Consequences of Institutional Change: Land-Cover Dynamics in Kazakhstan 1960-2000
Anatoly Gitelson, Geoffrey Henebry (Principal Investigators), University of Nebraska
This project explores the biogeophysical consequences of the collapse of the Soviet Union in the early 1990s, with a particular emphasis on Kazakhstan, the second largest country to emerge from the Soviet Union (after Russia) and the ninth largest country on the planet.
The disintegration of the institutions of centralized control over the agricultural sector triggered a rapid, widespread LCLUC event. Without planting schedules or crop energy subsidies in the form of fertilizers, pesticides, and fuel, or access to markets, the agricultural sector contracted sharply during the 1990s throughout the former Soviet Union and its client states. There were significant consequent changes in biogeophysical processes, including the onset and timing of land surface phenology (LSP) that links the ecological dynamics of the vegetated surface with the atmospheric dynamics of the planetary boundary layer.
To establish that significant changes had occurred, the project developed a new statistical framework for the analysis of image time series (that included robust tests for step changes, trends, and seasonal functional responses) and techniques sensitive to changes in moderate-to-high vegetation density (http://calmit.unl.edu/kz). Analyzing the Pathfinder AVHRR Land (PAL) NDVI dataset as a function of accumulated growing degree-day using two different spatial partitionings, only three significant patterns of change in LSP, shown bellow, were observed across Kazakhstan out of 14 possible patterns: (1) increased NDVI throughout the growing season; (2) higher NDVI earlier in the growing season; and (3) earlier green-up with increased seasonal integral of NDVI. The principal mechanism behind these changes in LSP was widespread agricultural deintensification in the forms of increased proportions of fallow fields in the rain-fed grain belt and decreased grazing intensities in pastures due to declines in livestock herds. This quantitative change analysis framework has been successfully extended to different ecoregions and biomes in Eurasia, including tundra, taiga, and desert.
Responses of coastal waters to terrestrial inputs of elemental CNP in urbanizing coastal regions
Thomas R. Fisher, Horn Point Laboratory, University of Maryland; Anatoly A. Gitelson, University of Nebraska- Lincoln (Principal Investigators); Michael Williams, EPA, Chesapeake Bay Program Office; Donald C. Rundquist, School of Natural Resources, CALMIT, UNL
Spatial estuarine patterns of turbidity in Chesapeake Bay (center) and Delaware Bay (upper right) derived from a 250 m resolution MODIS image obtained in June 2002.
The US coastal zone has long been impacted by human populations. Many coastal areas were converted from forests to agriculture in the 18th and 19th centuries, and in the second half of the 20th century widespread application of fertilizers increased crop yields to feed human populations. This more intensive agriculture also resulted in greater export of nitrogen and phosphorus, and the chemistry of non-tidal waters is now determined by upstream agriculture in rural areas. Human populations grew rapidly during the second half of the 20th century, particularly in coastal areas. Urbanization resulted in increasing imports of food and export of human waste.
The Chesapeake Bay and the Mississippi plume are regions which have received large quantities of N and P from agriculture and human wastes and which have developed symptoms of eutrophication such as algal blooms, loss of transparency, and hypoxia. However, other coastal regions such as the Delaware Bay and the Hudson estuary receive equally large inputs (scaled to area or volume), but these exhibit little enhanced turbidity, phytoplankton biomass, and hypoxia.
