Enhancement of Autotrophic Production by Nutrient Addition in a Coastal Rainforest Stream on Vancouver Island

1978 ◽  
Vol 35 (1) ◽  
pp. 28-34 ◽  
Author(s):  
John G. Stockner ◽  
K. R. S. Shortreed

In 1976 streamside nutrient-enrichment experiments were conducted using wooden troughs. Tripling of the PO4-P concentration, with or without a similar increase of NO3-N, increased algal biomass on the troughs by 8 times after 35 days. Increasing NO3-N alone had no appreciable effect on algal growth. A sloughing of algal biomass in August 1976 is believed to have been due to the instability of the heavy algal mat on the troughs and to the very poor light conditions that prevailed throughout August. Visual observation indicated that the relatively heavy algal population in Carnation Creek rapidly declined concurrent with the decline in the troughs. The percentage of diatoms in the algal assemblage remained the same in all troughs, and Fragilaria vaucheriae replaced Achnanthes minutissima as dominant on the phosphorus enriched trough. No shift to green or blue-green algal dominated assemblages occurred despite alteration of the N:P ratio. The dynamics of species succession, distribution, and growth, with and without nutrient addition, are discussed. Key words: stream fertilization, autotrophic production, algal succession, N:P ratio, algal distribution, rainforest, algal biomass, diatoms, blue-green algae

2020 ◽  
Vol 12 (14) ◽  
pp. 16979-16992
Author(s):  
Sharada Jagannath Ghadage ◽  
Vaneeta Chandrashekhar Karande

Blue green algae are the photosynthetic prokaryotes representing a wide distribution in habitat, i.e., temperate, tropical, and polar region.  Paddy fields are the best studied aquatic ecosystems on earth which fulfill all the necessary demands required for blue green algal growth.  Blue green algal role in enhancement of paddy yield has been studied worldwide.  Sustainable utilization of an organism for community use depends on how successfully the ecology of that organism is understood.  Twenty-eight chroococcalean blue green algal taxa were recorded from the study area.  They were taxonomically investigated and found to belong to two families and 11 genera.   The first family Chroococcaceae was the largest family with 10 genera and 26 species while the second family Entophysalidaceae had only one genus and two species.  The genus Gloeocapsa from the family Chroococcaceae exhibited largest species diversity (21.42%), as well as taxa Chlorogloea fritschii of family Entophysalidaceae showed species abundance from the study area.  All heterocystous blue green algal forms are capable of fixation of atmospheric N2.  Many of the non-heterocystous or unicellular blue green algae also have the capacity of N2 fixation.  The taxonomical documentation of chroococcalean blue green algae provide information about such indigenous unicellular blue green algae which will help in the development of niche specific inoculants as biofertilizers for rice fields of the study region.  


1997 ◽  
Vol 54 (9) ◽  
pp. 1965-1975 ◽  
Author(s):  
P A Soranno

Blue-green algal blooms, which can occur mixed throughout the epilimnion or as scums at the lake surface, develop in response to a variety of factors. However, it is still unclear what conditions suggest that blooms are imminent or how far in advance blooms can be forecast. I assessed the predictability of surface scums and epilimnetic blooms from limnological, physical, and meteorological variables using data sampled daily during summer and fall 1993 in Lake Mendota, Wisconsin. Daily chlorophyll a (a measure of blue-green algal biomass) was correlated to some weather, physical, and grazing variables at lags ranging from 0 to 9 days. Conditions immediately preceding surface scums were variable, making predictions difficult. However, during surface scums, Secchi disk depth, wind velocity, atmospheric pressure, and precipitation were significantly different than when the scums were absent. Based on predictors examined in this study, I developed criteria that identify the conditions sufficient for scums to form. In Lake Mendota, conditions sufficient for surface scum formation (proper weather and water column conditions and a pre-existing algal population) occur much more often than scums are observed. This study shows the importance of weather in determining both epilimnetic blue-green algal biomass and surface scum formation.


1989 ◽  
Vol 46 (7) ◽  
pp. 1232-1237 ◽  
Author(s):  
Daniel E. Canfield Jr. ◽  
Edward Phlips ◽  
Carlos M. Duarte

Phytoplankton samples collected from 165 Florida lakes were examined to determine relationships between blue-green algal abundance and environmental conditions. Blue-green algal biomass in the Florida samples was weakly correlated (r = −0.34) with water transparency and the concentration of total nitrogen (TN) (r = 0.47) and total phosphorus (TP) (r = 0.33). The relative contribution of blue-green algae to total phytoplankton biomass, however, did not decrease with TN/TP > 29. Blue-green algal biomass was strongly correlated (r = 0.90) to total algal biomass, and blue-green algae became consistently dominant when total algal biomass exceeded 100 mg/L.


