Changes In Land Management Practices Research Articles

Population Genetic Structure of California Hazelnut, An Important Food Source for People in Quiroste Valley in the Late Holocene

California hazelnuts (Corylus cornuta var. californica) are abundant in the archaeological record of site CA-SMA-113 in Quiroste Valley Cultural Preserve, and hazel management on the Central Coast was recorded in late 18th century Spanish accounts. However, this species is currently absent from Quiroste Valley proper and rare in the watershed, though it is locally common elsewhere in the Santa Cruz Mountains. Because high California hazelnut abundance is associated with frequent fire regimes, we believe that its current low abundance could be due to fire suppression enforced in the region for the past two hundred years. We sequenced nuclear microsatellites from ten populations of California hazelnuts to test the hypothesis that this species has experienced demographic changes in response to changing climate and land management practices. We found that all populations exhibited high levels of genetic variation and negative population growth consistent with large population sizes in the past with some decline over time. We also found subtle patterns of geographic structure suggesting that Quiroste Valley and neighboring Butano may have been important refugia habitats during past climate warming events. These results provide an important foundation demonstrating that population genetic approaches can be applied to eco-archaeological research on indigenous landscape management and set the stage for future work using genetics to reveal further details of the demographic history of Quiroste Valley hazelnut populations.

Water Quality Degradation of Coastal Waterways in the Wet Tropics, Australia

The Wet Tropics region of north Queensland has outstanding environmental values, contains the highest biological diversity in Australia, and borders the Great Barrier Reef. Comparable to other tropical areas worldwide, increasing urban and agricultural development in the Wet Tropics has caused concerns with respect to ecosystem degradation due to poor water quality in freshwater reaches and marine environments. Key issues currently identified in the Wet Tropics include erosion and subsequent stream turbidity and sedimentation, nutrients from erosion and fertiliser use and pesticide residue contamination. Issues such as reduced dissolved oxygen, acid sulfate soil runoff, and biological factors such as weed infestation, reduced and degraded riparian vegetation condition, and flow modification have also been identified. These issues mainly arise from agricultural activities with lesser effects from urban development. Management of pollution to improve in-stream water quality requires a long-term monitoring program to characterize water quality conditions over different flows and seasons. This type of monitoring program is underway; however, the focus is on the Great Barrier Reef and does not fully consider freshwater ecosystem health. Another major issue is the lack of a fully developed conceptual framework that links changed land use to water quality and subsequently to aquatic ecosystem health. In this paper, we establish the current level of water quality knowledge in the Wet Tropics while outlining a conceptual framework connecting changing land management practices and their effects to water quality and to ecosystem health.

Managing carbon in a multiple use world: The implications of land-use decision context for carbon management

Human land use contributes significantly to the growth of greenhouse gases in the atmosphere. Changes in land management practices have been proposed as a critical and cost-effective mechanism for reducing greenhouse gas emissions and promoting the storage of additional carbon in vegetation and soils. However many discussions of the potential for land use to mitigate climate change only take into account biophysical factors such as vegetation and land cover and neglect how the agency of land owners themselves affects whether additional carbon storage can be achieved. Unlike many potential REDD opportunities in developing countries, land management in the U.S. to enhance carbon sequestration would occur against a backdrop of clearly defined, legally enforceable land ownership. In addition, more than a third of the land surface in the U.S. is managed by federal agencies who operate under legal guidelines for multiple use and is subject to demands from multiple constituencies. We set out to investigate how the goal of enhancing carbon sequestration through land use is perceived or implemented in one region of the U.S., and how this goal might intersect the existing drivers and incentives for public and private land use decision making. We conducted a case study through interviews of the major categories of landowners in the state of Colorado, which represents a mixture of public and privately held lands. By analyzing trends in interview responses across categories, we found that managing for carbon is currently a fairly low priority and we identify several barriers to more widespread consideration of carbon as a management priority including competing objectives, limited resources, lack of information, negative perceptions of offsetting and lack of a sufficient policy signal. We suggest four avenues for enhancing the potential for carbon to be managed through land use including clarifying mandates for public lands, providing compelling incentives for private landowners, improving understanding of the co-benefits and tradeoffs of managing for carbon, and creating more usable science to support decision making.

