It was shown over 40 years ago that plants maximize carbon gain for a given rate of water loss if stomatal conductance, gs , varies in response to external and internal conditions such that the marginal carbon revenue of water, ∂A/∂E, remains constant over time. This theory has long held promise for understanding the physiological ecology of water use and for informing models of plant-atmospher...

in this study, to determine the economic value of irrigation water and simulate the response of farmers to reducing  available water policy of positive mathematical programming models (pmp) was used. by the proposed model, the economic value (shadow price) of irrigation water estimated in each of the areas of western rodbar alamuot, rajai dasht and eastern rodbar almuot. then, the reactions of ...

As the atmosphere warms, precipitation events are becoming less frequent but more intense. A three-year experiment in Kruger National Park, South Africa, found that fewer, more intense precipitation events encouraged woody plant encroachment. To test whether or not these treatment responses persisted over time, here, we report results from all five years of that experiment. Grass growth, woody ...

  Background: Although borage ( Borago officinalis L.) is a valuable medicinal plant, no information is available on the responses of this plant to salinity. For this reason, it is necessary to determine responses of this plant to salinity .  Objective: Since germination and early growth stage is one of the most critical phases of plant life under salinity condition this experiment was conducte...

Within European Union priorities, the problematic of available water sources have paid attention through the development of an integrated policy to reduce and control pressures and consequently leakage. In drinking pipe systems Pressure Reducing Valves (PRV) are used as dissipative devices for pressure control through a localized pressure drop. The use of microturbines or pumps operating as tur...

Plants are the most common bioindicatorsused in air quality biomonitoring studies because they are immobile and they have more sensitive to the most prevalent air pollutants than humans and animals. To identify the concentrations and sources of heavy metals in ornamental plants of Isfahan landscape, samples of leaves and soil around Pinuseldarica and Nerium oleander were collected at different ...

Herein we review the current state-of-the-art of plant hydraulics in the context of plant physiology, ecology, and evolution, focusing on current and future research opportunities. We explain the physics of water transport in plants and the limits of this transport system, highlighting the relationships between xylem structure and function. We describe the great variety of techniques existing f...

Chloride (Cl(-)) is a micronutrient that accumulates to macronutrient levels since it is normally available in nature and actively taken up by higher plants. Besides a role as an unspecific cell osmoticum, no clear biological roles have been explicitly associated with Cl(-) when accumulated to macronutrient concentrations. To address this question, the glycophyte tobacco (Nicotiana tabacum L. v...