Displaying publications 1 - 20 of 969 in total

  1. Kuznetsov AN, Kuznetsova SP
    Izv. Akad. Nauk. Ser. Biol., 2013 Mar-Apr;?(2):206-16.
    PMID: 23789426
    This study was carried out during the period 1989-2011. The following areas were included: Vietnam, Laos, Cambodia, Indonesia, and Malaysia. Climax tropical forest and anthropogenically transformed ecosystems, including those damaged by the chemical warfare program of the United States in Vietnam, were investigated. Some regularities in the structure dynamics and functioning of forests ecosystems under a tropical monsoon climate have been revealed. The principles of classification of tropical forests have been elaborated. The major results of investigation of the tropical monsoon forests in Vietnam are given.
    Matched MeSH terms: Ecosystem*
  2. Ryss AIu
    Parazitologia, 2007 Mar-Jun;41(3):161-94.
    PMID: 17722638
    The amended diagnosis of the genus Pratylenchoides and list of its valid species with synonyms are given. All the efficient diagnostic characters are listed. Modern taxonomic standard for the description of Pratylenchoides species is proposed; it may be used also in taxonomic databases. Tabular and text keys for all species of the genus are given. Five following groups are considered within the genus Pratylenchoides. The group arenicola differs from other groups in the primitive adanal bursa type; the groups magnicauda, crenicauda, ritteri, and megalobatus differ from each other in the position of cardium along the body axis in relation to the pharyngeal gland nuclei, pharynx types are named according to the stages of its evolution from the primitive tylenchoid pharynx (cardium situated posteriorly) to the advanced hoplolaimoid one (cardium situated anteriorly). Diagnoses and species compositions of the groups are given. Basing on the matrix of species characters, the dendrogram has been generated for all species of Pratylenchoides and for all characters (UPGMA, distance, mean character difference, random, characters ordered). Taking in view that the PAUP software gives equal weights to all characters, including the most important ones which define the prognostic species groups, the separate dendrograms for each prognostic species group were generated using the same above mentioned tree parameters. On the base of the records of Pratylenchoides species the matrices of plant host ranges, geographic distribution, and preferred soil-climatic conditions were developed. The dendrograms of the faunal similarities were generated using these matrices, with conclusions on a possible origin and evolution of the genus. The genus evolved from the flood lands with swampy soils and prevalence of dicotyledons (herbaceous Lamiaceae and woody Salicaceae families) to the forest mainland communities with balanced humidity and predominance of herbaceous Poaceae and Fabaceae with woody Fagaceae, Betulaceae, and Oleaceae. The leading factor of the evolutional adaptation to soil-climatic conditions was the factor of humidity, but its significance gradually decreased with the host change to more advanced plant taxa adapted to the communities with more dry balanced humidity. The genus took its origin on the south shores of Laurasia in the Cainozoe. Later, when Hindistant and Arabian Peninsula joined with Laurasia creating the Himalayas barrier, the Pratylenchoides spp. distributed by two branches: the northern one moved into Central Asia, East Europe and North America, and the south branch came into Indo-Malaya, West Asia and the north of Africa. The remnants of the ancient species groups remain in West Europe and East Asia. In the North America the genus gave an origin to its sister genus Apratylenchoides, which spread to the south up to Antarctica; another advanced branch spread in the North America reaching Alaska.
    Matched MeSH terms: Ecosystem
  3. Beaucournu JC, Wells K
    Parasite, 2009 Dec;16(4):283-7.
    PMID: 20092059
    We report on fleas collected from small mammals in a lower mountane rainforest in the Crocker Range National Park, Sabah, Borneo. Macrostylophora durdeni n. sp., collected from Dremomys everetti and, of minor importance, Tupaia montana, is described. Further records include Gryphopsylla jacobsoni segragata and Lentistivalius vomerus from T. montana.
