Nutrients versus physical factors in determining the primary productivity of waters with high inorganic turbidity

Hydrobiologia ◽  
1992 ◽  
Vol 238 (1) ◽  
pp. 177-182 ◽  
Author(s):  
Johan U. Grobbelaar
Keyword(s):  
Primary Productivity ◽  
Physical Factors ◽  
Inorganic Turbidity

Variability of ecosystem carbon source from microbial respiration is controlled by rainfall dynamics

2021 ◽  
Vol 118 (52) ◽  
pp. e2115283118
Author(s):  
Heng Huang ◽  
Salvatore Calabrese ◽  
Ignacio Rodriguez-Iturbe
Keyword(s):  
Primary Productivity ◽  
Microbial Growth ◽  
Net Primary Productivity ◽  
Carbon Sources ◽  
Terrestrial Ecosystems ◽  
Rainfall Regime ◽  
Physical Factors ◽  
Scale Parameters ◽  
Complex Interactions ◽  
Soil Heterotrophic Respiration

Soil heterotrophic respiration (Rh) represents an important component of the terrestrial carbon cycle that affects whether ecosystems function as carbon sources or sinks. Due to the complex interactions between biological and physical factors controlling microbial growth, Rh is uncertain and difficult to predict, limiting our ability to anticipate future climate trajectories. Here we analyze the global FLUXNET 2015 database aided by a probabilistic model of microbial growth to examine the ecosystem-scale dynamics of Rh and identify primary predictors of its variability. We find that the temporal variability in Rh is consistently distributed according to a Gamma distribution, with shape and scale parameters controlled only by rainfall characteristics and vegetation productivity. This distribution originates from the propagation of fast hydrologic fluctuations on the slower biological dynamics of microbial growth and is independent of biome, soil type, and microbial physiology. This finding allows us to readily provide accurate estimates of the mean Rh and its variance, as confirmed by a comparison with an independent global dataset. Our results suggest that future changes in rainfall regime and net primary productivity will significantly alter the dynamics of Rh and the global carbon budget. In regions that are becoming wetter, Rh may increase faster than net primary productivity, thereby reducing the carbon storage capacity of terrestrial ecosystems.

Effect of Stream Acidification on Periphyton Composition, Chlorophyll, and Productivity

1986 ◽  
Vol 43 (10) ◽  
pp. 1846-1858 ◽  
Author(s):  
Patrick J. Mulholland ◽  
J. W. Elwood ◽  
A. V. Palumbo ◽  
R. J. Stevenson
Keyword(s):  
Chlorophyll A ◽  
Green Algae ◽  
Primary Productivity ◽  
Inorganic Carbon ◽  
Cell Number ◽  
Specific Productivity ◽  
Physical Factors ◽  
Periphyton Community ◽  
Acidic Sites ◽  
Cell Biovolume

We determined periphyton community composition, cell number and biovolume, chlorophyll a density, and areal and chlorophyll-specific primary productivity along a pH (4.5–6.4) and total monomeric aluminum (0.018–0.242 mg∙L−1) gradient in high-elevation streams in the Great Smoky Mountains National Park (eastern Tennessee). The periphyton community was generally dominated by small chrysophytes and blue-green algae at sites with baseflow pH ≥ 5.5 and by diatoms and, to a lesser extent, green algae at sites with pH ≤ 5. Total cell biovolume, chlorophyll a density, and areal primary productivity were greatest at the most acidic sites. Chlorophyll-specific rates of primary production were not significantly different among sites, although the most acidic site was lowest. Experiments involving short-term manipulation of pH, inorganic carbon, PO4, and aluminum concentrations resulted in some statistically significant changes in chlorophyll-specific productivity, indicating that inorganic carbon concentrations at sites with pH < 6 and increased aluminum concentrations at sites with pH ≤ 5 may limit productivity at times. Studies of phosphatase activity and PO4 turnover indicated that the least acidic sites were the most phosphorus limited, perhaps the result of coprecipitation of aluminum and PO4 as pH increased downstream from acidified reaches. However, the low cell biovolume, Chlorophyll a density, and areal primary productivity at the second-order sites with pH ≥ 5.7, compared with the highly acidic second- and third-order sites (pH ≤ 5), appear to be the result of increased density of scraper/grazer macro-invertebrates at the higher pH sites. Low chlorophyll a density and areal primary productivity at the much larger fourth-order site (pH 6.4) may be the result of physical factors, such as increased scouring of the streambed, rather than chemical or biological factors.

