Keanekaragaman Jenis Arthropoda di Gua Putri dan Gua Selabe Kawasan Karst Padang Bindu, OKU Sumatera Selatan

Penelitian tentang keanekaragaman jenis Arthropoda di Gua Putri dan Gua Selabe Kawasan Karst Desa Padang Bindu, Kecamatan Semidang Aji, Kabupaten Ogan Komering Ulu, Sumatera Selatan telah dilakukan pada bulan Februari-Agustus 2008. Penelitian ini bertujuan untuk mengetahui keanekaragaman jenis Arthropoda, yang ada di dalam Gua Putri dan Gua Selabe. Metode yang digunakan adalah koleksi langsung, perangkap sumuran (pitfall trap) dan perangkap cahaya (light trap). Hasil yang didapat menunjukkan bahwa terdapat perbedaan jumlah individu Arthropoda di Gua Selabe (_ = 835) (uji t, P = 0, 023896) dengan di Gua Putri (_ = 441). Nilai indeks keanekaragaman jenis Artrhropoda pada Gua Selabe (2,1143) lebih tinggi dibandingkan dengan Gua Putri (1,9669). Jenis-jenis Arthropoda yang ditemukan di Gua Putri sebanyak 12 jenis dan di Gua Selabe sebanyak 20 jenis. Jenis-jenis tersebut yaitu Araneidae sp. 1, Blattidae sp. 1, Blattidae sp. 2, Blattidae sp. 3, Blattidae sp. 4, Diestrammenna sp, Diptera sp. 1, Heteropoda sp, Hymenoptera sp. 1, Labiida sp, Lampyridae sp. 1, Nocticola sp, Parathelpusa tridentata, Potalinda sp, Rhaphidophora sp, Staphylinidae sp. 1, Stillocellus sp, Stygophrynus sp, Squtigerra sp, Tricoptera sp. 1

Scalar dissipation rate and scales in swirling turbulent premixed flames

© 2016 by The Combustion Institute. Published by Elsevier Inc. Simultaneous Rayleigh scattering and OH LIF imaging measurements of temperature and OH were used to investigate the properties of turbulent premixed flames, including the nature of the 2D thermal structures and scalar dissipation rate in the Cambridge/Sandia swirling bluff body stabilized flames, with and without the effect of swirl. Swirl creates enhanced turbulence as well as outer flow entrainment, and disrupts the pre-flame zone significantly, whilst the high temperature reaction zone as marked by OH remains relatively intact. In particular, the temperature at the location of maximum OH gradient shows very low variance across the flame region. The 2D image analysis of OH and temperature shows that the corresponding 2D gradients are aligned up to a distance of half the laminar flame thickness away from the flame front, deviating significantly in the case of swirling flames beyond that region. As in previous investigations in diffusion flames, the mean width of the observed thermal structures increases from 300 to 600 μm near the flame, with a main mode around the laminar flame thermal width in the unswirled case. The correlation between 2D thermal dissipation and variance of the reaction progress variable extracted from the images shows a direct proportionality, with a slope which agrees well with theory in the region of high turbulence away from the base. At the base of the flame where turbulence is low, the local scalar dissipation becomes a function of the local temperature via the thermal diffusivity

Composition and diversity of phytoplankton from mangrove estuaries in Sarawak, Malaysia

The composition and diversity of phytoplankton were studied along with physico-chemical parameters of water of two mangrove-dominated estuaries i.e., Kuala Sibuti (KS) and Kuala Nyalau (KN), Sarawak, Malaysia. A total of 46 species of phytoplankton with the mean density of 147000 cells L-1 were recorded from KS estuary i.e., 3 species of Cyanophyceae; 22 species of Bacillariophyceae; 20 species of Dinophyceae and 1 species of Chlorophyceae. The recorded mean density of phytoplankton was 113000 cells L-1 with 33 species from 19 genera from KN estuary, in which 19 species were from Bacillariophyceae; 12 species were from Dinophyceae; 1 species was from Cyanophyceae and 1 species was from Chlorophyceae. In both the estuaries, the species composition was found to be in an order of Diatom>Dinoflagellate>Cyanophyceae>Chlorophyceae. Canonical Correspondence Analysis (CCA) revealed that the abundance of Bacillariophyceae and Dinoflagellates was influenced by salinity and conductivity along with ammonium and phosphate while the abundance of Chlorophyceae was influenced by temperature, TDS, DO and pH in KS. The influence of salinity and conductivity along with PO4 and NH4 on the abundance of Bacillariophyceae, Dinoflagellates and Chlorophyceae were observed in KN

