Bray-Curtis Cluster Analysis Research Articles

A rapid assessment of Scleractinian and non-Scleractinian coral growth forms along the Saudi Arabian coast, Red Sea

In this study we assessed the current status of coral reefs along the Saudi Arabian coast of the Red Sea. Among the three growth forms of Acroporid corals, the branching forms were found to dominate in the Farassan Islands (44.55%±11.10% cover) followed by tabular forms in the Doga Islands (ranging between 18%±6.47% and 18.30%±9.47% cover). Digitate forms were rarely found along the coast except at Maqna. Among the five growth forms of non-Acroporid corals, we observed maximum cover of branching forms in the Yanbu offshore area (58.89%±15.11% cover) followed by the Jeddah coast (24.76%±14.04% cover). The Millepora spp., a non-Scleractinian coral, was abundant at all the near-shore sites, such as Jeddah (10.70%±8.21%) and Al-Wajh (9.81%±6.69%). The live coral cover (including both Scleractinian and non-Scleractinian corals) of Saudi Red Sea coast was seen to be higher in the north and gradually decrease towards the south. Principal Component analysis showed that the contribution of Acroporid corals was greater in the southern region than in the northern and middle regions, but vice-versa in the case of non-Acroporid corals. Bray-Curtis cluster analysis categorized all the study sites into two major clusters with 60% similarity. Among them, one cluster-forming sites from Maqna to Masturah (Northern region) and the second one comprised the middle and southern regions (Jeddah to Farassan Islands), and one outlier Rabigh.

Statistical Assessment of Water Quality Parameters for Pollution Source Identification in Sukhnag Stream: An Inflow Stream of Lake Wular (Ramsar Site), Kashmir Himalaya

The precursors of deterioration of immaculate Kashmir Himalaya water bodies are apparent. This study statistically analyzes the deteriorating water quality of the Sukhnag stream, one of the major inflow stream of Lake Wular. Statistical techniques, such as principal component analysis (PCA), regression analysis, and cluster analysis, were applied to 26 water quality parameters. PCA identified a reduced number of mean 2 varifactors, indicating that 96% of temporal and spatial changes affect the water quality in this stream. First factor from factor analysis explained 66% of the total variance between velocity, total-P, NO3–N, Ca2+, Na+, TS, TSS, and TDS. Bray-Curtis cluster analysis showed a similarity of 96% between sites IV and V and 94% between sites II and III. The dendrogram of seasonal similarity showed a maximum similarity of 97% between spring and autumn and 82% between winter and summer clusters. For nitrate, nitrite, and chloride, the trend in accumulation factor (AF) showed that the downstream concentrations were about 2.0, 2.0, and 2.9, times respectively, greater than upstream concentrations.

Bird Diversity and Distribution in relation to Urban Landscape Types in Northern Rwanda

Using the point count method, linear mixed models, Shannon's diversity index, and Bray-Curtis cluster analysis, we conducted a study of the effect of urban fabric layout on bird diversity and distribution in northern Rwanda. The results showed a significant effect of city landscapes on bird richness and relative abundance; residential neighborhoods, institutional grounds, and informal settlements had the highest species diversity in comparison to other microlandscape types. Riversides were characterized by specialized bird species, commonly known to be restricted to wetland environments. Built-up areas and open field landscapes had comparable results. One Albertine Rift endemic bird species, the Ruwenzori Double-collared Sunbird (Cinnyris stuhlmanni), was recorded. Three migratory birds were found in Musanze city for the first time: the Common Sandpiper (Actitis hypoleucos), the Spotted Flycatcher (Muscicapa striata), and the Willow Warbler (Phylloscopus trochilus). Two bird species have not been previously reported in Rwanda: the Garden Warbler (Sylvia borin) and the Lesser Spotted Eagle (Aquila pomarina). The implications of this study are particularly relevant to urban decision makers who should consider the existence of a great diversity of avian fauna when developing and implementing master plans, especially when villages and cities are in proximity of protected areas or natural reserves.

