Download or read book Native and Non native Species Diversity Responses to Fragmentation in Coastal Sage Scrub written by Kristine J. Waldorf and published by . This book was released on 2002 with total page 162 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ecosystems of California written by Harold Mooney and published by Univ of California Press. This book was released on 2016-01-19 with total page 1008 pages. Available in PDF, EPUB and Kindle. Book excerpt: This long-anticipated reference and sourcebook for CaliforniaÕs remarkable ecological abundance provides an integrated assessment of each major ecosystem typeÑits distribution, structure, function, and management. A comprehensive synthesis of our knowledge about this biologically diverse state, Ecosystems of California covers the state from oceans to mountaintops using multiple lenses: past and present, flora and fauna, aquatic and terrestrial, natural and managed. Each chapter evaluates natural processes for a specific ecosystem, describes drivers of change, and discusses how that ecosystem may be altered in the future. This book also explores the drivers of CaliforniaÕs ecological patterns and the history of the stateÕs various ecosystems, outlining how the challenges of climate change and invasive species and opportunities for regulation and stewardship could potentially affect the stateÕs ecosystems. The text explicitly incorporates both human impacts and conservation and restoration efforts and shows how ecosystems support human well-being. Edited by two esteemed ecosystem ecologists and with overviews by leading experts on each ecosystem, this definitive work will be indispensable for natural resource management and conservation professionals as well as for undergraduate or graduate students of CaliforniaÕs environment and curious naturalists.
Download or read book The Effect of Suburban Proximity on Arthropods and Plants in Californian Coastal Sage Scrub written by Shannon M. Kirshtner and published by . This book was released on 2007 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Disturbance and Invasion in Coastal Sage Scrub written by Genie M. Fleming and published by . This book was released on 2005 with total page 186 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Invasive Species Impacts on Coastal Sage Scrub Recovery written by Emily Griffoul and published by . This book was released on 2017 with total page 41 pages. Available in PDF, EPUB and Kindle. Book excerpt: Significant resources are invested in the restoration of degraded Coastal Sage Scrub in Southern California to meet conservation goals. Thus, understanding the resilience of these systems is of great importance given their high value intersection with human settlements. The presence of invasive annual species has been suggested to add complexity to ecological restoration efforts by inhibiting the growth of native species, changing fire regimes, and altering water balance. To further understand these ideas, I utilized a long-term experiment testing the effectiveness of "passive" restoration, the removal of non-native species without expensive site preparation or resource-intensive active planting / seeding of native species, which means that the approach could be designed to have widespread positive effects at potentially minimal costs. I found that passive restoration was successful at meeting restoration goals of increasing native shrub cover. Two ecological mechanisms---the establishment of new individuals on the landscape versus the expansion of plant size of existing shrubs---were likely responsible for the variation in patterns of recovery for localities with different initial native shrub cover. These patterns give insight into how to affect change in communities through management intervention. Better formulating a conceptual model of the contemporary dynamics of Coastal Sage Scrub informs decisions on expending limited resources to different intensities of restoration across a complex landscape to maximally impact conservation.
Download or read book Final Environmental Impact Statement written by and published by . This book was released on 2005 with total page 638 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Restoration of a Coastal Sage Scrub Community Though Invasive Grass Management and Native Species Revegetation written by Alice Esther Levine and published by . This book was released on 2011 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Use of Terrestrial Arthropods to Evaluate Coastal Sage Scrub Restoration written by Wendy Dunbarr and published by . This book was released on 2016 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt: Non-native invasive plants threaten native plants in ecosystems through competition for resources, alteration to ecosystem functions and disturbance regimes, and changes to food webs and mutualistic relationships. Decades of intense disturbance and fragmentation of coastal sage scrub in Southern California have led to type conversion from mixed native shrub cover to non-native annual grassland in many places. Restoration efforts have been carried out by various government and private land managers in an effort to preserve existing coastal sage scrub and create additional habitat. Ecological restoration typically focuses on vegetation for both restoration activities and assessments of project outcomes. Additional measures of ecosystem function should be considered when evaluating the progress of restoration projects. Terrestrial arthropods occupy a wide breadth of niches and provide valuable ecosystem services (seed dispersal, x decomposition, food sources for higher trophic levels). They are also sensitive to subtle, small-scale changes in the environment, which makes them more likely to be restored before larger animals. This study compared terrestrial arthropod assemblages along with vegetation characteristics among three types of sites (invaded, restored, native) to evaluate the success of two coastal sage scrub restoration projects within the Santa Monica Mountains National Recreation Area. Terrestrial arthropod assemblage compositions were successfully restored at both canyons. These results agreed with vegetation results at Cheeseboro Canyon, but contradicted vegetation results at Zuma Canyon. The results of this study indicate that restoration projects at both canyons were successful. The successful restoration of arthropod assemblage compositions despite spatial isolation and vegetative differences of the restored areas supported the Field of Dreams hypothesis that “if you build it, they will come”. The addition of terrestrial arthropod data to the standard practice of vegetation monitoring provided a more thorough evaluation of the status of these restoration projects, and should be used by land managers in the future.
