Analysis Of The Soil Sustaining Salt Grass (Distichlis Spicata (L.) Greene) Wild Populations In A Semiarid Coastal Zone Of Mexico

Wild populations of salt grass (Distichlis spicata (L.) Greene) are found in salt and brackish coastal marshes of Canada, USA and México. Salt grass is important for the northwestern states of Mexico, because it grows in dry and saline habitats, and because its foliage is mainly produced during periods when other grasses are not available for livestock and wild life. This study was conducted to determine the soil condition of the areas where this plant is dominant. Twenty-one soil variables were analyzed by means of multivariate analysis. Six soil samples from estuary and three soil samples from sandy beach were collected from five coastal sites of Baja California Sur, Mexico. We used the Principal Components Analysis (PCA) procedure to determine: 1) The best fitting lineal functions, 2) the variables with the highest loading, and 3) an approach to soil characterization. Two linear functions, explained 87% of the total variance, which indicated that native salt grass populations are well adapted to hyper-saline soil condition, and also to saline beach dry soil. Electrical conductivity (EC), permanent wilting point (PWP), and soil saturation (SAT), were the variables with the highest loading values as they gave the strongest numerical consistency to the linear functions. The first function was defined as a hyper-saline condition associated to the saturation point of the soil. The second was defined as a dry soil function. After applying the obtained functions to the collected data represented on axis, the existence of three soil groups with different saline condition were detected: Hyper-saline soils from estuary with a humidity near to the permanent wilting point value, hyper-saline soils from estuary with a humidity close to the soil saturation point, and saline beach dry soil.