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Adaptations of seasonal and Adaptations of seasonal and temporary wetland communitiestemporary wetland communities
Definitions:Definitions:
Seasonal wetlandsSeasonal wetlands are nontidal wetlands are nontidal wetlands that are flooded for that are flooded for extended periodsextended periods in in the growing season.the growing season.
Temporary wetlandsTemporary wetlands are nontidal wetlands are nontidal wetlands that contain surface water for that contain surface water for brief periodsbrief periods in the growing season.in the growing season.
Intermittent watersIntermittent waters – become dry at times of – become dry at times of the year that are more or less predictable.the year that are more or less predictable.
Episodic watersEpisodic waters – are water-filled on a more – are water-filled on a more or less unpredictable basis.or less unpredictable basis.
Characteristics:Characteristics:
Lentic watersLentic waters
Closed environmentClosed environment
Lack of fishLack of fish
Presence of fairly shrimp andPresence of fairly shrimp and
tadpole shrimptadpole shrimp
WinterWinter
Verna pools Verna pools Seasonal marshesSeasonal marshesFlooded grasslandsFlooded grasslandsPlayasPlayas Spring SpringDesert depressionsDesert depressionsRock poolsRock pools
SummerSummer
Invertebrate and plant communities are Invertebrate and plant communities are affected by duration, timing, and frequency affected by duration, timing, and frequency
of flooding.of flooding.
Adaptations are:Adaptations are:
Morphological Morphological
PhysiologicalPhysiological
Behavioral.Behavioral.
Three main evolved strategies for Three main evolved strategies for surviving the dry season:surviving the dry season:
Life history modificationLife history modification
Physiological tolerancePhysiological tolerance
MigrationMigration
#1 Life History Modification#1 Life History Modification
Wetland invertebrates exhibitWetland invertebrates exhibit:: High powers of dispersalHigh powers of dispersal Rapid growthRapid growth Short life-spanShort life-span Small sizeSmall size Opportunistic/Generalistic feedingOpportunistic/Generalistic feeding
Wetland plants exhibit:Wetland plants exhibit: Rapid growth/reproduction – (8 to12 weeks)Rapid growth/reproduction – (8 to12 weeks)
Fairy ShrimpFairy Shrimp
16 day life cycle16 day life cycle
1/2” – 1” in size1/2” – 1” in size
Feed on algae, bacteria, Feed on algae, bacteria, protozoa, dead tadpoles protozoa, dead tadpoles and mollusks. and mollusks.
Easily dispersed by wind Easily dispersed by wind or water fowl.or water fowl.
#2 Physiological Tolerance #2 Physiological Tolerance
Synchronous life cycle.Synchronous life cycle.
Diapause during stagesDiapause during stages
in the life cycle thatin the life cycle that
coincides with drought.coincides with drought. Delta Green Ground BeetleDelta Green Ground Beetle Elaphrus viridisElaphrus viridis
Production of dormant egg and seed Production of dormant egg and seed propagulespropagules::
PlantsPlants::
Wetland plants will germinate with the firstWetland plants will germinate with the first
winter rains.winter rains.
Grow while the pool is full of water.Grow while the pool is full of water.
Flower and set seed as the waterFlower and set seed as the water
evaporates.evaporates.
InvertebratesInvertebrates::
Wetland invertebrates lay their eggs in the Wetland invertebrates lay their eggs in the sediment.sediment. Development is allowed to occur in the Development is allowed to occur in the absence of water.absence of water. Emergence occurs when the pond floodsEmergence occurs when the pond floods again.again.
Benefits of a long-lived egg and Benefits of a long-lived egg and seed bankseed bank
Maintain genetic, species Maintain genetic, species and community diversity.and community diversity.
Food for migrating Food for migrating waterfowl and shorebirds.waterfowl and shorebirds.
Predator and competitor Predator and competitor free environment.free environment.
#3 Migration#3 Migration
Divided into two forms:Divided into two forms:
ActiveActive – Requires power of flight. Seen – Requires power of flight. Seen mostly in insects.mostly in insects.
PassivePassive – used by smaller plant and – used by smaller plant and animal species that are not able to migrate animal species that are not able to migrate unassisted.unassisted.
Active migrationActive migration
Pantala flavescensPantala flavescens
The Wandering GliderThe Wandering Glider
Breeds in temporary ponds, Breeds in temporary ponds, exhibits long-distance exhibits long-distance dispersal.dispersal.
At emergence adults fly At emergence adults fly upward and are upward and are transported by the wind. transported by the wind.
Passive MigrationPassive Migration
Wind and surface Wind and surface drainage dispersal.drainage dispersal.
Transportation by Transportation by waterfowl.waterfowl.
Transportation by Transportation by insects.insects.
Importance of seasonal and Importance of seasonal and temporary wetlandstemporary wetlands
Increased fitness demands lead to greater Increased fitness demands lead to greater genetic diversity.genetic diversity.
Habitat for distinct species that are not found Habitat for distinct species that are not found elsewhere.elsewhere.
Maximizing the gene pool of species that Maximizing the gene pool of species that occur in both temporary and permanent occur in both temporary and permanent waters.waters.