Download or read book Master s Theses Directories written by and published by . This book was released on 2003 with total page 356 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Education, arts and social sciences, natural and technical sciences in the United States and Canada".
Download or read book Ecological Impacts of Nitrogen Deposition Drought and Nonnative Plant Invasion on Coastal Sage Scrub of the Santa Monica Mountains written by Justin Michael Valliere and published by . This book was released on 2016 with total page 201 pages. Available in PDF, EPUB and Kindle. Book excerpt: Multiple drivers of global environmental change increasingly threaten native ecosystems, including atmospheric pollution and resulting changes in climate and nutrient cycling, and the globalization of species. These factors may also have complex and interactive ecological effects. Nitrogen (N) deposition, the input of reactive N from the atmosphere to the earth's surface, is increasing dramatically worldwide due to anthropogenic air pollution, with the potential to negatively impact terrestrial plant diversity. Elevated N deposition may also interact with other drivers of environmental change, for example by promoting the invasion of nonnative plant species, or increasing plant susceptibility to drought or other secondary stressors. Perhaps nowhere in the U.S. is this of more immediate environmental concern than in southern California, which is a global hotspot of biodiversity and one of the most air-polluted and populous parts of the country. High levels of N deposition have been implicated in the widespread conversion of coastal sage scrub (CSS) to annual grasslands dominated by nonnative grasses and forbs. The Santa Monica Mountains National Recreation Area of southern California protects a substantial area of remaining CSS, but due to the park's proximity to the City of Los Angeles, stands of CSS nearest urban areas may be subject to high levels of N deposition. The state of California is also in the midst of a record-breaking drought, beginning in 2011, and this may exacerbate the negative impacts of N deposition and nonnative plant species. The objective of this work is to explore the effects of N deposition, drought and nonnative plant invasion on CSS of the Santa Monica Mountains at multiple ecologically relevant scales. I explored relationships of atmospheric N pollution and N deposition with native plant richness and cover of nonnative species at the landscape level, finding N deposition reduces richness of native herbaceous species and is associated with higher nonnative cover. I also investigated the impact of multiple realistic levels of N addition on CSS in a field fertilization experiment on the low end of the N deposition gradient during a period that coincided with the California drought. Through this experiment, I demonstrated increased N availability may reduce water-use efficiency and drought tolerance of native shrubs, resulting in increased dieback, while concomitantly favoring nonnative annual species. Finally, I explored the role of the soil microbial community in mediating impacts of these factors on native and nonnative plant species, finding that N-impacted soil communities may provide less protection against drought in native shrub seedlings and increase growth of invasive plant species. Collectively, these results illustrate the significant ecological threat of increased N deposition on the severely threatened CSS of southern California, and potential interactions with other drivers of global change such as extreme drought, and nonnative plant invasion.
Download or read book Complex Effects of Habitat Fragmentation on the Quantity and Quality of Pollination Services Within a Coastal Sage Scrub Plant Community written by Adrienne Lee and published by . This book was released on 2016 with total page 39 pages. Available in PDF, EPUB and Kindle. Book excerpt: Habitat fragmentation due to human activity has led to pollinator declines worldwide, yet little is known about how this diversity loss affects pollination services in natural ecosystems. In this study, we investigate the mechanistic links between habitat fragmentation, a proxy for pollinator diversity loss, and the quantity (conspecific pollen deposition) and quality (heterospecific pollen proportion) of pollination services in coastal sage scrub habitats in the San Diego region. We documented pollinator visitation and pollen deposition across ten focal plant species in six natural reserve and six scrub fragment plots. At the level of the community as a whole, habitat fragmentation per se was not a significant driver of conspecific pollen deposition nor was it a significant driver of heterospecific pollen proportion. However, habitat type (reserves vs. fragments) formed statistically significant interactions with other variables in both conspecific and heterospecific proportion models, suggesting that fragmentation can indirectly affect pollination services. The western honeybee, Apis mellifera, was the most numerically dominant floral visitor across all study plots. Due to its high abundance, A. mellifera could influence both conspecific pollen deposition and heterospecific pollen proportion among reserve and fragment plots, potentially altering pollination services within coastal sage scrub habitats. Overall, habitat fragmentation can impart complex effects within plant-pollinator networks, as habitat type was shown to affect plant species differently with regards to changing pollinator variables. These differences in responses from plant species and pollinators could potentially result in a restructuring of plant-pollinator networks.
