moisture gradient
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Author(s):  
Aditya Prajapati ◽  
Rohan Sartape ◽  
Tomás Rojas ◽  
Naveen K. Dandu ◽  
Pratik Dhakal ◽  
...  

An ultrafast, continuous CO2 capture process driven by moisture gradient and electric field with low energy consumption to capture and concentrate CO2 from dilute sources.


Author(s):  
Edwin-Wosu Nsirim Lucky ◽  
Omara-Achong Theresa Ebia ◽  
Idogun Ejiro Praise

Background: Knowledge of the anatomy of Anthocleista species is crucial for understanding how these plants adapt to the environment. Aim: This study was aimed at investigating the adaptive relationship of moisture gradient influence on the anatomy of four species in the genus Anthocleista (A djalonesis A Chev; A.  liebrechtsiana De Wild & Th.Dur; A. nobilis G.Don; and A. vogelii Planch) in light of ecological niche adaptation. Place of Study: parts of Akwa-Ibom, Bayelsa, Cross River and Rivers States in the Niger Delta. Methods: Conventional classical anatomical techniques for structural sectioning were used. Results: Though there are similarities and differences in vascular structure among the species, the study has revealed variance in anatomical responses to moisture gradient (ranging from dry mesophytic to mesophytic and wetland conditions) of adaptation. The most important and distinct features observed are the presence of sclerenchymatous idioblast, air sacs and sclereidal idioblast. Sclerenchymatous idioblasts are numerous in A liebrechtsiana, few in A.  nobilis and A. vogelii but lacking in A. djalonesis. The sclerenchymatous idioblast in A. liebrechtsiana, A. nobilis, and A. vogelii confirmed these species to be mesophytic to semi-aquatic in their habitat adaptation; while A. djalonesis is dry-mesophytic in adaptation with thicker epidermal layer, multiple hypodermal layers, thicker mesophyll tissues with increased number of palisade layers and thick leaves. The stem and root modification had abundance sclereidal idioblast distribution in A. liebrechtsiana, and A. nobilis, moderate in A. vogelii and very low in A. djalonesis. Conclusion: The variation observed in the leaf, petiole, stem and root anatomical characters are due to moisture gradient influence with the resultant effect of plant species evolving structures such as idioblast and modification to adapt to the niche and environment where they find themselves.


2021 ◽  
pp. 1-71
Author(s):  
Adam H. Sobel

Abstract The Madden Julian Oscillation (MJO) and the Boreal Summer Intraseasonal Oscillation (BSISO) are fundamental modes of variability in the tropical atmosphere on the intraseasonal time scale. A linear model, using a moist shallow water equation set on an equatorial beta plane, is developed to provide a unified treatment of the two modes and to understand their growth and propagation over the Indian Ocean. Moisture is assumed to increase linearly with longitude and to decrease quadratically with latitude. Solutions are obtained through linear stability analysis, considering the gravest (n = 1) meridional mode with nonzero meridional velocity. Anomalies in zonal moisture advection and surface fluxes are both proportional to those in zonal wind, but of opposite sign. With observation-based estimates for both effects, the zonal advection dominates, and drives the planetary-scale instability. With a sufficiently small meridional moisture gradient, the horizontal structure exhibits oscillations with latitude and a northwest-southeast horizontal tilt in the northern hemisphere, qualitatively resembling the observed BSISO. As the meridional moisture gradient increases, the horizontal tilt decreases and the spatial pattern transforms toward the “swallowtail” structure associated with the MJO, with cyclonic gyres in both hemispheres straddling the equatorial precipitation maximum. These results suggest that the magnitude of the meridional moisture gradient shapes the horizontal structures, leading to the transformation from the BSISO-like tilted horizontal structure to the MJO-like neutral wave structure as the meridional moisture gradient changes with the seasons. The existence and behavior of these intraseasonal modes can be understood as a consequence of phase speed matching between the equatorial mode with zero meridional velocity (analogous to the dry Kelvin wave) and a local off-equatorial component that is characterized by considering an otherwise similar system on an f-plane.


2021 ◽  
Vol 25 (7) ◽  
pp. 1201-1206
Author(s):  
A.U. Jibo

There had been a discernible shift in climate affecting the Sahelian zone of northern Nigeria. This attribute of drought influenced the rate of gum Arabic production in the North eastern axis. Therefore, these called for the studied of the Influence of drought on Acacia senegal (L.) Willd. Gum yield within a Soil moisture gradient in north eastern Nigeria. Two studied areas were purposively selected based on the availability (Gujba and Nguru). Complete Randomised Design was employed with three (3) samples examined at six (6) levels in six different tapping periods. Also, systematic line transect of 1Km was laid at the middle of both plantations where 1m by 1m transect were further laid in four transect sample plots. The soil samples were collected with the aid of soil auger at different levels (0-25 cm, 25-50 cm, 50-75 cm, 75-100 cm, 100-150 cm, 150-200 cm). Data was subjected using analysis of variance with statistical analysis system and descriptive statistic was also employed. The results showed that mean yield of Gum Arabic is Gujba is higher than Nguru (45kg and 30kg) respectively. Furthermore, physiochemical properties showed that pH, aluminium calcium and magnesium in both plantations were very high which is harmful for plantation development. Therefore, there is need for proper conservation and silvicultural management for both study areas.


