scholarly journals A Functional Perspective for Reef Benthic Communities: Temporal Trends in the Only Atoll in Southern Atlantic

2021 ◽  
Author(s):  
Vitor André Passos Picolotto ◽  
Anaide W. Aued ◽  
Luis C. P. Macedo-Soares ◽  
Julia Biscaia Zamoner ◽  
Bárbara Segal
Keyword(s):  
Benthic Community ◽  
Temporal Dynamics ◽  
Benthic Communities ◽  
Temporal Trends ◽  
Functional Approach ◽  
Functional Ecology ◽  
Ecosystem Functions ◽  
Actual State ◽  
Global Changes ◽  
Functional Richness

Abstract Reef benthic communities provide many important ecosystem functions such as nutrient cycling, carbonate accretion and tridimensional complexity. Yet, reefs worldwide face an uncertain future, being threatened by local and global impacts. As an alternative approach to evaluate communities’ changes, functional ecology aims to understand how species shape the environment and how functions conduct ecosystems’ dynamics. The aim of this study was to investigate the temporal dynamics (2013–2019) of the reef benthic community in the most pristine reef in Brazil, Rocas Atoll, using a functional diversity approach. We identified 48 organisms grouped into 17 functional entities (according to their traits’ combination), considering all sampling years. Benthic community was temporally dominated by functional entities responsible for providing low reef tridimensional complexity (represented mainly by turf algae). This dominance reflected in low values of functional entropy, due to uneven abundances distribution between unique functional entities, those that have unique trait combination. Functional richness oscillated over years, but did not show great changes in functional spaces, maintaining an equity in the number of functional entities and indicating stability of reef functions in Rocas Atoll, even with unequal abundances’ distribution. Our study is the first to use a functional approach in temporal scale and represents a baseline for South Atlantic, since it provides the actual state of reef benthic communities using a functional approach, in an environment with no direct anthropic impacts. This can help to predict the effects on some ecosystem functions caused by local and global changes and its consequence for ecosystem services.

scholarly journals Taxonomic, temporal, and spatial variation in the dynamics of High-Arctic arthropod populations

2020 ◽  
Author(s):  
Toke T. Høye ◽  
Sarah Loboda ◽  
Amanda M. Koltz ◽  
Mark A. K. Gillespie ◽  
Joseph J. Bowden ◽  
...  
Keyword(s):  
Population Dynamics ◽  
Temporal Trends ◽  
Monitoring Program ◽  
High Arctic ◽  
The Arctic ◽  
Taxonomic Resolution ◽  
Ecosystem Functions ◽  
Series Data ◽  
Global Changes ◽  
Apparent Lack

ABSTRACTTime-series data on arthropod populations are critical for understanding the magnitude, direction, and drivers of abundance changes. However, most arthropod monitoring programs are short-lived and limited in taxonomic resolution and spatial extent. Consequently, variation in population dynamics among taxa and habitats remains poorly understood. Monitoring data from the Arctic are particularly underrepresented, yet important to assessments of species abundance changes because many anthropogenic drivers of change that are present in other regions are absent in polar regions. Here, we utilise 24 years of abundance data from Zackenberg in High-Arctic Greenland, which is the longest running Arctic arthropod monitoring program, to study temporal trends in abundance. Despite a strong warming signal in air temperature, we only find evidence of weak temporal trends in arthropod abundances across most taxa. These trends are more pronounced in the most recent decade, with change point analyses suggesting distinct non-linear dynamics within some functional groups such as predators and detritivores. Although the abundances of many taxa were correlated, we detected both positive and negative correlations, suggesting that multiple processes are affecting arthropod populations even in this relatively simple Arctic food web. Finally, we found clear differences among species within single families of arthropods, indicating that an apparent lack of change in abundance at broader taxonomic or functional levels could mask substantial species-specific trends. Our results reiterate the need for more basic research into the life-history, ecology, and adaptation of arthropod species to better understand their sensitivity to global changes.Significance statementTerrestrial arthropods, including insects and spiders, serve critical ecosystem functions and are excellent indicators of environmental change due to their physiology, short generation time, and abundance. The Arctic, with its rapid climate change and limited direct anthropogenic impact, is ideal for examining arthropod population dynamics. We use the most comprehensive, standardized dataset available on Arctic arthropods to evaluate the variability in population dynamics for the most common arthropod groups at various taxonomic levels across 24 years. Our results highlight that temporal trends of arthropod populations seem less directional in the Arctic than in temperate regions. Although abundances of some arthropod taxa are declining, particularly in recent decades, population trends still display high variation among time periods, taxa, and habitats.

