Lecture 1-5

Corridor

A strip of a particular landscape element that differs from the adjacent land on both sides.

Metric Levels (or resolutions)

A. Individual B. Patch C. Mosaic D. Landscape

Landscape Metrics

Common ways to measure changes in either landscape composition or configuration

network

Corridors of single types intersect to form a...

Patch Dynamics

Five causes of vegetation patch creation.

Catchment Water Budgets

P = R + E + ΔS P = precipitation R = runoff E = evapotranspiration ΔS = change in storage

Patches

Relatively homogenous nonlinear area that differs from its surroundings

Mosaic

Spatially heterogeneous pattern of patches, corridors & matrix composed of a mix of landscape elements

Matrix

The dominant vegetation or land-use type is the ....... Characterized by extensive cover, high connectivity & major control over landscape dynamics.

Landscape Function

The interaction between landscape elements.

Landscape composition

The relative amounts of each landscape element or habitat type contained in the landscape

Interior or core

Total patch minus edge habitat

Environmental patch

caused by natural variation in soil and water flow across the landscape, happen over a long period of time (100-1000 millions of years) these can drive patchiness although more stable.

Landscape structure

is the spatial pattern of landscape elements and the connections between the different ecosystems or landscape elements

Boundary

line that separates edges from adjacent landscape elements

Spatial extent (Spatial scale)

size of study area

Hydrological Cycle

water cycle

Boundary Types & Edges

• Gradient Boundary: Gradual "soft" difference in concentration of existing components -Ecotone • Hard Boundary: A sharp & abrupt "hard" boundary that separates patches &/or corridors (Generally more common than gradient boundaries)

Configuration Metrics

• Isolation Metrics (e.g.,nearest neighbour distance) • Contagion/Interspersion Metrics (e.g., clumpiness)

Composition Metrics

• Proportional abundance of each feature type. • Richness = number of different feature types. • Evenness = relative abundance of different feature types, measuring dominance or equity. • Diversity = composite measure of richness and evenness (e.g., Shannon diversity metric).

Edge Effects

• Unique set of species that are found only near the border • Generally related to microclimates of edges • Can be very different from the interior • A forest edge may see higher or lower tree density • Drier, higher light intensity/evaporation environment • Only certain plants or animals may exist • Time-dependent • May also see a greater incidence of weed & pest species • E.g. natural ecosystems may observe an invasion of weedy species from adjacent human landscapes • Different nutrient & water values • Greater inputs of P/N in natural ecosystem located adjacent to agricultural areas • Greater herbivory & predation • Edge of forest environment observes easier access by large herbivores • Little cover for prey species at the edge of a forest

Physical Landscape Processes

(e.g., flows of water, material and energy) that shape landscape structure (geomorphology)

Biotic edge effects

(predation, diseases, weeds, behaviour, plant and animal species composition, breeding success, dispersal)

Landscape structure

.....also influences physical process that then interact with ecological processes to drive ecosystem function (e.g., freshwater flows, climate, fire, energy flows, etc.)

Corridor

A strip of a particular landscape element that differs from the adjacent land on both sides

Drivers of Landscape Change

Agriculture is the most spatially extensive driver of landscape change • Mining • Logging • Urbanisation • Infrastructure • Strong winds (cyclones, hurricanes and tornados) cause localised damage on a scale of 1000s of hectares. • Fire is an important modifier of landscape structure. Changing fire regimes contribute to changing fauna distribution

distance species disperse may be affected by....

Crossing or not crossing the boundary , Displacement or the transfer, Arrival at the new resource

dual/multipurpose networks

Different networks overlap & are imprinted on one another

Processes Affecting Biological Populations

Habitat loss, Landscape fragmentation, Species-area relationships, Species movement and landscape connectivity, Spatial population dynamics

Patch-Corridor-Matrix Model

Here there is a clear contrast between human-defined patches and the remainder of the landscape. Related to the theory of island biogeography

Landscape

Heterogeneous land area composed of clusters of interacting ecosystems that are repeated in a similar form throughout.

Patch Shapes

High perimeter: area ratio Less interior habitat & more edge effects Low perimeter: area ratio More interior habitat & lower edge effects

Landscape Ecology and Dispersal

Human modification of landscapes and land cover can play an important role in dispersal/movement. • Landscape fragmentation can form barriers e.g. roads, patch isolation. • Can enhance movement of exotic plants and animals • Landscape ecology can address dispersal success with the conservation or restoring of new areas of habitat for species of interest through • Landscape planning • Invasive species management • Reserve design • Conservation outside nature reserves

Continuum or Gradient Model

It conceptualises landscapes as having variation across gradients of food, shelter, space and climate. Landscape heterogeneity does not exist in discrete patches, but rather exists as a continuously varying property of the local environment and landscape.