1987 ◽  
Vol 44 (7) ◽  
pp. 1337-1342 ◽  
Author(s):  
Annette M. Trimbee ◽  
E. E. Prepas

The relative biomass of blue-green algae in freshwater (total dissolved solids < 500 mg∙L−1) Alberta lakes was consistently underestimated by two recent empirical models based on total nitrogen (TN), total phosphorus (TP), Secchi disc depth (SD), and depth of the mixed layer (Zm). We regrouped the data used in these empirical models to eliminate the potential biases introduced by including data from lakes not in dynamic equilibrium and generated a new model based on TP. This new model accounted for 11% more of the variation in relative blue-green algal biomass than the original model based on TN, TP, SD, and Zm and 21% more than the model based on TN to TP ratios and SD to Zm ratios. This new model was also a much better predictor of the relative biomass of blue-green algae in Alberta lakes than the original models. In addition, for lakes in Alberta, TP was a much better predictor of total blue-green algal biomass than TN or the TN to TP ratio. Our analyses suggest that for large numbers of lakes, TP may be as good or better an indicator of relative and total biomass of blue-green algae than TN or TN to TP ratios.


1976 ◽  
Vol 22 (8) ◽  
pp. 1181-1185 ◽  
Author(s):  
Willy Lange

Voluminous and often fluffy sheaths surrounding blue-green algal cells are observed (a) in productive natural waters, (b) in bacteria-containing laboratory cultures growing in inorganic nutrient media with added bacteria-assimilable organic matter, and (c) in axenic cultures in the same inorganic media even without added organic matter. The sheaths of bacteria-associated species in inorganic media without added organic matter are, by comparison, thin, and growth is meager. Repeated observations show that voluminous sheaths and vigorous growth of algal species are associated. It is suggested that formation and retention of a voluminous sheath provide a microenvironment around the algal cell where essential nutrients, present at only submarginal levels in the surrounding water, are concentrated and become readily available to the cell. This increase in nutrient concentration above a critical level, in turn, leads to vigorous algal growth. The voluminous sheath produced by the alga is not attacked by alga-associated bacteria when other assimilable organic matter is available: but in the absence of a more suitable food, the bacteria feed on the less desirable gelatinous sheath, markedly reducing its thickness and causing meager algal growth.


1983 ◽  
Vol 40 (9) ◽  
pp. 1419-1429 ◽  
Author(s):  
Wayne A. Wurtsbaugh ◽  
A. J. Horne

Clear Lake, California, is warm, shallow, polymictic, and eutrophic. During 1975, levels of dissolved (< 0.45 μm) iron in all three basins of Clear Lake were always low (15–30 μg∙L−1) and decreased to 2 μg∙L−1 during the major bloom of Aphanizomenon flos-aquae. Nitrogen fixation (acetylene reduction) rates of the blue-green algal populations were stimulated as much as 500% above control levels by iron additions in laboratory and in situ large-volume bioassays. Carbon fixation rates and chlorophyll a levels were also significantly stimulated by iron additions, but usually less rapidly and to a lesser extent than N2 fixation. Additions of nitrate stimulated carbon fixation and chlorophyll production but inhibited increases in nitrogen fixation. Phosphate additions either had no effect or produced a mixture of stimulation or depression of all three variables. The bioassays indicate that the growth of blue-green algae and other algae in Clear Lake is usually directly limited by combined nitrogen and occasionally by iron or phosphorus. Low iron levels aggravate the effects of low nitrogen by limiting nitrogen fixation, thus reducing blue-green algal growth.


2021 ◽  
Vol 11 (4) ◽  
pp. 1788
Author(s):  
Thanh-Tri Do ◽  
Binh-Nguyen Ong ◽  
Tuan-Loc Le ◽  
Thanh-Cong Nguyen ◽  
Bich-Huy Tran-Thi ◽  
...  

In the production of astaxanthin from Haematococcus pluvialis, the process of growing algal biomass in the vegetative green stage is an indispensable step in both suspended and immobilized cultivations. The green algal biomass is usually cultured in a suspension under a low light intensity. However, for astaxanthin accumulation, the microalgae need to be centrifuged and transferred to a new medium or culture system, a significant difficulty when upscaling astaxanthin production. In this research, a small-scale angled twin-layer porous substrate photobioreactor (TL-PSBR) was used to cultivate green stage biomass of H. pluvialis. Under low light intensities of 20–80 µmol photons m−2·s−1, algae in the biofilm consisted exclusively of non-motile vegetative cells (green palmella cells) after ten days of culturing. The optimal initial biomass density was 6.5 g·m−2, and the dry biomass productivity at a light intensity of 80 µmol photons m−2·s−1 was 6.5 g·m−2·d−1. The green stage biomass of H. pluvialis created in this small-scale angled TL-PSBR can be easily harvested and directly used as the source of material for the inoculation of a pilot-scale TL-PSBR for the production of astaxanthin.


