Anthropogenic landscape decreases mosquito biodiversity and drives malaria vector proliferation in the Amazon rainforest

percentages (< 25%) represent higher malaria risk in terms of human presence and a higher density of a competent vector species. Overall, the results of the analyses showed that PLAND is a predictor variable for Ny. dar- lingi dominance in endemic areas of the Brazilian Amazon. Abundance of the mosquito vec- tors decreases with increase in the percent forest cover. Despite we have not directly tested the source-sink dynamics, the relationship between vector abundance and forest cover can also receive a contribution from this ecological range, as described by various authors [51, 52, 95]. In a malaria landscape where Ny. darlingi is the dominant vector, the source habitats are those that export individuals of the species, whereas the sink habitats import individuals, thereby sustaining the population in the heterogeneous landscape. The forest edge represents the source, whereas inside and nearby human dwellings represent the sink habitat for Ny. darlingi, with recolonization from sources due to a continuous process of increasing forest edge length by forest clearing and habitat fragmentation for human occupation and changes in land use. The establishment of a new Ny. darlingi population in a sink habitat is facilitated by the high reproductive success of the species, and rapid population growth in the Amazonian landscape. In addition, high temperature increases the development rate of immature stages as demon- strated by Chu et al. [35]. Populations in sink areas tend to occupy low-quality habitats that do

not support them for long, whereas those in source areas, with high-quality habitat, persist lon- ger and contribute to the recolonization of other fragments through dispersal of a fraction of the individuals [96]. Ecological factors that maintain Ny. darlingi in the peridomestic habitat (S7A Fig in S1 File) and the forest fringe (S7B Fig in S1 File) were impacted by PLAND and ED variables. The rela- tionship between niche requirements and the patterns of landscape structure are supported by several studies of Ny. darlingi bionomics [21, 34, 97]. Therefore, considering the ecological determinants of the presence of Ny. darlingi, a low edge density can represents a source habitat because the availability of habitats for females to lay their eggs increases [34]. In contrast, a high edge density represents a sink habitat because the occurrence of habitat suitable for ovi- position decreases [88]. In the peridomestic habitat, this mechanism is reversed, with Ny. dar- lingi the most abundant species. Likely, the anthropophilic/opportunistic blood-feeding behavior of the species facilitates the occurrence of part of the population in close contact with humans and domestic animals in an anthropogenic landscape. In Iquitos, Peruvian Amazon, the Ny. darlingi population is opportunistic, with a high proportion of the population feeding on humans (42.5%), and an unexpectedly 25.1% of individuals blood-feeding on avian hosts [98]. Similar results were found for Ny. darlingi collected in eastern Amazonian Brazil [99],

where the availability of host species influences the blood feeding preference of the mosquito. In conclusion, our study demonstrated that changes in Brazilian Amazon landscapes decrease overall Culicidae diversity and allow Ny. darlingi to become dominant if forest cover percentage decreases and edge density is low. Fragmented forest habitats inhabited by vulnera- ble people in precarious houses are the sources of this species, whereas continuous forested habitats or completely deforested habitats are sinks. The PLAND showed an empirical influ- ence on blood-feeding activities and ED on oviposition behavior both lead to high Ny. darlingi abundance in the peridomestic habitat. Considering the key role of Ny. darlingi in malaria transmission cycle, our finding is highly relevant for understating heterogeneities in the dynamics of malaria epidemiology. Supporting information S1 File. (PDF) PLOS ONE Anthropogenic landscape and mosquito biodiversity drives malaria vector proliferation PLOS ONE | https://doi.org/10.1371/journal.pone.0245087 January 14, 2021 19 / 25