[1] Vegetation, particularly its dynamics, is the often-ignored linchpin of the land-surface hydrology. This work emphasizes the coupled nature of vegetation-water-energy dynamics by considering linkages at timescales that vary from hourly to interannual. A series of two papers is presented. A dynamic ecohydrological model [tRIBS + VEGGIE] is described in this paper. It reproduces essential wat...

The International Arid Lands Consortium (IALC) was established in 1990 to promote research, education, and training activities related to the development, management, and reclamation of arid and semiarid lands in the Southwestern United States, the Middle East, and elsewhere in the world. The Consortium supports the ecological sustainability and environmentally sound stewardship of these lands ...

We used the natural abundance of stable isotopic ratios of hydrogen and oxygen in soil (0.05-3 m depth), plant xylem and precipitation to determine the seasonal changes in sources of soil water uptake by two native encroaching woody species (Pinus ponderosa P. & C. Lawson, Juniperus virginiana L.), and two C(4) grasses (Schizachyrium scoparium (Michx.) Nash, Panicum virgatum L.), in the semiari...

soil organic carbon is a key factor in productivity and quality of soil and environment particularly in semi arid regions. in this article, the role of farm soil organic matter management in soil and in land is discussed. the variability of soil organic carbon in drylands is mainly controlled by tillage and crop residue management. results of this study indicated that usage of correct tillage m...

Emissions of N2O from soils of the Southwestern US are thought to result from the activity of anaerobic denitrifying bacteria, but the seasonal dryness and sandy texture of these soils are more conducive to the activities of aerobic microbes. Here, we present incubations of semiarid soils with added compounds known to stimulate the N-cycling processes ammonification (proteins, oligopeptides, an...

A method to simultaneously determine calcite surface area and content in soils has been developed. The proposed procedure is based on rates of CO2 production upon reaction of soil with buffered acid solutions under controlled conditions. A pressure transducer connected to a chart recorder allows determination of soil calcite dissolution rate, which is directly proportional to calcite surface ar...

Nitrogen (N) deposition has been steadily increasing for decades, with consequences for soil respiration. However, we have a limited understanding of how soil respiration responds to N availability. Here, we investigated the soil respiration responses to low and high levels of N addition (0.4 mol N m(-2) yr(-1) vs 1.6 mol N m(-2) yr(-1)) over a two-year period in a semiarid Leymus chinensis gra...

Wildfires affecting forest ecosystems and post-fire silvicultural treatments may cause considerable changes in soil properties. The capacity of different microbial groups to recolonise soil after disturbances is crucial for proper soil functioning. The aim of this work was to investigate some microbial soil properties and enzyme activities in semiarid and dry Aleppo pine (Pinus halepensis M.) f...

Objective: Soil salinity is one of the major worldwide environmental constraints affecting agricultural production in arid and semiarid regions. Lack of proper management of water and soil resources lead to increase soil salinity and reduce soil fertility. On the other hand, it seems simple and cheap method of measuring soil salinity is necessary. The aim of this study was to determine the rela...