Resource use in the long-term can only be sustainable if the biodiversity and food
web of the ecosystems remain complete, i.e. including natural processes and conditions of immigration and emigration. Such natural processes are the precondition for
resistance and resilience of the system and minimizes the risk that species become
extinct.
Migratory populations and species try to optimize foraging efficiency, minimize
predation, avoid pathogens, and be as energy-efficient as possible. All native
species, humans and neobiota belong to one or more ecosystems. With respect to
resource use, there is no general difference between an invading exotic and a native
species: both need space and use resources. Migration of individuals and species,
and the adherence of distance among individuals, can be useful for the optimization
of the ecosystem’s resource use.
Biomass, productivity and species diversity are important components of every
ecosystem. Changes in these components reflect changes in the
compartmentalisation and resource use of the ecosystem.
Resources are used by the native species of the ecosystem, as well as by migrating
species including humans, and invasive species when they arrive. Humans—like all
other species—influence ecosystems in various ways, with differential effects on
biomass, productivity and species diversity. In every case, these influences will
affect the use and cycling of nutrients and energy within the ecosystem.
Under such dynamic conditions, ecosystems are adapting resource use continuously by adjusting the combination of these components. Productivity is the driver of
recent conditions and a precondition for biomass; biomass means storage and is a
precondition for productivity; species diversity can increase through immigration
and evolution, and decrease from emigration and extinction. In general, ecosystems
have smaller productivity, biomass and species diversity during dry or cold periods,
than during wet or warm periods.
In highly dynamic environments—such as coastal regions or rivers—high values
of biomass cannot be realized. On the other hand, forest ecosystems with a large
volume of old trees and biomass will never be extremely productive. Also, the
diversity of individuals and species can be interpreted as an adaptation to the use
of resources. Ecosystems with high diversity—species and/or individuals—are more
productive than ecosystems with poorer diversity under comparable ecological
conditions.
Humans influence ecosystem functions in different ways, with different effects on
biomass, productivity and species diversity. In most cases, changes to ecosystem
functions have consequences for species diversity, which usually decreases, but—
dependent on the spatial scale—sometimes increases.
We ask the question “is it possible to estimate the effects of humanity’s exploitation of ecosystems?” Furthermore, we promote the hypothesis that it might be
difficult, if not impossible, for humans to reduce their overall exploitation, and
overall production of energy, goods and waste seriously. In general, species assemblages try to optimize their resource use as compromise between short-term use and
long-term survival (Theory on Assembly Optimization, TAO). Thus, we can ask
‘what could a solution in a worst-case scenario be?’
Land Use Change and the Future of Biodiversity
461
web of the ecosystems remain complete, i.e. including natural processes and conditions of immigration and emigration. Such natural processes are the precondition for
resistance and resilience of the system and minimizes the risk that species become
extinct.
Migratory populations and species try to optimize foraging efficiency, minimize
predation, avoid pathogens, and be as energy-efficient as possible. All native
species, humans and neobiota belong to one or more ecosystems. With respect to
resource use, there is no general difference between an invading exotic and a native
species: both need space and use resources. Migration of individuals and species,
and the adherence of distance among individuals, can be useful for the optimization
of the ecosystem’s resource use.
Biomass, productivity and species diversity are important components of every
ecosystem. Changes in these components reflect changes in the
compartmentalisation and resource use of the ecosystem.
Resources are used by the native species of the ecosystem, as well as by migrating
species including humans, and invasive species when they arrive. Humans—like all
other species—influence ecosystems in various ways, with differential effects on
biomass, productivity and species diversity. In every case, these influences will
affect the use and cycling of nutrients and energy within the ecosystem.
Under such dynamic conditions, ecosystems are adapting resource use continuously by adjusting the combination of these components. Productivity is the driver of
recent conditions and a precondition for biomass; biomass means storage and is a
precondition for productivity; species diversity can increase through immigration
and evolution, and decrease from emigration and extinction. In general, ecosystems
have smaller productivity, biomass and species diversity during dry or cold periods,
than during wet or warm periods.
In highly dynamic environments—such as coastal regions or rivers—high values
of biomass cannot be realized. On the other hand, forest ecosystems with a large
volume of old trees and biomass will never be extremely productive. Also, the
diversity of individuals and species can be interpreted as an adaptation to the use
of resources. Ecosystems with high diversity—species and/or individuals—are more
productive than ecosystems with poorer diversity under comparable ecological
conditions.
Humans influence ecosystem functions in different ways, with different effects on
biomass, productivity and species diversity. In most cases, changes to ecosystem
functions have consequences for species diversity, which usually decreases, but—
dependent on the spatial scale—sometimes increases.
We ask the question “is it possible to estimate the effects of humanity’s exploitation of ecosystems?” Furthermore, we promote the hypothesis that it might be
difficult, if not impossible, for humans to reduce their overall exploitation, and
overall production of energy, goods and waste seriously. In general, species assemblages try to optimize their resource use as compromise between short-term use and
long-term survival (Theory on Assembly Optimization, TAO). Thus, we can ask
‘what could a solution in a worst-case scenario be?’
Land Use Change and the Future of Biodiversity
461