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The species richness of trees, shrubs and climbing plants was investigated in 41 sugi (Cryptomeria japonica D. Don) plantations of different stand age and area in southern Kyushu, southwestern Japan. Altogether 174 species were found, of which 145 infrequent species were selected for analysis. Two groups were extracted from the species list according to their occurrence in older (49 spp.) or younger (28 spp.) stands, the latter containing a higher percentage of climbing plants and species with wind-dispersed seeds. In contrast, the older stand group contained major tree components typical of seminatural, evergreen broadleaved forests in the region and was more heavily dependent on stand age, especially for species with gravity-and frugivoredispersed seeds, showing a gradual increase up to 60 years old. The species richness was less correlated with edge perimeter facing seminatural forests and the years after latest thinning. The juxtaposition of plantation compartments with stands of seminatural forest or other plantations, as well as the compartment's origin as former plantation site or a seminatural stand, had relatively little influence on species richness. However, topographic variation was important in determining the species composition, with valley stands having higher species richness and containing many plants typical of the regional seminatural forests. These results suggest that (1) the major trend of species richness is determined by the presence of old stand type species, (2) topographic variation of species richness remains even after establishment of plantations, and (3) the normal rotation period of sugi plantations (35-40 years) may therefore be too short to conserve the maximum potential species diversity within the working forest.

Summary1. Although application of fertilizers and pesticides to farmland is known to impact non-target organisms in adjacent semi-natural habitats, little is known of the impact on woodland understorey communities, which have considerable conservation significance in the arable landscapes of the UK and elsewhere in Europe. This study investigated the impacts of agrichemicals on several plant species typically found in ancient seminatural communities. 2. Six species of woodland plants were exposed to the herbicide glyphosate at concentrations equivalent to those measured in spray drift trials (1-25% of the full application rate) in short-term greenhouse and long-term field experiments. Fertilizer was applied to half of the plants at a concentration likely to be seen in overspread situations (70 kg ha − 1 year − 1 ). The distribution of the same species was surveyed in woodland margins adjacent to fields with high, medium and low agrichemical inputs. 3. In both greenhouse and field experiments, herbicide treatments at drift concentrations caused increased mortality, reduced biomass and reduced fecundity in all species, although to differing degrees. The threshold of sensitivity to glyphosate was as low as 1% of the median field application rate for the most sensitive species. Fertilizer treatment affected resource partitioning in Carex remota and Galium odoratum and reduced the fecundity of G. odouratum . 4. In field surveys, the abundance of the most sensitive species was highest in woodland margins adjacent to fields with low agrichemical inputs and lowest beside high-input farmland. These differences were seen at least 4 m into woodland margins but were not found at 10 m. 5. Synthesis and applications . There was considerable agreement between the shortterm greenhouse and long-term field experiments, although long-term impacts may have been underestimated in the former. Adverse impacts of pesticide drift have been demonstrated to affect a variety of plants of woodland margins bordering farmland. Differences in the distribution of species most sensitive to herbicide extend to at least 4 m into woodland margins. We recommend the adoption of no-spray buffer zones of at least 5 m to protect the majority of woodland species from the impacts of agrichemicals applied to adjacent land.

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The forest under-storey herbs Anemone nemorosa, Lamiastrum galeobdolon and Veronica montana are generally considered indicator species of old, broadleaved woodland sites where the soil fertility is often low. In a glasshouse bioassay, however, all three species not only showed large positive growth responses to supplied P concentrations (0-10 mg L )1 ) solutions, but also tolerated high P concentrations (20-40 mg L )1 ), well above those normally found in their natural habitat. Plants responded by raising the concentrations of P in their shoot and root tissues and increasing their biomass, resulting in an increased P uptake. A shade-tolerant competitor species, Urtica dioica, also grew vigorously across the full range of P concentrations, restricting the growth of the woodland species. This emphasises the difficulty of establishing semi-natural woodland vegetation in the presence of competitor species, for example in situations where new woodlands are planted on fertile ex-agricultural soils containing large residual concentrations of P. The influence of soil pH on the growth and nutrient relations of A. nemorosa, L. galeobdolon, V. montana, Poa trivialis and U. dioica was determined in a separate experiment using an ex-arable soil as the growing medium with pH levels adjusted from 7.4 to 5.8 and 4.3 respectively. Acidifying the soil enhanced growth, but reduced the concentrations of N, P and K in the leaves of all three woodland species, probably due to dilution of these minerals in the increased dry matter production. The competitor species (P. trivialis and U. dioica) responded in similar manner to the woodland indicator species. These results suggest that manipulating soil pH as a means of facilitating the establishment of woodland indicator species in new farm woods is unlikely, in the short term, to be effective where competitor species are present.