REAKTOR ◽  
2014 ◽  
Vol 15 (1) ◽  
pp. 27
Author(s):  
M Mawardi ◽  
Edison Munaf ◽  
Soleh Kosela ◽  
Widayanti Wibowo

Karakteristik pemisahan ion Cr3+ dan Cr6+ dalam larutan melalui proses biosorpsi menggunakan biomassa alga hijau Spirogyra subsalsa dengan sistem batch telah diteliti. Dalam pelaksanaannya diawali dengan melakukan analisis kualitatif gugus fungsi dalam biomassa menggunakan instrumen FTIR, kemudian dipelajari karakteristik pengaruh variabel pH awal larutan, ukuran partikel biosorben, kecepatan pengadukan, pengaruh pemanasan biosorben, laju penyerapan, pengaruh konsentrasi larutan ion logam terhadap kapasitas serapan biomassa alga. Berdasarkan spektra spektroskopi FTIR dapat disimpulkan bahwa  biomassa alga hijau S. Subsalsa mengandung gugus-gugus karboksilat, amina, amida, amino, karbonil dan hidroksil, disamping adanya senyawa silikon, belerang dan fosfor. Hasil penelitian yang diperoleh  memperlihatkan bahwa kapasitas biosorpsi sangat dipengaruhi oleh pH larutan, waktu kontak dan konsentrasi awal larutan. Biosorpsi optimum kation Cr3+ terjadi pada pH 4,0 sedangkan ion Cr6+ terjadi pada pH 2,0 kemudian berkurang dejalan dengan naiknya pH larutan. Perhitungan dengan persamaan Isoterm Langmuir diperoleh data kapasitas serapan maksimum biomassa alga S. subsalsa untuk masing-masing ion Cr3+ dan Cr6+ adalah 1,82 mg (0,035 mmol) dan 1,51 mg (0,029 mmol) per gram biomassa kering. Kinetika biosorpsi berlangsung relatif cepat, dimana selama selang waktu 30 menit, masing-masing ion terserap sekitar 95,7%; dan 86,5%. Daya serap biomassa juga dipengaruhi kecepatan pengadukan, sedangkan faktor ukuran partikel dan pemanasan biosorben kurang mempengaruhi daya serap biomassa. Key Word : biosorpsi, spirogyra subsalsa, krom(III), krom(VI), sistem batchAbstract Separation of Ion Chromium(III) and Chromium(IV) In Solution Using Green Algae Biomass Spirogyra subsalsa as Biosorbent. The characteristics of Cr3+andCr6+ ion separation in solution through biosorption process using green algal biomass Spirogyrasubsalsa with batch systems have been investigated. The study began with aqualitative analysis of functional groups in biomass using FTIR instrument, then followed by a study of the characteristics of influences by several variables, such as: the initial pH of the solution,the size of biosorben particles, stirring speed, the effect of heating the biosorben, the rate of absorption, and the effect of metal ion concentration in solution on the absorption capacity of algal biomass. Based on FTIR spectroscopy spectra gave a conclusion that biomass of green algae S.subsalsa contains carboxylate groups, amine, amide, amino, carbonyl and hydroxyl, in addition to silicon, sulfur, and phosphorus compounds. The results showed that the biosorption capacity was strongly influenced by pH, contact time, and initial concentration ofthe solution. The optimum biosorption of Cr3+cation occurred at pH 4.0 while that of Cr6+ions occurred at pH 2.0 and then decreased with the increasing pH of solution. The calculation of Langmuir isotherm equation showed that the maximum absorption capacity of algal biomass S.subsalsa for Cr3+and Cr6+ ion respectively was 1.82mg (0.035 mmol) and 1.51 mg (0.029 mmol) pergram of dry biomass. The kinetics of biosorption took place relatively quick, in which during the 30minutes time interval, each ion was absorbed approximately 95.7%; and 86.5%. The absorptive capacity of biomass was also influenced by stirring speed, while the size of particles and heating biosorben gave lessinfluence to the absorption of biomass.


Sign in / Sign up

Export Citation Format

Share Document