A relic coral fauna threatened by global changes and human activities, Eastern Brazil

2005 ◽  
Vol 51 (5-7) ◽  
pp. 599-611 ◽  
Author(s):  
Zelinda M.A.N. Leão ◽  
Ruy K.P. Kikuchi
Keyword(s):  
Human Activities ◽  
Global Changes ◽  
Coral Fauna ◽  
Eastern Brazil

scholarly journals Unraveling The Impacts of Meteorological and Anthropogenic Changes on Sediment Fluxes Along an Estuary-Sea Continuum

2021 ◽  
Author(s):  
Florent Grasso ◽  
Eliott Bismuth ◽  
Romaric Verney
Keyword(s):  
Human Activities ◽  
River Flow ◽  
Morphological Changes ◽  
Large River ◽  
Fine Sediment ◽  
Global Changes ◽  
Anthropogenic Pressures ◽  
Estuarine Ecosystem ◽  
Anthropogenic Changes ◽  
Sediment Fluxes

Abstract Sediment fluxes at the estuary-sea interface strongly impact particle matter exchanges between marine and continental sources along the land-sea continuum. However, human activities drive pressures on estuary physical functioning, hence threatening estuarine habitats and their ecosystem services. There is an increasing societal need to better predict the potential trajectories of estuarine sediment fluxes resulting from natural and anthropogenic pressures, but the concomitance of human-induced and meteorological-induced changes makes the responses ambiguous. Therefore, this study explores a 22-year numerical hindcast, experiencing contrasted meteorological conditions and human-induced morphological changes (i.e., estuary deepening and narrowing), in order to disentangle the relative contributions of meteorological and anthropogenic changes on net sediment fluxes between a macrotidal estuary and its adjacent coastal sea. Our results highlight that intense wave events induce fine sediment (≤100 µm) export to the sea but coarser sediment (≥210 µm) import within the estuary. Remarkably, moderate to large river flows support mud import within the estuary. Over 25 years, the reduction of intense wave and river flow events reduces fine sediment export to the sea. In addition, the estuary morphological changes due to human activities increase fine sediment import within the estuary, shifting the estuary from an exporting to importing system. We propose a conceptualization of mud flux response to river flow and wave forcing, as well as anthropogenic pressures. It provides valuable insights into particle transfers along the land-sea continuum, contributing to a better understanding of estuarine ecosystem trajectories under global changes.

scholarly journals Analysis on the Live Coral Cover around Weizhou Island Using MODIS Data

Sensors ◽  
2019 ◽  
Vol 19 (19) ◽  
pp. 4309
Author(s):  
Rongyong Huang ◽  
Huiya Zhang ◽  
Kefu Yu
Keyword(s):  
Coral Reefs ◽  
Human Activities ◽  
Coral Cover ◽  
Empirical Relationship ◽  
Environmental Parameters ◽  
Global Changes ◽  
Live Coral ◽  
Chl A ◽  
Live Coral Cover ◽  
Moderate Resolution Imaging Spectroradiometer

Coral reefs are important as they can help to maintain ecological balance, biological resources, and species diversity on earth. However, they are globally threatened by human activities and climate change. As live coral cover (LCC) is regarded as an important measure of the health of coral reefs, analysis on LCC change associated with environmental parameters, such as chlorophyll-a concentration (Chl-a), sea surface temperature (SST), and photosynthetically active radiation (PAR), is of great value. Research on this front would help us comprehend the changes in coral reefs induced by human activities and global changes. Instead of using spasmodically in-field-measured environmental parameters, in this study, we chose to combine the successive Chl-a, SST, and PAR products of the Moderate Resolution Imaging Spectroradiometer (MODIS) with historic LCC records to establish an empirical relationship using nonlinear optimization. Thereafter, the established relationship was further used to discuss some possible developments of LCCs. According to the experiments, we concluded that the degradation of the LCC around Weizhou Island may be mainly caused by human-activity-caused eutrophication. Besides, we also showed that even if the Chl-a and the PAR can keep constant with current average levels, the corals around Weizhou Island may still be in a risk of disappearing between 2120–2140 as the SST continues to rise.

