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1.
The afforestation of arid lands faces many challenges, and perhaps the most important key for success is choosing one or more species that are adapted well for local environmental conditions. We explored species that would be suitable for the steppe region of Central Anatolia. Intensive site preparation included ripping the subsoil (to 80 cm) and plowing the upper soil before planting seedlings of Elaeagnus angustifolia, Robinia pseudoacacia, Fraxinus angustifolia, and Pinus nigra were used as tree species. We also tested the success of several shrub species: Amygdalus orientalis, Calligonum polygonoides, and Spartium junceum. After five growing seasons, E. angustifolia showed the highest survival, with 80% of planted seedlings remaining. For the shrubs, A. orientalis was the most successful species with a 95% survival rate. Broad-leaved trees grew a cumulative average of 34 cm in height in 5 years, whereas P. nigra seedings grew only 9 cm. The greatest height growth occurred in the shrubs, with A. orientalis gaining 40 cm in height in 5 years. Overall, E. angustifolia and A. orientalis appeared best suited for afforestation in these areas. R. pseodoacacia and F. angustifolia may also be used as alternative species.  相似文献   

2.
A total of 285 water samples were collected from 71 roof harvested rainwater tanks from four villages in different provinces over a two-year (2013–2014) period during the early (October to December) and late (January to March) rainy season. Water quality was evaluated based on Escherichia coli, faecal coliforms and Enterococcus spp. prevalence using the IDEXX Quanti-Tray quantification system. Real-Time PCR was used to analyse a subset of 168 samples for the presence of Shigella spp., Salmonella spp. and E. coli virulence genes (stx1, stx2 and eaeA). Escherichia coli were detected in 44.1% of the samples, Enterococcus spp. in 57.9% and faecal coliforms in 95.7%. The most prevalent E. coli concentrations in harvested rainwater were observed in 29.1% of samples and 22.5% for Enterococcus spp. and, were within 1–10 cfu/100 ml and 10–100 cfu/100 ml, respectively, whereas those for faecal coliforms (36.6%) were within 100–1000 cfu/100 ml. On average 16.8% of the samples had neither E. coli nor Enterococcus spp. detected, while 33.9% had only Enterococcus spp. and 23.7% had only E. coli. E. coli and Enterococcus spp. were detected together in 25.5% of the samples. Evaluation of samples for potential pathogenic bacteria showed all tested samples to be negative for the Shigella spp. ipaH gene, while five tested positive for Salmonella ipaB gene. None of the samples tested positive for the stx1 and stx2 genes, and only two tested positive for the eaeA gene. These findings are potentially useful in the development of a simplified risk assessment strategy based on the concentrations of indicator bacteria.  相似文献   

3.
Th aim of this study is to investigate spatio-temporal trends of dengue vector breeding and epidemic (disease incidence) influenced by climatic factors. The spatio-temporal (low-, medium-, and high-intensity periods) evaluation of entomological and epidemiological investigations along with climatic factors like rainfall (RF), temperature (Tmax), relative humidity (RH), and larval indexing was conducted to develop correlations in the area of Lahore, Pakistan. The vector abundance and disease transmission trend was geo-tagged for spatial insight. The sufficient rainfall events and optimum temperature and relative humidity supported dengue vector breeding with high larval indices for water-related containers (27–37%). Among temporal analysis, the high-intensity period exponentially projected disease incidence followed by post-rainfall impacts. The high larval incidence that was observed in early high-intensity periods effected the dengue incidence. The disease incidence had a strong association with RF (r = 0.940, α = 0.01). The vector larva occurrence (r = 0.017, α = 0.05) influenced the disease incidence. Similarly, RH (r = 0.674, α = 0.05) and average Tmax (r = 0.307, α = 0.05) also induced impact on the disease incidence. In this study, the vulnerability to dengue fever highly correlates with meteorological factors during high-intensity period. It provides area-specific understanding of vector behavior, key containers, and seasonal patterns of dengue vector breeding and disease transmission which is essential for preparing an effective prevention plan against the vector.  相似文献   

