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1.
A new isolate of Trichoderma atroviride has been shown to grow on low rank coal as the sole carbon source. T. atroviride ES11 degrades ∼82% of particulate coal (10 g l−1) over a period of 21 days with 50% reduction in 6 days. Glucose (5 g l−1) as a supplemented carbon source enhanced the coal solubilisation efficiency of T. atroviride ES11, while 10 and 20 g l−1 glucose decrease coal solubilisation efficiency. Addition of nitrogen [1 g l−1 (NH4)2SO4] to the medium also increased the coal solubilisation efficiency of T. atroviride ES11. Assay results from coal-free and coal-supplemented cultures suggested that several intracellular enzymes are possibly involved in coal depolymerisation processes some of which are constitutive (phenol hydroxylase) and others that were activated or induced in the presence of coal (2,3-dihydrobiphenyl-2,3-diol dehydrogenase, 3,4-dihydro phenanthrene-3,4-diol dehydrogenase, 1,2-dihydro-1,2-dihydroxynaphthalene dehydrogenase, 1,2-dihydro-1,2-dihydroxyanthracene dehydrogenase). GC-MS analysis of chloroform extracts obtained from coal degrading T. atroviride ES11 cultures showed the formation of only a limited number of specific compounds (4-hydroxyphenylethanol, 1,2-benzenediol, 2-octenoic acid), strongly suggesting that the intimate association between coal particles and fungal mycelia results in rapid and near-quantitative transfer of coal depolymerisation products into the cell. An erratum to this article can be found at  相似文献   

2.
Summary The adsorption of Sulfolobus acidocaldarius on bituminous coal surfaces and the respiration rate during adsorption at 70° C were enhanced at pH 1.0–2.0, in comparison with those at pH 3.0–5.0. The maximum number of bacterial cells adsorbed per unit area of coal attained a maximum (1.4 × 1011 cells/m2) at pH 2.0. The rate of desulphurization at pH 2.2–2.5 was higher than at other pHs tested. Micrographs of S. acidocaldarius obtained by TEM and SEM indicated that the cells were adsorbed to the coal surfaces by extracellular slime. Specific inhibitors of membrane-bound ATPase (NaF, 20 mm) and respiration (NaN3, 1 mm; KCN, 1 mm) had pronounced effects on suppressing adsorption. The amount of S. acidocaldarius adsorbed decreased when the coal particles were leached in advance with 2.0 m HNO3. These facts lead to the conclusion that the adsorption of S. acidocaldarius on coal surfaces requires physiological activity relatd to respiration or energy conversion. Offprint requests to: V. B. Vitaya  相似文献   

3.
Coal mining is responsible for 11% of total anthropogenic methane emission thereby contributing considerably to climate change. Attempts to harvest coalbed methane for energy production are challenged by relatively low methane concentrations. In this study, we investigated whether nutrient and acetate amendment of a non‐producing sub‐bituminous coal well could transform the system to a methane source. We tracked cell counts, methane production, acetate concentration and geochemical parameters for 25 months in one amended and one unamended coal well in Australia. Additionally, the microbial community was analysed with 16S rRNA gene amplicon sequencing at 17 and 25 months after amendment and complemented by metagenome sequencing at 25 months. We found that cell numbers increased rapidly from 3.0 × 104 cells ml?1 to 9.9 × 107 in the first 7 months after amendment. However, acetate depletion with concomitant methane production started only after 12–19 months. The microbial community was dominated by complex organic compound degraders (Anaerolineaceae, Rhodocyclaceae and Geobacter spp.), acetoclastic methanogens (Methanothrix spp.) and fungi (Agaricomycetes). Even though the microbial community had the functional potential to convert coal to methane, we observed no indication that coal was actually converted within the time frame of the study. Our results suggest that even though nutrient and acetate amendment stimulated relevant microbial species, it is not a sustainable way to transform non‐producing coal wells into bioenergy factories.  相似文献   

