Author
![]() |
ZHELJAZKOV, VALTCHO - University Of Wyoming |
![]() |
Cantrell, Charles |
![]() |
ASTATKIE, TESS - Dalhousie University |
![]() |
SCHLEGEL, VICKI - University Of Nebraska |
![]() |
JELIAZKOVA, EKATERINA - University Of Wyoming |
![]() |
LOWE, DEREK - University Of Wyoming |
Submitted to: Journal of Environmental Quality
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 12/1/2013 Publication Date: 6/25/2014 Citation: Zheljazkov, V.D., Cantrell, C.L., Astatkie, T., Schlegel, V., Jeliazkova, E., Lowe, D. 2014. The effect of coal-bed methane water on spearmint and peppermint. Journal of Environmental Quality. 42:1815-1821. Interpretive Summary: Coal bed methane (CBM) is naturally occurring methane, enclosed in coal seams, flooded with water. To facilitate extraction of CBM, the water in the coal seams has to be pumped out. While the quality of CBM water (CBMW) may vary significantly, some research has demonstrated its feasibility for irrigation of rangelands or re-vegetation and reclamation of disturbed lands. Major concerns with the use of CBMW are the high concentrations of S, Na, and salts. The objective of this study was to evaluate the effect of various levels of CBMW on the growth, essential oil content, composition and antioxidant activity of spearmint and peppermint. The treatments were: 0% CBMW (control, tap water only), 25% (25% CBMW plus 75% tap water), 50% CBMW (half CBMW and half tap water), 75% CBMW (75% CBMW plus 25% tap water), and 100% CBMW. CBMW treatments did not affect the antioxidant capacity of spearmint or peppermint essential oil, and their major oil constituents, carvone or menthol, respectively. CBMW at 100% increased total phenols and total flavonoids in peppermint, but not in spearmint. CBMW at 25% increased fresh herbage yields of spearmint, but not in peppermint. Native spearmint and peppermint could be watered with CBMW at 50% (half CBMW half good quality water) without reduction of fresh herbage yields. However, CBMW at 75% and at 100% reduced fresh herbage yields of both crops and oil yields of peppermint. CBMW did not reduce spearmint oil yields. Technical Abstract: Coal bed methane (CBM) is extracted from underground coal seams, flooded with water. In order to reduce the pressure and release the methane, the trapped water needs to be pumped out. The resulting ‘waste water’ is known as coal-bed methane water (CBMW). Major concerns with the use of CBMW are the high concentrations of S, Na, and salts. The objective of this study was to evaluate the effect of various levels of CBMW on the growth, essential oil content, composition and antioxidant activity of spearmint and peppermint. The treatments were: 0% CBMW (control, tap water only), 25% (25% CBMW plus 75% tap water), 50% CBMW (half CBMW and half tap water), 75% CBMW (75% CBMW plus 25% tap water), and 100% CBMW. CBMW treatments did not affect the antioxidant capacity of spearmint or peppermint essential oil, and their major oil constituents, carvone or menthol, respectively. These traits seem to be more conservative. CBMW at 100% increased total phenols and total flavonoids in peppermint, but not in spearmint. CBMW at 25% increased fresh herbage yields of spearmint, but not in peppermint. Native spearmint and peppermint could be watered with CBMW at 50% (half CBMW half good quality water) without reduction of fresh herbage yields. However, CBMW at 75% and at 100% reduced fresh herbage yields of both crops and oil yields of peppermint. CBMW did not reduce spearmint oil yields. |