Effects of acidity on the phytoplankton and primary productivity of selected northern Ontario lakes

1976 ◽  
Vol 54 (22) ◽  
pp. 2546-2561 ◽  
Author(s):  
R. E. Kwiatkowski ◽  
J. C. Roff
Keyword(s):  
Species Composition ◽  
Primary Production ◽  
Diversity Index ◽  
Euphotic Zone ◽  
Northern Ontario ◽  
Phytoplankton Diversity ◽  
Ph Values ◽  
Significant Relationships ◽  
Percentage Similarity ◽  
Community Coefficient

The effects of acidity on primary production, species composition, and abundance of phytoplankton were investigated in six lakes in the Sudbury area of Ontario, where pH values lay between 4.05 and 7.15. Significant relationships showing an increase in water transparency and decrease in chlorophyll a concentration with declining pH were found. Percentage similarity of community (PSc) and community coefficient (CC) values were highest between lakes closest in pH, reflecting progressive changes in species composition. As the pH declined, Chlorophyta diminished in importance and the Cyanophyta became dominant. The phytoplankton diversity index (DI) remained relatively unchanged between pH values of 7.0 to 5.0 but decreased at lower values. Primary production in milligrams C metre−3 hour−1 was reduced in lakes below pH 5.5; however, as a result of the increase in depth of euphotic zone accompanying more acidic conditions, primary production in milligrams C metre−2 hour−1 remained high down to pH 4.4, below which it was drastically reduced.

Zooplankton and zoobenthos communities of selected northern Ontario lakes of different acidities

1977 ◽  
Vol 55 (6) ◽  
pp. 899-911 ◽  
Author(s):  
J. C. Roff ◽  
R. E. Kwiatkowski
Keyword(s):  
Chlorophyll A ◽  
Body Length ◽  
Primary Productivity ◽  
Significant Relationship ◽  
Standing Crop ◽  
Diversity Index ◽  
Northern Ontario ◽  
Ph Values ◽  
Egg Ratio ◽  
Percentage Similarity

The zooplankton and zoobenthos were investigated in six lakes in the Sudbury area of Ontario in which pH values lay between 4.05 and 7.15. Zooplankton showed a significant reduction in species and numbers at the lower pH levels; the Rotifera showed the greatest changes. Zooplankton diversity index (DI) declined sharply below pH 5.3. Percentage similarity of community (PSc) and coefficient of community (CC) values were highest between lakes closest in pH, reflecting progressive changes in species composition.Significant relationships were found between the zooplankton standing crop and chlorophyll a concentrations and the zooplankton standing crop and areal primary productivity. Dry weights for Holopedium gibberum and Diaptomus minutus were lowest in the most acidic lakes. No significant relationship between body length or egg ratio, and lake pH were found for D. minutus.The zoobenthos was represented by a variety of taxa; however, only genera belonging to the Oligochaeta and Tendipedidae were represented in all study lakes. Zoobenthos DI showed only a slight decrease below a pH of 4.9. PSc and CC values for the zoobenthos displayed similar though not as distinct patterns as those found in the plankton.

scholarly journals Primary production in the Chukchi Sea with potential effects of freshwater content

2016 ◽  
Vol 13 (3) ◽  
pp. 737-749 ◽  
Author(s):  
M. S. Yun ◽  
T. E. Whitledge ◽  
D. Stockwell ◽  
S. H. Son ◽  
J. H. Lee ◽  
...  
Keyword(s):  
Primary Production ◽  
Chukchi Sea ◽  
Euphotic Zone ◽  
Northern Region ◽  
Current Status ◽  
Production Rates ◽  
Significant Relationships ◽  
Using Data ◽  
Seasonal And Interannual Variations