4.
Microplankton population of Asia’s largest coastal lagoon Chilika was studied for five major groups, bacillariophyceae, cyanophyceae, chlorophyceae, dinophyceae, rotifera, and tintinninae. The study reported presence of 233 species of microplankton whose average annual abundance was 1631 cells/l. The physicochemical parameters contributing to the spatio-temporal fluctuations in microplankton diversity, abundance, and community structure were identified as salinity, pH, DO, nitrate, and silicate. Salinity, transparency, depth, and silicate most explained the abundance of bacillariophyceae; nitrate, pH, and DO influenced cyanophyceae; salinity, transparency, and chlorophyll concentration influenced chlorophyceae; salinity, depth, and water temperature influenced dinophyceae; salinity, free CO2, and nitrate-influenced rotifers, whereas salinity, pH, DO, and depth influenced tintinnids. Biotic-abiotic relationships revealed particular preference of environmental conditions at species level in groups like bacillariophyceae, cyanophyceae, and dinophyceae. Although the lagoon is shallow, bacillariophyceae-environment interaction showed depth can be a critical factor for species like Aulocoseira sp., Amphipleura sp., and Rhophalodia sp. Species of dinoflagellates like Dinophysis caudata, Noctiluca scintillans, and Protoperidinium proliferated in lower level of silicate. Unlike other cyanophyceae species Streptococcus sp., Chroococcus sp., Diplococcus sp., Aphanocapsa sp., and Gloeocapsa sp. were negatively influenced by nitrate concentration. The study provides better scope for ecological management of the lagoon with respect to conserving biodiversity and hydrological quality of the ecosystem.  相似文献   

5.
Storm water runoff is increasingly assessed for fecal indicator organisms (e.g., Escherichia coli, E. coli) and its impact on contact recreation. Concurrently, use of autosamplers along with logistic, economic, technical, and personnel barriers is challenging conventional protocols for sample holding times and storage conditions in the field. A common holding time limit for E. coli is 8 h with a 10 °C storage temperature, but several research studies support longer hold time thresholds. The use of autosamplers to collect E. coli water samples has received little field research attention; thus, this study was implemented to compare refrigerated and unrefrigerated autosamplers and evaluate potential E. coli concentration differences due to field storage temperature (storms with holding times ≤24 h) and due to field storage time and temperature (storms >24 h). Data from 85 runoff events on four diverse watersheds showed that field storage times and temperatures had minor effects on mean and median E. coli concentrations. Graphs and error values did, however, indicate a weak tendency for higher concentrations in the refrigerated samplers, but it is unknown to what extent differing die-off and/or regrowth rates, heterogeneity in concentrations within samples, and laboratory analysis uncertainty contributed to the results. The minimal differences in measured E. coli concentrations cast doubt on the need for utilizing the rigid conventional protocols for field holding time and storage temperature. This is not to say that proper quality assurance and quality control is not important but to emphasize the need to consider the balance between data quality and practical constraints related to logistics, funding, travel time, and autosampler use in storm water studies.  相似文献   

6.
Much of the terrestrial biodiversity in sub-Saharan Africa is supported by tropical rainforest. Natural resource development, particularly surface mining in the rainforest, poses great risks to the region’s rich and endemic biodiversity. Here, we assessed the impact of surface mining and the success of forest rehabilitation on small mammal diversity in the Western Region of Ghana. We surveyed small mammals in the project area and two adjoining forest reserves (control sites) before the mining operation and 10 years after mine closure and forest rehabilitation (topsoil replacement and revegetation). The forest reserves recorded higher species abundance than the mining areas. Majority of the species captured in the forest reserves, including Hylomyscus alleni, Praomys tullbergi, Malacomys cansdalei, and Hybomys trivirgatus, are forest obligate species. Only one individual each of H. alleni and P. tullbergi was captured in the naturally regenerated areas (core areas of mining activities that were allowed to revegetate naturally), while 32 individuals belonging to four species (Lophuromys sikapusi, Mus musculoides, Mastomys erythroleucus, and Crocidura olivieri) were recorded in the rehabilitated areas. Our data suggested negative effects of mining on small mammal diversity and the restoration of species diversity and important ecological processes after rehabilitation of altered habitats. We strongly encourage deliberate conservation efforts, particularly the development of management plans that require the restoration of degraded land resulting from mining activities.  相似文献   