4.
Green algal communities were investigated in clean and pollution-impacted tundra soils around the large coal mine industrial complex of Vorkuta in the E. European Russian tundra. Samples were collected in three zones of open-cast coal mining with different degrees of pollution-impacted soil transformation. A total of 42 species of algae were found in all zones. The species richness decreased from 27 species in undisturbed zones to 19 species in polluted zones. Under open-cast coal mining impacts the community structure simplified, and the dominant algae complexes changed. Algae that are typical for clean soils disappeared from the communities. The total abundance of green algae (counted together with Xanthophyta) ranged between 100–120 × 103 (cells/g dry soils) in undisturbed zones and 0.5–50 × 103 in polluted zones. Soil algae appear to be better indicators of coal mine technogenic pollution than flowering plants and mosses. Presented at the International Symposium Biology and Taxonomy of Green Algae V, Smolenice, June 26–29, 2007, Slovakia.  相似文献   

5.
Willow Salix sp. is currently cultivated as a short rotation forestry crop in Ireland as a source of biomass to contribute to renewable energy goals. The aim of this study is to evaluate the energy requirements and environmental impacts associated with willow (Salix sp.) cultivation, harvest, and transport using life cycle assessment (LCA). In this study, only emissions from the production of the willow chip are included, end‐use emissions from combustion are not considered. In this LCA study, three impact categories are considered; acidification potential, eutrophication potential and global warming potential. In addition, the cumulative energy demand and energy ratio of the system are evaluated. The results identify three key processes in the production chain which contribute most to all impact categories considered; maintenance, harvest and transportation of the crop. Sensitivity analysis on the type of fertilizers used, harvesting technologies and transport distances highlights the effects of these management techniques on overall system performance. Replacement of synthetic fertilizer with biosolids results in a reduction in overall energy demand, but raises acidification potential, eutrophication potential and global warming potential. Rod harvesting compares unfavourably in comparison with direct chip harvesting in each of the impact categories considered due to the additional chipping step required. The results show that dedicated truck transport is preferable to tractor‐trailer transport in terms of energy demand and environmental impacts. Finally, willow chip production compares favourably with coal provision in terms of energy ratio and global warming potential, while achieving a higher energy ratio than peat provision but also a higher global warming potential.  相似文献   

6.
露天煤矿煤粉沉降对矿区周边主要植物的生理影响   总被引:1,自引:0,他引:1  
李玉洁  赵娜  曹月娥  杨建军 《生态学报》2018,38(22):8129-8138
随着新疆准东煤田开采的日益加剧,露天开采及运输造成的煤粉尘不仅影响区域大气环境,同时在一定程度上影响周边植物的生理生长。为探讨煤粉尘对周边植物的生理影响,以准东露天煤矿周边人工绿化树种白榆、乡土植物梭梭和柽柳为研究对象,通过野外控制实验,探究覆尘、无尘条件下3种植物的光合生理特性的变化。结果表明:煤粉沉降对3种植物的光合生理均产生了明显影响,覆尘叶片在不同光照强度下净光合速率、气孔导度、蒸腾速率均降低,净光合速率柽柳(18.6%)梭梭(28.3%)白榆(30.7%),气孔导度梭梭(24.1%)柽柳(30.9%)白榆(33.2%),蒸腾速率梭梭(16.7%)白榆(18%)柽柳(39.1%);煤尘对白榆、梭梭的影响主要为非气孔因素,对柽柳的影响有待继续研究。因此露天煤矿开采造成的粉尘会在一定程度上影响周边植物的光合生理过程,抑制其生长,长期排放可能会导致植被覆盖度降低。  相似文献   

7.
Summary Activated sludge was successful in reducing the levels of dissolved organic carbon (DOC) in coal slurry wastewaters. DOC removal by the activated sludge ranged from 61% to 97% with a large percentage (21–41%) of this DOC being completely metabolized to CO2. Second order kinetic constants (k 2) developed for DOC removal ranged from 1.39·10–4 to 2.30·10–1 liter·day–1·(mg of sludge)–1, providing evidence that biological treatment was an effective mechanism for reducing the pollution potential of the slurry wastewaters. After treatment with activated sludge a residual DOC remained in the wastewater and data from ultrafiltration studies indicated that this residual carbon was of MW>1000. The activated sludge preferentially removed the lower (MW<1000) molecular weight compounds and the higher molecular weight DOC was more resistant to biological attack. However, extended acclimation (greater than 1 month) enabled the activated sludge to remove the higher molecular weight DOC from the slurry wastewaters.  相似文献   

