Resumen

SANCHEZ, Alberto et al. Geochemistry of sediments in areas affected and unaffected by dredge fishing by the Sonora-Sinaloa coast, Gulf of California. Bol. Soc. Geol. Mex [online]. 2009, vol.61, n.1, pp.25-30. ISSN 1405-3322.

The geochemical and sedimentological studies conducted to assess the impact of bottom trawling in Mexico, are virtually absent. In this research are contrasted trawling and not-trawling sites of shrimp fishing in the coast of Sinaloa-Sonora. The analysis of grain-size indicated statistically significant differences between trawling and not-trawling sites. Unexpectedly, the geochemical variables (calcium carbonate, carbon and organic nitrogen, the ratio C/N and the stables isotopes of carbon and nitrogen) in both areas (pristine and impacted) were not statistically different. Our data suggest that the transport of materials and energy regulated, in both areas, biogeochemical processes that determine the ranges of these variables and that make them not statistically different. In fact, the ecosystem under the effect of bottom trawling in the coast of Sinaloa-Sonora is able to absorb this impact.

Palabras llave : Bottom trawling; Geochemistry; C/N ratio; stables isotopes of C and N; Gulf of California.