Climate Change, Hydrology, and Landscapes of America’s ... · 1) Landscapes that yield high or...

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Climate Change, Hydrology, and Landscapes of America’s Heartland

NSF Coupled Natural

and Human SystemsPI- Lant

co-PI Schoof,Secchi

Misgna,Nicklow

Virtual Watershed: NSF Biocomplexity in the Environment Program 2004-2008

Key researchers:Christopher Lant (Geography) PISteven Kraft, (Agr. Economics)John Nicklow (Civil Engineering)Girmay Misgna (GIS Lab)George Malanson (Geography) IowaDissertations by: Elias Bekele, Seth Soman, Vineet Yadev

The Modeling Approach

Corn

Other crops

Pasture

Wheat

Soybean

Forest

Urban

Water

Land Use is the Lynchpin Between Social Factors and Environmental Results

Corn

Pasture

SoybeansForest

1999 Landuse Polygon Classification

2000 Landuse Polygon Classification

2001 Landuse Polygon Classification

2002 Landuse Polygon Classification

2003 Landuse Polygon Classification

2004 Landuse Polygon Classification

(1) The use chosen for a field is influenced by the physical geographic characteristics of the field such as soil type and slope. (Yes)

(2) The use chosen for a field is influenced by economic costs and opportunities for various uses. (Yes)

(3) The use chosen for a field is influenced by the use of neighboring fields. (No)

(4) The use chosen for a field is influenced by the historical use of that field. (Yes)

Land Use Change Hypotheses

Probability that a hectare will containUse last Year Corn Soy Double Grass Forest TotalAll Corn .07 .81 .01 .11 .00 1.00

All Soybeans .48 .34 .01 .17 .00 1.00

Double Crop .03 .24 .02 .72 .00 1.00

Pasture/Hay .02 .07 .01 .89 .00 1.00

Forest .00 .00 .00 .00 1.00 1.00

Contingent probabilities of land use in a field given land uses in the previous year

Agent-BasedModeling

Multiple Agents Predict Land Use Decisions Well

Modeling using SWAT

also provides spatial

information on

profitability, soil loss, and

carbon

Ecological-EconomicProduction PossibilityFrontiers and their Evolution

Corn vs. Soybeans: A Classic Trade-off

Corn and Water Quality: A Trade-Off

R = -0.83

Carbon and Corn: A Trade-Off

Hay and Water Quality: Complementary

R = 0.90

Carbon and Hay: Complementary

Carbon and Water Quality: Complementary

R = 0.83

The Overall Ecological-Economic Production Possibilities Frontier

R = -0.83

What We’ve Learned About the PPF1) Landscapes that yield high or low sediment yields also yield

corresponding N and P yields with correlations of 0.93 - 0.98.

2) Competition among crops for land produces as classic PPF

3) Soybeans, and especially corn, is a trade-off with all ecosystem services, but hay is complementary.

4) Carbon correlates positively with water quality at 0.83.

5) The current land use pattern is very sub-optimal, more so with respect to ecosystem services than gross margin. See Tragedy of Ecosystem Services paper and Law and Policy of Ecosystem Services book with Ruhl and Kraft

http:/vws.erp.siu.edu:90/vws/

What about climate change?

Local climates can be downscaled statistically from OAGCMs

Climate Change, Hydrology, and Landscapes of

America’s Heartland

NSF Coupled Natural and

Human SystemsPI- Lant

co-PI Schoof,Secchi

Misgna,Nicklow

And what about multiple watersheds?

Modeling Framework

Agent-Based Modeling

•Profit maximization•Risk aversion•Forward or backward-looking•Labor minimization•Conservation•Distribution

Research Questions and Hypotheses

Research Question 1How are rural land use patterns in the American Heartland study area determined by physical factors such as climate, soil fertility, and slope, socioeconomic factors such as policies and agricultural prices, and geographic factors such as prior and neighboring land uses? How will 21st Century climate change affect these land use patterns at various scales, from macroscale USDA Farm Resource and Land Resource Regions to mesoscale watersheds, to individual farms and fields? How will this change the geography of agricultural production?

What do we expect to

find?

Research Question 2How will (a) agricultural prices, (b) available crops and management techniques, (c) agricultural policies, and (d) policies designed to ameliorate climate change, affect these same 21st Century land use patterns?

Hypothesis 2As agricultural prices rise in response to supply-demand relationships, crop production expands at the margin onto steeper, less fertile, and less humid lands at the expense of pasture and rangeland, which in turn expand along the forest margin. Biofuel production and energy crops such as switch grass accelerate this process. However, falling agricultural prices or policies that reward ecosystem service provision (e.g., carbon storage) have the reverse effect on landscapes, expanding forests (where moisture is sufficient) onto pastures and pastures onto marginal croplands.

Research Question 3As geographically-defined units of natural capital, watersheds are capable of generating sets of both provisioning services (food, fiber, and fuel production) and less often marketed cultural (e.g., aesthetics, recreation) and regulatory (e.g., climate and hydrologic regulation,

water quality) ecosystem services. Will climate change expand or diminish the agricultural production and ecosystem service generation capacities of mesoscale watersheds representative of Farm Resource Regions?

Questions? Comments?