Deep sea benthic foraminifera as proxies for palaeoclimatic fluctuations in the New Caledonia Basin, over the last 140,000years

abstract Article history:Received 17 September 2012Received in revised form 19 June 2013Accepted 28 August 2013Available online 4 September 2013Keywords:New Caledonia BasinTasman SeaQuaternarySouthwest PacificOceanforaminiferapalaeoenvironment The New Caledonia Basin (NCB), SW Pacific, a deep bathyal to abyssal basin bordered by the Lord Howe Rise tothe west and the Norfolk Ridge to the east, has received little scrutiny with regard to the taxonomic diversityofbenthicorganismsinitsQuaternarytoRecentdeepseasediments.In2001,GravityCore4(GC4)wasextractedfrom the NCB and the uppermost 141 cm, representing approximately the last 140,000 years, was investigatedfor chemical isotopic, carbonate, non-carbonate and trace element signatures. In this study, subsamples of thesame uppermost 141 cm of GC4 were picked and sorted for all foraminiferal taxa. At selected intervals in GC4,allbenthicspecieswereidentifiedandcountedformeasuresofrelativeabundance.Atotalof161speciesofben-thic foraminifera were obtained from the core and 46 species occurred in sufficient numbers to investigatechangingpatternsandtrendsinbiodiversityandrelativeabundance.Changesfoundwithintheforaminiferaldis-tribution down the core can be related to some oceanic and palaeoclimatic fluctuations during the last~140,000 years. Within GC4, two distinct foraminiferal assemblages were detected using Bray–Curtis clusteranalysis and Multidimensional Scaling (MDS) analysis. Foraminiferal Assemblage 1 occurs in lower bathyal toabyssal depths and was largely influenced by high oxygen levels at the sediment–water interface throughoutMarine Isotopic Stage (MIS) 6–3 (approximately 128 –25 ka). Foraminiferal Assemblage 2 dominated theupper bathyal shelf during MIS 2 (approximately 25–10 ka), with surface waters characterised by high sea sur-faceproductivity(SSP)andeutrophicconditions.DuringthetimecoveredbyGC4,thereareinstanceswheretherelative abundanceofthe dominanttaxonEpistominella exigua(Brady)and other key taxadecreasesand oppor-tunistic species of Uvigerina, adapted to lower oxygen levels, increase in relative abundance, indicating a shift ofconditions at the sediment–water interface. Factors that influence the foraminiferal assemblages include envi-ronmentalsetting,SSP,oxygenlevelsatthesediment–waterinterfaceandtransportationbyoceaniccurrentsys-tems operating within the region.© 2013 Elsevier B.V. All rights reserved.

Seasonality in fish assemblage structure in an East African mangrove creek

The spatial and seasonal structures of fish assemblages in a tropical mangrove tidal creek, Tudor, Kenya, were analysed from monthly survey data, extending from October 2007 to July 2008, and covering the north-east (NEM; October–March) and south-east (SEM; April–July) monsoon seasons. A total of 2 118 individuals, representing 84 species belonging to 49 families, were caught. Gerres oyena, Terapon jarbua and Lutjanus fulviflamma were the dominant species in all seasons. There was within-creek seasonal variability in species abundance and diversity. Overall, the mean density (individuals m–2) was higher during the SEM season (0.368; SE 0.078) than the NEM season (0.255; SE 0.041). The NEM season had significantly more species (n 69) than the SEM season (n 63) (χ2 = 317.891, p < 0.0001). Two-way ANOVA indicated the influence of season and habitat on abundance of some species. The abundance of creek-resident species was significantly influenced by site whereas abundance of creekdependent and transient species was influenced by interaction between seasons and stations. Bray-Curtis cluster analysis defined two species assemblages, reflecting differences in temporal and spatial use of the creek by the fish species. Correspondence analysis indicated that seasonal fish assemblages were only distinct at the mouth of the creek with less clear seasonal structure in the upper region of the creek.

