Vertical distribution and structure of copepod (Arthropoda: Copepoda) assemblages in two different seasons down to 1,200 m in the tropical Southwestern Atlantic

The vertical distribution of copepod assemblages, ascertained from the surface down to 1,200 m, was investigated during two sampling periods (rainy and dry seasons), at four depths, in the oligotrophic waters of the southwestern Atlantic Ocean. Total density, diversity, and richness differed among sampling depths. Copepod density decreased with depth in the two sampling periods, with a maximum at 1 m and a slight decrease at 800 m. Higher diversities were observed at 250 m and 1,200 m during the rainy season and at 1 m and 1,200 m during the dry season. The maximum number of species was found at 1,200 m during the rainy season and at 1 m during the dry season. Various copepod assemblages were delimited in the water column in the two sampling periods. The deeper copepod assemblages occupied a wider range of depths. Salinity and temperature influenced the structure of copepod assemblages and reflected the hydrographic characteristics of the water masses in the region. Candaciapachydactyla (Dana, 1849), Scolecithrixdanae (Lubbock, 1856), and Agetuslimbatus (Brady, 1883) were the indicator species found at 1 m. The effects of different environmental factors on the copepod assemblages suggest that these consortia occupy distinct niches in the ocean.

Download Full-text

Driving forces of the diel distribution of phytoplankton functional groups in a shallow tropical lake (Lake Monte Alegre, Southeast Brazil)

Brazilian Journal of Biology ◽

10.1590/s1519-69842009000100009 ◽

2009 ◽

Vol 69 (1) ◽

pp. 75-85 ◽

Cited By ~ 12

Author(s):

LM. Rangel ◽

LHS. Silva ◽

MS. Arcifa ◽

A. Perticarrari

Keyword(s):

Vertical Distribution ◽

Functional Groups ◽

Rainy Season ◽

Phytoplankton Biomass ◽

Driving Forces ◽

Circulation Pattern ◽

Dry Period ◽

Phytoplankton Functional Groups ◽

The Vertical Distribution ◽

Cool Dry Season

Phytoplankton vertical and diel dynamics in a small shallow lake (Lake Monte Alegre, Ribeirão Preto, state of São Paulo) were investigated in two climatological periods: July 2001 (cool-dry season) and March 2002 (warm-rainy season). Monte Alegre is a eutrophic reservoir, with a warm polymictic discontinuous circulation pattern. The lake was thermally stratified in both periods, although dissolved oxygen varied less in the cool-dry period. Phytoplankton biomass was higher in the warm-rainy season and the vertical distribution was stratified in both seasons. Flagellate groups (Lm, Y, W1 and W2) and functional groups typical of shallow eutrophic environments (J, X1 and Sn) were important throughout the study period. The lake's thermal pattern strongly influenced the vertical distribution of the phytoplankton community in both periods. Biomass, functional groups and size classes of phytoplankton also were determined by the presence of more efficient herbivores in the lake, especially during the cool-dry period when phytoplankton biomass decreased.

Download Full-text

Stable Isotopes Analysis of Precipitation in Subtropical Plateau of Yunnan

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1010-1012.1059 ◽

2014 ◽

Vol 1010-1012 ◽

pp. 1059-1063

Author(s):

Wei Guan ◽

Tao Fan ◽

Xiu Qin Zhu

Keyword(s):

Stable Isotopes ◽

Rainy Season ◽

Mean Value ◽

Dry Season ◽

Precipitation Line ◽

Stable Isotopic ◽

Different Seasons ◽

Geographical Position ◽

The Mean ◽

The Relationship

To elucidate the relationship between stable isotopes of precipitation (SIP) and the extreme drought in Kunming area, based on the stable isotopes data of the GNIP in Kunming site from 1986 to 2003, the precipitation line equation is brought forward and the seasonal change rule of stable isotopes are discussed. The stable isotopic compositions of precipitation exhibit great diversities in different seasons during to influences of multiple factors, such as monsoon, rainfall amount moisture source and others. The δ18O values in rainwater exhibit significant seasonal variations, the average of-10.12‰ in rainy season, the dry season is-4.5‰, having lower values in the rainy season and higher one in the dry season. The amount effect of precipitation is very distinct, that concealed the temperature effect. Got the special geographical position,dvalues present unique characteristics, the average ofdvalues is 10.78‰ in rainy season, and is 4.86‰ in dry season, the mean value is generally lower than most parts of the world.

