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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]

We compared the species composition, occurrence and diversity of understorey of forestry plantations and semi-natural secondary forests in a warm-temperate region in southeastern Kyushu, Japan, in which the previous land-use history had been documented. Cluster analysis and a stand ordination, using detrended correspondence analysis, indicated that plant species composition in forest stands was primarily influenced by the previous land-use history (as meadows or coppices) compared with either the current status of the stand (semi-natural forest or plantation) or site micro-topography. Species occurrence was also dependent on the previous land-use, with a significantly greater proportion of native woodland species being present in former coppice stands. Species richness, however, was higher in plantations and stands developing on former meadow sites. This was true of perennial forbs and climbing plants, but not the evergreen species which were originally common in native woodland of the region. Species diversity indices (Shannon’s H′) showed a similar tendency to species richness. The light environment within forest stands, evaluated by gap light intensity (GLI) using hemispherical photography, had less effect on species richness. We conclude that previous land-use has a significant effect on the species composition and diversity of forest, persisting even after the establishment of conifer plantations, and that the restoration of the original ‘woodland’ species composition and diversity will require the retention of efficient seed sources near stands which have developed on land previously cleared of native forest cover. [Copyright &y& Elsevier]