Physiology of the Nitrite-Oxidizing Bacterium Candidatus Nitrotoga sp. CP45 Enriched From a Colorado River

Nitrogen cycling microbes, including nitrite-oxidizing bacteria (NOB), perform critical ecosystem functions that help mitigate anthropogenic stresses and maintain ecosystem health. Activity of these beneficial nitrogen cycling microbes is dictated in part by the microorganisms’ response to physicochemical conditions, such as temperature, pH, and nutrient availability. NOB from the newly described Candidatus Nitrotoga genus have been detected in a wide range of habitats across the globe, yet only a few organisms within the genus have been physiologically characterized. For freshwater systems where NOB are critical for supporting aquatic life, Ca. Nitrotoga have been previously detected but little is known about the physiological potential of these organisms or their response to changing environmental conditions. Here, we determined functional response to environmental change for a representative freshwater species of Ca. Nitrotoga (Ca. Nitrotoga sp. CP45, enriched from a Colorado river). The physiological findings demonstrated that CP45 maintained nitrite oxidation at pH levels of 5–8, at temperatures from 4 to 28°C, and when incubated in the dark. Light exposure and elevated temperature (30°C) completely halted nitrite oxidation. Ca. Nitrotoga sp. CP45 maintained nitrite oxidation upon exposure to four different antibiotics, and potential rates of nitrite oxidation by river sediment communities were also resilient to antibiotic stress. We explored the Ca. Nitrotoga sp. CP45 genome to make predictions about adaptations to enable survival under specific conditions. Overall, these results contribute to our understanding of the versatility of a representative freshwater Ca. Nitrotoga sp. Identifying the specific environmental conditions that maximize NOB metabolic rates may ultimately direct future management decisions aimed at restoring impacted systems.

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Strategies and adaptations to aquatic life at high altitude

10.1093/oso/9780198736868.003.0005 ◽

2017 ◽

Author(s):

Dean Jacobsen ◽

Olivier Dangles

Keyword(s):

High Altitude ◽

Environmental Conditions ◽

Low Temperatures ◽

Cold Adaptation ◽

Inorganic Carbon ◽

Direct Result ◽

Aquatic Life ◽

Dissolved Carbon ◽

Dissolved Carbon Dioxide ◽

Regulatory Capacity

Chapter 5 is focused on how organisms cope with the environmental conditions that are a direct result of high altitude. Organisms reveal a number of fascinating ways of dealing with a life at high altitude; for example, avoidance and pigmentation as protection against damaging high levels of ultraviolet radiation, accumulation of antifreeze proteins, and metabolic cold adaptation among species encountering low temperatures with the risk of freezing, oxy-regulatory capacity in animals due to low availability of oxygen, and root uptake from the sediment of inorganic carbon by plants living in waters poor in dissolved carbon dioxide. These and more adaptations are carefully described through a number of examples from famous flagship species in addition to the less well-known ones. Harsh environmental conditions work as an environmental filter that only allows the well-adapted species to slip through to colonize high altitude waters.

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Morphological Variations of Wild Populations of Brycon dentex (Characidae, Teleostei) in the Guayas Hydrographic Basin (Ecuador). The Impact of Fishing Policies and Environmental Conditions

Animals ◽

10.3390/ani11071901 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1901

Author(s):

Ana Gonzalez-Martinez ◽

Carmen De-Pablos-Heredero ◽

Martin González ◽

Jorge Rodriguez ◽

Cecilio Barba ◽

...

Keyword(s):

Discriminant Analysis ◽

Environmental Conditions ◽

Anthropogenic Activity ◽

Freshwater Species ◽

Fishing Pressure ◽

Wild Populations ◽

Morphometric Variation ◽

Morphological Variations ◽

Body Development ◽

The Impact

The Guayas, located in Ecuador, is the largest basin in the Pacific Ocean and has an inventory of 123 native freshwater species. Most of these are endemic species that are threatened or at-risk due to anthropogenic activity and the modification, fragmentation, and destruction of habitats. The aim of this study was to determine the morphometric variation in three wild populations of Brycon dentex in the Guayas basin rivers and their connections to fishing management and environmental conditions. A total of 200 mature fish were captured, and 26 morphometric parameters were measured. The fishing policies (Hypothesis 1) and environmental conditions (Hypothesis 2) were considered fixed factors and were validated by t-tests. The morphological variation among the three populations (Hypothesis 3) was validated through a discriminant analysis. Fishing policies and resource management were found to generate morphological differences associated with body development. In addition, the environmental conditions were found to influence the size and structure of Brycon dentex populations. The analyzed populations were discriminated by the generated morphometric models, which differentiated Cluster 1 (Quevedo and Mocache rivers) with high fishing pressure from Cluster 2 (Pintado river) with medium–low fishing pressure. Morphometric differentiation by discriminant analysis is a direct and economic methodology that can be applied as an indicator of diversity maintenance.

