The North American mid‐continent population of Lesser snow geese (Chen caerulescens caerulescens L.) has increased by ca. 7% per year, largely as a result of geese feeding on agricultural crops in winter and on migration. We describe the long‐term effects of increasing numbers of geese at an arctic breeding ground (La Pérouse Bay, Manitoba) on intertidal salt‐marsh vegetation. Between 1985 and 1999 goose grubbing caused considerable loss of graminoid vegetation along transects in intertidal marshes. Loss of vegetation led to bare sediment with a plant cover of less than 2%. Changes in vegetation could not be described by simple linear, geometric or exponential functions; most losses occurred between 1988 and 1990 and losses were staggered in time between individual transects, some of which had all vegetation removed.

Between 1979 and 1999 the standing crop in July in remaining intact heavily‐grazed swards of Puccinellia phryganodes and Carex subspathacea fell from 40–60 g m⁻² to 20–30 g m⁻². Intense grazing on remaining patches of sward has restricted growth of these clonal forage plants and hypersalinity of bare sediments has precluded re‐establishment of vegetation. Between 1989 and 1993 numbers of faecal droppings in grazed plots reached maximum values of 15–22 droppings m⁻² wk ⁻¹. Since then peak values have remained at less than 13 droppings m ⁻² wk ⁻¹. The loss of vegetation and changes in soil conditions have resulted in the establishment of an alternative stable state (hypersaline bare sediment).

Nomenclature: Porsild & Cody (1980).

In order to restore natural salt marsh in a 460‐ha nature reserve established in man‐made salt marsh in the Dollard estuary, The Netherlands, the artificial drainage system was neglected and cattle grazing reduced. Vegetation changes were traced through two vegetation surveys and monitoring of permanent plots over 15 yr after the management had been changed. Exclosure experiments were started to distinguish grazing effects from effects of increased soil waterlogging caused by the neglect of the drainage system.

Both vegetation surveys and permanent plots demonstrated a dichotomy in vegetation succession. The incidence of secondary pioneer vegetation dominated by Salicornia spp. and Suaeda maritima increased from 0 to 20%, whereas the late‐successional (Phragmites australis) vegetation from 10 to 15%. Grazing intensity decreased towards the sea. The grazed area contracted landward, which allowed vegetation dominated by tall species to increase seaward.

Grazing and increased waterlogging interacted in several ways. The impact of trampling increased, and in the intensively grazed parts soil salinity increased. This can probably be explained by low vegetation cover in spring.

Framework Ordination, an indirect‐gradient‐analysis technique, was used to infer the importance of environmental factors in influencing changes in species composition. Many changes were positively or negatively correlated with soil aeration and soil salinity, whereas elevation was of minor importance. Grazing accounted for only a few changes in species frequency. Changes in permanent plots were greater during the first than during the second half of the study period. In exclosures that were installed halfway through the study period, there was a relatively rapid recovery of previously dominant species that had decreased during the first half of the study period.

Species richness per unit area in the reserve increased. At the seaward side of the marsh, the altered management allowed succession to proceed leading to establishment of stands of Phragmites australis, whereas on the landward side, the combination of moderate grazing with neglect of the drainage system appeared an effective measure in maintaining habitats for a wider range of halophytic species.

Nomenclature: Anon. (1998).

The effects of reduction and cessation of sheep grazing on salt‐marsh vegetation were studied on a formerly intensively grazed salt marsh in northern Germany. Plant species cover was recorded in 45 permanent plots from 1992 to 2000. In 1995, physical and chemical soil parameters were analysed. Results of Redundancy Analysis (RDA) indicated that salinity and the depth of anoxic conditions below the surface were the most important soil factors related to the spatial vegetation pattern. Furthermore, plant species distribution was influenced by present and past grazing intensity, by soil grain size and nitrogen content.

Vegetation changes over 9 yr were analysed by non‐linear regression. The cover of Aster tripolium, Atriplex portulacoides, and, to a lesser extent, Artemisia maritima and Elymus athericus increased due to reduced grazing pressure, whereas the cover of Salicornia europaea decreased. After a strong increase in the first years Aster decreased 2 to 6 yr after abandonment. In the mid salt‐marsh zone Puccinellia maritima was replaced by Festuca rubra. The cover of Puccinellia, Festuca, Suaeda maritima, Glaux maritima and Salicornia fluctuated strongly, probably due to differences in weather conditions and inundation frequency. Species richness per 4 m² generally increased while vegetation evenness decreased during the study period. Only in the high salt marsh abandoned for 9 yr did the number of species decrease slightly. Thus far, cessation of grazing did not lead to large‐scale dominance of single plant species.

