Overgrazing affects plant communities, and is a significant disturbance factor in arid and semi-arid regions. The immediate changes of plant communities after overgrazing in the disturbed arid ecosystems of Iran have been poorly studied. We recorded data from 100 random samples before and after overgrazing in the Golbahar plain located in the northeastern Iran to determine the changes in the pl...

Understanding the mechanisms underlying negative plant-soil feedbacks remains a critical challenge in plant ecology. If closely related species are more similar, then phylogeny could be used as a predictor for plant species interactions, simplifying our understanding of how plant-soil feedbacks structure plant communities, underlie invasive species dynamics, or reduce agricultural productivity....

Abstract Over the last fifty years, most of the semi-arid rangeland in Iran has been converted to cropland without an equivalent reduction in grazing animals. This shift has led to heavy grazing pressure on rangeland vegetation. The present study has been conducted in Sisab Research Station in the North Khorasan Province to evaluate effects of long-term grazing exclosures on biodiversity of ra...

Fourteen plant species collected in Iran and selected mainly on the basis of their antimicrobial and/or antifungal activities were evaluated for in vitro antiplasmodial and cytotoxic effects in a study designed to screen plant extracts with selective activity against Plasmodium falciparum. The methanol extracts of nine of the species tested exhibit activity against Plasmodium falciparum (MIC va...

Because arbuscular mycorrhizal fungal (AMF) species differ in stimulating the growth of particular host plant species, AMF species may vary in their effects on plant intra-specific competition and the self-thinning process. We tested this hypothesis using a microcosm experiment with Medicago sativa L. as a model plant population and four AMF species. Our results showed that the AMF species Glom...

ETHNOPHARMACOLOGICAL RELEVANCE Sri Lanka has a great diversity of snake species. In this relation, over 40,000 cases of snakebite accidents are reported annually from different agro-ecological regions of the country. Since more than 95% of victims rely on traditional treatments, there is an urgent necessity to improve the system. Traditional knowledge on snakebite treatments has been passed on ...

Silvicultural operation need to notice the species diversity. To this study Gomarlang district in marivan region, northern zagros forest was selected. In this study 30 circle sample plots (500 m2) were collected by random method. In every sample plot the kind of species and number of trees and shrub were recorded. In the sample plots the micro plots of 5 m by 5 m (i.e. area of 25 m2) were desig...

Traits that permit successful invasions have often seemed idiosyncratic, and the key biological traits identified vary widely among species. This fundamentally limits our ability to determine the invasion potential of a species. However, ultimately, successful invaders must have positive growth rates that longer term result in higher biomass accumulation than competing established species. In m...

To determine how plant species richness impacts microbial assimilation of new photosynthate, and how this may be modified by atmospheric N deposition, we analyzed the microbial assimilation of recent photosynthate in a 6-year-long field experiment in which plant species richness, atmospheric N deposition, and atmospheric CO2 concentration were manipulated in concert. The depleted dC of fumigati...

This paper aims to throw light on the mass extinction that is overtaking Earth's species. Using an analytic methodology developed for an earlier partial assessment, it focuses on a series of "hotspot" areas, these being areas that a) feature exceptional concentrations of species with high levels of endemism and b) face exceptional threats of destruction. The paper identifies another 8 such ar...