Author: Kendra Anne KarrPublisher:
ISBN:
Category :
Languages : en
Pages : 406
Book Description
Patterns, Mechanisms and Community Consequences of Variation in Kelp Forest Canopies
Author: Kendra Anne KarrPatterns, Mechanisms, and Consequences of Variation in Brown Algal Dispersal and Recruitment
Author: Daniel Clifford ReedPublisher:
ISBN:
Category : Brown algae
Languages : en
Pages : 258
Book Description
Scale-dependent Patterns of Community Regulation in Giant Kelp Forests
Author: Matthew Sean EdwardsPublisher:
ISBN:
Category : Kelp bed ecology
Languages : en
Pages : 332
Book Description
Degradation, Ecological Restoration and Adaptive Management of Estuarine Wetlands under Intensifying Global Changes, volume II
Author: Tian XiePublisher: Frontiers Media SA
ISBN: 2832551130
Category : Science
Languages : en
Pages : 140
Book Description
Estuarine wetlands play important roles in providing various ecosystem services, such as providing habitat for living organisms, preventing seawater intrusion, conserving biodiversity, regulating microclimate, and promoting nutrient cycling and carbon sequestration. Estuaries are home to many mega-cities, such as New York, San Francisco, Shanghai, and Tokyo, accompanied by frequent human activities. These human-induced disturbances have rapidly altered the structure and function of estuarine ecosystems through land reclamation, pollution, overfishing, and altered flows. Moreover, estuarine wetlands have been greatly threatened by intensifying global climate changes, particularly more frequent tsunamis, sea-level rise, and large-scale biological invasions, which will not only affect primary and secondary productivity, community composition and distribution, and biodiversity, but also natural ecohydrological and biogeochemical processes, and will ultimately disrupt ecosystem services. To mitigate such negative impacts, a growing number of estuarine wetland restoration projects have been undertaken in recent years. These projects aim to re-establish a variety of ecological attributes, including community structure (species diversity and habitat) and ecological processes (energy flow and nutrient cycling), which implies increased resilience and resistance of estuarine ecosystems to abiotic and biotic stressors. However, ecological restoration practices are not always satisfactory in the face of uncertainties from intensifying global changes and socioeconomic variation. Ecologists, biologists, environmentalists have been working on finding more effective solutions to restore degraded estuarine wetland ecosystems on a global scale. The concepts of “nature-based solutions”, “adaptive management” or “ecological networks” seem to offer better prospects and are now being used to reframe estuarine restoration on critical uncertainties reduction, climate change adaptation, and mitigation strategies. As the world enters the United Nations Decade of Ecosystem Restoration (2021–2030), countries and organizations around the world will pay greater attention to the innovation of ecological restoration underpinnings to ensure that estuarine restoration achieves its full potential in delivering social and ecological coordination and, ultimately, sustainable development. Therefore, it is important to discuss how anthropogenic disturbances and climate change affect estuarine wetlands and how the latest restoration framework can guide future practices towards conserving and restoring the biodiversity of estuarine wetlands.
Causes and Consequences of Kelp Forest Foundation Species Loss
Author: Scott Stanley GabaraPublisher:
ISBN:
Category :
Languages : en
Pages : 0
Book Description
With increasing biodiversity loss occurring worldwide, there is a need to understand how these losses will affect ecosystem structure and function. Certain species have a greater impact on the structure and function of ecosystems (i.e. foundation species, keystone species, ecosystem engineers) and therefore their importance suggests a need for understanding their dynamics. I focused on foundation species, which are those that provide the primary habitat and define the communities and ecosystems they create (Dayton 1972, Graham et al. 2007). My dissertation explores different causes and the cascading consequences of kelp forest foundation species loss. In chapter 1, I focus on the consequences of kelp forest biodiversity loss. The loss of the structure and energy that kelps provide leads to changes in species interactions, specifically the trophic complexity of food webs, however how these changes manifest is undescribed (Graham 2004). Sampling the stable isotopes of producer and consumer communities when kelp and other macroalgae are present, versus absent, while comparing these to naturally occurring consumer communities with low biodiversity, has revealed how overall biodiversity loss affects the complexity of food webs. I determined that the reductions in the diversity of kelp forest consumer food resources leads to reductions in the diversity of consumer trophic levels. This comes about through the reduction in food diversity for omnivores and herbivores which propagates to consumers at higher trophic levels. These findings suggest that more intact and biodiverse communities support greater food diversity and trophic complexity. In chapter 2, to better understand kelp physiology and spatial variation, I tested for differences in the stable isotopes and elemental concentrations within and among canopy kelp individuals at islands across the Aleutian Archipelago. Variability was high among islands and led into hypotheses for chapter 3 about potential drivers of this variation in kelp, and ultimately kelp forest communities, across space. In chapter 3, I explored connectivity between terrestrial and marine ecosystems. We understand that connectivity of organic matter, nutrients, and materials can be critical to the structure and function of ecosystems. Interruption of connectivity can occur through top down forcing by invasive upper trophic-level predators. I determined if invasive fox predators have altered connectivity between terrestrial and marine ecosystems using kelp forests at islands that spanned a gradient in invasive fox history, and seabird density, across the Aleutian Island Archipelago. I found evidence that invasive foxes had greater impacts on seabird densities the longer they had been present on islands. The reduction in seabirds has caused less seabird guano-derived nutrients to be available and utilized by kelp forest primary producers, primary consumers, and secondary consumers. This is some of the first evidence that invasive foxes have reduced connectivity between