Spatial and temporal variation in density and diversity of flying aquatic and terrestrial insects

The flux of organisms across the land/water interface can have profound effects on riparian and riverine community structure. Here, we examined the seasonal flux of flying aquatic emergent and terrestrial insects across temporal and spatial scales, in four streams in the Daly river catchment, in the wet-dry tropics of the Northern Territory. Spatially, our study was conducted at four streams that differ in catchment size (range: 5 1320 km2) and at each site, along a gradientin distance (1, 6, 11 and 16 m) from the stream edge. Temporally, all four streams were sampled once during the wet season (Feb) and once during the dry season (May). We used four Malaise traps left for 24 hours to sample abundance and diversity of insects. Results to date show that at all streams diversity of insects is greater closer to the stream edge and that catchment size is positively correlated with insect abundance. Through a better understanding of the spatial and temporal variation in insect fluxes we gain insight into the important processes that are driving the observed pattern.