Hierarchical Patterns of change

Landscape change operates simultaneously across different hierarchical scales Change on site can effect change on patches ewhich can effect change on the landscape.

Landscape Features

Landscapes can be conceptualised as consisting of 3 types of interacting elements: • Patches, Corridors, Matrix (patch, corridor, matrix model)

Species-Area Relationships

Larger areas have more species than smaller areas This is often called one of the few ecological laws S = CA^z S= number of species, A= area, C and z are constants to be estimated from data

Patch

Relatively homogenous nonlinear area that differs from its surroundings.

Patch-Mosaic Models

Represents the landscape as a mosaic of discrete patches of different composition and habitat quality. Landscapes are viewed as spatially complex, heterogeneous assemblages of patch types, which can not be simply categorized into discrete elements such as patches, matrix, and corridors.

Still need to study from lecture note in note book, slide no. 10, 12, 13 wasnt included in here. Also the case study, 14 - 25 (check wheter the case study was till slide 25 or is that other info that needs to be added to this note as well)

Slide 10: urbanization to hydrology: Tree cover helps store water in soil and acuifer and high level of evapotranspiration as urbanization increases there is less evapotranspiration and more runoff because the loss of tree cover(it becomes more impervious). Therefore, less storage in the system. This effect things like flooding, microclimate and long term storage of water. This can have big impact to local and regional levels. Slide 12 and 13:Change in the evapotranspiration across the globe in the different basins.(over the 50-100 year period: It is negative in most place, it is caused by combination of climate/precipitation change. Less in evapotranspiration more in run off. Landscape effect of change in landscape use (according to this study) can be almost as big as climate effect but they can be positive or negative In slide 13 changes in Asia to be positive may be related to the change in the practice of Agriculture. Slide 14 to 18 : Case study reduce in amount of freshwater due to agriculture in those areas. Seasonal Flooding did not happen anymore which can effect biological function. There were much less freshwater flow(? slide 16) Marsh sizes reduced and only left with small patches, and there were higher distance between them Anyhow,WHAT WAS THE POINT OF THIS EXAMPLE WA slide 18-25

Corridor

Strips that differ from surroundings & permeate the landscape • Streams, ridges & animal trails (natural) • Roads, trails, powerlines & ditches (human) Corridor structure and Function Width characteristics • Steep ecological gradients from side to side • Generally, a much narrower width than patches & much greater potential for edge effects Length characteristics • Long consistent environment that can stretch large distances • Connects separate patches or matrices & provides an effective dispersal route

Landscape Change

The alteration in structure and function through time.

Landscape Change

The alteration of the structure and function of the landscape mosaic over time

Matrix

The dominant vegetation or land-use type, • Characterized by extensive cover, high connectivity & major control over landscape dynamics

Edge

The outer band of a patch that is environmentally significantly different from the interior of the patch.

Landscape configuration

The physical layout of all landscape elements or habitat patches in the landscape

Landscape Structure

The spatial relationship between distinctive landscape elements.

Habitat fragmentation

a landscape-scale process and involves the breaking apart of a specific habitat (e.g. forest) into smaller patches A large expanse of habitat is transformed into a number of smaller patches, isolated from each other by a matrix of habitats unlike the original. (configuration)

disturbance or perturbation

an event that causes a significant change in the structure and function of an ecosystem or landscape

Boundary flows

are the movement or exchange of organisms, matter and energy across edges.

Functional connectivity (Two types of connectivity)

ecological processes e.g seed dispersal, animal movement and dispersal

Loss of habitat

generally negative and the most important driver of biodiversity (this is related to landscape COMPOSITION)

Introduced patch

human created patches (e.g. building, People planting crops or trees) happen over intermediate time scale

Structural connectivity (Two types of connectivity)

human perspective of landscapes patterns

Process of fragmentation

increase in number of patches, decrease in patch sizes, and increase in isolation of patches

Landscape Ecology

integrates humans with natural ecosystems and brings a spatial perspective to such fields as natural resource management, conservation, and urban planning.

Physical flows

involve movement of wind, water, heat energy and nutrients (e.g. fertiliser)

Biological flows

involve the movement of seeds, spores, insects, ground-moving animals and flying-animals

Fire (landscape process)

is a key driver of ecological and landscape processes in Australia and elsewhere in the world. It can create heterogeneity and patchiness in landscapes but also responds to landscape composition and configuration.

