As global temperatures rise, variation in annual climate is also changing, with unknown consequences for forest biomes. Growing forests have the ability to capture atmospheric CO2 and thereby slow rising CO2 concentrations. Forests' ongoing ability to sequester C depends on how tree communities respond to changes in climate variation. Much of what we know about tree and forest response to clima...

Our current knowledge on climate-mediated effects on human population dynamics is based on preindustrial agrarian societies where climate-induced crop failures had a major impact on fertility and mortality rates. However, because most of the human evolutionary history has been shaped by hunter-gatherer lifestyle relying on diverse plant and animal food sources, it is also important to understan...

Antarctic krill is thought to undergo an annual cycle of biological processes to cope with seasonal changes in their environment. The question of whether, and to what degree, seasonal environmental parameters such as photoperiod, food availability and temperature govern metabolism in krill is not clear. In this long-term laboratory study, respiration rates were determined in krill incubated und...

introduction the city population, in particular at the industrialized cities and centers of provinces, has increased dramatically in iran during recent decades. arak city is among of those industrialized cities as a centers of markazi province which has experienced a fast increase in population. this changes in population numbers tend to increase in consuming water resources as well as increasi...

Hyper-arid regions are expected to undergo climatic change, but only a few research works have so far been conducted on the dynamics of carbon dioxide (CO2) fluxes and their consequent responses to various bioclimatic factors, which is mainly attributable to a limited set of flux observations. In this study, the CO2 fluxes exchanged between the forest and the atmosphere have been measured conti...

BACKGROUND The aim of this study was to determine trends in the airborne pollen concentration and pollination period for the principal sources of pollen in Badajoz (southwest Spain) over 15 years of monitoring (1994-2008). METHODS Airborne pollen was monitored by continuous sampling with a Hirst volumetric sampler. Pollen trends were investigated by linear regression and correlation analysis ...

Forest autotrophic respiration (R(a)) plays an important role in the carbon balance of forest ecosystems. However, its drivers at the global scale are not well known. Based on a global forest database, we explore the relationships of annual R(a) with mean annual temperature (MAT) and biotic factors including net primary productivity (NPP), total biomass, stand age, mean tree height, and maximum...

This study revealed a new regime shift in the North Pacific annual mean sea surface temperature (SST) 2013/14, robust multiple SST data sets. shows horseshoe pattern with warming along American western coast and toward Central Pacific. It suggests phase reversal of Victoria Mode (VM) it seems unrelated to Decadal Oscillation (PDO) Interdecadal (IPO). Associated this shift, air significantly enh...

BACKGROUND An up-to-date and reliable map of podoconiosis is needed to design geographically targeted and cost-effective intervention in Ethiopia. Identifying the ecological correlates of the distribution of podoconiosis is the first step for distribution and risk maps. The objective of this study was to investigate the spatial distribution and ecological correlates of podoconiosis using histor...