Plankton and Global Change

2017 ◽  
Author(s):  
Martin Edwards
Keyword(s):  
Global Change ◽  
Human Activities ◽  
Human Populations ◽  
Global Changes ◽  
Nutrient Cycles ◽  
Economic Practices ◽  
Key Concepts ◽  
Plankton Ecology ◽  
Ecological Habitat ◽  
Niche Concept

Global change caused by human activities has had large consequences for the Earth's biosphere through such effects as climate warming, pollution, loss of biodiversity, unsustainable exploitation of resources, loss of habitats, and alterations to nutrient cycles. These changes have accelerated over the last 50 years as human populations have sharply grown, coupled with unsustainable economic practices. The marine pelagic realm, the habitat for planktonic organisms, is the largest ecological habitat on the planet, occupying 71% of the planetary surface. This chapter focuses on the effects of global changes caused by human activities on marine plankton. It introduces some key concepts of plankton ecology such as the ecological niche concept, plankton succession, and the use of planktonic indicators to monitor these changes.

scholarly journals Unraveling the impacts of meteorological and anthropogenic changes on sediment fluxes along an estuary-sea continuum

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Florent Grasso ◽  
Eliott Bismuth ◽  
Romaric Verney
Keyword(s):  
Human Activities ◽  
River Discharge ◽  
Morphological Changes ◽  
Large River ◽  
Fine Sediment ◽  
Global Changes ◽  
Anthropogenic Pressures ◽  
Estuarine Ecosystem ◽  
Anthropogenic Changes ◽  
Sediment Fluxes

AbstractSediment fluxes at the estuary-sea interface strongly impact particle matter exchanges between marine and continental sources along the land-sea continuum. However, human activities drive pressures on estuary physical functioning, hence threatening estuarine habitats and their ecosystem services. This study explores a 22-year numerical hindcast of the macrotidal Seine Estuary (France), experiencing contrasted meteorological conditions and anthropogenic changes (i.e., estuary deepening and narrowing). The hindcast was thoroughly validated for both water column and sediment bed dynamics and showed good capacities to simulate annual sediment budgets observed from 1990 to 2015. We aim at disentangling the relative contributions of meteorological and human-induced morphological changes on net sediment fluxes between the estuary and its adjacent coastal sea. Our results highlight that intense wave events induce fine sediment (≤ 100 µm) export to the sea but coarser sediment (≥ 210 µm) import within the estuary. Although intense river discharges induce mud export to the sea, moderate to large river discharges prove to support mud import within the estuary. Wave and river discharge events were less intense in 2005–2015 than in 1990–2000, reducing fine sediment export to the sea. The estuary deepening and narrowing due to human activities increased fine sediment import within the estuary, shifting the estuary from an exporting to importing system. We propose a conceptualization of mud flux response to river discharge and wave forcing, as well as anthropogenic pressures. It provides valuable insights into particle transfers along the land-sea continuum, contributing to a better understanding of estuarine ecosystem trajectories under global changes.

scholarly journals Mitrapsylla rupestris sp. nov., a psyllid (Hemiptera, Psylloidea) associated with Poiretia bahiana (Fabaceae) endemic to the Espinhaço mountain range (Brazil, Bahía)

2021 ◽  
Vol 5 ◽  
pp. 69-75
Author(s):  
Daniel Burckhardt ◽  
Dalva L. Queiroz
Keyword(s):  
New Species ◽  
Species Diversity ◽  
Host Plant ◽  
Human Activities ◽  
Conservation Strategies ◽  
Mountain Range ◽  
Espinhaço Range ◽  
Eastern Brazil ◽  
High Species Diversity

Mitrapsylla rupestrissp. nov., associated with Poiretia bahiana C. Mueller (Fabaceae, Faboideae, Dalbergieae), is described, diagnosed and illustrated. The new species is morphologically similar to M. aeschynomenis, M. aurantia, M. cubana and M. didyma from which it differs in details of the terminalia and the host plant. Poiretia constitutes a previously unknown psyllid host. As its host, Mitrapsylla rupestrissp. nov. is probably endemic to rock habitats of the Espinhaço Range in eastern Brazil. These rock habitats display a high species diversity but are seriously threatened by human activities. More research on these habitats is urgently needed to design efficient conservation strategies.

Mortality of the Antillean manatee, Trichechus manatus manatus, in Ceará State, north-eastern Brazil

2008 ◽  
Vol 88 (6) ◽  
pp. 1133-1137 ◽  
Author(s):  
Ana Carolina Oliveira de Meirelles
Keyword(s):  
Spatial Distribution ◽  
Human Activities ◽  
East Coast ◽  
Seasonal Distribution ◽  
Fishing Gear ◽  
Trichechus Manatus ◽  
Direct Capture ◽  
Gill Nets ◽  
Eastern Brazil ◽  
North Eastern

