scholarly journals Parsing human and biophysical drivers of coral reef regimes

2019 ◽  
Vol 286 (1896) ◽  
pp. 20182544 ◽  
Author(s):  
Jean-Baptiste Jouffray ◽  
Lisa M. Wedding ◽  
Albert V. Norström ◽  
Mary K. Donovan ◽  
Gareth J. Williams ◽  
...  
Keyword(s):  
Coral Reef ◽  
Global Climate Change ◽  
Global Climate ◽  
Benthic Communities ◽  
Social Processes ◽  
Natural Setting ◽  
Effective Management ◽  
Management Interventions ◽  
Novel Approach ◽  
Biophysical Environment

Coral reefs worldwide face unprecedented cumulative anthropogenic effects of interacting local human pressures, global climate change and distal social processes. Reefs are also bound by the natural biophysical environment within which they exist. In this context, a key challenge for effective management is understanding how anthropogenic and biophysical conditions interact to drive distinct coral reef configurations. Here, we use machine learning to conduct explanatory predictions on reef ecosystems defined by both fish and benthic communities. Drawing on the most spatially extensive dataset available across the Hawaiian archipelago—20 anthropogenic and biophysical predictors over 620 survey sites—we model the occurrence of four distinct reef regimes and provide a novel approach to quantify the relative influence of human and environmental variables in shaping reef ecosystems. Our findings highlight the nuances of what underpins different coral reef regimes, the overwhelming importance of biophysical predictors and how a reef's natural setting may either expand or narrow the opportunity space for management interventions. The methods developed through this study can help inform reef practitioners and hold promises for replication across a broad range of ecosystems.

scholarly journals Increased Terrestrial Perturbations Modify Skeletal Properties and Mechanical Strength of Hard Corals

2016 ◽  
Vol 6 (4) ◽  
pp. 153 ◽  
Author(s):  
Shaaban A. Mwachireya ◽  
Tim R. McClanahan ◽  
Isabelle M. Cote ◽  
Brian E. Hartwick
Keyword(s):  
Climate Change ◽  
Coral Reef ◽  
Global Climate Change ◽  
Global Climate ◽  
High Porosity ◽  
Growth Forms ◽  
Management Options ◽  
Skeletal Density ◽  
Change Events ◽  
Hydrodynamic Energy

Skeleton properties determine coral survival by influencing the range of hydraulic conditions colonies can withstand, selection of suitable habitat, ability to compete for space and light, repair damage and the overall fitness and ecological success of scleractinian corals. Skeletal properties of 16 coral species comprising 3 growth forms collected from Kenyan coral reef lagoons were investigated and found to vary considerably not only between species but between reefs as well, with corals exposed to both sediment and nutrients showing consistent lower skeleton density and strength but high porosity compared to those from sediment-unaffected reefs. Further, high skeletal density and strength but low porosity values were measured in branching relative to other growth forms. The present findings also suggest that the negative effects of nutrients on skeleton properties may be counteracted by high hydrodynamic energy, resulting in stronger skeletons in high hydrodynamic energy-nutrient-polluted reef habitats relative to pristine reefs. These findings have important ecological and management implications with regard to the existence, persistence, productivity and protective value of reefs, damage risks, maintenance and conservation of biological diversity with respect to future global climate change events. Consequently, appropriate watershed, reef and fisheries management options the impacts of local anthropogenic stresses (sediments, nutrients, overexploitation) would be expected to alleviate the effects of these disturbances and have the potential to minimize future large-scale coral reef damage resulting from increased and frequent global climate change events, such as increased ocean acidification (due to elevated atmospheric CO2) and sea surface temperature.