7.
The zebrafish (Danio rerio) is one of the most studied aquatic organisms for water biomonitoring, due to its sensitivity to environmental degradation and resistance to toxic substances. This study determined the presence of micronuclei and nuclear abnormalities in peripheral blood erythrocytes, and assessed the gene expression of caspase-3 (CASP-3) and metallothionein 1 (MT-1) in the gills and liver of D. rerio. The study fish (n = 45) were exposed to water collected from two stations with mining impact (E2 and E3) and a reference station without evident mining contamination (E1), all located in La Elvira stream (Manizales-Colombia). In addition, a positive control (PC) with HgCl2 (50 μg/L) and negative control (NC) with tap water were included. The fish from the PC and E2 and E3 treatments displayed genotoxic effects and changes in gene expression, with significant differences in micronuclei formation and the presence of blebbed nuclei. The cytochrome oxidase subunit I (COI) gene was used as reference and proved to be stable compared to the β-actin and 28S ribosomal RNA (28S) genes. In gills, CASP-3 expression was higher in the PC, and MT-1 expression was higher in the PC and E3 treatment. In liver, CASP-3 was expressed in the E2 treatment, and MT-1 expression was low. These results show that the genotoxic effects and differential gene expression observed in fish exposed to water from La Elvira stream could also be affecting the organisms present in this habitat.  相似文献   

8.
Vibrio species isolated from four different sampling stations in the west coast of Peninsular Malaysia were screened for their antimicrobial resistance and plasmid profiles. A total of 138 isolates belonging to 15 different species were identified. Vibrio campbellii, V. parahaemolyticus, V. harveyi, and V. tubiashii were found to predominance species at all stations. High incidence of erythromycin, ampicillin, and mecillinam resistance was observed among the Vibrio isolates. In contrast, resistance against aztreonam, cefepime, streptomycin, sulfamethoxazole, and sulfonamides was low. All the Vibrio isolates in this study were found to be susceptible to imipenem, norfloxacin, ofloxacin, chloramphenicol, trimethoprim/sulfamethoxazole, and oxytetracycline. Ninety-five percent of the Vibrio isolates were resistant to one or more different classes of antibiotic, and 20 different resistance antibiograms were identified. Thirty-two distinct plasmid profiles with molecular weight ranging from 2.2 to 24.8 kb were detected among the resistance isolates. This study showed that multidrug-resistant Vibrio spp. were common in the aquatic environments of west coast of Peninsular Malaysia.  相似文献   

9.
The poor operational status of some wastewater treatment plants often result in the discharge of inadequately treated effluent into receiving surface waters. This is of significant public health concern as there are many informal settlement dwellers (ISDs) that rely on these surface waters for their domestic use. This study investigated the treatment efficiency of two independent wastewater treatment plants (WWTPs) in Durban, South Africa and determined the impact of treated effluent discharge on the physicochemical and microbial quality of the receiving water bodies over a 6-month period. Presumptive Escherichia coli isolates were identified using biochemical tests and detection of the mdh gene via PCR. Six major virulence genes namely eae, hly, fliC, stx1, stx2, and rfbE were also detected via PCR while antibiotic resistance profiles of the isolates were determined using Kirby-Bauer disc diffusion assay. The physicochemical parameters of the wastewater samples ranged variously between 9 and 313.33 mg/L, 1.52 and 76.43 NTUs, and 6.30 and 7.87 for COD, turbidity, and pH respectively, while the E. coli counts ranged between 0 and 31.2?×?103 CFU/ml. Of the 200 selected E. coli isolates, the hly gene was found in 28 %, fliC in 20 %, stx2 in 17 %, eae in 14 %, with stx1 and rfbE in only 4 % of the isolates. Notable resistance was observed toward trimethoprim (97 %), tetracycline (56 %), and ampicillin (52.5 %). These results further highlight the poor operational status of these WWTPs and outline the need for improved water quality monitoring and enforcement of stringent guidelines.  相似文献   

