Tidal Influence On The Physico-Chemical Parameters, Temporal and Spatial Distribution Of Zooplankton in Langat River-Estuarine Area, Malaysia

The objectives of present study were to study the water quality, zooplankton distribution and its community structure along a salinity gradient in Langat river estuarine system (20 46'N, 1010 26' E), during low and high tides. Five sampling stations from the coastal area to the upstream were chosen for this study. Station 1 was in the coastal area while Station 5 was at the most upstream, the rest of the Stations (Stations 2,3 and 4) are located in between, passing along the river gradient. Zooplankton and water samples were collected and analyzed monthly for a period of 12 months (January to December 2003). The water quality, nutrients and zooplankton distribution changed according to the stations and tides. The mean salinity ranged from 32.94k1.20 PSU in coastal waters to 27.78k1.21 PSU in upstream station during high tide. During low tide, the mean salinity in the most upstream station was as low as 1.00k0.90 PSU. Higher Dissolved Oxygen values ranged (means of 5.84k0.35 to 7.09k0.13 mgL-1) during high tide and it decreased (means of 3.91k0.71 to 5.22k0.71 mgL-1) during low tide. On the other hand, the nutrients such as total ammonia nitrogen (ranged from 0.0014k0.001 mgL-1 to 2.5714k0.980 mgL-I), nitrite+nitrate-nitrogen (ranged from 0.0021k0.001 mgL-1 to 0.8100k0.211 mgL-1) and total phosphorus (ranged from 0.0712k0.024 mgL-1 to O.867Ok 0.3241 mgL-l) showed increasing trend from the coastal areas to the upstream. The highest chlorophyll a was recorded at Station 3 with mean values of 10.27k0.84 pgL-I and 3.94k1.06 pgL-1 during high and low tide, respectively. The mean zooplankton density was lowest in the coastal areas (16.21 x 103 k4679.07 individuals m-3) and highest in Station 4 with a mean value 119.81 x 103k43338.73 individuals m-3 during high tide. Copepods dominated zooplankton populations contributing >80% in all the stations throughout the sampling period. The other zooplankton groups such as cnidarians, appendicularians, polychaetes, ostracods, chaetognaths and shrimp larva were distributed in coastal estuarine areas whereas echinoderm larvae were restricted to coastal waters and cladocerans were found only at the upstream stations (Stations 3-5).This study recorded 50 species of copepods which was dominated by the calanoids, Acartia spinicauda, A. amboinensis and A. erythraea accounting for 28%, 18% and 11% of the total copepod populations, respectively. High species diversity occurred in Station 1 decreasing towards the upstream. Species diversity varied depending on the tides, being higher during high tides and than low tides. Some copepod species were highly restricted to the high salinity levels (>30 PSU) while some species could tolerate wide range of salinity from 5 - >30 PSU. Major stenohaline species was Oithona simplex and major euryhaline species were Acartia spinicauda, A. amboinensis and A. erythraea. Zooplankton biomass study showed the highest in station 3 (dry weight 6l2.3Of 26.31 mg m-3 high tide) and lowest in Station 2 (150.051t 54.71 mg m-3 during low tide). This study showed that water quality, nutrient concentrations and the distribution of zooplankton varied according to tides, where high tides resulted in better water quality, higher zooplankton density and higher species diversity compared to low tides. On the other hand, water quality was better and species diversity higher in coastal areas compared to other stations throughout the sampling period regardless of tides

Comparative Phyto and Physicochemical Parameters of the Therapeutic Plant Syzygium cumini (L.) Skeels in Jaffna District

