacteria and Gemmatimonadetes. In contrast, hardwood recipes contained a large relative abundance of Acidobacteria and Chloroflexi. Fungal communities of compost from a mixture of dairy manure and silage-based bedding were distinguished by a greater relative abundance of Pezizomycetes and Microascales. Hay recipes uniquely contained abundant Epicoccum, Thermomyces, Eurotium, Arthrobotrys, and Myriococcum. Hardwood recipes contained relatively abundant Sordariomycetes. Holding recipe constant, there were significantly different bacterial and fungal communities when the composting process was managed by windrow, aerated static pile, or vermicompost. Temporal dynamics of the composting process followed known patterns of degradative succession in herbivore manure. The initial community was dominated by Phycomycetes, followed by Ascomycota and finally Basidiomycota. Zygomycota were associated more with manure-silage and hay than hardwood composts. Most commercial composters focus on the thermophilic phase as an economic means to insure sanitation of compost from pathogens. However, the community succeeding the thermophilic phase begs further investigation to determine how the microbial dynamics observed here can be best managed to generate compost with the desired properties.  相似文献   

14.
Application of organic fertilizers and charcoal increase nutrient stocks in the rooting zone of crops, reduce nutrient leaching and thus improve crop production on acid and highly weathered tropical soils. In a field trial near Manaus (Brazil) 15 different amendment combinations based on equal amounts of carbon (C) applied through chicken manure (CM), compost, charcoal, and forest litter were tested during four cropping cycles with rice (Oryza sativa L.) and sorghum (Sorghum bicolor L.) in five replicates. CM amendments resulted in the highest (P < 0.05) cumulative crop yield (12.4 Mg ha−1) over four seasons. Most importantly, surface soil pH, phosphorus (P), calcium (Ca), and magnesium (Mg) were significantly enhanced by CM. A single compost application produced fourfold more grain yield (P < 0.05) than plots mineral fertilized in split applications. Charcoal significantly improved plant growth and doubled grain production if fertilized with NPK in comparison to the NPK-fertilizer without charcoal (P < 0.05). The higher yields caused a significantly greater nutrient export in charcoal-amended fields, but available nutrients did not decrease to the same extent as on just mineral fertilized plots. Exchangeable soil aluminum (Al) was further reduced if mineral fertilizer was applied with charcoal (from 4.7 to 0 mg kg−1). The resilience of soil organic matter (SOM) in charcoal amended plots (8 and 4% soil C loss, mineral fertilized or not fertilized, respectively) indicates the refractory nature of charcoal in comparison to SOM losses over 20 months in CM (27%), compost amended (27%), and control plots (25% loss).  相似文献   

15.
采用连续提取法研究了猪粪好氧堆肥处理中重金属浓度和形态的变化以及添加不同比例的重金属钝化剂对其浓度和形态的影响.结果表明:经过堆肥处理后,猪粪中重金属As、Cu和Zn的总浓度均有所增加.从重金属结合形态的变化来看,可交换态As和Zn含量降低,残渣态As和Zn含量升高,表明As和Zn存在着向有效性相对较低的形态转化的趋势;重金属Cu则表现出不同的变化趋势,即可交换态与残渣态Cu含量下降,而碳酸盐结合态、铁锰结合态及有机结合态Cu含量有所增加,在今后的堆肥利用中应注意其可能带来的环境风险;3种重金属钝化剂及不同添加比例的处理中,5.0%的海泡石和2.5%的膨润土分别对重金属As、Zn表现出较好的钝化效果,堆肥后残渣态As和Zn的增幅分别达到79.8%和158.6%,均高于不加钝化剂处理.与对照相比,堆肥后7.5%的海泡石对残渣态Cu的降低幅度最小,为39.3%.猪粪堆肥中添加适量的重金属钝化剂,可以在一定程度上降低重金属的有效性以及猪粪堆肥利用中重金属污染的风险.  相似文献   

16.
The way of improving degraded soils fertility and particularly of improving its microbial activity is to add “young” exogenous organic matter that contribute to provide labile organic matter to stimulate the life of the microorganisms existing in the soil. This organic matter will also improve both the retention and hydraulic characteristics of the degraded soils, all this contributing to soil restoration. In this study, the microbiological, biochemical, soil-physical and hydrological effects of the addition of a municipal solid waste compost to a degraded soil in El Campello, SE Spain were evaluated in a field experiment. Soil samples from experimental plots were analyzed 6 and 18 months after soil amendment. In both sampling time treated plots showed significantly higher microbial biomass carbon and dehydrogenase activity values than control, indicating that soil microbial population’s development and activity were stimulated by compost addition, this effect being not ephemeral but lasting in the time. Soil urease activity was not affected by compost addition while protease hydrolysing N-α-benzoil-L-argininamide (BAA) activity was strongly stimulated by the incorporation of compost into the soils. Phosphatase and β-glucosidase activities were also stimulated by the organic amendment, this stimulation being particularly noticeable 18 months after the compost addition. Nevertheless, this increase in soil microbial populations and activity did not result in an increase in soil aggregation and hydrological parameters. This can be due to the high content of carbonates and Ca2+ ions in these calcareous soils, that lead to an initially high content of water-stable macroaggregates. Presented at the International Conference on Bioclimatology and Natural Hazards, Poľana nad Detvou, Slovakia, 17–20 September 2007.  相似文献   