scholarly journals DISTRIBUSI DAN SIKLUS NUTRIENT DI PERAIRAN ESTUARI SERTA PENGENDALIANNYA

OSEANA ◽  
2020 ◽  
Vol 45 (1) ◽  
pp. 28-39
Author(s):  
Deny Yogaswara
Keyword(s):  
Primary Productivity ◽  
Nutrient Loading ◽  
Negative Impact ◽  
Anthropogenic Activities ◽  
Waste Water Treatment ◽  
Treatment Plant ◽  
Waste Water Treatment Plant ◽  
Physical Factors ◽  
Marine Biota ◽  
Algae Bloom

Nutrient components (consist of nitrogen and phosphorus) are needed for healthy ecosystems and they are naturally widespread throughout the aquatic and terrestrial environment. Nutrient loading as a result of anthropogenic activities comes from rivers that flow into the estuary. The abundance and the cycles of nutrients in the estuary are affected by physical factors (i.e. hydrodynamic conditions such as currents and tides, turbidity and waves), biological factors (i.e. filter feeder organism) and chemical factors (i.e. material fixation and decomposition). To supporting estuarine food webs, phytoplankton and primary productivity are fundamental importance. Besides, they are also key drivers of biogeochemical cycling and play a central role in determining water quality. But on the contrary, within the same conditions, it has negative impact on the estuary environment. The negative impact of high primary productivity in the estuary can cause an algae bloom. Algae bloom occurs when abundant nutrients and optimum sunlight intensity, with the lowest current at the same time. Algae bloom has a negative impact on estuary ecosystems because it makes depleting of dissolved oxygen, with the mass death of marine biota such as fish as a consequence. Therefore, the amount of nutrients from anthropogenic activities have to be controlled and monitored before they flow to the river. The method to control the waste is treated in a Waste Water Treatment Plant (WWTP) system. This treatment by using the WWTP system could reduce the concentration of nutrients spread in the estuary and it will prevent the occurrence of algae bloom phenomena.

Limnological characteristics, community metabolism and management strategies of a coastal sinkhole in Cuba (Cenote Jennifer)

2020 ◽  
Vol 56 ◽  
pp. 24
Author(s):  
Roberto González-De Zayas ◽  
Liosban Lantigua Ponce de León ◽  
Liezel Guerra Rodríguez ◽  
Felipe Matos Pupo ◽  
Leslie Hernández-Fernández
Keyword(s):  
Hydrogen Sulfide ◽  
Primary Productivity ◽  
Major Ions ◽  
Saline Water ◽  
Management Strategies ◽  
Tourist Destination ◽  
Community Metabolism ◽  
Morphological Studies ◽  
Made In ◽  
Limnological Parameters

The Cenote Jennifer is an important and unique aquatic sinkhole in Cayo Coco (Jardines del Rey Tourist Destination) that has brackish to saline water. Two samplings were made in 1998 and 2009, and 4 metabolism community experiments in 2009. Some limnological parameters were measured in both samplings (temperature, salinity, pH, dissolved oxygen major ions, hydrogen sulfide, nutrients and others). Community metabolism was measured through incubated oxygen concentration in clear and dark oxygen bottles. Results showed that the sinkhole limnology depends on rainfall and light incidence year, with some stratification episodes, due to halocline or oxycline presence, rather than thermocline. The sinkhole water was oligotrophic (total nitrogen of 41.5 ± 22.2 μmol l−1 and total phosphorus of 0.3 ± 0.2 μmol l−1) and with low productivity (gross primary productivity of 63.0 mg C m−2 d−1). Anoxia and hypoxia were present at the bottom with higher levels of hydrogen sulfide, lower pH and restricted influence of the adjacent sea (2 km away). To protect the Cenote Jennifer, tourist exploitation should be avoided and more resources to ecological and morphological studies should be allocated, and eventually use this aquatic system only for specialized diving. For conservation purposes, illegal garbage disposal in the surrounding forest should end.

