To predict forest response to long-term climate change with high confidence requires that dynamic global vegetation models (DGVMs) be successfully tested against ecosystem response to short-term variations in environmental drivers, including regular seasonal patterns. Here, we used an integrated dataset from four forests in the Brasil flux network, spanning a range of dry-season intensities and...

The factors that trigger sudden, seasonal movements of elephants are uncertain. We hypothesized that savannah elephant movements at the end of the dry season may be a response to their detection of distant thunderstorms. Nine elephants carrying Global Positioning System (GPS) receivers were tracked over seven years in the extremely dry and rugged region of northwestern Namibia. The transition d...

The interannual variation of the Bowen ratio, through its effect on the warming extent of available energy to the ecosystem land surface air, heavily influences the ecosystem microclimate and affects the hydrological cycle at both regional and global scales. Although the precipitation amount in southeast China is not expected to change greatly as a result of climate change, the precipitation fr...

In the dry forest of Santa Rosa National Park, Costa Rica, the understory shrub Jacquinia nervosa presents an inverse pattern of phenology that concentrates vegetative growth and reproduction during the dry season. In this study, we tested the "escape from herbivory" hypothesis as a potential explanation for the inverse phenological pattern of J. nervosa. We monitored leaf, flower and fruit pro...

Oxygen and carbon isotopic compositions of ambient carbon dioxide in two tropical forests in the Amazonian basin were determined at the beginning and the end of the dry season. One site, Fazenda Vitoria, is typical of a seasonal forest with a pronounced dry season from May to November whereas the other site, Reserva Ducke, has a milder dry season. Samples collected at night revealed that in the...

We present results of two intensive mark-release-recapture surveys conducted during the wet and dry seasons of 2008 in the villages of Fourda and Kenieroba, Mali. The former is a small fishing village by the Niger River with a moderate to high densities of Anopheles gambiae Giles s.s. (Diptera: Culicidae) throughout the year, while the latter is a large agricultural community 2 km inland that e...

Imidacloprid is a systemic insecticide used widely in controlling mites, mealy bugs and other related pests in fruits, vegetables and tea. The dissipation behaviour of imidacloprid residues in green tea shoots, made tea and its transfer potential from made tea to infusion in hot water was studied. Analysis in tea matrices of imidacloprid was carried out using high-performance liquid chromatogra...

The physiological response of plants growing in their natural habitat is strongly determined by seasonal variations in environmental conditions and the interaction of abiotic and biotic stresses. Here, leaf water and nutrient contents, changes in cellular redox state and endogenous levels of stress-related phytohormones (abscisic acid (ABA), salicylic acid and jasmonates) were examined during t...

Above- and belowground phenology and water relations of Enterolobium cyclocarpum Jacq. trees in the dry forest of Santa Rosa National Park, Costa Rica were studied during two consecutive phenological cycles, from November 1998 to June 2000. Aboveground phenological activity, including leaf shedding, growth and maturation of dormant fruits, new leaf flushing and flowering, occurred during the dr...

A study was conducted to evaluate serum and tissue micro-mineral concentrations of sheep and goats at the end of the dry and wet seasons in Trinidad. Tissue Samples for analysis were taken from the same liver lobe, the kidney cortex mainly (and outer medulla) and the cerebral hemispheres. Tissue sample trace concentrations were for Cu, Zn, Fe and Mn were determined by Atomic absorption spectros...