scholarly journals Hydrogeological, hydrochemical, and natural isotopes evaluation of groundwater and surface water interactions in the alluvial plain, tropical region of southeastern Brazil

2021 ◽  
Author(s):  
Waldilene Correa ◽  
Sueli Pereira ◽  
Joaquim Ernesto Bernardes ◽  
Paulo Ricardo Pereira
Keyword(s):  
Surface Water ◽  
Groundwater Flow ◽  
Rainy Season ◽  
Dry Season ◽  
Alluvial Plain ◽  
Morphological Features ◽  
Southeastern Brazil ◽  
Wet Season ◽  
Natural Isotopes ◽  
Abandoned Meanders

Groundwater-Surface water interactions in alluvial plains facing morphological features are the subject of the study. Considered transitions zones, alluvial plains have different morphological features interfering with groundwater flow and hydrochemistry. The alluvial plain of Mogi Guaçu river (southeastern Brazil) presented topography-controlled groundwater flow, nevertheless, natural levees, wet fields, oxbow lakes, and abandoned meanders can control local flow and interfere in discharges points of the main river. Two sampling water campaigns were done in the dry and wet season for physicochemical and natural isotopes analysis, collecting in total 44 groundwaters samples from monitoring wells and eight water samples from the river, creek, and lake. The groundwaters in wet fields and terraces, and surface waters from creek and lake presented low mineralization (EC from 8 to 37 μS.cm), pH acidic (4.98 to 5.8), and essentially Ca and Na-HCO composition. River waters samples presented pH between 5.92 e 7.69 (acidic in the rainy season and basic in the dry season), and EC from 24.2 and 181.1 μS/cm (lower values in the wet season), Na-HCO and Na-HCO-SO (dry season) and Ca-HCO and Na-HCO (rainy season) compositions. In dry season groundwaters composition showed evolution from sodium mixed (SO – HCO) to bicarbonate waters and higher mineralization; in wet season waters varied from Ca to Na-HCO composition and low mineralization, denoting dilution due to rainwater infiltration. Closer to the river margins, in abandoned meanders and oxbows, the groundwaters have increased values of EC and major ions indicating GW-SW mixtures, and effluent-influent changes (descendent and ascendent flux) in wet and dry seasons, respectively. Natural isotopes in groundwaters imply meteoric origin, without evaporation during recharge and high d-excess can be influenced by continental air masses and Amazonia Basin low-level jet. Shallow water table, permeable silty-sand material of vadose zone, flat terrain, and pristine conditions can contribute to direct infiltration of rainwaters, recharging the shallow aquifer.

scholarly journals Characteristics of Surface Water Quality and Diversity of Zoobenthos in Water Bodies, An Giang Province, Vietnam

2021 ◽  
pp. 1-22
Author(s):  
Nguyen T. Giao ◽  
Huynh T.H. Nhien ◽  
Truong H. Dan
Keyword(s):  
Water Quality ◽  
Surface Water ◽  
Rainy Season ◽  
Diversity Index ◽  
Pearson Correlation ◽  
Dry Season ◽  
Water Bodies ◽  
Average Score ◽  
Wet Season ◽  
Wiener Diversity Index

The use of zoobenthos to evaluate water quality has gained considerable interest due to its low cost and environmental friendliness. This study analyzed water and zoobenthos samples at 13 sites in the water bodies in An Giang province in the rainy season (on March) and dry season (on September) in 2018. The results showed that the surface water was contaminated by organic matters, suspended solids and coliforms. There was occurrence of 28 species of zoobenthos divided into five classes including Oligochaeta, Polychaeta, Insecta, Gastropoda, and Bivalvia in which Bivalvia was the most diverse class accounting for 75%. The densities of zoobenthos in the dry and wet season were from 30 divided into three clusters for the dry season and six clusters for the rainy season indicating seasonal variation of zoobenthos composition possibly due to variance of water and sediment characteristics. The results of Pearson correlation indicated that the composition of zoobenthos was strongly correlated with temperature, pH, N-NH4+ and N-NO3-. Using water quality index (WQI), Shannon-Wiener diversity index (H’) and associated average score per taxon (ASPT) for water quality assessment revealed that water quality ranges from medium (from α to β- mesosaprobe) to heavy pollution (Polysaprobe). There was inconsistency between using physicochemicals and diversity index of zoobenthos for water quality identification leading to the use of zoobenthos for water indication could result in misadjustment of water quality. Further study should investigate the relationship between zoobenthos and water quality in different ecological areas to better indicate role of zoobenthos in quick diagnose water quality.

