The data used in the present study is a 21-year GIMMS-NDVI dataset, surface data on phenology of birch, and temperature data from meteorological stations, all for the period 1982 to 2002. For each pixel a 21-year mean and a mean of peak NDVI value was computed. Threshold values related to this mean, and mean of peak NDVI values, which show the best correlations with the phenological field data ...

While recent studies have elucidated many of the factors driving parasite dynamics during the growing season, the ecological and evolutionary dynamics during the off-season (i.e. the period between growing seasons) remain largely unexplored. We combined large-scale surveys and detailed experiments to investigate the overwintering success of the specialist plant pathogen Podosphaera plantaginis ...

Antioxidant activities in the leaves and fruits of wild Vaccinium arctostaphylos (locally named Qare-Qat) from diff erent regions of Iran were evaluated using the stable 1, 1-diphenyl-2-picrylhydrazyl free radical and ferric reducing/antioxidant power methods. Variations in antioxidant activity, total phenolic, anthocyanin, and fl avonoid content in fruit samples among genotypes was much greate...

Climatic warming is expected to particularly alter greenhouse gas (GHG) emissions from soils in cold ecosystems such as tundra. We used 1 m(2) open-top chambers (OTCs) during three growing seasons to examine how warming (+0.8-1.2 °C) affects the fluxes of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) from alpine tundra soils. Results showed that OTC warming increased soil CO2 effl...

Objective: An increasing number of studies have reported on shifts in timing and length of the growing season, based on phonological, satellite and climatologically studies. Changes in the timing and length of the growing season (GSL) may not only have far reaching consequences for plant and animal ecosystems, but persistent increases in GSL may lead to long-term increases in carbon storage and...

Understanding the effects of climate on vital rates (e.g., survival, development, reproduction) and dynamics natural populations is a long-standing quest in ecology, with ever-increasing relevance face change. However, linking drivers to demographic processes requires identifying appropriate time windows during which influences rates. Researchers often do not have access long-term data required...

Sweetgum, Liquidambar styraciflua L. (Hamamelidales: Hamamelidaceae), is a species of interest for short-rotation plantation forestry in the southeastern United States. Despite its high levels of resistance to many native insects and pathogens, the species is susceptible to generalist defoliators during outbreak epidemics. The objective of this field study was to evaluate the potential impact o...