Restoration and management of machair grassland for the conservation of bumblebees

Machair is a grassland habitat that supports nationally rare species including the bumblebee species Bombus distinguendus and Bombus muscorum. Changes in land management practices have resulted in a loss of floral diversity in some areas, reducing the availability of bumblebee foraging resources. In order to determine the most effective way of increasing forage plant availability on degraded machair, a restoration trial was established in western Scotland and comprised four seed mixes and a fallow treatment. Treatments were monitored over 3 years in order to compare the relative abundance of bumblebees and their forage plants. Two mixes contained wildflower species; one mix is currently used to create bird and bee foraging habitat on nature reserves and the fourth is a commercially available grass mix. There was little variation in inflorescence and bumblebee abundance between treatments early on but marked differences emerged later in the season in all 3 years. By the end of the monitoring period, the wildflower treatments contained between four and eighteen times more inflorescences than other treatment types. Similar trends were observed in bumblebee abundances. Some of the rarest bumblebee species exist primarily in areas that have largely escaped agricultural intensification. In these areas it is important that habitat management is specifically targeted and translated into appropriate agri-environment schemes. We suggest that the most effective method for restoring bumblebee forage plants on machair is to sow wildflower-rich seed mixes and this should be combined with late cutting and winter grazing practices to maintain sward diversity over time.

Differences in wildfires among ecoregions and land management agencies in the Sierra Nevada region, California, USA

Recent research has indicated that in most of the western United States, fire size is increasing, large fires are becoming more frequent, and in at least some locations percentage of high‐severity fire is also increasing. These changes in the contemporary fire regime are largely attributed to both changing climate and land management practices, including suppression of fires and past timber harvesting, over the last century. Fire management, including suppression and using wildfire for resource benefits, varies among federal land management agencies, yet no published studies have directly compared fire statistics between federal land management agencies in our study area. The primary response to wildfire on Forest Service areas is immediate suppression, while the National Park Service is more likely to use wildfire for resource benefits. We use fire perimeters and satellite‐derived estimates of fire severity to compare fire statistics for wildfires (fire size, percentage of high‐severity fire and high‐severity patch size) among ecoregions, forest types, and land management agencies 1984–2009 in the Sierra Nevada, Southern Cascades, and Modoc Plateau of California, USA. High‐severity patch size and percentage of high‐severity fire, regardless of forest type, were less (P < 0.05) in Yosemite National Park than on Forest Service lands. Yosemite fires were smaller on average than fires on Forest Service lands on the east side of the Sierra Nevada, southern Cascades and Modoc Plateau. Depending upon whether fires that crossed boundaries were included or not, mean size of Yosemite fires was either smaller or not significantly different from Forest Service fires on the west side of the Sierra Nevada. Even under current conditions, it appears that fire management practices that emulate those used in Yosemite could moderate effects of past land management, restoring and helping to maintain old forest conditions within the greater Sierra Nevada region, including the southern Cascades and Modoc Plateau.

Quantifying the Stock of Soil Organic Carbon using Multiple Regression Model in a Fallow Vegetation, Southern Nigeria

Identifying ecological variables that explain significant variation in the stock of carbon is indeed one way of sustaining its concentration in the soil. The stepwise multiple regression model was employed to identify ecological variables that explained significant variation of carbon in fallow soils. Using fallow genealogical cycles of 1st, 2nd, 3rd, 4th and 5th generations, soil and vegetation variables from 30 sampling plots were collected and subjected to linear regression analysis. The analysis generated three predictive models. The first and second models significantly (p<0.01) explained 78% (R2 = 0.78) and 87% (R2 = 0.87) of the variability in soil organic carbon (SOC), while the third (full) model significantly (p<0.01) explained 89% in the variability of carbon stock (R2 = 0.89) with vegetation cover, available phosphorus and total nitrogen being the most significant predictor variables. The full model was upheld because it identified three significant ecological variables that explained increased variability in the stock of SOC. The study suggested that management of the ecological variables identified in the full model which indeed were associated with the abundance of woody and herbaceous vegetation would not only increase the stock of SOC in the soil, but reduced its concentration in the atmosphere. For this to be feasible mostly in the present changing climate, healthy forest and land management practices, such as the creation of vegetal buffer zones around farmlands, zero-tillage practice, mulching, retaining of forest slash and crop residues, fertilizer application, elongation of fallow periods, and tree planting initiatives in degraded ecosystems were encouraged.Keywords: Stepwise Regression, SOC, Healthy Forest and Management Practices Fallow Genealogy,Woody Perennial Tree Species, Fallow Elongation

