A presentation by Prof. David Bignell: Towards a universal sampling protocol for macro and meso-fauna in the humid tropics

1. 5/27/2010
1. Premises for our Project
ASB and CSM-BGBD: towards a 2. Why fauna?
universal sampling protocol for
soil biotas in the humid tropics 3.
3 Evolution of sampling methods
4. (Evolution of sampling design)
David Bignell
Queen Mary, University of London, UK 5. Conclusions
and
Universiti Malaysia Sabah, Kota Kinabalu, Malaysia
Does soil biodiversity matter?
IN MEMORIUM
Anggoro Hadi Prasetyo
The Indonesian Institute of
Sciences
1970 - 2010
Key international research and development aid projects address the
issue of declining soil fertility. The questions asked are:
• 3. Are there alternative
land uses which sustain
agricultural productivity
• 1. What is the relationship
and retain high
between AG and BG
biodiversity?
biodiversity across
current and alternative
land use systems?
• 4. Is agricultural
• 2. Can management production at forest
interventions in existing margins made
practices improve soil sustainable and improved
biodiversity? by enhancement of soil
biodiversity?
1

2. 5/27/2010
• Sampling as hypothesis-testing: • Sampling as hypothesis-testing:
• BGBD expected to follow gradients of disturbance or land use
• BGBD expected to follow gradients of disturbance or agricultural intensity or SOM. The central hypothesis is that variation in BGBD is
intensification or loss of SOM. The central hypothesis is that associated with land use intensity described at the level of major
variation in BGBD is associated with land use intensity described at land use categories.
the level of major land use categories. • Usually carried out by cross-sectional studies (gradsects if land uses
are aligned to one environmental variable, usually land use
• Usually carried out by cross-sectional studies (gradsects if land uses intensity), as experimental and longitudinal approaches are not
are aligned to one environmental variable, usually land use feasible.
feasible
intensity), as experimental and longitudinal approaches are not
feasible. • Sampling without a priori hypotheses
• Find the environmental variables which best explain the observed
patterns of BGBD
• But which variables do you measure, and what happens if they
correlate with each other?
2

3. 5/27/2010
What is the future of tropical landscapes?
• Some primary and secondary forests gazetted as reserves, but
mainly at higher altitudes, including montane forests.
Biodiversity retention up to 100%
• Plantation landscapes: rubber, oil palm, pulpwood, hardwood.
Biodiversity retention variable 10% - 50%
• Segregated landscapes: intact larger or smaller forest
fragments separated by crop or plantation monocultures,
mixtures or rotations. Notable edge effects. Biodiversity
retention up to 60%
• Integrated landscapes: multistrata mixed treecrops or
agroforests. Biodiversity retention 40%
• Uniformly simplified or degraded landscapes: nutrient depleted
sites dominated by invasive weeds, with severe soil erosion.
Biodiversity retention 10% or less
3

4. 5/27/2010
Ecosystem function conservation is a more practical approach than biodiversity Ecosystem function conservation is a more practical approach than biodiversity
conservation per se; for example the following 10 functional groups are required: conservation per se; for example the following 10 functional groups are required:
• 1. Primary producers (higher and lower • 6. Predators (many macrofauna and • 1. Primary producers (higher and lower • 6. Predators (many macrofauna and
plants): photosynthetic organisms mesofauna): animals which regulate plants): photosynthetic organisms mesofauna): animals which regulate
assimilating carbon dioxide from the air, herbivores, ecosystem engineers, litter assimilating carbon dioxide from the air, herbivores, ecosystem engineers, litter
penetrating the soil with rooting systems and transformers, decomposers and penetrating the soil with rooting systems and transformers, decomposers and
translocating organic compounds microregulators through predation. translocating organic compounds microregulators through predation.
synthesized above ground. • 7. Microregulators (e.g. microfauna such synthesized above ground. • 7. Microregulators (e.g. microfauna such
• 2. Herbivores: animals consuming and as nematodes): animals which regulate • 2. Herbivores: animals consuming and as nematodes): animals which regulate
partly digesting living plant tissues, including nutrient cycles through grazing and other partly digesting living plant tissues, including nutrient cycles through grazing and other
leaf miners and rollers, stem borers and sap interactions with the decomposer leaf miners and rollers, stem borers and sap interactions with the decomposer
suckers. microorganisms. suckers. microorganisms.
• 3. Ecosystem engineers (e.g. macrofauna • 8. Microsymbionts (e.g. mycorrhizal fungi, • 3. Ecosystem engineers (e.g. macrofauna • 8. Microsymbionts (e.g. mycorrhizal fungi,
such as termites, earthworms):organisms rhizobia): microorganisms associated with such as termites, earthworms):organisms rhizobia): microorganisms associated with
which have major physical impact on soil roots that enhance nutrient uptake which have major physical impact on soil roots that enhance nutrient uptake
through soil t
th h il transport ,building of aggregate
t b ildi f t • 9. Soil-borne pests and diseases (e.g. through soil t
th h il transport, b ildi of aggregate
t building f t • 9. Soil-borne pests and diseases (e.g.
structures and formation of pores – as well fungal pathogens, invertebrate structures and formation of pores – as well fungal pathogens, invertebrate
as influencing nutrient cycling. Can include pests):biological control species (e.g. as influencing nutrient cycling. Can include pests):biological control species (e.g.
predators (e.g. many ants). predators, parasitoids and hyper parasites of predators (e.g. many ants). predators, parasitoids and hyper parasites of
• 4. Litter transformers (many macrofauna pests and diseases) can also be included. • 4. Litter transformers (many macrofauna pests and diseases) can also be included.
and mesofauna, but some microfauna): • 10. Prokaryotic transformers: Archaea and and mesofauna, but some microfauna): • 10. Prokaryotic transformers: Archaea and
invertebrates feeding on microbially- Bacteria performing specific transformations invertebrates feeding on microbially- Bacteria performing specific transformations
conditioned organic detritus and shredding of carbon (e.g.methanotrophy) or nutrient conditioned organic detritus and shredding of carbon (e.g.methanotrophy) or nutrient
this material (comminution) and making it elements such as N, S or P (e.g. nitrification, this material (comminution) and making it elements such as N, S or P (e.g. nitrification,
more accessible to decomposers, or nitrogen fixation). more accessible to decomposers, or nitrogen fixation).
promoting microbial growth in pelletized promoting microbial growth in pelletized
faeces. This activity can be performed at • Source: Swift, M.J., Bignell, D.E., Moreira, F.M.S., Huising,
faeces. This activity can be performed at • Source: Swift, M.J., Bignell, D.E., Moreira, F.M.S., Huising,
several spatial scales. E.J. 2008. The inventory of soil biological diversity: concepts several spatial scales. E.J. 2008. The inventory of soil biological diversity: concepts
• 5. Decomposers (e.g. cellulose degrading and general guidelines. In: A Handbook of Tropical Soil • 5. Decomposers (e.g. cellulose degrading and general guidelines. In: A Handbook of Tropical Soil
Biology: Sampling and Characterization of Below-ground Biology: Sampling and Characterization of Below-ground
fungi or bacteria): microorganisms Biodiversity (eds. F.M.S. Moreira, E.J. Huising and D.E. fungi or bacteria): microorganisms Biodiversity (eds. F.M.S. Moreira, E.J. Huising and D.E.
possessing the polymer degrading enzymes Bignell), pp 1-16. Earthscan, London. possessing the polymer degrading enzymes Bignell), pp 1-16. Earthscan, London.
that are responsible for most of the energy that are responsible for most of the energy
flow in the decomposer food web. flow in the decomposer food web.
Where are we now?
• 1989 “TSBF” : Tropical Soil Biology and Fertility
(Anderson and Ingram)
• 2001 ASB: Alternatives to Slash-and-Burn
(
(Swift and Bignell)
g )
• 2008 CSM-BGBD: Conservation and Sustainable
Management of Below-ground Biodiversity
(Moreira, Huising and Bignell)
4

