scholarly journals Meta-ecosystem dynamics drive the spatial distribution of functional groups in river networks

2021 ◽  
Author(s):  
Claire Jacquet ◽  
Luca Carraro ◽  
Florian Altermatt
Keyword(s):  
Functional Groups ◽  
Ecosystem Model ◽  
Ecosystem Dynamics ◽  
River Networks ◽  
Ecological Communities ◽  
Landscape Matrix ◽  
Central Process ◽  
Stream Communities ◽  
Negative Effect ◽  
Ecosystem Theory

Spatial flow of material and resources is a central process structuring ecological communities. The meta-ecosystem concept provides a theoretical framework to study the interplay between local and regional flows of resources and their implications for ecosystem dynamics and functioning. Yet, meta-ecosystem theory has been applied to highly simplified systems, and the effects of meta-ecosystem dynamics in real-world landscapes, characterized by specific spatial structures, remain largely unexplored. Here, we develop a spatially explicit meta-ecosystem model for dendritic river networks based on a highly realistic landscape matrix. By formalizing a seminal concept in freshwater ecology, we show that the spatial distributions and regional biomass of major functional groups observed in stream communities are determined by specific rates of resource flows. Overall, high rates of resource flow have a negative effect on the regional biomass of all the functional groups studied and can lead to extinctions at the meta-ecosystem scale.

scholarly journals A methodological roadmap to quantify animal-vectored spatial ecosystem subsidies

2020 ◽  
Author(s):  
Diego Ellis-Soto ◽  
Kristy M. Ferraro ◽  
Matteo Rizzuto ◽  
Emily Briggs ◽  
Julia D. Monk ◽  
...  
Keyword(s):  
Animal Movement ◽  
Open Systems ◽  
Nutrient Transport ◽  
Ecosystem Dynamics ◽  
Ecosystem Impacts ◽  
Practical Applications ◽  
Ecosystem Theory ◽  
Spatio Temporal ◽  
High Level ◽  
Tracking Devices

Ecosystems are open systems connected through spatial flows of energy, matter, and nutrients. Predicting and managing ecosystem interdependence requires a rigorous quantitative understanding of the drivers and vectors that connect ecosystems across spatio-temporal scales. Animals act as such vectors when they transport nutrients across landscapes in the form of excreta, egesta, and their own bodies. Here, we introduce a methodological roadmap that combines movement, foraging, and ecosystem ecology to study the effects of animal-vectored nutrient transport on meta-ecosystems. The meta-ecosystem concept — the notion that ecosystems are connected in space and time by flows of energy, matter, and organisms across boundaries — provides a theoretical framework on which to base our understanding of animal-vectored nutrient transport. However, partly due to its high level of abstraction, there are few empirical tests of meta-ecosystem theory, and while we may label animals as important mediators of ecosystem services, we lack predictive inference of their relative roles and impacts on diverse ecosystems. Recently developed technologies and methods — tracking devices, mechanistic movement models, diet reconstruction techniques and remote sensing — have the potential to facilitate the quantification of animal-vectored nutrient flows and increase the predictive power of meta-ecosystem theory. Understanding the mechanisms by which animals shape ecosystem dynamics may be important for ongoing conservation, rewilding, and restoration initiatives around the world, and for more accurate models of ecosystem nutrient budgets. We provide conceptual examples that show how our proposed integration of methodologies could help investigate ecosystem impacts of animal movement. We conclude by describing practical applications to understanding cross-ecosystem contributions of animals on the move.