The dynamics of soil redistribution and the implications for soil organic carbon accounting in agricultural south‐eastern Australia

AbstractAnthropogenically induced change in soil redistribution plays an important role in the soil organic carbon (SOC) budget. Uncertainty of its impact is large because of the dearth of recent soil redistribution estimates concomitant with changing land use and management practices. An Australian national survey used the artificial radionuclide caesium‐137 (137Cs) to estimate net (1950s–1990) soil redistribution. South‐eastern Australia showed a median net soil loss of 9.7 t ha−1 yr−1. We resurveyed the region using the same 137Cs technique and found a median net (1990–2010) soil gain of 3.9 t ha−1 yr−1 with an interquartile range from −1.6 t ha−1 yr−1 to +10.7 t ha−1 yr−1. Despite this variation, soil erosion across the region has declined as a likely consequence of the widespread adoption of soil conservation measures over the last ca 30 years. The implication of omitted soil redistribution dynamics in SOC accounting is to increase uncertainty and diminish its accuracy.

Designing watershed programs to pay farmers for water quality services: Case studies of Munich and New York City

While preserving water quality by contracting with farmers has been examined previously, we analyze these arrangements from a different perspective. This study uses a transaction cost framework, in conjunction with detailed case studies of two water quality payment schemes, to examine factors that increase and decrease transaction costs in order to improve policy choice as well as policy design and implementation. In both the Munich and New York City cases, agreements with farmers to change land management practices resolved the water quality problems. In Munich, factors including lack of rural/urban antipathy, homogeneous land use, utilization of well-developed organic standards, and strong demand for organic products decreased transaction costs. Using existing organic institutions addressed a range of environmental issues simultaneously. Factors that decreased transaction costs in both cases included: highly sensitive land was purchased outright and the existence of one large “buyer”. Adequate lead time and flexibility of water quality regulations allowed negotiation and development of the watershed programs. Tourism and eco-labels allow urban residents to become aware of the agricultural production practices that affect their water supply. We conclude with recommendations based on the experiences of these cities, both of which have been proposed as models for other schemes.

Causes of spring vegetation growth trends in the northern mid–high latitudes from 1982 to 2004

The Community Land Model version 4 (CLM4) is applied to explore the spatial–temporal patterns of spring (April–May) vegetation growth trends over the northern mid–high latitudes (NMH) (>25°N) between 1982 and 2004. During the spring season through the 23 yr period, both the satellite-derived and simulated normalized difference vegetation index (NDVI) anomalies show a statistically significant correlation and an overall greening trend within the study area. Consistently with the observed NDVI–temperature relation, the CLM4 NDVI shows a significant positive association with the spring temperature anomaly for the NMH, North America and Eurasia. Large study areas experience temperature discontinuity associated with contrasting NDVI trends. Before and after the turning point (TP) of the temperature trends, climatic variability plays a dominant role, while the other environmental factors exert minor effects on the NDVI tendencies. Simulated vegetation growth is broadly stimulated by the increasing atmospheric CO2. Trends show that nitrogen deposition increases NDVI mostly in southeastern China, and decreases NDVI mainly in western Russia after the temperature TP. Furthermore, land use-induced NDVI trends vary roughly with the respective changes in land management practices (crop areas and forest coverage). Our results highlight how non-climatic factors mitigate or exacerbate the impact of temperature on spring vegetation growth, particularly across regions with intensive human activity.

