Managing Ecosystems to improve resilience (UNDP presentation)

Annual meeting of Biodiversity Projects, Bratislava 12 – 14 October 2010.

Adriana Dinu, Regional Practice Leader Environment and Energy

October 12th, 2010

© 2010 UNDP. All Rights Reserved Worldwide.

Proprietary and Confidential. Not For Distribution Without Prior Written Permission.

MANAGING ECOSYSTEMS TO IMPROVE

RESILIENCE

Putoransky, Taimyr


Overview

What is Ecosystem Resilience?

- Definitions

Why is Resilience important?

- Key drivers of biodiversity loss

- Tipping points

- Loss of Resilience could lead to collapse

Managing for ecosystem resilience

- Landscape planning

- Grasslands

- Forests

Nalichevo Park, Kamchatka


What is Resilience?

Materials science: property of returning to the original shape after deformation

that does not exceed the elastic limit

Psychology: the positive capacity of people to cope with stress and catastrophe

Ecology: capacity of an ecosystem to persist in the face of disturbance

• cope with disturbances (storms, fire) without shifting into a qualitatively

different state

• withstand external pressures and reorganize, so as to still retain the same

function, structure, identity and feed-backs

A resilient ecosystem is able to maintain its ‘identity’ in terms of taxonomic

composition, structure, ecological functions, and process rates


Without resilience, ecosystems become vulnerable to the effects of

disturbance that previously could be absorbed

Climate change, interacting with other land use pressures, might

overcome the resilience of even some large areas of primary ecosystems,

pushing them into a permanently changed state.

Past an ecological ‘tipping point’, ecosystems could be transformed into

a different type, and, in extreme cases, a new ecosystem state.

The new state may be biologically and

economically impoverished, and irreversible.

Why is Resilience Important?


Drivers of biodiversity loss


Changes in ecosystem structure and function: Aquatic

freshwater habitats, wetlands, Arctic and alpine

ecosystems;

Bogs, mires and fens - most vulnerable - 50 % affected

(concern as they are important carbon stores);

Snow, ice and frozen ground: increased number of

glacial lakes; increased ground instability in permafrost;

Approx. 10% of species at high risk of extinction for every

1°C rise in global mean temperature;

Amphibians - 45 % of species negatively affected

Current Impacts of CC on Biodiversity

Ecosystems are approaching tipping points

Shift to a new state

Difficult to predict

- Approach may be accompanied by slow, subtle

changes, vs. the rapid, drastic changes that

occur when a tipping point is reached -


Climate Tipping Points and Thresholds


Climate Change and Other Pressures: Driving

BD to Tipping Points

Source: GBO-3


Example : Grasslands exposed to over-grazing

Original state

High biodiversity

Native grass

Grass dominated system

High economic value

Altered state

Low biodiversity

Invasive species – weeds

Shrub dominate system

Low economic value

Even when grazing pressure is relaxed, there may be little change in

composition, because of the advantage of woody vegetation over grass when the

woody is dominant


Example : Coral reefs exposed to nutrient pollution

Original state

High biodiversity

Coral-dominated NPP

Medium productivity

High economic value

Biggs et al (in prep) Sourcebook in Theoretical Ecology

Altered state

Low biodiversity

Algae-dominated NPP

High primary productivity

Low economic value


Example : Lakes exposed to nutrient pollution

Can be reversible – controlled by P input; irreversible shifts between stability domains

Oligotrophic

Low primary productivity

Low nutrient content

High Drinking water quality

High biodiversity

High economic value

Eutrophic

High primary productivity

High nutrient content – algal bloom

Poor Drinking water quality

Low biodiversity

Low economic value

Anthropogenic:

nutrients input from

agriculture,

sewage…

Natural causes: in aging

lakes – building-up

concentration of plant

nutrients

Slow process – over

centuries.


Key points in understanding resilience

Climate patterns of the past will not be the same in the very near future and will

continue to fluctuate.

Reversibility and irreversibility of ecological states, and likelihood of regime

shifts.

Landscape scale is critical for maintaining resilience across different ecosystems

Management actions and land use decisions may increase or decrease resilience.


Planning at a landscape level to maintain large

scale resilience of ecosystems

Biodiversity conservation is essential as insurance to maintain resilient ecosystems and

ensure a sustainable flow of ecosystem goods and services to society.

Existing PAs are unlikely to incorporate the long-term and large-scale dynamics of

ecosystems. Conservation strategies have to incorporate land managed for human

use.

Present static PAs should be complemented with dynamic reserves, such as ecological

fallows and dynamic successional reserves, that are part of ecosystem management

mimicking natural disturbance regimes at the landscape level.


External memory

- Sources for

colonization-

Ecological Memory – key component of resilience

Internal memory

- Biological legacies –

sources for

regeneration

Dispersal filtersActing in patch

Between siteWithin site

-needed for ecosystems to reorganize after large-scale disturbances;

-composed of: species, interactions and structures that make ecosystem reorganization

possible, and its components may be found within disturbed patches as well in the

surrounding landscape.


Temporal and spatial scale in resilience planning

Developing landscape plans and policies requires a historical understanding of how the

current ecosystem arrived at its current condition.

