QUANTIFYING WATER INFILTRATION INTO CORONADO CAVE AT CORONADO NATIONAL MEMORIAL, ARIZONA

2016 ◽  
Author(s):  
Brittiny Paige Moore ◽  
Keyword(s):  
2012 ◽  
Vol 8 (1) ◽  
pp. 37-48
Author(s):  
S. Chehaibi ◽  
K. Abrougui ◽  
F. Haouala

The effects of mechanical perforation densities by extracting soil cores through an aerator Vertidrain with a working width of 1.6 m and equipped with hollow tines spaced of 65 mm, were studied on a sandy soil of a grassy sward in the Golf Course El Kantaoui in Sousse (Tunisia). The mechanical aeration was performed at two densities: 250 and 350 holes/m2. The cone penetration resistance and soil water infiltration were measured. These parameters were performed at initial state before aeration (E0) and then on the 10th, 20th and 30th day after aeration. These results showed that perforation density of 350 holes/m2 had a positive effect on the soil by reducing its cone resistance to penetration compared to the initial state (Rp = 14.8 daN/cm2). At 5 cm depth the decrease in resistance to penetration was 34% and 43% on the 10th and 20th day after aeration, respectively. However, on the 30th day after aeration the soil resistance to penetration tended to grow and its value compared to the initial state decreased only by 21 and 26%, respectively, at 5 and 15 cm of depth only by 10% and 9% with 250 holes/m2 density. The soil water infiltration made a good improvement after aeration compared to the initial state. This parameter increased from 4.8 cm/h to 8.3, 10.9 and 13.1 cm/h with 250 holes/m2 density and to 10, 12.9 and 14.8 cm/h with 350 holes/m2 density on the 10th, 20th and 30th day following the aeration.


1955 ◽  
Vol 47 (5) ◽  
pp. 235-236 ◽  
Author(s):  
O. K. Barnes ◽  
D. W. Bohmont ◽  
Frank Rauzi

2021 ◽  
Vol 13 (5) ◽  
pp. 2432
Author(s):  
Anna Makarova ◽  
Elena Nikulina ◽  
Tatiana Avdeenkova ◽  
Ksenia Pishaeva

Heavy metals are among the most widespread pollutants in soil. Phytoextraction technology is used to solve the problem of multi-metal-contaminated soil. The efficiency of this process can be increased by introducing various amendments. A soil amendment is any material added to a soil to improve its physical properties, such as water retention, permeability, water infiltration, drainage, aeration, and structure. Some chemical amendments for enhanced phytoextraction, such as amino polycarboxylates chelators, can be hazardous to the environment and perform poorly at pH > 8. The effect of the potassium salt of hydroxyethylidene diphosphonic acid (K2HEDP), plant growth regulators (PGRs), and iron chelate alone and in combination on the phytoextraction by Trifolium repens L. seedlings of Cd, Ni, and Cu was studied in this work. K2HEDP works in a wider pH range. The results of this study confirmed that amino polycarboxylate chelators, with the sodium salt of ethylene diamine tetraacetic acid (Na2EDTA) as an example, have a pronounced negative effect on the growth and development (organ mass) of Trifolium repens L. seedlings. K2HEDP, proposed by the authors instead of Na2EDTA, produced a pronounced positive effect on plant growth and development, which was further enhanced by the use of PGRs and with iron chelates. However, it should be noted that K2HEDP showed significantly lower efficiency in trials on the Trifolium repens L. seedlings. The highest was the efficiency of K2HEDP with PGRs and iron chelates for the phytoextraction of Cd.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jiyu Sun ◽  
Wei Wu ◽  
Limei Tian ◽  
Wei Li ◽  
Fang Zhang ◽  
...  

AbstractNot only does the Dynastes tityus beetle display a reversible color change controlled by differences in humidity, but also, the elytron scale can change color from yellow-green to deep-brown in specified shapes. The results obtained by focused ion beam-scanning electron microscopy (FIB-SEM), show that the epicuticle (EPI) is a permeable layer, and the exocuticle (EXO) is a three-dimensional photonic crystal. To investigate the mechanism of the reversible color change, experiments were conducted to determine the water contact angle, surface chemical composition, and optical reflectance, and the reflective spectrum was simulated. The water on the surface began to permeate into the elytron via the surface elemental composition and channels in the EPI. A structural unit (SU) in the EXO allows local color changes in varied shapes. The reflectance of both yellow-green and deep-brown elytra increases as the incidence angle increases from 0° to 60°. The microstructure and changes in the refractive index are the main factors that influence the process of reversible color change. According to the simulation, the lower reflectance causing the color change to deep-brown results from water infiltration, which increases light absorption. Meanwhile, the waxy layer has no effect on the reflection of light. This study lays the foundation to manufacture engineered photonic materials that undergo controllable changes in iridescent color.


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