Two Microenvironments at the Soil Surface of Saline Wetlands in Monegros, Spain

Autor: Carmen Castañeda, Manuela Domínguez-Beisiegel, Juan Herrero
Rok vydání: 2013
Předmět:
Zdroj: Digital.CSIC. Repositorio Institucional del CSIC
instname
ISSN: 0361-5995
Popis: 23 Pags., 3 Tabls., 8 Figs. The definitive version is available at: https://www.soils.org/publications/sssaj
Non-trodden soils free of human and livestock pedestrian activity occur on the floors of hypersaline playa-lakes in the Monegros’ inland wetlands in Spain. A soil surface vesicular crust (herein designed as A1v horizon) organized in decimetric polygonal plates is the main observable feature of these rare soils inhabited by the perennial halophyte shrub Arthrocnemum macrostachyum (Moric.) Moris (A.m.). The vesicular organization of the A1v, together with its discontinuity with the soil underneath, suggests the existence of two contrasting soil microenvironments. Thirty-three sites of seven wetlands inhabited by A.m. were sampled: the A horizon from 0 to 15 cm, that is, including A1v; and separately the A1v and the underneath A2 horizon up to 15-cm depth. Measurements included Munsell color, moisture, and salinity at different soil/water ratios, during both the dry and wet seasons along with determinations of gypsum content, calcium carbonate equivalent, and organic matter. Evidence of the mulching effect of A1v and its contrasting conditions against the underlying A2 is supported by the significant differences in 1:5 soil/water extracts electrical conductivity, with a July mean EC1:5 of 22.3 dS m−1 in A1v vs. 14.0 dS m−1 in A2, and by similar significant differences in all major ions, except Ca. In July, total dryness (0%) can be achieved by A1v whereas A2 retained some moisture (5% minimum). Significant moisture differences were found for A1v and A2 in December together with a homogenizing effect. These are significant traits to be considered both in halophyte germination and establishment studies, and in ecological and restoration plans.
The first author was granted by INIA (Spanish Government). The article is a result of the Spanish projects AGL2009-08931, 2012GALC036, and PI200840I246.
Databáze: OpenAIRE
Externí odkaz: