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1

Vargas-Sánchez, Mariana, Javier Alcocer, and Luis A. Oseguera. "Seston and eutrophication on a tropical karst lake district: Lagunas de Montebello, Chiapas, Mexico." Limnetica 41, no. 2 (June 15, 2022): 1. http://dx.doi.org/10.23818/limn.41.16.

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Large quantities of seston are among the most important indicators of eutrophication in aquatic ecosystems. The present study aimed to elucidate the role seston plays in the general limnological dynamics of a cluster of eighteen tropical karstic lakes with different anthropic impacts (non-impacted, oligotrophic, clear-water lakes, and impacted, eutrophic, turbid-water lakes) of the “Lagunas de Montebello” National Park lake district. The seston concentration was measured twice, in the warm/rainy and the cold/dry season. Vertical profiles of temperature, dissolved oxygen, electrical conductivity, pH, and photosynthetic active radiation (PAR) were recorded at each lake. Water samples were taken along the water column to evaluate seston and chlorophyll a (Chl-a) concentration. Impacted lakes displayed higher seston (4.1-21.0 mg/L) and Chl-a (8.1-129.8 μg/L) concentrations, reduced euphotic zone (ZEU = 2.6-6.3 m), and superficial thermo- (gradient = 0.8 ± 0.2 °C/m) and oxyclines (gradient = 4.7 ± 2.4 mg DO/m). Non-impacted lakes had lower seston (1.0-2.1 mg/L) and Chl-a (0.4-5.2 μg/L) concentrations, wide ZEU (10.1-33.4 m), and deeper thermo- (gradient = 0.5 ± 0.1 °C/m) and oxyclines (gradient = 0.6 ± 0.4 mg DO/m). The changes reported in impacted lakes linked with the increase in the seston and Chl-a concentrations are most likely related to the eutrophication process asso¬ciated with anthropogenic activities (agriculture, urban development, land-use change) in the NW part of the area. This research highlights the fragility of the tropical karst lake ecosystems worth protecting to preserve the aquatic ecosystem’s health.
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2

-, Arhananta, Sari Bahagiarti Kusumayudha, and Agus Harjanto -. "PENGARUH LITOLOGI DAN STRUKTUR GEOLOGI TERHADAP AIR TANAH DI DAERAH WEDIOMBO, KECAMATAN GIRISUBO, KABUPATEN GUNUNGKIDUL, PROVINSI DAERAH ISTIMEWA YOGYAKARTA." Jurnal Sumberdaya Bumi Berkelanjutan (SEMITAN) 1, no. 1 (July 19, 2022): 13–24. http://dx.doi.org/10.31284/j.semitan.2022.3064.

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Daerah penelitian secara administratif berada pada Desa Jepitu, Desa Karangawen, Desa Tileng, Desa Balong, Desa Purwodadi, dan Desa Tepus, Kecamatan Girisubo, Kabupaten Gunungkidul, Provinsi Daerah Istimewa Yogyakarta. Metode yang digunakan dalam penelitian ini terdiri atas pemetaan geologi permukaan, Measuring Section (MS), pemetaan hidrogeologi, dan pengambilan conto batuan serta air tanah. Arah aliran air bawah tanah sepanjang teluk Wediombo dipengaruhi oleh sesar mendatar orde 1, dengan arah aliran yang berarah tenggara pada sisi barat dan berarah barat daya pada sisi timur. Pada bagian tengah, arah aliran air bawah tanah ke selatan dipengaruhi oleh sesar orde 2 (Sesar Pokgunung). Batugamping memengaruhi tingginya unsur Ca2+, HCO3-, dan CO32- pada air tanah. Lava lapuk (teralterasi) memengaruhi tingginya unsur Mg2+, Na+, K+, dan Cl- pada air tanah. Kontak breksi-batugamping memengaruhi tingginya unsur Mg2+, Na+, dan Cl- pada air tanah. Batugamping memengaruhi tingginya nilai daya hantar listrik, dan kekeruhan, serta dicirikan dengan debit yang tinggi. Lava segar dan kontak breksi-batugamping memengaruhi rendahnya nilai pH air tanah
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3

Surbakti, Amsal Frans Harapenta, Anju Goldmoreast Marbun, and Sendita Aditya. "Kontrol Struktur Geologi Terhadap Potensi Panas Bumi Daerah Danau Ranau, Sumatera Selatan dan Sekitarnya." Dinamika Rekayasa 18, no. 1 (January 20, 2022): 63. http://dx.doi.org/10.20884/1.dr.2022.18.1.445.

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<p>Reduksi ketersediaan energi konvensional menuntut pengembangan energi alternatif, salah satunya panas bumi. Danau Ranau memiliki potensi panas bumi direpresentasikan dengan manifestasi mata air panas di permukaan. Sasaran identifikasi awal potensi panas bumi terkait asosiasinya dengan struktur rekahan dan patahan. Observasi ini dikembangkan dengan studi pustaka, penginderaan jauh dengan pendekatan melalui satelit citra, survei manifestasi, dan analisis studio. Berdasarkan analisis ini didapati pola kelurusan dominan barat laut – tenggara dan dipengaruhi oleh gaya kompresi dengan arah relatif utara – selatan. Pola kelurusan ini berasosiasi dengan struktur geologi sebagai <em>play zone </em>dari reservoir <em>geothermal</em>. Tipe kelurusan juga diinterpretasikan bahwa Danau Ranau merupakan <em>discharge zone </em>yang dihasilkan oleh sesar mendatar yaitu Sesar Kumering dengan pola serupa Sesar Semangko. Hasil survei permukaan ditemukan dua lokasi manifestasi Air Panas Ranau (APR) dan Air Panas Lumbok (APL). Lokasi APR ditemukan dua titik manifestasi dengan suhu sekitar 54<sup>o </sup>C dan 60<sup>o </sup>C, kadar pH netral, dan litologi penyusun batuan sampingnya berupa endapan piroklastik yaitu <em>welded tuff </em>dan batuan beku andesit. Pada APL terdapat dua titik manifestasi air panas dengan suhu sekitar 45<sup>o </sup>C hingga 59<sup>o </sup>C dengan pH relatif netral. Potensi energi sekitar 37 Mwe diduga terdapat pada reservoir panas bumi pada daerah Danau Ranau</p>
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4

Wahyu, Syafrima, Yunus Daud, Tony Rahadinata, and Sari Sekar Ningrum. "Identifikasi Potensi Sistem Panasbumi Berdasarkan Korelasi Data Geologi Dan Data Gravitasi Dengan Menggunakan Teknik Filtering First Horizontal Derivative (FHD) - Second Horizontal Derivatif (SVD)." Jurnal Teknologi 7, no. 1 (November 30, 2019): 40–53. http://dx.doi.org/10.31479/jtek.v7i1.37.

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Daerah panasbumi “Z” dalam tatanan tektoniknya termasuk pada jalur back-arc Sumatera, tepat pada salah satu segmen sesar Sumatera bagian selatan, disusun oleh batuan vulkanik dan sedimen klastik yang berumur Tersier hingga Kuarter (Andesit-Basalt). Gejala adanya potensi sistem panasbumi pada daerah penelitian ditandai dengan kemunculan manifestasi permukaan berupa alterasi dan lima mata air panas bersuhu 44,4 – 92,5 oC dan pH antara 8,19 – 9,43. Pengolahan Data gravitasi menggunakan teknik pemisahan Complete Bouguer Anomali (CBA), filtering First Horizontal Derivative (FHD) dan filtering Second Vertical Derivative (SVD) untuk mengetahui kemungkinan lokasi sumber panas dan letak bidang kontak terjadinya anomali serta jenis sesarnya. Berdasarkan slicing lintasan FHD dan SVD, struktur pada peta geologi didominasi oleh sesar naik dan sesar normal yang bersifat regional, serta struktur dengan kompleksitas tinggi yang bersifat lokal. Kemunculan manifestasi permukaan sistem panasbumi berada disekitar nilai anomali residual gravitasi tinggi (8 – 24 mgal) yang mengindikasikan terdapatnya batuan yang kompak dan massif. Diperkirakan sistem panasbumi daerah penelitian termasuk jenis tektonik fracture zone serta anomali tinggi yang berada di sekitar APZ1-APZ2-APZ3 tersebut terdapat batuan intrusi yang berperan penting sebagai sumber panas.
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5

Permana, Hanif Aditya, Fikra Titan Syifa, and Mas Aly Afandi. "Sistem Monitoring pH dan Kekeruhan Akuarium Menggunakan Metode Regresi Linear." Journal of Telecommunication, Electronics, and Control Engineering (JTECE) 4, no. 1 (June 2, 2022): 47–55. http://dx.doi.org/10.20895/jtece.v4i1.407.

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Pada pemeliharaan ikan didalam akuarium membutuhkan perawatan guna menjaga kelangsungan hidup ikan dan vegetasi air yang terdapat didalamnya. Selain rutinitas pemberian pakan, nilai parameter lingkungan akuarium juga perlu selalu diawasi dan dijaga pada rentang tertentu. Tujuan utama yang ingin dicapai untuk memonitoring pH dan kekeruhan pada akuarium sehingga kualitas air akuarium bisa terjaga. pH yang baik untuk ikan hias di akuarium yaitu lebih dari 7 dan kurang dari 8, kemudian kekeruhan yang baik untuk ikan hias di akuarium yaitu dibawah 25 ntu. Pada penelitian ini menggunakan mikrokontroler NodeMCU ESP32 digunakan sebagai pusat kendali sistem, kemudian sensor pH untuk mendeteksi nilai pH air, kem Pada pemeliharaan ikan didalam akuarium membutuhkan perawatan guna menjaga kelangsungan hidup ikan dan vegetasi air yang terdapat didalamnya. Selain rutinitas pemberian pakan, nilai parameter lingkungan akuarium juga perlu selalu diawasi dan dijaga pada rentang tertentu. Tujuan utama yang ingin dicapai untuk memonitoring pH dan kekeruhan pada akuarium sehingga kualitas air akuarium bisa terjaga. pH yang baik untuk ikan hias di akuarium yaitu lebih dari 7 dan kurang dari 8, kemudian kekeruhan yang baik untuk ikan hias di akuarium yaitu dibawah 25 ntu. Pada penelitian ini menggunakan mikrokontroler NodeMCU ESP32 digunakan sebagai pusat kendali sistem, kemudian sensor pH untuk mendeteksi nilai pH air, kemudian sensor turbidity untuk mendeteksi nilai kekeruhan air, kemudian Buzzer berfungsi sebagai alarm dan yang terakhir LCD berfungsi untuk menampilkan hasil dari pembacaan sensor tersebut. Pada penelitian ini metode yang digunakan yaitu metode regresi linear untuk mengetahui keakuratan dari pembacaan sensor pH. Pada penelitian ini terdapat pengujian sensor turbidity untuk menguji hasil sensor, pengujian sensor pH untuk menguji nilai ADC / tegangan output dan akurasi sesnsor pH, Pengujian regresi linear pada sensor pH dan pengujian QOS untuk mengetahui beberapa nilai parameter diantara lain delay, throughput, packet loss dan jitter. Pada sistem ini digunakan android ntuk monitoring dan notifikasi dengan implementasi internet of things. Berdasarkan hasil pengujian pada sensor pH dengan kondisi pH 4,2, 7,1 dan 9,4, pada pembacaan sensor dengan kondisi pH 9,4 tingkat rata-rata errornya yaitu 2%. Namun setelah diuji denngan metode regresi linier dengan persamaan y=-0,2540+1,0468X nilai rata-rata errornya menjadi 0%, dapat disimpulkan bahwa metode regresi linier dapat diterpakan pada penelitian ini. Pada hasil pengujian QOS delay didapatkan nilai rata-rata pengujian delay sebesar 975,9470 ms dimana termasuk dalam kategori jelek, packet loss didapatkan rata-rata sebesar 15,126 % dimana termasuk dalam kategori sedang, throughput didapatkan rata-rata sebesar 694,661 bit/s dimana termasuk dalam kategori sangat bagus dan Jitter didapatkan rata-rata sebesar 473,9918 ms dimana masuk dalam kategori jelek. Kata kunci : Akuarium, Sensor pH, Sensor Turbidity, NodeMCU ESP32, Buzzer, LCD.
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6

Špoljar, Maria, Tvrtko Dražina, Ana Ostojić, Marko Miliša, Marija Gligora Udovič, and Dagmar Štafa. "Bryophyte communities and seston in a karst stream (Jankovac Stream, Papuk Nature Park, Croatia)." Annales de Limnologie - International Journal of Limnology 48, no. 1 (2012): 125–38. http://dx.doi.org/10.1051/limn/2011057.

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An investigation into bryophyte communities in karst Jankovac Stream (Papuk Nature Park, Croatia) was carried out once a month from July 2008 to June 2009. Samples were taken from two lotic microhabitats: (i) Jankovac Spring (JS), a hypocrenal habitat with dense bryophyte clusters (90% bottom cover) and (ii) Jankovac Waterfall (JW), with scattered bryophyte clusters (50% bottom cover). At the same time, seston samples were collected during the spring as the source site and after the JW, as the outflow site. The goals of this study were to understand the (i) algal, protozoan and metazoan bryophyte community assemblages in these two lotic microhabitats, (ii) influence of environmental factors on the structuring of the bryophyte community and (iii) structure of seston along the longitudinal profile. A total of 172 taxa were determined: 68 algae, 55 protozoa, 24 meiofauna and 25 macroinvertebrates. Statistically significant differences between two microhabitats differing in percentage of bryophyte cover were established testing 13 environmental parameters. In dense bryophyte clusters, community structure was determined by flow velocity and pH, and macroinvertebrates achieved higher diversity and abundance. On the contrary, in scattered bryophyte coverage algae, protozoa and meiofauna reached higher abundance and diversity governed by the amount of suspended organic matter and epiphyton. In contrast to previous studies, the inverse ratio of community diversity and abundanceversuspercentage of bryophyte cover was established. We assume this to be the result of an enrichment of the scattered bryophyte clusters by upstream seston. Additionally, the effects of anthropogenic hydromorphological disturbance are reflected in macroinvertebrate diversity and abundance reduction.
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7

Rocha, RRA, SM Thomaz, P. Carvalho, and LC Gomes. "Modeling chlorophyll-a and dissolved oxygen concentration in tropical floodplain lakes (Paraná River , Brazil)." Brazilian Journal of Biology 69, no. 2 suppl (June 2009): 491–500. http://dx.doi.org/10.1590/s1519-69842009000300005.

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The need for prediction is widely recognized in limnology. In this study, data from 25 lakes of the Upper Paraná River floodplain were used to build models to predict chlorophyll-a and dissolved oxygen concentrations. Akaike's information criterion (AIC) was used as a criterion for model selection. Models were validated with independent data obtained in the same lakes in 2001. Predictor variables that significantly explained chlorophyll-a concentration were pH, electrical conductivity, total seston (positive correlation) and nitrate (negative correlation). This model explained 52% of chlorophyll variability. Variables that significantly explained dissolved oxygen concentration were pH, lake area and nitrate (all positive correlations); water temperature and electrical conductivity were negatively correlated with oxygen. This model explained 54% of oxygen variability. Validation with independent data showed that both models had the potential to predict algal biomass and dissolved oxygen concentration in these lakes. These findings suggest that multiple regression models are valuable and practical tools for understanding the dynamics of ecosystems and that predictive limnology may still be considered a powerful approach in aquatic ecology.
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8

Marques Júnior, Aguinaldo Nepomuceno, Mirian Araujo Carlos Crapez, and Conceição Denise Nunes Barboza. "Impact of the Icaraí Sewage Outfall in Guanabara Bay, Brazil." Brazilian Archives of Biology and Technology 49, no. 4 (July 2006): 643–50. http://dx.doi.org/10.1590/s1516-89132006000500014.

