Ralph J. Alig

CLIMATE CHANGE AND FUTURE LAND USE IN THE UNITED STATES: AN ECONOMIC APPROACH

An econometric land-use model is used to project regional and national land-use changes in the United States under two IPCC emissions scenarios. The key driver of land-use change in the model is county-level measures of net returns to five major land uses. The net returns are modified for the IPCC scenarios according to assumed trends in population and income and projections from integrated assessment models of agricultural prices and agricultural and forestry yields. For both scenarios, we project large increases in urban land by the middle of the century, while the largest declines are in cropland area. Significant differences among regions in the projected patterns of land-use change are evident, including an expansion of forests in the Mountain and Plains regions with declines elsewhere. Comparisons to projections with no climate change effects on prices and yields reveal relatively small differences. Thus, our findings suggest that future land-use patterns in the U.S. will be shaped largely by urbanization, with climate change having a relatively small influence.

National forests on the edge: development pressures on America's national forests and grasslands.

Many of America’s national forests and grasslands—collectively called the National Forest System—face increased risks and alterations from escalating housing development on private rural lands along their boundaries. National forests and grasslands provide critical social, ecological, and economic benefits to the American public. This study projects future housing density increases on private rural lands at three distances—2, 3, and 10 miles—from the external boundaries of all national forests and grasslands across the conterminous United States. Some 21.7 million acres of rural private lands (about 8 percent of all private lands) located within 10 miles of the National Forest System boundaries are projected to undergo increases in housing density by 2030. Nine national forests are projected to experience increased housing density on at least 25 percent of adjacent private lands at one or more of the distances considered. Thirteen national forests and grasslands are each projected to have more than a half-million acres of adjacent private rural lands experience increased housing density. Such development and accompanying landscape fragmentation pose substantial challenges for the management and conservation of the ecosystem services and amenity resources of National Forest System lands, including access by the public. Research such as this can help planners, managers, and communities consider the impacts of local land use decisions.

Sustaining America's urban trees and forests: a Forests on the Edge report

Close to 80 percent of the U.S. population lives in urban areas and depends on the essential ecological, economic, and social benefits provided by urban trees and forests. However, the distribution of urban tree cover and the benefits of urban forests vary across the United States, as do the challenges of sustaining this important resource. As urban areas expand across the country, the importance of the benefits that urban forests provide, as well as the challenges to their conservation and maintenance, will increase. The purpose of this report is to provide an overview of the current status and benefits of Americas urban forests, compare differences in urban forest canopy cover among regions, and discuss challenges facing urban forests and their implications for urban forest management.

Linking land-use projections and forest fragmentation analysis.

An econometric model of private land-use decisions is used to project land use to 2030 for each county in the continental United States. On a national scale, forest area is projected to increase overall between 0.1 and 0.2 percent per year between now and 2030. However, forest area is projected to decrease in a majority of regions, including the key forestry regions of the South and the Pacific Northwest westside. Urban area is projected to increase by 68 million acres, and cropland, pasture, rangeland, and Conservation Reserve Program land is projected to decline in area. Regional econometric models are needed to better represent region-specific economic relationships. County-level models of forest fragmentation indices are estimated for the Western United States. The core forest model is found to perform better than the model of like adjacencies for forest land. A spatially detailed analysis of forest fragmentation in Polk County, Oregon, reveals that forests become more fragmented even though forest area increases. By linking the land-use projection and forest fragmentation models, we project increases in the average county shares of core forest in 8 of the 11 Western States. The average like adjacency measure increases in six of the states. The aggregate and spatially detailed fragmentation methods are compared by projecting the fragmentation indices to 2022 for Polk County, Oregon. Considerable differences in the results were produced with the two methods, especially in the case of the like adjacency metric.

Consideration of country and forestry/ land‐use characteristics in choosing forestry instruments to achieve climate mitigation goals

Abstract To implement effective carbon sequestration policies policymakers must analyze key characteristics of the country (geographic, institutional, economic, and infrastructural factors) and forestry and land‐use practices (the degree of risk associated with investment, the relative difficulty in measuring sequestration, and the degree of discretion allowed). Without careful analysis of this type, policies may have unintended negative effects.

