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Given the long-term human habitation and prolific land use change trajectories in the eastern United States, few remnants of the pre-European settlement Mid-Atlantic forest remain on the Atlantic Coastal Plain. This study utilized metes and bounds witness tree locations and descriptions produced during colonial land subdivision to understand the relationships between tree types and biogeographic environments for an area on Maryland's Eastern Shore. Using correspondence analysis, we reveal habitat partitioning among witness tree species based on soil drainage characteristics, that enable the visualization of a pre-European settlement reconstructed forest. Our research finds that oak (Quercus), most often white oak (Quercus alba), was the dominant genus for most of the study area underlain by well-drained soils. To a much smaller extent, gums were also associated with these well-drained soils. Areas of poor drainage most often contained pine (Finns) and an assemblage of different oaks (Quercus spp.). Hickory (Carya), also noted in the witness tree record in small numbers, was found across all soil drainages. Key words: witness trees, precolonial forest, soil drainage, Wicomico Co., Maryland, Introduction The eastern forests of the United States have been greatly affected by anthropogenic activity, first by Native Americans and later by European colonists. The impact of Native Americans on [...]

The Oregon Coast landscape displays strong spatial patterns in air temperature, precipitation, and geology, which can confound our ability to detect relationships among land management, instream conditions, and fish at broad spatial scales. Despite this structure, we found that a suite of immutable or intrinsic attributes (e.g., reach gradient, drainage area, elevation, and percent weak rock geology of the catchments draining to each of our 423 study reaches) could explain much of the variation in pool surface area across the landscape and could contribute to an estimate of how many juvenile coho salmon (Oncorhynchus kisutch) one might expect to find in those pools. Further, we found evidence of differences in pool surface area across land ownership categories that reflect differing management histories. Our results also suggest that historical land and river management activities, in particular splash dams that occurred at least 50 years ago, continue to influence the distribution of juvenile coho salmon and their habitats today. Le paysage du littoral de l'Oregon presente un degre de structure spatiale eleve en ce qui concerne des caracteristiques du paysage comme la temperature de l'air, les precipitations et la geologie. Malgre cette structure sous-jacente, nous avons constate qu'une serie d'attributs immuables ou intrinseques comme, par exemple, le gradient des tronqons, la superficie drainee, l'elevation moyenne du bassin versant et le pourcentage de la geologie constitue de roches peu resistantes des reseaux hydrographiques se deversant dans chacun des 423 tronqons etudies, pourrait expliquer une bonne partie des variations de la superficie des fosses a l'echelle du paysage et pourrait aider a estimer le nombre de saumons cohos (Oncorhynchus kisutch) juveniles possiblement presents dans ces fosses. Nous avons egalement trouve des indices de variation de la superficie des fosses selon la categorie de propriete terrienne qui refletent differents historiques de gestion. Nos resultats donnent a penser que les activites passees de gestion des terres et des rivieres, en particulier le flottage de billots il y a au moins 50 ans, continuent a ce jour d'influencer la repartition des saumons cohos juveniles et leurs habitats. [Traduit par la Redaction], Introduction Understanding the distribution of instream habitats and the density of fish within those habitats is essential for effective watershed management and conservation of depressed fish populations. For wide-ranging species [...]

Land use and land cover change (LULCC) significantly influences the climate system. Hence, to prepare the nation for future climate change and variability, a sustained assessment of LULCC and its climatic impacts needs to be undertaken. To address this objective, not only do we need to determine contemporary trends in land use and land cover that affect, or are affected by, weather and climate but also identify sectors and regions that are most affected by weather and climate variability. Moreover, it is critical that we recognize land cover and regions that are most vulnerable to climate change and how end-use practices are adapting to climate change. This paper identifies a series of steps that need to be undertaken to address these key items. In addition, national-scale institutional capabilities are identified and discussed. Included in the discussions are challenges and opportunities for collaboration among these institutions for a sustained assessment., Sustained assessment of the climatic impacts of land use and land cover change is essential. Land use and land cover change (LULCC) plays an important role in the climate system. [...]

