based on the importance and role of species diversity and richness as ameasurement of the health of an ecosystem; studying of their components can lead toevaluate the health condition of rangeland. this research was carried out in a part ofhighland mountainous rangeland of mount alborz range in iran. diversity and richnesswere assessed as an ecosystem health indicator. the study area was locate...

Based on the importance and role of species diversity and richness as ameasurement of the health of an ecosystem; studying of their components can lead toevaluate the health condition of rangeland. This research was carried out in a part ofhighland mountainous rangeland of Mount Alborz Range in Iran. Diversity and richnesswere assessed as an ecosystem health indicator. The study area was locate...

[1] Longitudinal and diel measurements of dual isotope composition (dN and dO) in nitrate (NO3-N) were made in the Ichetucknee River, a large ( 8 m s ), entirely spring-fed river in North Florida, to determine whether isotopic variation can deconvolve assimilatory and dissimilatory removal. Comparing nitrate concentrations and isotope composition during the day and night we predicted (1) daytim...

Edge effects are caused by the penetration of abiotic and biotic conditions from the matrix into forest interiors. Although edge effects influence the biogeography of many tropical organisms, they have not been studied directly in primates. Edge effects are particularly relevant to lemurs due to the loss of 80-90% of forests in Madagascar. In this study, data are presented on how biotic edge ef...

Sampling was done largely in the Dutch Kempen region located south-east of Eindhoven and north to a complex of several large zinc smelting works. Some samples were taken about 10 km north to this region in order to include data on less polluted sites. All sites were situated in either grassland or heathland on sandy podzolic soil. Thirty-one sites were sampled in total, mainly along transects o...

Although the so called "green islands" of the semi-arid Brazilian "Nordeste" are economically, socially, and ecologically important. relatively little is known about their biodiversity. We present the results of the first survey of the ground-dwelling ant fauna of a secondary forest in the Serra de Baturité (4 degrees 05'-4 degrees 40' S / 38 degrees 30'-39 degrees 10' W), among the biggest of ...

BACKGROUND AND AIMS The persistence of plants inhabiting restricted alpine areas under climate change will depend upon many factors including levels of genetic variation in adaptive traits, population structure, and breeding system. METHODS Using microsatellite markers, the genetic structure of populations of a relatively common alpine grass, Poa hiemata, is examined across three altitudinal ...

Microbes such as fungi and bacteria play fundamental roles in litter-decay and nutrient-cycling; however, their communities may respond differently than plants to climate change. The structure (diversity, richness, and evenness) and composition of microbial communities in climate transects of mature Douglas-fir stands of coastal British Columbia rainshadow forests was analyzed, in order to asse...

we studied 11 gaps covered with beech saplings (< 1.30 m tall) in a reserve compartment (compartment 139, district one, langa forest, watershed 36: kazemrood) of the caspian beech forest in n iran. two transects, each 2 m wide, were laid along the longest (n-s) and shortest (e-w) axis of each gap. five micro sample plots, each 4 m2, were established: one at the center, and one at each corner. q...

(Woody community dynamics in two fragments of “cerrado” stricto sensu over a seven-year period (1995-2002), MA, Brazil). This study was conducted in two fragments of “cerrado” stricto sensu in the Gerais de Balsas Colonization Project, located in southern Maranhão, Brazil. The objective was to evaluate the dynamics of the woody plant community, over seven years (1995-2002). Four transects of 16...