Upload
others
View
8
Download
0
Embed Size (px)
Citation preview
Modelling land use and land cover change with GIS and remote sensing
– what do we miss?
Richard AspinallMacaulay Institute
Outline
• Importance of land use and land cover change
• Drivers of change• Use of GIS and Remote Sensing
– Examples• What is missing?
– Examples• Conclusion
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
Importance of land change
• 50% of ice-free surface has been transformed by human action
• Since 1850, roughly 35% of anthropogenic CO2 emissions have resulted directly from land use activities
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
Importance of land change
• Human activities now appropriate about 25% of the total global primary production (NPP): 53% by harvest40% by land-use-induced productivity changes7% by human-induced fires
Helmut Haberl, K. Heinz Erb, Fridolin Krausmann, Veronika Gaube, AlberteBondeau, Christoph Plutzar, Simone Gingrich, Wolfgang Lucht,
and Marina Fischer-Kowalski www.pnas.org/cgidoi10.1073/pnas.0704243104
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
Human appropriationof net primary production
Helmut Haberl, K. Heinz Erb, Fridolin Krausmann, Veronika Gaube, AlberteBondeau, Christoph Plutzar, Simone Gingrich, Wolfgang Lucht,
and Marina Fischer-Kowalski www.pnas.org/cgidoi10.1073/pnas.0704243104
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
Agriculture:croplands, pastures and rangelands
• Supports over 6 billion people with food, fibre, etc
• Occupies 40% of global land surface– Cropland: 15.1 million km2
– Pasture: 28.3 million km2 (2000 estimate)• 3.3 billion ruminants graze grasslands
(producing methane)
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
Foley et al Science 2005
Agriculture andFood production
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
Agriculture:Food production
• World grain harvests have doubled in the past four decades to >2 billion tons yr-1
– ~12% increase in (world) cropland area– Green Revolution technologies:
• high-yielding cultivars• chemical fertilizers and pesticides• mechanization and irrigation
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
• During the past 40 years, there has been a~700% increase in global fertilizer use~70% increase in irrigated cropland area
• Agriculture has become the largest source of excess N and P to waterways and coastal zones– surpasses natural ecosystems as principal
source of N emissions– leads to degradation of water quality in many
regions
Agriculture:Consequences of land management change
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
• Urban expansion estimated to consume 1-2 million ha yr-1 of cropland in developing world
• Salinity in irrigated lands is associated with a worldwide loss of ~1.5 million ha yr-1 of arable land (est. $11 billion in production)
• Up to ~40% of global croplands (~ 6 billion ha) may be experiencing some degree of soil erosion, reduced fertility, or overgrazing
Agriculture:land use change
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
Water use
• Global water withdrawals now total ~3900 km3
yr-1, or ~10% of the total global renewable resource
• Consumptive use of water estimated at ~1800 to 2300 km3 yr-1
• Agriculture accounts for nearly 85% of consumptive water use globally
• The extraction of groundwater reserves is almost universally unsustainable and has resulted in declining water tables in many regions
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
How much land?• Currently
– 6 x 109 people– 1.5 x 109 ha of cropland– 2500m2 per person (50x50 m)
• By 2050– 9.2 x 109 people (UN median
projection)– 1.25 x 109 ha (assumes 0.4%
loss p.a.)– 1367m2 per person: 37x37m
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
Outline
• Importance of land use and land cover change
• Drivers of change• Use of GIS and Remote Sensing
– Examples• What is missing?
– Examples• Conclusion
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
Geist, H. J. and Lambin, E. F. (2001) What drives tropical deforestation? A meta-analysis fo proximate and underlying causes of deforestation based on subnational case study evidence. LUCC Report Series no. 4.
