Search results for "Water use efficiency."
showing 4 items of 14 documents
Effects of Saline and Deficit Irrigation on Soil-Plant Water Status and Potato Crop Yield under the Semiarid Climate of Tunisia
2019
Water supplies have been decreasing in several semi-arid regions, and it is therefore necessary to adopt irrigation strategies aimed at maximizing water use efficiency. In this paper, the effects of saline and deficit irrigation on water use efficiency and on potato crop response, based on observations of soil and plant water status, were investigated. Experiments were carried out in Central Tunisia, by monitoring potato crop growth during two seasons in four distinct treatments (T1&ndash
Physiological,anatomical and biomass partitioning responses to ozone in the Mediterranean endemic plant Lamottea dianae
2011
Ozone effects on the perennial forb Lamottea dianae were studied in an open-top chamber experiment. Ozone was found to induce reductions in CO 2 assimilation and water use efficiency in the leaves of this species. These reductions were mainly related to a decline in the in vivo CO 2 fixation capacity of Rubisco (V c,max), rather than to stomatal limitations or photoinhibitory damage (F v:F m). In addition to chloroplast degeneration, other observed effects were callose accumulation, formation of pectinaceous wart-like cell wall exudates and phloem alterations. Moreover, ozone exposure significantly reduced root dry biomass. The possible relevance of these adverse effects for Mediterranean f…
Subsurface drip irrigated potato (Solanum tuberosum L.) with saline water under Tunisian climate
2012
Field experiment was conducted at the Higher Institute of Agronomy of Chott Meriem (Tunisia) during the growing season (2011/2012) to investigate the effects of water quality on water‘s dynamic in soil (water potential, soilcmoisture distribution, water’s stock in soil) and water use efficiency (WUE) to produce potato (Solanum tuberosum L.). Irrigation management treatments were fresh (1 dS m-1) and saline waters (4 dS m-1). Subsurface drip irrigation was used, a rate of 4 L h-1 applied at the same irrigation duration and interval. The results indicate that water content is more uniform using the saline water varies from 15 to 23% than treatment varies from 10 to 26%. The recorded changes o…
Compared regimes of NDVI and Rainfall in semi-arid regions of Africa
2006
International audience; Bi-monthly normalized difference vegetation index (NDVI) at an 8km spatial resolution from the advanced very high resolution radiometers (AVHRR) was used from 1981 to 1995 to analyse the vegetation response to rainfall supply in semi-arid regions of Africa. Within the 200-600 mm annual rainfall belt, for which the apparent NDVI response to rainfall was the strongest, three regions were selected which exhibited different patterns in their NDVI regimes and/or relationships with rainfall. The regions, located in western, southern and eastern Africa, were split into coherent sub-regions in terms of mean regime of photosynthetic activity through a cluster analysis. Overal…