scholarly journals Methodology for classifying the ecosystem integrity of forests in Germany using quantified indicators

2021 ◽  
Vol 33 (1) ◽  
Author(s):  
Martin Jenssen ◽  
Stefan Nickel ◽  
Winfried Schröder
Keyword(s):  
Climate Change ◽  
National Park ◽  
Temporal Trends ◽  
Water Flux ◽  
Ecosystem Functions ◽  
Specific Reference ◽  
Atmospheric Nitrogen ◽  
Complete Coverage ◽  
Ecosystem Integrity ◽  
Quantitative Indicators

Abstract Background Atmospheric deposition of nitrogen and climate change can have impacts on ecological structures and functions, and thus on the integrity of ecosystems and their services. Operationalization of ecosystem integrity is still an important desideratum. Results A methodology for classifying the ecosystem integrity of forests in Germany under the influence of climate change and atmospheric nitrogen deposition is presented. The methodology was based on 14 indicators for six ecosystem functions: habitat function, net primary function, carbon sequestration, nutrient and water flux, resilience. It allows assessments of ecosystem integrity changes by comparing current or prospective ecosystem states with ecosystem-type-specific reference states as described by quantitative indicators for 61 forest ecosystem types based on data before 1990. Conclusion The method developed enables site-specific classifications of ecosystem integrity as well as classifications with complete coverage and determinations of temporal trends as shown using examples from the Thuringian Forest and the “Kellerwald-Edersee” National Park (Germany).

scholarly journals A three-dimensional view on biodiversity changes: spatial, temporal, and functional perspectives on fish communities in the Baltic Sea

2018 ◽  
Vol 75 (7) ◽  
pp. 2463-2475 ◽  
Author(s):  
Romain Frelat ◽  
Alessandro Orio ◽  
Michele Casini ◽  
Andreas Lehmann ◽  
Bastien Mérigot ◽  
...  
Keyword(s):  
Baltic Sea ◽  
Environmental Conditions ◽  
Environmental Changes ◽  
Temporal Dynamics ◽  
Marine Ecosystem ◽  
Fish Communities ◽  
The Baltic Sea ◽  
Functional Richness ◽  
Holistic Understanding ◽  
The Baltic

Abstract Fisheries and marine ecosystem-based management requires a holistic understanding of the dynamics of fish communities and their responses to changes in environmental conditions. Environmental conditions can simultaneously shape the spatial distribution and the temporal dynamics of a population, which together can trigger changes in the functional structure of communities. Here, we developed a comprehensive framework based on complementary multivariate statistical methodologies to simultaneously investigate the effects of environmental conditions on the spatial, temporal and functional dynamics of species assemblages. The framework is tested using survey data collected during more than 4000 fisheries hauls over the Baltic Sea between 2001 and 2016. The approach revealed the Baltic fish community to be structured into three sub-assemblages along a strong and temporally stable salinity gradient decreasing from West to the East. Additionally, we highlight a mismatch between species and functional richness associated with a lower functional redundancy in the Baltic Proper compared with other sub-areas, suggesting an ecosystem more susceptible to external pressures. Based on a large dataset of community data analysed in an innovative and comprehensive way, we could disentangle the effects of environmental changes on the structure of biotic communities—key information for the management and conservation of ecosystems.

scholarly journals Getis-Ord Gi* statistics for hydrocarbons content analysis in the Tromjegan river basin

2020 ◽  
Vol 26 (2) ◽  
pp. 151-160
Author(s):  
Valentina Dobryakova ◽  
Natalya Moskvina ◽  
Andrey Dobryakov ◽  
Lilia Zhegalina ◽  
Ildar Idrisov
Keyword(s):  
Environmental Monitoring ◽  
River Basin ◽  
Surface Waters ◽  
Temporal Dynamics ◽  
Hot Spot ◽  
Temporal Trends ◽  
Environmental Research ◽  
Analysis Tool ◽  
Hydrocarbon Pollution ◽  
Average Maximum

