Managing Smallholder Groundwater-dependent Agrarian Socio-ecologies using an Ecosystem Service and Resilience

Managing Smallholder
Groundwater-dependent Agrarian
Socio-ecologies using an
Ecosystem Service and Resilience
Based Approach
Karen G. Villholth
04 - 07 Nov, 2014
WLE ESS&R Workshop Series
IWMI, Colombo, Sri Lanka
Workshop Objectives
Groundwater and
Ecosystem Service and
Resilience Framework that
supports and facilitates equitable,
efficient and sustainable
benefits from groundwater in
smallholder agrarian systems
• To develop a
Workshop Objectives
• Answer the following questions:
– How can an ESS&R approach help inform and support better
management of GW and the benefits derived from it?
– What is it that we know/don’t know about GW-based ESSs, and interlinkages between GW and ESS?
– What are the trade-offs/synergies and critical thresholds for resilience of
GW-based ESS and agrarian societies reliant on them (GDASEs)?
– What are the (ESSs-based) management interventions and policy
measures to enhance sustainable intensification of agrarian GW-based
socio-economies?
• To develop tangible outputs:
–
–
–
–
Framework Document on GW
Network/think tank
Research questions
Entry points for research and policy/institutional influence
Approach
• Interdisciplinary perspectives
• Interactive deliberations
• Facilitated, but flexible process
– Shorter plenary presentations
– Breakout sessions
– Illustrative field trip
• Output-oriented
Sessions
1. The GW resource
2. The ES and ESS linked to GW
3. The agrarian systems dependent on
GW-derived ESSs
4. Some technical measures to enhance
resilience and sustainability
5. The options for management
What are we trying to achieve?
Agriculture is the largest GW user
globally
22%
1
2
67%
3
11%
van der Gun (2012)
43% of global food production is
produced by groundwater irrigation
- of which 32% is from depleting GW
Villholth et al.,
forthcoming
In India, China, Bangladesh and Pakistan
˜one billion households depend on GW for
agriculture
Global GW abstraction
….coincides
with….
Unit: mm/yr in 0.5° * 0.5° grid cells
van der Gun (2012)
……. Global GW irrigation intensity
Siebert et al. (2010)
…. and limited renewability of GW
GW is often the only alternative for water supply
and irrigation in arid and semi-arid areas
(rain< 500 mm/year)
GW development is unprecedented
Shah et al.,
2007
.... due to development of technology
From the dug well to
the deep borehole
From the waterwheel to the
submersible pump
From the water witches to
hydrogeology
GW has
alleviated
poverty in
India and
elsewhere
m3/person/10,000
Punjab
Haryana
Tamil Nadu
Gujarat
Moench,
2003
Moench,
Moench,2003
2003
Blessing …….
….. and a curse
The
hidden
drought
300 m !
GW foot prints are huge
Poor farmers are hit the worst
Mukherji and Shah, 2003
Mukherji et al., 2003
GW irrigation intensity varies globally
GW irrigated/cultivated land
Siebert et al, 2010
Africa ~1 %
Asia ~14 %
Drivers
• Groundwater provides a reliable and suitable
irrigation source for smallholders:
–
–
–
–
–
–
Ubiquity
In-built distribution and storage
Better water control
All-year irrigation (and income)
Drought resilience
Individual access and management
• Increasing market demand for horticulture crops
• Better (and better access to) low-cost pumps and
wells
• Increasing attention from governments and donors
Reasons why GW mgt. is complex
•
•
•
•
•
GW is a common pool resource
GW is invisible
GW impacts are slow in manifesting
Once manifested, difficult to reverse
Link between cause and effect not obvious
Sustainable level of
resource development
with acceptable impacts
under present conditions
Number of wells
Total abstraction
India, China,
Mexico
USA?
