Jennifer L. Pierce

Fire-induced erosion and millennial-scale climate change in northern ponderosa pine forests

Western US ponderosa pine forests have recently suffered extensive stand-replacing fires followed by hillslope erosion and sedimentation. These fires are usually attributed to increased stand density as a result of fire suppression, grazing and other land use, and are often considered uncharacteristic or unprecedented. Tree-ring records from the past 500 years indicate that before Euro-American settlement, frequent, low-severity fires maintained open stands. However, the pre-settlement period between about ad 1500 and ad 1900 was also generally colder than present, raising the possibility that rapid twentieth-century warming promoted recent catastrophic fires. Here we date fire-related sediment deposits in alluvial fans in central Idaho to reconstruct Holocene fire history in xeric ponderosa pine forests and examine links to climate. We find that colder periods experienced frequent low-severity fires, probably fuelled by increased understory growth. Warmer periods experienced severe droughts, stand-replacing fires and large debris-flow events that comprise a large component of long-term erosion and coincide with similar events in sub-alpine forests of Yellowstone National Park. Our results suggest that given the powerful influence of climate, restoration of processes typical of pre-settlement times may be difficult in a warmer future that promotes severe fires.

THE SIGNIFICANCE OF RACE AND GENDER IN SCHOOL SUCCESS AMONG LATINAS AND LATINOS IN COLLEGE

This article considers how race and gender shape latina and Latino paths to school success in college. A purposive sample of successful high school and college students was selected. Through interviews, fieldwork, and school records, the researchers find that Latinas navigate successfully through negative stereotypes by maintaining positive definitions of themselves and by emphasizing their group membership as Latina. Young Latino men also see themselves as part of a larger cultural group but tend to have less positive racial and ethnic identities than women do. Typically, they are supported by mentors, such as white athletic coaches, and tend to draw from the meritocratic ethos of sports, regarding their success in individualistic terms. While successful Latinas do not assimilate in the ways predicted by the literature, the young men in this study accept the individualistic and meritocratic ethos of the dominant culture, but with a psychological price.

Climatic controls on fire-induced sediment pulses in Yellowstone National Park and central Idaho: a long-term perspective

Fire management addressing postfire erosion and aquatic ecosystems tends to focus on short-term effects persisting up to about a decade after fire. A longer perspective is important in understanding natural variability in postfire erosion and sedimentation, the role of these processes in structuring habitat, and future expectations in light of a warming climate and environmental change. In cool high-elevation forests of northern Yellowstone National Park, stand ages indicate infrequent large stand-replacing fires. In warmer low-elevation forests of the Payette River region of Idaho, fire-scarred tree-rings record frequent low-severity fires before 1900; stand-replacing fires and resulting debris flows in recent decades are usually attributed to 20thcentury fire suppression, grazing, and other land uses. In both areas, however, tree-ring records extend back only about 500 years. We use 14 C-dated geologic records to examine spatial and temporal patterns of fire-induced sedimentation and its relation to climate over the last 10 000 years. We review sedimentation processes in modern postfire events, which vary in magnitude and impact on stream systems depending on burn severity, basin geomorphology, and the timing and characteristics of postfire storms. Modern deposits also provide analogs for identification of fire-related deposits in alluvial fans. In Yellowstone, episodes of fire-induced sedimentation occurred at intervals of about 300‐450 years during the last 3500 years, indicating a regime of infrequent high-severity fires. Millennial-scale variations in the fire-sedimentation record appear to relate to hemispheric-scale climatic change. Fire-related sedimentation is rare in Yellowstone during cooler episodes (e.g., the Little Ice Age � 1200‐1900 A.D.), probably because effectively wetter conditions prevented most fires from spreading. During some of the same cool periods, the Payette region experienced light surface fires and frequent, small pulses of fire-induced sediment. Between 900 and 1200 A.D., however, large fire-related debris flows occurred in both study areas, coincident with the Medieval Warm Period. During that time, drought may have limited grass growth in xeric Payette-region forests, restricting surface fire spread and allowing understory shrubs and trees to create ladder fuels. Although fire suppression and land-use effects are clearly involved in recent catastrophic fires in the Payette region, a warming climate and severe drought are probable contributors to major stand-replacing fires and postfire sedimentation, both past and present. Restoration and maintenance of conditions prior to European settlement may be unrealistic because of the potent influence of climate, and the incidence of severe fires will likely increase in both areas with future warming. # 2003 Elsevier Science B.V. All rights reserved.

