Germination response to extreme acidity: impact of simulated acid deposition from a single shuttle launch

Germinação de sementes de Erythrina speciosa Andr., Eugenia brasiliensis Lam. e Cucumis sativus L. em meio ácido

“…Alguns processos naturais são alterados pela acidez, como por exemplo, o entumescimento da semente, que depende do pH da solução (Zammit & Zedler 1988) ou o próprio metabolismo celular vegetal, que é dependente da concentração hidrogeniônica (Larcher 2000).…”

Examination of Metals from Aerospace-Related Activity in Surface Water Samples from Sites Surrounding the Kennedy Space Center (KSC), Florida

“…Typically, the solid rocket fuel is made up of aluminum powder (fuel), iron oxide (catalyst), ammonium perchlorate (oxidizer), and a polymer binder. , Postshuttle launch, the resultant exhaust plume has been shown to disperse several byproducts, most notably several gases (e.g., gaseous hydrogen chloride) and aluminum oxide (Al 2 O 3 ). − The amount of hydrogen chloride (or HCl upon hydration with water) and aluminum oxide generated from a shuttle launch can reach up to several thousand kilograms (in a 1 km 2 area), prompting several studies to examine its potential negative effect on the ecosystem at MINWR. − As a result of the high levels of HCl deposited into the local environment (mixing with over 190 000 L of water from exhaust), pH levels drop dramatically, with a concomitant increase in salinity (on average about 2 g/L). Postshuttle launch, the pH in water near launch pads has been recorded as low as 1.5 immediately following a launch. , Although the average measured pH level of the postlaunch surface water in this study was 6.13 (from 8.13 prelaunch for LC39A), 5.97 (from 8.40 prelaunch for LC39B), and 6.06 (down from 7.85 prelaunch), for the primary and secondary study (as shown in SI Tables S4 and S7), respectively; the pH value was most likely considerably lower immediately after the launch, as it has been reported that the neutralizing capabilities of the ecosystem surrounding LC39A can rebound the pH levels up to seven points in 24 h (SI Figure S4), due to the presence of limestone and seashells found in the substrate. Beyond the obvious detriment associated with a highly acidic environment, the lower pH values increase the solubility of metals.…”

“…Postshuttle launch, the pH in water near launch pads has been recorded as low as 1.5 immediately following a launch. 34,54 Although the average measured pH level of the postlaunch surface water in this study was 6.13 (from 8.13 prelaunch for LC39A), 5.97 (from 8.40 prelaunch for LC39B), and 6.06 (down from 7.85 prelaunch), for the primary and secondary study (as shown in SI Tables S4 and S7), respectively; the pH value was most likely considerably lower immediately after the launch, as it has been reported that the neutralizing capabilities of the ecosystem surrounding LC39A can rebound the pH levels up to seven points in 24 h (SI Figure S4), due to the presence of limestone and seashells found in the substrate.…”