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1.
Arbuscular mycorrhizae and phosphate solubilising bacteria of the rhizosphere of the mangrove ecosystem of Great Nicobar island, India 总被引：2，自引：0，他引：2
David Kothamasi Shalini Kothamasi A. Bhattacharyya Ramesh Chander Kuhad C. R. Babu 《Biology and Fertility of Soils》2006,42(4):358-361
Mangroves form an important ecosystem of Great Nicobar, a continental island in the Bay of Bengal with luxuriant tropical
rainforests. The rhizosphere of the mangrove plants of Great Nicobar was investigated for the presence of arbuscular mycorrhizal
fungus (AMF) and phosphate solubilising bacteria (PSB). The soils of the Great Nicobar mangroves were silt–clays and were
poor in phosphate content. Five species of AMF belonging to the genus Glomus were isolated. The %AMF colonization in the mangrove plants was between 0 and 17%, and the presence of AMF in the aerenchymatous
cortex suggests that the mangrove plants may be aiding in AMF survival by providing oxygen. Two strains of phosphate solubilising
Pseudomonas aeruginosa were found in the mangrove soils of Great Nicobar. Phosphate solubilisation by the two isolated strains was almost 70% under
in vitro conditions. PSB may play a role in the mangrove ecosystems of Great Nicobar by mobilising insoluble phosphate. The
plant roots could pick up the released phosphate directly or with the aid of AMF hyphae. 相似文献
2.
Local environmental conditions are a primary factor influencing chytridiomycosis, an emerging disease caused by the fungus Batrachochytrium dendrobatidis (Bd) that has affected over 200 amphibian species worldwide. In North America, seasonality and regional habitat differences predict considerable spatial and temporal disease variability, yet the sparse and opportunistic nature of most studies have provided insufficient data for understanding regional Bd epidemiology. We present a five-year field study that reveals spatial and temporal Bd dynamics across Lithobates yavapaiensis populations in Arizona, USA. Two populations showed no Bd infection or mortality, ten populations showed winter Bd infection, and five populations experienced winter mortality. Infection intensity decreased over winter sampling seasons, whereas mortality and infection prevalence did not change over time. Frogs dying from chytridiomycosis were significantly larger and had significantly higher infection intensities than survivors. We conclude that conserving L. yavapaiensis and other native amphibians requires protection and management of riparian ecosystems to promote populations large enough to survive winter cycles of chytridiomycosis. 相似文献
3.
The role of sediment microorganisms in the productivity, conservation, and rehabilitation of mangrove ecosystems: an overview 总被引：13，自引：1，他引：13
Mangrove communities are recognized as highly productive ecosystems that provide large quantities of organic matter to adjacent coastal waters in the form of detritus and live animals (fish, shellfish). The detritus serves as a nutrient source and is the base of an extensive food web in which organisms of commercial importance take part. In addition, mangrove ecosystems serve as shelter, feeding, and breeding zones for crustaceans, mollusks, fish of commercial importance, and resident and migratory birds. Although mangroves in the United States are protected, the systematic destruction of these ecosystems elsewhere is increasing. Deforestation of mangrove communities is thought to be one of the major reasons for the decrease in the coastal fisheries of many tropical and subtropical countries. There is evidence to propose a close microbe-nutrient-plant relationship that functions as a mechanism to recycle and conserve nutrients in the mangrove ecosystem. The highly productive and diverse microbial community living in tropical and subtropical mangrove ecosystems continuously transforms nutrients from dead mangrove vegetation into sources of nitrogen, phosphorus, and other nutrients that can be used by the plants. In turn, plant-root exudates serve as a food source for the microorganisms living in the ecosystem with other plant material serving similarly for larger organisms like crabs. This overview summarizes the current state of knowledge of microbial transformations of nutrients in mangrove ecosystems and illustrates the important contributions these microorganisms make to the productivity of the ecosystems. To conserve the mangrove ecosystems, which are essential for the sustainable maintenance of coastal fisheries, maintenance and restoration of the microbial communities should be undertaken. Inoculation of mangrove seedlings with plant-growth-promoting bacteria may help revegetate degraded areas and create reconstructed mangrove ecosystems. 相似文献
4.