    Matched MeSH terms: Ecosystem
  4. Sing, Lui Lo, Chen, Cheng Ann, Tzuen, Kiat Yap, Teruaki Yoshida
    A comparison of zooplankton abundance and community in the seagrass and non-seagrass areas of Limau-limauan and Bak- Bak waters within the newly established Tun Mustapha Marine Park was made during 15-17 May 2017. Samples were collected via horizontal tow of a 140 μm plankton net. Environmental variables (temperature, salinity, DO, pH, turbidity) showed no significant differences among the study sites. However, zooplankton showed increasing abundance from non-seagrass, seagrass edge, to seagrass areas at Limau-limauan, while abundance values were comparable among the stations at Bak-bak. Overall zooplankton abundance was significantly higher at the seagrass areas relative to the non-seagrass station at Limau-limauan (p < 0.005), while no statistical difference was found at Bak-Bak (p < 0.21). Mean canopy height was 3-fold higher (p < 0.001) at Limau-limauan than Bak-Bak, suggesting the importance of seagrass bed structural complexity in habitat preference for zooplankton. Cluster analysis revealed the zooplankton community from the seagrass area at Limau-limauan was different from that at seagrass edge and non-seagrass areas, which may be attributed to the influence of seagrass meadows in forming characteristic zooplankton compositions. Marked differences in zooplankton composition and abundance even in close vicinity of sites suggest the importance of local small-scale variations in seagrass habitats in shaping the zooplankton community.
    Matched MeSH terms: Ecosystem
  5. Hassnah Wee, Nur Nadirah Abdul Wahab, Zamhariyah Ahmad Fudil
    Jurnal Inovasi Malaysia, 2020;4(1):151-171.
    Tourists visiting destination in warm climate countries such as Malaysia might easily be affected with dehydration problem. Places like the Zoo requires tourist to walk intensively inside the Zoo area may cause dehydration if they do not consume enough plain water. This ZIBMAP innovative product intends to benefit the tourist wellness who visits the National Zoo, comes with an informative map and attractive infographic habitat, which can be kept as a souvenir. This innovative product is designed based on environmental-friendly features that support the implementation of environmental sustainability. A feasibility survey on dehydration risk awareness and the potential of the product acceptance for commercialization was carried out using a quantitative method. A convenience sampling technique was used to identify 300 tourists visiting the National Zoo as respondents for this survey. Descriptive analysis results indicated that majority of respondents aware of the dehydration risk and supported the used of the ZIBMAP innovative product. The outcome of the study highlighted the potential of this product to be commercialized and contribute to tourists’ wellness.
    Matched MeSH terms: Ecosystem
  6. Shahul Hamid F, Bhatti MS, Anuar N, Anuar N, Mohan P, Periathamby A
    Waste Manag Res, 2018 Oct;36(10):873-897.
    PMID: 30103651 DOI: 10.1177/0734242X18785730
    The widespread occurrence of microplastic has invaded the environment to an extent that it appears to be present throughout the globe. This review investigated the global abundance and distribution of microplastics in marine and freshwater ecosystems. Furthermore, the issues and challenges have been addressed for better findings in microplastics studies. Findings revealed that the accumulation of microplastics varies geographically, with locations, hydrodynamic conditions, environmental pressure, and time. From this review, it is crucial that proper regulations are proposed and implemented in order to reduce the occurrence of microplastics in the aquatic environment. Without appropriate law and regulations, microplastic pollution will eventually threaten human livelihood.
    Matched MeSH terms: Ecosystem
  7. Evenhuis NL
    Zootaxa, 2016 Nov 10;4189(2):zootaxa.4189.2.1.