Bottom-up and top-down effects on phytoplankton functional groups in Hulun Lake, China

2021 ◽  
Vol 57 ◽  
pp. 3
Author(s):  
Chengxue Ma ◽  
Chang Zhao ◽  
Patteson Chula Mwagona ◽  
Ziyu Li ◽  
Zixuan Liu ◽  
...  
Keyword(s):  
Functional Groups ◽  
Phytoplankton Biomass ◽  
Eutrophic Lake ◽  
Positive Influence ◽  
Freshwater Ecosystems ◽  
Top Down ◽  
Bottom Up ◽  
Physical Chemical ◽  
Phytoplankton Functional Groups ◽  
Negative Effect

The debates about the extent to which phytoplankton in freshwater ecosystems are regulated by top-down or bottom-up forces have been ongoing for decades. This study examines the effects of bottom-up and top-down factors on the phytoplankton functional groups in a eutrophic lake. Phytoplankton and zooplankton were sampled and physical-chemical variables measured from May 2019 to October 2019 in Lake Hulun, China. Approximately 43 phytoplankton species were observed and grouped into 23 functional groups. For the zooplankton, about 27 species were observed and classified into 8 functional groups. The study revealed that the bottom-up effects of physical-chemical variables on some phytoplankton functional groups was stronger than the top-down effects of zooplankton. Water temperature (WT), total phosphorus (TP), total nitrogen (TN), conductivity (Cond), water transparency (SD), and dissolved oxygen (DO) significant influence the biomass of the phytoplankton functional groups. The biomass of phytoplankton functional groups was influenced positively by nutrient availability likely because nutrients influence the growth and reproduction of phytoplankton in freshwater. WT and DO had a positive influence on biomass of phytoplankton functional groups. Conversely, phytoplankton biomass revealed a decreasing trend when SD and Cond significantly increased. This study showed that zooplankton functional groups were positively correlated with phytoplankton biomass implying that the top-down control of phytoplankton by the zooplankton in the lake is not strong enough to produce a negative effect. It is evident that the zooplankton functional groups in Lake Hulun are controlled more by bottom-up force than top-down.

How Does Nutrition Structure Ecosystems?

2012 ◽  
Author(s):  
Stephen J. Simpson ◽  
David Raubenheimer
Keyword(s):  
Evolutionary Ecology ◽  
Ecosystem Dynamics ◽  
Trophic Levels ◽  
Nutritional Requirements ◽  
Ecological Communities ◽  
Geometric Framework ◽  
Agent Based ◽  
Fundamental Niche ◽  
Biophysical Ecology ◽  
Ecology Of Nutrition

This chapter assesses the consequences of individual nutrition for populations and the assemblages of species that comprise ecological communities. However, the ecological consequences of nutrition are not restricted to the effects of diet on individual organisms but include as well the direct and indirect interactions occurring among individuals within populations and between species. Understanding the complex network of interactions that produce food webs and structure ecosystem dynamics requires the understanding of the participants' differing nutritional requirements, priorities, and regulatory capacities. Geometric Framework analyses have shown that these features differ between species and across trophic levels. Nutritional space is one part of the fundamental niche of an organism, and there is a need to integrate nutrition with the biophysical ecology of organisms. Evolutionary processes also need to be taken into account, and agent-based models offer promise toward development of a new understanding of the evolutionary ecology of nutrition.

scholarly journals China’s Sharing Economy of Mobility Industry: From Perspective of Industrial Ecosystem

2019 ◽  
Vol 11 (24) ◽  
pp. 7130 ◽  
Author(s):  
Danning Zhang ◽  
Yanshu Shi ◽  
Weiwei Li
Keyword(s):  
Structural Adjustment ◽  
Sharing Economy ◽  
Vital Role ◽  
Third Party ◽  
Ecological Communities ◽  
Profit Model ◽  
The Sustainable Development ◽  
Industrial Ecosystem ◽  
Ecosystem Theory ◽  
Industry Integration