Ángel Guerra Ángel F. González Santiago Pascual Earl G. Dawe 《Biological conservation》2011,(7):1989-1997
The current public perception is that there is little reason for concern for the conservation of marine invertebrates, in part due to the scarcity of emblematic species to represent that diverse group. This paper shows that giant squid can be considered an emblematic species to represent concern for the conservation of marine invertebrate biodiversity because it satisfies all the requirements of an emblematic species. It shows that Architeuthis attracts public interest and attention and can serve as an indicator of oceanographic conditions and ocean climate change. It asserts that Architeuthis can represent concerns for vulnerable marine ecosystems associated with submarine canyons and that it belongs to a broad diverse phylogenetic group of organisms associated with these canyons, sharing common concerns with that group with respect to vulnerability and conservation. This study also advocates that the giant squid can serve as an indicator of effects of ecosystem stress resulting from anthropogenic effects including ocean acidification and warming. It is also shown to be vulnerable to such anthropogenic effects as fishing, acoustic seismic exploration and, possibly, pollutants. 相似文献
5.
《Soil Science and Plant Nutrition》2012,58(5):435-443
ABSTRACTMangrove ecosystems play an important role in carbon (C) accumulation in tropical and subtropical regions. Below-ground deep anoxic soil is especially important for C accumulation. However, quantitative data on below-ground soil C stocks in mangrove ecosystems are lacking compared with data on above-ground biomass. In addition, soil C accumulation processes in mangrove ecosystems have not been sufficiently clarified. In this study, we quantified soil C stocks and focused on the mass of fallen litter and below-ground roots, which are produced by tree and that may directly influence soil C stocks in a mature subtropical mangrove in the estuary of Fukido River, Ishigaki Island, southwestern Japan. The principal species in this study site were Bruguiera gymnorhiza and Rhizophora stylosa, and total above-ground biomass at the site was 80.7 ± 1.3 (mean ± SD) Mg C ha?1 over the period from 2014 to 2016. Litter was collected in six litter traps from May 2013 to November 2016, it ranged from 7.8 to 11.5 Mg C ha?1, with the major proportion of litter being from foliage (leaves and stipules). The root C density at 90-cm depth was 27.1 ± 11.3 Mg C ha?1. The soil C stock in the mangrove forest at a depth of 90 cm at the study site was 251.0 ± 34.8 Mg C ha?1, and it seems to be lower value in the tropical region but it to be higher in subtropical East Asian mangrove sites. Dead roots, especially dead fine roots, but not fallen litter, were significantly positively correlated with soil C stocks. The δ13C values obtained from soils ranged from ?29.3‰ to ?27.0‰; these values are consistent with those for below-ground fine roots. These results strongly suggest that dead fine roots could be a main factor controlling soil C stocks at this study site. 相似文献
6.
Carbon sinks in mangroves and their implications to carbon budget of tropical coastal ecosystems 总被引：1，自引：0，他引：1
Nearly 50% of terrigenous materials delivered to the world's oceans are delivered through just twenty-one major river systems. These river-dominated coastal margins (including estuarine and shelf ecosystems) are thus important both to the regional enhancement of productivity and to the global flux of C that is observed in land-margin ecosystems. The tropical regions of the biosphere are the most biogeochemically active coastal regions and represent potentially important sinks of C in the biosphere. Rates of net primary productivity and biomass accumulation depend on a combination of global factors such as latitude and local factors such as hydrology. The global storage of C in mangrove biomass is estimated at 4.03 Pg C; and 70% of this C occurs in coastal margins from 0° to 10° latitude. The average rate of wood production is 12.08 Mg ha?1 yr?1, which is equivalent to a global estimate of 0.16 Pg C/yr stored in mangrove biomass. Together with carbon accumulation in mangrove sediments (0.02 Pg C/yr), the net ecosystem production in mangroves is about 0.18 Pg C/yr. Global estimates of export from coastal wetlands is about 0.08 Pg C/yr compared to input of 0.36 Pg C/yr from rivers to coastal ecosystems. Total allochthonous input of 0.44 Pg C/yr is lower than in situ production of 6.65 Pg C/yr. The trophic condition of coastal ecosystems depends on the fate of this total supply of 7.09 Pg C/yr as either contributing to system respiration, or becoming permanently stored in sediments. Accumulation of carbon in coastal sediments is only 0.41 Pg C/yr; about 6% of the total input. The NEP of coastal wetlands also contribute to the C sink of coastal margins, but the source of this C is part of the terrestrial C exchange with the atmosphere. Accumulation of C in wood and sediments of coastal wetlands is 0.205 Pg C/yr, half the estimate for sequestering of C in coastal sediments. Burial of C in shelf sediments is probably underestimated, particularly in tropical river-dominated coastal margins. Better estimates of these two C sinks in the tropics, coastal wetlands and shelf sediments, is needed to better understand the contribution of coastal ecosystems to the global carbon budget. 相似文献
7.
