Applied Ecology
Introduction lecture
More intense color indicates a greater threat
e.g., Habitat loss and fragmentation are less intense at the moment, as we have lost most habitat
already (peaked in the 1920’s-30’s)
Introduction to applied Biogeochemistry for Applied Ecology
Biogeochemistry
- The study of mineral cycling and transfer, water cycling, and of the relationships between
organisms and their environment
- Scales: Globe – Biome – Landscape – Ecosystem - Habitat
- Linking disciplines: Ecology – Microbiology – Geochemistry – Hydrology
- Linking different spheres: Hydrosphere – Geosphere – Ecosphere - Atmosphere
Linking different spheres
- Study: Cycling of elements (e.g., C, N, P, S) and water
- Implications: Resources and conditions for organisms
- Practical implications for: climate change, eutrophication, acidification, toxicity, etc.
- i.e., changes in conditions and resources for organisms; often anthropogenic (man-made)
- Effects on biodiversity, ecosystem functioning and services
Applied Ecology: initially ‘trial and error’ approach
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, - Often no clear goals/ targets (e.g., back to what/when?); evaluation very difficult
- Correlations rather than causal relations
- Level of success highly variable
- Difficult to reproduce; unpredictable
- Difficult to extrapolate to other areas/ systems I climates
We often start with correlation and then check with causation using experiments
- Correlation does not equal causation: e.g., stork and baby correlation
- Could test this by e.g., removing all storks or checking in another location (however,
implications, such as could say only Berlin storks are causing extra baby deliveries)
- Best way is to do experiments to find these causal relationships
Regulation of decomposition / mineralization
- Decomposition: metabolic breakdown of organic matter to simple organic and inorganic
molecules, generating energy
- Mineralization: transition of a nutrient or another substance from an organically bound form to
a water-soluble inorganic form, as a result of biological or inorganic chemical processes
- Temperature: higher temperature = higher rates
- Nutrient concentrations: higher = higher decomposition and mineralization rate = more
nutrients available
- Concentration / degradability organic compounds (electron donors: acetate, lactate, ...)
- Phenolic compounds: higher phenolic = lower rates
- Alkalinity (acid neutralizing capacity, ANC) = lower rates
- Salinity (Cl- ) = lower rates
- Electron acceptor availability (microbial redox reaction)
Oxidation states
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,Gibb’s free energy
Glucose is a very good electron donor (negative E0) and 02 a good electron acceptor (positive E0)
This is importance – check for exam
In peat you have low decomposition rates
- Anaerobic conditions due to waterlogged (02 is the good electron acceptor)
- Low pH (acidic)
Wetland versus dryland (upland)
- Permanent or periodical (riparian) waterlogging / flooding
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, - (Permanent/periodical) anaerobic / anoxic conditions
→ Climate change
- All this stored carbon will be released in a short period of time (stored for a long time)
Under moist conditions the decomposition rates are even higher than under dry conditions (may seem
controversial as waterlogged conditions limit decomposition); nutrient input is lower, microorganisms
not adapted to this system. Organisms also need this water for their biochemistry. Thus, there is an
optimum – extreme conditions are often not optimal (think about optimal ‘normal’ curve)
Wetland versus dryland (upland)
- Permanent or periodical (riparian) waterlogging / flooding
- (Permanent/periodical) anaerobic / anoxic conditions
Redox potentials
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