8.
刘秀丽  郭丕斌  王昕 《生态学报》2020,40(24):8999-9010
我国煤炭资源型地区众多,但其资源环境等可持续发展问题形势严峻,如何针对能源和水这两种重点资源进行协同管理是解决这些问题的关键之一。基于区域不同产业能-水耦合视角,采用投入产出分析对2002-2012年山西省不同产业的能-水足迹效率进行评价,并采用结构分解分析能-水耦合的影响因素,主要结论有:(1)研究期间,山西省各产业能-水足迹都呈上升趋势,能源足迹的增加主要表现为各产业间接消耗能源的增加,而水足迹的增加主要表现为各产业直接消耗水资源的增加。(2)不同行业能-水足迹效率差异很大,足迹较大的产业其足迹效率都较低。尽管研究期间各产业能-水足迹效率呈现上升趋势,但大部分产业能-水足迹效率仍处于较低水平。(3)从各产业能源足迹效率和水足迹效率的耦合情况来看,各产业能-水足迹效率耦合状况趋于优化,逐步由低水足迹效率和中等能源足迹效率(WlEm)为主转变为中等水足迹效率和中等能源足迹效率(WmEm)为主,但与发达地区相比,仍然具有一定的差距。(4)从能-水足迹效率影响因素来看,各产业技术水平的提高是导致能-水足迹效率提高的主要动力,经济规模的持续扩大是各产业能-水足迹上升的主要原因,部门间的联系和地区经济结构对能-水足迹效率的影响也逐步增加。这些发现从理论上揭示了资源利用强度和效率对产业能-水消耗的影响机制,从实践上对资源型地区节能节水具有重要指导意义。  相似文献   

9.
Fundamental processes involved in the microbial degradation of coal and its derivatives have been well documented. A mutualistic interaction between plant roots and certain microorganisms to aid growth of plants such as Cynodon dactylon (Bermuda grass) on hard coal dumps has recently been suggested. In the present study coal bioconversion activity of nonmycorrhizal fungi was investigated in the C. dactylon/coal rhizosphere. Fungal growth on 2% Duff-agar, gutation formation on nitric acid treated coal and submerged culture activity in nitrogen-rich and -deficient broth formed part of the screening and selection of the fungi. The selected fungal isolates were confirmed to be found in pristine C. dactylon/coal rhizosphere. To simulate bioconversion, a fungal aliquot of this rhizosphere was used as inoculum for a Perfusate fixed bed bioreactor, packed with coal. The results demonstrate an enhanced coal bioconversion facilitated by low molecular weight organics and the bioconversion of coal may be initiated by an introduction of nitrogen moieties to the coal substrate. These findings suggest a phyto-bioconversion of hard coal involving plant and microbes occurring in the rhizosphere to promote the growth of C. dactylon. An understanding of this relationship can serve as a benchmark for coal dumps rehabilitation as well as for the industrial scale bioprocessing of hard coal.  相似文献   

10.
We investigated microbial methanogenesis and community structure based on 16S rRNA gene sequences from a coal seam aquifer located 843–907 m below ground level in northern Japan; additionally, we studied the δ13C and δ2H (δD) of coal‐bed gases and other physicochemical parameters. Although isotopic analysis suggested a thermocatalytic origin for the gases, the microbial activity and community structure strongly implied the existence of methanogenic microbial communities in situ. Methane was generated in the enrichment cultures of the hydrogenotrophic and methylotrophic microorganisms obtained from coal seam groundwater. Methanogen clones dominated the archaeal 16S rRNA gene libraries and were mostly related to the hydrogenotrophic genus Methanoculleus and the methylotrophic genus Methanolobus. Bacterial 16S rRNA gene libraries were dominated by the clones related to the genera Acetobacterium and Syntrophus which have a symbiotic association with methanogens. LIBSHUFF analysis revealed that N2 gas injected into the coal seam (for enhanced methane production) does not affect the coverage of archaeal and bacterial populations. However, amova analysis does provide evidence for a change in the genetic diversity of archaeal populations that are dominated by methanogens. Therefore, N2 injection into the coal seam might affect the cycling of matter by methanogens in situ.  相似文献   