8.
Freshwaters ecosystems continue to face pressures from pollution, flow regime alterations, habitat destruction and exotic species invasions despite their unique biodiversity. In Europe, National Parks and Special Areas of Conservation aim to provide protection of ‘aggregate’ biodiversity, yet inspection of priority species lists for these sites often reveals a focus towards terrestrial species. In regions such as the Alps and the Pyrénées, this is a particularly serious problem because climate change and other anthropogenic pressures (e.g. hydropower, tourism) are causing widespread hydrological modification which is likely to drive changes in aquatic species abundance, diversity and distribution. Improved understanding of the diversity of rare plants and animals is necessary so efforts can be cost-effectively targeted to conserve the maximum number of species, whilst a clearer picture of these species’ distributions is a precursor to targeting conservation efforts. This paper reports results of a study into the diversity and distribution of 17 endemic mayflies, stoneflies and caddisflies from 598 rivers sites across southern France. Endemic macroinvertebrates were found only at sites in the Pyrénées mountain range with richness peaking at 1500–1800 m above sea level. Nine of these 17 species were recorded from <20 sites and two (Protonemura angelieri, Rhithrogena kimminsi) were found at only 10 sites. Despite both the rarity of these species and threats to their existence, none of them have any current conservation status. New conservation policies for freshwater ecosystems in the French Pyrénées need to be developed as a priority due to the rarity of many aquatic species in this area, growing threats to their existence (habitat modification, hydrological change), and to recognise their importance in food webs that may include other rare species of conservation value. 相似文献
9.
Garnett Erin Jonsson Lena M. Dighton John Murnen Katherine 《Biology and Fertility of Soils》2004,40(6):421-426
We investigated the influence of three concentrations of water extracts of three leaf litter species (pitch pine, huckleberry and white oak) and a mixture of all litters on the germination of pitch pine seeds and initial seedling growth in a microcosm experiment. All three plant species are important components of the pine barrens ecosystems in New Jersey, where it has been seen that pine seedling recruitment occurs only after stand replacing fire or in disturbed sites, where surface organic soil horizons and leaf litter have been removed. Leaf litter extracts did not influence seed germination, but significantly reduced seedling growth at high concentrations. There was little difference between the leaf litter species in growth suppression. As charcoal is a natural residue on the forest floor following fire, its influence on growth suppression was examined; it has been shown to immobilize polyphenols. Charcoal removed the inhibitory effect of leaf litter extracts and allowed the fertilizer effect of nutrients leached from the leaves to enhance seedling growth, particularly at the higher concentration of litter extract used. Responses to litter extracts were compared to four pure phenolic compounds, catchecol, p-coumaric acid, p-hydroxybenzoic acid and tannic acid. None of these compounds suppressed pine seedling growth, suggesting that these phenolics are not allelopathic to pine seedlings. The results are discussed in the context of fire as a driving factor in these oligotrophic and seasonally dry ecosystems and the interactions between nutrient supply and allelopathic chemistry of different leaf litters. 相似文献
10.
