Plant physiology water uptake

Weather ley, P.E. 1982. Water uptake and flow in roots. In Lange, O.L., Nobel, P.S., Osmond, C. B., and Ziegler, H. (Eds.), Physiological Plant Ecology, Encyclopedia of Plant Physiology, New Series. Vol. 12B. Springer Verlag, Berlin, pp. 79-109. 

Figure 23.2.5. Phytoremediation transport modes for HC and CHC in plant systems. Transformation of HC and CHC can be found in the root system with root-associated microbes and tissues of many plant species. HC and CHC are transported by normal plant physiological processes, such as water uptake and evaporation and transpiration. [Schematic courtesy M.A. Bucaro.]...

Manz, B., Muller, K, Kucera, B., Volke, F. Leubner-Metzger, G. (2005). Water Uptake and Distribution in Germinating Tobacco Seeds Investigated in Vivo by Nuclear Magnetic Resonance Imaging. Plant Physiology, Vol. 138, No. 3 0uly 2005), pp. 1538-1551, ISSN 1532-2548... 

The major function of cutin is to serve as the structural component of the outer barrier of plants. As the major component of the cuticle it plays a major role in the interaction of the plant with its environment. Development of the cuticle is thought to be responsible for the ability of plants to move onto land where the cuticle limits diffusion of moisture and thus prevents desiccation [141]. The plant cuticle controls the exchange of matter between leaf and atmosphere. The transport properties of the cuticle strongly influences the loss of water and solutes from the leaf interior as well as uptake of nonvolatile chemicals from the atmosphere to the leaf surface. In the absence of stomata the cuticle controls gas exchange. The cuticle as a transport-limiting barrier is important in its physiological and ecological functions. The diffusion across plant cuticle follows basic laws of passive diffusion across lipophylic membranes [142]. Isolated cuticular membranes have been used to study this permeability and the results obtained appear to be valid... 

The uptake of organic contaminants by plants from biosolids-amended soil depends on the physicochemical properties of organic compoimds and the physiology of plants [92-95]. Plant uptake of organic chemicals and their distribution within plants have been shown to be affected by (1) the organic chemicals physicochemical properties, including solubility, vapor pressure, octanol-water partition coefficient Kow)> and Henry s law constants (iC ), (2) environmental conditions such as temperature, air disturbance and soil organic matter content, and (3) plant characteristics, for example the shape of the leaves, type of root system, and lipid and cuticle characteristics and contents [94]. 

Particulate matter may physically become a factor in leaf physiological function if deposition is heavy enough to block light (critical to the photosynthetic machinery of the leaf) or if stomata become occluded by the particles. In the latter case both uptake of carbon dioxide for photosynthesis and water loss by the plant could be reduced. Particulate matter also has a potential to chemically alter the micro-environment of the leaf surface. Trace concentrations of heavy metals associated with deposited particles, as well as strong acid anions, may significantly modify the chemical nature of water drops or films of water in contact with plant surfaces. 

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