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This extensive revision of the first edition of People and the Land Through Time incorporates research over the last two decades to bring the field of historical ecology from an ecological perspective up to date. It emphasizes the use of new sources of data and interdisciplinary data analysis to interpret ecological processes in the past and their impacts on the present. It describes a diversity of past ecosystems and processes, with an emphasis on their effects on affect current ecosystem structure and function. This historical perspective highlights the varied and complex roles of indigenous people in historic ecosystems as well as the importance of past and present climatic fluctuations. The book begins with an introduction to the importance of history for ecological studies. The next three chapters explain methods and approaches to reconstructing the past, using both traditional and novel sources of data and analysis. The following five chapters discuss ways people have influenced natural systems, starting with the most primitive, manipulating fire, and proceeding through altering species ranges, hunting and gathering, agriculture and finally structuring landscapes through land surveys, trade and urbanization. Two chapters then deal with diversity, extinction and sustainability in a changing world. The final chapter specifically focuses on the importance of history in basic ecological studies, in conservation and in understanding the consequences of global change, using a variety of examples. Throughout, the emphasis is on the potential for evidence-based research in historical ecology, and the new frontiers in this exciting field.

This chapter considers movement of species over time. Many land managers and ecologists consider invasive species to be the most important factor in disrupting "natural" ecosystems today, at least in North America. This chapter takes a historical approach to the process of species range extensions beginning with changes in the absence of human vectors, then considering the specifically human role in disseminating species world-wide. Human-mediated species' range extensions are ancient in many parts of the world so that what we might think of as "natural" may also have a human aspect. Using examples of range extensions of plants, animals, and disease-causing organisms, the discussion offers cautionary tales of species that have been introduced on purpose or inadvertently and have later caused severe disruptions to native ecosystems, as well as more positive examples of cultural landscapes in which non-native species are fully integrated into diverse and functional ecosystems. Comparing change over time in species diversity and importance may show unexpected patterns, such as the increase in both native and non-native plant species at the same sites in England. Historical studies also indicate that removal of the exotics may not lead to reestablishment of the native flora. Integration of some non-native species into a new ecosystem may eventually be more or less complete.

This chapter introduces the use of historical documents and other forms of information that depend on written explanation, such as natural history collections and historical photographs. After a general explanation of the unique values of these data for establishing historical baselines and trajectories, it gives a brief introduction to the methods used to assess the validity of the sources, including consideration of various biases that are integral to written documents. These include a consideration of scale. The chapter then describes a variety of sources, including historical data, maps, photographs, government documents, and plant and animal collections, with examples of how each has been used to establish some condition or process in the past.

Using a wide variety of examples, this chapter emphasizes evidence that all landscapes and ecosystems today reflect not only climate change but also intensive and extensive past human impacts. They cannot be interpreted solely based on conditions evident today. The imprints of past human activities which can be obvious or subtle, must be unraveled for understanding the system today. Historical ecology integrates various drivers of change, and stability, using interdisciplinary methods, to provide a deeper understanding of structure and function today. Conservation seeks in some places to maintain ecosystems that have arisen over centuries or even millennia due to human impact, for example, ancient woodlands and upland meadows in Europe. In many parts of the world such ancient systems are reservoirs of high biodiversity. Historical research illuminates the historical factors that contribute to this diversity, assisting in planning for conservation. A major point is that ecologists are apt to make mistakes in interpreting patterns and processes as well as in conservation and restoration if they do not consider the history of sites, which provides evidence of past variability and of processes that have led to the current conditions of the system.

Species extinction leads to diversity in terms of number of species worldwide. Locally, however, immigration of species may at the same time in many areas increase the number of species, that is, the diversity. These contrasting processes of extinction and immigration have been accelerated by people over the millennia. This chapter discusses the causes and consequences of the processes over time, including examples from many habitats which demonstrate that trying to understand the causes and values of diversity in an ecosystem without analysis of its history can lead to erroneous conclusions. Several types of habitats where disturbance, often caused by people, increases and maintains diversity are analyzed from an historical perspective. Examples are also given of studies of past extinctions and their causation using models which lead to reinterpretation of the causes of the extinctions. Whether considering the early Holocene extinction of the megafauna of most continents the diversity of coppice woodlands in England, or the loss of thylacines and Tasmanian devils in Australia, this chapter illustrates that the relationship between cause and effect is almost always a complex, multifactorial one, and includes both human and non-human causation.