This study examined how interactions between natural landscape features and land use influenced the abundance of smallmouth bass, Micropterus dolomieu, in Missouri, USA, streams. Stream segments were placed into one of four groups based on natural-occurring watershed characteristics (soil texture and soil permeability) predicted to relate to smallmouth bass abundance. Within each group, stream segments were assigned forest (n = 3), pasture (n = 3), or urban (n = 3) designations based on the percentages of land use within each watershed. Analyses of variance indicated smallmouth bass densities differed between land use and natural conditions. Decision tree models indicated abundance was highest in forested stream segments and lowest in urban stream segments, regardless of group designation. Land use explained the most variation in decision tree models, but in-channel features of temperature, flow, and sediment also contributed significantly. These results are unique and indicate the importance of natural-occurring watershed conditions in defining the potential of populations and how finer-scale filters interact with land use to further alter population potential. Smallmouth bass has differing vulnerabilities to land-use attributes, and the better the natural watershed conditions are for population success, the more resilient these populations will be when land conversion occurs. Notre etude examine comment les interactions entre les caracteristiques du paysage naturel et l'utilisation des terres influencent l'abondance des achigans a petite bouche, Micropterus dolomieu, dans des cours d'eau du Missouri, E.-U. Les segments de cours d' eau ont ete repartis en quatre groupes d' apres les caracteristiques naturelles de leur bassin versant (texture et permeabilite des sols) presumees etre en relation avec l'abondance des achigans a petite bouche. Dans chaque groupe, les segments de cours d' eau ont recu des etiquettes de foret (n = 3), de paturage (n = 3) ou de zone urbaine (n = 3) d'apres les pourcentages d'utilisation des terres dans chaque bassin versant. Des analyses de variance montrent que les densites d' achigans a petite bouche varient en fonction de l' utilisation des terres et des conditions naturelles. Des modeles d' arbres de decision indiquent que l' abondance est maximale dans les segments de cours d' eau en foret et minimale dans les segments de cours d'eau urbains, quelle que soit la designation du groupe. L'utilisation des terres explique le plus de variation dans les modeles d' arbres de decision, mais les caracteristiques internes du chenal, temperature, debit et sediments, contribuent aussi de maniere significative. Ces resultats sont inedits et ils indiquent l'importance des conditions naturelles du bassin versant pour definir le potentiel demographique; ils montrent comme les filtres a echelles plus fines interagissent avec l' utilisation des terres pour modifier encore plus le potentiel demographique. Les achigans a petite bouche possedent des vulnerabilites differentes aux diverses caracteristiques de l'utilisation des terres; plus les conditions naturelles du bassin versant sont favorables au succes de la population, plus la population sera resiliente lorsqu' il se produira une modification dans l' utilisation des terres. [Traduit par la Redaction], Introduction Recognition of the vast extent and ecological importance of land-use changes worldwide (Turner and Meyer 1994) has resulted in increasing numbers of studies examining effects of land-use changes on [...]

Recent and projected climate warming trends have prompted interest in impacts on coldwater fishes. We examined the role of climate (temperature and flow regime) relative to geomorphology and land use in determining the observed distributions of three trout species in the interior Columbia River Basin, USA. We considered two native species, cutthroat trout (Oncorhynchus clarkii) and bull trout (Salvelinus confluentus), as well as nonnative brook trout (Salvelinus fontinalis). We also examined the response of the native species to the presence of brook trout. Analyses were conducted using multilevel logistic regression applied to a geographically broad database of 4165 fish surveys. The results indicated that bull trout distributions were strongly related to climatic factors, and more weakly related to the presence of brook trout and geomorphic variables. Cutthroat trout distributions were weakly related to climate but strongly related to the presence of brook trout. Brook trout distributions were related to both climate and geomorphic variables, including proximity to unconfined valley bottoms. We conclude that brook trout and bull trout are likely to be adversely affected by climate warming, whereas cutthroat trout may be less sensitive. The results illustrate the importance of considering species interactions and flow regime alongside temperature in understanding climate effects on fish. Les tendances recentes et prevues de rechauffement du climat ont suscite de l'interet pour les impacts sur les poissons d'eau froide. Nous examinons le role du climat (temperature et regime hydraulique) en fonction de la geomorphologie et de l'utilisation des terres dans la determination de la repartition observee chez trois especes de <> dans le bassin versant interieur du Columbia, E.-U. Nous observons deux especes indigenes, la truite fardee (Oncorhynchus clarkii)et l'omble a tete plate (Salvelinus confluentus), ainsi que l'omble de fontaine (Salvelinus fontinalis) non indigene. Nous etudions aussi la reaction des especes indigenes a la presence de l'omble de fontaine. Les analyses consistent en des regressions logistiques a niveaux multiples sur une base de donnees de grande envergure geographique de 4165 inventaires de poissons. Les resultats indiquent que les repartitions des ombles a tete plate sont fortement reliees aux facteurs climatiques et moins fortement correlees a la presence d'ombles de fontaine et aux variables geomorphologiques. Les repartitions des truites fardees sont faiblement reliees au climat, mais fortement reliees a la presence de l'omble de fontaine. Les repartitions des ombles de fontaine sont reliees a la fois au climat et aux variables geomorphologiques, en particulier la proximite des fonds de vallees elargis. Nous concluons que l'omble de fontaine et l'omble a tete plate seront vraisemblablement affectes negativement par le rechauffement climatique, alors que la truite fardee sera peut-etre moins sensible. Nos resultats soulignent l'importance de considerer les interactions entre les especes et le regime hydraulique en plus de la temperature pour comprendre les effets du climat sur les poissons. [Traduit par la Redaction], Introduction Recent warming trends and projections of future climate change have prompted interest in the climate sensitivity of aquatic organisms (Parmesan 2006; Battin et al. 2007; McCullough et al. 2009). [...]

