Water harvesting systems have improved productivity in various regions in sub-Saharan Africa. Similarly, they can help retain water in landscapes, build resilience against droughts and dry spells, and thereby contribute to sustainable agricultural intensification. However, there is no strong empirical evidence that shows the effects of intensification of water harvesting on upstream-downstream ...

in order to investigate the effect of irrigation intervals and harvesting time on yield and yield components of anise (pimpinella anisum l.) a field experiment was conducted at the agricultural research station, university of zanjan in 2010. for this purpose a spilt-plot experiment based on complete randomized block design with three replications was used. three irrigation intervals (every 7, 1...

Phytoplankton distribution is relatively constant in large areas of the surface ocean. In order to maintain this apparent stability, phytoplankton production and losses have to be balanced. Indeed, growth (μo) and grazing (g) rates obtained simultaneously with the dilution technique are often tightly coupled. One problem with this approach is that growth and grazing are not independent in the e...

Miombo woodlands are crucial to the livelihoods of rural people throughout southern, eastern and central Africa. This paper describes a dynamic simulation model of key ecological processes in miombo and examines the ecological and economic impacts of various forms of management. The model shows that removing harvestable trees and reducing the level of grazing by livestock causes an increase in ...

conservation tillage, a fast growing practice in iran, is considered as a means to achieve sustainability in agricultural systems. this study was carried out to determine the effect of tillage systems (no-tillage, minimum tillage and conventional tillage ) on yield and yield components of three irrigated wheat varieties. the field experiment was conducted at the experimental station of the univ...

In this paper it is shown that the sub-supersolution method works for age-dependent diffusive nonlinear systems with non-local initial conditions. As application, we prove the existence and uniqueness of positive solution for a kind of Lotka-Volterra systems, as well as the blow-up in finite time in a particular case.