Abstract. The in situ primary production rates and various environmental variables were investigated in the Chukchi Sea during the RUSALCA expedition, which was conducted in 2012, to identify the current status of primary production. A 13C–15N dual-tracer technique was used to measure the daily primary production rates, which ranged from 0.02 to 1.61 g C m−2 d−1 (mean ±SD  =  0.42 ± 0.52 g C m−2 d−1). The primary production rates showed large regional differences, with the southern region (0.66 ± 0.62 g C m−2 d−1) producing approximately 5 times as much as the northern region (0.14 ± 0.10 g C m−2 d−1), which was primarily due to the differences in phytoplankton biomasses induced by regional nutrient conditions. The primary production rates in the Chukchi Sea were averaged using data acquired during the three different RUSALCA expeditions (2004, 2009, and 2012) as 0.33 g C m−2 d−1 (SD  =  0.40 g C m−2 d−1), which was significantly lower than previously reported rates. In addition to strong seasonal and interannual variations in primary production, recent decreases in the concentrations of major inorganic nutrients and chlorophyll a could be among the reasons for the recent low primary production in the Chukchi Sea because the primary production is mainly affected by nutrient concentration and phytoplankton biomass. The nutrient inventory and primary production appear to be largely influenced by the freshwater content (FWC) variability in the region due to the significant relationships between FWC, nitrate inventory (r  =  0.54, p < 0.05), and primary production rates (r  =  0.56, p < 0.05). Moreover, we found highly significant relationships between the nutrient inventory and the primary production rates (r  =  0.75, p < 0.001). In conclusion, the primary production in the Chukchi Sea is primarily controlled by nutrient availability, which is strongly related to the FWC variability. Our results imply that the predicted increase in freshwater accumulation might cause a decrease in primary production by lowering the nutrient inventory in the euphotic zone of the Chukchi Sea.

scholarly journals The potential effects of fresh water content on the primary production in the Chukchi Sea

2015 ◽  
Vol 12 (16) ◽  
pp. 13511-13544
Author(s):  
M. S. Yun ◽  
T. E. Whitledge ◽  
D. Stockwell ◽  
J. H. Lee ◽  
J. W. Park ◽  
...  
Keyword(s):  
Primary Production ◽  
Chukchi Sea ◽  
Euphotic Zone ◽  
Northern Region ◽  
Current Status ◽  
Production Rates ◽  
Significant Relationships ◽  
Using Data ◽  
Seasonal And Interannual Variations

Abstract. The in situ primary production rates and various environmental variables were investigated in the Chukchi Sea during the 3rd RUSALCA expedition, which was conducted in 2012, to identify the current status of primary production. A 13C-15N dual tracer technique was used to measure the daily primary production rates, which ranged from 0.02 to 1.61 g C m−2 d−1 (mean ± SD = 0.42 ± 0.52 g C m−2 d−1). The primary production rates showed large regional differences, with the southern region (0.66 ± 0.62 g C m−2 d−1) producing approximately five times as much as the northern region (0.14 ± 0.10 g C m−2 d−1), which was primarily due to the differences in phytoplankton biomasses induced by regional nutrient conditions. The primary production rates in the Chukchi Sea were averaged using data acquired during the three different RUSALCA expeditions (2004, 2009, and 2012) as 0.33 g C m−2 d−1 (SD = 0.40 g C m−2 d−1), which was significantly lower than previously reported rates. In addition to strong seasonal and interannual variations in primary production, recent decreases in the concentrations of major inorganic nutrients and chlorophyll a could be among the reasons for the recent low primary production in the Chukchi Sea because the primary production is mainly affected by nutrient concentration and phytoplankton biomass. The nutrient inventory and primary production appear to be largely influenced by the freshwater content (FWC) variability in the region due to the significant relationships between FWC, nitrate concentrations (r = 0.54, p < 0.05) and primary production rates (r = 0.56, p < 0.05). Moreover, we found highly significant relationships between the nutrient levels and the primary production rates (r = 0.75, p < 0.001). In conclusion, the primary production in the Chukchi Sea is primarily controlled by nutrient availability which is strongly related to the FWC variability. Our results imply that the predicted increase in freshwater accumulation might cause a decrease in primary production by lowering the nutrient inventory in the euphotic zone of the Chukchi Sea.