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The present study aimed to evaluate the water quality of the Icaraí Sewage Outfall (ISEO) area. Sampling was conducted during winter and summer, and water samples were analyzed for dissolved oxygen, pH, temperature, salinity, dissolved inorganic nutrients (DIN), seston, particulate organic matter (POM), and pigments. Results showed that the water chemistry of the area suffers temporal and spatial variation. Great variability was also seen in the C:N:P ratios of POM (August, 112:30:1; December, 59:11:1) and in the DIN concentrations. Chlorophyll-a and ammonium concentrations (4.5 µg L-1 - 71.2 µg L-1, and 0.20 µM - 52,6 µM, respectively) characterized the ISEO area as eutrophic. The dispersal of the material was not effective under certain oceanographic conditions.
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Bermúdez, Rafael, Monika Winder, Annegret Stuhr, Anna-Karin Almén, Jonna Engström-Öst, and Ulf Riebesell. "Effect of ocean acidification on the structure and fatty acid composition of a natural plankton community in the Baltic Sea." Biogeosciences 13, no. 24 (December 16, 2016): 6625–35. http://dx.doi.org/10.5194/bg-13-6625-2016.

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Abstract. Increasing atmospheric carbon dioxide (CO2) is changing seawater chemistry towards reduced pH, which affects various properties of marine organisms. Coastal and brackish water communities are expected to be less affected by ocean acidification (OA) as these communities are typically adapted to high fluctuations in CO2 and pH. Here we investigate the response of a coastal brackish water plankton community to increasing CO2 levels as projected for the coming decades and the end of this century in terms of community and biochemical fatty acid (FA) composition. A Baltic Sea plankton community was enclosed in a set of offshore mesocosms and subjected to a CO2 gradient ranging from natural concentrations ( ∼ 347 µatm fCO2) up to values projected for the year 2100 ( ∼ 1333 µatm fCO2). We show that the phytoplankton community composition was resilient to CO2 and did not diverge between the treatments. Seston FA composition was influenced by community composition, which in turn was driven by silicate and phosphate limitation in the mesocosms and showed no difference between the CO2 treatments. These results suggest that CO2 effects are dampened in coastal communities that already experience high natural fluctuations in pCO2. Although this coastal plankton community was tolerant of high pCO2 levels, hypoxia and CO2 uptake by the sea can aggravate acidification and may lead to pH changes outside the currently experienced range for coastal organisms.
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10

Rada, Ronald G., David E. Powell, and James G. Wiener. "Whole-Lake Burdens and Spatial Distribution of Mercury in Surficial Sediments in Wisconsin Seepage Lakes." Canadian Journal of Fisheries and Aquatic Sciences 50, no. 4 (April 1, 1993): 865–73. http://dx.doi.org/10.1139/f93-099.

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We quantified total mercury in surficial sediments (uppermost 5 cm) of six small seepage lakes. Fifty cores were taken from each lake, based on a random sampling design stratified by water depth. Volumetric concentrations (mass per volume of wet sediment) more accurately portrayed the depth distribution of mercury in the lakes than did dry-weight concentrations, which underrepresented the significance of the shallow-water sediments as a reservoir of potentially available mercury. Estimates of whole-lake burdens (masses) of mercury in the surficial sediment, which represent the maximum amount of sedimentary mercury available for methylation, ranged from 45 to 149 g. These sedimentary pools of mercury greatly exceeded the inventories of the metal in water, seston, and fish, and the release of mercury from the sediments could significantly increase its bioaccumulation. Areal burdens of mercury (mass per unit of lake area) varied fivefold among lakes (1.65–7.84 g/ha) and were strongly correlated with lake pH, but were not correlated with dissolved organic carbon, conductance, or chlorophyll a of lakes. We hypothesize that the observed variation in areal burdens of mercury was partly due to variation among lakes in the pH-related efflux of gaseous mercury (Hg0) from the lakes to the atmosphere.
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11

Morrison, Kenneth A., and Carl J. Watras. "Mercury and methyl mercury in freshwater seston: direct determination at picogram per litre levels by dual filtration." Canadian Journal of Fisheries and Aquatic Sciences 56, no. 5 (May 1, 1999): 760–66. http://dx.doi.org/10.1139/f99-029.