Satellite-based estimation of net primary productivity for southern China’s grasslands from 1982 to 2012

2017 ◽  
Vol 71 (3) ◽  
pp. 187-201 ◽  
Author(s):  
W Yang ◽  
T Lu ◽  
S Liu ◽  
J Jian ◽  
F Shi ◽  
...  
Keyword(s):  
Primary Productivity ◽  
Net Primary Productivity

PENGARUH RADIO DAN TELEVISI TERHADAP PARTISIPASI MASYARAKAT DALAM PENJAGAAN LINGKUNGAN DAN ALAM SEKITAR BAGI TERWUJUDNYA PEMBANGUNAN BERKELANJUTAN

2019 ◽  
Vol 13 (2) ◽  
pp. 115-123
Author(s):  
Ratu Mutialela Caropeboka
Keyword(s):  
Cultural Change ◽  
Social Factors ◽  
Information Dissemination ◽  
Local Community ◽  
Social Economic ◽  
Physical Factors ◽  
Development Communication ◽  
Balanced Development ◽  
Television Broadcasting ◽  
Major Process

The environment is also called the natural environment is a phenomenon that forms around life rather than humans, either biotic or abiotic. The surrounding phenomenon that affects people is not limited to physical factors solely, on the contrary social factors play an important role to explain how human activity can affect the environment and the natural surroundings. The essence and falsafa of development is a change, growth and equity in all fields and dimensions to a better state. Development communication is part of a major process that requires social, economic, political and cultural change in line with the requirements of the local community. The simultaneous formulation of information dissemination carried out by radio, is no longer the only option of society, because the community has designed and determined what information they need. Television broadcasting has an influence on patterns of public action to model, imitate information gained through impressions. Community participation in safeguarding the environment to achieve harmonious and balanced development is the driving and driving force for social change to achieve sustainable development. Lingkungan disebut juga alam sekitar adalah fenomena yang wujud di sekeliling kehidupan daripada manusia,baik biotik ataupun abiotik. Fenomena sekeliling yang mempengaruhi manusia tidak terbatas kepada faktor fisikal semata-mata, sebaliknya faktor sosial turut berperanan penting bagi menerangkan bagaimana aktivitas manusia dapat mempengaruhi lingkungan dan alam sekitar. Hakikat dan Falasafah pembangunan ialah suatu perubahan, pertumbuhan dan pemerataan dalam segala bidang dan dimensinya menuju keadaan yang lebih baik. Komunikasi pembangunan merupakan bahagian dari proses besar yang menghendaki adanya perubahan sosial, ekonomi, politik dan budaya yang sejalan dengan persyaratan keperluan masyarakat lokal. Formula keserentakan penyebaran informasi yang dilakukan melalui radio, tidak lagi menjadi satu-satunya pilihan masyarakat, karena masyarakatlah telah merancang dan menentukan informasi apa yang mereka perlukan. Siaran televisi mempunyai pengaruh pada pola tindakan masyarakat untuk mencontoh, meniru informasi yang didapat melalui tayangan. Partisipasi masyarakat menjaga lingkungan untuk mewujudkan pembangunan yang serasi dan seimbang adalah penggerak dan pengarah bagi perubahan sosial untuk mewujudkan pembangunan yang berkelanjutan

Influence of physical factors and cultures of microorganisms on segmented polyurethane’s degradation

2016 ◽  
Vol 38 (3) ◽  
pp. 236-243
Author(s):  
L.V. Kobrina ◽  
◽  
V.V. Boiko ◽  
T.V. Dmitrieva ◽  
V.V. Bortnitsky ◽  
...  
Keyword(s):  
Physical Factors
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