Nomenclature: Wisskirchen & Haeupler (1998).

Abbreviation: RDA = Redundancy Analysis.

Vegetation succession in three back‐barrier salt marshes in the Wadden Sea was studied using a data set comprising 25 years of vegetation development recorded at permanent quadrats. The effect of livestock grazing on succession was assessed by comparing quadrats where grazing was experimentally prevented or imposed. We studied changes at the species level as well as at the level of the plant community. Special attention is given to effects on plant species richness and community characteristics that are relevant for lagomorphs (hares and rabbits) and geese. Inundation frequency and grazing were most important in explaining the variation in species abundance data. The three marshes studied overlap in the occurrence of different plant communities and the observed patterns were consistent between them. Clear differences in frequency and abundance of plant species were observed related to grazing. Most plant species had a greater incidence in grazed treatments. Species richness increased with elevation, and was 1.5 to 2 × higher in the grazed salt marsh. Grazing negatively influenced Atriplex portulacoides and Elymus athericus, whereas Puccinellia maritima and Festuca rubra showed a positive response. The communities dominated by Elymus athericus, Artemisia maritima and Atriplex portulacoides were restricted to the ungrazed marsh. Communities dominated by Puccinellia maritima, Juncus gerardi and Festuca rubra predominantly occurred at grazed sites. As small vertebrate herbivores prefer these plants and communities for foraging, livestock grazing thus facilitates for them.

Nomenclature: van der Meijden (1990) and Schaminée et al. (1998).

This study focuses on the relationship between vegetation succession and soil seed bank composition on the Schiermonnikoog (The Netherlands) salt marsh over 100 yr. The importance of driftline material in seed dispersal and the relationship with succession is also investigated. The results indicate that the majority of species have a transient or short-term seed persistent bank. Seeds of most species are able to float over the salt marsh and become concentrated in the driftline higher up the marsh. After plants have established a seed bank forms, which disappears when vegetation is replaced by later‐successional species. Exceptions are Spergularia maritima which is still present in the seed bank of late successional stages, and Juncus gerardi and Glaux maritima which appear in the seed bank of early successional stages, but are absent in the vegetation. Based on the results of this study constraints and possibilities for salt‐marsh restoration by de‐embankment are discussed.

Nomenclature: van der Meijden (1990).

Wooded meadows on the Baltic Island of Öland result from traditional agricultural management over centuries which has led to a species‐rich vegetation with high species diversity. Today, nearly all of these meadows have been abandoned and became rapidly overgrown by deciduous shrub and tree species forming a closed canopy which resulted in a rapid and strong decrease in species numbers of the herb layer. Recent efforts aim to restore overgrown wooded meadows by cutting single shrubs and trees to open the canopy. However, the effects of abandonment as well as of any restoration management in wooded meadows have rarely been documented until now. Mechanisms driving succession after restoration such as the dispersal potential of the respective species over time and space have not been analysed yet. Therefore, a chronosequence was studied which included a traditionally managed wooded meadow, an overgrown meadow which has been abandoned for more than 100 yr and a meadow which was restored 36 yr ago by cutting and is now grazed. We analysed the soil seed bank of the 3 meadows in comparison with the established vegetation and endozoochorous seed dispersal by cattle and sheep. After abandonment 87% of the typical grassland species vanished from the established vegetation and were replaced by species characteristic of woodland and disturbed grassland communities. The mean number of species decreased from 52 species per plot (4 m²) to 18 species. Mean species number and number of seeds in the seed bank declined significantly from the traditionally managed to the overgrown meadow. Most of the grassland species were assigned to a transient seed bank type while only 1/3 could be classified as having a short‐term persistent seed bank. Thus, restoration of wooded meadows cannot rely on the soil seed bank. Endozoochorous seed dispersal by cattle and sheep was shown for 15% of the species with seed densities per 100 g air dried dung of 737 and 767, respectively. Movement of animals between ancient and restored wooded meadows is recommended since many of the species only occurred in low densities and therefore, will probably not be found in the dung samples.

Nomenclature: Oberdorfer (1994).