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Here, we describe a method for directly determining sestonic mercury in lake waters at concentrations ranging down to 0.12 ng Hg/L (total Hg) and 0.01 ng MeHg/L (monomethyl mercury) in a 250-mL water sample. Detection limits for the method are 30 pg of Hg and 3.0 pg of MeHg, reported as three times the standard deviation of a procedural blank. The method involves dual filtration using ultraclean 47-mm-diameter, 0.45-µm pore size cellulose nitrate filters in an all-Teflon® filter stack. Lake water is pumped directly through a primary filter that traps suspended seston particles and then through a secondary filter that is used to estimate the integrated reagent, filter, and sorption blank. Both filters are analyzed for Hg or MeHg and the primary filter is corrected by subtracting the secondary blank. Sestonic Hg is determined after acid digestion and wet oxidation of the filters with BrCl, reduction with NH2OH-HCl followed by SnCl2, and purging via N2 onto dual gold traps for detection via cold-vapor atomic fluorescence spectroscopy. Sestonic MeHg is determined after acid distillation of the filters, aqueous-phase ethylation, purging onto Tenax®, isothermal gas chromatography separation, and detection by cold-vapor atomic fluorescence spectroscopy. The method was tested on a variety of lakes in Wisconsin, Florida, and Washington. The blank-corrected mass of sestonic mercury collected from these lakes onto primary filters ranged from 30 to 340 pg Hg and from 3 to 23 pg MeHg. The corresponding concentrations of mercury in the seston were 22-790 ng Hg/g dry weight and 3-75 ng MeHg/g dry weight. The method allowed us to demonstrate a clear negative dependence of sestonic mercury concentrations (weight:weight) on pH in Wisconsin lakes.
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12

Kolm, Hedda Elisabeth, Maria Fernanda Schoenenberger, Mariana da Rocha Piemonte, Patrícia S. de A. Souza, Guilherme Schnell e. Scühli, Mariele B. Mucciatto, and Roseli Mazzuco. "Spatial Variation of Bacteria in Surface Waters of Paranaguá and Antonina Bays, Paraná, Brazil." Brazilian Archives of Biology and Technology 45, no. 1 (March 2002): 27–34. http://dx.doi.org/10.1590/s1516-89132002000100005.

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Spatial variability in the concentration of total bacteria, saprophytes and coliforms abundance was investigated in surface waters of Paranaguá and Antonina Bays. Six points along a profile from the entrance of Paranaguá Bay to the innermost part of Antonina Bay, were sampled on February 26, 1997. Temperature, salinity, dissolved oxygen, pH, particulate organic carbon, water transparency and seston were also measured. Determination of total bacterial abundance and biomass were made with the epifluorescent method. Saprophytic bacteria counts were conducted with ZoBell 2216E culture medium with fresh and 32‰ water and the coliform MPN was enumerated with the chromogenic substrate method. Principal component analysis of biotic and abiotic data showed a gradient from the innermost bay to the baymouth bar with an increase in total and halophobic aerobic cultivated bacteria concentration at Antonina Bay. Greatest values of halophilic aerobic cultivated bacteria were found at the bay’s middle part. The greatest fecal coliform number was observed near Paranaguá City. We concluded that regarding bacterial spatial distribution the outer region of the estuary was highly influenced by the adjacent ocean and that the inner part had typical estuarine characteristics.
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Arnanz, Christian, Ana Isabel López-Archilla, and Paloma Alcorlo. "Ecological impact of recreational bathing at Las Presillas (Lozoya River, Sierra de Guadarrama National Park, central Spain)." Limnetica 41, no. 2 (June 15, 2022): 1. http://dx.doi.org/10.23818/limn.41.23.

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The ecological impacts of recreational uses on the rivers of Sierra de Guadarrama National Park (SGNP) have been scarcely studied. To assess the impacts of these uses at Las Presillas (an area with small dam along a section of the Lozoya River), and in the Lozoya River (upstream and downstream of the dams), the dynamics of the organic seston (FPOM), physicochemical variables (electric conductivity, dissolved oxygen, Temperature, and pH) and biological variables (fecal coliforms, fecal streptococci, and aquatic macroinvertebrates) during the recreational (July to September) and nonrecreational (October) periods were assessed. The variations observed in the physicochemical parameters were associated with autumnal influence. However, at Las Presillas, different values were found than at the rest of the surveyed sites, characterized by an increase in the concentration of FPOM and, human fecal contamination (although they did not reach dangerous levels) and the response of the macroinvertebrate communities, which resulted in a clear decrease in the IBMWP index and other quality metrics, during the recreational period. These findings suggest that the combined effects of the dams and recreational activities at Las Presillas generate functional dynamics in that alter the habitat in summer. The identification and study of these impacts through the application of innovative indices and quality classes that integrate and contextualize Las Presillas in the SGNP monitoring network, have been identified as key management and conservation tools.
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Cordeiro, Giovanna Gomes, Nathália De Macêdo Guedes, Tiago Borges Kisaka, and Gabriela Bielefeld Nardoto. "Avaliação rápida da integridade ecológica em riachos urbanos na bacia do rio Corumbá no Centro-Oeste do Brasil." Ambiente e Agua - An Interdisciplinary Journal of Applied Science 11, no. 3 (June 23, 2016): 702. http://dx.doi.org/10.4136/ambi-agua.1857.