17.
Compost amendment has been reported to impact soil microbial activities or community composition. However, little information is available on (i) to what extent compost amendment concurrently affects the activity, size and composition of soil microbial community, (ii) the relative effect of the addition of a material rich in organic matter versus addition of compost-borne microorganisms in explaining the effects of amendment and (iii) the resilience of community characteristics. We compared five treatments in microcosms: (i) control soil (S), (ii) soil + low level of compost (Sc), (iii) soil + high level of compost (SC), (iv) sterilized soil + high level of compost [(S)C] and (v) soil + high level of sterilized compost [S(C)]. The actual C mineralization rate, substrate-induced respiration, size of microbial community (biomass and heterotrophic cells number), and structure of total microbial (phospholipid fatty acids) and bacterial (automated ribosomal intergenic spacer analysis, A-RISA) communities were surveyed during 6 months after amendment. Our results show that (i) compost amendment affected the activity, size and composition of the soil microbial community, (ii) the effect of compost amendment was mainly due to the physicochemical characteristics of compost matrix rather than to compost-borne microorganisms and (iii) no resilience of microbial characteristics was observed 6-12 months after amendment with a high amount of compost.  相似文献   

18.
Mispah form (FAO: Lithosol) soil contaminated with >380 000 mg kg?1 creosote was co-composted with cattle manure and mixed vegetable waste for 19 months. The soil was mixed with wood chips to improve aeration and then mixed with cattle manure or mixed vegetable waste in a ratio of 4:1. Moisture, temperature, pH, ash content, C:N ratios, and the concentrations of creosote in the compost systems were monitored monthly. The concentrations of selected hydrocarbons in the compost systems were determined at the end of composting. Temperature rose to about 45°C in the cattle manure compost within two months of incubation while temperature in the control and vegetable waste remained below 30°C until the fourth month. Creosote concentration was reduced by 17% in the control and by more than 99% in the cattle manure and vegetable waste compost after composting. The rate of reduction in concentration in the mixed vegetable waste compost was initially lower than in the cattle manure compost. The reduction rate became similar in later months with only small differences towards the end of the composting. The concentrations of selected creosote components were reduced by between 96% and 100% after composting. There was no significant difference in reduction in concentration in both compost systems at p 0.05. Microbial activity correlated with reduction in creosote concentration.  相似文献   

19.
The aim of this study was to couple biochemical and molecular methodologies for evaluating the impact of two recycling technologies (composting and vermicomposting) on a toxic organic waste. To do this, six enzyme activities controlling the key metabolic pathways of the breakdown of organic matter, real-time PCR assays targeting 16S rRNA genes, and denaturing gradient gel electrophoresis (DGGE) profiling-sequence analysis of PCR-amplified 16S rRNA fragments have been used to determine the functional diversity, bacterial number, and bacterial community structure, respectively, in a mixture of olive waste and sheep manure, and in the derived compost and vermicompost. Both the recycling technologies were effective in activating the microbial parameters of the toxic waste, the vermicomposting being the best process to produce greater bacterial diversity, greater bacterial numbers and greater functional diversity. Although several identical populations were detected in the processed and non-processed materials, each technology modified the original microbial communities of the waste in a diverse way, indicating the different roles of each one in the bacterial selection.  相似文献   

20.
Chertov  O. G.  Komarov  A. S.  Tsiplianovsky  A. M. 《Plant and Soil》1999,213(1-2):31-41
The individual-based combined forest model EFIMOD including the soil-sub model SOMM has been used for the simulation of Scots pine stand growth and soil organic matter (SOM) accumulation on a humus-free bare mineral surface. The growth of Scots pine plantation, with an initial density of 10 000 trees ha−1 and average tree biomass of 0.01 kg was simulated for 50 yr under Central European climatic conditions (i) with varying atmospheric nitrogen inputs and (ii) different rates of initial application of raw undecomposed organic material or compost, on humus-free parent material. The accumulation of typical raw humus was simulated in all cases. The accumulation was most intensive in the simulation of high atmospheric nitrogen input. The humus pool in the mineral topsoil was small but achieved its maximum value with compost application. SOM nitrogen accumulation was scant in all cases, except the compost applications with low atmospheric nitrogen input. No statistically significant differences of SOM and stand parameters were found between variants without organic matter and those with low input of organic manure. However, the maximum relative rate of SOM and nitrogen accumulation was found in the scenario without organic manure, under slowly growing unstable Scots pine plantation. This revised version was published online in June 2006 with corrections to the Cover Date. This revised version was published online in June 2006 with corrections to the Cover Date. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

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