The focus of this research is the spatial variation in sensitivity to nutrient loading from urbanization and agriculture. This team of researchers is testing the hypothesis that the water-residence time determines the sensitivity of estuarine systems to terrestrial nutrient inputs in three Mid-Atlantic estuarine systems: Chesapeake Bay, Delaware Bay, and the Hudson River estuary. MODIS imagery is used to derive spatial estuarine patterns of turbidity and chlorophyll a in response to nutrient loading from surrounding basins. The hypothesis will be tested by (1) estimating urbanization in coastal areas using historical and current AVHRR, Landsat TM, and MODIS imagery, (2) calculating nutrient inputs to these estuarine systems using USGS measurements, municipal wastewater records, and hydrochemical modeling of ungauged areas; (3) applying MODIS and SeaWiFS data to estimate turbidity and chlorophyll-a in turbid productive waters of estuaries; and (4) estimating water residence times using bathymetry, tides, salinity distributions, and stratification. This approach will be used to distinguish between nutrient-sensitive and insensitive coastal regions in order to provide a method for classifying coastal waters into regions in which urbanization and agriculture have negative consequences for water quality.
Agriculture and the Transformation of Planet Earth
Jon Foley (Principal Investigator), Mike Coe, Chris Kucharik, Navin Ramankutty, Carol Barford, Center for Sustainability and the Global Environment, University of Wisconsin, Madison
Worldwide extent of human land use and land-cover change. The maps illustrate the geographic distribution of “potential vegetation” (top panel, vegetation that would probably exist in the absence of human land use) and the extent of agricultural land cover (including croplands and pastures, middle and bottom panels) across the world in the 1990s (Foley et al. 2005. Science 309:570-574). Download higher resolution image.
The rise of modern agriculture, coupled with the massive population increases and technological developments of recent decades, has transformed about one-third of the Earths land surface into croplands and pastures. In addition, the widespread use of fertilizers and irrigation has drastically affected water and nutrient balances across large regions of the globe. Such changes to the land have driven fundamental shifts in the ecological, biogeochemical and hydrological systems of the planet. Even the effects of future climate change may not have such a major transformative effect on the environment and on human society.
However, despite the importance of agriculture on environmental systems, we still know relatively little about how these domains interact across local, regional and global scales. With NASA IDS funding, this research team is investigating how a variety of human and environmental drivers affect the condition of agroecosystems and freshwater systems on regional and global scales. This work is done at the global scale to identify and better document agricultural land cover and land use practices, and their consequences on large-scale water, carbon and nitrogen budgets. We also conduct more detailed regional-scale studies in the Mississippi basin to improve our understanding of the linkages between atmospheric, ecological, biogeochemical and hydrological processes in agriculturally dominated regions.
Regional Hydrological Response of Semi-Arid Mediterranean Climate Watersheds to Land-Cover/Land-Use Variability
Allen Hope (Principal Investigator), San Diego State University; Douglas Stow, San Diego State University; Terence Newby, Agricultural Research Council, South Africa
The Working for Water Program was initiated in 1995 to clear invasive vegetation from watersheds in South Africa. Close to 300,000 Ha are undergoing clearing in the Western Cape Region (red polygons).
This project was launched in October 2005. It has two broad components, the first being to relate watershed land-cover/land-use (LCLUC) and physiographic variables to the parameters of a parsimonious, lumped-parameter, conceptual model (such as the IHACRES model). The LCLUC variables will be derived from MODIS products and physiographic variables will be calculated from Shuttle Radar Topography Mission (SRTM) terrain data. Hydrographic and meteorological data for all gauged watersheds (area range 100 - 4,000 km2) in the Mediterranean-climate regions of California and the Western Cape Province of South Africa (fynbos biome) will be used in this regionalization study.
The objectives of this study are consistent with the International Association of Hydrological Sciences (IAHS) Decade on Predictions in Ungauged Basins (PUB) initiative, which calls for a specific focus on predictive uncertainty, regional analyses based on available gauged data and the assimilation of new data (remote sensing). A major outcome of this project is expected to be a regional hydrological modeling system for simulating river flows in ungauged watersheds accompanied by quantitative indicators of predictive uncertainty. The second component of the project will exploit recent rapid and large scale transformations of ecosystems in California (fire) and South Africa (invasive vegetation removal) to quantify their effects on river flow regimes. Both modeling and paired watershed analyses will be used in this component of the project. MODIS products of LCLUC will be used to quantify changes in the study watersheds.
