Sedimentary plains with extremely flat topography, such as the Pampas in Argentina, often display flooding–drought cycles. Changes in water table depth and surface water coverage affect natural and cultivated vegetation, wildlife, and people. Here, we describe groundwater dynamics and water-body expansion in a 10-year flooding cycle in the valuable agricultural lands of Western Pampas. We analy...

gypsiferous soils occur in xeric, ustic, and aridic moisture regimes. environmental conditions affect the mode of gypsum formation. gypsiferous soils in fars province, southern iran, are found in piedmont plains, flood plains, and alluvial plains. the objective of this work was to investigate the micromorphology of gypsum crystals formed under different soil moisture regimes. the results indica...

In much of the northern Great Plains, saline and hypersaline lacustrine brines are the only surface waters present. As a group, the lakes of this region are unique: there is no other area in the world that can match the concentration and diversity of saline lake environments exhibited in the prairie region of Canada and northern United States. The immense number of individual salt lakes and sal...

Ground-water availability from the High Plains aquifer in Southwest Kansas Ground-water Management District 3 (GMD 3) is declining as it is elsewhere in the western part of the state (Figure 1). Water-use density, defined as the annual amount of water pumped from the aquifer per unit of land area, is high over much of the District and greatly exceeds annual recharge (McMahon et al., 2003). Subs...

Sapindus is a genus of shrubs and small trees in the Sapindaceae family 1, . The genus comprises three major species: The American spices, Sapindus saponaria and two Asian species, Sapindus mukorossi and Sapindus trifoliatus. The American species Sapindus saponaria is popularly known as western soapberry, cherrioni, jaboncillo, sabao-de-macaco, saboeiro, saboneteiro, fruta de sabao, sabao-de-so...

This paper describes the hitherto unknown larva of Apatania helvetica Schmid 1954. Sequence data from the mitochondrial cytochrome c oxidase region were used to associate adult females and larvae. Genetic data confirmed the autochthonous status of this taxon within the parthenogenetic Apatania muliebris Complex ('sous groupe') sensu Schmid 1954. Information on the morphology of the larva is giv...

Drainage systems of the Great Plains and western Gulf Slope underwent substantial changes through diversions and stream captures during the Pleistocene, either as the result of the glacial advances or through independent geologic processes. The distributions of a variety of fishes that range across west-central North America, such as the plains killifish (Fundulus zebrinus), are thought to be t...

[1] Net primary productivity (NPP) in North America was computed for the years 1982–1998 using the Carnegie-Ames-Stanford approach (CASA) carbon cycle model. CASA was driven by a new, corrected satellite record of the normalized difference vegetation index at 8-km spatial resolution. Regional trends in the 17-year NPP record varied substantially across the continent. Croplands and grasslands of...