ABSTRACT An urban community [PM.sub.10] (particulate matter [less than or equal to] 10 µm in aerodynamic diameter) air pollution study was conducted in Paterson, NJ, a mixed land-use community that [...]

Land-use history can play a significant role in shaping forest communities. We considered the effects of agricultural land-use legacies on the distribution of non-native invasive plants a century after abandonment in a watershed in western North Carolina, USA. Forest sites that were previously in cultivation and abandoned ca. 1905 were compared with nearby reference sites that were never cultivated. The most common invasive plants were Celastrus orbiculatus Thunb., Microstegium vimineum Trin., and Lonicera japonica Thunb. Formerly cultivated sites and plots positioned downslope from roads had the most invasives. Soil cation concentration and pH were positively correlated with invasive presence and abundance. Historic agricultural plots where the successional tree Liriodendron tulipifera L. was dominant had the highest soil cation concentrations and soil pH and the greatest abundance of invasive plants. Disentangling the cause-effect relationships between land-use history, the biotic community, and the abiotic template presents a challenge, but understanding the role of land-use legacies may provide important insights regarding the mechanisms underlying the establishment and spread of invasive plants in forest ecosystems. Our results suggest that land-use history at Bent Creek may be facilitating plant invasion indirectly by causing a shift in overstory community composition that in turn creates more suitable understory conditions for shade-tolerant invasive plants. L'utilisation passee des terres peut jouer un role important dans la formation des communautes forestieres. Nous avons examine les effets de l'utilisation passee des terres a des fins agricoles sur la distribution des plantes exotiques invasives, un siecle apres l'abandon de l'agriculture dans un bassin versant le l'ouest de la Caroline du Nord, aux etats-Unis. Les stations forestieres precedemment cultivees et abandonnees autour de 1905 ont ete comparees a des stations temoins situees a proximite et qui n'ont jamais ete cultivees. Les plantes invasives les plus frequentes etaient Celastrus orbiculatus Thunb., Microstegium vimineum Trin. et Lonicera japonica Thunb. Les stations precedemment cultivees et les parcelles situees en aval d'un chemin avaient la plus grande quantite de plantes invasives. La concentration des cations et le pH du sol etaient positivement correles avec la presence de plantes invasives et leur abondance. Les parcelles jadis occupees par l'agriculture, ou dominait l'espece successionnelle Liriodendron tulipifera L., avaient les plus fortes concentrations de cations dans le sol, le pH du sol le plus eleve et la plus grande abondance de plantes invasives. C'est un defi de demeler les relations de cause a effet entre l'utilisation passee des terres, la communaute biotique et la plate-forme abiotique mais la comprehension du role de l'heritage laisse par l'utilisation des terres peut fournir de precieuses indications concernant les mecanismes sous-jacents a l'etablissement et a la propagation des plantes invasives dans les ecosystemes forestiers. Nos resultats indiquent que l'utilisation passee des terres a Bent Creek pourrait indirectement faciliter l'invasion des plantes en provoquant un changement dans la composition de la communaute de l'etage dominant qui a son tour cree des conditions plus favorables en sousbois pour les plantes invasives tolerantes a l'ombre. [Traduit par la Redaction], Introduction Non-native invasive plants represent a significant driver of change in natural ecosystems by displacing native species, disrupting succession, and altering ecosystem structure and function (Vitousek et al. 1996). A [...]