Analyses of groundwater flow and plant evapotranspiration in a vegetated soil slope

2013 ◽  
Vol 50 (12) ◽  
pp. 1204-1218 ◽  
Author(s):  
A.K. Leung ◽  
C.W.W. Ng
Keyword(s):  
Groundwater Flow ◽  
Pore Water Pressure ◽  
Water Pressure ◽  
Three Dimensional ◽  
Root Water Uptake ◽  
Dry Season ◽  
Climatic Data ◽  
Wet Season ◽  
Soil Slopes ◽  
Transient Seepage

Understanding seasonal hydrogeological responses of vegetated soil slopes is vital to slope stability because pore-water pressure (PWP) varies from positive values upon rainfall in wet seasons to negative values upon plant evapotranspiration (ET) in dry seasons. There are, however, few case histories that report seasonal performance of vegetated soil slopes. In this study, a vegetated slope situated in Hong Kong was instrumented to analyse (i) groundwater flow during rainfall in the wet season and (ii) effects of plant ET on PWP in the dry season. Two- and three-dimensional anisotropic transient seepage analyses are conducted to identify groundwater flow mechanism(s) during a heavy rainstorm. Through water and energy balance calculations, measured plant-induced suction is interpreted with plant characteristic and climatic data. During the rainstorm, substantial recharge of the groundwater table was recorded, likely due to preferential water flow along relict joints and three-dimensional cross-slope groundwater flow. During the dry season, the peak suction induced by plant ET is up to 200 kPa and the depth of influence is shallower than 200% of the root depth. For the range of suctions monitored, root-water uptake is revealed to have been restricted by suction not very significantly and was driven mainly by the climatic variation.

scholarly journals Agricultural crops in the diet of bearded capuchin monkeys, Cebus libidinosus Spix (Primates: Cebidae), in forest fragments in southeast Brazil

2008 ◽  
Vol 25 (1) ◽  
pp. 32-39 ◽  
Author(s):  
Carlos Henrique de Freitas ◽  
Eleonore Z. F. Setz ◽  
Alba R. B. Araújo ◽  
Nivar Gobbi
Keyword(s):  
Fruit Production ◽  
Dry Season ◽  
Southeastern Brazil ◽  
Capuchin Monkeys ◽  
Home Ranges ◽  
Forest Fragments ◽  
Wet Season ◽  
Plant Matter ◽  
Wide Range ◽  
Cebus Libidinosus

Capuchin monkeys occupy a wide range of habitats where they feed on fruits, arthropods, and vertebrates. Their large home ranges (80-900 ha) suggest that living in forest fragments may challenge their adaptability. We identified and quantified the main food items of Cebus libidinosus Spix, 1823 in forests fragments (100 ha) in southeastern Brazil. We recorded the feeding activities of two groups using scan sampling over a 13-month period. The diet was composed of fruits, crops, animal prey, seeds, plant matter and undetermined. Fruit was eaten more in the wet season than in the dry season, and maize and sugar cane consumption peaked in the early dry season. The proportion of fruit in the diet was positively correlated with fruiting intensity of zoochorous trees. The plant diet included 54 species, with maize, Rhamnidium elaeocarpus, Acrocomia aculeata, Guazuma ulmifolia and Cariniana, being most important. Although dietary composition and diversity were similar to capuchins in larger forest fragments, feeding on crops attained higher percentages at times when zoochorous fruit production was low in fragments.

scholarly journals Diurnal, Seasonal and Annual Variation of Microwave Radio Refractivity Gradient over Akure, South West Nigeria

