Pesticides and farmers' health: an analysis of variables related to management and property.

The objective is to verify the effects of pesticides on the health of farmers in the southern region of Brazil, as well as the possible symptoms and cases of intoxication. This study has a quantitative, descriptive and exploratory approach, carried out in 12 agricultural locations in the municipality of Serra Catarinense. This research was approved by the research ethics committee and was applied through a structured questionnaire to 79 farmers who grow grains in the conventional cultivation system. The pesticide most used by farmers was glyphosate, followed by acephate. Of the individuals, 21.5% reported that they had suffered poisoning by pesticides by the respiratory route (58.8%). In addition, 28% had three symptoms of intoxication, demonstrating possible probable cases of intoxication. And 41% of workers reported headaches as a predominant symptom in applications with the use of pesticides, followed by dizziness/vertigo (16%). Farmers who use PPE during the preparation of the pesticide spray are neither chronic diseases (p<0.003) nor psychological problems (p<0.000). All four individuals who had cancer, all also eat while applying pesticides (p<0.049). The exposure to pesticides causes changes in the organism of those exposed, using them more vulnerable to health problems.

Plant litter dynamics in the forest-stream interface: precipitation is a major control across tropical biomes.

Riparian plant litter is a major energy source for forested streams across the world and its decomposition has repercussions on nutrient cycling, food webs and ecosystem functioning. However, we know little about plant litter dynamics in tropical streams, even though the tropics occupy 40% of the Earth's land surface. Here we investigated spatial and temporal (along a year cycle) patterns of litter inputs and storage in multiple streams of three tropical biomes in Brazil (Atlantic forest, Amazon forest and Cerrado savanna), predicting major differences among biomes in relation to temperature and precipitation regimes. Precipitation explained most of litter inputs and storage, which were generally higher in more humid biomes (litterfall: 384, 422 and 308 g m-2 y-1, storage: 55, 113 and 38 g m-2, on average in Atlantic forest, Amazon and Cerrado, respectively). Temporal dynamics varied across biomes in relation to precipitation and temperature, with uniform litter inputs but seasonal storage in Atlantic forest streams, seasonal inputs in Amazon and Cerrado streams, and aseasonal storage in Amazon streams. Our findings suggest that litter dynamics vary greatly within the tropics, but point to the major role of precipitation, which contrasts with the main influence of temperature in temperate areas.