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Quantifying Understory Complexity in Unmanaged Forests Using TLS and Identifying Some of Its Major Drivers

Remote Sensing ◽

10.3390/rs13081513 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1513

Author(s):

Dominik Seidel ◽

Peter Annighöfer ◽

Christian Ammer ◽

Martin Ehbrecht ◽

Katharina Willim ◽

...

Keyword(s):

Laser Scanning ◽

Structural Equation Models ◽

Light Availability ◽

Structural Complexity ◽

Basal Area ◽

Ecosystem Functions ◽

Canopy Openness ◽

Seasonal Precipitation ◽

Wide Range ◽

Precipitation And Temperature

The structural complexity of the understory layer of forests or shrub layer vegetation in open shrublands affects many ecosystem functions and services provided by these ecosystems. We investigated how the basal area of the overstory layer, annual and seasonal precipitation, annual mean temperature, as well as light availability affect the structural complexity of the understory layer along a gradient from closed forests to open shrubland with only scattered trees. Using terrestrial laser scanning data and the understory complexity index (UCI), we measured the structural complexity of sites across a wide range of precipitation and temperature, also covering a gradient in light availability and basal area. We found significant relationships between the UCI and tree basal area as well as canopy openness. Structural equation models (SEMs) confirmed significant direct effects of seasonal precipitation on the UCI without mediation through basal area or canopy openness. However, annual precipitation and temperature effects on the UCI are mediated through canopy openness and basal area, respectively. Understory complexity is, despite clear dependencies on the available light and overall stand density, significantly and directly driven by climatic parameters, particularly the amount of precipitation during the driest month.

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Analysis of high yielding maize production - a study based on a commercial crop

Australian Journal of Experimental Agriculture ◽

10.1071/ea06103 ◽

2008 ◽

Vol 48 (3) ◽

pp. 296 ◽

Cited By ~ 5

Author(s):

C. J. Birch ◽

G. McLean ◽

A. Sawers

Keyword(s):

Retrospective Analysis ◽

Environmental Conditions ◽

Sowing Date ◽

Plant Population ◽

Higher Plant ◽

Maize Crop ◽

Wide Range ◽

Commercial Crop ◽

Reduced Temperature

This paper reports on the use of APSIM – Maize for retrospective analysis of performance of a high input, high yielding maize crop and analysis of predicted performance of maize grown with high inputs over the long-term (>100 years) for specified scenarios of environmental conditions (temperature and radiation) and agronomic inputs (sowing date, plant population, nitrogen fertiliser and irrigation) at Boort, Victoria, Australia. It uses a high yielding (17 400 kg/ha dry grain, 20 500 kg/ha at 15% water) commercial crop grown in 2004–05 as the basis of the study. Yield for the agronomic and environmental conditions of 2004–05 was predicted accurately, giving confidence that the model could be used for the detailed analyses undertaken. The analysis showed that the yield achieved was close to that possible with the conditions and agronomic inputs of 2004–05. Sowing dates during 21 September to 26 October had little effect on predicted yield, except when combined with reduced temperature. Single year and long-term analyses concluded that a higher plant population (11 plants/m2) is needed to optimise yield, but that slightly lower N and irrigation inputs are appropriate for the plant population used commercially (8.4 plants/m2). Also, compared with changes in agronomic inputs increases in temperature and/or radiation had relatively minor effects, except that reduced temperature reduces predicted yield substantially. This study provides an approach for the use of models for both retrospective analysis of crop performance and assessment of long-term variability of crop yield under a wide range of agronomic and environmental conditions.

