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1. Soil disturbance by animals affects the availability of water, nutrients, sediment and seeds, which are critical for the maintenance of functional ecosystems. We examined long-lived faunal structures across six vegetation communities in the northern Chihuahuan desert of New Mexico, USA, testing the proposition that disturbances in undesertified grassland differ in magnitude and effect from those in desertified grassland. 2. Vertebrate and invertebrate disturbances totalled 18.9 structures ha−1 across 18 sites. The most common were pits and mounds of American badgers (Taxidea taxus, 32%), nests of the ant Aphaenogaster cockerelli (18.8%) and mounds of kangaroo rats (Dipodomys spectabilis, 31%). 3. Desertification...
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A battery of questions was developed and applied to different stakeholders immersed in knowledge of the condition and the use of grazing of grasslands. One hundred people were surveyed amongst livestock producers (both from private ranches and from communal ejidos), and students and researchers at regional institutions involved in agricultural sciences in different states of Mexico: Coahuila, Durango, San Luis Potosí, and Jalisco. The objective of the survey was to determine aspects of stakeholders’ interpretation of the condition of grasslands in their region under conditions of extensive grazing, such as soil condition, harvest efficiency, vegetation condition, openness to community organizing of grazing, capacity...
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Grasslands comprise a small part of the Chihuahuan Desert but are vital to the biological diversity of the ecoregion. Characteristic grasses of the Chihuahuan Desert are tobosa (Pleuraphis mutica) and black grama (Bouteloua eriopoda) but other common species include alakali sacaton (Sporobolus airoides), big alkali sacaton (S. wrightii), mesa dropseed (S. flexuosus), blue grama (B. gracilis), sideoats grama (B. curtipendula ), hairy grama (B. hirsuta), slender grama (B. filiformis), chino grama (B. brevista), spruce top grama (B. chondrosioides), bush muhly (Muhlenbergia porteri), several three awns (Aristida spp.), and fluff grass (Dasyochloa pulchela) (Johnson 1974, Dinerstein et al. 2000). Many of the sites discussed...
Medium-sized kangaroo rats (Dipodomys spp. Gray) function as keystone species in the dynamics of desert bunchgrasses. We tested the hypothesis that kangaroo rat graminivory leads to reduced grass growth and inflorescence production, and that kangaroo rat grass consumption reflects their preferences for open microhabitats. We excluded kangaroo rats from grasses, and measured tiller loss, leaf and tiller growth and inflorescence production. We recorded the extent of tiller loss in grasses varying in tussock size or the extent of surrounding cover. Consumption of tillers by kangaroo rats was extensive, peaking in late summer. Grasses protected from kangaroo rat graminivory showed elevated leaf and tiller growth and...


map background search result map search result map Status and Distribution of Chihuahuan Desert Grasslands in the United States and Mexico Perceptions of the condition of semiarid grasslands under grazing regimes in Mexico/ Percepción de la condición del pastizal  bajo pastoreo, en México semiárido Status and Distribution of Chihuahuan Desert Grasslands in the United States and Mexico Perceptions of the condition of semiarid grasslands under grazing regimes in Mexico/ Percepción de la condición del pastizal  bajo pastoreo, en México semiárido