2019 ◽  
pp. 1-11
Author(s):  
Adekunle Titus Adediji ◽  
Joseph Babatunde Dada ◽  
Moses Oludare Ajewole
Keyword(s):  
Rainy Season ◽  
Annual Variation ◽  
Ground Surface ◽  
Local Effect ◽  
Dry Season ◽  
Radio Link ◽  
Wet Season ◽  
Annual Variations ◽  
Microwave Radio

In this study, four years in-situ measurements of atmospheric parameters (pressure, temperature and relative humidity) were carried out. The measurement was by placing an automatic weather station at five different heights: ground surface, 50, 100, 150 and 200 m respectively on a 220 m Nigeria Television Authority TV tower in Akure, South Western Nigeria. The four years Data collected (January 2007 to December 2009 and January to December 2011) were used to compute radio refractivity and its gradient. The local effect of a location/ region cannot but looked into when designing effective radio link, hence the diurnal, seasonal and annual variations of the radio refractivity gradient were studied. Results showed that refractivity gradient steadily increases inthe hour of 8:30 and 9:30 to 18:00 during dry season throughout the years investigated, and decreases two hours in the rainy season than the dry season. The record shows that at 50 m altitude, the maximum and minimum values are 158 N-unit/km around 14:30 and - 286 N-unit/km around 13:30 to 14:00 hrs, LT during the dry and rainy season respectively. Seasonally, refractivity gradient is steeper with greater variability in the dry season months than in the wet season months.

scholarly journals Seasonality of Mansonia titillans during dam construction, Biritiba-Mirim, São Paulo State, Brazil

2013 ◽  
Vol 13 (1) ◽  
pp. 70-73 ◽  
Author(s):  
Frederico Alves D'Avila ◽  
Almério de Castro Gomes
Keyword(s):  
Early Spring ◽  
Dry Season ◽  
Southeastern Brazil ◽  
Rank Test ◽  
Late Winter ◽  
Dam Construction ◽  
Wet Season ◽  
Paulo State ◽  
Significant Difference ◽  
Wilcoxon Rank Test

A two and a half year survey was conducted at a dam in southeastern Brazil. Shannon Traps were used for sampling. Kruskal-Wallis test showed little relation between rainfall and abundance. The data clearly show three abundance peaks, all of them in the end of the dry season, in consonance with the scarce literature existent. Although Kruskal-Wallis Test did not find a clear preference for the dry season, Pairwise Wilcoxon Rank Test revealed a significant difference between Fall and Spring samples. Ma. titillans population had a peak on late winter/early spring, close to the begin of wet season.

Seasonal Variation in Bee-Plant Interactions in an Inselberg in the Atlantic Forest in Southeastern Brazil

Sociobiology ◽  
2018 ◽  
Vol 65 (4) ◽  
pp. 612 ◽  
Author(s):  
Marcelita França Marques ◽  
Mariana Scaramussa Deprá ◽  
Maria Cristina Gaglianone
Keyword(s):  
Plant Species ◽  
Atlantic Forest ◽  
Temporal Dynamics ◽  
Interaction Network ◽  
Dry Season ◽  
Floral Resources ◽  
Southeastern Brazil ◽  
Plant Interactions ◽  
Wet Season ◽  
Bee Plant

Studies on bee-plant interactions are relevant to the understanding of temporal patterns in neotropical communities. In isolated habitats such as inselbergs little is yet known about the temporal dynamics in the availability of fl oral resources and interacting bee. In the present study, the objective is to verify the eff ect of seasonality on the bee-plant interaction in an Atlantic Forest inselberg in southeastern Brazil. The bees were sampled monthly in the dry (April/2008-September/2008) and wet seasons (October/2008-March/2009) using an entomological net. A total of 322 bees of 33 species were captured on fl owers of 34 species of plants during the year. Bees richness was similar between seasons (22 species in the wet season and 21 in the dry season), but abundance was higher in the wet season (60% of individuals) and higher diversity occurred in the dry season. Augochloropsis sp1 were the most abundant species and visited the largest number of plant species at each season. In the interaction network, plants with the highest degree were distinct between the seasons. The number of possible interactions was higher in the dry season compared to the wet season and connectance was similar; nestedness however varied between the seasons. The composition of plant and bees species was distinct between the seasons, as well as the interactions between them, mainly due to the alteration in the composition of the plant species and the change in the choice of the bees for the floral resources between the seasons.