Trends in Snag Populations in Drought-Stressed Mixed-Conifer and Ponderosa Pine Forests (1997–2007)

Snags provide important biological legacies, resources for numerous species of native wildlife, and contribute to decay dynamics and ecological processes in forested ecosystems. We monitored trends in snag populations from 1997 to 2007 in drought-stressed mixed-conifer and ponderosa pine (Pinus ponderosaDougl.exLaws) forests, northern Arizona. Median snag density increased by 75 and 90% in mixed-conifer and ponderosa pine forests, respectively, over this time period. Increased snag density was driven primarily by a large pulse in drought-mediated tree mortality from 2002 to 2007, following a smaller pulse from 1997 to 2002. Decay-class composition and size-class composition of snag populations changed in both forest types, and species composition changed in mixed-conifer forest. Increases in snag abundance may benefit some species of native wildlife in the short-term by providing increased foraging and nesting resources, but these increases may be unsustainable in the long term. Observed changes in snag recruitment and fall rates during the study illustrate the difficulty involved in modeling dynamics of those populations in an era of climate change and changing land management practices.

Climate-change impact assessment using GIS-based hydrological modelling

A GIS-based Soil and Water Assessment Tool (SWAT) model is used to assess the impacts of climate change on the hydrological regime of the Cauvery river basin. First, the impact of changes in land-management practices on water availability under present conditions is modelled. Then, the same analysis is carried out under the future climatic scenarios. Finally, annual and monthly precipitation variability is compared under present, as well as future, climate-change scenarios. The results indicate an intensification of the hydrological cycle in the future climate-change scenario that appears to be significant on an annual basis.

Nitrate transport modeling to evaluate source water protection scenarios for a municipal well in an agricultural area

Fertilizers that are spread on agricultural fields can leach into aquifers and contaminate groundwater sources for drinking water particularly with nitrate. Modeling this phenomenon can help in evaluating the impact of current or future agricultural practices on nitrate content within an aquifer. The three-dimensional Water flow and Nitrate transport Global Model ( WNGM), that was previously developed and applied to a well-capture zone, is actually used to simulate future land management scenarios over the same zone. The studied area is located in a region with intensive agricultural practice in Southern Québec (Canada). The sandy unconfined aquifer underlying the agricultural fields is highly vulnerable to nitrate contamination from ground surface and nitrate concentrations around critical threshold of 45 mg NO 3 - /L were observed in the municipal well. Using the calibrated WNGM, a number of land management scenarios were simulated in order to predict future trends of nitrate concentrations in the pumping well from 2008 through 2040 that could be induced by changes in land management practices over this well-capture zone. More specifically, these scenarios simulate implementation of improved or ideal agricultural practices within the agricultural portion of the well-capture zone, and modification of the pumping rate at the municipal well. The results show how a decrease and stabilization of nitrate concentration should occur at the municipal well after a period varying from 5 to 30 years depending on the implemented agricultural modifications. It is also shown that, in this particular case, an increase of the pumping rate at the municipal well from 700 to 2800 m 3/d would lead to an increase of the well-capture zone from 0.8 to 2.5 km 2 and to a decrease of nitrate concentrations at the municipal well from 43 to 34 mg NO 3 - /L. Furthermore, it is predicted that application of improved agricultural practices in the vicinity of this municipal well could lead to a reduction of nitrate concentrations at the well of about 8 mg NO 3 - /L.

Agriculture‐Related Trends in Groundwater Quality of the Glacial Deposits Aquifer, Central Wisconsin

Measuring and understanding trends in groundwater quality is necessary for determining whether changes in land-management practices have an effect on groundwater quality. This paper describes an approach that was used to measure and understand trends using data from two groundwater studies conducted in central Wisconsin as part of the USGS NAWQA program. One of the key components of this approach, determining the age of sampled groundwater, gave a temporal component to the snapshots of water quality that were obtained through synoptic-sampling efforts. This approach can be used at other locations where groundwater quality data are collected, groundwater age can be determined, and associated temporal data are available. Results of these studies indicate measured concentrations of nitrate and atrazine plus deethylatrazine were correlated to historical patterns of fertilizer and atrazine use. Concentrations of nitrate in groundwater have increased over time; concentrations of atrazine plus deethylatrazine increased and then decreased. Concentrations of nitrate also were correlated to screen depth below the water level and concentrations of dissolved O(2); concentrations of atrazine plus deethylatrazine were correlated to dissolved O(2) and annual precipitation. To measure trends in concentrations of atrazine plus deethylatrazine, the data, collected over a near-decadal period, were adjusted to account for changes in laboratory-reporting levels and analytical recoveries. Only after accounting for these changes was it apparent that the median concentrations of atrazine plus deethylatrazine decreased over the near-decadal interval between sampling efforts.