10.
Patterns of epilithic diatom species distribution in relation to environmental variables from 12 sampling sites on the main stream and some of its tributaries in the Nilüfer Stream Basin were determined using multivariate statistical techniques. The stream basin has been heavily influenced by anthropogenic effects. The upper part of the basin that is distant from pollution sources mostly has a spring water quality, while the lower part where the stream flows through the urban area and receives domestic and industrial wastewater has a quite low quality. Ordination techniques using both diatom taxa and 21 environmental variables revealed non- to slightly polluted upper basin sites and highly polluted lower basin sites along the stream. The results showed that the stream catchment is polluted gradually from upstream to downstream and that most of the downstream sites have very low water quality especially in summer months. A total of 134 epilithic diatom taxa belonging to 50 genera were recorded for 12 sample sites. Partial CCA results indicated that water temperature (T), discharge (Q), and total phosphorus (TP) were the most important variables affecting the distribution of diatom species. Unpolluted or slightly polluted upper basin sites were dominated by Achnanthidium minutissimum, Cocconeis placentula var. euglypta, Gomphonema olivaceum, and Navicula tripunctata. Highly polluted lower basin sites were characterized by high levels of organic and inorganic matters and low dissolved oxygen (DO) values. Species widespread in the highly polluted lower basin sites such as Nitzschia umbonata, Nitzschia amphibia, Nitzschia capitellata, Nitzschia palea, Nitzschia paleacea, Luticola mutica, and Stephanodiscus niagarae were mostly related to pollution indicator variables such as ammonium nitrogen (NH4 +–N), sodium (Na+), total phosphorus (TP), and total organic matter (TOM).  相似文献   

11.
This study aimed to analyze the spectral trend of vegetation with rainfall in El Niño-Southern Oscillation events (ENSO) in the Atlantic Forest, Brazil. Monthly rainfall data were collected from 85 conventional meteorological stations (EMC), data from the Enhanced Vegetation Index 2 (EVI2) and ENSO events (El Niño, La Niña, and Neutral) in the period from 2001 to 2013. Afterwards, state cluster analysis was performed using the results of non-parametric tests. The Mann-Kendall (MK) non-parametric test did not identify a trend pattern in rainfall distribution in the Atlantic Forest. The results for EVI2 by state and region showed that the trend is decreasing in the Northeast Region, except for the states of Alagoas and Pernambuco. Southeast region showed an increasing trend of EVI2 (except for Rio de Janeiro and São Paulo), while the South region showed a decreasing trend. In the Midwest, the trend was significantly decreasing. In the prognosis elaborated for the future, the regions with significant declines of the vegetation were the Northeast and Midwest. This study shows that the Atlantic Forest in some regions of Brazil has been suffering from the growing urbanization process and there is a trend of soil degradation.  相似文献   

12.
Diarrhoea remains a global public health enigma raising deep concerns for the health planners since contaminated potable water often spoils the community health structure. We hereby report a 6-year odd continuing outbreak surveillance report based on potable water indices, during which 264 water samples were screened from different districts of West Bengal, India. Samples were analysed for the presence of different enteropathogenic bacterial species by conventional molecular tools and their sensitivity to antibiotics. 78.03% samples were positive for enteropathogenic bacterial organisms and 75% samples harbored Coliform. 45.45, 12.12, and 4.16% samples were positive for E.coli, V. cholerae, and V. mimicus, respectively. Diarrhoeagenic E.coli 7 EPEC, 10 ETEC, and 2 EIEC were isolated along with 2 V. cholerae O1 Ogawa (ctxA and tcpA ElTor positive), one each from tube well and pond. Interestingly, 4 V.cholerae non-O1/non-O139 also harbored hlyA gene. The detection of toxin genes among this bacterial pool of sampled water indicates the fallout of the potable water sources, thus enabling us to establish that it is none other than the contaminated potable water system which often wreaks havoc in the south Bengal diarrhoeal menace. The consequences are further complicated by the presence of drug-resistant pathogenic bacterial pool to fluoroquinolone, beta-lactams, and cephalosporins, in the accessible potable water, with threats of outbreaks exploding into an epidemic, given suitable environment, poor sanitation, and unhygienic practices. Therefore, we strongly recommend re-modelling of ‘point-of-use water disinfection’ measures and adequate personal hygiene for healthier community life.  相似文献   