STRUKTUR KOMUNITAS MAKRO ALGA DI PESISIR PULAU KECAMATAN BULANG

SIMBIOSA ◽  
2014 ◽  
Vol 3 (2) ◽  
Author(s):  
Notowinarto Notowinarto ◽  
Ramses Ramses ◽  
Mulhairi Mulhairi
Keyword(s):  
Community Structure ◽  
Diversity Index ◽  
Algal Species ◽  
Algal Communities ◽  
Marine Life ◽  
Ph Values ◽  
Abundance Patterns ◽  
Coastal Marine ◽  
Temperature Parameter ◽  
Important Value Index

Bulang districts Batam Islands of  Riau province (Riau Islands), its consists of many islands with as well as having the potential diversity of coastal marine life in particular kinds of macro algae or seaweed. Conducted research aimed to determine the structure of macro- algal communities in the intertidal zone islands. The results of the identification of algal species found 16 species are: the Order of Chlorophyceae as 6 spesies; Order Phaeophyceae as 2 spesies; and Order Rhodophyceae as 8 spesies. The community structure at the five stations showed the highest values were found in the island of dominance Cicir (D ' = 0.79) , uniformity index values on Tengah Island (E ' = 0.99) , while the island Balak had the highest diversity index (H ' = 0.88) , with the abundance patterns of population structure on the island is pretty good Central . Results of correlation analysis of regression between IVI types of algae with the conditions of environmental quality suggests that there is a significance (Fhit ˃ F table and the value of r = > 90 %) between IVI algae Halimeda sp and Cryptarachne polyglandulosa at each station with a temperature parameter surface (⁰C) , depth temperature (⁰C) and pH values. Keywords : Algae, Community Structure, Important Value Index.

Carabidae of Barnaul city parks: ecological characteristics and species composition

2018 ◽  
Vol 8 (2) ◽  
pp. 348-353
Author(s):  
E. A. Kuchina ◽  
N. D. Ovcharenko ◽  
L. D. Vasileva
Keyword(s):  
Species Composition ◽  
Diversity Index ◽  
Similarity Index ◽  
Life Forms ◽  
Ground Beetles ◽  
Forest Steppe ◽  
Ecological Groups ◽  
Dominant Group ◽  
Species Diversity Index ◽  
Steppe Species

<p>Anthropogenic impact on the population of ground beetles leads to a change in their numbers, structure of dominance, density, species composition, spectrum of life forms. This makes the beetles Carabidae a convenient and informative bioindicator of the ecological state of biocenoses. The material for this work was the Carabidae collections conducted in June-August 2016-2017 in the park zone of different regions of Barnaul, differing in location, area, hydrological regime, vegetation cover, purpose and anthropogenic load. When processing the material, the quantitative, species and generic composition of the carabidae was determined, calculations were made for such indicators as the Berger-Parker dominance index, the Shannon species diversity index (Hs), and the Jacquard species similarity index. The fauna (Coleoptera, Carabidae) of the park zone of Barnaul is represented by 55 species belonging to 20 genera. The dominant group is represented by species belonging to steppe, forest and polyzonal groups. Forest-steppe species of ground beetles as dominants have not been identified in any of the investigated territories. The greatest variety of ecological groups was noted on the territory of the Yubileyny рark, which is explained by the presence of zones with various microclimatic conditions, the presence of a birch grove that flows through the park with the Pivovarka River, and a wide log in the park. Registered species belong to eight groups of life forms belonging to two classes - zoophagous and myxophytophagous. On the numerical and species abundance, zoophages predominate. The spectrum of life forms corresponds to the zonal spectrum characteristic of the forest-steppe zone.</p><p> </p>

scholarly journals A stochastic, Lagrangian model of sinking biogenic aggregates in the ocean (SLAMS 1.0): model formulation, validation and sensitivity

2016 ◽  
Vol 9 (4) ◽  
pp. 1455-1476 ◽  
Author(s):  
Tinna Jokulsdottir ◽  
David Archer
Keyword(s):  
Primary Production ◽  
Degradation Kinetics ◽  
Mechanistic Model ◽  
Euphotic Zone ◽  
Lagrangian Model ◽  
Zooplankton Grazing ◽  
Aggregate Model ◽  
Size Spectra ◽  
Sea Floor ◽  
Individual Particles

