Precipitation is the main water source for vegetation survival in arid and semi-arid areas. However, previous studies always focus on the effects of precipitation in different time scales, but ignore the effects of precipitation in different spatial scales. To further study the effects of precipitation fluctuation in different spatial scales, we used the wavelet analysis method to analyze its t...

in this paper, the temperature and annual precipitation data has been applied in 44 years for the synoptical stations northwest zone of iran. among the stations, eight of them, which have the perfect data and coverage, has been considered to analysis applied. in this study transfer function models have been used to analysis time series. in this method, firstly, the stations have been modeled th...

The complex topography and high climatic variability of the North Western Mediterranean Basin (NWMB) require a detailed assessment of climate change projections at high resolution. ECHAM5/MPIOM global climate projections for mid-21st century and three different emission scenarios are downscaled at 10 km resolution over the NWMB, using the WRF-ARW regional model. High resolution improves the spa...

Net primary production (NPP), the difference between CO2 fixed by photosynthesis and CO2 lost to autotrophic respiration, is one of the most important components of the carbon cycle. Our goal was to develop a simple regression model to estimate global NPP using climate and land cover data. Approximately 5600 global data points with observed mean annual NPP, land cover class, precipitation, and ...

We studied discharges of organic carbon from eight contiguous small watersheds on the Atlantic Coastal Plain in Maryland for up to 24 yr. Six of these watersheds were second or third order with mixed-land-use, while two were first order (one completely forested and one highly dominated by cropland). These watersheds have perched aquifers, so all groundwater discharges as well as surface runoff ...

The distribution of evaporation minus precipitation over the globe and its seasonal variations are estimated from global atmospheric circulation statistics for the period May 1963 to April 1973. Meridional profiles of evaporation minus precipitation over the Atlantic, Pacific, and Indian oceans, over all oceans combined, and over all continents combined, as well as the total evaporation minus p...

Savanna ecosystems are dominated by two distinct plant life forms, grasses and trees, but the interactions between them are poorly understood. Here, we quantified the effects of isolated savanna trees on grass biomass as a function of distance from the base of the tree and tree height, across a precipitation gradient in the Kruger National Park, South Africa. Our results suggest that mean annua...

Deconstructing the drivers of large-scale vegetation change is critical to predicting and managing projected climate and land use changes that will affect regional vegetation cover in degraded or threated ecosystems. We investigate the shared dynamics of spatially variable vegetation across three large watersheds in the southern Africa savanna. Dynamic Factor Analysis (DFA), a multivariate time...

The development of isotopic baselines for comparison with paleodietary data is crucial, but often overlooked. We review the factors affecting the carbon (δ(13)C) and nitrogen (δ(15)N) isotopic compositions of plants, with a special focus on the carbon and nitrogen isotopic compositions of twelve different species of cultivated plants (n = 91) and 139 wild plant species collected in northern Per...