11.
Toxicity of the effluent generated at the Rajrappa coal mine complex under the Central Coalfields Limited (CCL, a subsidiary of Coal India Limited) in Jharkhand, India was investigated. The concentrations (mg L?1) of all the toxic metals (Fe, Mn, Ni, Zn, Cu, Pb, Cr, and Cd) in the coal mine effluent were above the safe limit suggested by the Environmental Protection Agency (EPA 2003). Among these, Fe showed the highest concentration (18.21 ± 3.865), while Cr had the lowest effluent concentration (0.15 ± 0.014). Efforts were also made to detoxify the effluent using two species of aquatic macrophytes namely “‘Salvinia molesta and Pistia stratiotes.” After 10 days of phytoremediation, S. molesta removed Pb (96.96%) > Ni (97.01%) > Cu (96.77%) > Zn (96.38%) > Mn (96.22%) > Fe (94.12%) > Cr (92.85%) > Cd (80.99%), and P. stratiotes removed Pb (96.21%) > Fe (94.34%) > Ni (92.53%) > Mn (85.24%) > Zn (79.51%) > Cr (78.57%) > Cu (74.19%) > Cd (72.72%). The impact of coal mine exposure on chlorophyll content showed a significant decrease of 42.49% and 24.54% from control values in S. molesta and P. stratiotes, respectively, perhaps due to the damage inflicted by the toxic metals, leading to the decay of plant tissues.  相似文献   

12.
Trypanosoma cruzi is the etiological agent of Chagas disease. During its life cycle, it alternates among vertebrate and invertebrate hosts. Metabolic flexibility is a main biochemical characteristic of this parasite, which is able to obtain energy by oxidizing a variety of nutrients that can be transported from the extracellular medium. Moreover, several of these metabolites, more specifically amino acids, have a variety of functions beyond being sources of energy. Branched chain amino acids (BCAA), beyond their role in ATP production, are involved in sterol biosynthesis; for example, leucine is involved as a negative regulator of the parasite differentiation process occurring in the insect midgut. BCAA are essential metabolites in most nonphotosynthetic eukaryotes, including trypanosomes. In view of this, the metabolism of BCAA in T. cruzi depends mainly on their transport into the cell. In this work, we kinetically characterized the BCAA transport in T. cruzi epimastigotes. Our data point to BCAA as being transported by a single saturable transport system able to recognize leucine, isoleucine and valine. In view of this, we used leucine to further characterize this system. The transport increased linearly with temperature from 10 to 45 °C, allowing the calculation of an activation energy of 51.30 kJ/mol. Leucine uptake was an active process depending on ATP production and a H+ gradient, but not on a Na+ or K+ gradient at the cytoplasmic membrane level.  相似文献   

13.
鹤岗矿区生态系统服务价值   总被引:5,自引:2,他引:3  
龙精华  张卫  付艳华  胡振琪 《生态学报》2021,41(5):1728-1737
生态系统服务与人类福祉有着密切的关系。采用修正后的单位面积生态系统价值当量因子的方法,对鹤岗矿区不同沉陷时期(1993、2000、2013年)9种类型生态系统服务价值进行核算。结果表明:①1993、2000和2013年鹤岗矿区生态系统的总服务价值量分别为2219.21、1025.15和3531.95万元。就生态系统而言,耕地的平均服务价值最高,占平均总价值的189.35%;其次是林地和水域,分别占平均总价值的46.50%和26.83%。②就生态系统服务类别而言,支持功能服务价值最高,平均价值量占平均总价值量的186.67%,其次是调节服务,占45.34%,文化服务占5.73%,供给服务占-137.74%。③1993-2013年,鹤岗矿区生态系统服务价值自西向东递增,这与采煤方向和开采程度差异有关。这种分布趋势主要受由采矿活动引起的土地利用类型、面积及质量变化的影响。④与无考虑空间异质性因素情况相比,1993、2000年鹤岗矿区生态系统服务总价值分别减少了152.96和580.12万元,2013年增加了781.63万元。随煤炭开采,1993-2013年鹤岗矿区采煤沉陷地自然生态环境状况呈现一个由下降到好转的过程。  相似文献   

