CHAPTER VIII
THE MARISMAS OF GUADALQUIVÍR
THE DELTA
FROM Seville to the Atlantic the great river Guadalquivír pursues its course through seventy miles of alluvial mud-flats entirely of its own construction. The whole of this viewless waste (in winter largely submerged) is technically termed the marisma; but its upper regions, slightly higher-lying, have proved amenable to a limited dominion of man, and nowadays comprise (besides some rich corn-lands) broad pasturages devoted to grazing, and which yield Toros bravos, that is, fighting-bulls of breeds celebrated throughout Spain, as providing the popular champions of the Plaza.
It is not of these developed regions that we treat, but of the Lower Delta, which still remains a wilderness, and must for centuries remain so—a vast area of semi-tidal saline ooze and marsh, extending over some forty or fifty miles in length, and spreading out laterally to untold leagues on either side of the river.
This Lower Delta, the marisma proper, while it varies here and there by a few inches in elevation, is practically a uniform dead-level of alluvial mud, only broken by vetas, or low grass-grown ridges seldom rising more than a foot or two above the flat, and which vary in extent from a few yards to hundreds of acres. The precise geological cause of these vetas we know not; but the calcareous matter of which they are composed—the debris of myriad disintegrated sea-shells, mostly bivalves—proves that the ocean at an earlier period held sway, till gradually driven backwards by the torrents of alluvial matter carried down by the river, and finally forced behind the vast sand-barrier now known as the Coto Doñana—the buffer called into being whilst age-long struggles raged between these two opposing forces. The fact is further evidenced by the salt crust which yearly forms on the surface of the lower marisma when the summer sun has evaporated its waters.
In summer the marisma is practically a sun-scorched mud-flat; in winter a shallow inland sea, with the vetas standing out like islands.
There are, as already stated, slight local variations in elevation. Naturally the lower-lying areas are the first to retain moisture so soon as the long torrid summer has passed away and autumn rains begin. Speedily these become shallow lagoons, termed lucios—similar, we imagine, to the jheels of India—and a welcome haven they afford to the advance-guard of immigrant wildfowl from the north.
Plant-life in the marismas is regulated by the relative saltness of the soil. In the deeper lucios no vegetation can subsist; but where the level rises, though but a few inches, and the ground is less saline, the hardy samphire (in Spanish, armajo) appears, covering with its small isolated bushes vast stretches of the lower marisma.
The armajo, which is formed of a congeries of fleshy twigs, leafless, and jointed more like the marine algae than a land-plant, belongs to three species as follows:—
| (1) Salicornea herbacea, marsh-samphire; in Spanish, Sapina. | |||
| (2) Arthraenimum fruticosum (3) Suaeda fruticosa | —in Spanish, Armajo. |