Ecosystem approach to management

I. What is Ecosystem Management?A. The ecosystem

B. Past Resource Management Approach

C. New ecosystem management approach

D. Examples

II. Using Natural Processes under Ecosystem Management

A. Disturbance

B. Succession

C. Important types of natural disturbance

Epic of Gilgamesh – ancient Mesopotamia

Social systems developed by the civilization far outstretched the constraints of ecological systems

I. What is Ecosystem Management?

A. The Ecosystem = All the organisms in a given area interacting with the physical environment so that a flow of energy leads to trophic structure, biotic diversity and material cycles.

“Any land management system that seeks to protect populations of all native species, perpetuates natural disturbance…at the regional scale, adopts a planning time line of centuries, and allows human use at levels that do not result in long-term ecological degradation.”

Components of the ecosystem1) Energy flow – thermal

energy, primary production, secondary production

2) Nutrient flow – organic detritus (detritovores extract soluble substances)

3) Abiotic – latitude/longitude, temp., moisture, wind, exposure, elevation, geology, geography, water current, salinity, amount of oxygen

4) Biotic – species in the community

B. Past Resource Management Approach

→Multiple use – Pinchot’s resource conservation ethic• Resource Management -Wildlife managers/ fisheries/

forestry– Manipulate processes of ecosystems to boost desired

species’ populations– Treat populations as commodities within ecosystems– Separate Agencies manage separate populations– Federal land use – value part of the ecosystem as a

resource– Management UNIT =

C. New Ecosystem Management Approach

• Recognizes the interrelated nature of air, land, water and all living beings rather than geopolitical boundaries and departmental divisions.

• Calls for creative partnerships that look at natural boundaries, such as watersheds, as the unit of management.

• It was endorsed at the fifth Conference of the Parties to the Convention on Biological Diversity (CoP 5 in Nairobi, Kenya; May 2000) as the primary framework for action under the Convention.

An ecosystem approach involves the following principles:

Includes the whole system, and not just parts of it Based on a broad spatial and temporal scaleFocuses on interrelationships among the components of

the environment and between living and non-living things Includes consideration of the natural environment,

society and economy & emphasizes collaborative decision making

Is based on natural geographic units (defined by ecological boundaries) such as watersheds

Ecosystem management = Holistic approach

Considers humans and all living components as one interacting system

Seeks sustainable human useEmphasizes interaction between

stakeholders Land owners: private individuals, industry,

county/state, tribal lands, federal lands,

• Sustainable management at an ecosystem level will only succeed when human welfare & economic considerations are taken into account

Each unit is represented by an ecosystem team which has developed its own biologically- based strategy. The Service has identified and defined boundaries

for 53 ecosystem units by grouping the USGS defined watersheds -

D. Examples

1) Northwest Forest Plan (NWFP)

• http://www.fs.fed.us/r5/nwfp/

1) Connectivity

2) Landscape heterogeneity

3) Structural complexity

4) Integrity of aquatic systems

• Plan represents an agreement among diverse stakeholders to manage across wide forest and insitutional boundaries

2) Greater Yellowstone Ecosystem

Number of various agencies governing the management of the lands

• 2 national parks: Yellowstone and Grand Teton (parts of Wyoming, Montana & Idaho)

• 3 national wildlife refuges

• Headwaters of 3 major river systems: Yellowstone, Snake and Green Rivers

3) Bocas del Toro, Panama

• http://www.iucn.org/themes/cem/ourwork/projects/panama.html

II. Using Natural Processes under Ecosystem Management:

• Management must protect ecological processes that determine the characteristics of the ecosystem

Ecological Processes:

A. Disturbance

B. Succession

C. Important types of natural disturbance

A. Natural Disturbance

• A force that alters a community and usually removes organisms from it, but is an integral part of ecosystem structure/function– Intermediate level: positive effects (increase

heterogeneity) reduces competition, increases biodiversity

•There is an impact of established species upon their environments…causes changes in environmental conditions.

time

environmentalconditions

optimalfor species#1

optimalfor species#2

optimalfor species#3

N

B. Succession

Primary community: arises in a lifeless areaSecondary community: occurs after disturbance

Secondary forest

Mature forest – nearing climax

1) Fire as a natural disturbance

Habitat heterogeneity, amount of edgeSpecies DiversityNutrient uptakeNutrient loss from soilErosion and surface runoffStream flow ratesGrazing and browsing of ungulatesEstablishment of early successional species

Prescribed Burns -the controlled application of fire to existing naturally occurring fuels under specified environmental conditions, which allows the fire to be confined to a predetermined area.

• suppressed fires can result in overgrowth of non-native shrubs, trees and grasses

• Native, fire-resistant species survive –some even dependant upon fire

• Leaf litter & undergrowth removed -helps to remove the “fuel” for future fires

• Problem: potential to spread to inhabited areas – out of control…

http://flame.fl-dof.com/Gifs/Env/anat.jpg

Prairie ecosystem:In a study comparing an area burned in April after the snows melt to an area unburned for 25 years, there was a three to fourfold increase in forbs (flowers) for 1 to 2 growing seasons.

Effects of Flooding• Natural flooding –

increases habitat heterogeneity

Damn Dams!

Effects of Dams on ecosystems

3). Herbivores – small scale disturbance agents

• Regulate habitat, energy flow, nutrient cycling, plant nutrition

• prevent vertical development, reduce litter and soil nutrients

4. Predation

Related concept: Intermediate disturbance hypothesis

PredationLow High

Num

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of S

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Experiment 1: Artificial ponds

• Cattle tanks

• Stock with leaf litter, plants, invertebrates

• 1200 newly hatched larvae of a mix of the 6 anuran species (150 to 300 each species)

• Predators: 0, 2, 4, 8 adult newts

Temporary pond amphibians

• Predators … salamanders– Newts

(Notophthalmus) • adults and larvae

• Prey: anuran larvae

Effect of newt predation• 0 newts

– Scaphiopus dominates, Hyla rare

• 2 newts – Scaphiopus dominates, Hyla crucifer

increases– Maximal mass of anuran adults; Maximal

evenness

• 4 newts – Hyla crucifer & Scaphiopus equally abundant

• 8 newts– 60% Hyla crucifer, all others rare