The development of China’s sharing economy has slowed down significantly after experiencing the savage growth since the beginning of 2018 and has entered the turning point of structural adjustment. Factors including homogeneous and single profit model, excessive reliance on capital, and the immaturity of win-win industrial ecosystem are major bottlenecks. Therefore, how to overcome the obstacles is a key issue to be solved urgently. In view of the sharing economy’s characteristics of industry integration and cross-boundary symbiosis, the concept of sharing economy industrial ecosystem was put forward. Furthermore, social network analysis (SNA) was used to solve the problem of weak synergy in the development of China’s sharing economy and strive to break through the development bottleneck in order to realize the optimization of China’s sharing industry ecosystem and the sustainable development of industry. Specially, we proposed a fusion framework of industrial ecosystem and SNA including macro, meso, and micro dimensions. Macro analysis is based on the fusion of ecological environment in ecosystem theory and density analysis in SNA. Meso analysis is based on the fusion of ecological communities in ecosystem theory and subgroup analysis in SNA. Micro analysis is based on the fusion of an ecological niche in ecosystem theory and centrality analysis in SNA. It was found that the ecosystem of sharing mobility industry has been basically established, and the ecological diversity is good, including sharing mobility, third-party platform, automobile manufacturing, insurance and venture capital enterprises and universities. In addition, some sharing enterprises, typically represented by Didi, are upgrading their strategies to ecological development through cross-border integration. Mobile payment plays a vital role in developing China’s sharing mobility industry.

scholarly journals Genetic Variance in the Composition of Two Functional Groups (Diazotrophs and Cyanobacteria) from a Hypersaline Microbial Mat

2006 ◽  
Vol 72 (2) ◽  
pp. 1207-1217 ◽  
Author(s):  
Anthony C. Yannarell ◽  
Timothy F. Steppe ◽  
Hans W. Paerl
Keyword(s):  
Functional Groups ◽  
Seasonal Pattern ◽  
Microbial Mat ◽  
Rrna Gene ◽  
Ecological Communities ◽  
Nitrogen Fixing ◽  
Wet Season ◽  
Overlying Water ◽  
San Salvador ◽  
Dry Conditions

ABSTRACT Examination of variation in ecological communities can lead to an understanding of the forces that structure communities, the consequences of change at the ecosystem level, and the relevant scales involved. This study details spatial and seasonal variability in the composition of nitrogen-fixing and cyanobacterial (i.e., oxygenic photosynthetic) functional groups of a benthic, hypersaline microbial mat from Salt Pond, San Salvador Island, Bahamas. This system shows extreme annual variability in the salinity of the overlying water and the extent of water coverage. Analysis of molecular variance and FST tests of genetic differentiation of nifH and cyanobacterial 16S rRNA gene clone libraries allowed for changes at multiple taxonomic levels (i.e., above, below, and at the species level) to inform the conclusions regarding these functional groups. Composition of the nitrogen-fixing community showed significant seasonal changes related to salinity, while cyanobacterial composition showed no consistent seasonal pattern. Both functional groups exhibited significant spatial variation, changing with depth in the mat and horizontally with distance from the shoreline. The patterns of change suggest that cyanobacterial composition was more insensitive to water stress, and consequently, cyanobacteria dominated the nitrogen-fixing community during dry months but gave way to a more diverse community of diazotrophs in wet months. This seasonal pattern may allow the mat community to respond quickly to water-freshening events after prolonged dry conditions (system recovery) and maintain ecosystem function in the face of disturbance during the wet season (system resilience).

scholarly journals Spatiotemporal variability of abundance size-spectra in streams across North America

2021 ◽  
Author(s):  
Justin Pomeranz ◽  
James R. Junker ◽  
Jeff Wesner
Keyword(s):  
North America ◽  
Environmental Gradients ◽  
Spatiotemporal Variability ◽  
Mean Annual Temperature ◽  
Ecological Communities ◽  
Size Spectra ◽  
Stream Communities ◽  
Continental Scale ◽  
Total Community ◽  
Increasing Temperature

Accepted version of this manuscript can be found here: https://doi.org/10.1111/gcb.15862 The distribution of abundance and biomass within ecological communities is related to trophic transfer efficiency from prey to predators. While it is considered to be one of the few consistent patterns in ecology, spatiotemporal variation of this relationship across continental-scale environmental gradients is unknown. Using a database of stream communities collected across North America (18-68° N latitude, -4 to 25°C mean annual temperature) over 3 years, we constructed 162 mass-abundance relationships (i.e. size spectra). Size-spectra slopes declined (became steeper) with increasing temperature. However, the magnitude of change was relatively small, with median slopes changing from -1.2 to -1.3 across a 29°C range in mean annual temperature. In contrast, total community biomass increased 3-fold over the temperature gradient. Our study suggests strong conservation of abundance size-spectra in streams across broad natural environmental gradients. This supports the emerging use of size-spectra deviations as indicators of ecosystem health.