    PMID: 27988730 DOI: 10.11646/zootaxa.4189.2.1
    The Strongylophthalmyia punctata subgroup, comprising 24 species with armored fore femora, and restricted primarily to SE Asia, is reviewed. Eighteen new species, S. albisternum, n. sp. (Thailand), S. borneensis, n. sp. (Borneo), S. caestus, n. sp. (Philippines), S. darlingi, n. sp. (Sumatra), S. federeri, n. sp. (Philippines), S. hauseri, n. sp. (Thailand, Vietnam), S. indochinensis, n. sp. (Cambodia, Thailand, Vietnam), S. inundans, n. sp. (Philippines), S. laosensis, n. sp. (Laos), S. lowi, n. sp. (Peninsular Malaysia), S. malayensis, n. sp. (Peninsular Malaysia), S. nigripalpis, n. sp. (Peninsular Malaysia), S. oxybeles, n. sp. (Sumatra), S. pappi, n. sp. (Thailand), S. phillindablank, n. sp. (China), S. sichuanica, n. sp. (China), S. sumatrana, n. sp. (Sumatra), and S. thailandica, n. sp. (Thailand) are described and illustrated, S. microstyla Shatalkin and S. punctata Hennig are redescribed based on examination of the holotypes, and a key to species of the subgroup is presented. A general taxonomic overview of the genus Strongylophthalmyia is given with discussion of and keys to proposed species groups.
    Matched MeSH terms: Ecosystem
  8. Luskin MS, Johnson DJ, Ickes K, Yao TL, Davies SJ
    Proc Biol Sci, 2021 03 10;288(1946):20210001.
    PMID: 33653133 DOI: 10.1098/rspb.2021.0001
    Large vertebrates are rarely considered important drivers of conspecific negative density-dependent mortality (CNDD) in plants because they are generalist consumers. However, disturbances like trampling and nesting also cause plant mortality, and their impact on plant diversity depends on the spatial overlap between wildlife habitat preferences and plant species composition. We studied the impact of native wildlife on a hyperdiverse tree community in Malaysia. Pigs (Sus scrofa) are abnormally abundant at the site due to food subsidies in nearby farmland and they construct birthing nests using hundreds of tree saplings. We tagged 34 950 tree saplings in a 25 ha plot during an initial census and assessed the source mortality by recovering tree tags from pig nests (n = 1672 pig-induced deaths). At the stand scale, pigs nested in flat dry habitats, and at the local neighbourhood scale, they nested within clumps of saplings, both of which are intuitive for safe and efficient nest building. At the stand scale, flat dry habitats contained higher sapling densities and higher proportions of common species, so pig nesting increased the weighted average species evenness across habitats. At the neighbourhood scale, pig-induced sapling mortality was associated with higher heterospecific and especially conspecific sapling densities. Tree species have clumped distributions due to dispersal limitation and habitat filtering, so pig disturbances in sapling clumps indirectly caused CNDD. As a result, Pielou species evenness in 400 m2 quadrats increased 105% more in areas with pig-induced deaths than areas without disturbances. Wildlife induced CNDD and this supported tree species evenness, but they also drove a 62% decline in sapling densities from 1996 to 2010, which is unsustainable. We suspect pig nesting is an important feature shaping tree composition throughout the region.
    Matched MeSH terms: Ecosystem
  9. Fujinuma J, Harrison RD
    PLoS One, 2012;7(5):e37321.
    PMID: 22615977 DOI: 10.1371/journal.pone.0037321
    Edge-effects greatly extend the area of tropical forests degraded through human activities. At Pasoh, Peninsular Malaysia, it has been suggested that soil disturbance by highly abundant wild pigs (Sus scrofa), which feed in adjacent Oil Palm plantations, may have mediated the invasion of Clidemia hirta (Melastomataceae) into the diverse tropical lowland rain forest. To investigate this hypothesis, we established three 1 km transects from the forest/Oil Palm plantation boundary into the forest interior. We recorded the distribution of soil disturbance by wild pigs, C. hirta abundance, and environmental variables. These data were analyzed using a hierarchical Bayesian model that incorporated spatial auto-correlation in the environmental variables. As predicted, soil disturbance by wild pigs declined with distance from forest edge and C. hirta abundance was correlated with the level of soil disturbance. Importantly there was no effect of distance on C. hirta abundance, after controlling for the effect of soil disturbance. Clidemia hirta abundance was also correlated with the presence of canopy openings, but there was no significant association between the occurrence of canopy openings and distance from the edge. Increased levels of soil disturbance and C. hirta abundance were still detectable approximately 1 km from the edge, demonstrating the potential for exceptionally large-scale animal mediated edge effects.