The information content and effectiveness of ecological research of the territory can be improved using the methods of multivariate analysis and mapping of the results. The article presents the analysis and mapping results of spatial and temporal trends of hydrocarbon pollution in the Tromjegan river basin for the period 2006–2018 using the tools of ArcGIS Pro. The informational and basic research is the data of local environmental monitoring of licensed blocks of the Khanty-Mansiysk Autonomous Okrug — Ugra. Pollution analysis was carried out on the basis of a detailed study of the geography of the source data using statistical calculations (minimum, average, maximum distances between sampling points, Getis-Ord Gi* index). Thematic maps were constructed using data averaged over the year. The spatial and temporal dynamics of hydrocarbons concentration in surface waters for 2006–2018 is analyzed using the “Hot Spot Analysis” tool. A temporary cluster section of hydrocarbons average annual concentration according to the Getis-Ord Gi* indicator allowed us to identify trends in the dynamics of indicators. Maps of hydrocarbons average annual concentration were compiled and the results of a spatial-temporal analysis of hydrocarbons average annual concentration in surface waters were presented. The identification of patterns in large arrays of long-term data and the consideration of the spatial component are necessary elements of modern environmental research. Analysis of the time series of average annual concentrations in the Tromjegan river basin showed a clear trend in the dynamics of hydrocarbon pollution. The findings can be the basis for making managerial decisions in the environmental monitoring of licensed blocks of the Khanty-Mansiysk Autonomous Okrug — Ugra.

Predicting change in biogeochemical potential of subsurface systems with changing hydrogeological conditions

2021 ◽  
Author(s):  
Swamini Khurana ◽  
Falk Heße ◽  
Martin Thullner
Keyword(s):  
Water Quality ◽  
Preferential Flow ◽  
Nutrient Loading ◽  
Temporal Dynamics ◽  
Reaction Network ◽  
Climate Scenario ◽  
Ecosystem Functions ◽  
External Forcing ◽  
Spatio Temporal ◽  
The Impact

<p>In a changing climate scenario, we expect weather event patterns to change, both in frequency and in intensity. The subsequent impacts of these changing patterns on ecosystem functions are of great interest. Water quality particularly is critical due to public health concerns. Already, seasonal variation of water quality has been attributed to varying microbial community assemblages and nutrient loading in the corresponding water body but the contribution of the variations in the quantity of groundwater recharge is a missing link. It is thus beneficial to establish links between external forcing such as changing infiltration rate or recharge on nutrient cycling in the subsurface. We undertake this study to investigate the impact of temporal variation in external forcing on the biogeochemical potential of spatially heterogeneous subsurface systems using a numerical modeling approach. We used geostatistical tools to generate spatial random fields by considering difference combinations of the variance in the log conductivity field and the anisotropy of the domain. Tuning these two parameters assists in effective representation of a wide variety of geologic materials with varying intensity of preferential flow paths in the heterogeneous domain. We ran simulations using OGS#BRNS that enables us to combine a flexibly defined microbial mediated reaction network with the mentioned spatially heterogeneous domains in transient conditions. We propose that a combination of estimated field indicators of Damköhler number, Peclet number (transformed Damköhler number: Da<sub>t</sub>), and projected temporal dynamics in surface conditions can assist us in predicting the change in biogeochemical potential of the subsurface system. Preliminary results indicate that we miss potentially critical variations in reactive species concentration if we neglect spatio-temporal heterogeneities for regimes where 1<Da<sub>t</sub><40. For regimes characterized by values outside this range, we propose that spatio-temporal heterogeneities due to subsurface structure and changing hydrological forcing may not be relevant.</p>

scholarly journals Spatio-Temporal Patterns of the 2019-nCoV Epidemic at the County Level in Hubei Province, China

2020 ◽  
Vol 17 (7) ◽  
pp. 2563 ◽  
Author(s):  
Wentao Yang ◽  
Min Deng ◽  
Chaokui Li ◽  
Jincai Huang
Keyword(s):  
Temporal Dynamics ◽  
Spatial Interaction ◽  
Temporal Trends ◽  
Temporal Patterns ◽  
Temporal Analysis ◽  
Hubei Province ◽  
Incidence Rates ◽  
County Level ◽  
Spatial Clusters ◽  
Spatio Temporal