Abstract. We present a new mechanistic model, stochastic, Lagrangian aggregate model of sinking particles (SLAMS) for the biological pump in the ocean, which tracks the evolution of individual particles as they aggregate, disaggregate, sink, and are altered by chemical and biological processes. SLAMS considers the impacts of ballasting by mineral phases, binding of aggregates by transparent exopolymer particles (TEP), zooplankton grazing and the fractal geometry (porosity) of the aggregates. Parameterizations for age-dependent organic carbon (orgC) degradation kinetics, and disaggregation driven by zooplankton grazing and TEP degradation, are motivated by observed particle fluxes and size spectra throughout the water column. The model is able to explain observed variations in orgC export efficiency and rain ratio from the euphotic zone and to the sea floor as driven by sea surface temperature and the primary production rate and seasonality of primary production. The model provides a new mechanistic framework with which to predict future changes on the flux attenuation of orgC in response to climate change forcing.

scholarly journals Effects of grazing on plant species diversity and above ground biomass in a Trans- Himalayan Rangeland

1970 ◽  
Vol 17 (1) ◽  
pp. 25-31 ◽  
Author(s):  
Anita Pokharel ◽  
Madhu Chhetri ◽  
Chiranjibi P Upadhyaya
Keyword(s):  
Species Diversity ◽  
Species Composition ◽  
Plant Species ◽  
Diversity Index ◽  
Livestock Grazing ◽  
Above Ground Biomass ◽  
Ground Biomass ◽  
Grazing Effect ◽  
Significant Difference ◽  
Palatable Species

Limited information is available on the species composition, above ground biomass and its relations to grazing in a trans-Himalayan rangeland. Its assessment is essential for long term conservation and management. In the present study, we compared species composition, phenology, diversity index and biomass between controlled (without grazing) and open (free grazing) plots to assess the effects of grazing in the selected experimental sites of Upper Mustang during July and November 2005. Species encountered were classified as high, medium, low and non palatable and in three life form categories-grasses, shrubs and forbs. The experimental sites are dominated by forbs (80%) followed by grasses (15%) and shrubs (5%). Disturbance caused by grazing affects the phenological characteristics of the plant community. Result also reveals that species diversity, maximum possible diversity, evenness and species richness was higher in the grazed plots during July and November. A comparison of the aboveground biomass in July showed that mean percentage biomass of high, medium and low palatable species is higher in ungrazed plots. In November, the percentage biomass of only medium palatable species was higher in ungrazed plots and rest of the category is higher in grazed plots. Significant difference in July, a peak growing seasons for most of the plant species in the region reveals that the pasture has impact of livestock grazing. Keywords: Biomass, diversity, grazing effect, rangeland, species Banko Janakari: A journal of forestry information for Nepal Vol.17(1) 2007 pp.25-31

scholarly journals The possibility of reclamation criteria success in Indonesia: soil condition, vegetation structure and species composition

2021 ◽  
Vol 9 (1) ◽  
pp. 3201-3210
Author(s):  
Tedi Yunanto ◽  
Farisatul Amanah ◽  
Nabila Putri Wisnu
Keyword(s):  
Species Composition ◽  
Vegetation Structure ◽  
Diversity Index ◽  
Basal Area ◽  
Mineral Resources ◽  
Soil Condition ◽  
Mine Reclamation ◽  
Soil Conditions ◽  
Standard Interval ◽  
Chemical Conditions