Syzygium cumini (L.) Skeels (Myrtaceae) is an evergreen tree, grown widely in Sri Lanka. It is regularly recognized as jambolan, black plum, and jamun. It is an extensively used therapeutic herbal in the treatment of innumerable illnesses, particularly in Diabetes mellitus in traditional medicine. The goal of the research was to compare the phytochemical and physicochemical properties between the different parts of jambolana tree which is naturally found in Sri Lanka. Proximate estimation of physicochemical properties of dried matured different parts as bark, leaves, fruits, and seeds of the Syzygium cumini havebeen done in the current study rendering to the standard protocols recommended by the World Health Organization (WHO) and Association of Analytical Chemist (AOAC). This study includes electrical conductivity value, moisture content, fat content, and different ash contents analysis. It was found that the leaves had the highest electrical conductivity (16.67±1.53) and the bark had the lowest electrical conductivity (2.44±0.03). The moisture content of the bark was lower (11.30±0.44) in comparison tothat of the seeds (16.34±0.43). Furthermore, the bark had the highest fat content (1.02±0.03) and acid insoluble ash (2.65±0.89), when compared to the seeds (0.65±0.01) and leaves (1.00±0.88) respectively. The seeds had the highest pH (5.39±0.08); total ash (2.18±0.06) and water-soluble ash (5.25±0.55), while the fruits had the highest sulphated ash (1.99±0.55). Qualitative inspection revealed that hot ethanolic seed extracts contained high levels of flavonoids, tannins, phenols, glycosides, alkaloids, terpenoids and quinones, in addition to other parts, which also had high levels of alkaloid content (81.06 mg/g). The current study will contribute useful data in the precise documentation and validation of various parts of S. cumini and may aid in removing contaminants in the preparation of nutraceuticals or medicine. Keywords: Medicinal Plant, Parts, Parameters, Physicochemical, Phytochemical, Syzygium cumin

An Efficient, Modular Approach for the Synthesis of (+)-Strictifolione and a Related Natural Product

An efficient, library amenable, “pot economical” total synthesis of (+)-strictifolione and the related natural product, (6R)-6[(E,4R,6R)-4,6-dihydroxy-10-phenyl-1-decenyl]-5,6-dihydro-2H-2-pyrone are reported. This modular approach takes advantage of two consecutive phosphate tether-mediated, one-pot, sequential protocols, followed by a final cross metathesis to deliver both antifungal natural products in a three-pot process from the respective enantiomeric (R,R)- and (S,S)-trienes with minimal purification. A salient feature of this route is that additional protecting groups are not required as a result of the orthogonal protecting- and leaving-group properties innate to phosphate triesters

Remote sensing and hydrologic models for performance assessment in Sirsa Irrigation Circle, India

Irrigation management / Irrigation systems / Irrigation canals / Performance evaluation / Remote sensing / GIS / Models / Irrigated farming / Hydrology / Satellite surveys / Irrigation scheduling / Evapotranspiration / India

The effect of universal maternal antenatal iron supplementation on neurodevelopment in offspring : a systematic review and meta-analysis

Funding One author (CJ) was funded by the Ministry of Health, Government of Sri Lanka. Availability of data and materials Supporting data can be obtained from the corresponding author.Peer reviewedPublisher PD

Salivary Interleukin Levels in Oral Squamous Cell Carcinoma and Oral Epithelial Dysplasia : Findings from a Sri Lankan Study

Acknowledgments The authors would like to thank the laboratory staff at the Department of Microbiology, Faculty of Medical Sciences, University of Sri Jayewardenepura, Gangodawila, Nugegoda, Sri Lanka. The authors would like to thank Thilini Nisansala and Chamikara Liyanage for their help in the laboratory analysis. Funding N.S.P. was financially supported by the Elphinstone Scholarship, University of Aberdeen, UK and the University Grants Commission, Sri Lanka.Peer reviewedPublisher PD

Distribution and Abundance of the Blue Whale (Balaenoptera musculus indica) off Sri Lanka during the Southwest Monsoon 2018