Download Full-text

Analisis Profil Konsentrasi Pb di Air Waduk Saguling

Jurnal Rekayasa Hijau ◽

10.26760/jrh.v2i3.2509 ◽

2018 ◽

Vol 2 (3) ◽

Author(s):

Ade Arinda ◽

Eka Wardhani

Keyword(s):

Rainy Season ◽

Government Regulation ◽

Water Reservoir ◽

Secondary Data ◽

Quality Standard ◽

Dry Season ◽

Domestic Waste ◽

Water Based ◽

Different Seasons ◽

And Control

ABSTRAKAir Waduk Saguling saat ini menunjukkan penurunan, baik secara kualitas maupun kuantitas akibat aktivitas manusia yang menghasilkan limbah rumah tangga, industri, pertanian, peternakan, perikanan dan pertambangan. Salah satu pencemar di Waduk Saguling adalah logam berat. Penelitian ini bertujuan menganalisis konsentrasi Pb di perairan Waduk Saguling pada musim yang berbeda. Penelitian ini menggunakan data sekunder yang diperoleh dari PT Indonesia Power tahun 2008-2017. Data berasal dari tiga kedalaman yaitu kedalaman permukaan, tengah, dan dekat dasar perairan. Berdasarkan hasil penelitian menunjukkan konsentrasi Pb di musim kemarau lebih tinggi daripada musim hujan dan sebagian sudah melebihi baku mutu yang mengacu pada Peraturan Pemerintah No. 82 Tahun 2001 tentang Pengelolaan Kualitas Air dan Pengendalian Pencemaran Air untuk logam Pb sebesar 0,03 mg/L. Parameter pendukung yang di analisis yaitu parameter DO, pH, TDS, suhu, kekeruhan, dan kesadahan. Berdasarkan hasil analisis statistik menggunakan PCA, parameter yang paling mempengaruhi konsentrasi Pb di musim kemarau adalah kekeruhan dan suhu sedangkan musim hujan adalah TDS.Kata kunci: Musim, Pb, PCA, Waduk SagulingABSTRACTSaguling Water Reservoir currently shows a decline, both in quality and quantity due to human activities that produce domestic waste, industry, agriculture, livestock, fishery and mining. One of the pollutants in Saguling Reservoir is heavy metal. The research aims to analyze the concentration of Pb in the waters of Saguling Reservoir in different seasons. This research uses secondary data which is obtained from PT Indonesia Power in 2008-2017. The data comes from three depths: surface depth, center, and near bottom of water. Based on the results of the research shows that the concentration of Pb in the dry season is higher than the rainy season and some have exceeded the quality standard which refers to Government Regulation no. 82 of 2001 on the Management of Water Quality and Control of Water Pollution for Pb metal by 0.03 mg/L. The supporting parameters in the analysis are DO, pH, TDS, temperature, turbidity, and hardness parameters. Based on the results of statistical analysis using PCA, the parameters that most influence the concentration of Pb heavy metals in the dry season are turbidity and temperature and rainy season is TDS.Keywords: Season, pb, pca, saguling reservoi

Download Full-text

Effects of seasonal variation and locations on microbial load in sediment and water of a polluted ecosystem

Journal of Aquatic Sciences ◽

10.4314/jas.v36i1.9 ◽

2021 ◽

Vol 36 (1) ◽

pp. 93-105

Author(s):

A.N. Okereke ◽

J.C. Ike-Obasi

Keyword(s):