scholarly journals Species convergence into life-forms in a hyperseasonal cerrado in central Brazil

2008 ◽  
Vol 68 (2) ◽  
pp. 329-339 ◽  
Author(s):  
IA. Silva ◽  
MA. Batalha
Keyword(s):  
Seasonal Variation ◽  
Species Diversity ◽  
Functional Groups ◽  
Life Form ◽  
Experimental Tests ◽  
Water Shortage ◽  
Life Forms ◽  
Ecological Communities ◽  
Central Brazil ◽  
Community Convergence

Whether the functional structure of ecological communities is deterministic or historically contingent is still quite controversial. However, recent experimental tests did not find effects of species composition variation on trait convergence and therefore the environmental constraints should play the major role on community convergence into functional groups. Seasonal cerrados are characterized by a sharp seasonality, in which the water shortage defines the community functioning. Hyperseasonal cerrados experience additionally waterlogging in the rainy season. Here, we asked whether waterlogging modifies species convergences into life-forms in a hyperseasonal cerrado. We studied a hyperseasonal cerrado, comparing it with a nearby seasonal cerrado, never waterlogged, in Emas National Park, central Brazil. In each area, we sampled all vascular plants by placing 40 plots of 1 m² plots in four surveys. We analyzed the species convergences into life-forms in both cerrados using the Raunkiaer's life-form spectrum and the index of divergence from species to life-form diversity (IDD). The overall life-form spectra and IDDs were not different, indicating that waterlogging did not affect the composition of functional groups in the hyperseasonal cerrado. However, there was a seasonal variation in IDD values only in the hyperseasonal cerrado. As long as we did not find a seasonal variation in life-form diversity, the seasonal variation of convergence into life-forms in the hyperseasonal cerrado was a consequence of the seasonal variation of species diversity. Because of high functional redundancy of cerrado plants, waterlogging promoted a floristic replacement without major changes in functional groups. Thus, waterlogging in the hyperseasonal cerrado promoted seasonal changes in species convergence into life-forms by reducing species diversity.

scholarly journals FABM-PCLake – linking aquatic ecology with hydrodynamics

2016 ◽  
Author(s):  
F. Hu ◽  
K. Bolding ◽  
J. Bruggeman ◽  
E. Jeppesen ◽  
M. R. Flindt ◽  
...  
Keyword(s):  
Aquatic Ecosystem ◽  
Light Attenuation ◽  
Ecosystem Model ◽  
Ecosystem Dynamics ◽  
Trophic Levels ◽  
Water Bodies ◽  
Heterogeneous Environments ◽  
Biogeochemical Processes ◽  
Biogeochemical Models ◽  
Wide Range

Abstract. This study presents FABM-PCLake, a complete redesign of the PCLake aquatic ecosystem model, which we implemented into the Framework for Aquatic Biogeochemical Models (FABM). In contrast to the original model, which was designed for temperate, fully mixed freshwater lakes, the new FABM-PCLake represents an integrated aquatic ecosystem model that enables simulations of hydrodynamics and biogeochemical processes for zero dimensional, one-dimensional as well as three-dimensional heterogeneous environments. FABM-PCLake describes interactions between multiple trophic levels, including piscivorous, zooplanktivorous and benthivorous fish, zooplankton, zoobenthos, three groups of phytoplankton and rooted macrophytes. The model also accounts for oxygen dynamics and nutrient cycling for nitrogen, phosphorus and silicon, both within the pelagic and benthic domains. FABM-PCLake includes a two-way communication between the biogeochemical processes and the physics, where some biogeochemical state variables (e.g., phytoplankton) influence light attenuation and thereby the spatial and temporal distributions of light and heat. At the same time, the physical environment, including water currents, light and temperature influence a wide range of biogeochemical processes. The model enables studies on ecosystem dynamics in physically heterogeneous environments (e.g., stratifying water bodies, and water bodies with horizontal gradient in physical and biogeochemical properties), and through FABM also enables data assimilation and multi-model ensemble simulations. Examples of relevant model applications include climate change impact studies and environmental impact assessment scenarios for lakes and reservoirs worldwide.

