Groundwater:a living resource
Fauna discovered in 1880s by Charles Chilton at Eyreton, Canterbury
NZ:•Live in all groundwaters throughout NZ•Some highly local•Currently >100 named species, most endemic•Another >90 await description•Anticipate >500 species
Groundwater biodiversity:high diversity
Groundwater biodiversity:in all aquifer systems
N. Boustead, NIWA
Groundwater biodiversity:curiosities or ecological keystones?
Groundwater ecosystemconceptual food web
water percolating from soil surface
Dissolved org CParticulate org C
Groundwater surface
Org C in biofilms
browsed by animals
predatorsfaeces,death
microbes?
D org CP org C
microbes
net losses as CO2
from respiration
Excessive loadings kill the animals
Sewage effluent: effects
0
50
100
150
200
250
-180 -100 12 20 400 430
distance from ponds (m)
nu
mb
ers
/20 l
0
100
200
300
400
500
600
-180 -100 12 20 400 430
distance from ponds (m)
nu
mb
ers
/20 l
Mollusca
Nematoda
Annelida
Acarina
Ostracoda
Syncarida
Nauplii
Copepoda
Amphipoda
SummerIncreases
•copepodsDecreases
•Acarina
AutumnIncreases
•annelids,•amphipods•Acarina &•nematodes
Decreases •copepods
Carbon & nutrients from land use:
a subsidy/stress gradient in groundwater ecosystems
Invertebrate biomass
Organic enrichment
Dissolved oxygen
Ecosyste
m function
Organic carbon
Excess organic matter &/or reduced dissolvedoxygen lead to dead stygofauna &
clogged, anoxic sediments
Groundwater ecosystem services:vital to aquifer sustainability
Groundwater is a living resource
– Contains significant biodiversity
Performs vital ecological services
– Consumes some potentially harmful microbes
– Removes organic carbon from sediments
– Stygofauna feeding and movement:
• Maintains aquifer flow and water quality
• Enhances surface water quality
Face increasing human threats
Must manage as living system to sustain the
physical resource
Must manage groundwater as a living system
Life-supporting capacity
Water qualityAquifer yield