    Matched MeSH terms: Ecosystem*
  10. Fayle TM, Turner EC, Basset Y, Ewers RM, Reynolds G, Novotny V
    Trends Ecol Evol, 2015 Jun;30(6):334-46.
    PMID: 25896491 DOI: 10.1016/j.tree.2015.03.010
    Tropical forests are highly diverse systems involving extraordinary numbers of interactions between species, with each species responding in a different way to the abiotic environment. Understanding how these systems function and predicting how they respond to anthropogenic global change is extremely challenging. We argue for the necessity of 'whole-ecosystem' experimental manipulations, in which the entire ecosystem is targeted, either to reveal the functioning of the system in its natural state or to understand responses to anthropogenic impacts. We survey the current range of whole-ecosystem manipulations, which include those targeting weather and climate, nutrients, biotic interactions, human impacts, and habitat restoration. Finally we describe the unique challenges and opportunities presented by such projects and suggest directions for future experiments.
    Matched MeSH terms: Ecosystem*
  11. Jani J, Lusk MG, Yang YY, Toor GS
    PLoS One, 2020;15(4):e0230908.
    PMID: 32236119 DOI: 10.1371/journal.pone.0230908
    Stormwater runoff is recognized as a cause of water quality degradation because it may carry nitrogen (N) and other pollutants to aquatic ecosystems. Stormwater ponds are a stormwater control measure often used to manage stormwater runoff by holding a permanent pool of water, which reduces the peak flow, magnitude of runoff volume, and concentrations of nutrients and pollutants. We instrumented the outlet of a stormwater pond in an urban residential neighbourhood in Florida, United States to (1) investigate the concentration and composition of N forms during the summer rainy season (May to September 2016), and (2) determine the bioavailability of organic N in the stormwater pond with a bioassay experiment. A total of 144 outflow water samples over 13 storm events were collected at the outlet of the stormwater pond that collects runoff from the residential catchment. Samples were analysed for various inorganic N [ammonium (NH4-N), nitrate (NO3-N)], and organic N forms [dissolved organic nitrogen (DON), and particulate organic nitrogen (PON)]. Flow-weighted mean concentration of total N (TN) in pond outflow for all collected storm events was 1.3±1.42 mg L-1, with DON as the dominant form (78%), followed by PON and NO3-N (each at 8%), and NH4-N (6%). In the bioassay experiment, organic N (DON+PON) was significantly decreased by 25-28% after 5 days of incubation, suggesting that a portion of the DON carried from the pond outflow to receiving water bodies may be bioavailable. These results suggest that efforts to mitigate stormwater N outflows from urban ponds should incorporate both inorganic and organic N in management plans.
    Matched MeSH terms: Ecosystem
  12. Zulkafli Abdul Rashid, Mohammad Noor Azmai Amal
    Sains Malaysiana, 2018;47:1941-1951.