scholarly journals Environmental heterogeneity promotes spatial resilience of phototrophic biofilms in streambeds

2018 ◽  
Vol 14 (10) ◽  
pp. 20180432
Author(s):  
Katharine Dzubakova ◽  
Hannes Peter ◽  
Enrico Bertuzzo ◽  
Carmelo Juez ◽  
Mário J. Franca ◽  
...  
Keyword(s):  
Structural Equation ◽  
Environmental Heterogeneity ◽  
Growth Trait ◽  
Ecological Communities ◽  
Landscape Matrix ◽  
Spatial Resilience ◽  
Phototrophic Biofilms ◽  
Trait Diversity ◽  
Mobile Links ◽  
Related Trait

The loss of environmental heterogeneity threatens biodiversity and ecosystem functioning. It is therefore important to understand the relationship between environmental heterogeneity and spatial resilience as the capacity of ecological communities embedded in a landscape matrix to reorganize following disturbance. We experimented with phototrophic biofilms colonizing streambed landscapes differing in spatial heterogeneity and exposed to flow-induced disturbance. We show how streambed roughness and related features promote growth-related trait diversity and the recovery of biofilms towards carrying capacity (CC) and spatial resilience. At the scale of streambed landscapes, roughness and exposure to water flow promoted biofilm CC and growth trait diversity. Structural equation modelling identified roughness, post-disturbance biomass and a ‘neighbourhood effect’ to drive biofilm CC. Our findings suggest that the environment selecting for adaptive capacities prior to disturbance (that is, memory effects) and biofilm connectivity into spatial networks (that is, mobile links) contribute to the spatial resilience of biofilms in streambed landscapes. These findings are critical given the key functions biofilms fulfil in streams, now increasingly experiencing shifts in sedimentary and hydrological regimes.

scholarly journals <i>MEDUSA</i>: a new intermediate complexity plankton ecosystem model for the global domain

2010 ◽  
Vol 3 (4) ◽  
pp. 1939-2019 ◽  
Author(s):  
A. Yool ◽  
E. E. Popova ◽  
T. R. Anderson
Keyword(s):  
Deep Ocean ◽  
Ecosystem Model ◽  
Global Scale ◽  
Ecosystem Dynamics ◽  
Global Ocean ◽  
Full Description ◽  
State Variables ◽  
Intermediate Complexity ◽  
Nutrient Utilisation ◽  
Parameter Values

Abstract. The ongoing, anthropogenically-driven changes to the global ocean are expected to have significant consequences for plankton ecosystems in the future. Because of the role that plankton play in the ocean's "biological pump", changes in abundance, distribution and productivity will likely have additional consequences for the wider carbon cycle. Just as in the terrestrial biosphere, marine ecosystems exhibit marked diversity in species and functional types of organisms. Predicting potential change in plankton ecosystems therefore requires the use of models that are suited to this diversity, but whose parameterisation also permits robust and realistic functional behaviour. In the past decade, advances in model sophistication have attempted to address diversity, but have been criticised for doing so inaccurately or ahead of a requisite understanding of underlying processes. Here we introduce MEDUSA (Model of Ecosystem Dynamics, nutrient Utilisation, Sequestration and Acidification), a new "intermediate complexity" plankton ecosystem model that expands on traditional nutrient-phytoplankton-zooplankton-detritus (NPZD) models, and remains amenable to global-scale evaluation. MEDUSA includes the biogeochemical cycles of nitrogen, silicon and iron, broadly structured into "small" and "large" plankton size classes, of which the "large" phytoplankton class is representative of a key phytoplankton group, the diatoms. A full description of MEDUSA's state variables, differential equations, functional forms and parameter values is included, with particular attention focused on the submodel describing the export of organic carbon from the surface to the deep ocean. MEDUSA is used here in a multi-decadal hindcast simulation, and its biogeochemical performance evaluated at the global scale.

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