Contemporary land-use pressures have a significant impact on the extent and condition of forests in the eastern United States, causing a regional-scale decline in forest cover. Earlier in the 20th [...]

Releases of greenhouse gases (GHG) from indirect land-use change triggered by crop-based biofuels have taken center stage in the debate over the role of biofuels in climate policy and energy [...]

'They never amount to anything. Won't improve the land because they don't intend to stay or afraid they'll drive the rent up. Damn poor farmers' From Old Jules, by Mari [...]

As natural amenities attract people and commerce to the rural west, the resulting land-use changes threaten biodiversity, even in protected areas, and challenge efforts to sustain local communities and ecosystems. [...]

Introduction Good afternoon. My name is Corinne Conner. I am a Fish and Wildlife Service biologist in Austin, Texas. I am also a joint owner and manager of Bee Cave [...]

One species that typifies the northern forests of the eastern United States in the minds of many ecologists and naturalists is the eastern white pine (Pinus strobus L.). Its range [...]

A deficiency common to both the historical debates over loss of agricultural land and the current discussions of urbanization and sprawl is a limited understanding of land-use dynamics beyond the urban fringe. Data aggregated at the county level poorly capture the fine-grained pattern of land-use change beyond the dynamic urban-rural interface. Furthermore, current urban-based definitions are poorly suited to delineate these areas, and low-density, exurban land use is difficult to measure using existing land-cover databases. Urbanization and the conversion of once-agricultural or other natural resource lands to other uses has traditionally been tracked using urban areas, as delimited in the U.S. census. Urban densities are typically defined as areas with more than 1,000 people per square mile, or 1.6 people per acre (U.S. Census Bureau 2000). Assuming an average of 2.5 people per housing unit, this translates to roughly 0.7 units per acre, or approximately 1 unit per 1.6 acres. The analytical units used in the census, however, both overbound and underbound areas with urban densities. About one-third of urban areas in 1990 comprised lower-than-urban housing density, thanks to overbounding. But, then, one-third of locations that had urban-level housing densities failed to be included in urban areas as a result of underbounding, which, if counted, would have constituted another 18 million acres of urban area. An increase over time of the average number of acres required per housing unit in exurban and higher-density locations occurred in roughly one-third of U.S. counties from 1960 to 1990 and persisted from 1990 to 2000. In 2000 roughly 38 million acres were settled at urban densities, and nearly ten times that much land was settled at rates from low, exurban density (as low as one house per 40 acres) to higher rates (up to one per 10 acres). This represents a continuing encroachment on land previously given over to other uses--habitat or agriculture. Practitioners of natural resource management need to r ecognize the ubiquity of exurban development and better incorporate the fine-scale patterns of land use beyond the urban fringe. Keywords: agriculture, exurbia, land use, sprawl, urbanization., In 1950 the condition of agriculture in the United States quietly reached a turning point. From the late 1800s until 1950, farmland expanded rapidly to eventually include 1,161 million acres. [...]

CAN AMERICA'S SPRAWLING, car-choked, urban wastelands be saved? Can the nation's great metropolitan areas ever become more than a joyless succession of edge cities--those bleak aggregations of office boxes that [...]

INTERACTIONS BETWEEN CLIMATE CHANGE AND LAND USE ARE PROJECTED TO CAUSE LARGE SHIFTS IN BIODIVERSITY Global change is often perceived as human-induced modifications in climate. Indeed, human activities have undeniably [...]

WE PROPOSE A PARADIGM THAT ENHANCES HETEROGENEITY INSTEAD OF HOMOGENEITY TO PROMOTE BIOLOGICAL DIVERSITY AND WILDLIFE HABITAT ON RANGELANDS GRAZED BY LIVESTOCK Rangelands are the most common form of terrain [...]

A review of 43 habitat conservation plans reveals numerous ways to reduce uncertainty for landowners and imperiled species alike A town meeting in eastern Texas virtually erupts at the mention [...]

Abstract. Anthropogenic changes in temperature and stream flow, associated with watershed land use and climate change, are critical influences on the distribution and abundance of riverine fishes. To project the [...]

Abstract. Methods for predicting the ecological impacts of land use change on biodiversity and ecosystem function are needed to guide land planning and resource management decisions. This study explores the [...]