Master of Science in Ecological Restoration Applied Research Projects | BCIT Institutional Repository

Master of Science in Ecological Restoration Applied Research Projects

The effect of mowing and hand removal on the regrowth rate of Himalayan blackberry (Rubus armeniacus)
Himalayan blackberry (Rubus armeniacus Focke) is an invasive species in the Pacific Northwest. Mowing and hand removal are two of the common treatments used for controlling Himalayan blackberry. I examined the effectiveness of mowing, hand removal, and control treatments by measuring the mean number of stem and mean stem length during a growing season. Treatments were applied on March 2017. Bi-weekly sampling was from April to August 2017. Data were analyzed with a two-factor split-plot Analysis of Variance (ANOVA) test. The overall trend showed no statistically significant difference between mowing and hand removal treatments in one growing season. Integrated treatments (e.g. mowing + hand removal + planting) are recommended to be used to effectively reduce Himalayan blackberry cover because one removal treatment showed to be insufficient to eliminate Himalayan blackberry., Himalayan blackberry
The effects of canopy closure on precipitation throughfall
Since the 1860s the watershed of Spanish Bank Creek has experienced many ecological disturbances due to extensive old-growth logging and urban development. Most notably, these disturbances have altered the vegetative composition and hydrology throughout the watershed. The historic old-growth forest has been replaced by species typical of earlier seral stages, as well as invasive species such as English ivy (Hedera helix). This disturbed vegetation mosaic is characterized by an arrested ecological trajectory that perpetuates degraded conditions. Urban development has eliminated over a third of the historic length of Spanish Bank Creek and storm drains were installed to direct residential drainage into the stream. The combination of a disturbed forest and degraded hydrology intensifies runoff and associated sediment transport, and decreases the hydraulic retention time of the watershed. This has led to a significant decline in abundance of chum, coho, and cutthroat salmonids in Spanish Bank Creek. Previous research has established how trees partition precipitation into throughfall, stemflow, and interception, however there are few studies examining the effects of canopy closure on throughfall within the context of ecological restoration. Thus, the objective of this paper is to determine if increasing canopy closure can be used as a restoration model to decrease throughfall, and consequently increase the hydraulic retention time of the watershed. Results indicated that greater canopy closure was associated with decreased precipitation throughfall. From these results I formulated a restoration goal and several treatments that would increase canopy closure, and also ameliorate the degraded vegetative composition and hydrology of the watershed. The restoration treatments prescribed in this paper constitute five years of physical enhancements from which self-sustaining biological processes will continue to restore ecosystem function and structure. Successful implementation of these restoration treatments will positively affect regional biota, as well as users of the Pacific Spirit Regional Park who come to recreate, learn, and connect.
Geochemical and biological response of an intertidal ecosystem to localized restoration efforts
Geochemical and biological attributes of three intertidal areas in the Squamish Estuary with different levels of disturbance (low, medium, and high) were assessed to determine short-­term ecosystem responses to localized restoration efforts conducted one year previously on a former log handing site. Sediment and macroinvertebrate variables were analyzed among sites to characterize the ecosystems response and provide insight on the nature and process of an assisted successional trajectory. Invertebrate composition and biomass were lowest on the site with the highest level of disturbance. The high disturbance site also contained the highest percentage of fine sand (0.0067 mm to 0.25 mm). This confirms that in the short term there are distinct site responses to disturbance and ameliorative restoration efforts – even in a highly dynamic estuarine environment. The medium site contained more invertebrates than the low disturbance site indicating that something other than localized disturbance is affecting the invertebrate community on the low site. All sites exhibited a less-­rich and less diverse invertebrate community than that of historical records (circa. 1970-­1980). Invertebrate community in the east delta today is more typical of estuarine environments with higher salinity levels -­ which indicates more widespread levels of disturbance throughout the Estuary is affecting the study sites. This study highlights the importance of considering temporal and spatial scales when setting restoration goals, objectives and creating monitoring plans. Additional monitoring of sediment, invertebrate, and other variables on restored and reference sites is recommended to characterize typical recolonization and reassembly attributes of restoring intertidal estuaries in coastal British Columbia. This would provide evidence and rigor in determining effective restoration techniques and management strategies for a critical and increasingly threatened ecosystem., Macroinvertebrates, Restoration, Sediment, Benthic ecology, Estuaries, Intertidal flats
Restoration of old forest characteristics in a 1957 spacing trial in the Malcolm Knapp Research Forest, British Columbia
Forest managers are interested in determining how stands that have been logged might be managed to restore features characteristic of forests in later-stages of development. Incorporating forest restoration into forest management enables the use of forest-management skills, such as silviculture and regeneration techniques, to manage individual stands for multiple objectives. Therefore, I performed a comparative analysis of large trees, very-large trees, large snags, very-large snags, and large CWD among three stand types (i.e., 60-yr-managed, 140-yr-natural, and 500-yr-natural stands). The 140-yr-natural and 500-yr-natural stands were used as reference conditions to guide the restoration of a 59-yr-managed spacing trial. All attributes differed among stand-types; however, large snags were the most similar attribute between 140-yr-natural and 500-yr-natural stands. Large trees were the fastest attribute to recover in 60-yr-managed stands, however mean values among stand-types still differed. This study highlights the potential of restoring old-natural attributes in younger-managed stands to increase ecological resiliency., forest, natural, managed, prescription, restoration, old-natural attributes
Restoring a culturally eutrophic shallow lake: Case study on Quamichan Lake in North Cowichan, British Columbia
Quamichan Lake is a culturally eutrophic shallow lake located in North Cowichan on Vancouver Island in British Columbia. My research project examined the current trophic status and water quality of Quamichan Lake and investigated a number of watershed and in-lake restoration methods to return the lake back to mesotrophic (nutrient rich) conditions. Based on the data collected, Quamichan Lake is currently in a hypertrophic state caused by excess phosphorus inputs that leads to Cyanophyte phytoplankton species (cyanobacteria) to dominate during the summer. Eutrophication is both an environmental and human health issue as cyanobacteria algal blooms can disrupt the lake ecology and are toxic to most mammals. The goal of my research was to provide the Municipality of North Cowichan and Vancouver Island Health Authority with a comprehensive restoration plan to contribute to the restoration of Quamichan Lake and other lakes in southern Vancouver Island that are experiencing cultural eutrophication., © Kathleen E Moore, 2019. All rights reserved. No part of this work covered by the copyright heron may be reproduced or used in any form or by any means – graphics, electronic, or mechanical including photocopying, taping, or information storage and retrieval systems – without written permission of the author., Eutrophication, Limnology, Watershed Management, Cyanobacteria, Restoration