THE ABUNDANCE AND SPATIAL DISTRIBUTION OF PLANKTON COMMUNITIES IN BANGGAI ISLANDS WATERS

&lt;p&gt;Banggai Islands waters are mixing area between Banda Sea and Makassar Sea, thus resulting in the existence of many unique marine ecosystems. This conditon might also lead to the occurrence of unique and specific plankton community in the oceanic ecosystem of Banggai Islands. This research was conducted in 26 June to 8 July using Baruna VIII research vessel. Phytoplankton and zooplankton samples were collected in 14 stations using Kitahara and NORPAC plankton net. The plankton data in this research was analyzed with Bray-Curtis Clustering Analysis (Single Link), linear regression and Pearson correlation matrix. The results showed that zooplankton abundance was highest at the strait between Liang and Labobo Island, while phytoplankton was found abundant at eastern Tinangkung Island. On the other hand, Mesamat Bay was found having very low abundance of zooplankton and phytoplankton, which probably related to low nutrient availability in the water column. Calanoids, cyclopoids, and oikopleurans were dominant taxa with widest spatial distribution and highest importance value in zooplankton community of Banggai Islands. Meanwhile Chaetoceros, Rhizosolenia and Thalassiothrix were the dominant genus with widest spatial distribution and highest importance value in phytoplankton community. The result of clustering analysis showed that there were three stations with unique plankton community, and was found very different from the planktonic community in other stations. It was interesting to note that bottom-up control by nutrient availabilty, and top-down control by predator-prey interaction, probably not the main factor responsible for the unique pattern of plankton community structure of Banggai Islands.&lt;/p&gt; &lt;p&gt;Keywords: plankton community, Banggai islands waters, Bray-Curtis clustering analysis, biological indices.&lt;/p&gt;

THE ABUNDANCE AND SPATIAL DISTRIBUTION OF PLANKTON COMMUNITIES IN BANGGAI ISLANDS WATERS

Banggai Islands waters are mixing area between Banda Sea and Makassar Sea, thus resulting in the existence of many unique marine ecosystems. This conditon might also lead to the occurrence of unique and specific plankton community in the oceanic ecosystem of Banggai Islands. This research was conducted in 26 June to 8 July using Baruna VIII research vessel. Phytoplankton and zooplankton samples were collected in 14 stations using Kitahara and NORPAC plankton net. The plankton data in this research was analyzed with Bray-Curtis Clustering Analysis (Single Link), linear regression and Pearson correlation matrix. The results showed that zooplankton abundance was highest at the strait between Liang and Labobo Island, while phytoplankton was found abundant at eastern Tinangkung Island. On the other hand, Mesamat Bay was found having very low abundance of zooplankton and phytoplankton, which probably related to low nutrient availability in the water column. Calanoids, cyclopoids, and oikopleurans were dominant taxa with widest spatial distribution and highest importance value in zooplankton community of Banggai Islands. Meanwhile Chaetoceros, Rhizosolenia and Thalassiothrix were the dominant genus with widest spatial distribution and highest importance value in phytoplankton community. The result of clustering analysis showed that there were three stations with unique plankton community, and was found very different from the planktonic community in other stations. It was interesting to note that bottom-up control by nutrient availabilty, and top-down control by predator-prey interaction, probably not the main factor responsible for the unique pattern of plankton community structure of Banggai Islands. Keywords: plankton community, Banggai islands waters, Bray-Curtis clustering analysis, biological indices.

Field and GIS based post-tsunami assessment of Scleractinian coral cover in the Aerial Bay group of Islands, North Andaman, India

The Aerial Bay group of Islands are one of the diverse environments of Andaman & Nicobar Islands, where the coral reefs degraded much due to the natural calamity of tsunami on 26 December 2004. After this event, the entire North Andaman Islands got elevated, which resulted in the exposure of coral reefs during low tide, causing mass mortalities and destructions to this pristine environment. In order to understand the current status, bio-physical monitoring of coral reefs was carried out and compared with classified coral map of pre-tsunami period. A decline from 411.14 to 68.25 hectares (ha) of live coral area was observed in the Aerial Bay group of Islands. The dead corals and other abiotic factors (sand, mud and rubble) were observed to be 317.33 and 25.56 ha respectively, based on comparisons between ground truthed and classified pre-tsunami coral map (2004) processed in ArcGIS®. The detrended correspondence analysis of coral life form categories showed maximum cover of dead coral with algae, in comparison with the live corals. Bray-curtis cluster analysis revealed three different groups of study sites with 60 % similarity based on life-form categories within the coral reef environment.

