Implications of Agricultural Intensification and Climate Change on Water Quality-A Global Assessment

Uniting agriculture and nature for poverty reduction

Hua Xie*, Claudia Ringler and Gauthier Pitois

Implications of Agricultural Intensification and Climate

Change on Water Quality-A Global Assessment

Sustainability in the Water-Energy-Food Nexus

International Food Policy Research InstituteMay 19-20, 2014 in Bonn, Germany

Uniting agriculture and nature for poverty reduction

Outline

Water quantity and water quality- two sides of one coin

Global water quality assessment – an emerging research field

Non-point source agricultural pollution

Uniting agriculture and nature for poverty reduction

Nitrogen and phosphorus in agriculture

Essential elements for life Excess nitrogen and phosphorus in aquatic environment cause

water quality problems

Photo: Wikimedia Commons.

Uniting agriculture and nature for poverty reduction

Methodology

Land model

Transport model

N&P concentrations in water environment

N&P emissions from agricultural production system on land

Hydrologic model

Stream flow

Uniting agriculture and nature for poverty reduction

Methodology Process-based simulation

of nitrogen and phosphorus in agricultural production

Soil and Water Assessment Tool (SWAT)

Spatial resolution: 0.5˚ × 0.5˚ lat/long grid

Uniting agriculture and nature for poverty reduction

Input data-base period (2000-2005)Data SourceTopography HydroSHEDSSoil HWSDPrecipitation GPCPTemperature GEOS-4 & GEOS-5Solar radiation GEWEX SRB 3.0Fertilizer use1 University of Minnesota (Muller et al.,

2012)Cropland area McGill University (Monfreda et al.,

2008) Nitrogen atmospheric deposition

ORNL

1. Simulated crops: maize, wheat, rice, cotton, sorghum, millet, soybean

Uniting agriculture and nature for poverty reduction

Input data-base period (2000-2005)

Uniting agriculture and nature for poverty reduction

Six agricultural intensification pathways

Input data –scenario analysis

Socioeconomic growth Climate change

Optimistic CSIRO (A1B)Medium MIROC (A1B)

Pessimistic

Uniting agriculture and nature for poverty reduction

Input data –scenario analysis (population)

2000 2005 2010 2015 2020 2025 2030 2035 2040 2045 20502

4

6

8

10

12

CSIRO&MIROC-medium CSIRO&MIROC-optimistic CSIRO&MIROC-pessimistic

Popu

latio

n (b

illio

n pe

ople

)

Uniting agriculture and nature for poverty reduction

Input data –scenario analysis (GDP)

2000 2005 2010 2015 2020 2025 2030 2035 2040 2045 20500

40

80

120

160

200

CSIRO&MIROC-medium CSIRO&MIROC-optimistic CSIRO&MIROC-pessimistic

GD

P (b

illio

n U

SD)

Uniting agriculture and nature for poverty reduction

Input data –scenario analysis (cropland)

2000 2005 2010 2015 2020 2025 2030 2035 2040 2045 20501400

1450

1500

1550

1600

1650

1700

1750

1800

CSIRO-medium CSIRO-optimistic CSIRO-pessimisticMIROC-medium MIROC-optimistic MIROC-pessimistic

Crop

ping

are

a (m

illio

n ha

)

Uniting agriculture and nature for poverty reduction

Input data-scenario analysis (livestock)

2000 2005 2010 2015 2020 2025 2030 2035 2040 2045 2050200

250

300

350

400

450

500

CSIRO-medium CSIRO-optimistic CSIRO-pessimisticMIROC-medium MIROC-optimistic MIROC-pessimistic

Tota

l mea

t pro

ducti

on (m

illio

n to

ns/y

r)

Uniting agriculture and nature for poverty reduction

Input data-scenario analysis (NUE)

─ Optimistic scenario: 40% NUE improvement

─ Medium scenario: 20% NUE improvement

─ Pessimistic scenario: no NUE improvement

𝑁𝑢𝑡𝑟𝑖𝑒𝑛𝑡𝑢𝑠𝑒𝑒𝑓𝑓𝑖𝑐𝑖𝑒𝑛𝑐𝑦 (𝑁𝑈𝐸 )= 𝑐𝑟𝑜𝑝 𝑦𝑖𝑒𝑙𝑑(𝑘𝑔)𝑛𝑢𝑡𝑟𝑖𝑒𝑛𝑡 𝑎𝑝𝑝𝑙𝑖𝑒𝑑(𝑘𝑔)

(Partial Productivity Factor, PFP)

Uniting agriculture and nature for poverty reduction

Input data-climate change

CSIRO change in precipitation

Uniting agriculture and nature for poverty reduction

Input data-climate change

CSIRO change in temperature

Uniting agriculture and nature for poverty reduction

Input data-climate change

MIROC change in precipitation

Uniting agriculture and nature for poverty reduction

Input data-climate change

MIROC change in temperature

Uniting agriculture and nature for poverty reduction

Input data-climate change CNRM-CM3 model with A1B scenario for 2050CNRM-CM3 model with A2 scenario for 2050CNRM-CM3 model with B1 scenario for 2050CSIRO-Mk3.0 model with A1B scenario for 2050CSIRO-Mk3.0 model with A2 scenario for 2050CSIRO-Mk3.0 model with B1 scenario for 2050ECHam5 model with A1B scenario for 2050ECHam5 model with A2 scenario for 2050ECHam5 model with B1 scenario for 2050MIROC 3.2 (medium resolution) model with A1B scenario for 2050MIROC 3.2 (medium resolution) model with A2 scenario for 2050MIROC 3.2 (medium resolution) model with B1 scenario for 2050

(Jones et al., 2009)

Uniting agriculture and nature for poverty reduction

Nitrogen loading-base period

46 million tons/yr

Uniting agriculture and nature for poverty reduction

Phosphorus loading-base period

2.7 million tons/yr

Uniting agriculture and nature for poverty reduction

Nitrogen loading-2050

Baselin

e

CSIRO_optimistic

CSIRO_medium

CSIRO_pessimisti

c

MIROC_optimisti

c

MIROC_medium

MIROC_pessi

mistic

0

10

20

30

40

50

60

70

80

90

46

6268

7368

7481

Mill

ion

tons

/yr

Uniting agriculture and nature for poverty reduction

Phosphorus loading-2050

Baselin

e

CSIRO_optimistic

CSIRO_medium

CSIRO_pessimisti

c

MIROC_optimisti

c

MIROC_medium

MIROC_pessi

mistic

0

0.5

1

1.5

2

2.5

3

3.5

4

2.7 2.8 2.9 3.0 3.13.3 3.4

Mill

ion

tons

/yr

Uniting agriculture and nature for poverty reduction

Nitrogen loading growth rate by country

Uniting agriculture and nature for poverty reduction

Phosphorus loading growth rate by country

Uniting agriculture and nature for poverty reduction

Key messages

The outlook is alarming—large additional N and P emissions from agriculture projected by 2050

What can be done

─ better fertilizer policy and knowledge of fertilizer use

─ land conservation

─ Manure management

Uniting agriculture and nature for poverty reduction

Acknowledgement

This study is supported by Veolia North America under the CGIAR Research Program on Water, Land and Ecosystems (WLE)

Thank you！