Biodiversity, Ecosystem Functioning, and Global Change

The impact of interacting global change stressors on terrestrial ecosystems is hard to predict due to non-linear, amplifying, neutral or even buffering interaction effects. We investigated the effects of drought and plant invasion on Mediterranean cork oak (Quercus suber L.) ecosystem functioning and recovery with a combined rain exclusion (30-45 % reduction) and shrub (Cistus ladanifer L.) invasion experiment. As key parameter, we determined tree, shrub and ecosystem transpiration in four treatments: 1) cork oak control stands, 2) cork oaks with rain exclusion, 3) cork oaks invaded by shrubs and 4) cork oaks with rain exclusion and shrub invasion. Rain exclusion and plant invasion led to moderate, but neutral reductions of tree transpiration of 18 % (compared to control) during the mild summer drought in 2018. In 2019, the rain exclusion simulated the second driest year since 1950 for Southwestern (SW) Iberia. The interaction effect of drought and plant invasion was strongly amplifying, reducing tree transpiration by 47 %. Legacy effects on shrubs under the rain exclusion treatment led to a non-linear response during recovery from the severe drought in 2019. Invaded trees showed a delayed transpiration recovery (-51 % vs. control) due to strong competition with shrubs, while invaded trees with rain exclusion recovered to 75 % of the control. This buffering interaction response was caused by a weaker competition from drought-stressed shrubs. Given the projected increase in the frequency, intensity and duration of drought, an increasing non-linear impact on Mediterranean cork oak ecosystems is expected. Our results demonstrate that abiotic stressors modulate biotic interactions thereby impacting ecosystem functioning in a highly dynamic manner. Further efforts are thus needed to model and manage the impact of interacting global change stressors on terrestrial ecosystems.

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Biodiversity and ecosystem functioning in terrestrial habitats of Antarctica

Antarctic Science ◽

10.1017/s0954102005002944 ◽

2005 ◽

Vol 17 (4) ◽

pp. 523-531 ◽

Cited By ~ 35

Author(s):

DIANA H. WALL

Keyword(s):

Global Change ◽

Ecosystem Functioning ◽

Ecosystem Processes ◽

Global Changes ◽

Biodiversity And Ecosystem Functioning ◽

Soil Ecosystems ◽

Terrestrial Habitats ◽

Terrestrial Biodiversity ◽

The Impact ◽

Continental Interior

Are we failing to acknowledge the impact of global changes (e.g. UVB, invasive species, climate, land use, atmosphere) on the terrestrial biodiversity and ecosystem processes of Antarctica? Antarctica is considered a pristine environment and has low terrestrial species diversity and trophic complexity, and yet while scientifically possible, we still do not know the number of species, where they are, or how their influence on ecosystem processes (e.g. nutrient cycling, carbon flux, decomposition, feedbacks to climate, hydrology) will be affected by multiple global changes. Increased recognition of human dependence on services provided by biodiversity and ecosystem functioning combined with documented impacts of global change already occurring on Antarctic soil ecosystems, increases the urgency to expand investigations regionally in Antarctica. We cannot measure the effects of global change or sustainably manage Antarctica's future if we underestimate the contribution of soil communities. Evidence indicates habitats of rocky moraines, soils and cyroconite holes of glaciers in the continental interior may host not only microbes, but also a complexity of algae and invertebrates. Scientists of many disciplines, together, need to assess the benefits humans derive from Antarctic terrestrial biodiversity and ecosystem processes, how these will be affected by global change, and link their findings to the rest of the world.