Heterotrophic Bacteria ◽

Standard Procedure ◽

Dry Season ◽

Microbial Load ◽

Seasonal Effects ◽

Wet Season ◽

Different Seasons ◽

Dry Seasons ◽

Total Fungi ◽

Hydrocarbon Utilizing Bacteria

Seasonal effects on microbial load of sediment and water at different locations along Bonny Estuary of Niger Delta was investigated for a period of 12 months. All analyses followed standard procedure. Results revealed that total fungi counts in sediment and water at different locations were not significantly different (p > 0.05) at both wet and dry seasons while hydrocarbon utilizing fungi showed significant differences (p < 0.05) at both seasons in both sediment and water samples. During the wet season, total faecal counts ranged from 5.0 to 10.0 x 105 CFU/g for sediment and 4.0 to 7.0x 105 CFU/g in water. In dry season, the concentration of hydrocarbon utilizing bacteria in the sediment ranged between 0.1 x 105 CFU/ml/g and 8.0 x 105 CFU/ml/g in wet season while in dry season, the concentration in water ranged between 0.1 x 105 CFU/ml/g and 6.0 x 105 CFU/ml/g at Abuloma. At Okwujagu, total heterotrophic bacteria counts in sediment ranged from 0.1 to 8.0 x 105 CFU/g in dry season. This was higher than the range 0.1 to 6.8.0 x 105 CFU/ recorded in Abuloma, Okwujagu and Slaughter at dry season. The highest vibrio counts in water (11.0 x 105 CFU/ml) for wet and (10.0 x 105 CFU/ml) for dry seasons were recorded at Slaughter. In Oginiba, the feacal count recorded 3.0 x 105 CFU/ml in water during the wet season and 2.0 x 105 CFU/ml for dry season. Generally, there were significant differences (p < 0.05) in the bacterial concentrations in both sediment and water. This showed that different seasons favour the growth of certain microbial types.

Download Full-text

The invertebrate colonization during decomposition of Eichhornia azurea kunth in a lateral lake in the mouth zone of Paranapanema River into Jurumirim Reservoir (São Paulo, Brazil)

Brazilian Journal of Biology ◽

10.1590/s1519-69842002000200014 ◽

2002 ◽

Vol 62 (2) ◽

pp. 293-310 ◽

Cited By ~ 21

Author(s):

N. de L. STRIPARI ◽

R. HENRY

Keyword(s):

Decomposition Rate ◽

Rainy Season ◽

Dry Season ◽

Material Loss ◽

Litter Bags ◽

Eichhornia Azurea ◽

Mouth Zone ◽

Dry Seasons ◽

Invertebrate Colonization

The invertebrate colonization during decomposition of Eichhornia azurea was observed in a lateral lake in the mouth zone of Paranapanema River into Jurumirim Reservoir in two periods of the year. The litter bags method was used for measuring the decomposition rate as well as to evaluate the invertebrates colonization. Forty-two litter bags, measuring 15 × 20 cm in size and 2 mm mesh net, were incubated "in situ". Six litter bags (three for colonization and three for decomposition measurements) were removed after the 1st, 3rd, 7th, 14th, 28th, 56th and 72nd days of incubation. After each day, the material was carefully cleaned for detritus removal and invertebrate sampling. The biological material was fixed with 4% formaline and then sorted and identified. The remaining plant material was dried in an oven (at 60ºC) and weighed. A fast material loss occurred during the first 24 hours and the decomposition rate was higher during the rainy season than in the dry season. A peak on invertebrate density (110 ind.g.DW--1) on the remaining detritus of Eichhornia azurea was recorded in the 56th day of dry season, when the polyphenol concentration of plant detritus was 0.57 UDO.g.DW--1. In the rainy season, higher density was found in the 28th day of incubation, when the polyphenol concentration was 4.36 UDO.g.DW--1. Apparently, the reduction in the polyphenol concentration was followed by an increase in invertebrate densities. The majority of the species observed in the detritus belongs to the collector group that was dominant after the 7th and 14th days in the rainy and dry seasons, respectively.

