scholarly journals Hydraulic conductance and the maintenance of water balance in flowers

2015 ◽  
Author(s):  
Adam B. Roddy ◽  
Craig R. Brodersen ◽  
Todd E. Dawson

AbstractFlowers face desiccating conditions, yet little is known about their ability to transport water. We quantified variability in floral hydraulic conductance (Kflower) for 20 species from 10 families and related it to traits hypothesized to be associated with liquid and vapor phase water transport. Basal angiosperm flowers had trait values associated with higher water and carbon costs than monocot and eudicot flowers. Kflower was coordinated with water supply (vein length per area, VLA) and loss (minimum epidermal conductance, gmin) traits among the magnoliids, but was insensitive to variation in these traits among the monocots and eudicots. Phylogenetic independent contrast (PIC) correlations revealed that few traits had undergone coordinated evolution. However, VLA and the desiccation time (Tdes), the quotient of water content and gmin, had significant trait and PIC correlations. The near absence of stomata from monocot and eudicot flowers may have been critical in minimizing water loss rates among these clades. Early-divergent, basal angiosperm flowers maintain higher Kflower due to traits associated with high rates water loss and water supply, while monocot and eudicot flowers employ a more conservative strategy of limiting water loss and may rely on stored water to maintain turgor and delay desiccation.

Water ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1433
Author(s):  
Navneet Kumar ◽  
Asia Khamzina ◽  
Patrick Knöfel ◽  
John P. A. Lamers ◽  
Bernhard Tischbein

Climate change is likely to decrease surface water availability in Central Asia, thereby necessitating land use adaptations in irrigated regions. The introduction of trees to marginally productive croplands with shallow groundwater was suggested for irrigation water-saving and improving the land’s productivity. Considering the possible trade-offs with water availability in large-scale afforestation, our study predicted the impacts on water balance components in the lower reaches of the Amudarya River to facilitate afforestation planning using the Soil and Water Assessment Tool (SWAT). The land-use scenarios used for modeling analysis considered the afforestation of 62% and 100% of marginally productive croplands under average and low irrigation water supply identified from historical land-use maps. The results indicate a dramatic decrease in the examined water balance components in all afforestation scenarios based largely on the reduced irrigation demand of trees compared to the main crops. Specifically, replacing current crops (mostly cotton) with trees on all marginal land (approximately 663 km2) in the study region with an average water availability would save 1037 mln m3 of gross irrigation input within the study region and lower the annual drainage discharge by 504 mln m3. These effects have a considerable potential to support irrigation water management and enhance drainage functions in adapting to future water supply limitations.


2013 ◽  
Vol 5 (3) ◽  
pp. 364-370 ◽  
Author(s):  
Elnaz SOLEIMANY-FARD ◽  
Khodayar HEMMATI ◽  
Ahmad KHALIGHI

Keeping quality and length of vase life are important factors for evaluation of cut flowers quality, for both domestic and export markets. Studding the effect of pre- and post-harvest salicylic acid applications on keeping quality and vase life of cut alstroemeria flowers during vase period is the approach taken. Aqueous solutions of salicylic acid at 0.0 (with distilled water), 1, 2 and 3 mM were sprayed to run-off (approximately 500 mL per plant), about two weeks before flowers harvest. The cut flowers were harvested in the early morning and both of cut flowers treated (sprayed) and untreated were kept in vase solutions containing salicylic acid at 0.0 (with distilled water), 1, 2 and 3 mM. Sucrose at 4% was added to all treatments as a base solution. The changes in relative fresh weight, water uptake, water loss, water balance, total chlorophyll content and vase life were estimated during vase period. The results showed that the relative fresh weight, water uptake, water balance, total chlorophyll content and vase life decreased significantly while the water loss increased significantly during experiment for all treatments. A significant difference between salicylic acid and control treatments in all measured parameters is observed. During vase period, the salicylic acid treatments maintained significantly a more favourable relative fresh weight, water uptake, water balance, total chlorophyll content and supressed significantly water loss, as compared to control treatment. Also, the results showed that the using salicylic acid increased significantly the vase life cut alstroemeria flowers, over control. The highest values of measured parameters were found when plants were treated by pre + post-harvest application of salicylic acid at 3 mM. The result revealed that the quality attributes and vase life of cut alstroemeria flowers were improved by the use of salicylic acid treatment.


2013 ◽  
Vol 16 (1) ◽  
pp. 49-57
Author(s):  
Tuan Anh Vo

The HCMC water supply system have built from the French Colonial period, and developed without planning and systematic study during the war time. In the beginning, this system used for the small town Saigon- Gia Dinh. Today, the capacity of water supply system is 1,85 million m3/day and will increase up to 2,5 million in next few year and up to 4-5 million m3/day according with the HCMC water supply system planning approved by Government. The climate change issues, salt water lever increase, polution... affect directly into the raw water resource of the existing and future water treatment plant. Beside that, the big size water supply transmission pipe line and the distribution water supply system of 06 hydrolique zone in HCMC damaged according with time : bad quality and No- update information of pipe system… It bring the real water loss level in HCMC so high up to 40% - 50% .The acceptable technologies & techniques solution to find the leak, optimal management for the water supply system to reduce the water loss is extremely essential, to support the clean water resources for the sustainable development of the HCM City.