14.
Growth rate as well as rate of glucose uptake of C. cryptica depends on glucose concentration in the medium according to saturation kinetics. The K g for growth is 1.9 × 10?5 M, and the K t, for glucose transport is 5.8 × 10?5 M. The maximum growth rate in the dark on glucose is considerably slower than the light-saturated growth rate at the same temperature, and does not appear to be determined by the capacity of the cell for glucose uptake. The glucose transport process is highly specific, and depends on energy metabolism. The Q 10 for the process is 2.2 (15–2.5 C). Glucose taken up by the cells is almost, quantitatively phosphorylated within 10 min, either through the transport process itself or by a high affinity kinase system in the cells.  相似文献   

15.
Varpe O  Fiksen O  Slotte A 《Oecologia》2005,146(3):443-451
Ecosystems are not closed, but receive resource subsidies from other ecosystems. Energy, material and organisms are moved between systems by physical vectors, but migrating animals also transport resources between systems. We report on large scale energy transport from ocean to coast by a migrating fish population, the Norwegian spring-spawning (NSS) herring Clupea harengus. We observe a rapid body mass increase during parts of the annual, oceanic feeding migration and we use a bioenergetics model to quantify energy consumption. The model predicts strong seasonal variation in food consumption with a marked peak in late May to July. The copepod Calanus finmarchicus is the most important prey and 23×106 tonnes (wet weight) of C. finmarchicus is consumed annually. The annual consumption-biomass ratio is 5.2. During the feeding migration 17% of consumed energy is converted to body mass. The biomass transported to the coast and left as reproductive output is estimated from gonad weight and is about 1.3×106 tonnes for the current population. This transport is to our knowledge the world’s largest flux of energy caused by a single population. We demonstrate marked temporal variation in transport during the last century and discuss the effects of NSS herring in the ocean, as a major consumer, and at the coast, where eggs and larvae are important for coastal predators. In particular, we suggest that the rapid decline of lobster Homarus gammarus landings in Western Norway during the 1960s was related to the collapse of NSS herring. We also discuss spatial variation in energy transport caused by changed migration patterns. Both climate and fisheries probably triggered historical changes in the migration patterns of NSS herring. New migration routes emerge at the level of individuals, which in turn determines where resources are gathered and delivered, and therefore, how meta-ecosystems function.  相似文献   

16.
All-atom molecular dynamics is used to investigate the transport of Na+ across a 1,2-dioleoyl-sn-glycero-3-phosphocholine lipid bilayer facilitated by a diazacrown hydraphile. Specifically, the free energy of Na+ passing through the bilayer is calculated using the adaptive biasing force method to study the free energy associated with the increase in Na+ transport in the presence of the hydraphile molecule. The results show that water interaction greatly influences Na+ transport through the lipid bilayer as water is pulled through the bilayer with Na+ forming a water channel. The hydraphile causes a reduction in the free energy barrier for the transport of Na+ through the head group part of the lipid bilayer since it complexes the Na+ reducing the necessity for water to be complexed and, therefore, dragged through with Na+, an energetically unfavorable process. The free energy associated with Na+ being desolvated within the bilayer is significantly decreased in the presence of the hydraphile molecule; the hydraphile increases the number of solvation states of Na+ that can be adopted, and this increase in the number of available configurations provides an entropic explanation for the success of the hydraphile.  相似文献   

17.
The importation of infected hosts and the arrival of windborne infected Culicoides (Diptera: Ceratopogonidae) were considered unlikely mechanisms for bluetongue virus (BTV) incursion into a BTV‐free area during the recent BTV serotype 8 (BTV‐8) epidemic in northern Europe. Therefore, alternative mechanisms need to be considered. Air, sea and land transport networks continue to expand, and an important consequence of this is vector‐borne pathogen importation. One important aspect of bluetongue (BT) epidemiology not yet addressed is the potential movement of infected Culicoides via transport and trade networks. Therefore, a risk assessment model was constructed to assess the probability of a BTV outbreak as a consequence of the introduction of Culicoides via these networks. The model was applied to calculate the risk for a BTV‐8 epidemic in Spain in 2007 caused by the introduction of Culicoides from affected northern European countries. The mean weighted annual risk for an outbreak caused by transportation of a single vector from an affected northern European country varied from 1.8 × 10?7 to 3.0 × 10?13, with the highest risks associated with Culicoides imported from Belgium, the Netherlands, Germany and France. For this mechanism to pose a significant risk to BTV‐free countries, a large number of vectors would have to be transported.  相似文献   