The patterns of species establishment, persistence and spread in a long‐term experiment investigating the re‐creation of chalk grassland using different seed mixtures on ex‐arable land were analysed with the intention of providing enhanced re‐creation/restoration prescriptions and a critique of experimental designs. Species had a wide range of behaviours; (1) species that did not establish from seed e.g. Blackstonia perfoliata, (2) establishment but poor persistence in closed sward e.g. Hieracium pilosella, (3) establishment and persistence but little spread e.g. Onobrychis viciifolia and (4) good establishment and spread over all treatments e.g. Centaurea nigra and Trisetum flavescens. Persistence appeared greater in species with lower germination rates in both light and dark. Spread was greater in species with higher seed mass and lower dark germination rates.

However, results from small‐plot experiments should be critically analysed. Though initial results show the potential for re‐establishment of vegetation, subsequent vegetation dynamics may be more closely related to the invasion of species from other treatments than the original species sown. Experimental designs should employ either large plots and/or wide guard rows to extend their useful life span. Long‐term data show which species are useful for cost‐effective restoration. Some species need to be sown over the whole area to provide cover (a ‘grass matrix’) and competition with arable weeds. Others need to be sown over wide areas as they spread poorly. Some species can be sown at low densities or in small patches as they have the ability to spread in closed vegetation.

Nomenclature: Clapham et al. (1987).

Due to economic pressures and policy changes Lolium perenne‐ Trifolium repens sown swards in upland UK sheep systems are likely to become less intensively managed. We present results from the first 5 yr of a long‐term experiment studying vegetation change under more extensive grazing management at three sites. One treatment was representative of current, intensive management and 5 were unfertilized with different intensities of seasonal grazing. The species composition of unfertilized, ungrazed swards changed dramatically within 2 yr and the sown species had virtually disappeared by year 5. Ranunculus repens, Poa trivialis, Agrostis gigantea, Juncus spp. and Carex spp. became dominant at the wettest site. Grasses were dominant at the other sites. In contrast, the sown species were retained in the unfertilized, grazed treatments; there were small shifts in abundance of the species present initially and few additions or losses of species. Some colonizing species were present in the seed bank whereas others with a transient seed bank appeared to have invaded from neighbouring vegetation. Implications of these results for compensation schemes to reduce animal output and increase biodiversity are discussed.

Nomenclature: Stace (1991)

To identify management treatments suitable for the conservation of extensively managed grasslands, the ‘Fallow experiments in Baden‐Württemberg’ were set up in 1975. In this investigation, species composition of the grazing, mowing, mulching, controlled burning and unmanaged (succession) treatments were analysed after 25 yr of continuous management in Arrhenatherum elatius and Bromus erectus grasslands. Through ordination analyses it was found that species composition is strongly dependent on the management treatment. The first axis, identified by ordination analysis, essentially corresponded to a gradient of decreasing disturbance frequency. Controlled burning resulted in a unique species composition. Grazing, mowing and mulching twice a year were found to be most suitable for the conservation of unimproved, species‐rich grasslands.

Nomenclature: Oberdorfer (1994).

The upper courses of brook valley systems harbour Nardo‐Galion saxatilis communities characteristic of oligotrophic soils under low‐intensity farming. Most of these communities have disappeared under intensified farming i.e. application of fertilizers. We studied the possibilities of restoration i.e. re‐establishment of the former plant community by adopting various cutting regimes after the cessation of fertilization in 1972. The various cutting regimes revealed different effects after 25 yr. Regimes with cutting every second year with or without removal of the swath, and complete abandonment deviated from the other regimes that included annual haymaking with different frequency and timing. The latter group of cutting regimes came closer to the community of an adjacent field where fertilization stopped in 1967. This field in turn harboured several Nardo‐Galion species after 25 yr of annual cutting, and showed more resemblance with a local reference community (at a distance of 500 m) that had not been fertilized since the 1940s. The local reference still does not match poorly developed Nardo‐Galion saxatilis communities found in the region of ca. 50 km around the study area, and is far from well developed Nardo‐Galion communities in the same region.

The study site still harbours several species characteristic of eutrophic soil and few species characteristic of oligotrophic soil after 25 yr of annual cutting and removal of the swath. The soil seed bank harbours only few target species. Although species characteristic of oligotrophic soil are present in an adjacent field and Nardo‐Galion saxatilis species occur at 500 m, they have not (yet) established in the target area.

Nomenclature: van der Meijden(1990).