Need for a new framework of adaptive governance that:

- embraces uncertainty and change;

- builds knowledge and understanding of ecosystem dynamics, including resilience;

- develops management practices that measure and respond to feedback

loops, including ecological thresholds; and

- supports flexible institutions and social networks in multi-level governance systems.

• (Hughes, 2005)


10 principles for maintaining landscape-scale resilience

Maintain and create large, complex patches of vegetation and small areas of native

vegetation keystone structures

Maintain structural complexity and mimic the matrix of natural vegetation patterns

Create buffers around sensitive areas or buffer patches around native vegetation

Maintain or create corridors or stepping stones to improve connectivity

Maintain landscape scale heterogeneity and capture environmental gradients

Source: Fischer, J., et al., 2006.


10 principles for maintaining landscape-scale resilience

Maintain key species interactions and functional diversity by identifying keystone

species and key seed dispersal agents

Apply appropriate disturbance regimes (e.g., fire regimes, hydrological flow regimes)

Control aggressive, over-abundant invasive species

Minimize threatening ecosystem-specific processes

Maintain species of particular concern (e.g., highly threatened/rare species)

Source: Fischer, J., et al., 2006.


Forest resilience

Resilience of a forest ecosystem is determined by the:

• diversity of species

• genetic variability within species

• regional pool of species and ecosystems

• size of forest ecosystems - the larger and less fragmented, the better

• condition and character of the surrounding landscape

Primary forests are more resilient than modified natural forests or plantations

Some degraded forests, especially those with IAS may be stable and resilient

• They can become serious management challenges if attempts are made to re-

establish the natural ecosystem to recover original goods and services

Some Forest s with naturally low species diversity have a high resilience

• Boreal pine forests : are highly adapted to severe disturbances, and their dominant

tree species have a broad genetic variability that allows tolerance to a wide range of

environmental conditions


Managing Forest ecosystems for resilience

Maintain genetic diversity in forests: by avoiding practices that select only certain

trees for harvesting based on site, growth rate, or form

Maintain stand and landscape structural complexity: using natural forests and

processes as models

Maintain connectivity across forest landscapes by reducing

fragmentation, expanding protected area networks, and establishing ecological

corridors.

Maintain functional diversity and eliminate the conversion of diverse natural

forests to monotypic or reduced-species plantations.

Reduce non-natural competition by controlling invasive species and reduce

reliance on non-native tree crop species for plantation, afforestation, or reforestation

Maintain biodiversity at all scales and components

Ensure national and regional networks of scientifically

designed, comprehensive, adequate, and representative protected areas.


Work at the Landscape level

Include all grassland types across environmental gradients in protected areas: as

we do not know precisely which grassland types will be most sensitive to CC

Protect relict and native-dominated communities: as models for habitat restoration

and help in understanding how grasslands altered vs. unaltered are affected by CC.

Minimize fragmentation by land use changes and roads: protect core grassland

habitats distant from roads and human disturbances; time road maintenance to avoid

spread of invasives; monitor roadside vegetation.

Improved Connectivity: to facilitate the migration of species in response to CC - where

it is critical for maintaining gene flow among populations of rare species

Low-intensity, sustainable grazing practices: where native species are adapted to it;

Reduce/remove grazing from sites where the predominant native species lack a long

evolutionary history of grazing by large hooved herbivores; Maintain heterogeneity of

management at the landscape and mimic grazing patterns of native herbivores;

Managing Grasslands/Steppes for resilience


Prevent and control the spread of invasive species: focus on the causes of invasion

Restoration and reintroductions of native species: IAS control, inoculations with soil

biota for native plant vigor, nutrient cycling ; restoration of native disturbance regimes

Maintenance of natural fire regimes: influences health and heterogeneity

Provide buffer zones: for shifting of populations to lands bordering reserves as

conditions inside reserves become unsuitable; act as barriers to the spread of new

invaders away from roads.

Identify and protect functional groups and keystone species: increased tolerance to

environmental extremes and recovery potential as native species richness increases.

Protect climatic refugia at multiple scales: so they can again function as refugia

during present and future CC

Managing Grasslands/Steppes for resilience (contd)


Designing conservation strategies for resilience

• Landscape Approaches

• Working at all institutional scales – international, national, local; private, public

• Maintain or restore ecological function

• Allow redundancy and inefficiency in the system

• Pay attention to disturbance – don’t exclude them; keep them from propagating

• Implement adaptive management strategies– Explicit goals; provisional hypotheses; data gathering; evidence-based decisions;

– Monitor key ‘slow variables’

– intervene in dynamics only where unacceptable and irreversible change is otherwise unavoidable


Take home messages

Resilience is not good or bad; it depends on your objective

We are currently generally unable to precisely predict the position of thresholds

leading to regime shifts, but we know they occur

We do know some generalised attributes of systems that promote or erode

resilience

High efficiency and high connectivity reduce resilience to external shocks

Functional diversity and redundancy increase resilence


THANK YOU!!!

Managing Ecosystems to improve resilience (UNDP presentation)

Self Improvement

Transcript of Managing Ecosystems to improve resilience (UNDP presentation)