Functional Landscape Connectivity

is the degree to which the landscape facilitates or impedes movement of organisms among source patches

Broad/coarse scale

large study area, or measurement size, that is relatively large E.g. Broad-scale continental map or image

Wavy (Types of network, landscape connectivity)

migration paths, braided streams

Functional grain

provides a spatially explicit, organism-centered view of landscape structure size of the smallest landscape element that the organism recognizes

Temporal Scale

relating to time For example,

Patch

relatively homogenous area that differs from its surroundings • Can be: Large or small, rounded or elongated & straight or convoluted boundaries.

Landscape connectivity

results from a complex interaction between the dispersal behaviour of each particular individual and the level of fragmentation of the landscape

Dendritic (branched) (Types of network, landscape connectivity)

rivers, streams

Rectilinear (Types of network, landscape connectivity)

roads, vegetation shadelines

Regenerated patch

similar to remnant patches but it has been disturbed but has regrown

Remnant patch

small areas that escape disturbance

Small/fine scale

small study area, or measurement size, that is relatively low E.g. map of botanic garden

Spatial resolution (grain) (Spatial scale)

smallest element perceived or measured

Abiotic edge effects

temperature, wind, light, moisture, nutrient exchanges). Can extend 10s-100s metres from the edge

Ecosystem services

the aspects of ecosystems utilized (actively or passively) to produce human well-being. E.g. pollination, carbon sequestration and human recreation.

Landscape Function

the flow of organisms (plants e.g. seeds, spores; and animals), energy and matter within and across the landscape.

Ecologically core habitat

the largest circle that can fit within the interior (lobed shape)

Evapotranspiration

the process by which water is transferred from the land to the atmosphere by evaporation from the soil and other surfaces and by transpiration from plants.(not on lecture slide this definition)

Habitat loss

the reduction in the amount or area of specific habitat type (forest) in the landscape. (composition)

One Large Patch or Several Small Patches?

• Depends on species behaviour/life history attributes • Depends on patch quality and its connectivity • Depends on matrix and its habitat quality • Depends on disturbances

Advantages of Small Patches

• Habitat & stepping stones for species dispersal & re-colonization after local extinction of interior species • Provides escape cover from matrix predators • Increases matrix heterogeneity and diversity • Can be aesthetically appealing to humans • Can provide habitats for rare species

Spatial Population Dynamics

• In fragmented landscapes individuals may need to move further to obtain sufficient food or social interactions. • Home ranges may contract in smaller patches, so ranges overlap and densities are higher. • Animals may need to feed in more exposed areas where they are vulnerable to predation. • Ability of individuals to disperse is decreased with important consequences for reproduction and genetic exchange.

Fragmentation gives more positive effects (Fahrig Meta-Analysis)

• Increased connectivity (stepping stone patches, more edge) • Higher diversity of habitats • Positive edge effects • Risk spreading • Reduced competition

Perimeter

• It's length linked to patch shape and amount of edge • Can act as a filter/boundary for species movement

Theory of Island Biogeography

• Large Islands have more species than Small Islands • Islands close to mainland have more species than distant islands • Species composition does turnover but there is a equilibrium number of species • Has been applied to conservation strategies by viewing natural reserves as islands

Advantages of Large Patches

• Large patches better able to sustain interior-dwelling species populations • Core interior habitats provide cover from predators • Provides regulated microhabitats for multi-habitat species • Less prone to matrix-based disturbance regimes • Buffer against extinction in environmental change • better at water quality protection for lakes and reservoirs • Reduces the speed of overland flows of water and nutrients

Landscape Change and Hydrology

• Precipitation Change • Run off • Landscape conditions of water storage and water phase • All of this lead to temperature change

Important features for connectivity

• Stepping stones (patches) • Wildlife corridors • Matrix permeability

Land-cover Effects on Hydrology

• Vegetation slows the flow of water and reduces runoff • Permeability of soils and surface layer influence infiltration and storage and therefore runoff • Land cover influences transpiration (loss of forest cover reduces transpiration, some agricultural land uses can increase transpiration) • Energy exchange in different land covers affect evaporation

Disturbance patch

• alteration or disturbance of a small area • some disturbance that happens over short time period can be big or small (e.g. cyclones, fire)

What landscape structure influences

• where species occur and how they use the landscape • Vegetation structure and composition • Environmental flows e.g. water, soil erosion and deposition • How changes in the landscape affect these functions

Landscape Elements Affecting Fire

● Slope steepness: affects heat-transfer rate and fire spread. Steep slopes in the direction of wind facilitate spread. ● Aspect: affects solar incidence that influences soil moisture and fuel temperature. ● Land cover: effects the amount and spatial arrangement of fuel that influences ignition, heat transfer rates, and fire spread. Tree density and canopy important. ● Topographic barriers: affect connectivity and the spatial pattern of fire spread (e.g., cliffs, fire breaks, certain land covers). (try memorising them individually)