13.
An optical method is developed to estimate water transparency (or underwater visibility) in terms of Secchi depth (Z sd ), which follows the remote sensing and contrast transmittance theory. The major factors governing the variation in Z sd , namely, turbidity and length attenuation coefficient (1/(c + K d ), c = beam attenuation coefficient; K d  = diffuse attenuation coefficient at 531 nm), are obtained based on band rationing techniques. It was found that the band ratio of remote sensing reflectance (expressed as (R rs (443) + R rs (490))/(R rs (555) + R rs (670)) contains essential information about the water column optical properties and thereby positively correlates to turbidity. The beam attenuation coefficient (c) at 531 nm is obtained by a linear relationship with turbidity. To derive the vertical diffuse attenuation coefficient (K d ) at 531 nm, K d (490) is estimated as a function of reflectance ratio (R rs (670)/R rs (490)), which provides the bio-optical link between chlorophyll concentration and K d (531). The present algorithm was applied to MODIS-Aqua images, and the results were evaluated by matchup comparisons between the remotely estimated Z sd and in situ Z sd in coastal waters off Point Calimere and its adjoining regions on the southeast coast of India. The results showed the pattern of increasing Z sd from shallow turbid waters to deep clear waters. The statistical evaluation of the results showed that the percent mean relative error between the MODIS-Aqua-derived Z sd and in situ Z sd values was within ±25%. A close agreement achieved in spatial contours of MODIS-Aqua-derived Z sd and in situ Z sd for the month of January 2014 and August 2013 promises the model capability to yield accurate estimates of Z sd in coastal, estuarine, and inland waters. The spatial contours have been included to provide the best data visualization of the measured, modeled (in situ), and satellite-derived Z sd products. The modeled and satellite-derived Z sd values were compared with measurement data which yielded RMSE = 0.079, MRE = ?0.016, and R 2  = 0.95 for the modeled Z sd and RMSE = 0.075, MRE = 0.020, and R 2  = 0.95 for the satellite-derived Z sd products.  相似文献   

14.
In the present study, organismic-level acute toxicology profile of three reactive azo dyes, viz. Reactive Blue 221, Reactive Red 195, and Reactive Yellow 145, was investigated, by using bacterial (Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, Listeria monocytogenes, and Bacillus subtilis), fungal (Trichoderma asperellum, Aspergillus flavus, Fusarium fujikuroi, and Rhizoctonia solani), plant (Raphanus sativus, Triticum aestivum, Sorghum bicolor, and Phaseolus mungo), and aquatic (Artemia salina and Daphnia magna) specimens. Microbial test organisms (all the six bacteria and two fungi, i.e., T. asperellum and A. flavus) and D. magna were found to be relatively more sensitive towards the reactive azo dyes and their mixture, as the EC50 values were in the range of 80–330, 135–360, and 108–242 ppm for bacteria, fungi, and D. magna, respectively (but the effect was not acutely toxic). Moreover, the effect of dye mixture was comparable tothe individual dyes in almost all the tested microbial specimens. For plant seeds, the dye mixture was found to be relatively more inhibitory towards T. aestivum and R. sativus than the individual dyes. For S. bicolor and P. mungo seeds, the effect of the dye mixture was almost identical to the individual dyes. However, in all cases, EC50 values were in the range of 950–3500 ppm, which indicates a non-toxic effect on plant seed germination potential. Likewise, the dyes and their mixture were not acutely toxic for Artemia salina larvae (more sensitive to the dye mixture) and Daphnia magna neonates (EC50, 516–950 and 108–242 ppm, respectively).  相似文献   