A. Nicholas E. Birch Bryan S. Griffiths Sandra Caul Jacqueline Thompson Lars H. Heckmann Paul H. Krogh Jrme Cortet 《Pedobiologia》2007,51(3):251-ECOGEN
The interactions of genetically modified (GM) crops with soil species and ecosystems is complex, requiring both specific and broad spectrum assessments. In the ECOGEN project we undertook experiments at three scales of increasing complexity, using Bt maize expressing the Cry1Ab protein from Bacillus thuringiensis as an example. Test species were selected for laboratory-scale experiments to represent taxonomic groups that we could also monitor at glasshouse and field scales (e.g., nematodes, protozoa, micro-arthropods, earthworms, and snails). In the laboratory, single species were exposed to purified Cry1Ab protein or to Bt maize leaf powder incorporated into simplified diets under controlled conditions. In the glasshouse, multiple test species and soil microbial communities taken from ECOGEN's field sites were exposed to Bt maize plants growing under glasshouse or mesocosm conditions. In the field, evaluations were conducted on our selected indicator groups over multiple sites and growing seasons. Field evaluation included assessment of effects due to the local environment, crop type, seasonal variation and conventional crop management practice (tillage and pesticide use), which cannot be assessed in the glasshouse. No direct effects of Cry1Ab protein or Bt leaf residues were detected on our laboratory test organisms, but some significant effects were detected in the glasshouse. Total nematode and protozoan numbers increased in field soil under Bt maize relative to conventional maize, whilst microbial community structure and activity were unaffected. Field results for the abundance of nematodes and protozoa showed some negative effects of Bt maize, thus contradicting the glasshouse results. However, these negative results were specific to particular field sites and sampling times and therefore were transient. Taking the overall variation found in maize ecosystems at different sites into account, any negative effects of Bt maize at field scale were judged to be indirect and no greater than the impacts of crop type, tillage and pesticide use. Although the ECOGEN results were not predictive between the three experimental scales, we propose that they have value when used with feedback loops between the scales. This holistic approach can used to address questions raised by results from any level of experimentation and also for putting GM crop risk:benefit into context with current agricultural practices in regionally differing agro-ecosystems. 相似文献
11.
Annie Melinda Paz-Alberto Arnel B. Celestino Gilbert C. Sigua 《Journal of Soils and Sediments》2014,14(1):251-258
Purpose
Coal-fuelled power plants can discharge hazardous materials, particularly heavy metals such as lead (Pb). An alternative way of reducing Pb concentration from contaminated sediments is through phytoremediation. Presently, there are few research findings on the phytoremediation potential of mangroves on metals like Pb. The study was conducted to survey and identify mangroves that thrive near the coal-fired power plant and to assess the phytoremediation potential of mangroves on Pb in sediment.Materials and methods
The study sites were located in the mangrove ecosystems of Sitio Oyon and Sitio Asinan in Masinloc, Zambales, Philippines. The first stage of our study was to survey and identify the mangrove species. The second stage was to assess the levels of Pb in the sediments, water, and tissues of mangrove trees. The diversity assessment of the mangrove species was done through the use of 10?×?12 m quadrat technique. Water and sediment samples from each mangrove ecosystem were collected using composite sampling methods.Results and discussion
Three mangrove species were identified in the study sites: Avicennia marina, Rhizophora stylosa, and Sonneratia alba. The order of importance of the mangrove trees in the two sampling locations, based on an importance value index (IVI), were as follows: SA (IVI?=?171.20)?>?AM (77.79)?>?RS (51.01). The total uptake of Pb from sediments near the power plants varied significantly (p?≤?0.001) among the three mangrove species. S. alba had the highest Pb uptake of 48.4 kg ha?1 followed by A. marina (23.1 kg ha?1), and R. stylosa (2.4 kg ha?1). These three mangrove species have the potential to phytoremediate Pb in the sediment.Conclusions
The three mangrove species present in the coastal ecosystem near the electric power plant—A. marina, R. stylosa, and S. alba—were potential phytoremediators of sediment Pb. The present study indicated that the mangroves possess beneficial characteristics that remove Pb from contaminated sediments in areas directly affected by coal-fired power plants, and thus have potential phytoremediation properties. 相似文献12.