Drivers of change…
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
UNDERLYING CAUSES
CONSTRAINTS ON CHOICE
PROXIMATE CAUSES
CONSEQUENCES
Modified from: Geist and Lambin(2002);Birnie et al., (2002)
Land Quality/Suitability
Land Tenure
Social Norms
IndividualPreferences
Finance
Economic
Social
Environmental
External Factors/Trigger Eventse.g. weather, economic shocks
Cultural
Policy and Institutional
Demographic
Economic
Technological
Environmental
Agricultural ChangesCultivation techniquesRanching….
Infrastructure ChangesTransportationMarkets, AgreementsServices
Industrial ChangesEmploymentIndustry…
Drivers of change
Outline
• Importance of land use and land cover change
• Drivers of change• Use of GIS and Remote Sensing
– Examples• What is missing?
– Examples• Conclusion
Snapshots
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
Snapshots
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
Snapshots1946 1988
Land cover change – Cairngorms, Scotland.Source: Land Cover of Scotland 1988 and Land Cover of Scotland ‘Lookback’ studies(Macaulay Institute)
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
Snapshots: Panel analysisThe panel process, conducted at both the pixel and patch
levels: 1. four multispectral satellite images are each categorized
into a thematic LULC classification;2. pattern metrics are run on each of the four LULC
classifications, each producing a set of patch, class, and landscape statistics (here the Interspersion / Juxtaposition Index or IJI and Mean Patch Size or MPS are shown) as well as an output image of the delineated patches;
a. pattern metric output for each of the four times is used to calculate three piecemeal change maps for each pattern metric and each consecutive pair of images (e.g., showing fluctuations in IJI or MPS between two time periods)
b. three pattern change maps are stacked into one panel of all structural change for each given metric (e.g., showing fluctuation in IJI or MPS through all time periods)
3. three thematic change maps are created for each of the time periods represented by the four classifications;
a. the three thematic change maps are stacked to represent the full record of all thematic change across the four classifications
Kelley Crews, University of Texas at Austin
1
2
3
2a
2b3a
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
Stylized trends for land use/land coverchange in Northeast Thailand 1970 to late 1990s
Change in land type Change in pattern metrics
1970 2000 1970 2000
1970 2000Kel
ley
Cre
ws,
Uni
vers
ity o
f Tex
as a
t Aus
tin
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
Outline
• Importance of land use and land cover change
• Drivers of change• Use of GIS and Remote Sensing
– Examples• What is missing?
– Examples • Conclusion
What is missing?
1. What might we miss with snapshots (especially if based on land cover)?
2. What is missing from our understanding of the mechanisms of change (the processes of change behind the drivers)?
3. What aspects of land use and land cover might we investigate further with GIS and Remote Sensing?
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
What is missing?
1. What might we miss with snapshots (especially if based on land cover)?
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
Agricultural Census
• Agricultural (June) census:national, regional andlocal statistics
• Collected since 1866• Data converted to
metric units– Production: metric tons– Yield: metric tons/ha– Area: hectares
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
Areas of major agriculturalland types in Scotland 1900-2006
Are
a (h
a)
0
1,000,000
2,000,000
3,000,000
4,000,000
5,000,000
6,000,000
7,000,000
8,000,000
1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010
Arable Land Rotation Grass Permanent Grass Rough Grazings
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
ARABLE - 1988ARABLE - 1931
Land Cover ofScotland 1988
First Land Utilisation Survey of GB
Hectares4,340,5803,843,385
Arable agriculture: Scotland
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
Areas of major agriculturalland types in Scotland 1900-2006
Are
a (h
a)
0
1,000,000
2,000,000
3,000,000
4,000,000
5,000,000
6,000,000
7,000,000
8,000,000
1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010
Arable Land Rotation Grass Permanent Grass Rough Grazings
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
1922192319241925192619271928192919301931193219331934193519361937
No. of timesyrt <> yrt-1
nmax = 15
4 - 7
8-11
11-15
sprin
g sow
n crop
(barl
ey, o
ats)
autum
n sow
n grai
n (whe
at)
rotati
on gr
ass,
clove
r
root c
rop (tu
rnip,
potat
oes)
perm
anen
t gras
s
1922
1937
The Wicken, Castle Acre,Norfolk
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
L. Dudley Stamp (1948) The Land of Britain, It’s use and misuse. Longmans, Green and Co. Ltd with Geographical Publications Ltd.