15.
Leachates from municipal solid wastes are liquids formed by organic and inorganic components suitable for biological treatment. In biological treatment plants, prediction of the output parameter value due to dynamic variation is essential. A dynamic model based on ASM1 has been applied for prediction of effluent COD value at real scale, using three different composition leachates. Tuning between dynamic variables and predicted parameter is tested for a correct proposal of the model. Dynamic model predicts correctly fluctuations in the output COD value and tempers dynamism caused by variation of temperature and biomass concentration in the case of high organic loaded leachates. Kinetic parameters Y H and K s are fixed to solve the model, and dynamic variables μ H and XBH are changing in time. μH,max is obtained in simulation (0.37–1.82 day?1) for minimum error between predicted values and experimental data. μH,max value is much lower compared with the value for domestic wastewater treatment due to lower biodegradability of leachate.  相似文献   

16.
In this study, an analysis was performed on the concentrations of the trace elements Al, As, Ba, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, V, and Zn in muscle of two carnivorous and one planktivorous fish species collected at Todos os Santos Bay (BTS). The accumulation order of the trace elements in Lutjanus analis was Al >Zn >Fe >Cr >Ba >Ni. In Cetengraulis edentulus, the order was Al >Fe >Zn >Cr >Ni >Mn >As. In the species Diapterus rhombeus, the order was Al >Fe >Zn >Cr >Ni >Mn >Cd. To determine the risk related to the consumption of fish, toxicity guidelines were used as standard references. It was observed that the species C. edentulus contained concentrations of As exceeding WHO limits, but these concentrations were acceptable according to the Agência Nacional de Vigilância Sanitária (ANVISA) guidelines. Cd levels were found only in D. rhombeus and in low concentrations according to the determinations of WHO and ANVISA. Pb levels were not detected in any of the three fish species. The analyzed elements did not differ statistically according to the species and feeding habits. The results point to possible risks of human contamination by As related to the consumption of the fish species C. edentulus from the BTS.  相似文献   

17.
Loss of green cover, and increasing pollution is a prime global concern. The problem calls for screening of pollution-tolerant tree species that can be integrated into plantation drives. Recognizing this, the study analyzed bio-indicator responses and performance of commonly occurring plant species along a pollution gradient in western Himalaya. Based on distance from the road, three sites viz., highly polluted (HP), moderately polluted (MP), and least polluted (LP), were identified. From these sites, leaves of commonly occurring 26 tree species were collected and analyzed for dust accumulation, total chlorophyll, relative water content (RWC), ascorbic acid, and pH using standard protocols. Later, assessment of Air Pollution Tolerance Index (APTI) and Anticipated Performance Indices (API) was carried out. The results revealed variations in biochemical characteristics. The pH, RWC, and total chlorophyll increased with decreasing pollution while ascorbic acid increased with increasing pollution. Dust capturing potential of Ficus carica (1.191 mg/m2) and Toona ciliata (0.820 mg/m2) was relatively higher. Based on the results of APTI, Grevillea robusta was classified as tolerant. It scored significantly higher values (21.06, 21.19, and 19.61 in LP, MP, and HP sites, respectively). Quercus floribunda, G. robusta (68.75% each), Juglans regia (68.7%), and T. ciliata (62.50%) were good performers in HP sites. Acer caesium, Betula utilis, and Morus alba that had low API scores (43.75%) were predicted as poor performers. Thus, G. robusta, Q. floribunda, J. regia, T. ciliata, and F. carica were evaluated as best performers. They could be integrated into plantations drives for environmental management.  相似文献   