Download Full-text

Characterization of Vietnamese Lacquer Collected in Different Seasons

International Journal of Polymer Science ◽

10.1155/2015/719328 ◽

2015 ◽

Vol 2015 ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

Rong Lu ◽

Kenichiro Anzai ◽

Bach Trong Phuc ◽

Tetsuo Miyakoshi

Keyword(s):

Rainy Season ◽

Laccase Activity ◽

Water Concentration ◽

Dry Season ◽

Composition Analysis ◽

Drying Time ◽

Lipid Component ◽

Different Seasons

Vietnamese lacquers collected every month from June to March of next year were characterized. Composition analysis showed that lacquer collected in rainy season contained much water, while those collected in dry season contained more lipid component. Although hardness of lacquer films is not very hard, lacquers tapped in all seasons can reach hard dry (HD) within 48 hours. Refining lacquer can accelerate drying time but the water concentration should be maintained around 10 wt% for laccase activity.

Download Full-text

The Effect of N in Organic + Inorganic Liquid Fertilizer on the Activity Ability and Antioxidant Properties of Tea Shoots (Camellia sinensis L. O. Kuntze) in the Rainy and Dry Season

Agrologia ◽

10.30598/ajibt.v10i1.1294 ◽

2021 ◽

Vol 10 (1) ◽

Author(s):

Zakarias Frans Mores Hukom

Keyword(s):

Antioxidant Activity ◽

Active Ingredient ◽

Rainy Season ◽

Block Design ◽

Antioxidant Properties ◽

Dry Season ◽

Liquid Fertilizer ◽

Nitrogen Levels ◽

Randomized Block Design ◽

Different Seasons

Antioxidant is a term related to the activity ability and properties of the active ingredient. The higher the ability of the antioxidant activity of an active ingredient, the stronger its antioxidant properties are to ward off various free radical compounds due to oxidative stress. The activity ability and antioxidant properties of tea shoots often fluctuate with changing seasons. This study investigated the effect giving nitrogen levels in organic + inorganic liquid fertilizers on the ability of activity and antioxidant properties of tea shoots in different seasons. The experimental design used was a over season complete randomized block design consisting of 5 levels of fertilization concentration in the rainy and dry seasons. The results showed that the application of organic + inorganic liquid fertilizers without the addition of N concentration in the dry season had a significant effect on the antioxidant activity of tea shoots by 88.14%, and 34.15% higher than control plants in the rainy season and 41.81% more. Height of control plants in the dry season. The IC50 value of tea shoots in the rainy season and dry season has very strong antioxidant properties where the order of the antioxidant properties of the control plants < all concentrations of adding N to organic + inorganic liquid fertilizers < concentration of organic + inorganic liquid fertilizers without the addition of N.Keywords: Ability Antioxidant Activity, Organic + Inorganic Liquid Fertilizer, Tea shoots, Antioxidant Properties.

Download Full-text

Seasonal morphological variability in an in situ Cyanobacteria monoculture: example from a persistent Cylindrospermopsis bloom in Lake Catemaco, Veracruz, Mexico

Journal of Limnology ◽

10.4081/jlimnol.2016.1190 ◽

2016 ◽

Vol 75 (s1) ◽

Cited By ~ 4

Author(s):

Owen Lind ◽

Laura Dávalos-Lind ◽

Carlos López ◽

Martin López ◽

Juli Dyble Bressie

Keyword(s):