    This study assesses the influence of water quality on fish occurrences in Sungai Pahang, Maran District, Pahang, Malaysia. Water quality and fish samplings were conducted at seven sampling sites in the district for 13 consecutive months. We used canonical correspondence analyses (CCA) to determine the influence of water quality on monthly fish species occurrences. The ranges of water quality parameters were quite high considering the measurements were made during rainy and dry seasons throughout the year. A total of 2,075 individual fish was captured which comprised of 22 different families and 65 species. Family Cyprinidae recorded the highest number of fish species of the area (27 species; 41.5%), followed by Bagridae (five species; 7.69%) and Pangasiidae (five species; 7.69%). Three fish species categorized as endangered, including Balantiocheilos melanopterus, Probarbus jullieni and Pangasianodon hypophthalmus were also collected. The collected fish species were divided into three groups (A to C), which was clearly separated in the CCA ordination diagram. The most important water quality variables for the fish occurrences in this river were pH, followed by temperature, conductivity, alkalinity and phosphate. Data analysis indicates that the occurrence of fishes were influenced by a combination of water quality parameters, but not associated with sampling month. The results present a new data from a study of fish assemblage and their habitat condition which may be important in fisheries activity and fish conservation of the river in the future.
    Matched MeSH terms: Ecosystem
  13. Hussein Aliu Sule, Ahmad Ismail, Mohammad Noor Azmai Amal, Syaizwan Zahmir Zulkifli, Mohd Fauzul Aidil Mohd Roseli, Shamarina Shohaimi
    Sains Malaysiana, 2018;47:2589-2600.
    Tropical peat swamp forest (PSF) is one of the most endangered ecosystems in the world. However, the impacts of
    anthropogenic activities in PSF and its conversion area towards fish biodiversity are less understood. This study
    investigates the influences of water physico-chemical parameters on fish occurrences in peat swamp, paddy field and
    oil palm plantation in the North Selangor peat swamp forest (NSPSF), Selangor, Malaysia. Fish and water samples were
    collected from four sites located in the peat swamps, while two sites were located in the paddy field and oil palm plantation
    areas. Multivariate analyses were used to determine the associations between water qualities and fish occurrences in
    the three habitats. A total of 1,382 individual fish, belonging to 10 families, 15 genera and 20 species were collected.
    The family Cyprinidae had the highest representatives, followed by Bagridae and Osphronemidae. The most abundant
    species was Barbonymus schwanefeldii (Bleeker 1854), while the least abundant was Wallago leerii Bleeker, 1851. The
    paddy field and oil palm plantation area recorded significantly higher fish diversity and richness relative to peat swamp
    (p<0.05). The water physico-chemical parameters, such as pH, DO, NH3
    -N, PO4, SO4
    , and Cl2 showed no significant
    difference between paddy field and oil palm plantation (p>0.05), but was significantly different from the peat swamp
    (p<0.05). However, no water quality parameter was consistently observed to be associated with fish occurrences in all
    of the three habitats, but water temperature, NH3
    -N, Cl2, SO4
    , and EC were at least associated with fish occurrences in
    two habitats studied. This study confirmed that each habitat possess different water quality parameters associated with
    fish occurrences. Understanding all these ecological aspects could help future management and conservation of NSPSF.
    Matched MeSH terms: Ecosystem
  14. Ayub KR, Zakaria NA, Abdullah R, Ramli R
    Water Sci Technol, 2010;62(8):1931-6.
    PMID: 20962410 DOI: 10.2166/wst.2010.473
    The Bio-ecological Drainage System, or BIOECODS, is an urban drainage system located at the Engineering Campus, Universiti Sains Malaysia. It consists of a constructed wetland as a part of the urban drainage system to carry storm water in a closed system. In this closed system, the constructed wetland was designed particularly for further treatment of storm water. For the purpose of studying the water balance of the constructed wetland, data collection was carried out for two years (2007 and 2009). The results show that the constructed wetland has a consistent volume of water storage compared to the outflow for both years with correlation coefficients (R(2)) of 0.99 in 2007 and 0.86 in 2009.
    Matched MeSH terms: Ecosystem*
  15. Thanapackiam P, Salleh KO, Ghaffar FA
    J Environ Biol, 2012 Apr;33(2 Suppl):373-9.
