BEN
BOTANICAL ELECTRONIC NEWS
ISSN 1188-603X

No. 465 March 21, 2013 aceska@telus.net Victoria, B.C.
Dr. A. Ceska, P.O. Box 8546, Victoria, B.C. Canada V8W 3S2

BOTANY WASHINGTON 2013 - SPRING DIVERSITY IN THE LOWER GRAND COULEE

BotWA 2013 (as Art Kruckeberg calls it) will be held May 31 - June 2nd and hosted at Sun Lakes State Park, Coulee City, WA. The link to the event Web page is here: http://www.wnps.org/botany_wa/index.html

WASHINGTON NATIVE PLANT SOCIETY - GRASS IDENTIFICATION WORKSHOP - JUNE 12-14, 2013

The Washington Native Plant Society and the University of Washington Herbarium at the Burke Museum are co-sponsoring "Know Your Grasses: Identification and Appreciation of Grass".
Dates: 9:00 am Wednesday, June 12 to 1:00 pm Friday, June 14, 2013 Instructor: Clayton Antieau, M.S., Ph.C. Location: Room 246, Hitchcock Hall, University of Washington, Seattle, Washington Additional information and registration details can be found here: http://www.wnps.org/grass-workshop/index.html

BOTANY ALBERTA 2013 - LAKE LOUISE, ALBERTA - AUGUST 3-5, 2013

BOTANY ALBERTA is planning their annual get-together for the weekend before BOTANY BC: August 3-5 in Lake Louise, AB. For costs and more information about this event check the Alberta Native Plant Council website http://www.anpc.ab.ca/ or contact Mari Decker at m_decker@telus.net . Accommodations for the Alberta meeting will be at the beautiful and reasonably priced Lake Louise Hostel and the Lake Louise campground for those who prefer to tent. Bonus Botanizing: There is also an opportunity to extend your trip by attending BOTANY BC 2013 and enjoying two botany weekends in a row!

BOTANY BC 2013 - REVELSTOKE/GOLDEN - AUGUST 8-11, 2013

This year Botany BC will be held in the spectacular Columbia Mountains near Revelstoke from the evening of Thursday August 8th through to Sunday August 11th: http://members.shaw.ca/botanybc/

Our main headquarters for Botany BC 2013 will be in the hall at the charming and centrally located Revelstoke Senior's Centre, 603 Connaught Ave. Revelstoke.

Both BOTANY ALBERTA and BOTANY BC will offer a number of hikes, including sightings of whitebark pine, limber pine, numerous other rare plants, bryophytes and lichens, and of course. incredible mountain views.

PUTTING OUR FAITH IN BIODIVERSITY TO THE TEST

From: Tim Ennis, Director of Land Stewardship, Nature Conservancy Canada, Tim.Ennis@natureconservancy.ca

The idea that a balanced and diverse investment portfolio is important to preserve capital investments, promote growth and mitigate the risks of financial losses in a volatile economy has long been promoted as the best strategy towards financial health. A recent study published this week in Nature brings scientific validation to the long-held belief of ecologists that the nature works in this same way. Ecosystems are better able to recover from disturbances when biological diversity is high. Nature doesn't put all of its eggs in one basket either.

The 10-year study, conducted by researchers at the Department of Integrative Biology at the University of Guelph and the UBC Center of Biodiversity Research under the leadership of Dr. Andrew MacDougall tested the theory that even apparently healthy and productive natural areas around the world are vulnerable to sudden and catastrophic collapse if they lack the very thing that enables stability when adapting to rapid change: diversity (MacDouglal, A. & al. 2013 - see the Abstract below).

As a conservationist and a scientist, I am gratified to see hard scientific evidence that supports the basic mission of nature conservation organizations and partnerships around the world: to protect, restore and enhance biodiversity. MacDougall conducted his study on the Cowichan Garry Oak Preserve on Vancouver Island, a property owned by the Nature Conservancy of Canada (NCC). The Preserve is a rare remnant of Garry oak savannah that once was much more common in the Pacific Northwest. Today only about 5% of this habitat remains. The rest has been converted to agricultural, residential and urban land uses. Many of the plants and animals that once thrived in the Garry oak ecosystems are at risk of extinction. Some have already disappeared.

When NCC bought the Preserve in 2000, it was far from pristine. The bones of the old native ecosystem were there, but many of the open meadows were overrun with non-native, invasive plants like Scotch broom (Cytisus scoparius), Common Hawthorn (Crataegus monogyna), and Himalayan blackberry Rubus armeniacus). Using every conceivable technique from cutting, weeding and mowing the invaders to replanting and seeding native species to conducting prescribed burns we are slowly restoring the original habitat and, in so doing, enhancing native biodiversity in the area.

The partnership with Dr. MacDougall provides him with a real-life testing ground for his research while also fulfilling NCC's management goals for the Preserve. I have witnessed first hand the way the land has responded to fire, one of the key methods Dr. MacDougall used to disturb the ecosystem in order to test its resilience. In the areas of the Preserve where we have restored the Garry oak meadows, complete with native grasses and wildflowers, fire was like the equivalent of a tall drink of water. The spring wildflower bloom that followed was a spectacular display of myriad colours, textures and sounds with thousands of native bees and butterflies literally vibrating the ground we stood on.

In places on the Preserve where restoration had not yet taken place and the meadows had long ago been converted to healthy and productive hayfields fields with only a single species of agricultural grass, MacDougall's fire was devastating. Within one growing season, invasive shrubs had completely taken over. The hayfield was even further away from functioning as a native ecosystem, and was no longer any good for agriculture either.

PERSISTENT HUMAN DISTURBANCE INCREASES VULNERABILITY TO ECOSYSTEM COLLAPSE

From: MacDougall, A.S., K. S. McCann, G. Gellner & R. Turkington. 2013. Letter: Diversity loss with persistent human disturbance increases vulnerability to ecosystem collapse Nature 494, 86-89 (06 February 2013) | doi:10.1038/nature11869

Link to paper: MacDougall et al.

ABSTRACT

Long-term and persistent human disturbances have simultaneously altered the stability and diversity of ecological systems, with disturbances directly reducing functional attributes such as invasion resistance, while eliminating the buffering effects of high species diversity. Theory predicts that this combination of environmental change and diversity loss increases the risk of abrupt and potentially irreversible ecosystem collapse, but long-term empirical evidence from natural systems is lacking. Here we demonstrate this relationship in a degraded but species-rich pyrogenic grassland in which the combined effects of fire suppression, invasion and trophic collapse have created a species-poor grassland that is highly productive, resilient to yearly climatic fluctuations, and resistant to invasion, but vulnerable to rapid collapse after the re-introduction of fire. We initially show how human disturbance has created a negative relationship between diversity and function, contrary to theoretical predictions. Fire prevention since the mid-nineteenth century is associated with the loss of plant species but it has stabilized high-yield annual production and invasion resistance, comparable to a managed high-yield low-diversity agricultural system. In managing for fire suppression, however, a hidden vulnerability to sudden environmental change emerges that is explained by the elimination of the buffering effects of high species diversity. With the re-introduction of fire, grasslands only persist in areas with remnant concentrations of native species, in which a range of rare and mostly functionally redundant plants proliferate after burning and prevent extensive invasion including a rapid conversion towards woodland. This research shows how biodiversity can be crucial for ecosystem stability despite appearing functionally insignificant beforehand, a relationship probably applicable to many ecosystems given the globally prevalent combination of intensive long-term land management and species loss.

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