ENSO Drove 2500-Year Collapse of Eastern Pacific Coral Reefs

Science ◽  
2012 ◽  
Vol 337 (6090) ◽  
pp. 81-84 ◽  
Author(s):  
Lauren T. Toth ◽  
Richard B. Aronson ◽  
Steven V. Vollmer ◽  
Jennifer W. Hobbs ◽  
Dunia H. Urrego ◽  
...  
Keyword(s):  
Climate Change ◽  
Coral Reef ◽  
Global Climate Change ◽  
Southern Oscillation ◽  
Global Climate ◽  
Intertropical Convergence Zone ◽  
Eastern Pacific ◽  
Convergence Zone ◽  
Reef Growth ◽  
Tropical Eastern Pacific

Cores of coral reef frameworks along an upwelling gradient in Panamá show that reef ecosystems in the tropical eastern Pacific collapsed for 2500 years, representing as much as 40% of their history, beginning about 4000 years ago. The principal cause of this millennial-scale hiatus in reef growth was increased variability of the El Niño–Southern Oscillation (ENSO) and its coupling with the Intertropical Convergence Zone. The hiatus was a Pacific-wide phenomenon with an underlying climatology similar to probable scenarios for the next century. Global climate change is probably driving eastern Pacific reefs toward another regional collapse.

scholarly journals Welcome to the Arbustocene

2005 ◽  
Vol 11 (2) ◽  
pp. 77 ◽  
Author(s):  
Harry F. Recher ◽  
Paul R. Ehrlich
Keyword(s):  
Global Climate Change ◽  
Mass Extinction ◽  
Global Climate ◽  
Chemical Change ◽  
Life Forms ◽  
The Sun ◽  
Evolution Of Life ◽  
Insufficient Time ◽  
Biophysical Environment ◽  
Evolution Of Photosynthesis

The beginning and end of each geological epoch is marked by a major, often cataclysmic, event affecting Earth?s biophysical environment. Most often major periods in Earth?s history requiring a new epoch to be named are remarkable by the mass extinction of dominant life forms and their eventual replacement by new groups of organisms which then dominate Earth?s ecosystems. Only once in pre-history were these spectacular evolutionary events precipitated by a physical or chemical change to Earth?s atmosphere as a result of biological activity. This occurred early in Earth?s history with the release of ?polluting? oxygen after the evolution of photosynthesis. More frequently, punctuations in the evolution of life have been brought on by some virtually instantaneous disruption to climate by extreme volcanic activity or an asteroid strike, such as that which heralded the end of dinosaurs and the dawn of the age of mammals. In these instances, changes to the capacity of Earth?s atmosphere to absorb and reflect light and heat from the Sun initiated a period of rapid global climate change leaving insufficient time for organisms to migrate or adapt.

scholarly journals Leaf Multi-Element Network Reveals the Change of Species Dominance Under Nitrogen Deposition

2021 ◽  
Vol 12 ◽  
Author(s):  
Jiahui Zhang ◽  
Tingting Ren ◽  
Junjie Yang ◽  
Li Xu ◽  
Mingxu Li ◽  
...  
Keyword(s):  
Climate Change ◽  
Global Climate Change ◽  
Global Climate ◽  
N Deposition ◽  
High Plasticity ◽  
Species Dominance ◽  
Novel Approach ◽  
Novel Concept ◽  
Species Specific

Elements are important functional traits reflecting plant response to climate change. Multiple elements work jointly in plant physiology. Although a large number of studies have focused on the variation and allocation of multiple elements in plants, it remains unclear how these elements co-vary to adapt to environmental change. We proposed a novel concept of the multi-element network including the mutual effects between element concentrations to more effectively explore the alterations in response to long-term nitrogen (N) deposition. Leaf multi-element networks were constructed with 18 elements (i.e., six macronutrients, six micronutrients, and six trace elements) in this study. Multi-element networks were species-specific, being effectively discriminated irrespective of N deposition level. Different sensitive elements and interactions to N addition were found in different species, mainly concentrating on N, Ca, Mg, Mn, Li, Sr, Ba, and their related stoichiometry. Interestingly, high plasticity of multi-element network increased or maintained relative aboveground biomass (species dominance) in community under simulated N deposition, which developed the multi-element network hypothesis. In summary, multi-element networks provide a novel approach for exploring the adaptation strategies of plants and to better predict the change of species dominance under altering nutrient availability or environmental stress associated with future global climate change.

Sign in / Sign up

Export Citation Format

Share Document