    PMID: 23424840
    This paper discusses the outcome of a research that examines the relationships between vulnerability and adaptation of urban dwellers to the slope failure threat in the Klang Valley Region. Intense urban landuse expansions in the Klang Valley Region have increased urban dwellers vulnerability to slope failures in recent years. The Klang Valley Region was chosen as the study area due to the increasing intensities and frequencies of slope failures threat. This paper examines urban dwellers vulnerability based on their (1) population and demographics characteristics, (2) the state of physical structures of dwellings and (3) the situation of the immediate environment threatened by slope failures. The locations of slope failure incidents were identified, mapped and examined followed with a detailed field study to identified areas. The results identified significant relationships between vulnerability indicators and slope failures in the Klang Valley Region. The findings of the study are envisaged to give valuable insights on addressing the threat of slope failures in the Klang Valley Region.
    Matched MeSH terms: Ecosystem
  16. Saaban S, Yasak MN, Gumal M, Oziar A, Cheong F, Shaari Z, et al.
    PeerJ, 2020;8:e8209.
    PMID: 32002318 DOI: 10.7717/peerj.8209
    The need for conservation scientists to produce research of greater relevance to practitioners is now increasingly recognized. This study provides an example of scientists working alongside practitioners and policy makers to address a question of immediate relevance to elephant conservation in Malaysia and using the results to inform wildlife management policy and practice including the National Elephant Conservation Action Plan for Peninsular Malaysia. Since ensuring effective conservation of elephants in the Endau Rompin Landscape (ERL) in Peninsular Malaysia is difficult without data on population parameters we (1) conducted a survey to assess the size of the elephant population, (2) used that information to assess the viability of the population under different management scenarios including translocation of elephants out of the ERL (a technique long used in Malaysia to mitigate human-elephant conflict (HEC)), and (3) assessed a number of options for managing the elephant population and HEC in the future. Our dung-count based survey in the ERL produced an estimate of 135 (95% CI [80-225]) elephants in the 2,500 km2 area. The population is thus of national significance, containing possibly the second largest elephant population in Peninsular Malaysia, and with effective management elephant numbers could probably double. We used the data from our survey plus other sources to conduct a population viability analysis to assess relative extinction risk under different management scenarios. Our results demonstrate that the population cannot sustain even very low levels of removal for translocation or anything other than occasional poaching. We describe, therefore, an alternative approach, informed by this analysis, which focuses on in situ management and non-translocation-based methods for preventing or mitigating HEC. The recommended approach includes an increase in law enforcement to protect the elephants and their habitat, maintenance of habitat connectivity between the ERL and other elephant habitat, and a new focus on adaptive management.
    Matched MeSH terms: Ecosystem
  17. Wan-Norafikah O, Nazni WA, Noramiza S, Shafa'ar-Ko'ohar S, Azirol-Hisham A, Nor-Hafizah R, et al.
    Trop Biomed, 2010 Dec;27(3):662-7.
    PMID: 21399609
    A preliminary study on the vertical dispersal of Aedes populations in high-rise apartments was carried out in Presint 9, Putrajaya, Malaysia. Ovitraps were placed indoors within four blocks of high-rise apartments from the ground floors (0.0 - 3.0 m) until up to the tenth floors (28.1 - 30.0 m). Aedes aegypti was the dominant species found in the ovitraps (87.85%), while Aedes albopictus was found in lower numbers. From total number of larvae collected (650), 40.92% of these larvae were obtained from the fourth block; Block D. The peak density of Aedes sp. was observed at level 6 (16.1 - 18.0 m), while Ae. aegypti was found until the tenth floor (28.1 - 30.0 m). In contrast, Ae. albopictus was found only up to the sixth floor (16.1 - 18.0 m). A poor correlation of the mean number of Aedes larvae collected with the level of high-rise apartments occupied (N=40; ρ=-0.349) was also observed which indicated the possibility of lesser Aedes populations to be found at higher level of high-rise apartments. Therefore, larger scale studies are strongly recommended to examine the vertical dispersal of Aedes mosquitoes.