Manatee mortality in Ceará State (north-eastern Brazil) is analysed from twenty-five strandings between 1987 and 2002. The majority of the causes were related to the ‘dependent calf’ category (83.3%). Direct human-related causes were attributed to incidental catches in fishing gear (shrimp trawling and gill-nets) (12.5%) and direct capture (4.2%). Spatial distribution was not uniform, with the highest number of strandings on the east coast. The number of strandings has increased since 1999, and the seasonal distribution showed peaks in February, March and January, in that order. The stranding of manatee calves in Ceará State seems to be indirectly related to human activities that impact coastal nursing habitats.

scholarly journals Global change effects on plant communities are magnified by time and the number of global change factors imposed

2019 ◽  
Vol 116 (36) ◽  
pp. 17867-17873 ◽  
Author(s):  
Kimberly J. Komatsu ◽  
Meghan L. Avolio ◽  
Nathan P. Lemoine ◽  
Forest Isbell ◽  
Emily Grman ◽  
...  
Keyword(s):  
Community Structure ◽  
Global Change ◽  
Community Composition ◽  
Plant Community ◽  
Plant Communities ◽  
Human Activities ◽  
Global Changes ◽  
Herbaceous Plant ◽  
Community Responses ◽  
Similar Frequency

Global change drivers (GCDs) are expected to alter community structure and consequently, the services that ecosystems provide. Yet, few experimental investigations have examined effects of GCDs on plant community structure across multiple ecosystem types, and those that do exist present conflicting patterns. In an unprecedented global synthesis of over 100 experiments that manipulated factors linked to GCDs, we show that herbaceous plant community responses depend on experimental manipulation length and number of factors manipulated. We found that plant communities are fairly resistant to experimentally manipulated GCDs in the short term (<10 y). In contrast, long-term (≥10 y) experiments show increasing community divergence of treatments from control conditions. Surprisingly, these community responses occurred with similar frequency across the GCD types manipulated in our database. However, community responses were more common when 3 or more GCDs were simultaneously manipulated, suggesting the emergence of additive or synergistic effects of multiple drivers, particularly over long time periods. In half of the cases, GCD manipulations caused a difference in community composition without a corresponding species richness difference, indicating that species reordering or replacement is an important mechanism of community responses to GCDs and should be given greater consideration when examining consequences of GCDs for the biodiversity–ecosystem function relationship. Human activities are currently driving unparalleled global changes worldwide. Our analyses provide the most comprehensive evidence to date that these human activities may have widespread impacts on plant community composition globally, which will increase in frequency over time and be greater in areas where communities face multiple GCDs simultaneously.

6. Projection

2016 ◽  
pp. 91-106
Author(s):  
Tim Lenton
Keyword(s):  
Climate Change ◽  
Human Activities ◽  
Global Changes ◽  
Earth System ◽  
System Models ◽  
The Earth ◽  
The Future ◽  
Earth System Models ◽  
Specific Challenge

Where is the Earth system heading in the Anthropocene? To even begin to answer this question requires a model of how the Earth system works, and the answer depends on our collective activities as a species, and how the Earth system responds to those. The model’s role is to forecast the consequences of different assumptions about future human activities. ‘Projection’ introduces ‘Earth system models’ and some of the crucial assumptions that go into using them to forecast the future. It outlines their projections, going from shorter to longer timescales, and from the specific challenge of projecting climate change to the broader challenge of exploring other global changes.

Roads Accelerate the Invasion Process of Alien Species

2011 ◽  
Vol 347-353 ◽  
pp. 1483-1487
Author(s):  
Hua Chen ◽  
Jian Liu ◽  
Tong Xue ◽  
Ren Qing Wang
Keyword(s):  
Alien Species ◽  
Human Activities ◽  
Native Species ◽  
Economic Loss ◽  
Global Changes ◽  
Invasion Process ◽  
Long Distance Dispersal ◽  
Long Distance ◽  
Human Disturbances ◽  
Considerable Economic Loss

Biological invasions have been identified as one of the human-induced global changes, which not only threaten native biodiversity but also cause a considerable economic loss both globally and locally. The long distance dispersal of alien species is often facilitated by human activities and disturbances. This paper summarized lots of paper to explain how road affect the local biodiversity and accelerate the invasion process of alien species. We discuss several aspects to clarify this issue: the impacts of roads affect the alien and native species in new regions, environmental conditions near roads affect the effect of roads, the effects of roads on alien species in high altitude regions, the effects of roads on different propagation manner of alien species and at last the fast growth of road length and alien species in China. Human disturbances promote the performance and abundance of alien species in new regions, and roads as one key of human disturbances act as corridors for the flow of alien propagules and seeds into new landscapes and ultimately accelerate the invasion process of alien species.

Global Changes in Children's Lives

2018 ◽  
Author(s):  
Uwe P. Gielen ◽  
Sunghun Kim
Keyword(s):  
Global Changes
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