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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. 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.

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).

Information from 37 dairy farms, in four regions of England and Wales provided data on 8991 lesions and the preventive trimming of 4837 cows' feet., American Association of Bovine Practitioners Proceedings of the Annual Conference, 1996

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...