2021 ◽  
Author(s):  
◽  
Justis Henault ◽  

The Poweshiek skipperling (Oarisma poweshiek) is endemic to the tall grass prairie in North America, and is now critically endangered globally. Existing populations are scattered amongst tall grass prairie remnants. However, the host food plants eaten by Poweshiek skipperling larvae, the vegetative and microclimatic descriptions of immature and adult microhabitats as well as O. poweshiek behaviour in Manitoba are unknown. I observed the foraging behaviour of larval O. poweshiek in natural habitat to determine the plant species that they consume and document their development. I also followed adults in prairie patches to identify locations in which various activities, such as egg laying or nectar feeding, were facilitated by the habitat. I measured vegetative, structural and microclimatic attributes of microhabitats to determine potential characteristics which facilitate various adult activities and larval development. Larvae appeared to navigate microhabitats to locate host food plant species, alternating between shoots of various species throughout their development. Adults flew almost exclusively in the prairie plant community, rarely flew in shrub or ephemeral wetland communities and were never observed flying in wetland or forest communities. Adult activities appeared to be distributed along a soil moisture gradient, with egg laying associated with the mesic section of the moisture gradient, resting and/or basking associated with the drier section and nectar feeding generally associated with sections throughout the moisture gradient. My research contributes knowledge about larval O. poweshiek foraging and adult habitat interactions in prairies in Manitoba, Canada. Discoveries from my research may guide habitat stewardship to ensure that high quality habitat is available for every life stage and inform reintroduction activities to ensure potential release locations contain required habitat features. Novel descriptions of locations which facilitate larval development and various adult activities may inform provincial and federal recovery strategies to increase the chances of O. poweshiek’s survival. My findings may also initiate further research about the Poweshiek skippering and possibly guide the strategies to recover other Lepidopterans-at-risk. Now with a greater understanding of larval foraging and adult interactions, we may hopefully generate potential causes which explain O. poweshiek’s decline and identify possible solutions to facilitate its successful recovery!


2021 ◽  
Author(s):  
Matthew C. I. Medeiros ◽  
Priscilla S. Seabourn ◽  
Randi L. Rollins ◽  
Nicole M. Yoneishi

BioTechniques ◽  
2021 ◽  
Vol 71 (4) ◽  
pp. 516-527
Author(s):  
Mery Nair Sáenz-Rodríguez ◽  
Gladys Iliana Cassab López

We designed and validated a test system that simulates a growth environment for  Zea mays L. maize seedlings under conditions of low moisture gradient in darkness. This system allowed us to simultaneously measure mesocotyl elongation and the primary root hydrotropic response in seedlings before the emergence phase in a collection of maize hybrids. We found great variation in these two traits with statistically significant reduction of their elongations under the low moisture gradient condition that indicate the richness of maize genetic diversity. Hence, the objective of designing a new test system that evaluates the association between these underground traits with the potential use to measure other traits in maize seedlings related to early vigor was achieved.


2021 ◽  
Vol 10 (2) ◽  
pp. 164
Author(s):  
N. M. Nde ◽  
D. Fokwa ◽  
M. Mbessa ◽  
T. T. Tamo ◽  
C. Pettang

The sometimes extreme hydro-climatic stresses that buildings undergo can lead to significant deterioration which can lead to their collapse. The concern to realize durable works and ensuring a comfortable framework for the life of occupants leads to seek effective solutions, as well for the new construction as for the renovation of old construction, answering the sempiternal problem of harmful action of water on buildings materials. This paper proposes a numerical simulation of moisture migration in concrete building walls, the aim being to highlight the influence of pore size on the kinetics of moisture migration, and its gradient in the wall. A mathematical model taking into account the mechanisms of moisture migration due to liquid moisture gradient and by vapor diffusion is proposed; the discrete formulation of the equa-tion by the numerical scheme of Crank Nicolson is then carried out, and results from computer modeling using Matlab software version 7.10.0.499 (R2010a), show that pore size is a key parameter that influences the dynamics of moisture migration in the wall. Indeed, this parameter qualitatively and quantitatively influences the kinetics of moisture migration, as well as it gradient in the concrete wall. It appears a greater migration dynamic when the pores sizes decrease, means a greater kinetics of moisture migration and lower moisture gradient in the walls at the hygrometric equilibrium, for a decreasing pore size. 


Author(s):  
J Grey Monroe ◽  
Haoran Cai ◽  
David L Des Marais

Abstract Water availability is perhaps the greatest environmental determinant of plant yield and fitness. However, our understanding of plant-water relations is limited because—like many studies of organism-environment interaction—it is primarily informed by experiments considering performance at two discrete levels—wet and dry—rather than as a continuously varying environmental gradient. Here, we used experimental and statistical methods based on function-valued traits to explore genetic variation in responses to a continuous soil moisture gradient in physiological and morphological traits among 10 genotypes across two species of the model grass genus Brachypodium. We find that most traits exhibit significant genetic variation and nonlinear responses to soil moisture variability. We also observe differences in the shape of these nonlinear responses between traits and genotypes. Emergent phenomena arise from this variation including changes in trait correlations and evolutionary constraints as a function of soil moisture. Our results point to the importance of considering diversity in nonlinear organism-environment relationships to understand plastic and evolutionary responses to changing climates.


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