After: The Land of Britain: The Report of the Land Utilisation Survey of Britain. Part 70, Report on Norfolk by Mosby, J. E. G. (1938)
Crop rotation
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
The Wicken, Castle AcreNorfolk
2007
Source: GoogleEarth
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
Snaphots to model change
Need to consider spatial units (eg farm, parcel – not pixel)
192219231924192519261927 1928 1929 1930
1931 1932 1933 1934
1935 1936 1937
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
Major land uses and animal numbers in Scotland
Are
a (h
a)
0
4,000,000
8,000,000
12,000,000
1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010
0
1,000,000
2,000,000
3,000,000
4,000,000
5,000,000
6,000,000
7,000,000
8,000,000
1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010
Arable Land Rotation Grass Permanent Grass Rough Grazings
Cattle
Sheep
coun
t
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
What is missing?
1. What might we miss with snapshots (especially if based on land cover)?
2. What is missing from our understanding of the mechanisms of change (the processes of change behind the drivers)?
• Technological• Structural (policy)• Cultural/Social• Economic
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
1. Technological change
• Crop breeding and yield/production• Mechanisation of agriculture
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
1860 1870 1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 20100
2
4
6
8 Barley
1860 1870 1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010012456 Oats
1860 1870 1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 201002468
10 Wheat
t/ha
t/ha
t/ha
Crop breeding:increased yield
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
1860 1870 1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 20100
50,000
100,000
150,000
200,000
250,000Horses for Agricultural Use
1860 1870 1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010Year
0
20000
40000
60000
80000Combines + Tractors
Mechanisation of agriculture
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
Technological change
• Technological innovation• Diffusion and adoption of technology
• Not a change in use or cover, but has considerable importance (for natural and human systems)
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
1800 1810 1820 1830 1840 1850 1860 1870 1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010Year
0
200,000
400,000
600,000
800,000
1,000,000Oats.tonnes
1800 1810 1820 1830 1840 1850 1860 1870 1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 20100
50,000
100,000
150,000
200,000
250,000
Horses for Agricultural Use
Associated consequences
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
2. Structural (Policy) change
• Common Agricultural Policy – price support– overproduction in 1980s– Set aside (EU) – 1988 onwards– LFA Payments– High Nature Value areas– CAP Reform– …
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
1860 1870 1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 20100
40000
80000
120000
160000
Whe
at.h
a
Area sown toWheat, Scotland
Common Agricultural Policy:Price Support
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
1860 1870 1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010Year
0
30000
60000
90000
120000
Seta
side
+ B
areF
allo
w.h
a Bare Fallow + Set aside, Scotland
Common Agricultural Policy:Set aside
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
Structural (Policy) change
• Policy creation: decision-making• Adoption: decision-making
(even, in some places, where this required a massive change in farming practice, for example from grazing to arable)
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
3. Cultural/Social change
• amenity and lifestyles– Rocky Mountains in the US have seen
explosive growth in number of people and in housing
– Change linked to lifestyle and amenity preferences
–(demographic and cultural change)
Example: Gallatin County, Montana, USA
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
Gallatin County: New HomesGallatin County Population 1890-2000
14079 15864 16124 18269 21902 2604532505
42865
6246 9553
50463
67831
020000400006000080000
Trouper Trail from Triple Tree Ranch Subdivision
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
Properties
Pre-1890
Early Settlement
1890-1934
Rapid Settlement
1935-1966
Adjustment
1967-1984
Resource reallocation
1985-2000
Resource reallocation
well and septic permit records (1860-2000)- Locations of properties
- Date
Site: WaterWoodlandSlope