Understanding the spatio-temporal characteristics or patterns of the 2019 novel coronavirus (2019-nCoV) epidemic is critical in effectively preventing and controlling this epidemic. However, no research analyzed the spatial dependency and temporal dynamics of 2019-nCoV. Consequently, this research aims to detect the spatio-temporal patterns of the 2019-nCoV epidemic using spatio-temporal analysis methods at the county level in Hubei province. The Mann–Kendall and Pettitt methods were used to identify the temporal trends and abrupt changes in the time series of daily new confirmed cases, respectively. The local Moran’s I index was applied to uncover the spatial patterns of the incidence rate, including spatial clusters and outliers. On the basis of the data from January 26 to February 11, 2020, we found that there were 11 areas with different types of temporal patterns of daily new confirmed cases. The pattern characterized by an increasing trend and abrupt change is mainly attributed to the improvement in the ability to diagnose the disease. Spatial clusters with high incidence rates during the period were concentrated in Wuhan Metropolitan Area due to the high intensity of spatial interaction of the population. Therefore, enhancing the ability to diagnose the disease and controlling the movement of the population can be confirmed as effective measures to prevent and control the regional outbreak of the epidemic.

scholarly journals Nutrient pollution disrupts key ecosystem functions on coral reefs

2018 ◽  
Vol 285 (1880) ◽  
pp. 20172718 ◽  
Author(s):  
Nyssa J. Silbiger ◽  
Craig E. Nelson ◽  
Kristina Remple ◽  
Jessica K. Sevilla ◽  
Zachary A. Quinlan ◽  
...  
Keyword(s):  
Coral Reefs ◽  
Nutrient Addition ◽  
Ecosystem Functions ◽  
Nutrient Pollution ◽  
Global Changes ◽  
Ambient Conditions ◽  
Net Community Production ◽  
Saturation State ◽  
Indirect Response ◽  
The Impact

There is a long history of examining the impacts of nutrient pollution and pH on coral reefs. However, little is known about how these two stressors interact and influence coral reef ecosystem functioning. Using a six-week nutrient addition experiment, we measured the impact of elevated nitrate (NO − 3 ) and phosphate (PO 3− 4 ) on net community calcification (NCC) and net community production (NCP) rates of individual taxa and combined reef communities. Our study had four major outcomes: (i) NCC rates declined in response to nutrient addition in all substrate types, (ii) the mixed community switched from net calcification to net dissolution under medium and high nutrient conditions, (iii) nutrients augmented pH variability through modified photosynthesis and respiration rates, and (iv) nutrients disrupted the relationship between NCC and aragonite saturation state documented in ambient conditions. These results indicate that the negative effect of NO − 3 and PO 3− 4 addition on reef calcification is likely both a direct physiological response to nutrients and also an indirect response to a shifting pH environment from altered NCP rates. Here, we show that nutrient pollution could make reefs more vulnerable to global changes associated with ocean acidification and accelerate the predicted shift from net accretion to net erosion.

scholarly journals Uncovering the environmental drivers of short-term temporal dynamics in an epibenthic community from the Western English Channel

2019 ◽  
Vol 99 (7) ◽  
pp. 1467-1479
Author(s):  
Elizabeth Talbot ◽  
Jorn Bruggeman ◽  
Chris Hauton ◽  
Stephen Widdicombe
Keyword(s):  
Time Series Data ◽  
Temporal Dynamics ◽  
Anthropogenic Impacts ◽  
Benthic Communities ◽  
Food Limitation ◽  
Environmental Drivers ◽  
Sediment Surface ◽  
Series Data ◽  
English Channel ◽  
Larval Recruitment

