LANDSCAPE ECOLOGY SREM 3011 LECTURE 11 Dr Brendan Mackey Department of Geography The Australian National University
LANDSCAPE ECOLOGY SREM 3011 LECTURE 11 Dr Brendan Mackey Department of Geography The Australian National University
2. Context Low frequency behaviour allows upper level to be the context of lower level context is either spatially larger or more constant over time than lower level the fact that summer follows spring sets the context for plant growth that which is constant NB unpredictability can be"constant"and therefore context
2. Context - Low frequency behaviour allows upper level to be the context of lower level - context is either spatially larger or more constant over time than lower level : the fact that summer follows spring sets the context for plant growth : that which is constant NB unpredictability can be “constant” and therefore context
B Cells aggregated to form a tissue are an example of a lower level being contained by a higher level C Food chain hierarchies represent non-nested systems where the higher levels do not contain the lower levels cells are contained(nested) food chains are non-nested
B Cells aggregated to form a tissue are an example of a lower level being contained by a higher level. C Food chain hierarchies represent non-nested systems where the higher levels do not contain the lower levels. • cells are contained (nested) • food chains are non-nested
Carnivore Carnivore x Grazer Grazer Plant Plan Plant @分
3. Containment The constituent parts are contained within each other Higher levels contain(bound)lower levels The organism contains the higher frequency components cells turn over faster than the organism Nested contained systems tend to be scale-dependent organIsms, populations, species Definition of non-nested hierarchies more observer. dependent communities ecosystems EARTH??
3. Containment - The constituent parts are contained within each other - Higher levels contain (bound) lower levels - The organism contains the higher frequency components : cells ‘ turn over’ faster than the organism - Nested contained systems tend to be scale-dependent : organisms, populations, species - Definition of non-nested hierarchies more observerdependent : communities : ecosystems EARTH??
Constraint For non-nested hierarchies, frequency and constraint are most important characteristics Constraint'can be a 'passive condition tree canopy provides shade and therefore constrains seedling regeneration Constraint allows ecological systems to be predictable the level in question is constrained by an envelope of permissible behaviours Name of the game"in landscape ecology(or science generally) is to find constraints that enable(spatial) prediction
4. Constraint - For non-nested hierarchies, frequency and constraint are most important characteristics - ‘Constraint’ can be a ‘passive condition’ : tree canopy provides shade and therefore constrains seedling regeneration - Constraint allows ecological systems to be predictable : the level in question is constrained by an envelope of permissible behaviours - “Name of the game” in landscape ecology (or science generally) is to find constraints that enable (spatial) prediction
5. Emergent properties Characteristics occur which are not apparent from examining their constituent parts plant behaviour not predictable from looking at individual cellls population viability requires understanding of matrix (patches corridors) not just individual organIsms c ecosystem function cannot be predicted from examining one species/population forest canopy structure is an interaction of all the plants in a stand/patch
5. Emergent properties - Characteristics occur which are not apparent from examining their constituent parts : plant behaviour not predictable from looking at individual cells : population viability requires understanding of matrix (patches + corridors) not just individual organisms : ecosystem function cannot be predicted from examining one species/population : forest canopy structure is an interaction of all the plants in a stand/patch
6. Concept of a holon Each entity in a level of a hierarchy is a component of a higher level and simultaneously sets the context Constrains lower level an organism contains cells and is a member of a population a population contains organisms and is part of a community Therefore, ecological systems require multi-scaled analysis to be fully described. No single level of investigation will account for ecology of a landscape populations, species, communities, ecosystems all constitute valid"units"of spatial analysis of landscape ecology
6. Concept of a Holon - Each entity in a level of a hierarchy is a component of a higher level and simultaneously sets the context /constrains lower level : an organism contains cells and is a member of a population : a population contains organisms and is part of a community Therefore, ecological systems require multi-scaled analysis to be fully described. No single level of investigation will account for ecology of a landscape. : populations, species, communities, ecosystems all constitute valid “units” of spatial analysis of landscape ecology
O COMPLEX ADAPTIVE SYSTEMS location specific, local interactions between competitive agents are an important source of higher level system response external environmental conditions can either contain or constrain agent behaviour +ve and -ve feedbacks can influence 'external environment at all scales from nano to global ecological systems are adaptive to the extent that the biological agents are adaptive
COMPLEX ADAPTIVE SYSTEMS location specific, local interactions between competitive agents are an important source of higher level system response external environmental conditions can either contain or constrain agent behaviour +ve and -ve feedbacks can influence ‘external’ environment at all scales from nano to global ecological systems are adaptive to the extent that the biological agents are adaptive
POPULATIONS EXIST WITHIN ECOLOGICAL SYSTEMS internally generated feedbacks emergent pattern external drivers / local effective interacting environment agents
POPULATIONS EXIST WITHIN ECOLOGICAL SYSTEMS: external drivers local interacting agents effective environment emergent pattern internally generated feedbacks