This chapter discusses the concept of sustainability using as a specific example concerns about the sustainability of oak-dominated forests in the northeastern United States. The discussion from the first edition is updated with current research, leading to the conclusion that climate is the most critical factor in determining species ranges even in human-dominated landscapes, and that fluctuations during the Holocene have been reflected not only in altered species composition of forests, but also in human populations and thus land use. At the same time, changes wrought by people have influenced decadal dynamics, such as secondary successional patterns, and often all but eliminated species within some plant communities, by land use change. Merely comparing present to inferred processes in the past misses vital factors in change; inference must be supported by historical data. Worldwide, droughts inferred from multi-proxy data can be correlated with declines in human populations as well as with changed vegetation, regardless of the complexity of the civilizations and agricultural systems. Managing systems for sustainability, requires consideration of legacies left by past land use.

This chapter shows how detailed historical ecological research indicates that the impacts of historical agriculture are more widespread than previously thought, and often more subtle. Even apparently obvious connections, such as that between nomadic grazing and erosion, are now being questioned by historical analyses. Agriculture has not resulted universally in decreased biodiversity; in fact, grazing over millennia has in places increased biodiversity. Historical agriculture is also being implicated in millennial scale increases in CO2 and CH4 in the atmosphere, the former from deforestation and fires and the latter from paddy rice agriculture starting five thousand years ago. The discovery of hidden field systems under mature temperate and tropical forests and grasslands in Europe and the Americas are allowing reassessment of the impact of prehistoric agricultural systems on soils, species diversity, landscape patterns, and climate. The concept of "landnam" episodes proposed by Iversen for northern Europe may be applicable much more broadly. This has major consequences for considering human impact on global environments.

This chapter treats a variety of human interactions with the land that trace their origins more to political and commercial drivers rather than directly to geology, topography, soils and local biota. Examples of land subdivisions are taken mostly from the United States, which illustrates a variety of land-use patterns that result from property surveys. Land hunger and government policies have also contributed to wars, which have altered landscapes. These have characterized the history of most parts of the world, having major repercussions on the environment as well as on people. Examples range over time and space. Industrialization increased the ability of people to travel and thus trade quickly over long distances thus intensifying and extending the impact of humans on the land, especially as industrialization further separated local land use from resource protection. Cities have flourished, often along trade routes, perhaps even before the development of agriculture Some all but disappeared, but all have had both local and regional effects on the land. Examples are discussed of effects both within cities today and resulting from cities that no longer exist.

This extensive revision of the first edition of People and the Land Through Time incorporates research over the last two decades to bring the field of historical ecology from an ecological perspective up to date. It emphasizes the use of new sources of data and interdisciplinary data analysis to interpret ecological processes in the past. It describes a diversity of past ecosystems, and how they affect current ecosystem structure and function as well as offering insight into current structure and process, and assisting in predicting the future. This historical perspective highlights the varied and complex roles of indigenous people in historic ecosystems and as well as the importance of past and present climatic fluctuations. The book begins with an introduction to the importance of history for ecological studies, and then has three chapters which explain methods and approaches to reconstructing the past, using both traditional and novel sources of data and analysis. The following five chapters discuss ways people have influenced natural systems, starting with the most primitive, manipulating fire, and proceeding through altering species ranges, hunting and gathering, agriculture and finally structuring landscapes through land surveys, trade and urbanization. Two chapters then deal with diversity, extinction and sustainability in a changing world. The final chapter integrates the rest of the book especially in terms of the importance of history in basic ecological studies, global change and understanding conservation. Throughout, the emphasis is on the potential for evidence-based research in historical ecology, and the new frontiers in this exciting field.

This chapter opens with a discussion naturally ignited fires and fire adaptations, which have evolved over millions of years. It then considers the role people have played over time in manipulating fire regimes, both locally and on a broad scale. Examples from diverse biomes such as the savannas and grasslands of South Africa and Madagascar, the forests of northern Europe and the grasslands and forests of North America provide evidence of the interactions between climate and human-set ignitions. The studies of the systems include analysis of a diverse range of evidence, including sediments, documents, and field evidence, analyzed using models that focus on patterns and processes of fire regimes under differing climates and human activities. The importance of perceptions of the role of fire is also discussed in terms of using fire for management, with examples of changes in attitude in North America from the 19th to the 21st centuries, which have led from seeing all fires as bad to valuing fire as a management tool. Analysis of the historical importance of human-set and natural fires has been critical to arriving at current management decisions.