Amenity: Proximity to National ForestView from property - Visibility
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
Proximity to National Forest Visibility
Amenity
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
Models for different times
Model Pre-1890 1890-1934 1935-1966 1967-1984 1985-2000
Variables
Period
BozemanSlopeWaterForest
RailroadSlopeWaterForest
TownsSlopeWaterForest
BozemanSlopeNat Forest
BozemanSlopeNat ForestVisibility
Pre-1890 0.521 0.126 0.098 0.184 0.071
1890-1934 0.000 1.000 0.000 0.000 0.000
1935-1966 1.000 0.000 0.000 0.000 0.000
1967-1984 0.000 0.000 0.000 0.691 0.309
1985-2000 0.000 0.000 0.000 0.331 0.668
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
Gallatin County, Montana
• Amenity is a relatively recent influence on change
• Processes: reflects choices and decisions based on values, attitudes, and beliefs as well as economics and finance
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
4. Economic change• Globalization• World markets• Change in relative price and demand for fuel and food• …
US Maize production for ethanol:2006-7: 2 billion bushels out of 12 million bushels (16.6%)2007-8: forecast to rise to 3.5 billion bushels (35%)
70 new ethanol plants are under construction – this will double the amount of maize consumed for fuel (Autumn 2007 data)
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
Processes producing change
• Technological change– Innovation, diffusion
• Structural, Cultural, Economic– Decision-making, regulation
• Decisions and choices– Based on knowledge, values, attitudes,
beliefs, preferences, …
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
Decision making
www.globallandproject.org
Land-coverBiophysical control
Land-useHuman control
EcologicalSystems
BiogeochemistryBiodiversity
WaterAir, Soil
SocialSystemsPopulation
Social/Economic structurePolitical/institution regime
Culture, Technology
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
What is missing?
1. What might we miss with snapshots (especially if based on land cover)?
2. What is missing from our understanding of the mechanisms of change (the processes of change behind the drivers)?
3. What aspects of land use and land cover might we investigate further (with GIS and Remote Sensing)?
Animalsand animal husbandry
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
Animal husbandry
0
4,000,000
8,000,000
12,000,000
1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010
Cattle
Sheep
coun
t
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
1860 1870 1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010Year
0
2,000,000
4,000,000
6,000,000
8,000,000
10,000,000Sheep
1860 1870 1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 20100
500,000
1,000,000
1,500,000
2,000,000
2,500,000
3,000,000
Cattle
Animal numbers
Cattle
Sheep
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
1860 1870 1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010Year
0
200,000
400,000
600,000
800,000
1,000,000Pigs
1860 1870 1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 20100
5,000,000
10,000,000
15,000,000
20,000,000
Poultry
Poultry
Pigs
Animal numbers
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
Nitrogen:Cattle, horse, sheep manure, inorganic fertilizer
1860 1870 1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990Year
0
50000000
100000000
150000000
200000000
250000000
300000000
N (k
g)
Inorganic fertilizer – barley, oats, wheat
Cattle, horse, sheep manure
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
Major land uses and animal numbers in Scotland
Are
a (h
a)
0
4,000,000
8,000,000
12,000,000
1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010
0
1,000,000
2,000,000
3,000,000
4,000,000
5,000,000
6,000,000
7,000,000
8,000,000
1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010
Arable Land Rotation Grass Permanent Grass Rough Grazings
Cattle
Sheep
coun
t
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
Land management
Changes in, and types of, land management are important, especially in relation to land function (e.g. provision of ecosystem services)
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
Land management
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions
Conclusions
1. Influence of processes, rather than drivers, of change
• Decisions2. Land (use) systems:
e.g. agriculture• Animal Systems and Husbandry• Land Management practices
3. Land ‘functions’ – how land systems work, what they do: ecological (environmental) goods and services
Outline Land managementImportance Drivers of change GIS use What is missing? Drivers Animals Conclusions