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Marine archaea and archaeal viruses under global change

F1000Research ◽

10.12688/f1000research.11404.1 ◽

2017 ◽

Vol 6 ◽

pp. 1241 ◽

Cited By ~ 7

Author(s):

Roberto Danovaro ◽

Eugenio Rastelli ◽

Cinzia Corinaldesi ◽

Michael Tangherlini ◽

Antonio Dell'Anno

Keyword(s):

Global Change ◽

Food Web ◽

Ecosystem Functioning ◽

Biogeochemical Cycles ◽

Structure And Function ◽

Food Web Structure ◽

Web Structure ◽

Archaeal Viruses ◽

And Function ◽

Marine Archaea

Global change is altering oceanic temperature, salinity, pH, and oxygen concentration, directly and indirectly influencing marine microbial food web structure and function. As microbes represent >90% of the ocean’s biomass and are major drivers of biogeochemical cycles, understanding their responses to such changes is fundamental for predicting the consequences of global change on ecosystem functioning. Recent findings indicate that marine archaea and archaeal viruses are active and relevant components of marine microbial assemblages, far more abundant and diverse than was previously thought. Further research is urgently needed to better understand the impacts of global change on virus–archaea dynamics and how archaea and their viruses can interactively influence the ocean’s feedbacks on global change.

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For flux’s sake: General considerations for energy-flux calculations in ecological communities

10.22541/au.161407278.80952854/v1 ◽

2021 ◽

Author(s):

Malte Jochum ◽

Andrew Barnes ◽

Ulrich Brose ◽

Benoit Gauzens ◽

Marie Sünnemann ◽

...

Keyword(s):

Global Change ◽

Food Web ◽

Energy Flux ◽

Ecosystem Functioning ◽

Theoretical Background ◽

Ecological Communities ◽

Ecological Research ◽

Trophic Networks ◽

Community Data ◽

Food Web Theory

Global change alters ecological communities with consequences for ecosystem processes. Such processes and functions are a central aspect of ecological research and vital to understanding and mitigating the consequences of global change, but also those of other drivers of change in organism communities. In this context, the concept of energy flux through trophic networks integrates food-web theory and biodiversity-ecosystem functioning theory and connects biodiversity to multitrophic ecosystem functioning. As such, the energy flux approach is a strikingly effective tool to answer central questions in ecology and global-change research. This might seem straight forward, given that the theoretical background and software to efficiently calculate energy flux are readily available. However, the implementation of such calculations is not always straight forward, especially for those who are new to the topic and not familiar with concepts central to this line of research, such as food-web theory or metabolic theory. To facilitate wider use of energy flux in ecological research, we thus provide a guide to adopting energy-flux calculations for people new to the method, struggling with its implementation, or simply looking for background reading, important resources, and standard solutions to the problems everyone faces when starting to quantify energy fluxes for their community data. First, we introduce energy flux and its use in community and ecosystem ecology. Then, we provide a comprehensive explanation of the single steps towards calculating energy flux for community data. Finally, we discuss remaining challenges and exciting research frontiers for future energy-flux research.

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Monitoring Forest Phenology in a Changing World

Forests ◽

10.3390/f12030297 ◽

2021 ◽

Vol 12 (3) ◽

pp. 297

Author(s):

Ross E. J. Gray ◽

Robert M. Ewers

Keyword(s):

Climate Change ◽

Global Change ◽

Spatial Resolution ◽

Ecosystem Functioning ◽

Ecosystem Processes ◽

Plant Phenology ◽

Robust Methods ◽

Monitoring Methods ◽

Trade Offs ◽

Changing World

Plant phenology is strongly interlinked with ecosystem processes and biodiversity. Like many other aspects of ecosystem functioning, it is affected by habitat and climate change, with both global change drivers altering the timings and frequency of phenological events. As such, there has been an increased focus in recent years to monitor phenology in different biomes. A range of approaches for monitoring phenology have been developed to increase our understanding on its role in ecosystems, ranging from the use of satellites and drones to collection traps, each with their own merits and limitations. Here, we outline the trade-offs between methods (spatial resolution, temporal resolution, cost, data processing), and discuss how their use can be optimised in different environments and for different goals. We also emphasise emerging technologies that will be the focus of monitoring in the years to follow and the challenges of monitoring phenology that still need to be addressed. We conclude that there is a need to integrate studies that incorporate multiple monitoring methods, allowing the strengths of one to compensate for the weaknesses of another, with a view to developing robust methods for upscaling phenological observations from point locations to biome and global scales and reconciling data from varied sources and environments. Such developments are needed if we are to accurately quantify the impacts of a changing world on plant phenology.

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