RESUMO
Dengue is native to tropical areas. It has expanded into temperate and arid zones in Mexico. Due to climate change, it is urgent to study the behavior of this disease in northwestern Mexico. Incidence of dengue fever and monthly maximum and minimum temperature and rainfall were obtained for 1990-2013 for the State of Baja California Sur. The relation between monthly and seasonal climate data with dengue records was analyzed by Pearson's correlation. The analysis shows that the minimum temperature has increased and the climate factor significantly correlates with dengue. Temperature variations have decreased. In this state, incidence of dengue cases directly correlates with minimum monthly temperature. It is expected that, as minimum temperatures increase to the end of this century, it will likely lead to increasing incidence of dengue. Preventive actions are recommended.
RESUMO
Activities of fishermen in the Bay of La Paz, B. C. S. are focused to satisfy the local demand of fish and shellfish by using approximately 300 small outboard crafts equipped with gillnets. Sea lions in this Bay attack the fishes captured damaging both product and gear. We did experimental gillnet throws to determine the frequency and preferences of sea lions in fishing areas. 52 experimental gillnet throws with time averages of 2 hr were performed, rending an average of 30 kg of fish captured and less than 10% of damages to the net.. Traditional fishermen in this Bay usually left the net the whole night, (approximately 7.50 hr, obtaining an average of 50 kg of captured fish, but the damages to the nets is in average of 40%. The cost-benefit balance comparing our alternative fishing method, which includes the use of the gillnets during the afternoon, watching for sea lions and retiring the nets at their arrival, it is more sustainable and profitable than the traditional fishing method currently used by the local fishermen. This paper suggests how to minimize the harmful effects of the sea lions on the fishermen productivity and gear, maximizing the production and reducing the damage. Our alternative method is applicable to other regions where this harmful interaction is taking place. We conclude that the coexistence of sea lions-fisheries is feasible, by applying the simple measures that we propose.
Assuntos
Comportamento Animal , Pesqueiros/métodos , Peixes , Leões-Marinhos , Animais , Pesqueiros/economia , Pesqueiros/instrumentação , MéxicoRESUMO
We evaluated the content of arsenic in soils of an abandoned mining zone in the Cape Region, B.C.S. During June to August 1997, we were in the field sampling these soils. The concentration of arsenic was determined using the Chapman and Parket techniques. The results were statistically analyzed by ANOVA tests. Our results indicate that all the soils sampled in the region exceed the environmental limit (2 mg/K) established by Galvan and Corey (1987). According to the data found the more probable cause of this soil arsenic contamination is the rainy runoff.