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Two investigations into the translocation of temperate deciduous woodland soil were carried out in Kent, S. E. England, to study the effects on C and N mineralisation. In the field experiment, two translocation methods were compared: (i) placement, moving soil as an intact surface profile and (ii) loose-tipping in which the surface profile was mixed. These were implemented in winter bothin situ(under the woodland canopy) andex situ(soil moved to a receptor site outside woodland). In a second experiment, intact soil cores from the woodland site were subjected to different levels of disturbance in a polythene tunnel environment. Measurements of soil CO2 evolution and N mineralisation in both experiments showed a clear seasonal pattern, strongly influenced by temperature. Over a 7-month period, cumulative net N mineralisation in the field was greater in the woodland controls and placement treatments than loose-tipping treatments. Soil CO2 emissions were also greater in woodland control plots in the winter compared withex situtreatments. Similarly, in the polythene tunnel environment, CO2 emissions were highest in the undisturbed soil cores, while N mineralisation varied with soil depth but, across the whole profile, was also greater in the controls. We conclude that the mixing of organic rich topsoil with mineral subsoil in clayey soil may have protected the organic residues on the clay-silt surfaces, resulting in overall lower mineralisation rates in the disturbed soil. These results indicate that N mineralisation does not necessarily increase when soil translocation operations are carried out on clayey soils in winter. Placement methods appeared the most likely to conserve soil mineralisation processes close to those in undisturbed woodland soil, but depend greatly on the success of maintaining the soil profile intact. It appears that, on clayey soils, the development of vegetation at the receptor site is more likely to be determined by alterations in the light, soil temperature and moisture regime that will occur in open conditions after woodland translocation than from increased soil N supply. [ABSTRACT FROM AUTHOR]

The forest under-storey herbsAnemone nemorosa,Lamiastrum galeobdolonandVeronica montanaare 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,Urticadioica, 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 ofA. nemorosa,L. galeobdolon,V. montana, Poa trivialisandU. dioicawas 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. trivialisandU. 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. [ABSTRACT FROM AUTHOR]