There are two regulations for mine reclamation success in the forestry area in Indonesia, namely Minister of Forestry Regulation No. P.60/Menhut-II/2009 and Minister of Energy and Mineral Resources Decree No. 1827.K/30/MEM/2018. Both regulations rule vegetation and soil success. This study aims to analyse criteria parameters from both regulations in the mine reclamation and compare them to the surrounding secondary natural forest (SNF). This study was conducted in 6 six types of mine reclamation stand structures: 1, 4, 6, 9, 11-year-old plantation and SNF using 1 hectare of the circular plot each (total 6 ha). Soil samples were collected from 40 cm depth to analyse physical, biological and chemical conditions. Mine reclamation areas had almost similar physical, biological and chemical soil conditions with SNF. Nevertheless, due to the potential acid-forming (PAF) material from overburden, the 1-year-old plantation had pH = 3.23-3.27. The highest diversity index and the number of species and families in all reclamation areas were H’ = 1.82 (11-year-old); 14 species (9-year-old); and 11 families (9-year-old), comparing with SNF were H’ = 3.48; 67 species, and 31 families. Conversely, vegetation structure parameters in mine reclamation areas were higher than SNF (diameter at height breast (DBH; 1.3 m) = 28.42 cm; tree density = 469/ha; basal area = 35.04 m2/ha; and total height = 16.85 m). Compared to the SNF, vegetation structure and soil conditions are mostly possible for mine reclamation success. Still, species composition needs to be considered further as a standard interval to meet the criteria.

scholarly journals ANALISIS KOMUNITAS MANGROVE DI KECAMATAN SEKOTONG LOMBOK BARAT NTB

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Lalu Japa ◽  
Didik Santoso
Keyword(s):  
Cluster Analysis ◽  
Species Composition ◽  
Key Words ◽  
Tree Density ◽  
Mangrove Tree ◽  
Rhizophora Apiculata ◽  
Percentage Similarity ◽  
Percentage Covering ◽  
Very High ◽  
Program Version

Abstrak:Komunitas mangrove di kawasan Sekotong Lombok Barat telah diteliti untuk mengetahui komposisi spesies, kerapatan  individu setiap spesies,dan  persentase tutupannya. Total sebanyak 28 plot (kudrat) berukuran 10m x 10m dibuat pada 9 transek di lima stasiun. Foto tutupan kanopi mangrove dan parameter komposisi komunitas dianalisis menggunakan software ImageJ dan template spreadsheet. Data kerapatan pohon dan persentase tutupan mangrove dianalisis dengan ANOVA. Persentase kesamaan antara stasiun menggunakan Biodiversity Program Version 2 berdasarkan the Bray Curtis Cluster Analysis. Komunitas mangrove di Kecamatan Sekotong Lombok Barat teridenfikasi 8 spesies, meliputi 5 genus, dan 4 famili. Rhizophora apiculata tersebar disemua transek penelitian. Transek SKTM02B memiliki kerapatan pohon tertinggi sebesar 2800 pohon/ha. Tiga transek dengan persentase tutupan tertinggi berturut-turut SKTM04T, SKTM04, dan SKTM01A. Persentase kesamaan antar stasiun sangat tinggi mencapai 82,503 –  95,423%. Persentase kesamaan tertinggi (95,423%) terjadi antara stasium SKTM04 dan SKTM05. Kata kunci : mangrove, Sekotong, komposisi spesies, kerapatan, dan persentase tutupan Abstract: Community of mangrove in the area of Sekotong West Lombok has been researched to know the species composition,  individual density of each species, and percentage covering. Total number of 28 plots of 10 m x 10 m in size were set in 9 transects in 5 station. Photographs mangrove canopy covering and parameter of mangrove community composition were analyzed by using the software ImageJ and  template spreadsheet. ANOVA was applied for analyzing the data of mangrove  tree density and percentage covering. The Bray Curtis Cluster Analysis. using Biodiversity Program Version 2 was also used for analyzing the percentage similarity among station. The community of mangrove of Sekotong West Lombok consists of 8 species, 5 genera, dan 4 family. Rhizophora apiculata was recorded in all transects. The highest density (2800 trees/ha) of mangrove was recorde in ransect SKTM02B.. The three transects with the highest percentage covering were SKTM04T, SKTM04, dan SKTM01A, respectively. Percentages similarity among station were very high (82,503%  –  95,423%). SKTM04 and SKTM05 were the two station with  the highest percentage similarity (95,423%). Key words : mangrove, Sekotong, species composition, density, and percentage covering 

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