Parameter and input data uncertainty estimation for the assessment of long-term soil organic carbon dynamics

The use of integrated soil organic matter (SOM) models to assess SOM dynamics under climate change, land use change and different land management practices require a quantification of uncertainties and key sensitive factors related to the respective modelling framework. Most uncertainty studies hereby focus on model parameter uncertainty, neglecting other sources like input data derived uncertainties, and spatial and temporal properties of uncertainty. Sources of uncertainties assessed in this study stem from uncertainties in model parameterisation and from uncertainties in model input data (climate, soil data, and land management assumptions). Thereby, Monte Carlo based global sensitivity and uncertainty analysis using a latin hypercube stratified sampling technique was applied to derive plot scale (focusing on temporal propagation) and river basin scale propagation of uncertainty for long-term soil organic carbon (SOC) dynamics. The model used is the eco-hydrological river basin model SWIM (Soil and Water Integrated Model), which has been extended by a process-based multi-compartment model for SOM turnover. Results obtained by this study can be transferred and used in other simulation models of this kind. Uncertainties resulting from all input factors used (model parameters + model input data) show a coefficient of variation between 5.1 and 6.7% and accounted for ± 0.065 to ± 0.3% soil carbon content (0.06–0.15 t C ha −1 yr −1). Parameter derived uncertainty contributed most to overall uncertainty. Concerning input data contributions, uncertainties stemming from soil and climate input data variations are striking. At the river basin scale, cropland and forest ecosystems, loess and gleyic soils possess the highest degree of uncertainty. Quantified magnitudes of uncertainty stemming from the examined sources vary temporally and spatially due to specific natural settings (e.g. climate, land use and soil properties) and deliver useful information for interpreting simulation results on long-term soil organic carbon dynamics under environmental change. Derived from this analysis, key sensitive model parameters and interactions between them were identified: the mineralization rate coefficient, the carbon use efficiency parameter (synthesis coefficient) along with parameters determining the soil temperature influence on SOM turnover (mainly Q10 value) and the soil input related data ( soil bulk density and initial soil C content) introduced the highest degree of model uncertainty. The here gained information can be transferred to other process-based SOM turnover models to consider stronger most crucial parameters introducing highest uncertainty contribution to soil C storage assessment under changing environmental conditions.

Geoscientific land management planning in salt-affected areas

.Over the last twenty years, farmers in Western Australia have begun to change land management practices to minimise the effects of salinity to agricultural land. A farm plan is often used as a guide to implement changes. Most plans are based on minimal data and an understanding of only surface water flow. Thus farm plans do not effectively address the processes that lead to land salinisation.A project at Broomehill in the south-west of Western Australia applied an approach using a large suite of geospatial data that measured surface and subsurface characteristics of the regolith. In addition, other data were acquired, such as information about the climate and the agricultural history. Fundamental to the approach was the collection of airborne geophysical data over the study area. This included radiometric data reflecting soils, magnetic data reflecting bedrock geology, and SALTMAP electromagnetic data reflecting regolith thickness and conductivity. When interpreted, these datasets added paddock-scale information of geology and hydrogeology to the other datasets, in order to make on-farm and in-paddock decisions relating directly to the mechanisms driving the salinising process. The location and design of surface-water management structures such as grade banks and seepage interceptor banks was significantly influenced by the information derived from the airborne geophysical data. To evaluate the effectiveness of this planning, one whole-farm plan has been monitored by the Department of Agriculture and the farmer since 1996. The implemented plan shows a positive cost–benefit ratio, and the farm is now in the top 5% of farms in its regional productivity benchmarking group.The main influence of the airborne geophysical data on the farm plan was on the location of earthworks and revegetation proposals. There had to be a hydrological or hydrogeological justification, based on the site-specific data, for any infrastructure proposal. This approach reduced the spatial density of proposed works compared to other farm plans not guided by site-specific hydrogeological information.