scholarly journals Spatial and temporal variability of canopy cover and understory light in a Cerrado of Southern Brazil

2010 ◽  
Vol 70 (1) ◽  
pp. 19-24 ◽  
Author(s):  
JP. Lemos-Filho ◽  
CFA. Barros ◽  
GPM. Dantas ◽  
LG. Dias ◽  
RS. Mendes
Keyword(s):  
Rainy Season ◽  
Light Availability ◽  
Canopy Cover ◽  
Dry Season ◽  
Photon Flux ◽  
Photon Flux Density ◽  
Spatial And Temporal Variability ◽  
Wet Season ◽  
Area Index ◽  
Understory Plants

Canopy cover has significant effects on the understory environment, including upon light availability for seedling growth. The aim of the present study was to verify spatial heterogeneity and seasonal changes in the canopy cover of a dense Cerrado area, and their relationship to understory photosynthetic active radiation availability. Leaf area index (LAI) values in the rainy season varied from 0.9 to 4.83, with 40% of the values ranging from 4.0 to 5.0, while in the dry season LAI varied from 0.74 to 3.3, with 53% of the values oscilating from 2.0 to 3.0. Understory light (Qi ) and the Lambert-Beer ratio (Qi/Qo) were taken around noon on sunny days (between 11:00 AM and 1:00 PM). They were also statistically different (p < 0.01) between the dry and wet seasons, with 72% of sampled points in the rainy season presenting photosynthetic photon flux density (PPFD) values lower than 250 μmol.m-2/s around noon, whereas in the dry season, most PPFD values varied from 1500 to 1817 μmol.m-2/s , thus providing high light availability for understory plants. In most of the studied sites, understory plants did not even receive enough light for 50% of their photosynthetic capacity in the wet season. In contrast during the dry season, Qi/Qo values of 0.8 to 1.0 were observed in more than 50% of the points, thereby allowing for photosynthetic light saturation. Thus, light variability around noon was higher during the dry season than in the wet season, its heterogeneity being related to spatial complexity in the canopy cover.

Study on the Contamination of NH3-N and Total Phosphorus in the Seasonal River

2013 ◽  
Vol 864-867 ◽  
pp. 79-82
Author(s):  
Xue Ying Song ◽  
Xiao Jun Hu ◽  
Ru Jing Liang ◽  
Yu Shuang Liang ◽  
Wen Juan Sun
Keyword(s):  
Surface Water ◽  
Total Phosphorus ◽  
Industrial Wastewater ◽  
Quality Standards ◽  
Domestic Sewage ◽  
Dry Season ◽  
Main Stream ◽  
Wet Season ◽  
Permissible Levels ◽  
Taizi River

Water samples were collected from the upstream to the downstream of a seasonal river, the Taizi River, and its main tributaries in dry season, normal season, and wet season. The variations of NH3-N, and total phosphorus (TP) within a hydrological year were analyzed, aimed to study the pollution characteristics and sources of the water bodies. It was found that the tributaries of the Taizi River were heavily contaminated by NH3-N, with 83.8%, 100% and 100% of the sampling sites exceeding the fifth level in the dry season, wet season and normal season, respectively. The concentration of TP in the dry season fluctuated wildly, which was much higher than those in the wet and normal season. Compared with the permissible levels set by the environmental quality standards for surface water standard (GB3838-2002) of China, 57.1% of the sampling sites in the main stream and tributaries of the Taizi River belong to the fifth level or exceed the fifth level in the dry season, and only 7.1% of the sampling sites were belonging to the fifth level or exceed the fifth level in the wet and normal season. Overall, the waterbody of Taizi River was more seriously polluted by urban domestic sewage and point source of industrial wastewater.