Download or read book Valuing Chaparral written by Emma C. Underwood and published by Springer. This book was released on 2018-04-09 with total page 483 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chaparral shrubland ecosystems are an iconic feature of the California landscape, and a highly biodiverse yet highly flammable backdrop to some of the fastest growing urban areas in the United States. Chaparral-type ecosystems are a common element of all of the world’s Mediterranean-type climate regions – of which California is one – yet there is little public appreciation of the intrinsic value and the ecosystem services that these landscapes provide. Valuing Chaparral is a compendium of contributions from experts in chaparral ecology and management, with a focus on the human relationship with chaparral ecosystems. Chapters cover a wide variety of subjects, ranging from biodiversity to ecosystem services like water provision, erosion control, carbon sequestration and recreation; from the history of human interactions with chaparral to current education and conservation efforts; and from chaparral restoration and management to scenarios of the future under changing climate, land use, and human population. Valuing Chaparral will be of interest to resource managers, the research community, policy makers, and the public who live and work in the chaparral dominated landscapes of California and other Mediterranean-type climate regions.
Download or read book The Effects of El Ni o and Exotic Plant Invasion on the Two way Interactions Between Small Mammals and Plants in a Southern California Coastal Sage Scrub Food Web written by Jessica Dawn Braswell and published by . This book was released on 2007 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt: Small mammals are among the many taxa in the diverse southern Californian coastal sage scrub and chaparral ecosystems that are threatened by the exotic plant invasions, habitat destruction and fragmentation that have accompanied continued urbanization. Many small mammals not only rely on coastal sage scrub vegetation for shelter but also eat shrub seeds, and therefore depend upon their habitat while also having the ability to shape it. The studies presented here examine the effects of an El Niño-associated heavy rainfall event and invasion by exotic grasses on the small mammal community as well as the role of small mammals in mediating competition between native and exotic plants via selective seed predation. A 4 yr study that included the 1997-1998 El Niño (ENSO) rainfall event investigated changes in density and spatial distribution for 11 rodent species. In the period during and immediately after ENSO, 7 species increased in density and showed range expansions into previously unoccupied areas. The endangered kangaroo rat Dipodomys stephensi declined in abundance and spatial distribution during ENSO. A principle components analysis qualitatively showed changes in small mammal community composition that resulted from differences in relative abundance due to differing magnitudes of species' responses to high precipitation. Most species returned to pre-ENSO population densities and range sizes within 2 yr after El Niño. In addition to the transitory responses to the additional resources available after periods of high precipitation, small mammals also responded to longer-term, perhaps permanent, habitat changes resulting from disturbance-facilitated exotic grass invasions. At higher levels of invasion, abundance of shrub-associated small mammals declined while grass-associated species increased, and overall density of all small mammal species declined. Although no species exhibited a threshold response to invasion, invaded areas supported a depauperate mammal community largely composed of generalist species. Finally, a seed predation study found that rodents preferentially consumed seeds of exotic grasses and forbs over those of native shrubs and grasses. Total mass of seed removed and rates of seed tray visitation varied by season and small mammal density, but a preference for exotic seeds showed that small mammals might slow rates of exotic plant invasion
Download or read book Ecosystems of California written by Harold Mooney and published by Univ of California Press. This book was released on 2016-01-19 with total page 1009 pages. Available in PDF, EPUB and Kindle. Book excerpt: This long-anticipated reference and sourcebook for California’s remarkable ecological abundance provides an integrated assessment of each major ecosystem type—its distribution, structure, function, and management. A comprehensive synthesis of our knowledge about this biologically diverse state, Ecosystems of California covers the state from oceans to mountaintops using multiple lenses: past and present, flora and fauna, aquatic and terrestrial, natural and managed. Each chapter evaluates natural processes for a specific ecosystem, describes drivers of change, and discusses how that ecosystem may be altered in the future. This book also explores the drivers of California’s ecological patterns and the history of the state’s various ecosystems, outlining how the challenges of climate change and invasive species and opportunities for regulation and stewardship could potentially affect the state’s ecosystems. The text explicitly incorporates both human impacts and conservation and restoration efforts and shows how ecosystems support human well-being. Edited by two esteemed ecosystem ecologists and with overviews by leading experts on each ecosystem, this definitive work will be indispensable for natural resource management and conservation professionals as well as for undergraduate or graduate students of California’s environment and curious naturalists.