Rainy Season ◽

Morphological Variability ◽

Morphological Diversity ◽

Dry Season ◽

Transient Condition ◽

Dry Seasons ◽

Trichome Morphology ◽

Determining Factor

The phrase cyanobacteria bloom implies a transient condition in which one to few species dominates communities. In this paper we describe a condition in which the bloom is of multi-year duration consisting of different morphologies of a single cyanobacteria species. Lake Catemaco, Veracruz, México maintained a year-round massive (108 trichomes L-1) population of potentially toxin-producing cyanobacteria, Cylindrospermopsis spp. The trichomes are present as straight and coiled morphotypes. The relative trichome morphology abundance varied with rainy (June – October) and dry seasons (November – May), but total trichome abundance did not vary. Coiled trichomes and heterocytes (occurring only on coiled trichomes) were significantly more abundant, both absolutely and relatively, during the dry season. Both coiled trichome and heterocyte mean volumes were significantly smaller during the rainy season than during the dry season. Biovolumes were largest in January when water temperature was 5º C cooler suggesting buoyancy as a morphology-determining factor. However, with a more than three-fold lower TIN concentration during the dry season, we hypothesized that the coiled morphotype became abundant primarily because it formed heterocytes, which the straight morphotype did not. Spatial trichome and heterocyte abundance differences were small among the 15 lake sites (average CV for all dates = 20%). However, there was a pattern of increased heterocyte and coiled trichome abundance from lake inflow, as a nitrogen source, to outflow during the rainy season. The total volume of heterocytes per litre of lake water increased progressively four-fold from a minimum early in the rainy season to a maximum at the end of the dry season. Morphological diversity, as seen in Lake Catemaco, can partially compensate for the lack of species diversity in determination of community structure.

Download Full-text

Foraging, nesting and damage caused by Microtermes subhyalinus (Isoptera: Termitidae) in a sugarcane plantation in the Central African Republic

Bulletin of Entomological Research ◽

10.1017/s0007485300034970 ◽

1996 ◽

Vol 86 (4) ◽

pp. 387-395 ◽

Cited By ~ 13

Author(s):

P. Mora ◽

C. Rouland ◽

J. Renoux

Keyword(s):

Vertical Distribution ◽

Linear Relationship ◽

Root System ◽

Central African Republic ◽

Foraging Behaviour ◽

Annual Production ◽

Foraging Activity ◽

Fungus Combs ◽

Different Seasons ◽

The Vertical Distribution

AbstractThe ecology of Microtermes subhyalinus Silvestri in savanna and an adjoining sugarcane plantation in the Central African Republic is described. Other species of termites were associated with savanna and sugarcane but M. subhyalinus was the most prevalent and the only one causing damage to sugarcane. Damage to the crop by M. subhyalinus was assessed throughout the year. Termite attacks were confined initially to the root system just after cutting but as the cane matured and growth ceased, termites tunnelled up into the above-ground stems. Losses accounted for 5–10% of total annual production. The nesting and foraging behaviour of this species altered with the change from natural savanna to sugarcane cultivation. The vertical distribution of M. subhyalinus fungus combs in soil under savanna and sugarcane over different seasons was analysed. There was a linear relationship between monthly rainfall and foraging activity in savanna while in sugarcane no relationship was observed.

Download Full-text

Seasonal morphological variation of the vas deferens of scorpion mud turtle (Kinosternon scorpioides)

Biota Neotropica ◽

10.1590/1676-06032014006413 ◽

2014 ◽

Vol 14 (3) ◽

Cited By ~ 2

Author(s):

Diego Carvalho Viana ◽

Leandro Almeida Rui ◽

Amilton Cesar dos Santos ◽

Maria Angélica Miglino ◽

Antônio Chaves de Assis Neto ◽

...

Keyword(s):

Electron Microscopy ◽

Rainy Season ◽

Vas Deferens ◽

Microscopic Analysis ◽

Lipid Vesicles ◽

Dry Season ◽

Transmission Electron ◽

Cellular Debris ◽

Mud Turtle ◽

Dry Seasons

This study aimed to characterize the morphology of the vas deferens ofKinosteron scorpioides by macroscopic and microscopic analysis. Were used 20 adult male jurarás collected at regular intervals during the year and divided into four experimental groups in the rainy and dry seasons, being processed for light microscopy, scanning electron microscopy and transmission electron microscopy. Morphometry for tubular and luminal diameters and epithelial height were also performed. On rainy season, vas deferens presented pseudostratified epithelium with cylindrical cells, spermatozoids and milky fluid in the lumen, with cytoplasmic organelles and lipid vesicles. On dry season, epithelium was pseudostratified with cuboid cells, with cellular debris and no spermatozoids. There was significant variation (p<0,05) for morphometry of vas deferens, with lower values of tubular and luminal diameters on rainy season, and higher epithelial height on dry season.

Download Full-text