Gonzalo Machado-Schiaffino Francis Juanes Eva Garcia-Vazquez 《Biological conservation》2011,(1):330-338
Identification of areas which should be a subject of protection is crucial for safeguarding the marine ecosystems. Amongst the reasons for protecting a region or location, the existence of unique populations or evolutionary significant units for one or more key species is a priority. The North American silver hake, Merluccius bilinearis, is currently managed as two stocks (northern and southern) without considering gulf areas separately. Employing microsatellite and mitochondrial markers we have detected significant FST values between hake individuals inhabiting gulfs and those distributed in the open sea, and asymmetric gene flow, higher from the gulf to the open sea than in the opposite direction. These differences can be interpreted as signals of separate populations in gulfs which may act as sources of variability for hake species. Occurrence of similar phenomena in Atlantic waters in both the northern and the southern Hemisphere, for these two pelagic–demersal hake species, suggests that gulfs may constitute a target for designing marine protected areas and confirms the adequacy of gulf-specific management already employed in Argentina. 相似文献
13.
Bamboo has been introduced to coastal sandy areas in southeastern China to protect and restore coastal ecosystems. An understanding of the chemistries and enzymatic and microbial activities in the soils of these bamboo forests will aid our understanding of how bamboo plantations can improve soil fertility and will provide scientific evidence for policy makers for encouraging the planting of bamboo in other coastal areas. We investigated the physical and chemical properties of the rhizosphere soil [soil moisture content (SMC), pH, and contents of soil organic matter (SOM), total nitrogen (TN), available nitrogen (AN), total phosphorus (TP), available phosphorus (AP), total potassium (TK) and available potassium (AK)], enzymatic activities (sucrase, protease, urease and catalase) and microbial properties (counts of bacteria, fungi and actinomycetes) in five bamboo forests. The bamboo forests had significantly higher levels of SOM, TN, AN, TP, AP, TK, and AK and lower pH relative to a control soil sample from an area devoid of plants. Soil enzymatic activities and microbial communities were considerably higher in the bamboo forests than in the soil from the barren land. The chemical contents, enzymatic activities and microbial counts of the soil and the litter and root biomasses were higher in forests with the bamboo species Dendrocalamopsis oldhami and Pseudosasa amabilis than in forests with the other three species (Acidosasa edulis, Dendrocalamopsis vario-striata, and Dendrocalamopsis beecheyana var. pubescens), which suggests that these two species could adapt to sandy soil and grow well in a hostile environment. These results indicate that planting bamboo may help to both enrich soil fertility and increase the diversity of tree species in coastal ecosystems. The difference between aboveground and belowground biomass may have been responsible for these changes in soil properties. 相似文献
14.
Uphill shifts of alpine species have been associated with climate warming; however, land-use change can act simultaneously. We surveyed two related alpine burnet moth species in the Pyrenees to determine whether there was an uphill shift in the range of these two species and, if so, whether this was driven by climate and/or land-use changes. In 2008/09 we revisited 28 sites at the lower altitudinal range limits at which the species had been recorded between 1958 and 1986 (data were obtained from museum collections, distribution atlas, researchers’ field notes). We also recorded the recent upper range limits. The arctic-alpine Zygaena exulans showed an uphill shift (148 m ± SD 87 m/decade) at all sites; at four sites the species has even become extinct. Changes in the lower altitudinal range limits were attributed to climate change. For the endemic species Zygaena anthyllidis we only ascertained an uphill shift at one third of the sites investigated (60 m ± SD 74 m/decade); these shifts were due to changes in grazing intensities. As both species colonize very high summits, further uphill shifts of the upper limits are no longer possible. The studied con-generic species are affected by different global change drivers. Our data indicate the considerable role of land-use in conservation and suggest that it can even exceed the impact of climate change. Ongoing climate change is likely to jeopardize the long-term survival of Z. exulans in the Pyrenees; Z. anthyllidis, however, may be preserved by appropriate management in the subalpine belt. 相似文献
15.
