Forests are complex ecosystems that develop over centuries through the interactions between organisms and biogeochemical cycles of elements occurring in the soil-atmosphere continuum. The biomass and structure of a forest stand is involved in several ecosystem processes and has been used as an indicator of forest health and productivity. The forest biomass is a key component of the carbon cycle...

drought is a major limiting factor for agricultural production in most parts of the world and landraces areimportant genetic resources for crop improvement in dry areas. during the 2007-2008 cropping season, 23 chickpea (cicer arietinum l.) genotypes consisting of 21 kabuli chickpea landraces provided by the national plant gene bank of iran and two known commercial varieties (hashem and arman) ...

The goal of sustainable agriculture is to maintain a non-negative trend in productivity while maintaining soil quality. Our main objective was to determine the sustainability of organic cropping systems. Three of the selected farms were in organic production for three, six and nine years since certification, and a fourth in conventional production. We found significant relationships between som...

The basic ecology of seagrass beds was investigated by comparing biomass, productivity and density of Thalassia testudinum (turtle grass) at three sites: Puerto Vargas, Punta Cahuita and Rio Perezoso, in Cahuita National Park, Limón, Costa Rica, over a two month period (March-April 1999). Above ground biomass, density, and productivity were highest in the Puerto Vargas site while Punta Cahuita ...

Fodder trees and shrubs are crucial sources of animal feed in Sudan, particularly in arid and semi-arid areas. This is because they can fill up the feed gaps in the summer period when grassland growth is limited due to unfavorable weather conditions. The study was conducted in Elnour forest-southeastern Sudan in 2015, which is dominated by Acacia seyal. The objectives of this study were to esti...

Ultraviolet-B (UV-B) radiation and elevated tropospheric ozone may cause reductions in the productivity and quality of important agricultural crops. However, research regarding their interactive effect is still scarce, especially on the belowground processes. Using the open top chambers experimental setup, we monitored the response of soil nematodes to the elevated O3 and UV-B radiation individ...

Dynamic vegetation models forced with spatially homogeneous biophysical parameters are capable of producing average productivity and biomass values for the Amazon basin forest biome that are close to the observed estimates, but these models are unable to reproduce observed spatial variability. Recent observational studies have shown substantial regional spatial variability of above-ground produ...

The effects of grazing and nutrients on epiphyte biomass in seagrass beds have received much attention, yet less is known about effects on other metrics of epiphyte growth dynamics, such as epiphyte productivity and biomass turnover rates. To help address this gap, we present here a number of mesocosm experiments in which we manipulate grazer presence and nutrient concentrations under initially...