EFFECTS OF RANGELAND MANAGEMENT ON COMMUNITY DYNAMICS OF THE HERPETOFAUNA OF THE TALLGRASS PRAIRIE

The Flint Hills of Kansas and Oklahoma are the largest remaining tracts of tallgrass prairie in North America. This area has undergone major changes in land management practices in the past 30 years. Traditional season-long cattle stocking with variable burn schedules has diversified to include intensive-early cattle stocking accompanied by annual burning. To understand how different land management practices affect the herpetofauna of a tallgrass prairie, we used mark-recapture statistics to analyze herpetofaunal community dynamics. We analyzed survey data collected over a 15-year time span (1989-2003) from a rangeland site in Cowley County, KS, USA. A modified Jolly-Seber open population model, POPAN-5, was used to estimate four community parameters: probability of species loss (w9), probability of detection (p), probability of entry (Pent), and species richness (N). The top models included burn status as a covariate for species loss rate, while cattle stocking received moderate support as a covariate. Rates of species loss were higher during burn years (w 95 0.04, 95% CI: 0.02 to 0.08) than nonburn years (w 95 0.00, 95% CI: 0.00 to 0.01). Analysis of the impacts of different management practices was difficult due to confounding effects of changes in both burning and grazing. Declines in species richness tended to be steepest during a period of season-long stocking, but results were not statistically significant. Though our limited data set does not allow us to draw strong conclusions on the effects of land management on herpetofaunal populations, the mark- recapture models illustrated in our study should prove to be a valuable tool in future analyses of similar data. THE TALLGRASS prairie has been reduced to less than five percent of its pre-European settlement extent, making it the most heavily impacted ecosystem in North America (Sam- son and Knopf, 1994). The largest contiguous section of remaining tallgrass prairie occurs in the Flint Hills of northern Oklahoma and Kansas (Knapp and Seastedt, 1998). Much of this region is unsuitable for row-crop agricul- ture because shallow soils are associated with limestone bedrock. However, the Flint Hills provide extensive rangeland for cattle. Much of the rangeland experienced a marked change in land management in the early 1980s. Traditionally, ranchers practiced sea- son-long cattle stocking, which allowed a lim- ited number of cattle to graze year-round, accompanied by rotation of burned and unburned areas every 2-3 years. Under in- tensive-early stocking, cattle stocking rates were roughly double that of the previous practice for only 90-120 days in the growing season with annual spring burns, which in-

Changing land management practices and vegetation on the Central Plateau of Burkina Faso (1968–2002)

In the early 1980s, the situation on the northern part of the Central Plateau of Burkina Faso was characterized by expanding cultivation on lands marginal to agriculture, declining rainfall, low and declining cereal yields, disappearing and impoverishing vegetation, falling ground-water levels and strong outmigration. This crisis situation provoked two reactions. Farmers, as well as technicians working for non-governmental organizations, started to experiment in improving soil and water conservation (SWC) techniques. When these experiments proved successful, donor agencies rapidly designed SWC projects based on simple, effective techniques acceptable to farmers. A study looked at the impact of SWC investments in nine villages and identified a number of major impacts, including: significant increases in millet and sorghum yields since the mid-1980s, cultivated fields treated with SWC techniques have more trees than 10–15 years ago, but the vegetation on most of the non-cultivated areas continues to degrade, greater availability of forage for livestock, increased investment in livestock by men and women and a beginning change in livestock management from extensive to semi-intensive methods, improved soil fertility management by farmers, locally rising ground-water tables, a decrease in outmigration and a significant reduction in rural poverty. Finally, data are presented on the evolution of land use in three villages between 1968 and 2002.

