ALBERT

Description: Using data from two palaeontological databases, MIOMAP and FAUNMAP (now linked as NEOMAP), we explore how late Quaternary species loss compared in large and small mammals by determining palaeospecies-area relationships (PSARs) at 19 temporal intervals ranging from c. 30 million to 500 years ago in 10 different biogeographical provinces in the USA. We found that mammalian diversity of both large and small mammals remained relatively stable from 30 million years ago up until both crashed near the Pleistocene–Holocene transition. The diversity crash had two components: the well-known megafaunal extinction that amounted to c. 21% of the pre-crash species, and collateral biodiversity loss due to biogeographical range reductions. Collateral loss resulted in large mammal diversity regionally falling an additional 6–31% above extinction loss, and small mammal diversity falling 16–51%, even though very few small mammals suffered extinction. These results imply that collateral losses due to biogeographical range adjustments may effectively double the regional diversity loss during an extinction event, substantially magnifying the ecological ramifications of the extinctions themselves. This is of interest in forecasting future ecological impacts of mammal extinctions, given that c. 8% of USA mammal species, and 22% of mammal species worldwide, are now considered ‘Threatened’ by the IUCN.

Description: The US Army has compelling needs for making hydrological forecasts. These range from tactical predictions of water levels and soil moisture, to strategic protection of both Army and civilian assets and environmental resources. This paper discusses the history of hydrological model development by the US Army Corps of Engineers (USACE) as influenced by changes in needs and technologies. It concludes with a description of the Gridded Surface/Subsurface Hydrologic Analysis (GSSHA™) model, a two-dimensional, structured-grid, physics-based hydrological, hydrodynamic, sediment and nutrient/contaminant transport model, developed over the past two decades, that is currently used by the USACE. The surface hydrology of the USA has been divided by the US Geological Survey into 21 major geographic domains that contain either the drainage area of a major river or the combined drainage areas of a series of rivers of similar character developed in one geographic province. Eighteen of the regions occupy the land area of the conterminous USA. Alaska, the Hawaiian Islands and Puerto Rico are separate domains. This approach provides a framework for the hydrological modelling discussed in this paper for sites within six of these regions. That the physics-based GSSHA modelling capability has so far been applied with success gives confidence in its more widespread application.