Within the framework of the Dutch ‘Network Ecological Monitoring’, a large set of new permanent plots has been established to monitor selected plant communities throughout The Netherlands for studying the effects of environmental changes on species composition of semi‐natural communities. This national programme will also make use of pre‐existing permanent plots. These plots reflect the long and comprehensive history of research using permanent plots in The Netherlands, where the first permanent plots were established in the early 1930s. To enhance the usefulness of pre‐existing permanent plots, a comprehensive permanent plot database was compiled. This database was derived from the Dutch National Vegetation Database, that was established for the recent vegetation classification of The Netherlands. This was supplemented with information from various organizations and a number of individual researchers. Currently, the permanent plot database contains ca. 6000 permanent plots. More than 2500 of these plots have been sampled at least 5 ×, and ca. 1500 plots at least 10 ×. Most of the plots are from grasslands, followed by forests and dune systems.

This database not only provides insight into vegetation succession, fluctuations within plant communities over time, and the effects of changes of the environment on the vegetation but, indirectly, it also offers the possibility of studying the long‐term behaviour of individual plant species (e.g. establishment, competition, longevity). For the Network Ecological Monitoring a selection of these (historical) plots will be added to the new network of permanent plots in The Netherlands, thus supplying information of past vegetation conditions.

The response of Larrea divaricata and L. cuneifolia to cutting stems 0–20 cm above the ground was studied in the arid piedmont area west of Mendoza, Argentina. The species occur at different elevations (750–1250m), whileand in vegetation zones: L. cuneifolia < 1250 m ; L. divaricata between 1250 and 2500 m. Four treatments with 10 replicates were analysed in randomly chosen plants: cut at ground level with lopping shears; cut at ground level with a pick; cut at 10 cm with lopping shears; and cut at 20 cm with lopping shears. The initial and final height, volume, and dry matter (above‐ and below‐ground) were determined. The relation between volume and initial and final dry matter and height was analysed through a factorial MANOVA (p< 0,05), and the functional relation between volume, dry matter and height was estimated by adjusting a regression model. In both species, maximum recovery was reached when cut with shears, and predicted recovery (turnover) was 17–18 yr. In the two last treatments height was a useful predictor of dry matter. L. divaricata ‐dominated plots have a lower biomass, growth rate, and allocation to stems and root than L. cuneifolia ‐dominated plots. Regrowth following clipping on an area of 3–10 ha, is sufficient to support the annual needs (cooking and heating) of one family.

Data from more than 900 vegetation plots surveyed in the evergreen shrublands of southern California were used to develop predictions of the distributions of eight dominant shrub species for a 3880 km² region. The predictions, based on classification tree (CT) models, were validated using independent field data collected during a vegetation survey conducted in the 1930s. Presence and absence were correctly predicted an average of 75% of the time for the eight species. At the same time, these models minimized false positives, so that presence was predicted in the correct proportion of the cases for most species. The areal proportion of the landscape on which the species were predicted to occur was in the same rank order, and of the same magnitude, as their frequency (proportion of plots in which they occurred) within the field data sets. Predictive maps of species presence were overlaid and combined with an existing regional vegetation map. The shrub species ‘assemblages’ that resulted from this procedure had analogs with vegetation series defined using field data in previous studies. The resulting multiple species map will be used in a landscape simulation model of fire disturbance and succession.

Abbreviations: CT = Classification tree; CCR = Correct classification rate; PPP = Positive predictive power; TMI = Topographic moisture index; USDA = United States Department of Agriculture; VTM = Vegetation type map.

Nomenclature: Hickman (1993).

This study assesses the utility of modelling approaches to predict vegetation distribution in agricultural landscapes of southwestern Australia. Climate surfaces, hydrologic and erosion process models are used to link vegetation to environmental variables. Generalized additive models (GAM) are derived for presence/absence data of mapped vegetation types. Vegetation distribution shows significant responses to rainfall and subsequent water redistribution due to the relief; however, these variables are insufficient to effectively explain vegetation patterns at the local scale. Accordingly, prediction accuracy remains low (k‐values below 0.5). The striking unpredictability of the local distribution of the vegetation in the Wheatbelt is discussed with regard to the performance of topographically driven processes in subdued landscapes and with regard to geological, historical and biological factors determining the southwestern Australian plant species distribution.

Nomenclature: Chapman et al. (in prep.).

Abbreviations: AVHGT = average altitudinal height of the upslope area; AVSLP = average slope of the upslope area; CURVPL = plan curvature; CUPL500 = plan curvature in a 1.5 km window; CURVPR = profile curvature; DEM = Digital Elevation Model; DIRIDGE = distance from ridges; DROUGHT = drought index; EROS = sediment transport index; GAM = Generalized Additive Model; HABOVE = height above streamlines; RAIN = annual rainfall; SLOPE = maximum slope of the surface; STRP = stream power index; WET = wetness index.