18.
The aim of this study was to survey the response of the microbial community to crude oil and the diversity of alkane hydroxylase (alkB) genes in soil samples from the Qinghai-Tibet Plateau (QTP). The enrichment cultures and clone libraries were used. Finally, 53 isolates and 94 alkB sequences were obtained from 10 pristine soil samples after enrichment at 10 °C with crude oil as sole carbon source. The isolates fell into the phyla Proteobacteria, Actinobacteria, and Bacteroidetes, with the dominance of Pseudomonas and Acinetobacter. The composition of degraders was different from polar habitats where Acinetobacter sp. is not a predominant responder of alkane degradative microbial communities. Phylogenetic analysis showed that the alkB genes from isolates and enrichment communities formed eight clusters and mainly related with alkB genes of Pseudomonas, Rhodococcus, and Acinetobacter. The alkB gene diversity in the QTP was lower than marine environments and polar soil samples. In particular, a total of 10 isolates exhibiting vigorous growth with crude oil could detect no crude oil degradation-related gene sequences, such as alkB, P450, almA, ndoB, and xylE genes. The Shannon-Wiener index of the alkB clone libraries from the QTP ranged from 1.00 to 2.24 which is similar with polar pristine soil samples but lower than that of contaminated soils. These results indicated that the Pseudomonas, Acinetobacter, and Rhodococcus genera are the candidate for in situ bioremediation, and the environment of QTP may be still relatively uncontaminated by crude oil.  相似文献   

19.
Biochemical constituents and master elements (Pb, Cr, Cd, Fe, Cu, Zn, Hg, B, Al, SO4 2?, Na, K, Li, Ca, Mg, and F) were investigated in six different seaweed species from Abu Qir Bay in the Egyptian Mediterranean Sea coast. The moisture level ranged from 30.26% in Corallina mediterranea to 77.57% in Padina boryana. On dry weight basis, the ash contents varied from 25.53% in Jania rubens to 88.84% in Sargassum wightii. The protein contents fluctuated from 8.26% in S. wightii to 28.01% in J. rubens. Enteromorpha linza showed the highest lipids (4.66%) and carbohydrate contents (78.95%), whereas C. mediterranea had the lowest lipid (0.5%), and carbohydrate contents (38.12%). Chlorophylls and carotenoid contents varied among the species. Total antioxidant capacity of the tested green seaweeds had the highest activities followed by brown and red seaweeds which had a similar trend of phenol and tannins contents. High reducing power was observed in all tested seaweeds extract except Ulva lactuca. Brown species had the highest amount of elements followed by red and green seaweeds. Notably, SO4 2? recorded the highest level in the tested green species (108.05 mg/g dry weight (DW)). The Ca/Mg and K/Na ratios reflected highly significant difference between seaweed species. This study keeps an eye on 29 parameters and by applying stepwise multiple regression analysis, prospective equations have been set to describe the interactions between these parameters inside seaweeds. Accordingly, the tested seaweeds can be recommended as a source of healthy food with suitable ion quotient and estimated daily intake values.  相似文献   

20.
Seasonal and spatial phytoplankton distribution in relation to environmental factors was investigated in New Mangalore Port, a major port along the west coast of India. A well-mixed water column characterized the non-monsoon seasons, whereas it was weakly stratified during monsoon. Water quality index (TRIX) scores indicated good water quality except during pre-monsoon (inner zone surface) and monsoon (near bottom waters). Surface abundance of tychopelagic diatoms (Paralia sulcata, Melosira nummuloides, Cylindrotheca closterium, and Nitzschia sigma) was higher during non-monsoon seasons. Certain centric diatoms, e.g., Leptocylindrus danicus, P. sulcata, and Rhizosolenia imbricata, dominated during pre-monsoon (inner zone) and positively correlated with TRIX. High Skeletonema costatum and dinoflagellate abundance during the monsoon season coincided with high nutrient concentrations. Five potential toxic and fourteen harmful/bloom forming algal species were encountered at abundances below the level that can be considered as harmful to the ecosystem. In addition to a baseline database, this study highlights the potential use of certain diatom species as indicators of hydrography and water quality for monitoring dynamic coastal marine ecosystems.  相似文献   

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