Seasonal variation of water characteristics in Kuala Sibuti river estuary in Miri, Sarawak, Malaysia

This paper presents the water characteristics of Kuala Sibuti river estuary, which is margined by pristine mangrove forest. For this purpose, nutrients, chlorophyll a and environmental parameters were investigated for 12 months. Physical, chemical and biological parameters of this estuarine water followed a seasonal rhythm and induced by the annual cycle of the monsoon. Surface water temperature ranged from 27.4°C to 32.2°C with a wide variety of salinity from 0.70 PSU to 27.10 PSU followed by Dissolved Oxygen (DO) from 1.94 to 6.71 mg/L. The concentration of chlorophyll a was found to be varied from 0.02 to 0.16 mg/m3. Nitrate, phosphate and ammonium concentrations ranged from 0.40 to 3.53mg/L, 0.01 to 1.92 mg/L and 0.06 to 1.24 mg/L, respectively. Pearson correlation coefficients showed a significant relationship between nitrate and TDS, nitrate and pH, ammonium and salinity, temperature and salinity, temperature and TDS, phosphate and light attenuation in this estuarine environment. The estuary was found to be mesohaline in nature. Estuarine Water Quality Index (EWQI) calculated from phosphate (PO4), suspended matter (SM) and dissolved oxygen (DO) indicate very good quality (4.95). Significantly seasonal difference for salinity, water temperature and, TDS were observed probably related to tidal flow and upstream river runoff

Seasonal distribution of zooplankton composition and abundance in a sub-tropical mangrove and salt marsh estuary

Zooplankton composition and abundance at two stations located in exposed (station I) and protected (station II) areas of Bakkhali sub-tropical estuary, Cox's Bazar, Bangladesh were investigated monthly from January 2006 to December 2006. Thirty-three zooplankton taxa were identified. The major groups of zooplankton encountered were Copepoda, Chaetognatha, Mysidaceae, Luciferidae, Amphipoda, Acetes, Hydromedusae, Cladoceran, Decapod and fish larvae. The percent composition of Copepoda was the highest (79.5-84.8%) among zooplankton groups followed by Chaetognatha (5.5-6.0%) and Mysidaceae (3.3-6.8%). The abundance of zooplankton was relatively higher (87674individuals/m3) in protected (mangrove) as compared to exposed (salt marsh; 68719 individuals/m3) site during the study period. Canonical Correspondence Analysis indicated that the abundance of copepods was influenced by rainfall, water temperature and transparency in this estuarine environment, and considered coastal and estuarine dominant

Phytoplankton in tropical mangrove estuaries: role and interdependency

Mangrove estuaries are claimed to be productive and important breeding grounds for fishery resources. The role of particulate organic matter (POM), especially derived from decomposed litter detritus, is well documented in mangrove estuaries. However, being a primary producer, phytoplankton may play a significant role, which has not been well discussed, in governing the productivity of mangrove estuaries. Based on relevant published literature, this paper focuses on the role of phytoplankton in mangrove estuaries in the tropical coastal region and their interdependency. Analysis reveals that there are two-way interactions between phytoplankton and mangrove estuaries. The POM enriched water in mangrove estuaries acts as an ideal medium for phytoplankton succession. Simultaneously, diversified phytoplankton assemblages play a significant role in the food web of the estuarine mangrove ecosystem. Biomass and diversity of phytoplankton are influenced by nutrient and environmental parameters in mangrove estuaries and, concurrently, phytoplankton play a significant role in fish diversity and primary production in the same system. This review reveals that the inconsistent relationships between mangroves and coastal production could probably be due to the influence of seasonal changes. This paper unveils the latent potential and role of phytoplankton in tropical mangrove estuaries, which could be a source of thought for future research in this arena

Consumer Engagement with Social Media Platforms: A Study of the Influence of Attitudinal Components on Cutting Edge Technology Adaptation Behaviour