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A urbanização tem ocasionado o lançamento de volumes significativos de efluentes domésticos parcialmente tratados nos corpos hídricos brasileiros causando diversos prejuízos ecológicos para estes ecossistemas. Para avaliar a integridade ecológica de riachos na região de Cerrado do Brasil Central foram selecionados quatro pontos de coleta, considerando o nível de influência antrópica ao qual estão submetidos. Foram analisados parâmetros físicos e químicos da água, o uso da paisagem e a comunidade de macroinvetebrados bentônicos. As coletas foram realizadas em julho de 2015 e foram mensuradas “in situ” as variáveis condutividade elétrica, temperatura da água, pH, oxigênio dissolvido, turbidez, largura e comprimento do riacho e velocidade da correnteza. Em seguida, foram coletadas amostras para o seston, perifíton, macroinvertebrados bentônicos e sedimento depositado. O ponto “Referência” apresentou menor abundância de larvas de Chironomus (Chironomidae: Diptera) e maior riqueza taxonômica, além de maior abundância dos grupos taxonômicos Ephemeroptera, Plecoptera e Trichoptera, mostrando ser o sistema mais íntegro dentre os analisados. A sub-bacia delimitada a partir desse ponto mostrou uma maior porcentagem de áreas com vegetação nativa (51%). Os pontos com presença de efluentes domésticos (“ETE” e “Jusante”) por sua vez, apresentaram valores mais elevados de condutividade elétrica, turbidez, maior abundância de larvas de Chironomus e menor riqueza de táxons, mostrando elevado impacto em função das atividades antrópicas. A avaliação rápida realizada com a composição da comunidade bentônica e as variáveis físicas e químicas da água foi suficiente na identificação das alterações na integridade ecológica causadas pela influência antrópica na bacia hidrográfica do rio Corumbá.
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Nakayama, Paula, Alberto Carvalho Peret, Johnatas Adelir-Alves, Olímpio Rafael Cardoso, Marcelo Renato Lamour, and Henry Louis Spach. "ENVIRONMENTAL DRIVERS OF FISH ASSEMBLAGES FROM THE SHALLOW INFRALITTORAL AREAS OF THE PARANAGUÁ BAY, SOUTHERN BRAZIL." Oecologia Australis 24, no. 04 (December 14, 2020): 917–27. http://dx.doi.org/10.4257/oeco.2020.2404.14.

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The composition of estuarine fish fauna is dynamic and complex. Despite the variation in fish fauna in estuaries, it is possible to observe some species associated with microhabitats. The assemblage composition of these communities is apparently derived from habitat selection. The aim of this study was to assess the structure of the demersal fish fauna of the Paranaguá Bay and its relationship with biotic and abiotic factors. To this end, monthly collections were conducted using an otter trawl, from October 1999 to September 2000, at five sites in the shallow infralittoral. Biotic (organic matter, and invertebrates) and abiotic factors (salinity, temperature, pH, dissolved oxygen, seston, and nutrients) were recorded during sampling. A total of 6,623 individuals were captured, belonging to 2 species of Chondrichthyes and 53 species of Actinopterygii (26 families). Sciaenidae was the most representative in terms of richness, with 11 species, and Ariidae was the most representative in terms of abundance. The catfish Cathorops spixii was the most abundant species, representing 21 % of the entire catch. There were significant differences in the composition and abundance of the fish fauna among the studied areas, as evidenced by the Shannon-Wiener diversity index. Such differences seem to be related to the complexity of habitats, which occur due to different types of bottom cover found at each sampling site. The abiotic variables indicated little influence on the structure of the fish assembly. These results contribute to a better understanding of the fish fauna from the shallow infralittoral areas of the Paranaguá Bay, and provide data to decision makers for better implementation of management and conservation measures.
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Henry Torriente, Pedro P., Juan M. García Delgado, Osvaldo A. Fosado Téllez, and Abelardo Domínguez Goizueta. "Obtención de modelos matemáticos para la elaboración de tablas de volumen de madera en bolo para cuatro especie de latifolias de la ciénaga de zapata." Ra Ximhai, December 31, 2009, 297–306. http://dx.doi.org/10.35197/rx.05.03.2009.04.ph.

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En Cuba continua prevaleciendo el empleo de tablas de cubicación inexactas y de procedencia extranjera en las mediciones de las especies maderables que crecen en el país. En el presente trabajo se expresan los resultados de la integración en una ecuación y por ende en una sola tabla de volumen, de cuatro ecuaciones de regresión obtenidas a partir del mismo número de especies independientes: Lysiloma latisiliquum Benth. (soplillo), Bursera simaruba Sargent. (almácigo), Calophyllum antillanun Britton. (ocuje) y Bucida palustris Borhidi. (júcaro de Ciénaga); con el objetivo de perfeccionar la cubicación de la madera en bolo en la Ciénaga de Zapata y dar mayor utilidad práctica a los resultados obtenidos. Se utiliza el método del análisis de las covarianzas propuesto por Sigarroa (1985). Las ecuaciones obtenidas del conjunto de especies presentaron estadísticos de ajuste que las hacen comparables con las especies individuales. Igualmente, sus sesgos se comportaron con corteza y sin ella inferior al 3 %, siendo inferiores también a los reportados por las tablas utilizadas en la producción que rebasaron el 10%. Finalmente, se hizo un análisis no parámetrico de Kruskal Wallis, para comparar, las ecuaciones del conjunto de especies, la de la especie y el valor real obtenido con los datos independientes de la misma, no encontrándose diferencias estadísticamente significativa entre cada una de ellas. La ecuación propuesta permite mediante el aumento de la exactitud en la cubicación cuantificar volúmenes de madera en bolo que con anterioridad por falta de exactitud de los métodos precedentes no entraban dentro de los cálculos de la madera en bolo que se asimilaba por la industria y que alcanzan la cifra de 1180 m3 , lo que representa una ganancia adicional para las unidades productoras de 57 029 pesos, mejorando también las condiciones económicas y laborales del obrero forestal
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17

A, Suriyadi, Mohamad Sofyan Harahap, and Ery Leksana. "Perbedaan Pengaruh Pemberian HES 6 % Dalam Larutan Berimbang Dengan HES 6 % Dalam Larutan Nacl 0,9 % Terhadap Perubahan pH, Strong Ion Difference Dan Klorida Pada Pasien Bedah Sesar Dengan Anestesi Spinal." JAI (Jurnal Anestesiologi Indonesia) 4, no. 1 (March 1, 2012). http://dx.doi.org/10.14710/jai.v4i1.6432.