    Matched MeSH terms: Ecosystem*
  18. Hawkes FM, Manin BO, Cooper A, Daim S, R H, Jelip J, et al.
    Sci Rep, 2019 09 16;9(1):13312.
    PMID: 31527622 DOI: 10.1038/s41598-019-49842-2
    In lowland areas of Malaysia, Plasmodium knowlesi infection is associated with land use change and high proportions of the vector Anopheles balabacensis. We conducted a 15-month study in two Malaysian villages to determine the effect of habitat on vector populations in understudied high-altitude, high-incidence districts. Anopheles mosquitoes were sampled in human settlements, plantations and forest edges, and screened for Plasmodium species by PCR. We report the first An. donaldi positive for P. knowlesi. This potential vector was associated with habitat fragmentation measured as disturbed forest edge:area ratio, while An. balabacensis was not, indicating fragmented land use could favour An. donaldi. Anopheline species richness and diversity decreased from forest edge, to plantation, to human settlement. Greater numbers of An. balabacensis and An. donaldi were found in forest edges compared to human settlements, suggesting exposure to vectors and associated zoonoses may be greater for people entering this habitat.
    Matched MeSH terms: Ecosystem
  19. Arai T, Chino N
    J Fish Biol, 2019 May;94(5):752-758.
    PMID: 30847927 DOI: 10.1111/jfb.13952
    Fish movements between aquatic habitats of different salinity ranges (fresh, estuarine, marine) by the tropical catadromous eels Anguilla bicolor bicolor and A. bicolor pacifica were examined by analysing the otolith strontium and calcium concentrations of yellow (immature) and silver (mature) stage eels collected in south-east Asian (Indonesia, Malaysia and Vietnam) waters. The ratios suggest that all migratory-type eels, including freshwater, brackish water and marine residents, pass the river mouth. However, the habitat preference was different among the sites (countries). In Indonesia and Vietnam, most A. bicolor bicolor and A. bicolor pacifica were either marine or brackish water residents in this study. Alternatively, most A. bicolor bicolor were freshwater residents in Malaysia; such a typical catadromous migration pattern in these eels has not been found in previous studies. The wide range of otolith Sr:Ca in both subspecies indicates that the habitat use of these tropical eels was opportunistic among fresh, brackish and marine waters during their growth phases following recruitment to coastal areas. The geographical variability of migratory histories suggests that habitat use might be determined by the inter and intraspecific competition and environmental conditions at each site.
    Matched MeSH terms: Ecosystem*
  20. Saravi HN, Din ZB, Makhlough A
    Pak J Biol Sci, 2008 May 01;11(9):1179-93.
    PMID: 18819525
    Temporal variations and regional distributions of dissolved nutrients and their elemental ratios in the Iranian coastal waters of the Southern Caspian Sea were investigated. The data were collected in 1996-97 (Phase I, as a background data and undisturbed ecosystem) and in 2005 (Phase II, as a disturbed ecosystem) at sampling points (from 10 to 100 m depths). In addition to the two main sampling exercises, additional sample collections were carried out during the period of 1994 to 2004 as a long-term study. This study showed that the dissolved inorganic nitrogen/dissolved inorganic phosphorus (DIN/DIP) ratios in the southern Caspian Sea vary within a very narrow range (4.47 to 5.78) within the euphotic and aphotic layers and is by one order of magnitude lower than what have been reported for several other marine ecosystems. Phytoplankton growth seems to be nitrogen limited while the levels of P and Si always remain high. Factor Analysis/Principal Component Analysis (FA/PCA) of the correlation matrix showed that the nitrogen compounds are associated with the main factor accounting for 25.7-26.2% of the total variance for both the sampling periods. During Phase I, the Chrysophyta were the major group, whereas during Phase II the proportion of Chrysophyta in the total community progressively decreased, while the other groups increased.
    Matched MeSH terms: Ecosystem
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links