Saplings of one half-sib family of birch, Betula pendula Roth, were exposed to three ozone concentrations (non-filtered air (NF); non-filtered air + 10-20 nmol O(3) mol(-1) (NF+); non-filtered air + 40-60 nmol O(3) mol(-1) (NF++)) in open-top chambers during two growing seasons from 1997 to 1998. Shed leaves were collected regularly during both growing seasons and, in 1998, the dry mass (DM) an...

to nadir-viewed vegetation reflectance data. Variability INTRODUCTION in tissue optical properties was wavelength-dependent. During the past several decades, the tools for vegetation For green foliage, the lowest variation was in the visible remote sensing have evolved significantly. Optical remote (VIS) spectral region and the highest in the near-infrared sensing has expanded from the use of p...

We evaluated fungal biomass (as ergosterol concentration) and invertebrate colonization during leaf breakdown of Picramnia sellowii Planch. (Picramniaceae) in pools and riffles of three low-order forested streams in southeastern Brazil. We hypothesized that leaf breakdown will be higher in riffles due to the high physical fragmentation and fungal activity. The experiment was carried out during ...

Samples of leaf litter were collected from 22 woodland sites throughout Prince Edward Island, Canada. Eighty-two specimens belonging to 15 species litter-dwelling land snails recovered 20 the samples. One-third species— Carychium exile H.C. Lea, 1842, Helicodiscus shimeki Hubricht, 1982, Strobilops labyrinthicus (Say, 1817), Perpolita binneyana (Morse, 1864), and Striatura ferrea Morse, 1864—we...

This study investigated changes in diversity of shrub-tree layer, leaf decomposition rates, nutrient release and soil NO fluxes of a Brazilian savanna (cerrado sensu stricto) under N, P and N plus P additions. Simultaneous addition of N and P affected density, dominance, richness and diversity patterns more significantly than addition of N or P separately. Leaf litter decomposition rates increa...

We lack both a theoretical framework and solid empirical data to understand domestication impacts on plant chemistry. We hypothesised that domestication increased leaf N and P to support high plant production rates, but biogeographic and climate patterns further influenced the magnitude and direction of changes in specific aspects of chemistry and stoichiometry. To test these hypotheses, we use...

it has often been stated or implied that grazing is an important factor in the land degradation process, a suggestion supported by various research projects, and this study investigated the effect of livestock grazing on stem height, crowncover, production, basal diameter, stem biomass, litter, leaf-stem index (leaf to stem weight) , root diameter and weight and seed production per individual o...

we studied litterfall dynamic of tree plantations in dez river floodplain, at 14 to 15 years old. the plantations consist of populus euphratica oliv., eucalyptus camaldulensis dehnh., e. microtheca f. muell, acacia farnesiana (l.) willd., a. salicina lindl., a. saligna (labill.) h. wendl., a. stenophylla benth. and dalbergia sissoo roxb. litterfall was different between the tree species, and le...

We measured breakdown rates of leaves and small wood for the first three years in a stream in which detrital inputs were excluded for 7 years and in a reference stream located in the Appalachian Mountains of North Carolina, USA. Leaf and wood inputs were excluded using a gill-net canopy constructed over a 170-m section of stream. We hypothesized that red maple (Acer rubrum) and rhododendron (Rh...