18.
After 50 years of coal mining, Huaibei Mine, located at 50 km southeast of Xuzhou City in East China, has grown to a middle-size city of 600,000 people from a small village of 2000 farmers. The Zhahe Valley, with 400 km2 of a built-up area and more than 100 km2 of subsided peri-urban wetland at the city center, is surrounded by eight exhausted old mines and communities. In cooperation with the local city government, an ecological landuse change assessment and eco-city planning project has been carried out with a focus on the assessment, restoration and enhancement of the wetland as an eco-service to the community. The assessment includes relationships to Green House Gas emissions and heat island effects, as well as measures for a livable, workable, affordable and sustainable human settlement development through industrial transition, landscape design and capacity building. This paper will briefly introduce the main ecological approaches and results of the assessment, including measures such as changing the car-dominated transportation network to a rail-dominated network, transforming the coal-oriented high-carbon industry to a service-oriented low-carbon industry, the C-shape urban form to an O-shape with a green–blue core at the center, and the fragmentized collapsed land to integrative eco-service land.  相似文献   

19.
ABSTRACT. Leishmania spp. are the causative agents of leishmaniasis, a complex of diseases with a broad spectrum of clinical manifestations. Leishmania (Leishmania) amazonensis is a main etiological agent of diffuse cutaneous leishmaniasis. Leishmania spp., as other trypanosomatids, possess a metabolism based significantly on the consumption of amino acids. However, the transport of amino acids in these organisms remains poorly understood with few exceptions. Glutamate transport is an important biological process in many organisms. In the present work, the transport of glutamate is characterized. This process is performed by a single kinetic system (Km=0.59±0.04 mM, Vmax=0.123±0.003 nmol/min per 20 × 106 cells) showing an energy of activation of 52.38±4.7 kJ/mol and was shown to be partially inhibited by analogues, such as glutamine, aspartate, α‐ketoglutarate and oxaloacetate, methionine, and alanine. The transport activity was sensitive to the extracellular concentration of H+ but not to Na+ or K+. However, unlike other amino acid transporters presently characterized, the treatment with specific ionophores confirmed the participation of a K+, and not H+ membrane gradient in the transport process.  相似文献   

20.
Locally produced bioenergy can decrease the dependency on imported fossil fuels in a region, while also being valuable for climate change mitigation. Short‐rotation coppice willow is a potentially high‐yielding energy crop that can be grown to supply a local energy facility. This study assessed the energy performance and climate impacts when establishing willow on current fallow land in a Swedish region with the purpose of supplying a bio‐based combined heat and power plant. Time‐dependent life cycle assessment (LCA) was combined with geographic information system (GIS) mapping to include spatial variation in terms of transport distance, initial soil organic carbon content, soil texture and yield. Two climate metrics were used [global warming potential (GWP) and absolute global temperature change potential (AGTP)], and the energy performance was determined by calculating the energy ratio (energy produced per unit of energy used). The results showed that when current fallow land in a Swedish region was used for willow energy, an average energy ratio of 30 MJ MJ?1 (including heat, power and flue gas condensation) was obtained and on average 84.3 Mg carbon per ha was sequestered in the soil during a 100‐year time frame (compared with the reference land use). The processes contributing most to the energy use during one willow rotation were the production and application of fertilizers (~40%), followed by harvest (~35%) and transport (~20%). The temperature response after 100 years of willow cultivation was ?6·10?16 K MJ?1 heat, which is much lower compared with fossil coal and natural gas (70·10?16 K MJ?1 heat and 35·10?16 K MJ?1 heat, respectively). The combined GIS and time‐dependent LCA approach developed here can be a useful tool in systematic analysis of bioenergy production systems and related land use effects.  相似文献   

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