The State of Kuwait has initiated an ambitious national program to establish greenery in 20000 ha of open spaces in inland and coastal areas. Afforestation of intertidal zones with mangrove plants is being considered as a viable option for greening coastal areas. In view of this fact, experimental plantations were established using two ecotypes of Avicennia marina (Bahrain and UAE) and one ecotype of Avicennia germinans (Florida). The study consisted of two 10-year old plantations and two 2-year old plantations. Seedlings established successfully and grew vigorously on some of the locations within the site. Therefore, studies were conducted during 2002-2003 to describe and classify soils that supported maximum mangrove establishment and growth under the harsh arid coastal conditions of Kuwait. For this purpose, eight soil profiles (four each representing areas where seedlings established successfully and grew vigorously and where all seedlings died in the initial stages of establishment) were investigated and classified according to the soil taxonomy. The main soil types observed in the study site were: Typic Aquisalids, Typic/sodic Aquicambids and Calcic Aquisalids. Mangrove growth performance in relation to the landform, soil type and properties of the soil at various depths is discussed in the paper. The plant growth appeared to be the better on the typic Aquisalid soil than that on the Typic/sodic Aquicambid soils. The relative proportions of the coarse sand fraction, occurrence of the anaerobic layer in the profile and the surface layer salinity influenced both the establishment and growth of mangrove plants. 相似文献
16.
Exploration of <Emphasis Type="Italic">Vernonia galamensis</Emphasis> in Ethiopia,and Variation in Fatty Acid Composition of Seed Oil 总被引：1，自引：0，他引：1
Vernonia galamensis is a new potential industrial crop with very high content of vernolic acid in the seed oil. The species is known to naturally
grow as a weed in fields or in woodlands under a wide range of agroecological conditions of Africa. In order to study the
existing variability in Ethiopia, germplasm collection was carried out. Vernonia grows wild in various ecosystems. Ten regions were explored from North, South, East, Southeast, Southwest and Central Ethiopia.
A diverse range of habitats having different altitudes and ecological conditions was explored. Altitude of collecting sites
varied between 1250 and 2050 m, and soil pH from 5.1 to 8.5. The most common soil type was sandy loam, and the organic matter
content varied from 0.2% to 12.9%. At 80 sites, about 480 accessions were collected including different maturity time, plant
type, flower color, and branching patterns as well as fatty acid composition. The mean vernolic acid content of the seed oil
of the accessions was 74%, and ranged from 34% to 87%. A wide variability in composition of other fatty acids was observed.
It was not possible to find Vernonia in some locations that were earlier indicated by herbarium specimens collected since 1840. This could be a sign of change
in land use system and environmental degradation and, hence, loss of genetic resources of the species. 相似文献
17.
Morphological and molecular diversity analysis among the Indian clones of <Emphasis Type="Italic">Sesuvium portulacastrum</Emphasis> L. 总被引：1，自引：1，他引：0
Vinayak H. Lokhande Tukaram D. Nikam Vikas Y. Patade Penna Suprasanna 《Genetic Resources and Crop Evolution》2009,56(5):705-717
Sesuvium portulacastrum L. (seapurslane) is a halophyte used as pioneer species in sand dune fixation and stabilization of saline soil. Studies on
the morphological and molecular diversity were carried out for the 14 clones of Sesuvium collected from the different coastal regions of India. Significant differences were observed for morphological traits viz.,
length, width, diameter and area of leaf, internodal distance and stem diameter for different clones when compared with the
clone from Gujarat state (GJ1). A UPGMA dendrogram for morphological traits based on the Pearson’s similarity coefficient
clustered the clones into three groups considering 80% polymorphism as criteria. Molecular diversity among the clones was
studied using Randomly Amplified Polymorphic DNA (RAPD), Internal Transcribed Spacer (ITS) and markers specific to Ac homologous region. Of the total 749 RAPD loci amplified with 70 random primers, 294 were polymorphic with 39.25% diversity.
A phylogenetic tree constructed with UPGMA and SHAN, grouped the clones into three major clades based on RAPD data. The molecular
diversity studied with ITS and markers specific to Ac homologous region revealed 37.50% and 66.66% polymorphism and clustered the clones into three and four clades, respectively.
The genetic diversity analysis revealed wide variations among the S. portulacastrum clones, reflecting a high level of diversity within the species which might be due to anthropogenic impact and geographic
environmental conditions. Further, the various clones from the different eco-geographic coastal localities might have originated
from native places of wild abundance. To the best of our knowledge, this is the first attempt to evaluate both morphological
and genetic diversity among the Sesuvium clones collected from the distant habitats of the coastal regions of the India. 相似文献
18.