Despite pervasive use of digital devices, the influence of simultaneous and combined attitudinal components on consumers’ social media adaptation behaviours remains understudied. This research aims to address this gap in the literature by examining the influence of combined attitudinal components on consumers’ continuous interaction with social media platforms. An online survey was conducted to obtain robust quantitative data on consumers’ interaction and engagement with cutting edge technology such as social media. The findings indicate that consumers’ combined cognitive (perceived opportunity, perceived social influence and perceived control) and affective (enjoyment, self-enhancement, trust and fear) attitudinal components are the antecedents to consumers’ positive and negative adaptation behaviours of social media platforms. Consumers continuously engage with cutting edge social media platforms, either in positive adaptation behaviour (exploration to maximise or exploitation to satisfice social media led benefits) or negative adaptation behaviour (explore to revert from or avoid social media platforms) influenced by combined cognitive and affective attitudinal attributes. The study enriches and advances existing literature by identifying and analysing the influence of both cognitive and affective attitudinal attributes influencing consumers’ positive and negative adaptation behaviours of cutting edge digital technology such as social media platforms. The study helps marketers and IS managers in profiling consumers and understanding consumption patterns while interacting with cutting edge social medial platforms

Distribution of aquatic macrophytes in the coastal area of Salimpur, Chittagong, Bangladesh.

This preliminary study was conducted to investigate the distribution pattern of the aquatic macrophytes in the inter-tidal coastal belt of Salimpur, Chittagong. During this study, 3 species of mangrove, i.e., Sonaratia apetala, Avicennia marina and Acanthus ilicifolius, 1 species of wild rice related to salt marsh grass, i.e., Porteresia coarctata, 3 species of macro-algae, i.e., Ulva intestinalis, Catenella nipae and Dictyota dichotoma and 1 species of poison lily Crinum defixum were identified from this coast. The dominant macrophyte was planted Sonaratia apetala, followed by Porteresia coarctata in the coast line of Salimpur. Considering from the ecological and economic view, especially Catenella nipae, could be an important living resource for cultivation and sea ranching in this area. Besides, the importance of these aquatic inter-tidal macrophytes for fishery resources and overall ecosystem processes should not be over looked in this coastal area

Drying effect on the properties of traditionally processed sago starch

Local people in Sarawak, Malaysia produce sago starch, commonly referred as lemantak, using traditional method for authentic meals and delicacies. The quality of lemantak degrades with time due to its high moisture content limiting the potential for a wider market, and hence affecting the socio-economy of those whose livelihood depends on sago starch production. The objective of the present work was to evaluate the changes in the properties of traditionally processed dried Sarawak sago starch. In order to achieve this, sago starch was extracted using a well-established traditional process and was dried at 40°C to produce sago starch with moisture contents of 40%, 30%, 20% and 10% wet basis. The effect of moisture content on the physical properties was studied through colour analysis, microscopic analysis, and particle size distribution. Analysis on resistant starch content was also performed. Changes on the hydration and functional properties was monitored by measuring the water absorption index (WAI), water solubility index (WSI), swelling capacity (SC), and gelatinisation behaviour. Lastly, Fourier transform-infrared spectroscopy (FT-IR) was applied to observe the changes in amorphous and crystalline areas. The physical properties analysis showed changes in starch colour and granule surface; but the change on granule size varied. Dried starch with lower moisture content exhibited higher resistant starch, absorption index, and peak temperature, but lower solubility index, swelling capacity, peak viscosity, crystalline index, and amorphous index. It is suggested that moisture content affected the changes in traditionally processed sago starch properties which was influenced by few components namely polyphenol, lipid, amylose-lipid complex, and inter-molecular hydrogen bon

Inter-linkage among some physico-chemical and biological factors in the tropical mangrove estuary

The interaction between abiotic and biotic parameters in an ecosystem usually shows health and functioning of the system. Thus, some physico-chemical parameters, phytoplankton abundance, chlorophyll a and primary production of the mangrove estuary in Sarawak, Malaysia were extensively investigated from January 2013 to December 2013 in order to establish the inter-linkage among them. The Pearson correlation coefficient revealed a significant relation between atmospheric and water temperatures (r = 0.692). Similarly, surface water temperature showed a significant positive correlation with salinity (r = 0.744), TDS (r = 0.708) and conductivity (r = 0.776). The light extinction coefficient (LEC, K) changed negatively in relation to TDS (r =-0.623), conductivity (r =-0.644) and surface water temperature (r =-0.766). Ammonium showed a negative correlation with rainfall (r =-0.620) but a positive correlation with salinity (r = 0.600). The biological variable such as phytoplankton abundance was found to be positively correlated with chlorophyll a (r = 0.692), ammonium (r = 0.645) and silica (r = 0.644) and negatively with rainfall (r =-0.644). The canonical correspondence analysis revealed a strong positive correlation between environmental parameters and phytoplankton species. The analysis of variance disclosed significant seasonal differences in salinity, water temperature, TDS, conductivity, LEC, ammonium and chlorophyll a