Relation Between Physico-chemical Limnology and Crustacean Community in Wular Lake of Kashmir Himalaya

The present study scrutinizes the seasonal variation in the distribution of crustacean zooplankton in relation to physico-chemical liminology of Wular lake. Water samples were collected from five study sites during September 2010-August 2011. Remarkable spatial and temporal variations were observed among the different study sites. Among the parameters recorded water temperature showed positive correlation with pH (p<0.01) and orthophosphate (p<0.05).Transparency showed a significant negative correlation with total alkalinity (p<0.01), free carbon dioxide (p<0.01) and ammonical nitrogen (p<0.01). Crustacean zooplankton were collected by filtering 100 L lake water through a 30 microm nytal mesh and preserved in 4% formalin. A total of 42 taxa of crustacean were recorded, among them 23 species belonged to Cladocera, 16 to Copepoda and only 3 to Ostracoda. Species diversity and density depicted an abrupt up surge on the advent of warmer period (extending from March). Among the various sites a maximum of 40 species were recorded from a single biotope (site III) against the minimum of only 17 species being recorded from site I. Bray-Curtis cluster analysis showed close similarity (0.928-0.944%) between summer and autumn in terms of species diversity. Pearson correlation coefficient of the various physico-chemical parameters of water with crustacean zooplankton depicted that not only a single but multiple factors govern over the distribution and diversity of crustacean in the lake.

Human-induced Disturbances Influence on Bird Communities of Coastal Forests in Eastern Tanzania

Aims: To assess the influence of human-induced disturbances on bird communities. Study Design: Longitudinal study. Place and Duration of Study: Four forests; Kion/Zaraninge, Kwamsisi/Kwahatibu, Msumbugwe and Gendagenda in Pangani–Saadani ecosystem, from October 2010 to January 2011. Methodology: Eight permanent transects, each 500 m long stratified into forest core and forest edge habitats were used in each forest to identify types and quantify levels of human-induced disturbances, determine bird species composition, diversity and richness, and abundance. Therefore three circular plots, each 20 m radius were allocated at beginning, middle and end of each transect. The level of disturbance was assessed using four disturbance indicators; tree lopping, human trails, Pit-sawing and animal snaring while Research Article British Journal of Applied Science & Technology, 3(1): 48-64, 2013 49 bird species were identified by sight and call. One-way Analysis of Variance was used to test for differences in bird abundance between forests. Moreover, Shannon-Wiener Diversity Index (H’) was calculated for each forest to assess species diversity and evenness, and Bray-Curtis Cluster analysis was used to determine similarity in bird species composition between the forests. Results: A total of 564 individuals composed of 88 bird species distributed in ten Orders were recorded. The level of Pit-sawing and lopping differed significantly between forests (P<.05) with Msumbugwe being more disturbed than the rest. Bird abundance differed significantly between the forests (P<.05) with the highest abundance occurring in Msumbugwe. As expected, species richness and diversity were greater in least disturbed forests-Kiono/Zaraninge and Kwamsisi/Kwahatibu than in the highly disturbed forest, but forest dependent species were not significantly different between the study forests. Apparently, only Pit-sawing was found to correlate with bird abundance (P<.01) whereas similarities in species composition were evident with Kion/Zaraninge and Gendagenda exhibiting much overlap. Conclusion: Increasing forest disturbances seems to negatively impact on distribution of birds thus challenging conservationists to devising sustainable forest management strategies in order to sustain bird diversity and abundances in these unique forests.