VEGETATION DYNAMICS UNDER FIRE EXCLUSION AND LOGGING IN A ROCKY MOUNTAIN WATERSHED, 1856–1996

How have changes in land management practices affected vegetation patterns in the greater Yellowstone ecosystem? This question led us to develop a deterministic, successional, vegetation model to “turn back the clock” on a study area and assess how patterns in vegetation cover type and structure have changed through different periods of management. Our modeling spanned the closing decades of use by Native Americans, subsequent Euro-American settlement, and associated indirect methods of fire suppression, and more recent practices of fire exclusion and timber harvest. Model results were striking, indicating that the primary forest dynamic in the study area is not fragmentation of conifer forest by logging, but the transition from a fire-driven mosaic of grassland, shrubland, broadleaf forest, and mixed forest communities to a conifer-dominated landscape. Projections for conifer-dominated stands showed an increase in areal coverage from 15% of the study area in the mid-1800s to ∼50% by the mid-1990s. During...

Habitat associations of breeding Meadow Pipits Anthus pratensis in the British uplands

Habitat associations of Meadow Pipits breeding in British upland 1 km and 10 km squares were investigated using data from the British Trust for Ornithology's (BTO) Breeding Bird Survey (BBS, 1994–97), The New Atlas of Breeding Birds in Britain and Ireland 1988–1991 and habitat data from the Institute of Terrestrial Ecology's (ITE) Land Cover Survey (1994). Meadow Pipit density was highest in 200 m sections of BBS 1 km transects containing unenclosed grass moor, heather and bog, but there was no difference in Meadow Pipit density between these habitat types. Meadow Pipit density (number of individuals per 1 km square) increased with heather cover up to about 7.5 200 m sections (of ten per 1 km square) of heather, but fell thereafter. There was a positive association between Meadow Pipit density and the extent of grass moor cover. The ITE Land Cover data gave results that were consistent with the BBS habitat data at both the 1 km and 10 km square scale. There was a non-linear relationship between hill grass cover and Meadow Pipit abundance, which reached a maximum when hill grass covered between 40%and 60% of a square. Our results suggest that a mosaic of heather, bog and grassland may be the optimum habitat for Meadow Pipits. Recent changes in land management practices may have led to the disappearance or degradation of these mosaics in some areas. Meadow Pipits are widespread and easily counted. We suggest that this species might be a useful bioindicator of changes in heather and grassland ratios that result from land management practices such as grazing and rotational burning, though further research is required.

Numbers and distribution of Northern Lapwings Vanellus vanellus breeding in England and Wales in 1998

This paper presents the results of the BTO/RSPB survey of breeding Northern Lapwings Vanellus vanellus in England and Wales carried out in 1998. Numbers of breeding Lapwings and land-use types were recorded by volunteers in 1312 randomly selected tetrads using identical methods to those adopted in a previous survey in 1987. The results suggest a population of 62 923 breeding pairs (95% confidence intervals 55 268 to 74 499), representing a 49% decline in 11 years. The declines were greatest in southwest England and Wales, resulting in a marked contraction in range. Both arable and pastoral farmland was found to be important for Lapwings, highlighting their vulnerability to changes in a range of agricultural systems. Recent major changes in land management practices, including the switch from spring to autumn sowing and the conversion of rough to intensively managed, improved grassland is likely to have reduced both the area and the suitability of these habitats for Lapwings. Grassland within arable areas is known to provide important chick rearing habitat, and spring tillage with adjacent grassland was significantly more likely to hold Lapwings than spring tillage that did not abut grass fields. The prevalence of grass and spring tillage fields in close proximity has declined in recent years with the loss of traditional mixed farming and the polarization of pastoral systems in the west of Britain and arable in the east. The implications of these results for the conservation of Lapwings are discussed and it is recommended that, in the light of the scale of the decline recorded, Lapwings should be afforded much higher conservation priority in Britain than they are at present. The range contraction has resulted in high numbers being concentrated on reserves, highlighting the importance of sensitive management of these areas for this species. However, wider countryside measures should also be considered, such as specific options within agri-environment schemes, designed to enhance farmland habitats for Lapwings.