2001 ◽  
Vol 204 (13) ◽  
pp. 2331-2338 ◽  
Author(s):  
Allen G. Gibbs ◽  
Luciano M. Matzkin

SUMMARYFruit flies of the genus Drosophila have independently invaded deserts around the world on numerous occasions. To understand the physiological mechanisms allowing these small organisms to survive and thrive in arid environments, we performed a phylogenetic analysis of water balance in Drosophila species from different habitats. Desert (cactophilic) species were more resistant to desiccation than mesic ones. This resistance could be accomplished in three ways: by increasing the amount of water in the body, by reducing rates of water loss or by tolerating the loss of a greater percentage of body water (dehydration tolerance). Cactophilic Drosophila lost water less rapidly and appeared to be more tolerant of low water content, although males actually contained less water than their mesic congeners. However, when the phylogenetic relationships between the species were taken into account, greater dehydration tolerance was not correlated with increased desiccation resistance. Therefore, only one of the three expected adaptive mechanisms, lower rates of water loss, has actually evolved in desert Drosophila, and the other apparently adaptive difference between arid and mesic species (increased dehydration tolerance) instead reflects phylogenetic history.


2021 ◽  
Vol 16 (1) ◽  
pp. 18-25
Author(s):  
Fauziah Ismahyanti ◽  
Rosmawita Saleh ◽  
Arris Maulana

This research is done to plan rainwater harvesting so that it can be used as an alternative water source on the campus B UNJ so it is expected to reduce groundwater use that can cause a puddle. The method used in the PAH development plan is a water balance method. This method compares the level of demand with water volume that can be accommodated or the availability of water (supply). Based on the results of the analysis, it was found that the potential for rainwater in the FIO office building A was 1773.95 m3 , FMIPA building B was 1904.62 m3 , the FIO lecture building C was 1613.21 m3 and the Ulul Albab mosque was 512.16 m3 . Potential rainwater obtained cistern PAH capacity of 200 m3 by saving water needs by 30% in building A FIO, building B FMIPA, and building C FIO. The capacity of the PAH cistern is 80 m3 by saving the water needs of the Ulul Albab mosque by 13.3%. Placement of the PAH cistern under the ground with a ground water system. Ecodrainage application by utilizing the PAH system can reduce drainage load by 0.158 m3 /second or 13.9% from rainwater runoff.


1991 ◽  
Vol 23 (10-12) ◽  
pp. 1825-1833
Author(s):  
D. R. McGrath ◽  
G. E. Ho ◽  
K. Mathew

The potential usage of Evapotranspiration (ET) systems in remote Aboriginal communities was investigated. ET system sizing requirements were determined from the water balance equation. Water loss from lysimeters planted with trees (Eucalyptus camaldulensis) or lawn grass and from bare soil and gravel was monitored over several months and compared to pan evaporation measured during the same period. It was found that ET from bare soil and grass followed similar trends to pan evaporation, ranging from 30-60% of pan evaporation for soil and from 60-80% of pan evaporation for grass. ET rates increased in the tanks planted with trees as the plants grew and exceeded pan evaporation rates. Evaporation from gravel-filled lysimeters was low, being as little as 10% of pan evaporation.


Water ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 720 ◽  
Author(s):  
Yolanda Cantón ◽  
Sonia Chamizo ◽  
Emilio Rodriguez-Caballero ◽  
Roberto Lázaro ◽  
Beatriz Roncero-Ramos ◽  
...  

Arid and semi-arid ecosystems are characterized by patchy vegetation and variable resource availability. The interplant spaces of these ecosystems are very often covered by cyanobacteria-dominated biocrusts, which are the primary colonizers of terrestrial ecosystems and key in facilitating the succession of other biocrust organisms and plants. Cyanobacterial biocrusts regulate the horizontal and vertical fluxes of water, carbon and nutrients into and from the soil and play crucial hydrological, geomorphological and ecological roles in these ecosystems. In this paper, we analyze the influence of cyanobacterial biocrusts on water balance components (infiltration-runoff, evaporation, soil moisture and non-rainfall water inputs (NRWIs)) in representative semiarid ecosystems in southeastern Spain. The influence of cyanobacterial biocrusts, in two stages of their development, on runoff-infiltration was studied by rainfall simulation and in field plots under natural rainfall at different spatial scales. Results showed that cover, exopolysaccharide content, roughness, organic carbon, total nitrogen, available water holding capacity, aggregate stability, and other properties increased with the development of the cyanobacterial biocrust. Due to the effects on these soil properties, runoff generation was lower in well-developed than in incipient-cyanobacterial biocrusts under both simulated and natural rainfall and on different spatial scales. Runoff yield decreased at coarser spatial scales due to re-infiltration along the hillslope, thus decreasing hydrological connectivity. Soil moisture monitoring at 0.03 m depth revealed higher moisture content and slower soil water loss in plots covered by cyanobacterial biocrusts compared to bare soils. Non-rainfall water inputs were also higher under well-developed cyanobacterial biocrusts than in bare soils. Disturbance of cyanobacterial biocrusts seriously affected the water balance by increasing runoff, decreasing soil moisture and accelerating soil water loss, at the same time that led to a very significant increase in sediment yield. The recovery of biocrust cover after disturbance can be relatively fast, but its growth rate is strongly conditioned by microclimate. The results of this paper show the important influence of cyanobacterial biocrust in modulating the different processes supporting the capacity of these ecosystems to provide key services such as water regulation or erosion control, and also the important impacts of their anthropic disturbance.


1979 ◽  
Vol 57 (10) ◽  
pp. 1863-1865 ◽  
Author(s):  
Roger M. Evans

Seawater-adapted teleosts drink to offset water loss by osmosis. A direct method of monitoring drinking by implanting a fistula to drain the stomach indicated that rainbow trout began drinking from about 9 to 12 (range 1 to 22) h after being placed in 15‰ sea water. Unlike the Japanese eel (Anguilla japonica). in which the onset of drinking has been shown to be immediate and reflex-like, the onset of drinking in trout appears to occur only after appreciable water has been lost to the medium. The trout resembles the eel in that the capacity to shallow water in the absence of postingestional negative feedback exceeds the rate of drinking required to maintain normal water balance.


Sign in / Sign up

Export Citation Format

Share Document