There are many field techniques that take research beyond what can be found in written documents. Clues to the past are hidden in such subtle (and not so subtle) features as topographic modifications, soils, and tree trunks. Field studies search for evidence of conditions and for their resultant effects through a variety of techniques. Features may be evident from a ground survey, located precisely through GPS. Remote imaging, using a variety of techniques from simple aerial photography to lidar, reveal hidden patterns, that may then be studied on the ground. Archeological study relates the patterns found on the ground to human activities, as they have changed over time. Dendroecology interprets records left in tree rings. Some studies look at stands of different ages to study change over time, and long-term studies trace change in individual stands. In these field studies that look at the past, soil characteristics and materials hidden in the soil, such as DNA, stable isotopes and charcoal, can reveal details of past processes and species. These methods are illustrated with examples from a wide range of biomes.

People have always had to rely on hunting and gathering for food, fuel and shelter. The first evidence for possible major impact of these activities is the early Holocene extinction of most megafauna on all continents except Africa. Multidisciplinary historical research indicates that both climate and human impact interacted to cause these extinctions. This chapter also discusses historical records which have elucidated some of the long-term impacts of harvesting fish and other creatures of seas and estuaries on aspects such as population numbers, age structure, and species diversity of these organisms. On land, hunting has continued to affect many species. Agriculture, rather than decreasing the use of natural resources, has altered land use and increased demand so that the impact on natural resources has increased worldwide. Industrialization further accelerated this trend. Even those sites removed from active use by inclusion in preserves continue to change, in part because of a complex history of use before they were preserved. Understanding this history can help set appropriate goals for preservation as well as indications of management that may assist in evaluating changes.

Topography of a 2800 km 2 section of the U.S. Atlantic Coastal Plain and Piedmont is reconstructed at five times from the late Miocene to the Holocene. The reconstructions are based on mapping of fluvial, colluvial, and marginal-marine deposits that are dated by radiocarbon, palynostratigraphy, and correlation to adjacent glacial and marine units. Denudation rates and patterns are calculated by subtracting successive topographies, with 60 m horizontal resolution and 6 m vertical resolution. The overall late Miocene to Holocene denudation rate of 10 m/m.y. is similar to other estimates of long-term denudation in the region. The overall rate resolves spatially into a wide range of local rates, varying from a minimum of ∼0.2 m/m.y. on residual uplands to as high as 600 m/m.y. in glacially rerouted stream channels. The distribution of local rates shows that denudation is accomplished by stream incision in response to long-term glacio-eustatic decline, followed by slope retreat into residual uplands from the incised channels. Slope retreat replaces the uplands with pediments and straths. Pediment landforms and sediments, and observation of modern scarps and valley heads, indicate that groundwater seepage from the base of residual uplands is an important mechanism of slope retreat. This process is self-limiting because as the volume of residual upland is reduced, seepage diminishes and slope retreat slows until small residuals undergo little or no further reduction. Thus, relict topography is preserved even as most of the landscape actively erodes.

Palynological analyses of two sediment cores, one 2.4 m long from northern Delaware, dated about 16,300 to 14,70014C yr B.P., and one 1.8 m long from New Jersey just south of the Wisconsinan terminal moraine and dated about 13,600 to 12,50014C yr B.P., give the first detailed evidence of vegetation in this area during these periods. The overall assemblages are similar to each other, withPiceaandPinusdominating the arboreal pollen and Poaceae and Cyperaceae the herbaceous flora. Nonarboreal pollen contributes about 30–50% of the total, indicating a very open vegetation or a mix of forest patches and open areas. Especially in Delaware, there is a diversity of other herbaceous pollen, including members of the Asteraceae, Fabaceae, and Ranunculaceae. The assemblages do not resemble current North American tundra or boreal forest assemblages; rather, they resemble assemblages characteristic of tundra on recently exposed land surfaces north of the Wisconsinan terminal moraine. The persistence of the assemblages for 1500–2000 years in late-glacial time suggests stable and cold climate during this time of glacier retreat.