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ASSESSING ENVIRONMENTAL IMPACTS DURING NATURAL DISASTER: THE DEVELOPMENT OF A RAPID ENVIRONMENTAL ASSESSMENT METHODOLOGY

Journal of Environmental Assessment Policy and Management ◽

10.1142/s1464333202001157 ◽

2002 ◽

Vol 04 (04) ◽

pp. 475-492 ◽

Cited By ~ 3

Author(s):

CHARLES KELLY

Keyword(s):

Environmental Impact ◽

Impact Assessment ◽

Environmental Impact Assessment ◽

Environmental Conditions ◽

Environmental Damage ◽

Assessment Procedure ◽

Disaster Victims ◽

Wide Range ◽

Negative Impacts ◽

The Impact

The linkages between disaster and environmental damage are recognized as important to predicting, preventing and mitigating the impact of disasters. Environmental Impact Assessment (EIA) procedures are well developed for non-ndisaster situations. However, they are conceptually and operationally inappropriate for use in disaster conditions, particularly in the first 120 days after the disaster has begun. The paper provides a conceptual overview of the requirements for an environmental impact assessment procedure appropriate for disaster conditions. These requirements are captured in guidelines for a Rapid Environmental Impact Assessment (REA) for use in disasters. The REA guides the collection and assessment of a wide range of factors which can indicate: (1) the negative impacts of a disaster on the environment, (2) the impacts of environmental conditions on the magnitude of a disaster and, (3) the positive or negative impacts of relief efforts on environmental conditions. The REA also provides a foundation for recovery program EIAs, thus improving the overall post disaster recovery process. The REA is designed primarily for relief cadres, but is also expected to be usable as an assessment tool with disaster victims. The paper discusses the field testing of the REA under actual disaster conditions.

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Ozone damage, detoxification and the role of isoprenoids – new impetus for integrated models

Functional Plant Biology ◽

10.1071/fp15302 ◽

2016 ◽

Vol 43 (4) ◽

pp. 324 ◽

Cited By ~ 15

Author(s):

Supriya Tiwari ◽

Rüdiger Grote ◽

Galina Churkina ◽

Tim Butler

Keyword(s):

Stomatal Conductance ◽

Environmental Conditions ◽

Economic Losses ◽

Plant Responses ◽

Damage Scenarios ◽

Biochemical Processes ◽

Wide Range ◽

Defence Responses ◽

High Concentrations ◽

The Impact

High concentrations of ozone (O3) can have significant impacts on the health and productivity of agricultural and forest ecosystems, leading to significant economic losses. In order to estimate this impact under a wide range of environmental conditions, the mechanisms of O3 impacts on physiological and biochemical processes have been intensively investigated. This includes the impact on stomatal conductance, the formation of reactive oxygen species and their effects on enzymes and membranes, as well as several induced and constitutive defence responses. This review summarises these processes, discusses their importance for O3 damage scenarios and assesses to which degree this knowledge is currently used in ecosystem models which are applied for impact analyses. We found that even in highly sophisticated models, feedbacks affecting regulation, detoxification capacity and vulnerability are generally not considered. This implies that O3 inflicted alterations in carbon and water balances cannot be sufficiently well described to cover immediate plant responses under changing environmental conditions. Therefore, we suggest conceptual models that link the depicted feedbacks to available process-based descriptions of stomatal conductance, photosynthesis and isoprenoid formation, particularly the linkage to isoprenoid models opens up new options for describing biosphere-atmosphere interactions.

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Distribution, feeding behaviour, and condition of Cape horse mackerel early life stages, Trachurus capensis, under different environmental conditions in the northern Benguela upwelling ecosystem

ICES Journal of Marine Science ◽

10.1093/icesjms/fsu087 ◽

2014 ◽

Vol 72 (2) ◽

pp. 543-557 ◽

Cited By ~ 3

Author(s):

S. J. Geist ◽

A. Kunzmann ◽

H. M. Verheye ◽

A. Eggert ◽

A. Schukat ◽

...