seabirds and kelp forest food webs. Restoring connections between terrestrial and marine ecosystems should be considered in future work and management across the Aleutian Island Archipelago. A consequence of losing kelp forests to urchin grazing is the alteration of competitive interactions. In chapter 4, I tested if higher irradiance and increased intensity of herbivory in areas where urchins have removed kelp forests has altered the tradeoffs between primary producer growth and defense. Across the Aleutian Island chain, the widespread decline in sea otters has resulted in reduced predation on green sea urchins, which has led to dramatic increases in urchin populations, the formation of urchin barrens, and ultimately to overgrazing of much of the region's kelp forests. The differential recovery of kelp forests and the long-term persistence of urchin barrens at certain islands has created a gradient in irradiance and intensity of herbivory that we expect could alter growth and defense in macroalgae. Field and lab results suggested that a common perennial urchin barren macroalga (Codium ritteri) has greater defense than growth within urchin barrens relative to kelp forest individuals. In the laboratory there was little evidence for increased growth under lower light or altered defenses at high light. An experiment testing for spatial variation of urchin grazing rates on C. ritteri revealed that decreasing growth but increasing defense of C. ritteri correlated with higher urchin biomass in the field. Together, these findings suggest that macroalgae occurring within kelp forests may grow faster and be more palatable than macroalgae occurring within urchin barrens. Urchins may be deterred by urchin barren macroalgae causing them to move toward kelp forests where they can more easily consume the less defended macroalgae there, increasing urchin deforestation potential. Together these chapters suggest that the consequences of kelp loss to communities can be (1) through a reduction in community-wide isotopic dietary niche breadth expressed through the loss of omnivore and herbivore dietary niche breadth. (2) Spatial variation in the stable isotopes and elemental concentrations of canopy kelp suggested that differences in nutrient and carbon availability among islands may affect kelp growth and susceptibility to grazing by urchins, ultimately affecting kelp forest persistence. The loss of kelps leads to (3) a reduction in the interaction chain length and propagation of seabird derived nutrients to nearshore marine communities. Lastly, the reduction of kelp and (4) increased intensity of herbivory by urchins within urchin barrens has led to macroalgae with lower growth and increased defenses.
Consequences of Kelp Forest Structure and Dynamics for Epiphytes and Understory Communities
Author: Katherine Kimberlin ArkemaPublisher:
ISBN: 9780549841852
Category :
Languages : en
Pages : 294
Book Description
I investigated the relationship between giant kelp, Macrocystis pyrifera, a large and dynamic structure-forming organism on temperate reefs, and the species that live beneath its canopy and on its surfaces. In particular, my research focused on how the attenuating effect of kelp on light influences the structure and dynamics of the understory community, and how the dampening effect of kelp on currents influences spatial variation in the abundance and demography of a suspension-feeding epiphyte, the colonial and encrusting bryozoan, Membranipora serrilamella.
The Ecology of Giant Kelp Forests in California
Author: Michael S. FosterPublisher:
ISBN:
Category : Giant kelp
Languages : en
Pages : 180
Book Description
Patterns, Mechanisms, and Consequences of Recruitment of a Temperate Marine Reef Fish
Author: Mark Harrison CarrPublisher:
ISBN:
Category : Giant kelp
Languages : en
Pages : 228
Book Description
Global Ecological Consequences of the 1982-83 El Niño-Southern Oscillation
Author: P.W. GlynnPublisher: Elsevier
ISBN: 0080870902
Category : Science
Languages : en
Pages : 587
Book Description
El Niño is a meteorologic/oceanographic phenomenon that occurs sporadically (every few years) at low latitudes. It is felt particularly strongly in the eastern Pacific region, notably from the equator southwards along the coasts of Ecuador and Peru. The El Niño is a component of the ENSO (El Niño Southern Oscillation) which accentuates the intimate and causal connection between atmospheric and marine processes. Obvious manifestations of El Niño in the eastern Pacific are anomalous warming of the sea; reduced upwelling; a marked decline in fisheries, and high rainfall with frequent flooding.The 1982/83 El Niño was exceptionally severe, and was probably the strongest warming of the equatorial Pacific Ocean to occur during this century. The warming was intense and spread over large parts of the Pacific Ocean and penetrated to greater depths than usual. Many eastern Pacific coral reefs that had exhibited uninterrupted growth for several hundred years until 1983 were devasted by the disturbance and are now in an erosional mode. Marine species were adversely affected. The consequent depletion of the plant food base resulted in significant reductions in stocks of fish, squid etc. This led to a mass migration and near-total reproductive failure of marine birds at Christmas Island.Emphasis in this volume is placed on disturbances to benthic communities; littoral populations; terrestrial communities and extratropical regions.
Forest Canopies
Author: Margaret LowmanPublisher: Academic Press
ISBN: 0124575536
Category : Nature
Languages : en
Pages : 543
Book Description
The treetops of the world's forests are where discovery and opportunity abound, however they have been relatively inaccessible until recently. This book represents an authoritative synthesis of data, anecdotes, case studies, observations, and recommendations from researchers and educators who have risked life and limb in their advocacy of the High Frontier. With innovative rope techniques, cranes, walkways, dirigibles, and towers, they finally gained access to the rich biodiversity that lives far above the forest floor and the emerging science of canopy ecology. In this new edition of Forest Canopies, nearly 60 scientists and educators from around the world look at the biodiversity, ecology, evolution, and conservation of forest canopy ecosystems. Comprehensive literature list State-of-the-art results and data sets from current field work Foremost scientists in the field of canopy ecology Expanded collaboration of researchers and international projects User-friendly format with sidebars and case studies Keywords and outlines for each chapter