Sibship Size and Educational Attainment in Nuclear and Extended Families: Arabs and Jews in Israel.

We examine the relationship between number of siblings and educational attainment for three groups in Israel: Ashkenazi Jews, Oriental Jews, and Moslem Arabs. For both Jewish groups number of siblings has a negative effect on educational attainment. However, this pattern is not replicated for Moslems whose social organization is based largely on the extended family and the patrilineage (the hamula). Among Moslems the extended family plays an active supporting role vis-a-vis the nuclear family. While the size of the nuclear family does not affect educational attainment for Moslems in Israel, the size of the hamula does. This suggests that when the nuclear family draws on the support of an extended kinship, its size is less important for the educational attainment of children.

“Racing for Innocence”: Whiteness, Corporate Culture, and the Backlash Against Affirmative Action

This paper argues that “racing for innocence” is a discursive practice which functions simultaneously to disavow accountability for racist practices at the same time that everyday racism is practiced. Drawing from both fieldwork and interviews in a corporate legal department over two different time periods (in 1988–89 and in 1999), I explore the meaning and consequence of this “race” in my interviews with white and African-American lawyers. Further, I follow the trajectory of one African-American lawyer, Randall Kingsley, and tell his story along with the stories constructed by the white men who still work there about Randalls departure from the company. I do so to make an argument about why these white men, by virtue of their social location, cannot see how they contributed to the unfriendly climate that forced Randall out of the department. Further, I argue it is through such everyday practices that whiteness is reproduced as a structural relationship of inequality in workplaces.

Emotional Labor Among Paralegals

Despite the invisibility of emotional labor among paralegals, this dimension of work has significant consequences for the reproduction of the labor process in the large bureaucratic firm and for the psychological well-being of paralegals. These legal workers function to support and maintain the emotional stability of the lawyers for whom they work through deferential treatment and caretaking. By affirming the status of lawyers, paralegals also reproduce gender relations in the law firm. Most attorneys who receive caretaking and support are men, and the majority of the legal assistants who provide these emotional services are women. In this way, the emotional labor required of paralegals serves to reproduce the sex-segregated structure of law firms.

Long-term fire history from alluvial fan sediments: the role of drought and climate variability, and implications for management of Rocky Mountain forests

Alluvial fan deposits are widespread and preserve millennial-length records of fire. We used these records to examine changes in fire regimes over the last 2000 years in Yellowstone National Park mixed-conifer forests and drier central Idaho ponderosa pine forests. In Idaho, frequent, small, fire-related erosional events occurred within the Little Ice Age (~1450–1800 AD), when greater effective moisture probably promoted grass growth and low-severity fires. This regime is consistent with tree-ring records showing generally wetter conditions and frequent fires before European settlement. At higher elevations in Yellowstone, cool conditions limited overall fire activity. Conversely, both Idaho and Yellowstone experienced a peak in fire-related debris flows between ~950 and 1150 AD. During this generally warmer time, severe multidecadal droughts were interspersed with unusually wet intervals that probably increased forest densities, producing stand-replacing fires. Thus, severe fires are clearly within the natural range of variability in Idaho ponderosa pine forests over longer timescales. Historical records indicate that large burn areas in Idaho correspond with drought intervals within the past 100 years and that burn area has increased markedly since ~1985. Recent stand-replacing fires in ponderosa pine forests are likely related to both changes in management and increasing temperatures and drought severity during the 20th century.