A survey was made of 37 dairy farms in Wirral, mid-Cheshire, mid-Somerset and Dyfed, Wales, to assess the incidence and prevalence of lameness in the cows between May 1989 and September 1991. The incidence was obtained from records made whenever a cow was examined for lameness or received preventive foot-trimming. The mean annual incidence was 54.6 new cases per 100 cows with a range from 10.7 to 170.1 and the mean values during summer and winter were 22.9 and 31.7, respectively. The prevalence of lameness was measured by regular visits at which locomotion was scored on a scale of 1 to 5, and the prevalence of lameness was calculated for each visit as the proportion of cows with scores of 3 or more. The mean annual prevalence over the whole period was 20.6 per cent with a range from 2.0 to 53.9 per cent for the 37 farms. The mean prevalences during summer and winter were 18.6 and 25.0 per cent, respectively. The prevalence measured at a single visit in midsummer or midwinter was significantly correlated with the mean prevalence over the whole corresponding period and may be useful as an assessment of the extent of lameness in a herd and the efficacy of control measures. There was evidence that training farmers to recognise early cases of lameness and request veterinary treatment resulted in a marked reduction in the duration of cases of lameness.

Soil water characteristic curves are a prerequisite for quantifying the field soil water balance and predicting water flow in unsaturated soils. The spatial variation of water retention in the root zone influences water availability for plants, evaporation, and fluxes of water and solutes through soils. The purpose of this study was to determine the ability of a popular model for the soil water retention function to describe the spatial variability of measured retention data and to investigate the application of a water content scaling theory to reduce the apparent spatial variation of soil water retention. Using a combination of Tempe cells and 1.5-MPa pressure plate extractors, we measured soil water retention at six pressure heads. In total, 281 undisturbed soil core samples were taken from the Ap horizon (0 to 17-cm depth increments) along an 80-m transect on a bare silt loam soil at 0.30-cm intervals. Sample statistics were calculated to identify outliers and erroneous data. A four-parameter retention model (θ s , θ r , α, n) was fitted to the data, and water content scale factors were also calculated. The soil water retention model was found to be extremely flexible in fitting the measured data. The parameters in the retention model showed a structured variance with a range of influence between 12 and 30. The number of parameters needed to characterize the field variability was 912 for the retention model. Scaling theory applied to the water retention data significantly reduced the apparent spatial variability. One scale factor also showed a structured variance, indicating a spatial correlation distance of greater than 30 m. Using the Akaike information criterion, we found that scaling theory could adequately represent the spatial variation in water retention with only 460 parameters. Sampling, calibration and/or experimental errors were thought to account for more than 50% of the total variability

A qualitative scoring method was devised to describe foot shape in dairy cattle, which relied solely on visual observations. Four independent trained observers used the method to assess the foot shape of 248 cows located on three farms on two different occasions, and the percentages of agreement and near-agreement for intra-observer and interobserver variation on scores for foot shape were calculated. Score assessment methods were suitable for describing features with a broad variation within one score value; reducing the number of observers did not improve best agreement between separate observations by more than 80 per cent.

The New Jersey Pine Barrens are an oasis of rare species, unique ecosystems and open space in the midst of the Boston to Washington megalopolis. Because this area has a long history of human exploitation and private land ownership direct purchase as a park is unfeasible and inappropriate. The alternative conservation strategy that has been adopted is to create a ‘green line’ park, the Pinelands National Reserve, in which all of the land included within the boundaries of the Reserve is subject to regulations on building and development, while some of the most critical areas are protected by purchase. Conservationists used the strong base of scientific knowledge of the area and theory to gain protection for fragile ecosystems. This use of emerging theory to protect parts of the landscape is an example of the kind of innovative planning that is necessary to protect land in areas where there is already much human impact and pressure for development.

Natural runoff plots on which maize was produced were laid out at Cedara on a well-drained clay loam Doveton soil and showed, over a six-year period, the benefits to be gained from adopting conservation tillage practices. The four tillage and crop utilization practices compared were: no-till with all crop residues retained; chisel ploughing after simulated light grazing (which left half of the crop residues on the surface); mouldboard ploughing in spring after simulated light grazing; and mouldboard ploughing in autumn after the removal of all plant residues. Mean annual soil loss and runoff (in parentheses) for the respective tillage practices were 0.41 (18 mm); 1.11 (25 mm); 3.01 (38 mm) and 5.91 (66 mm).