Role of Different Variables on Site-Specific Isolation And Distribution Patterns of Soil Mycoflora from Varanasi

During present study, 513 isolates were recovered from 15 different experimental sites. For fungal recovery, PDA medium proved better over Czapek's dox agar medium (CDA), while Waksman dilution method showed higher isolates recovery than Warcup's soil plate method. Thirty filamentous fungi were recovered of which Aspergillus, Alternaria, Cladosporium, and Fusarium were dominant. Aspergillus niger and A. fumigatus showed a high frequency of occurrence and were isolated @ 80 x103 CFU/g and 47x 103 CFU/g, respectively from dry, moist and humid soil samples, while Penicillium notatum (37x103 CFU/g), Nigrospora oryzae (30 x103 CFU/g), Rhizopus nigricans (32x103 CFU/g), Trichoderma viride (24x103 CFU/g) were isolated with moderate frequency. Fifty three isolates were recovered from site 10 (Agriculture field, BHU) which was highest whereas, 12 isolates were recovered from site 1 (Cantt Railways Station). Consequently, the site 10 had the maximum CFU value (53x103 CFU/g) whereas site 1 had the lowest (12 x103 CFU/g). A higher percentage of soil fungi isolated have preferred the acidic pH range. Mean of fungal isolates was higher in moist (37.60), followed by humid (34.50) and dry (30.20) conditions. Bray-Curtis cluster analysis was done to understand that several variables are responsible for the diversity and occurrence of soil fungi.

Diversity and ecology of lianas in tropical dry evergreen forests on the Coromandel Coast of India under various disturbance regimes

In this study we attempted to explore patterns of diversity, abundance, climbing and dispersal mode of lianas in relation to disturbance in 40 Indian subtropical dry forests. The sites were selected to represent four disturbance categories: relatively undisturbed, moderately disturbed, much disturbed and heavily disturbed. All lianas ≥1cm dbh were counted, which resulted in a total amount of 5689 individuals of lianas, representing 77 species in 62 genera and 32 families. Liana species richness and abundance increased with forest disturbance, but the liana basal area values showed an opposite trend, with high scores in undisturbed sites. Twining was the main climbing mechanism (61.3%) and zoochory (59.6%) was the main dispersal mode in all the four forest categories. Application of Bray–Curtis cluster analysis produced three distinct clusters in which the much disturbed category was more distant from the others. High abundance of large lianas in undisturbed sites and that of the invasive Lantana camara in heavily disturbed site signals the conservation significance of the less disturbed study sites. The predominance of zoochorous dispersal indicates the faunal dependence of lianas, besides of host trees, thus underlining the need for a holistic approach in biodiversity conservation of this and similar tropical forests.

ZOOPLANKTON SPATIAL DISTRIBUTION AND COMMUNITY STRUCTURE IN BANGGAI SEA

&lt;p&gt;Banggai Sea is an interesting ecosystem due to mixing influences from Banda Sea in the west and Maluccas Sea in the east. Therefore, a unique zooplankton community structure and specific distribution pattern should be found in this area. This research was carried on using Baruna Jaya VIII research vessel and samples were collected in 14 sampling stations. Vertical towing using NORPAC plankton net (300 μm) was conducted to collect zooplankton samples. Result showed that inner Mesamat Bay had the lowest abundance of zooplankton, probably due to low water quality resulted from anthropogenic activity. Meanwhile the strait between Liang and Labobo Island had the highest zooplankton abundance in Banggai Sea. Calanoids was the dominant zooplankton taxa in the ecosystem and contributing 55.7% of total density of zooplankton community. The highest importance value made this taxa to be very important factor that regulates the lower trophic level organisms. Results also showed that zooplankton was distributed nearly uniform in eastern but aggregated to several stations in western Banggai Sea. Zooplankton abundance was higher in the central of Banggai Sea, compared to western and eastern area. According to Bray-Curtis clustering analysis the strait between Liang and Labobo Island has unique zooplankton community structure. This might happened due to mixing of water from two highly productive seas that influenced the Banggai Sea ecosystem. From this research we conclude that this strait probably was the zooplankton hot spot area which might also indicate that this area also a hot spot of fishes in the Banggai Sea.&lt;/p&gt;&lt;p&gt;Keywords: spatial distribution, zooplankton, community structure, hot spot, Banggai&lt;/p&gt;