Coppice systems are amongst the earliest forms of woodland management known and on some sites their use has been documented for centuries. Distinctive assemblages of plants and animals are associated with such systems and are highly valued in nature conservation terms. The richness of such assemblages, and conversely, the species that do not thrive under coppice, are linked to the alternation of relatively short light and dark phases and the juxtaposition of stands at different stages in the coppice cycle. We review how and why the biodiversity of former coppice woods changes in response to abandonment and conversion to high forest. We focus on the situation in the UK, based on recent published literature searches and the authors' extensive experiences of the practical issues involved in the conservation of coppice woodland systems. Vascular plants in the ground flora, invertebrates of open glades and scrub, and small birds of the understorey may have become more abundant in coppice than they would have been under 'natural' forest conditions. By contrast epiphytes dependent on mature trees and species of largesized deadwood are less favoured by coppice management. Coppice systems developed to meet the local community needs. As social and economic conditions changed, so coppicing declined and the woods were transformed into high forest through neglect or deliberate management. High forests differ from coppice stands in their spatial and temporal dynamics and consequently in their wildlife particularly with respect to their vertical structure pattern; extent of open space and young growth; spatial heterogeneity; tree and shrub composition; and browsing levels. Three issues for the conservation of biodiversity arise from these changes: 2  what priority and resources should be given to halting further decline, by maintaining coppice compared to allowing sites to develop with more 'natural' high forest structures and dynamics; will associated high-forest species recolonise?  if we restore coppice systems, will the species assemblages present in the past also recover, under current and future changes in environmental conditions; i.e is the transformation reversible under current environmental conditions?  are there other ways in which 'coppice-associated' species might be maintained? We identify research gaps and proposals to address these issues.

Abstract. The Channel Tunnel workings on the UK side have yielded nearly 4 million m3 of chalk‐marl spoil which now forms a 36 ha landscaped reclamation platform. To establish vegetation of amenity and conservation interest on the spoil, seed mixtures of native wild flowers and grasses were sown with Lolium perenne (perennial rye grass) as a nurse species. Potentially, L. perenne is a suitable nurse species for grassland creation on infertile substrates as it provides rapid initial cover and stability, but it is non‐persistent and declines in vigour with time, allowing wild flower species sown alongside to expand their cover and spread in the longer term. On very low fertility substrates like chalk marl, an initial application of fertilizer is needed to encourage plant growth. Results are reported of a fertilizer experiment on Channel Tunnel spoil to determine appropriate levels of fertilizer for establishment of species‐rich grassland vegetation. An area hydroseeded with L. perenne and wild flowers in autumn 1992 was subjected to factorial treatment of four levels each of N and P in spring 1993. The results the following summer showed significant positive effects of nitrogen and phosphorus on L. perenne biomass and a negative impact of nitrogen on densities of wild flower species, especially legumes, establishing in the L. perenne sward. In general, low fertilizer applications encouraged low productivity and maximal species richness in the vegetation. Conversely high applications encouraged high productivity and competitive exclusion of sown wild flower species. Fertilizer applications must therefore balance encouragement of the stabilising nurse grass sward, while preventing competitive exclusion of wild flowers by the nurse grass.

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