Keyword(s):

Dissolved Oxygen ◽

Feeding Ecology ◽

Environmental Conditions ◽

Early Life ◽

Early Life History ◽

Horse Mackerel ◽

Larval Phase ◽

Recruitment Success ◽

Wide Range ◽

Variable Recruitment

Abstract Early life history (ELH) traits are key to understand variable recruitment success and hence the stock size of marine fish. One of the currently most puzzling ecosystems in this regard is the northern part of the Benguela Current upwelling system off Namibia. Here, populations of the formerly dominant pelagic species, sardine and anchovy, failed to recover during the last three decades after a dramatic decline. In contrast, Cape horse mackerel, Trachurus capensis, maintained a constant population size. Warming of the system and shoaling of hypoxic zones together with feedback loops within an altered foodweb are discussed to be responsible for this regime shift. In this study, we address the role of larval traits for the successful performance of the T. capensis population under the present environmental conditions with the focus on feeding ecology. We investigated seasonal variations of the geographical distribution, growth rate, feeding ecology, and nutritional condition of their ELH stages and examined relationships with water temperature, dissolved oxygen concentration, and micro-zooplankton composition. T. capensis' ELH stages showed a wide spatial and seasonal distribution, a preference for higher water temperatures (18–21°C) and presence over a wide range of dissolved oxygen concentrations (0.13–6.35 ml O2 l−1). Feeding success was high and mainly different groups of Copepoda were targeted, which were strongly size selected. The high dietary importance of micro-copepods during large parts of the larval phase indicates successful exploitation of this food source, which has increased in abundance during the last decade. It also explains observed best nutritional conditions at temperatures between 18 and 21°C, since these small copepods are commonly associated with warmer temperatures. Altogether, these traits enhance the species' probability to encounter suitable environments for the survival of their ELH stages, which is likely to lead to their high recruitment success in the northern Benguela ecosystem.

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Urochloa platyphylla (broadleaf signalgrass).

10.1079/cpc.9669.20210099877 ◽

2021 ◽

Author(s):

Julissa Rojas-Sandoval ◽

Pedro Acevedo-Rodríguez

Keyword(s):

Environmental Conditions ◽

Crop Residue ◽

Soil Surface ◽

Grass Species ◽

Crop Fields ◽

Wide Range ◽

Germinating Seeds

Abstract U. platyphylla is a weedy grass species commonly found in disturbed, open and sandy sites such as crop fields, ditches and roadsides. It is considered a troublesome weed because of its tolerance to some herbicides principally in maize plantations (Chamblee et al., 1982; Gallaher et al.,1999). U. platyphylla is highly adaptable and it is able to germinate and grow throughout a wide range of soil and environmental conditions (Burke et al., 2003). Additionally, its seeds may remain on the crop residue until pre-emergence herbicides are no longer effective in controlling the germinating seeds, at which time the seeds fall to the soil surface and germinate (Alford et al., 2005).

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Separating damage from environmental effects affecting civil structures for near real-time damage detection

Structural Health Monitoring ◽

10.1177/1475921717722060 ◽

2017 ◽

Vol 17 (4) ◽

pp. 850-868 ◽

Cited By ~ 7

Author(s):

William Soo Lon Wah ◽

Yung-Tsang Chen ◽

Gethin Wyn Roberts ◽

Ahmed Elamin

Keyword(s):

Damage Detection ◽

Real Time ◽

Environmental Effects ◽

Environmental Conditions ◽

Principal Component ◽

Detection Methods ◽

Real Time Monitoring ◽

Civil Structures ◽

Data Set ◽

Wide Range

Analyzing changes in vibration properties (e.g. natural frequencies) of structures as a result of damage has been heavily used by researchers for damage detection of civil structures. These changes, however, are not only caused by damage of the structural components, but they are also affected by the varying environmental conditions the structures are faced with, such as the temperature change, which limits the use of most damage detection methods presented in the literature that did not account for these effects. In this article, a damage detection method capable of distinguishing between the effects of damage and of the changing environmental conditions affecting damage sensitivity features is proposed. This method eliminates the need to form the baseline of the undamaged structure using damage sensitivity features obtained from a wide range of environmental conditions, as conventionally has been done, and utilizes features from two extreme and opposite environmental conditions as baselines. To allow near real-time monitoring, subsequent measurements are added one at a time to the baseline to create new data sets. Principal component analysis is then introduced for processing each data set so that patterns can be extracted and damage can be distinguished from environmental effects. The proposed method is tested using a two-dimensional truss structure and validated using measurements from the Z24 Bridge which was monitored for nearly a year, with damage scenarios applied to it near the end of the monitoring period. The results demonstrate the robustness of the proposed method for damage detection under changing environmental conditions. The method also works despite the nonlinear effects produced by environmental conditions on damage sensitivity features. Moreover, since each measurement is allowed to be analyzed one at a time, near real-time monitoring is possible. Damage progression can also be given from the method which makes it advantageous for damage evolution monitoring.

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