ZOOPLANKTON SPATIAL DISTRIBUTION AND COMMUNITY STRUCTURE IN BANGGAI SEA

Banggai Sea is an interesting ecosystem due to mixing influences from Banda Sea in the west and Maluccas Sea in the east. Therefore, a unique zooplankton community structure and specific distribution pattern should be found in this area. This research was carried on using Baruna Jaya VIII research vessel and samples were collected in 14 sampling stations. Vertical towing using NORPAC plankton net (300 μm) was conducted to collect zooplankton samples. Result showed that inner Mesamat Bay had the lowest abundance of zooplankton, probably due to low water quality resulted from anthropogenic activity. Meanwhile the strait between Liang and Labobo Island had the highest zooplankton abundance in Banggai Sea. Calanoids was the dominant zooplankton taxa in the ecosystem and contributing 55.7% of total density of zooplankton community. The highest importance value made this taxa to be very important factor that regulates the lower trophic level organisms. Results also showed that zooplankton was distributed nearly uniform in eastern but aggregated to several stations in western Banggai Sea. Zooplankton abundance was higher in the central of Banggai Sea, compared to western and eastern area. According to Bray-Curtis clustering analysis the strait between Liang and Labobo Island has unique zooplankton community structure. This might happened due to mixing of water from two highly productive seas that influenced the Banggai Sea ecosystem. From this research we conclude that this strait probably was the zooplankton hot spot area which might also indicate that this area also a hot spot of fishes in the Banggai Sea.Keywords: spatial distribution, zooplankton, community structure, hot spot, Banggai

The influence of the monsoon climate on phytoplankton in the Shibpukur pool of Shiva temple in Burdwan, West Bengal, India

AbstractA total of 44 taxa were observed in monthly sampled phytoplankton of the Shibpukur pool in Burdwan, West Bengal between March, 2010 and February, 2011. The most abundant taxa belong to Charophyta, followed by cyanobacteria, diatoms and euglenoids. Bio-indication shows that the pool community preferred low alkaline, low mineralized and low organically polluted water. The total phytoplankton density showed its maximum values in May, 2010. The Shannon-Weaver diversity index and the Pielou evenness value were found to be highest during the post-monsoon season. The Simpson dominance index and the Margalef index of richness were highest in the pre-monsoon season. The total phytoplankton density showed a highly significant positive correlation with pH and salinity and significant positive correlation with air temperature, water temperature, dissolved oxygen and total suspended solids. Among the reported 44 phytoplankton taxa only 3 showed a random distributional pattern. The Bray-Curtis Cluster analysis and the comparative statistics reveal two groups of phytoplankton assemblages in respect to the monsoon seasons. The successive communities form a continuum corresponding to Colwell’s Constancy (C) category. The calculated indices, CCA, and bio-indication analysis exhibit a low pollution level in the Shibpukur pool that can be used as a model of aquatic community dynamics under seasonal fluctuation in the monsoon climate, applicable for monitoring of water bodies in the West Bengal Province

Biomass size spectra of mesozooplankton in the Chukchi Sea during the summers of 1991/1992 and 2007/2008: an analysis using optical plankton counter data

AbstractMatsuno, K., Yamaguchi, A., and Imai, I. 2012. Biomass size spectra of mesozooplankton in the Chukchi Sea during the summers of 1991/1992 and 2007/2008: an analysis using optical plankton counter data. – ICES Journal of Marine Science, 69: . An optical plankton counter was used to examine the regional characteristics of the zooplankton communities in the Chukchi Sea during the summers of 1991, 1992, 2007, and 2008. Zooplankton abundance and biomass ranged from 5000 to 1 170 000 ind. m−2 and 0.2 to 10.9 g dry mass m−2, respectively. Based on zooplankton biovolume in equivalent spherical diameter (ESD) in 48 bins, one every 0.1 mm between 0.25 and 5.0 mm, a Bray–Curtis cluster analysis classified zooplankton communities into four groups (A–D). No changes were observed in zooplankton communities south of the Lisburne Peninsula (group A) throughout the 4 years, but there were differences north of the Peninsula, with group B (normal, intermediate biomass) observed in 1991/1992, group D (low biomass) in 2007, and group C (predominance of barnacle larvae) in 2008. Analysis of the normalized biomass size spectra for the groups indicated that groups A and C were very productive, so the zooplankton community south of the Lisburne Peninsula was consistently highly productive, which may be because of the continuous inflow of Pacific Water rich in nutrients. Zooplankton communities north of the Lisburne Peninsula varied greatly from year to year, which may be related to interannual changes in sea-ice extent.

