We tested the hypothesis that herbivores contribute to feedbacks maintaining arid ecosystems in a degraded state. We studied small mammal herbivory on a subshrub, broom snakeweed (Gutierrezia sarothrae), and perennial grasses at three sites: (1) ungrazed black grama (Bouteloua eriopoda) grassland; (2) grassland degraded by intense short-duration grazing; and (3) mesquite (Prosopis glandulosa) c...

The invasive taxa of Prosopis is rated the world’s top 100 unwanted species, and a lack of spatial data about the invasion dynamics has made the current control and monitoring methods unsuccessful. This study thus tests the use of in situ spectroscopy data with a newly-developed algorithm, guided regularized random forest (GRRF), to spectrally discriminate Prosopis from coexistent acacia specie...

—Encroachment of woody plants is widespread in semiarid grasslands of the southwestern United States. Wildlife responses to shrub removal techniques in the region are relatively unknown. In 2008 and 2009, we examined avian responses to prescribed burning of ungrazed shortgrass prairie within a study area (4811 ha) near Amarillo, Texas, that is heavily encroached by honey mesquite (Prosopis glan...

Abstract Aims Grassland-to-shrubland transition is a common form of land degradation in drylands worldwide. It often attributed to changes disturbance regimes, particularly overgrazing. A myriad direct and indirect effects (e.g., accelerated soil erosion) grazing may favor shrubs over grasses, but their relative importance unclear. We tested the hypothesis that topsoil “winnowing” by wind erosi...

Wild species related to crops are a source of genes for improving crop tolerance biotic and abiotic stresses. Vasconcellea quercifolia V. glandulosa wild relatives papaya (Carica papaya). They the southernmost-distributed members genus have traits temperature precipitation seasonality. Climate land-use changes, however, threatening their persistence. Our objectives were identify priority ex sit...

Introduction: Obesity and its associated complications, such as the metabolic syndrome, hypertension and cardiovascular disease, are escalating worldwide. In recognition of this, untested remedies advertised as anti-diabetic agents are flooding the market. Many of these products have limited efficacy, limited tolerability and significant side-effects. One remedy, claiming to have anti-diabetic ...

Walvoord et al. (1) reported a large nitrate pool located deep ( 1 m) beneath desert soils. Two aspects of this work were particularly surprising: the large pool size, estimated to be up to 10 kilograms of nitrogen per hectare, as nitrate (kg N ha); and the shape of the nitrate profiles, which resembled the conservative solute-accumulation profiles of Cl more than typical nutrient depletion pro...