Vinayak Haribhau Lokhande Tukaram Dayaram Nikam Penna Suprasanna 《Genetic Resources and Crop Evolution》2009,56(5):741-747
Seapurslane, Sesuvium portulacastrum (L.) L. (Aizoaceae) is a pioneer, psammophytic facultative halophyte naturally growing in the subtropical, mediterranean,
coastal and warmer zones of the world. The plant is utilized as a vegetable by the local peoples as well as forage for domestic
animals in the coastal area. Environmentally, it is utilized for the bioreclamation of saline soil in the arid and semiarid
regions and an alternative culture to problematic soils. The Sesuvium clones collected from the coastal regions of India lead to conclusions with respect to its geographical distribution and
prospective utilization in the bioremediation of coastal and saline areas, as an emerging source of secondary metabolite-phytoecdysteroids
in sericulture industry and cultivation on large scale for food as well as forage, of this underutilized, neglected wild and
also cultivated plant species. 相似文献
19.
Cristiane Cipola Fasanella Armando Cavalcante Franco Dias Janaina Rigonato Marli de Fátima Fiore Fábio Lino Soares Jr Itamar Soares Melo Aline Aparecida Pizzirani-Kleiner Jan Dirk van Elsas Fernando Dini Andreote 《Water, air, and soil pollution》2012,223(7):4233-4243
Mangrove ecosystems are tropical environments that are characterized by the interaction between the land and the sea. As such, this ecosystem is vulnerable to oil spills. Here, we show a culture-independent survey of fungal communities that are found in the sediments of the following two mangroves that are located on the coast of Sao Paulo State (Brazil): (1) an oil-spill-affected mangrove and (2) a nearby unaffected mangrove. Samples were collected from each mangrove forest at three distinct locations (transect from sea to land), and the samples were analyzed by quantitative PCR and internal transcribed spacer (ITS)-based PCR-DGGE analysis. The abundance of fungi was found to be higher in the oil-affected mangrove. Visual observation and correspondence analysis (CA) of the ITS-based PCR-DGGE profiles revealed differences in the fungal communities between the sampled areas. Remarkably, the oil-spilled area was quite distinct from the unaffected sampling areas. On the basis of the ITS sequences, fungi that are associated with the Basidiomycota and Ascomycota taxa were most common and belonged primarily to the genera Epicoccum, Nigrospora, and Cladosporium. Moreover, the Nigrospora fungal species were shown to be sensitive to oil, whereas a group that was described as ??uncultured Basidiomycota?? was found more frequently in oil-contaminated areas. Our results showed an increase in fungal abundance in the oil-polluted mangrove regions, and these data indicated potential fungal candidates for remediation of the oil-affected mangroves. 相似文献
20.
Natural CO2 sinks in terrestrial and marine environments are important components of the global carbon cycle, yet the sign and magnitudes of key fluxes among them are unknown. The results of the Palmas Del Mar Workshop — Natural Sinks of CO2 presented in this special issue and its companion hardbound volume of Water, Air, & Soil Pollution, provide a synthesis of current research on the carbon cycle, CO2 sinks and associated processes and fluxes, and critical research needs to assess the potential role of forest and land-use management in carbon sequestration. The papers in this volume present data, observations, and model simulations that demonstrate: 1) the existence of natural CO2 sinks that could mitigate a significant amount of CO2 emissions from fossilfuel combustion; 2) probable, human-caused imbalances in C exchanges among vegetation, soils, and the atmosphere; 3) enhanced C storage in vegetation in response to excess atmospheric CO2; 4) strong interactions among carbon, nutrient and hydrological cycles; and 5) an excess of carbon production over consumption in several, large managed forests. Although it appears unlikely that the search for the “missing” C sink required to balance the C budget will end in the open ocean, new estimates of C storage in mangrove wood and peat, suggest that coastal ecosystems have the capacity to store significant amounts of carbon in vegetation and sediments. Convincing analyses are also presented indicating the technical and economical feasibility of managing existing lands to sequester additional carbon. Long-term field studies of CO2 fertilization effects and carbon cycling by plants and soils in geographically important systems, native forests, and coastal ecosystems will go a long way toward meeting the research needs identified at the workshop. 相似文献