Session 5.3
Biodiversity and agroforested
habitats
Ecosystem Functions, Goods and Services
de Groot et al 2002
Habitat provision by trees
• Microclimate buffering
Habitat provision by trees
• Microclimate buffering• Nutrient availability• Water availability• Provision of C substrates• Host for pollinators• Host biological control agents
WaNuLCAS
TREE-BGBD
TREE-AGBDPres. #1,#2,#3
Pres. #4,#5,#6
Habitat provision by trees
Tree-soil interactions and the provision of soil-mediated
ecosystem servicesEdmundo Barrios, Fred Ayuke, Diana H. Wall, Scott Bates,
Noah Fierer, Keith Shepherd
University of Nairobi
GSBIGlobal Soil Biodiversity Initiative
OUTLINE1. Biodiversity management in agricultural landscapes
2. Land health surveillance framework
3. Challenges and opportunities
AGBDAbove-ground: planned, managed biodiversity
BGBDBelow-ground: unplanned, unmanaged biodiversity
BIODIVERSITY MANAGEMENT IN AGRICULTURAL LANDSCAPES
Planned and managed aboveground biodiversity
Diversitas 2005
Unplanned, unmanaged belowground biodiversity
???
Why bother about Soil Biota when considering Ecosystem
Services?
Influencing plant health (pathogens & pests vs. natural predators & parasites)
Primary driving agents of nutrient cycling (C, N, P, S)
Regulators of dynamics of: soil organic matter carbon sequestration greenhouse gas emissions
Modify soil physical structure and water regimes
Enhance amount & efficiency of nutrient acquisition of plants (Symbiosis)
(Barrios 2007)
SOIL BIOLOGICAL FUNCTION AND THE PROVISION OF ECOSYSTEM SERVICES
Barrios et al, 2012
What about trees and soil-based ecosystem services?
Strong linkage between aboveground biodiversity (vegetation/crops) and belowground biodiversity
(soil organisms)
Great potential to strategically utilize land use and management systems to influence
the provision of ecosystem goods and services
AGROFORESTRY Close to half of agricultural land has > 10%Tree cover (Zomer et al 2009)
Agroforestry
Agriculture
RR
References
Soil macrofauna
(indiv m-2)
(indiv m-2)
Earthworms
54.4
17.6
3.1
1,2,3,4,5,6
Beetles
20.9
9.6
2.2
1,2,5
Centipedes
2.7
0.5
5.6
1,2,5
Termites
90.7
81.0
1.1
1,2,5
Ants
23.2
8.6
2.7
1,2,5
Soil mesofauna
(indiv m-2)
(indiv m-2)
Collembola
3890.1
2000.7
1.9
7
Mites
5100.7
1860.1
2.7
7
Soil microfauna
(indiv liter-1)
(indiv liter-1)
Non-parasitic nematodes 2922
1288
2.3
8
Parasitic nematodes
203.7
211.5
1
8
Mean density of different soil biota and calculated response ratios
Some effects of trees are mediated through impact on soil biota – trees increase
abundance
Barrios et al. 2012
Some effects of trees are mediated through impact on soil biota – trees
increase activity
Pruned trees
Free growing trees
Earthworm cast weight
Sample with no earthworm casts
Greater soil biological activity (earthworms) near trees but effect greater for some tree species than others
Pauli et al 2010
TREES AS HOTSPOTS OF BIOLOGICAL ACTIVITYIN AGRICULTURAL LANDSCAPES
Barrios et al. 2012
AfSIS - A Globally Integrated African Soil Information Service (www.africasoils.net)
International Center for Tropical Agriculture (CIAT) Tropical Soil Biology and Fertility Institute (TSBF), Earth Institute at Columbia University, World Agroforestry Centre (ICRAF), International Soil Reference Information Centre (ISRIC)With support from Bill & Melinda Gates Foundation and Alliance for a Green Revolution in Africa (AGRA)
Land Health Surveillance
AfSIS Sentinel Sites
Cluster#4
Cluster#2
Cluster#3
Cluster#1
Cluster#8
Cluster#6
Cluster#7
Cluster#5
Cluster#12
Cluster#10
Cluster#11
Cluster#9
Cluster#16
Cluster#14
Cluster#15
Cluster#13
10 km
10 km
SENTINEL SITE (100 km2)
Subplot #2
Subplot #1
Subplot #3
Subplot #4
Plot 1000 m2
2.5 Km
2.5 Km
CLUSTER (1 km2)
Sub-plots 100 m2
Sampling plot (1000 m2)sub-plots (100 m2)
SOIL BIOTA
LDSF characterization of Woody Cover
T-square method
Tree density, basal area, biovolume and biomass
PLANTS
Tree Density Mapping at Fine Resolution
Map of tree density in an areas with steep climatic gradients in northern Kenya, derived from modeling ground data collected from sentinel sites to Landsat imagery (28.5 m
resolution).
AfSIS Soil Characterization
• High throughput system
• Infrared spectroscopy on all samples
• Reference samples on subsets
Measuring Soil Carbon in Landscapes
1988
2006
Soil samples0-20 cm, 20-50 cmComposited per plot (1000 m2)
Soil macrofauna
Soil DNA analysis (DESS soil)
Soil analysis
25 cm
25 cm
20 c
m
Soil analysis
Soil Biological Properties
One per subplot (100 m2)
Soil DNA analysis (dry soil)
Systematic assessment of Local Ecological Knowledge on tree-soil biota interactions
Soil monoliths
Barrios et al., 2013
Spatial distribution of earthworms across a Sentinel Site Dark circles = presence, light circles = absence
Soil macrofauna distribution
DNA extracted from soil samples
AGCCTTAA…
GCTACCAT…
CGGATCAC…
CTCGATTC…
AGCCTTAA…
GCTACCAT…
CGGATCAC…
CTCGATTC…
AGCCTTAA…
GCTACCAT…
CGGATCAC…
CTCGATTC…
-Pyrosequencing gives ~1500 sequence per sample across many samples (>450,000 seq per run)
- Illumina (MySeq 5 million seqs per run)
-PCR amplification with groupspecific primers for SSU rRNA gene
Pyrosequencing
-Taxonomic Information per sample
-High throughput system
Heat map showing the levels of total % N in soil (left) as well as abundance of DNA sequence types representing Bradyrhizobium (right) at Sentinel Site
Soil total N Bradyrhizobium DNA sequences
CHALLENGES & OPPORTUNITIES
Developing better understanding of AGBD/BGBD interactions
maintain essential ecosystem functions provided by soil biota
in agricultural landscapes.
Recommendations of what types of tree densities, arrangements and species
Identifying, Quantifying and Mapping Host Spots of Biological Activity and
Ecosystem Services
Temporal and spatial dynamics as a result of environmental factors in situ
Predictive knowledge of Ecosystem Service Provision
Developing Local Soil Health Monitoring Systems to evaluate
Ecosystem Service provision performance
Allow rural communities, environmental/agricultural institutions
and local government
Prepare for negotiations related toPayment for Ecosystem Services
Thank you!