Author: Dean Francis AntonioPublisher:
ISBN:
Category : Asterina
Languages : en
Pages : 90
Book Description
Factors Influencing the Survival of Giant Kelp, Macrocystis Pyrifera, Gametophytes in Stillwater Cove, Carmel Bay, California and the Algal Food Preference of the Bat Star, Asterina Miniata, in the Laboratory
Author: Dean Francis AntonioPublisher:
ISBN:
Category : Asterina
Languages : en
Pages : 90
Book Description
The Roles of Life Stage and Climate Change on the Persistence of Juvenile Giant Kelp, Macrocystis Pyrifera, Under Herbivory
Author: Crystal NgPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Giant kelp forests are some of the most productive and biodiverse ecosystems in the world, but they are vulnerable to stressors associated with global climate change. As a foundation species, giant kelp (Macrocystis pyrifera) provides habitat, food, and refuge for hundreds of species, many of which are economically important. Much of what is known about giant kelp is focused on the adult stage and the abiotic factors influencing the persistence and recovery of this species. However, under increasing environmental variability, it is critical to understand the factors impacting the survival of juvenile kelp, which has direct implications for the success of the adults. One of the largest gaps in our knowledge of giant kelp forests is the role of a diversity of grazers on the early life stages of M. pyrifera, and virtually nothing is known about the impacts of climate change on these species interactions. In this dissertation, I use both laboratory and field experiments to quantify the impacts of four grazers on two life stages of juvenile kelp under ocean acidification and hypoxia. I found that grazers are a significant source of mortality on juvenile kelp, and that an often overlooked herbivore in the literature, the brown turban snail, emerges as a dominant grazer on both microscopic and macroscopic stages. Under climate change, consumption is significantly reduced, increasing estimated kelp survival, and hypoxia drives these decreases in consumption across all four grazing species. By utilizing natural variability regimes within an upwelling season, I found through field experiments that grazing rates decreased with high monthly oxygen variance, suggesting that cumulative impacts of more extreme conditions may also impact herbivore feeding behavior. Overall, the results of this dissertation demonstrate that herbivory can play a significant role influencing the persistence of giant kelp, and that under the threat of climate change, these species interactions will be significantly weakened, which has implications for kelp forest ecosystems and the transfer of primary productivity through these diverse food webs. This dissertation provides critical information on the ecology and persistence of giant kelp forests and gives us a greater understanding of climate change impacts on marine communities.
The Effects of Harvesting Macrocystis Pyrifera on Understory Algae in Carmel Bay, California
Author: Robert Scott KimuraPublisher:
ISBN:
Category : Giant kelp
Languages : en
Pages : 252
Book Description
Micronutrient Requirements for Macrocystis Pyrifera (L.) C. A. Agardh (giant Kelp) Gametophytes Determined by Means of a Chemically Defined Medium, Aquil
Author: James S. KuwabaraPublisher:
ISBN:
Category : Giant kelp
Languages : en
Pages : 202
Book Description
The Ecology of Giant Kelp Forests in California
Author: Michael S. FosterPublisher:
ISBN:
Category : Giant kelp
Languages : en
Pages : 180
Book Description
Return of the Mac: how Density Affects the Survival of Juvenile Giant Kelp (Macrocystis Pyrifera) in Point Loma Kelp Forest, San Diego, CA
Author: Publisher:
ISBN:
Category : Electronic books
Languages : en
Pages : 34
Book Description
Adult giant kelp, Macrocystis pyrifera, release billions of zoospores into the surrounding kelp forest community during each reproductive season. The young sporophytes that ultimately develop from these zoospores undergo a process of self-thinning until their densities are reduced to levels that can be sustained by environmental conditions at that time. We examined the effects of recruitment density on the survival of juvenile M. pyrifera within naturally occurring patches in the Point Loma kelp forest, San Diego, CA and found that the total density of all macroalgae within the patch had no effect on M. pyrifera survival. Instead, we found that density-dependent mortality within each patch was driven almost entirely by the density of conspecifics. This pattern, and the direct effects of recruitment density on juvenile M. pyrifera survival was further tested experimentally by oputplanting two size classes of juvenile M. pyrifera (medium size class, 5-25cm in height; large size class, ~1m in height) at three densities (20, 60 and 120 individuals m-2, and 2, 4 and 8 individuals m-2 for medium and large size classes, respectively). While the large size class exhibited the overall greatest survival, declines in survival were consistent through time for all density treatments and for each size class, with the surviving sporophytes converging on similar densities (8 m- 2 ±4 for the medium size class, and 1 m-2 ±1 for the large size class). Together, our observational and our experimental studies demonstrate that, regardless of the initial density at which M. pyrifera recruits, the resulting patches of juvenile sporophytes will thin to similar densities that are presumably appropriate for their survival under the existing environmental conditions. This self-thinning process is an example of density-dependent mortality that operates in addition to other stressors such as grazing, sand scour, entanglement and dislodgement due to wave energy, each of which effectively reduces the population size of new M. pyrifera recruits to a level that is sustainable by the kelp forest community.
The Effects of the Operation of the San Onofre Nuclear Generating Station on the Giant Kelp, Macrocystis Pyrifera
Author: Aspects of Community Organization in a Temperate Kelp Forest Habitat
Author: James Minoru WatanabePublisher:
ISBN:
Category :
Languages : en
Pages : 486
Book Description
The Effects of Discharges from the San Onofre Nuclear Generating Station on the Giant Kelp, Macrocystis Pyrifera: Background information and the biology of kelp
Author: Thomas A. DeanPublisher:
ISBN:
Category : Giant kelp
Languages : en
Pages : 564
Book Description
Seasonal Patterns in the Productivity of a Giant Kelp (Macrocystis Pyrifera) Forest
Author: Richard Carl ZimmermanPublisher:
ISBN:
Category : Algae
Languages : en
Pages : 408
Book Description