The Role of Land-Cover Change in Montane Mainland Southeast Asia in Altering Regional Hydrological Processes under a Changing Climate
Jefferson Fox, Tom Giambelluca (Principal Investigators), University of Hawaii
Montane mainland Southeast Asia (MMSEA), situated within the Greater Mekong Subregion, is an area of great biological and cultural diversity that has come under close scrutiny because of deforestation, land degradation, road development, and the conversion of traditional agricultural land uses to more permanent agriculture driven by regional and global markets. These changes have important implications for biodiversity, watershed hydrology, local and regional meteorological processes and climate change. This project seeks to understand, characterize and explore the relationships between LCLUC in MMSEA and local and regional moisture and energy fluxes and regional changes in atmospheric circulation.
A multi-scale, historical geospatial database has been acquired for the region and information regarding drivers of LCLUC is being collected and analyzed via Analytical Hierarchy Process and Fuzzy Cognitive Mapping methods. These data and interrelated future scenarios of agricultural, infrastructure and market changes guide the development of a portfolio of LCLUC models at watershed to regional scales using cellular automata, agent-based, and fuzzy cognitive simulation techniques.
The team has installed and begun collecting data from a network of 22 hydrological and climate instruments across two representative, intensive study watersheds in southern Yunnan, China and northern Thailand, each around 100km2. These field observations together with additional biophysical data and LCLUC projections will be used to parameterize and calibrate the distributed hydrological model (DHSVM) for the watersheds. Regional climate simulations are running under present climate conditions (European Centre for Medium-Range Weather Forecasts) with present LCLU and extreme deforestation, and additional experiments are planned using control and projected climate (Parallel Climate Model) with present LCLU and LCLUC projections. More information on this project can be found at: http://research.eastwestcenter.org/mmsea/
Other Energy and Water-Cycle LCLUC Projects:
- Aizen, Vladimir - University of Idaho. Estimation of seasonal snow cover and glacial area changes in central Asia (Tien Shan) during the last 50 years using NASA ESE products and in-situ data
- Anderson, Martha - University of Wisconsin-Madison. Multi-scale remote assessment of land-surface hydrologic response to natural and anthropogenic stressors: a case study in the Florida Evergaldes
- Brown, Dan - University of Michigan. Changing Responses of Land Dynamics and Vulnerability to Flooding Under Policy and Environmental Change near Poyang Lake, China
- Chen, Jiquan - The University of Toledo. Effects of land-use change on the energy and water balance of the semi-arid region of inner Mongolia
- Davidson, Eric - Woods Hole Research Center. Interactions of Edaphic and Land Use Factors on Water Budgets in Cerrado and Semi-Arid Caatinga Region of Brazil
- Eshleman, Keith - University of Maryland. Exacerbation of Flooding Responses Due to Land Cover/Land-Use Change: A Comparative Study
- Gitelson, Anatoly - University of Nebraska-Lincoln. Land-cover land-use change effects on surface water quality: Integrated MODIS and SeaWiFS assessment of the Dnieper and Don River basins and their reservoirs
- Marc, Imhoff - Goddard Space Flight Center. Global Distribution of Human Appropriation of Fresh Water: An Earth Observation-supported Strategy Linking Biophysics and Socio-economics for Addressing Water Vulnerability
- Munroe, Darla - Ohio State University. A Comprehensive Statistical Analysis System to Associate Local Land-Cover/Land-Use Change and Regional Aerosol Composition and Concentration
- Townsend, Phil - University of Wisconsin. Spatial Patterns of Forest Disturbance and Consequences for Regional Water Quality
- Vorosmarty, Charles - University of New Hampshire. Role of land cover and land-use change in hydrology of Eurasian pan-Arctic
- Zeng, Xubin - University of Arizona. Relationship between Land Cover/Land-Use Change and Surface Hydrology over Arid and Semiarid Regions