The influence of canopy structure and tidal level on fish assemblages in tropical Southeast Asian seagrass meadows

Seagrass meadows support abundant and diverse fish assemblages, but there are very few studies on the relation between seagrass beds with distinctly different plant canopies and their associated fish fauna. In the present study, fish assemblages were investigated by underwater visual census at intertidal and subtidal sites with varying seagrass species composition, shoot density, biomass, and leaf area index (LAI) on two small coral islands in the Spermonde Archipelago, Indonesia. We investigated (1) whether fish assemblages in distinctly different seagrass beds differ regarding community parameters, and (2) whether seagrass parameters affect fish abundances. Overall, more than 120 fish taxa were found. Bray–Curtis cluster analysis and non-Metric Multidimensional Scaling ordination (nMDS) showed site-specific similarities for fish assemblage structure with a distinct separation into subtidal and intertidal sites. Species accumulation curves for gamma diversity, single study sites, and the two most diverse fish families (Labridae, Pomacentridae), suggesting that species numbers are likely to increase with diel sampling. Total fish abundance and abundance for six out of the nine most common species varied distinctly among the study sites. The study indicates that seagrass beds with differing canopy parameters support distinct fish assemblages that differ with respect to species richness, dominant species, and the abundance of total and most common fish species. These differences are likely due to different canopy structures and water depth.

Spatiotemporal Distribution of Harmful Algal Flora in the Tropical Estuarine Complex of Goa, India

Mandovi and Zuari estuarine complex is monsoon-influenced estuaries located along the central west coast of India. During the past few years, there has been an increase in nutrient loading specially during monsoonal runoff which is responsible for the growth of harmful algal flora. To understand occurrence and distribution of harmful algal blooms species, daily/alternate day samplings were carried out in Mandovi and Zuari estuaries during 2007-2008 and 2008-2009 periods, respectively, comprising of monsoon (June–November) and nonmonsoon (December–May). In Mandovi, total 54 HAB species with 49 in monsoon and 36 during nonmonsoon period were reported. In Zuari, total 46 HAB species with 38 in monsoon and 41 were reported during nonmonsoon period. Bray-Curtis cluster analysis based on log-transformed phytoplankton density detected seven well-defined groups revealing spatiotemporal variability. The density of the dominant harmful algal species was significantly positively correlated with nutrients, but negatively correlated with salinity. The results of the study indicate that monsoon plays an important role in occurrence and distribution of harmful algal species having direct correlation with salinity variations and nutrient loading.

Landscape-level tree diversity assessment in tropical forests of southern Eastern Ghats, India

