《景观生态学》（英文版） LANDSCAPE ECOLOGY SREM 3011 LECTURE 10

LANDSCAPE ECOLOGY SREM 3011 LECTURE 10 Dr Brendan Mackey Department of Geography The Australian National University

LANDSCAPE ECOLOGY SREM 3011 LECTURE 10 Dr Brendan Mackey Department of Geography The Australian National University

Communities criterion: Integration of complex behaviour of biota in a given area Integration results in cohesion and a degree of self-regulation changes physical environment eg rainforest closed canopy +ve and -ve population interactions Ecosystem criterion: Biota are explicitly linked to the abiotic world of their physical environment Cycles and pathways of energy and matter water nutrients carbon Organisms, populations, communities are viewed in terms of their ecosystem function process rates are critical

Communities criterion: - Integration of complex behaviour of biota in a given area - Integration results in cohesion and a degree of self-regulation : changes physical environment - eg. rainforest closed canopy - +ve and -ve population interactions Ecosystem criterion: - Biota are explicitly linked to the abiotic world of their physical environment - Cycles and pathways of energy and matter : water, nutrients, carbon - Organisms, populations, communities are viewed in terms of their ecosystem function - process rates are critical

Nested vs Non-nested Hierarchies The human body is a nested hierarchy The Soviet Union was a non-nested hierarchy it was a hierarchy because of the 'chaln-of. command it is structured by the flow of information the President is a low frequency, large-scale phenomena the foot soldier is a high frequency, small-scaled phenomena

Nested vs Non-nested Hierarchies The human body is a nested hierarchy. The Soviet Union was a non-nested hierarchy. - it was a hierarchy because of the ‘chain-of￾command’ - it is structured by the flow of information - the President is a low frequency, large-scale phenomena - the foot soldier is a high frequency, small-scaled phenomena

Conventional levels of biological/ecological organization Level 8 - Biosphere Planet Level 7 -Biome Region Level 6 -Landscape Level 5-------.-Ecosystem Subcatchment Level 4-....Community Level 3 -Population Patch Level 2.--------Organism Sit Level1--------------Cell

Conventional levels of biological/ecological organization Planet Region Subcatchment Patch Site

Types of ecological entity and their inter-relationships at different scales of observation = organism; P=population;C= community; E= ecosystem; L=landscape; B= biome Small scale Large scale Types of ecological entities are really criteria for defining ecological phenomena All criteria can be applied at any scale Criteria distinguish foreground from background

Types of ecological entity and their inter-relationships at different scales of observation O = organism; P = population; C = community; E = ecosystem; L = landscape; B = biome • Types of ecological entities are really criteria for defining ecological phenomena • All criteria can be applied at any scale • Criteria distinguish foreground from background Small scale Large scale

Example of organism providing context for ecosystem Organism Cow Ecosystem Cow's rumen Example of organism providing context for population Organism Dog Population Fleas Example of organism appearing to have characteristics of a population Population or Banyan tree Organism?

Example of organism providing context for ecosystem: Organism Cow Ecosystem Cow’s rumen Example of organism providing context for population: Organism Dog Population Fleas Example of organism appearing to have characteristics of a population Population or Banyan tree Organism?

A cross-section of banana tree identifies that the trunk is almost entirely fleshy sheathing leaf bases, not woody stem What is a tree?

A cross-section of banana tree identifies that the “trunk” is almost entirely fleshy sheathing leaf bases, not woody stem What is a tree?

The army of alexander the great camped under a single banyan tree Both banyans and aspen clones have stems connected: banyans above the ground, aspen below ground oen Banyan What is an organism? What is a population?

The army of Alexander the Great camped under a single banyan tree. Both banyans and aspen clones have stems connected: banyans above the ground, aspen below ground. What is an organism? What is a population?

In a detailed study of the environmental impact of a dam on the Kickapoo River, the Center for Biotic Systems University of Wisconsin-Madison, collected: A, maps of the fine detail of the stream patterns in the entire watershed of approximately 15 by 25 miles and then aggregated these small rivulets into successively larger watersheds within the entire Kickapoo watershed system B Fifth order watershed C Sixth order watersheds What is a landscape?

In a detailed study of the environmental impact of a dam on the Kickapoo River, the Center for Biotic Systems, University of Wisconsin-Madison, collected: A, maps of the fine detail of the stream patterns in the entire watershed of approximately 15 by 25 miles and then aggregated these small rivulets into successively larger watersheds within the entire Kickapoo watershed system. B Fifth order watershed. C Sixth order watersheds. What is a landscape?

For a mineral nutrient to pass once around a nutrient cycle, it must pass in and out of the biotic component of the ecosystem several times in one year. Accordingly, biota are not often a simple subs ystem of process/functional ecosystems CIRCULAR COMPARTMENT abiotic Biotic FALL worn eats leaf defecates ngus bsorbs nutrients fungus die enters soil ents Roots die WINTER SPRING Roots grow down old recover nutnents 2飞 Rhizosphere SUMMER When is biota part of an ecosystem process?

For a mineral nutrient to pass once around a nutrient cycle, it must pass in and out of the biotic component of the ecosystem several times in one year. Accordingly, biota are not often a simple subsystem of process/functional ecosystems. When is biota part of an ecosystem process?