SSA
time
0
1
2
3
4
Baseline
situation
Incipient stress
an
Significant
stress
Unsustainable
development
Sustainable
development
Availability and
accessibility of
adequate quality
groundwater
greatly exceeds
small dispersed
demand
Growth of aquifer
pumping, but only
few local conflicts
between
neighboring
abstractors
Abstraction
expanding rapidly
with impacts on
natural regime
and strong
dependence of
stakeholders on
resource
Excessive
abstraction with
irreversible aquifer
deterioration and
stakeholder
conflicts
High-level of
abstraction, but
sound balance
between
stakeholder
interests and
ecosystem needs
Registration of
wells required,
together with
maps of
occurrence of
usable resources
Simple
management tools
(e.g. appropriate
well-spacing
according to
aquifer properties)
Regulatory
framework
needed, based on
comprehensive
assessment
Regulatory
framework with
demand
management
and/or artificial
recharge urgently
needed
Integrated
management with
high-level of user
self-regulation,
aquifer modeling
and monitoring
WWDR,
2009
WWDR,
2012
Four Categories of Ecosystem Services
Provisioning
Services
Products obtained
directly from ecosystems
•Food
•Fresh water
•Fuel
•Wood, Fiber, Medicine
Photo: Tracy Baker, IWMI
Regulating
Services
Benefits obtained by
regulating ecosystem
processes
•Climate regulation
•Flood regulation
•Disease regulation
•Water purification
Photo: Matthew McCartney, IWMI
Cultural
Services
Material and nonmaterial ecosystems
benefits
•Aesthetic
•Spiritual
•Educational
•Recreational
Photo: Joseph King, TAMUS
Supporting Services
Services necessary for the production of all other ecosystem services:
Soil Formation
Nutrient Cycling
Primary production
MEA 2006
What’s New?
• Water supply = ES provisioning service!
• ESS&R framework, new name for old
ideas of environmental protection but
takes into account the socio-economics
• GW increasingly acknowledged
• Not applied to GDASEs (Groundwaterdependent Agrarian Socio-ecologies)
GW-associated ESSs
• GW underpins most ESs and ESSs:
– Wetlands, springs, riparian areas, coastal and
estuarine zones, terrestrial vegetation, low
flow river systems, aquifer and cave
ecosystems
– Value associated with these systems is huge
– GW not just providing drinking water and
freshwater for other human uses
GW-dependant ESs (GDEs)
1. Ecosystems
dependant on the
surface expression of
groundwater, for
example springs,
streams, and wetlands
2. Ecosystems
dependent on the
subsurface presence
of GW, for example
where vegetation has
roots accessing GW
3. Ecosystems within
aquifers
Progression in understanding
• GW is part of the hydrological cycle!
• GW and SW are linked
• Many surface water bodies are GWdependent
• ESSs are broader than GDEs
• The GW system is itself an ES and
provides significant services and is
vulnerable to changes
GW and ESSs
Discharge
Recharge
Lake
Wetland
River
Spring
Ocean/estuary
Land use
Climate (change)
Waste handling
Flood regulation
Erosion regulation
Soil formation
Phreatophyte
ESSs:
Storage and retention
Biodiversity
WQ modification/pollution control
Nutrient cycling
Sub-surface stability
Temperature regulation
Scales and various systems
Mapping of ESSs
Pagella &
Sinclair,
2014
Quick limits to GW use
Sustainable intensification
Sustainable intensification
UNEP,
2011
Sustainable intensification
….Path C
UNEP,
2011
Effect of deforestation
• Can increase or decrease recharge:
– Decrease recharge, if soil becomes more
crusted and impermeable
– Increase recharge, if new vegetation cover
transpired less water
Managing what?
•
•
•
•
•
ESs?
ESSs?
GW?
Managing trade-offs?
People interacting with ESs and GW?
We have to
turn this…
…into this
Multi-ism
•
•
•
•
Multiple resources
Multi-scales
Multi-purposes
Multi-stakeholders
Thank you!
Contact:
Karen Villholth
k.villholth@cgiar.org