Archive for the ‘ FUNCTIONAL TRAIT DIVERSITY ’ Category

marginy st. // existing and proposed


Functional Trait Diversity

Functional Trait Diversity (work in progress)

In addition to incorporating natural flows into urban environments, maintaining a biologically diverse structure is essential for healthy urban communities.  Diversity of flora and fauna is important to the long-term resiliency of the ecological system and it has intrinsic social benefits. Sandra Diaz, an ecosystems ecologist, wrote a recent paper on Functional Trait Diversity and the Societal Benefits of Ecosystems that explored the functional traits of organisms and their responses to their environment.  In 2010 at the Conference on Biodiversity + General Assembly, she explained “the concept of functional trait diversity (the kind, range and relative abundance of the functional traits of the organism present in a system) is increasingly used in understanding the links between biodiversity and the various benefits that societies derive from ecosystems”.  (Diaz 2010) As Diaz argues, functional trait diversity is an effective way of connecting biodiversity and ecological services.  It allow for ecosystem services to be understood as an interdependent relationship between humans and nature.

Kristina Hill extends the argument to the disciplines of landscape architecture and urban planning, opining “that from a functional point of view, trait diversity matters to ecosystem performance more than species diversity. It is in our direct interests as humans to conserve and promote trait diversity, in order to increase the ability of the ecosystems around us to provide us with basic services – like cleaning our air and water through biological processes.” (Hill, Managing the Effects of Climate Change 2010)Functional traits are the key way that organisms interact with their environment and their effect on the overall function of ecosystem.   Understanding and quantifying the relationships between social benefits and healthy ecosystem could go a long way to supporting an environmental ethic.

Southern Louisiana // context research

Big Branch Marsh, Louisiana 2011/02

Context Big Branch March Refuge (BBM) comprises over 18,000 acres of managed lands (U.S. Fish and Wildlife) and it is located on the northern shore of Lake Pontchartrain. I went to the BBM refuge because I wanted to experience a hardwood fresh water marsh (pine flatwoods).   The predominate canopy species were the Slash and Longleaf Pines.  The flatwoods lacked an understory. The ground plane consisted of saw grass, cord grass, bulltounge (tubers) and the Louisiana iris.  Many of the species in the wild life refuge are only found in Southern Louisiana.

While I was on the north shore of lake Pontchartrain I saw an American Bittern- a bird only seen every 2 to 5 years.  A rare sighting and it was amazing to watch it sneak back in to the safety of the dense grass.  Is birding in my future?

Synthesis I was seeking an alternative fresh water ecosystem because bald cypress ecosystems are difficult to adapt to an urban context.  Bald cypress is perceived by many residents of New Orleans as a mess species when it is grown in neighborhoods because it is deciduous.  I was struck by the interesting patterns and rhythms created by the Longleaf Pines.  The bark is coarse and intricate.   The trees grow in two formations- thinner smaller trees close together and wider, taller trees spaced farther apart.    The Longleaf pine is an interesting alternative to the bald cypress because it is not deciduous- which means there is no seasonal mess- and it is adapted to live in hydric soil conditions.

Inquiry How would Longleaf pines adapt to urban environment?  Are there any scientific studies analyzing the affect of lead toxin levels on the long-term health of Longleaf pines?  Do any of the grasses help to remove environmental pollutants like lead?

The pictures above are from my commute between New Orleans and the north shore of Lake Pontchartrain.