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Latar belakang penelitian : Pemberian koloid sebagai preload pada bedah sesar dengan anestesi spinal lebih efektif dibandingkan kristaloid. Kebijakan pemilihan koloid berdasarkan jenis pelarutnya mulai dikembangkan terkait dengan dampak terhadap keseimbangan asam-basa.Tujuan : Melihat perbedaan pengaruh pemberian preload HES 6% dalam larutan NaCl 0,9% dengan HES 6% dalam larutan berimbang terhadap perubahan pH, SID dan kadar klorida pada pasien bedah sesar dengan anestesi spinal.Metode : Merupakan uji klinik eksperimental tahap II yang dilakukan secara acak tersamar ganda, menggunakan consecutive sampling, dibagi dua kelompok (n=24), kelompok HES 6% dalam larutan berimbang dan HES 6% dalam larutan NaCl 0,9%. Uji statistik t-test atau Wilcoxon signed rank test digunakan untuk membandingkan nilai pHSID, dan kadar klorida pada masing-masing kelompok, sedangkan uji statistik antarkelompok digunakan independent t-test atau Mann-Whitney U-test.Hasil : Nilai pH, SID, dan kadar klorida sebelum dan sesudah operasi antara NaCl 0,9% terdapat perbedaan yang tidak bermakna (p>0,05)Kesimpulan : Terdapat penurunan pH, penurunan SID dan peningkatan kadar klorida pada kelompok HES 6% dalam larutan NaCl 0,9% dibandingkan HES 6% kelompok HES 6 % dalam larutan berimbang dan HES 6% dalam larutan terdalam larutan berimbang secara tidak bermakna.
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18

KOLM, Hedda Elisabeth, Patricia Ribeiro Nunes de Melo dos SANTOS, and Klaus Dieter SAUTTER. "Bacteria in water and sediments of Guaratuba Bay, Paraná, Brazil." Tropical Oceanography 35, no. 1-2 (December 20, 2007). http://dx.doi.org/10.5914/tropocean.v35i1-2.5082.

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Estudou-se, na Baía de Guaratuba, a variabilidade temporal e espacial do bacterioplâncton em relação à variação da maré, e a variação espacial do bactériobentos. Foram analisadas a variabilidade de bactérias heterotróficas totais, biomassa bacteriana, bactérias heterotróficas cultiváveis halófilas e halófobas, coliformes totais e Escherichia coli. Os parâmetros bióticos foram correlacionados com a salinidade, temperatura, pH, seston, transparência da água, oxigênio dissolvido, granulometria e clorofila. Os resultados mostraram que na água, nos dois períodos de maré, os valores de salinidade, pH e oxigênio dissolvido foram mais elevados nas estações externas da baía. Os demais parâmetros foram mais elevados nas regiões abrigadas e nas estações internas. No sedimento observou-se uma correlação positiva entre as heterotróficas totais, a biomassa bacteriana, as halófobas, a matéria orgânica e o carbonato de cálcio nas estações internas. Nas estações localizadas na entrada da baía puderam ser observados valores elevados de silte, argila e bactérias halófilas. Na parte mais interna da baia foram registrados valores extremamente altos de areia e E. coli. Os resultados mostraram que na água, apesar da inversão da maré, e no sedimento, os valores mais elevados de bactérias foram encontrados nas estações internas ou abrigadas da baía. Palavras chave: bactérias; água; sedimento; Baía de Guaratuba; coliformes.
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19

Vrba, Jaroslav, Jiří Kopáček, Thomas Bittl, Jiří Nedoma, Alena Štrojsová, Linda Nedbalová, Leoš Kohout, and Jan Fott. "A key role of aluminium in phosphorus availability, food web structure, and plankton dynamics in strongly acidified lakes." Biologia 61, no. 20 (January 1, 2006). http://dx.doi.org/10.2478/s11756-007-0077-5.

