Relationship between land cover and Anophelinae species abundance, composition and diversity in NW Colombia

摘要

Anthropic activities, mainly deforestation, have produced rapid transformation of land cover types in the Uraba region at northwest Colombia. Land cover alterations impact the abundance and composition of the Anophelinae community, affecting malaria transmission dynamics. Therefore, this study used landscape metrics to evaluate the relationship of land cover types with Anophelinae species abundance, composition and diversity in the important malaria endemic Uraba region, in NW Colombia. Orthorectified aerial photographs were used to identify land cover types in four localities of the region. Landscape metrics were obtained and diversity indices were estimated for both, land covers and Anophelinae species collected. The impact of land cover type on the presence and abundance of Anophelinae species was evaluated using a canonical correspondence analysis. Diversity indices showed differences in the Anophelinae community and land covers. The variables with more influence in the Anophelinae community composition were locality, bare soil and the interaction between forest and bare soil covers. The most abundant and dominant species Nyssorhynchus nuneztovari (former Anopheles nuneztovari), related with impacted environments was associated with grass, shrub and bare soil land covers. In conclusion, land covers derived from anthropic activities favored the presence and abundance of the main malaria vectors; but, regardless of differences in landscape, unknown specific factors varying among localities lead to a unique configuration in each site that directly shaped anopheline community composition locally. This information is essential for the development of malaria risk maps and for the design of integrated vector control interventions that include the recognition of the landscape features favoring human-vector contact.