Investigating the Effects of Habitat and Matrix Quality on Neotropical Mammal Biodiversity in Human-Modified Landscapes of Brazil
Quach, Lilly
0000-0003-1833-0561
:
2022-11-18
Abstract
According to the Habitat Amount Hypothesis, the total amount of habitat in a landscape should be the main determinant for species richness, but how does the quality of the habitat and the surrounding landcovers (termed the “matrix”) affect this relationship? The effects of habitat amount, habitat quality, and matrix quality on medium-to-large Neotropical mammals are indeterminate due to conflicting results from prior studies. To better understand how Neotropical medium-large mammal species richness responds to a gradient of habitat and matrix quality, I conducted my study in agricultural landscapes with low amounts of habitat (20-56%) in the Brazilian Cerrado. My study used remote sensing products such as the Enhanced Vegetation Index, MapBiomas land-use and landcover maps, Global Ecosystem Dynamics Investigation derived forest canopy height, and stream maps as landscape variables to measure the quality of the habitat and matrix. To measure the mammal biodiversity, I placed a motion detection camera trap in a forest patch within 16 different landscapes (3.14 km2). I extrapolated the Chao 1 species richness for each landscape and fit the data to generalized linear models with a Poisson distribution. The results suggest stream presence and shorter forest canopy height in the habitat are significantly correlated with higher species richness. Overall, habitat quality was shown to affect the medium-to-large mammal species richness more than habitat amount. However, habitat amount may have indirect effects at low thresholds (<30%) and future work should further consider how extremely low habitat amounts interact with habitat and matrix quality to affect mammal biodiversity.