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AbstractWe studied extracellular acid phosphatase activity (AcPA) of planktonic microorganisms, aluminium (Al) speciation, and phosphorus (P) cycling in three atmospherically acidified (pH of 4.5–5.1) mountain forest lakes: Čertovo jezero (CT), Prášilské jezero (PR), and Plešné jezero (PL) in the Bohemian Forest (Šumava, Böhmerwald). Microorganisms dominated pelagic food webs of the lakes and crustacean zooplankton were important only in PR, with the lowest Al concentrations (193 µg L−1) due to 3–4 times lower terrestrial input. The lakes differed substantially in Al speciation, i.e., in the proportion of ionic and particulate forms, with the highest proportion of ionic Al in the most acid CT (pH = 4.5). The P concentration in the inlet of PL (mean: 22.9 µg L−1) was about five times higher than in CT and PR (3.9 and 5.1 µg L−1, respectively). Average total biomass of planktonic microorganisms in PL (593 µg C L−1) was, however, only ∼2-times higher than in CT and PR (235 and 272 µg C L−1, respectively). Enormous AcPA (means: 2.17–6.82 µmol L−1 h−1) and high planktonic C : P ratios suggested severe P limitation of the plankton in all lakes. Comparing 1998 and 2003 seasons, we observed changes in water composition (pH and Al speciation) leading to a significant increase in phytoplankton biomass in the lakes. The increase in the seston C : P ratio during the same time, however, indicates a progressive P deficiency of the lakes. The terrestrial Al inputs, together with in-lake processes controlling the formation of particulate Al, reduced P availability for planktonic microorganisms and were responsible for the differences in AcPA. At pH < 5, moreover, ionic Al forms caused inhibition of extracellular phosphatases. We postulate that both particulate and ionic Al forms affect P availability (i.e., inhibition of extracellular phosphatases and inactivation of P), specifically shape the plankton composition in the lakes and affect plankton recovery from the acid stress.
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20

Rizky, Dhany. "ANALISIS GEOKIMIA DAERAH PANASBUMI CIPANAS, KECAMATAN CIPANAS, KABUPATEN LEBAK, PROVINSI BANTEN." Jurnal Eksakta Kebumian 1, no. 2 (November 22, 2021). http://dx.doi.org/10.25105/jek.v1i2.10634.

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Indonesia mempunyai potensi panasbumi yang cukup besar berdasarkan letak geografis dan kondisi geologi yang dilewati oleh zona sesar dan banyaknya gunungapi. Sehingga hal tersebut mendorong penulis untuk memahami karakteristik panasbumi yang bekerja. Tujuan penelitian ini adalah untuk mengetahui karakteristik geokimia panasbumi berdasarkan data manifestasi permukaan dan pembuatan model tentatif daerah penelitian. Lokasi daerah penelitian terletak pada Daerah Cipanas dan sekitarnya, Kecamatan Cipanas, Kabupaten Lebak, Provinsi Banten. Metode penelitian adalah pengambilan data litologi dan data geokimia daerah penelitian berupa unsur terlarut manifestasi, pencatatan suhu, pH, dan isotop. Secara regional daerah penelitian terdiri dari Formasi Diorit Kuarsa, Formasi Dasit, Formasi Bojongmanik anggota lempung, Formasi Bojongmanik anggota gamping, dan Batuan Gunungapi Endut. Secara lokal tersusun dari Satuan Dasit, Satuan Batulempung, Satuan Andesit, Satuan Batugamping, dan Satuan Breksi. Manifestasi panasbumi berjenis volcanogenic-high relief dengan jenis air bikarbonat, satu sumber reservoir, kondisi fluida immature water, geotermometer berkisar 120-147°C, isotop meteoric line. Dengan berdasarkan hasil analisis tersebut dapat diperoleh model tentatif yang relevan. Kata-kata kunci: Cipanas, Geokimia air, Isotop, Geotermometer
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21

Machado, Carla Gambagorte. "CARACTERIZAÇÃO QUÍMICA DOS AGREGADOS E SEDIMENTOS SUPERFICIAIS NA ZONA DE MÁXIMA TURBIDEZ NO COMPLEXO ESTUARINO DE PARANAGUÁ (CEP)." Boletim Paranaense de Geociências 65 (December 31, 2011). http://dx.doi.org/10.5380/geo.v65i0.7412.

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A investigação da estrutura físico-química da coluna d’ água no ponto fixo localizado na zona de máxima turbidez do Complexo Estuarino de Paranaguá avaliou a água através dos parâmetros convencionais. O pH sofreu baixa variação, a saturação de CO2 manteve índices elevados de 125 – 992%, a clorofila-a –0,62 até 6,83mg.dm-3, o seston de 2,82 a 117,09 mg.dm-3 e para o oxigênio dissolvido 5,61 a 8,10 mg.dm-3. Os nutrientes inorgânicos dissolvidos apresentaram as seguintes concentrações: fosfato de 0,33 a 3,28 mmol.dm-3, o silicato 7,14 a 70,41 mmol.dm-3, o nitrato 0,03 até 34,78 mmol.dm-3, o nitrito de 0 a 1,12 mmol.dm-3 e o nitrogênio amoniacal de 0,08 a 7,95 mmol.dm-3. O fósforo orgânico total ostentou valores de 0,33 a 4,73 mmol.dm-3 enquanto que o nitrogênio orgânico total variou de 8,28 a 28,66 mmol.dm-3. De modo geral perante estes resultados, a qualidade d’ água segundo BRICKER (2003) e CARMOUZE (1994) é boa, encontrando-se nos limites traçados por estes autores. As concentrações dos agregados mostrou-se maior nas campanhas de sizígia dos dois períodos estudados (chuvoso e seco) 19,2 a 299,5 mg.dm-3, sendo que a estação verão ostentou os maiores resultados devido às chuvas fortes que carregam material proveniente dos rios. Os elementos metálicos arsênio e cádmio não foram detectados nos agregados pois o limite de detecção não foi suficientemente sensível. Os sedimentos apresentaram concentrações normais para esses elementos sem apresentar risco para o sistema.O trabalho mostrou que o principal meio de transporte de contaminantes metálicos é o material particulado em suspensão.
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