Landscapes must be understood as dynamic time-dependent entities rather than static associscapes, oral, written, (carto-)graphic and ecological sources can be used. Combinations of these sources usually provide reliable historical information, if based on a critical analysis of the quality and background of the data, including cross-checking information from the different data sources. The general public, planners, politicians, land managers, ecological modelers, and restoration ecologists are just some of the potential users of landscape history.

A survey of cubicles and indoor and outdoor walking surfaces on 37 farms served by four veterinary practices in Somerset, Cheshire, Wirral and west Wales was carried out in 1989 to 1991. A study of the space requirements of Friesian/Holstein cows at pasture showed that they required approximately 240 cm x 120 cm lying space and a further 60 cm lunging space for rising. By these standards, 87 per cent of the cubicles were too short and 50 per cent were too wide or too narrow. Over 1500 observations on cows lying down, rising and standing indicated that only 12 per cent of the cubicles permitted real freedom of movement; 91 per cent of top partition rails were judged to be too low and 70 per cent of bottom rails too low or too high. In addition, the kerb was very high in 76 per cent of the cubicles. As a result, 10 per cent of cows appeared moderately or severely restricted when lying down, 33 per cent when rising and 55 per cent when standing. Over 2000 cubicle beds were also studied; 75 per cent had a concrete base and of those, 63 per cent were judged to have too little bedding and 11 per cent next to none. Higher incidences and prevalences of lameness were associated with limited borrowing space (P

Astute observers have long recognized that human activities have indirect, unexpected, and often deleterious effects on natural systems. George Perkins Marsh was probably the first to consider explicitly the indirect and cumulative effects of human activities, observing in 1864 that “[w]e are never justified in assuming a force to be insignificant because its measure is unknown, or even because no physical effect can now be traced to its origin” (Marsh 1965:465). The critical importance of understanding the interconnections between human activities and the natural world is even greater today than it was in the mid-nineteenth century as the pace and pervasiveness of human influence intensifies. There are ever-increasing human activities with currently subtle but potentially devastating effects.

spp.), beech (Fagus grandifolia), and hemlock (Tusga canadensis) with consistent slopes for all three regions. The patterns fit well with colonial forest composition as inferred from regional pollen studies and with climatic preferences of the taxa, suggesting that these proprietor's data provide an accurate representation of forest composition. The same analyses were done with a subset of five towns where two sets of data were available: proprietor's data and road survey data. There were significant differences between the two data sets, with the road surveys not related to climatic gradients. We suggest that different types of survey records represent different aspects of forest composition, so that data from specialized surveys such as those for roads should be used only in spatially specific studies where the location of the surveys within a town can be taken into consideration.

Conditions just prior to field abandonment and the early stages of forest regeneration have residual effects on patterns of forest regeneration, but are often not available for study. The potential of pollen preserved in acidic soils to reconstruct land-use immediately before field abandonment was tested here by comparing known stand histories with analysis of pollen which had washed downward into the soil. Large amounts of Ambrosia in the soil pollen, accompanied by Asteraceae and Poaceae, indicated that a site was a plowed field prior to the start of forest regeneration. Abrupt shifts in proportions of Pinus and Quercus pollen correlated with known logging histories. Sites of unknown history included similar diversity in the proportions of nonarboreal pollen, and no evidence of logging. Proportions of tree taxa in soil pollen and vegetation surveys correlated only weakly. Soil pollen analysis, under appropriate conditions of pollen preservation, can provide evidence of major differences in site histories for which there is otherwise little evidence.

