The Effects of Ecological Restoration on a Coastal Sage Scrub Site in Central California Under Invasion by Carpobrotus Edulis PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download The Effects of Ecological Restoration on a Coastal Sage Scrub Site in Central California Under Invasion by Carpobrotus Edulis PDF full book. Access full book title The Effects of Ecological Restoration on a Coastal Sage Scrub Site in Central California Under Invasion by Carpobrotus Edulis by Celeste Wilson. Download full books in PDF and EPUB format.
Author: Celeste Wilson Publisher: ISBN: Category : Ice plant Languages : en Pages : 284
Book Description
The results of this study demostrated that, if Carpobrotus edulis is exterminated, indigenous species, specifically Baccharis pilularis, will replace it under certain environmental conditions.
Author: Celeste Wilson Publisher: ISBN: Category : Ice plant Languages : en Pages : 284
Book Description
The results of this study demostrated that, if Carpobrotus edulis is exterminated, indigenous species, specifically Baccharis pilularis, will replace it under certain environmental conditions.
Author: Claire Elizabeth Wainwright Publisher: ISBN: 9781124540108 Category : Languages : en Pages : 31
Book Description
Exotic annual grasses are invading native plant communities in many areas including the western United States, and pose a significant challenge to habitat restoration. Observations in California grasslands suggest that exotic species may become active earlier in the growing season than native species, and that this distinct phenology may contribute to invasion success. We hypothesized that flexible germination cues may allow exotic annual grasses to start annual growth early each growing season and preempt resources prior to native seedling establishment, a kind of seasonal priority effect. Flexible germination cues could incur a cost, however, if they cause seeds to germinate before the onset of favorable growing conditions. To evaluate these predictions, we compared native and exotic species performance in a coastal sage scrub community under both early (off-season) and ambient (natural) rainfall timings. Exotic annual grasses germinated substantially with off-season watering, but none of the early seedlings survived until the onset of the natural rains. Exotic annual grasses that experienced off-season watering had a depleted seedbank and lower germination following the natural rains. In contrast, native species did not germinate following the off-season watering pulse, and instead emerged with the beginning of the cold natural rains. Our results suggest that phenology is an important factor influencing invasion success and invader impact. Under some conditions, pre-growing season watering could be an important restoration strategy for native plant communities in early stages of invasion by depleting the exotic seedbank and allowing for native species to establish with reduced competition.
Author: Emily Griffoul Publisher: ISBN: 9780355414226 Category : Languages : en Pages : 41
Book Description
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.
Author: Wendy Dunbarr Publisher: ISBN: Category : Languages : en Pages : 66
Book Description
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.
Author: Justin Michael Valliere Publisher: ISBN: 9781369092448 Category : Artemisia Languages : en Pages : 201
Book Description
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.
Author: Scott Charles Gressard Publisher: ISBN: 9781267904287 Category : Languages : en Pages : 27
Book Description
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.
Author: Celeste Wilson
Author: Celeste Wilson
Author: Claire Elizabeth Wainwright
Author: Emily Griffoul
Author: 
Author: Wendy Dunbarr
Author: Justin Michael Valliere
Author: Scott Charles Gressard
Author: Alice Esther Levine
Author: Tara Elizabeth Stark
Author: Matt V. Talluto