5. 5/27/2010
The “TSBF” transect (1989)
25 cm 5 metres
5, 8 or 10
25 monoliths as
cm resources
permitit
20 or 30 cm
depth
40 metres Other cores (pattern not specified) for:
Mycorrhizal roots
Rhizosphere bacteria
Viable rhizobia
Macrofauna Soil physics/chemistry
The Swift and Bignell ASB transect (2001)
60
20 small cores
Prior litter removal, then per 8 x 5 m
5-8 soil monoliths, each section for
25 x 25 x 30 (depth) cm microsymbionts 50 2500 40
Soil physical
Examine plant sampling
roots for nodules from walls of
and mycorrhiza monolith pit
40 m 40 2000
30
Monolith soil
5m sorted for
for macrofauna
TRANSECT 1
30 1500
Line of 10 (or more) pitfall traps, each 20
ca.15 cm diameter
10 soil samples from plant 20 1000
rhizosphere, 0-30 cm, bulked to
ca. 1 litre for nematode extraction
1 2 3 4 5 6 7 8 9 10 11 etc. 19 20 10
10 500
Qualitative termite transect, 100 x 2 m, in 20 sections of 5 x 2 m each
40 m
0
Pristine Logged Tree Rubber Jungle Alang- Cassava
5m
forest forest plantation plantation rubber alang field
19 20
TRANSECT 2
Land-use system
Termite transect can turn up to 90o
to accommodate topography or
bend around living trees.
CSM-BGBD monolith, ring and transect (2008) CSM-BGBD enhanced monolith and transect (2008)
5

6. 5/27/2010
CSM-BGBD sampling points allocated by a GPS grid
Sampling Sampling scheme
parameter
“TSBF” transect Swift & Bignell CSM-BGBD CSM-BGBD
(1989) (2001) basic alternate (2008)
(2008)
Selection of plots Not specified Subjective From GPS From GPS
window grid window grid
Plots per land use Not specified 3 20 20
recommended
Sampling events Not specified 620 (1860) 51 (1020) 71 (1420)
per plot (per
land use in
bracket)
Samples for Not specified 106 (318) 22 (440) 42 (840)
analysis per plot
(per land use in
bracket)
Time required One day Two days One day Two days
per plot,
assuming 6-10
staff available*
* includes on-site sorting time for monoliths
Sampling parameter Transect based (few Grid based (many
plots, higher effort per plots, lower effort per Conclusions
plot) plot)
Ease of positioning Higher Lower • 1. Selection of sampling points should be grid-
samples, access to sites
and field logistics based. This provides for:
Overall field time Shorter Longer
– the best representation of land uses
Representation of the Less good, normally Better, normally
land use distribution more subjective; derived from remote – the best statistical descriptions of data
concentrates sensing; spreads
sampling, but rare sampling, but rare
land uses can be land uses may be
chosen missed
Autocorrelation High Low
• 2. Plot sampling schemes can combine
Stratification Possible Possible monoliths, transects and soil cores. This
Sensitivity to
aggregated species
Low High (better than
random sampling)
provides for:
Precision of Higher Lower – co-location of sampling for macrofauna, mesofauna,
biodiversity sampling
Replication Pseudoreplication Genuine replication
microfauna, microsymbionts and other microbiota
Redundant points Few, if any Some – the highest resolution of below-ground biodiversity
Estimations of Problematic (or high Possible (or lower
abundance and variance) variance)
biomass
6

7. 5/27/2010
7