Blue whales Balaenoptera musculus are the most abundant and widely distributed cetacean species in Sri Lankan waters. A vessel-based opportunistic line transect survey focusing on marine mammals was conducted in Sri Lankan waters between 24 June to 12 July 2018, while an ecosystem survey was performed by the R/V Dr. Fridtjof Nansen. The entire transect length was 2090 km within an area of 3895 km2. Overall, 72% (n = 57) of blue whale observations were group assemblages ranging between 1 and 5 individuals out of a total of 79 sightings. The largest aggregations of blue whales were recorded at the intersection of the submarine canyon off the coastline of Mirissa and busy shipping lanes between Dondra Head and Galle, where previous ship strikes were recorded. Overall, the average observed group size was 2.64 (CV, 12.34%; 95% CI, 2.07–3.38), the average group density was 0.0029 km−2 (CV, 35.96%; 95% CI, 0.00145–0.00610), and the total blue whale abundance within the survey area was 513 individuals (CV, 38.02%; 95% CI, 243–1083). These survey results fill vital knowledge gaps regarding the abundance and distribution of blue whales in Sri Lanka, which is essential for the establishment of management and conservation strategies.publishedVersio

PREDICTING SOLAR RADIATION FOR TROPICAL ISLANDS FROM RAINFALL DATA

Abstract: There are many correlations developed to predict incident solar radiation at a given location developed based on geographical and meteorological parameters. However, all correlations depend on accurate measurement and availability of weather data such as sunshine duration, cloud cover, relative humidity, maximum and minimum temperatures etc, which essentially is a costly exercise in terms of equipment and labour. Sri Lanka being a tropical island of latitudinal change of only 30 along the length of the country, the meteorological factors govern the amount of incident radiation. Considering the cloud formation and wind patterns over Sri Lanka as well as the seasonal rainfall patterns, it can be observed that the mean number of rainy days can be used to predict the monthly average daily global radiation which can be used for calculations in solar related activities conveniently

Comparative Assessment of Trace Element Accumulation in Traditional and Improved Rice (Oryza sativa L.) Varieties Grown with Organic, Chemical and Non-Fertilizers

Oryza sativa L., is the most widely grown rice in Sri Lanka. At present, farmers are using both organic and chemical fertilisers for the paddy cultivation. There is growing concern about heavy metal (mainly As, Cd and Pb) build up in the soils because they enter the soil and the plants via application of fertilisers (anthropogenic). Heavy metals are also found in the soil (geogenic). Cd and As are both nephrotoxic and neurotoxic, and there is a concern that they may be involved in the chronic kidney disease of uncertain etiology (CKDu) prevalent in the North Central Province and neighboring areas. According to the Food and Agriculture Organization (FAO), the maximum allowable limit (MAL) of Cd and As is 0.2 μg g-1. This study was conducted to compare the heavy metal accumulation in traditional and improved rice varieties grown with organic fertilisers, chemical fertilisers and without fertilisers. Total of 126 paddy samples (including seven traditional and seven improved rice varieties) grown with organic, chemical and non-fertiliser, were collected directly from the paddy fields in Rice Research and Development Institute (RRDI) at Batalagoda. Soil samples from paddy plots with different fertiliser treatments were collected. Heavy metal analysis was done at the Geology Department of the University of Peradeniya by using ThermoICapQ Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Rice cultivated with chemical fertilisers had the highest mean heavy metal concentrations. Cd concentration (0.32 μg Cd g-1) in traditional varieties grown with chemical fertilisers was significantly higher than in the other treatments. That value is 1.6 fold higher than the MAL. Organic fertiliser treated improved varieties had the lowest level of Cd and it was less than the MAL. All the other treatments had Cd levels more than the MAL. All treatments had lower content of As than the MAL. Taken as a whole, macro-nutrients (K, Ca, Mg) were higher in the chemical fertiliser treated rice than that of organic treated rice. Heavy metals and macro-nutrient concentrations varied from variety to variety.Keywords: Chemical fertiliser, Heavy metals, Improved rice, Organic fertilizer, Traditional ric