Forecasting the response of Earth's surface to future climatic and land use changes: A review of methods and research needs

In the future, Earth will be warmer, precipitation events will be more extreme, global mean sea level will rise, and many arid and semiarid regions will be drier. Human modifications of landscapes will also occur at an accelerated rate as developed areas increase in size and population density. We now have gridded global forecasts, being continually improved, of the climatic and land use changes (C&LUC) that are likely to occur in the coming decades. However, besides a few exceptions, consensus forecasts do not exist for how these C&LUC will likely impact Earth-surface processes and hazards. In some cases, we have the tools to forecast the geomorphic responses to likely future C&LUC. Fully exploiting these models and utilizing these tools will require close collaboration among Earth-surface scientists and Earth-system modelers. This paper assesses the state-of-the-art tools and data that are being used or could be used to forecast changes in the state of Earths surface as a result of likely future C&LUC. We also propose strategies for filling key knowledge gaps, emphasizing where additional basic research and/or collaboration across disciplines are necessary. The main body of the paper addresses cross-cutting issues, including the importance of nonlinear/threshold-dominated interactions among topography, vegetation, and sediment transport, as well as the importance of alternate stable states and extreme, rare events for understanding and forecasting Earth-surface response to C&LUC. Five supplements delve into different scales or process zones (global-scale assessments and fluvial, aeolian, glacial/periglacial, and coastal process zones) in detail.

Anticipating Stream Ecosystem Responses to Climate Change: Toward Predictions that Incorporate Effects Via Land-Water Linkages

Climate change (CC) is projected to increase the frequency and severity of natural disturbances (wildfires, insect outbreaks, and debris flows) and shift distributions of terrestrial ecosystems on a global basis. Although such terrestrial changes may affect stream ecosystems, they have not been incorporated into predictions of stream responses to CC. Here, we introduce a conceptual framework to evaluate to what extent responses of streams to CC will be driven by not only changes in thermal and hydrologic regimes, but also alterations of terrestrial processes. We focused on forested watersheds of western North America because this region is projected to experience CC-induced alteration of terrestrial processes. This provided a backdrop for investigating interactive effects of climate and terrestrial responses on streams. Because stream responses to terrestrial processes have been well-studied in contexts largely independent of CC research, we synthesized this knowledge to demonstrate how CC-induced alterations of terrestrial ecosystems may affect streams. Our synthesis indicated that altered terrestrial processes will change terrestrial–aquatic linkages and autotrophic production, potentially yielding greater sensitivity of streams to CC than would be expected based on shifts in temperature and precipitation regime alone. Despite uncertainties that currently constrain predictions regarding stream responses to these additional pathways of change, this synthesis highlighted broader effects of CC that require additional research. Based on widespread evidence that CC is linked to changing terrestrial processes, we conclude that accurate predictions of CC effects on streams may be coupled to the accuracy of predictions for long-term changes in terrestrial ecosystems.

Late-Holocene relationships among fire, climate and vegetation in a forest-sagebrush ecotone of southwestern Idaho, USA

The forest-sagebrush ecotone is characterized by a more arid climate than forested regions; therefore, establishing fire histories using traditional methods (e.g. fire-scars from trees, charcoal in lake sediments) is problematic. This study uses radiocarbon dating of charcoal preserved in alluvial deposits to reconstruct a record of fire and geomorphic response in southwestern Idaho. Samples indicate three primary periods of fire-related activity: 4400—4000, 2000—1400, and 650—400 cal. yr BP. Charcoal macrofossil identification and comparison with other regional records indicate this area has likely alternated between a ‘fuel-limited’ system (fires limited by lack of fuels), and a ‘moisture-limited’ system (fires limited by too much moisture) with changes in Holocene climate. Over the past ~2000 yr, samples from this site indicate most fires occurred during wetter times than the record average. During overall wetter periods, (e.g. ‘Little Ice Age’ (LIA); 600—100 cal. yr BP) tree density may have increased, and fires occurred during intervals of relative drought. During times of prolonged drought (e.g. ‘Medieval Climate Anomaly’ (MCA); 1025—650 cal. yr BP) fire was recorded during a wetter interval. After ~600 cal. yr BP, fire activity was similar to alluvial charcoal records of low-intensity fires in a nearby ponderosa pine-dominated drainage, and sagebrush is common in charcoal samples. Both the ponderosa site and the Wood Creek site show low fire activity in ~6500—5000 cal yr BP; climatically, ~7—5 ka appears to correspond with regional records of drought. This work provides a unique record of fire in a semi-arid ecotone where (1) few records exist because of the paucity of dating sites, and (2) climatic sensitivity is likely enhanced.