By the end of the nineteenth century foresters and others were beginning to realize that the forest resources of the United States were being rapidly depleted. In 1894 the New Jersey state legislature formally recognized the severity of the problem, noting that market control was providing inadequate protection for the state's natural resources. To establish a basis for state regulation the New Jersey legislature authorized the state geologist to conduct a survey "to ascertain the extent, character and location of the wild lands in [the] state which [were] suited for permanent occupation by forests rather than by agriculture." One aim of this survey was to determine "the advantages as regards the timber supply, water supply, scenery and

The historical evidence for the Indians' burning the forests of the northeastern United States is reevaluated. Of 35 documents that describe vegetation or Indian life in the 16th or 17th centuries, only half mention any use of fire except for cooking. Only six purportedly first—hand accounts might refer to purposeful, widespread, and frequent use of fire. These six are all consistent with use of fire only locally near camps or villages, or with accidentally escaped fires. It is concluded that the frequent use of fires by the Indians to burn the forests was probably at most a local occurrence. The Indians' presence in the region and their use of fire for many purposes did, however, increase the frequency of fires above the low levels caused by lightning, and thus had some effect on the vegetation; for example, grasses characterized the ground cover at small, local, frequently burned sites.

Simulated rainfall, using low conductivity water, was applied at an intensity of 63 mm h−1 to a field soil of the Doveton series (a kaolinitic, sesquioxidic clay soil at Cedara in Natal, recently cultivated out of pasture) after pre-treatment of the scarified soil surface with a mulch of maize stover, 200 kg ha−1 of sodium hexametaphosphate (applied in solution), or 10 000 kg ha−1 of industrial phosphogypsum. The decline in infiltration rate with cumulative rainfall was accelerated by the hexametaphosphate (final infiltration rate after 126 mm rain was 27 mm h−1 compared with 42 mm h−1 for the untreated control) and retarded by the gypsum (final IR=47 mm h−1) and mulch (53 mm h−1) treatments. After 60 mm of a second rain, final IR was 26 (control), 24 (hexametaphosphate), 35 (gypsum) and 26 mm h−1 (mulch). Laboratory-simulated rain produced a similar result with gypsum to that found in the field. Ultrasonic treatment of suspensions of the same soil showed (i) that with decreasing aggregate size, an increa...

The natural vegetation and spoils of two abandoned, unreclaimed coal mines in the Mountain Park area were studied quantitatively in 34 stands. After 26 years of abandonment the vegetation of both Townsite and West Mine was sparse. Total plant cover was usually

Perfectly spherical sand to clay size particles composed of magnetite occur in a wide variety of environments. Within the greater New York City area such spherules are found in smoke-stack filtrate, urban-air filtrate, ditritus collected from highway surfaces, lake sediments, marsh sediments, and in beach sands. The abundance of spherules in such environments diminishes away from industrial centers. The abundance of magnetite spherules in core samples of lake and marsh sediment decreases sharply near the palynologically determined stratigraphic boundary separating sediments deposited before the area was settled and industrialized from sediments deposited afterward. Their abundance in samples of deep ocean-floor sediment also drops off sharply within the upper 10 cm of core. The spheru es become rare to absent below this depth. We conclude that the great majority of magnetic spherules presently accumulating in sediments are of industrial origin, while we recognize the existence of spherules of probable extraterrestrial origin in ancient sediments. The ease of identification and recovery of magnetite spherules from sediments facilitates their use as indicators of probable post-industrial age.

Aim This study compares human impacts and forest ecosystem response across geographical regions. Such a comparison allows us to evaluate the relationship between regional changes in forest composition and regional patterns of human activity. Location Four study areas in the north-eastern USA were investigated, two of which were dominated by oak-pine forests at the time of European settlement (Central Massachusetts, MA; Pike County, PA), and two of which were dominated by beech and hemlock (South Berkshire, MA; Wayne County, PA). Methods Trees recorded in early land survey records were compiled and compared with data on modern forest composition obtained from recent forest inventories. To assess the similarity of the four regions with regard to species composition, Euclidean Distances (ED) were calculated between the colonial and modern forest composition for each of the four regions. Information about the history of human impacts in the four study regions was used to interpret the changes in forest composition. Results General changes in forest composition through the historical period include a decline in beech, hemlock and chestnut, and an increase in maple and birch. Changes in pine and oak were minor by comparison. Supraregional human impacts are generally linked with supraregional trends in species composition, whereas regional patterns of land use caused regional patterns of change in species composition. Main conclusions These results suggest that human activities do not necessarily lead to more similar species composition between regions, especially if these activities show clear spatial patterns at about the same resolution that species composition is evaluated. Comparing species-specific changes in forest composition with species-specific human activities on the same spatial scale is crucial in order to evaluate human impacts on ecosystems and to make more robust generalizations about the temporal dynamics of landscapes.