[1] Regular vegetation patterns in semiarid ecosystems are believed to arise from the interplay between long-range competition and facilitation processes acting at smaller distances. We show that, under rather general conditions, longrange competition alone may be enough to shape these patterns. To this end we propose a simple, general model for the dynamics of vegetation, which includes only l...

Anthropogenic N deposition poses a threat to European Mediterranean ecosystems. We combined data from an extant N deposition gradient (4.3-7.3 kg N ha⁻¹ yr⁻¹) from semiarid areas of Spain and a field experiment in central Spain to evaluate N deposition effects on soil fertility, function and cyanobacteria community. Soil organic N did not increase along the extant gradient. Nitrogen fixation de...

[1] Despite considerable research, large uncertainties exist in the various area-scales budgets of CH4 flux between soils and the atmosphere. We postulated that small wetlands greatly contribute to the CH4 budget in semiarid regions, where wetland contributions are often assumed to be insignificant. To test this hypothesis, small riparian mires of the Xilin River basin in Inner Mongolia were se...

Win ISAREG is a model for performing soil water balance and estimating impacts of water stress on yields for crops, concentrating on the evaluation of irrigation scheduling. The soil water balance of different type of soil and crop were study in the typical semiarid Horqin Sandy land area in this paper. With the data from Agula experimental station and concentrate on site A3 with Artemisia and ...

A population of 216 specimens of Stenocereus eichlamii (Cactaceae, Subfamily Cereoideae) was surveyed for Triatoma ryckmani (vector of Chagas disease) in a one hectare plot of semiarid habitat in Guatemala. Out of 44 plants that had dead and dry sections, 24 plants had a total of 103 specimens of T. ryckmani. In comparison with other areas of Guatemala, T ryckmani is well established in the sem...

Groundwater recharge is essential to groundwater resources availability to economy and society development in semiarid areas. Chloride mass balance method to assess groundwater recharge have been review and was employed to quantify groundwater recharge in North Okanagan which is a semiarid mountainous terrain, southern interior British Columbian, Canada. Chloride concentration in precipitation ...

In this study, we investigated the feasibility of using the C-band European Remote Sensing Satellite (ERS-1) synthetic aperture radar (SAR) data to estimate surface soil roughness in a semiarid rangeland. Radar backscattering coefficients were extracted from a dry and a wet season SAR image and were compared with 47 in situ soil roughness measurements obtained in the rocky soils of the Walnut G...

Records of the gastropod Melanoides tuberculatus (Müller, 1774), family Thiaridae, in the Piranhas-Assu River basin in Rio Grande do Norte reveal the dispersal of this native Southeast Asian and East African species into aquatic environments of the Brazilian semiarid region, including artificial environments (reservoirs) and lotic systems. The eutrophic conditions of the local waterbodies appea...

Increased atmospheric nitrogen (N) deposition and altered precipitation regimes have profound impacts on ecosystem functioning in semiarid grasslands. The interactions between those two factors remain largely unknown. A field experiment with N and water additions was conducted in a semiarid grassland in northern China. We examined the responses of aboveground net primary production (ANPP) and p...

Substantial tracts of land in the southwestern and western U.S. are undergoing or will require ERA. Toxicity bioassays employed in baseline ERAs are, for the most part. representative of mesic systems, and highly standardized test species (e.g., lettuce, earthworm) are generally not relevant to arid system toxicity testing. Conversely, relevant test species are often poorly characterized with r...