scholarly journals The Corrosivity Level of Rawa Pening Downstream Surface Water in the Dry and Rainy Season

2020 ◽  
Vol 17 (3) ◽  
pp. 215-222
Author(s):  
Purwono Purwono ◽  
Wiharyanto Oktiawan ◽  
Titik Istirokhatun ◽  
Agus Nurfaiz
Keyword(s):  
Surface Water ◽  
Rainy Season ◽  
Agricultural Land ◽  
Ph Value ◽  
Dry Season ◽  
Hydroelectric Power ◽  
Geological Material ◽  
Measurement Results ◽  
Microbiological Parameters

Corrosion is an important factor that can affect the quality of air used by humans. This has an impact on health and economic factors, damage to air distribution equipment. The level of corrosivity of surface water as raw water for drinking water is important to be examined before the water enters the processing process or other uses such as hydroelectric power (PLTA). This study aims to measure the level of water corrosivity on the surface of the Pening swamp during the dry and rainy seasons in 2018. Taking air samples on the surface of the Pening swamp, then carrying out laboratory tests on the parameters of air corrosivity. The results showed that the downstream surface of the Pening swamp was not corrosive in terms of pH, temperature, TDS, and chloride parameters. The pH value in the dry season (J1) is 7.00, while in the rainy (J2) it is 7.77 and is non-corrosive. The temperature values are 28.6oC and 29.3oC in the rainy and dry seasons, respectively. The TDS measurement results in the dry season are lower than the rainy season by a difference of 12 mg / l. In the dry season it is 141 mg / l and the rainy season is 153 mg / l. This increase probably came from geological material (geological material) such as rocks and soil around the Pening Swamp Lake. Other sources of TDS include urban land, road workers, agricultural land and pasture. Human activities also increase in the increase of TDS in water including domestic activities (bathing and washing), trade, and industry. Chloride levels were 2.19 mg / l and 3.19 mg / l. This research has implications for the users of Sungai Pening Swamp. The corrosivity of air measurement is also by microbiological parameters which need to be investigated further.

Seed-dispersing bird assemblages in riparian environments of a partially urbanized river basin, Southeastern Brazil

2020 ◽  
Author(s):  
B. F. Lessi ◽  
M. G. Reis ◽  
C. Z. Fieker ◽  
M. M. Dias
Keyword(s):  
Ecosystem Services ◽  
Seed Dispersal ◽  
Bird Species ◽  
Dry Season ◽  
Ecosystem Dynamics ◽  
Southeastern Brazil ◽  
Wet Season ◽  
Frugivorous Birds ◽  
Entire Area ◽  
Number Of Individuals

Abstract Birds play a key role in ecosystem dynamics, including urban and rural areas, bringing environmental quality improvements and ecological stability. Species contribute directly to natural regeneration of vegetation and succession processes, by offering ecosystem services as seed dispersal, an important role in human-modified areas. We studied the assemblages of fruit-eating birds in riparian environments of Monjolinho basin, central São Paulo state, southeastern Brazil. Birds were recorded in 41 points distributed in riparian ecosystems alongside waterbodies, in landscapes with five types of surrounding matrices: urban, periurban, farmland, and native vegetation. We described how assemblages are structured aiming to evaluate the possible influence of seasonality and landscape type. We recorded 39 bird species that can play a role as seed-dispersers, 32 in wet season and 32 in dry season. There were no significant differences in the diversity and dominance of species between seasons considering the entire area, indicating stability of basic assemblage structure. However, total number of individuals of all species recorded in different landscapes were influenced by seasonality. Also, the composition and abundance of species significantly changed between seasons, leading to a high dissimilarity with almost 50% of the species contributing with almost 90% of the observed variation. A higher taxonomic diversity and distinctness pointed to a wider array of possible seed dispersal services in natural areas, while the lowest values of indexes were found in human-modified areas. The higher number of non-related bird species during dry season contrasted with the higher number of individuals during wet season, indicating that there is more possible ecosystem services offered by frugivorous birds in driest period of the year, while in the rainy period the carrying capacity of the riparian environments was increased.

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