This large-scale, landscape-level study aims to assess tree species diversity, stem density and stand structure of six major tropical hill forests of southern Eastern Ghats, India, namely, Bodamalai (BM), Chitteri (CH), Kalrayan (KA), Kolli hills (KO), Pachaimalai (PM) and Shervarayan hills (SH). The Eastern Ghats of India is relatively under-studied compared with the Western Ghats biodiversity hotspot. The entire stretch of southern Eastern Ghats was divided into smaller grids of 6.25 km × 6.25 km, totaling to 120 grids. Within each grid, a belt transect of 0.5 ha (5 m × 1000 m) area was laid and all trees ≥30 cm girth at breast height (gbh) were enumerated. A total of 272 tree species (≥30 cm gbh) that belonged to 181 genera and 62 families were recorded in the total 60 ha area inventoried. Diversity indices such as Shannon, Simpson and Fisher's alpha indices were 2.44, 0.03 and 42.1, respectively, for the whole 60 ha area. One way ANOVA revealed that the species richness varied significantly across the six sites ( F (5,823) = 4.854, p < 0.0002). Also, the contribution of tree species to total species richness classified by three plant types viz. evergreen, brevi-deciduous and deciduous species varied significantly across the sites (One way ANOVA: F (2,15) = 10.05, p < 0.002). Similarity indices such as Jaccard and Sørensen showed that sites CH and KA are more similar in terms of species composition. The total stand density and basal area for the total 60 ha area were 27,412 stems (457 stems ha −1) and 1012.12 m 2 (16.9 m 2 ha −1), respectively. The stand density and basal area for the six sites ranged from 290 (in site BM) to 527 stems ha −1 (in site KA) and from 5.6 (in site BM) to 24.4 m 2 ha −1 (in site KO), respectively. Stand density and basal area of tree species varied significantly across the six hill complexes ( F (5,823) = 4.85, p < 0.0002 and F (5,823) = 2.71, p < 0.02, respectively). A positive correlation was obtained between stand density and species richness in sites PM ( r s = 0.65, p < 0.05) and SH ( r s = 0.67, p < 0.05), but not in other sites. The predominant tree species in the tropical forests of southern Eastern Ghats include Albizia amara, Euphorbia antiquorum, Canthium dicoccum var. dicoccum, Memecylon edule, Chloroxylon swietenia and Nothopegia heyneana. Taxonomically, Euphorbiaceae constituted the most diverse family with 25 species. Whereas, by tree abundance the Mimosaceae with 4126 stems enumerated from the 60 ha area formed the dominant family. Bray–Curtis cluster analysis, based on tree species composition and abundance revealed that the low-diverse site BM formed a separate entity from other hill complexes. This large-scale tree diversity inventory provides a baseline data for a variety of investigations and is expected to be useful for effective forest management and biodiversity conservation of southern Eastern Ghats region.

Distinctive patterns in habitat association and distribution of tiger beetles in the Shivalik landscape of North Western India

The purpose of the paper is (a) to describe the distribution pattern of tiger beetles in Shorea robusta dominated forest ecosystems at landscape level of north western Shivalik Himalaya in environmental space and (b) to evaluate the nature of microhabitat association amongst recorded species of tiger beetles. Twenty-five species of tiger beetles belonging to ten genera were recorded from six protected areas in the tropical dry deciduous Shivalik region with an altitudinal gradient of 350–1,400 m above mean sea level in north western India. Sampling for tiger beetles was carried out using strategically designed sample plot in ten distinct habitat types with five collection methods employed. Species composition of tiger beetles varied significantly between microhabitat types of the protected areas (Shannon H′ = 0.436–1.069) and habitat specialists were found in only few of habitats. Bray–Curtis cluster analysis clustered the ten habitats into five cluster groups based upon the species composition with Shorea robusta most distinct from agricultural habitats. Riverine area was found to be the most diverse (with 18 or 72% of total species) as well as abundant (457 ± 33.61 SE individuals recorded per sample plot). Khair, Syzygium and pine forests were least rich and had only three species each. Two species J. crassipalpis and M. melancholica were found only in riverine habitat. Though late summer to mid-monsoon was found most favorable for tiger beetles, only one species, C. chloris was persistently found even during modest winter months. Bulla’s diversity index showed that habitat breadth of species ranged from 0.00 to 6.66, an indicative of their habitat restrictiveness. Indicator species analysis revealed as many as 14 species indicative of particular habitat conditions. Descriptions of some important ecological and behavioral aspects are included for these species. The observed C-score (299.43330) showed that there is less co-occurrence among species pairs alongwith lower niche overlap (Pianka’s index = 0.14191) thereby illustrating ample resource partitioning at microhabitat level. Further, co-occurrence index among guilds (C-score = 213.16250 with variance 1,949.76300) was found to be smaller than expected, revealing that feeding guilds are differing significantly from one another in their levels of co-occurrence. Canonical correspondence analysis identified canopy cover, litter and average tree density as the most important habitat variable defining the distribution of tiger beetles in environmental space. Such assemblage patterns among species of tiger beetle would thus provide a solid basis to interpret changes in microclimatic conditions, caused by humans directly or through long term climate change and would thus help establishing a baseline in long term monitoring of these forest ecosystems.