Remote controlled plant pore closure limits water loss

Author(s):  
Lara Reid
Keyword(s):  
Author(s):  
Michael T. Postek

Silicon occurs naturally in plants in the form of its hydrated oxide (SiO2.nH2O) commonly called silica. Silica has been shown to be a necessary element in the normal development of many plants, playing an array of roles including strengthening, protection, and reduction of water loss. Deposition of silica in various portions of the plant body, especially the leaves, may also be viewed as a way for the plant to dispose of any excess silica taken up beyond that necessary for normal metabolism.Studies of this “opaline” silica have thus far been limited to species of the Cyperaceae and Gramineae known to possess significant quantities of silica. Within the Magnoliaceae, certain “glistening” idioblast cells at the foliar veinlet termini and vein sheaths of Magnolia grandiflora (1) have been suspected to be siliceous in nature.


2012 ◽  
Vol 15 (3) ◽  
pp. 553-559 ◽  
Author(s):  
M.P. Szczepanik ◽  
P.M. Wilkołek ◽  
M. Pluta ◽  
Ł.R. Adamek ◽  
Z.J.H. Pomorski

Abstract The purpose of this study was to evaluate transepidermal water loss, skin hydration and skin pH in normal ponies. Sixteen ponies of both sexes were examined in the study. Measurements were taken from seven different sites: the neck region, the shoulder, thorax, lumbar, inguinal, lip region and the auricle. In each of the regions transepidermal water loss (TEWL), skin hydration and skin pH were measured. For transepidermal water loss, the lowest values were observed in the lumbar region (9.71g/hm2), while the highest values were observed in the lip region (22.35 g/hm2). In the case of skin hydration the lowest values were observed for the thorax region (2.13 CU), and the highest for the lip region (41.81 CU). For skin pH, the lowest results were obtained in the lumbar region (6.93), and the highest in the lip region (7.96).


1977 ◽  
Vol 69 (3) ◽  
pp. 419-424 ◽  
Author(s):  
A. S. Rogowski ◽  
E. L. Jacoby
Keyword(s):  

2003 ◽  
Vol 3 (1-2) ◽  
pp. 135-141 ◽  
Author(s):  
Z. Pilipovic ◽  
R. Taylor

In 1996, as part of Waitakere Council’s Water Cycle Strategy, a pressure standardisation programme to permanently lower the average supply pressure citywide was implemented with the aim of reducing water loss and water use. The experience gained during the 1994/95 Auckland water shortage had confirmed that there was considerable scope to reduce pressures in many areas. Since 1996 water pressures have been reduced in over 60% of the reticulated area of the city, with the average pressure reduced from 710 kPa to 540 kPa. As a result of this programme water loss from the network has been reduced, there has been a reduction in the frequency of mains breaks and it is likely that the life of water pipeline assets has been extended. Furthermore both pressure and demand management initiatives have reduced per capita water use in the city by more than 10%. A network computer model was used as a design tool to check the network under various pressure regimes and cost benefit analyses were carried out for various design scenarios. Fire sprinkler systems were checked as part of the design process. Minimum service standards were not reduced and in some cases pressures were actually increased. This paper covers the various aspects of the design, the implementation and the results of the pressure standardisation programme.


Author(s):  
Cristian Epifanio Toledo ◽  
João Carlos Mohn Nogueira ◽  
Alexandre De Amorim Camargo

The objective of this work was to propose and evaluate a model to estimate transit water losses and surface runoff in a Brazilian semi-arid basin, fundamental components in the hydrological studies of the region, such as in the verification of hydrological connectivity. The study area was the Orós Reservoir Basin, located in the state of Ceará. The modeling of transit water loss and surface runoff were developed based on the work of Araújo and Ribeiro (1996) and Peter et al. (2014). In the proposed model, the parameter of loss in transit (k) was estimated at 0.027 km-1 for a section of the river basin, and when simulated for other stretches it provided good flow results at the end of the stretch, obtaining an NSE of 82%. The value of the runoff coefficient was estimated at 3% and when evaluating a spatial variation of this coefficient in the basin, the values varied from 2% to 12%, and the use of specialized runoff coefficient (RC) values promoted a higher NSE in the discharge simulation in the basin. It is concluded that the proposed model to estimate transit water losses and surface runoff demonstrated a high efficiency in the simulation of hydrological processes. The basin of Orós reservoir presented a high variability of the coefficient of surface runoff, justifying the need for a greater spatiality of this coefficient in heterogeneous environments.


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