New cost estimates for carbon sequestration through afforestation in the United States

This report provides new cost estimates for carbon sequestration through afforestation in the United States. We extend existing studies of carbon sequestration costs in several important ways, while ensuring the transparency of our approach. We clearly identify all components of our cost estimates so that other researchers can reconstruct our results as well as use our data for other purposes. Our cost estimates have five distinguishing features: (1) we estimate costs for each county in the contiguous United States; (2) we include afforestation of rangeland, in addition to cropland and pasture; (3) our opportunity cost estimates account for capitalized returns to future development (including associated option values) in addition to returns to agricultural production; (4) we develop a new set of forest establishment costs for each county; and (5) we incorporate data on Holdridge life zones to limit afforestation in locations where temperature and moisture availability prohibit forest growth. We find that at a carbon price of

A spatial econometric analysis of land-use change with land cover trends data: an application to the Pacific Northwest

50/ton, approximately 200 million tons of carbon would be sequestered annually through afforestation. At a price of

Methods for Projecting Areas of Private Timberland and Forest Cover Types

100/ton, an additional 100 million tons of carbon would be sequestered each year. Our estimates closely match those in earlier econometric studies for relatively low carbon prices, but diverge at higher carbon prices. Accounting for climatic constraints on forest expansion has important effects on cost estimates. To access county-level data on land prices, tree establishment costs, carbon uptake rates, and eligible land for conversion to forest, follow this link: http://www.fs.fed.us/pnw/pubs/pnw_gtr888/county-level-data_nielsen2013.xlsx

Mitigating climate change through afforestation: new cost estimates for the United States

This paper develops a plot-level spatial econometric land-use model and estimates it with U.S. Geological Survey Land Cover Trends (LCT) geographic information system panel data for the western halves of the states of Oregon and Washington. The discrete-choice framework we use models plot-scale choices of the three dominant land uses in this region: forest, agriculture, and urban development. The results provide a technical foundation for developing larger scale models from the LCT database. In particular, we develop a random-effects estimation method for dealing with the spatially clustered sample design underlying the LCT. We also exploit the increased spatial information content available in the LCT by exploring the estimation of a fully spatial multinomial discrete-choice land-use model by including measures of land-use agglomeration economies as independent variables in estimation. Estimation of the spatial econometric model includes a novel combination of panel-data random parameters logit estimation with instrumental variables implemented within the recently developed control function approach. The estimated econometric model is used to project landscape change in the presence of alternative assumptions regarding future urban returns. Our results indicate that variation in urban returns on the order of what was experienced in the housing boom and bust of the 2000s generates a wide range of predicted future land-use shares in developed uses. The Puget Lowland ecoregion has by far the most sensitive landscape projections in response to wide swings in urban returns.

Regional Cost Information for Private Timberland Conversion and Management

We summarize methods used to project area changes in land uses and forest cover types in the national RPA Timber Assessments over the last 20 years, since area projection modeling systems replaced expert opinion approaches. Such models reflect that key land base changes such as afforestation and deforestation are driven by quite different socioeconomic factors. The prototype area-change modeling system—the AREACHANGE projection system—was constructed in the early 1980s for the South to support a special study between periodic RPA Timber Assessments. The southern prototype involved an area-base econometric approach, which has been applied in later RPA Timber Assessments regions and revised for the South. Other econometric models were developed in the late 1980s and later decades for the Pacific Northwest, Lake States, Maine, and other regions. Timber price projections from the Timber Assessment Projection Systems modeling of markets are used as inputs in the first stage of the area-change projections. Timber harvest projections from the TAMM model, as allocated to management units by the ATLAS model, along with timber management projections from the ATLAS model are used as inputs in the second stage of projecting area changes in major forest cover types. The AREACHANGE system provides the ATLAS system with projections of timberland area by region, ownership, and major forest type. The progression of area-change modeling was heavily dependent on the availability of land-use data.