AbstractBenthic communities, critical to the health and function of marine ecosystems, are under increasing pressure from anthropogenic impacts such as pollution, eutrophication and climate change. In order to refine predictions of likely future changes in benthic communities resulting from these impacts, we must first better constrain their responses to natural seasonality in environmental conditions. Epibenthic time series data (July 2008–May 2014) have been collected from Station L4, situated 7.25 nautical miles south of Plymouth in the Western English Channel. These data were analysed to establish patterns in community abundance, wet biomass and composition, and to link any observed patterns to environmental variables. A clear response to the input of organic material from phytoplankton blooms was detected, with sediment surface living deposit feeders showing an immediate increase in abundance, while predators and scavengers responded later, with an increase in biomass. We suggest that this response is a result of two factors. The low organic content of the L4 sediment results in food limitation of the community, and the mild winter/early spring bottom water temperatures allow the benthos to take immediate advantage of bloom sedimentation. An inter-annual change in community composition was also detected, as the community shifted from one dominated by the anomuran Anapagurus laevis to one dominated by the gastropod Turitella communis. This appeared to be related to a period of high larval recruitment for T. communis in 2013/2014, suggesting that changes in the recruitment success of one species can affect the structure of an entire community.

scholarly journals Depth moderates loss of marine foundation species after an extreme marine heatwave: could deep temperate reefs act as a refuge?

2020 ◽  
Vol 287 (1928) ◽  
pp. 20200709
Author(s):  
Ana Giraldo-Ospina ◽  
Gary A. Kendrick ◽  
Renae K. Hovey
Keyword(s):  
Transition Zone ◽  
Community Composition ◽  
Benthic Community ◽  
Benthic Communities ◽  
Foundation Species ◽  
Temperate Reefs ◽  
Environmental Extremes ◽  
Deep Reefs ◽  
Clear Shift ◽  
Western Australian

Marine heatwaves (MHWs) have been documented around the world, causing widespread mortality of numerous benthic species on shallow reefs (less than 15 m depth). Deeper habitats are hypothesized to be a potential refuge from environmental extremes, though we have little understanding of the response of deeper benthic communities to MHWs. Here, we show how increasing depth moderates the response of seaweed- and coral-dominated benthic communities to an extreme MHW across a subtropical–temperate biogeographical transition zone. Benthic community composition and key habitat-building species were characterized across three depths (15, 25 and 40 m) before and several times after the 2011 Western Australian MHW to assess resistance during and recovery after the heatwave. We found high natural variability in benthic community composition along the biogeographic transition zone and across depths with a clear shift in the composition after the MHW in shallow (15 m) sites but a lot less in deeper communities (40 m). Most importantly, key habitat-building seaweeds such as Ecklonia radiata and Syctothalia dorycarpa which had catastrophic losses on shallow reefs, remained and were less affected in deeper communities. Evidently, deep reefs have the potential to act as a refuge during MHWs for the foundation species of shallow reefs in this region.

scholarly journals Global change in the functional diversity of marine fisheries exploitation over the past 65 years

2020 ◽  
Vol 287 (1933) ◽  
pp. 20200889 ◽  
Author(s):  
Isaac Trindade-Santos ◽  
Faye Moyes ◽  
Anne E. Magurran
Keyword(s):  
Functional Diversity ◽  
Functional Divergence ◽  
Marine Ecosystem ◽  
Temporal Trends ◽  
Functional Trait ◽  
Marine Fisheries ◽  
Large Marine Ecosystems ◽  
The Past ◽  
Functional Richness ◽  
Spatial And Temporal Trends

Overexploitation is recognized as one of the main threats to global biodiversity. Here, we report a widespread change in the functional diversity of fisheries catches from the large marine ecosystems (LMEs) of the world over the past 65 years (1950 to 2014). The spatial and temporal trends of functional diversity exploited from the LMEs were calculated using global reconstructed marine fisheries catch data provided by the Sea Around Us initiative (including subsistence, artisanal, recreational, industrial fisheries, and discards) and functional trait data available in FishBase. Our analyses uncovered a substantial increase in the functional richness of both ray-finned fishes (80% of LMEs) and cartilaginous species (sharks and rays) (75% of LMESs), in line with an increase in the taxonomic richness, extracted from these ecosystems. The functional evenness and functional divergence of these catches have also altered substantially over the time span of this study, with considerable geographic variation in the patterns detected. These trends show that global fisheries are increasingly targeting species that play diverse roles within the marine ecosystem and underline the importance of incorporating functional diversity in ecosystem management.

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