Download or read book Dynamics of Invasion and Native Species Recovery Following Fire in Coastal Sage Scrub written by Scott Charles Gressard and published by . This book was released on 2012 with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt: Coastal sage scrub (CSS) is an important vegetation type in Southern California, which is under threat from multiple environmental changes such as nitrogen deposition, invasion by exotic species, and accelerating fire regimes. While previous studies have found that CSS can recover pre-fire cover through a successional process, there is concern that high exotic annual grass abundance after fire could prevent native shrub recovery, creating an alternate stable state which requires an active management for restoration of native shrub cover. This study evaluated the performance of focal native and exotic species at early demographic stages (germination, first-year growth and survival) in one recently burned site, and then placed these short-term results in context by examining long-term vegetation dynamics across four CSS sites in San Diego County. Exotic species out-performed native species during all early demographic stages, especially following fire. In the long-term (20 years) cover by native CSS shrubs returned to pre-fire levels at three of the four sites monitored. These results indicate that invasion slows the rate of CSS successional recovery post-fire, and that native CSS vegetation can recover given a long-enough fire return interval. Accelerating fire frequencies, however, may be creating invaded "apparent stable states," because full native shrub recovery does not effectively occur between closely spaced fires.
Download or read book Effects of Moisture Nitrogen and Herbicide Application on the Relationship Between an Invasive Grass and a Rare Coastal Sage Scrub Species Acanthomintha Ilicifolia written by and published by . This book was released on 2017 with total page 91 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nitrogen deposition and precipitation variability can have large effects on the structure and composition of Coastal Sage Scrub communities. These can occur as direct responses to changes in resource availability or indirectly through shifts in the competitive relationships among the many native and non-native plant species. These interactions can influence phenology, limit species distributions, and may play a role in the extinction risk of rare plants. There have been studies on how resources impact invasive species in Coastal Sage Scrub but few have focused on the impacts of invasive grasses on rare, endemic native forbs. I conducted a greenhouse study of the effects of nitrogen and moisture on the relationship between Acanthomintha ilicifolia (a rare native forb) and an invasive grass Brachypodium distachyon. I employed a 3-way factorial design using three moisture levels, three nitrogen treatments, and the application of a selective herbicide used to manage Brachypodium distachyon. Multiple metrics were used to assess the impact of the treatments including aboveground biomass, flower production and timing, leaf size, and chemical composition. For both species, inter and intraspecific competition limited vegetative growth and competitor densities was often more important than the identity of the competitor. We observed weak nitrogen addition effects, likely due to unexpectedly high levels of nitrogen in the natural soil used in the experiment. Total amount of water was not an important factor in this experiment. This could be the result of the relatively mild conditions in the greenhouse or because our experiment could not mimic other stressors like extreme variability in soil moisture and large changes in temperature and insolation. Finally, herbicide treatment was effective at controlling Brachypodium distachyon however significant delays in growth and flowering of Acanthomintha ilicifolia were observed. Herbicide treatment also appeared to alter soil nitrogen relationships. These observed changes in phenology of the endangered species and belowground soil processes need to be considered prior to its continued and wide-spread use in conservation management. Although it can be difficult to extrapolate the results of greenhouse experiments to the field, our results have significant implications for current management practices and warrant further research.
Download or read book Spatial Uncertainty in Ecology written by Carolyn T. Hunsaker and published by Springer Science & Business Media. This book was released on 2013-12-01 with total page 417 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is one of the first books to take an ecological perspective on uncertainty in spatial data. It applies principles and techniques from geography and other disciplines to ecological research, and thus delivers the tools of cartography, cognition, spatial statistics, remote sensing and computer sciences by way of spatial data. After describing the uses of such data in ecological research, the authors discuss how to account for the effects of uncertainty in various methods of analysis.
