Mountains are essential sources of freshwater for our world, but their role in global water resources could well be significantly altered by climate change. How well do we understand these potential changes today, and what are implications for water resources management, climate change adaptation, and evolving water policy? To answer above questions, we have examined 11 case study regions with the goal of providing a global overview, identifying research gaps and formulating recommendations for research, management and policy. <br><br> After setting the scene regarding water stress, water management capacity and scientific capacity in our case study regions, we examine the state of knowledge in water resources from a highland-lowland viewpoint, focusing on mountain areas on the one hand and the adjacent lowland areas on the other hand. Based on this review, research priorities are identified, including precipitation, snow water equivalent, soil parameters, evapotranspiration and sublimation, groundwater as well as enhanced warming and feedback mechanisms. In addition, the importance of environmental monitoring at high altitudes is highlighted. We then make recommendations how advancements in the management of mountain water resources under climate change could be achieved in the fields of research, water resources management and policy as well as through better interaction between these fields. <br><br> We conclude that effective management of mountain water resources urgently requires more detailed regional studies and more reliable scenario projections, and that research on mountain water resources must become more integrative by linking relevant disciplines. In addition, the knowledge exchange between managers and researchers must be improved and oriented towards long-term continuous interaction

[1] The nature of the snowpack has the potential to strongly influence the patterns of alpine plant productivity and composition by governing soil moisture levels, growing season duration and the thermal regime of alpine soils. This study evaluates these relationships by modeling the interrelationships of snow depth, snow water equivalent (SWE), snow disappearance rate, soil moisture, attributes of the alpine plant community and selected terrain factors using decision-tree techniques at Niwot Ridge, Colorado Front Range. The modeling results showed a strong correlation (r 2 > 0.9, P < 0.001) between the snow disappearance rate and SWE and terrain factors that control the degree of shelter and exposure of a given local and elevation. The model was sufficiently robust to predict the spatial distribution of the snowpack for 12 years that exhibited average snow fall (r 2 = 0.8, P < 0.001), but yielded lower correlation (r 2 = 0.2, P < 0.001) in drought years. Soil moisture was significantly correlated (r 2 = 0.7, P < 0.001) with snow-fall amounts and terrain factors; however, meltwater and summer rain offset the potential soil moisture deficit in windward sites. Annual plant biomass did not correlate well with snow attributes and soil moisture because the cascading impact of topography on snowpack and soil moisture was not well captured by measurements of aboveground biomass. In contrast, the species richness index was significantly correlated with snow depth and soil moisture (r 2 = 0.7, P < 0.001), thereby demonstrating the importance of snow on some attributes of the alpine plant community.Citation: Litaor, M. I., M. Williams, and T. R. Seastedt (2008), Topographic controls on snow distribution, soil moisture, and species diversity of herbaceous alpine vegetation, Niwot Ridge, Colorado,

Soil interstitial waters are an extremely important facet of many environmental studies. The biogeochemical cycles of important nutrients, metal migration across the landscape, and pollutant movement to groundwater are highly affected by the water flow characteristics in soils and sediments. The purpose of this review is to evaluate the various soil solution sampling techniques. There is no single device that will perfectly sample soil solution in all conditions encountered in the field; hence a critical literature review on the different soil solution samplers is given. The differences among the various soil solution samplers and their relative advantages and limitations are discussed. The problems involved in using these samplers are assessed and plausible solutions are presented. SOIL SOLUTION SAMPLING: LITERATURE REVIEW The importance of soil solutions in environmental studies was recognized long ago by Joffe [1933], who described the soil solution as the "blood circulation of the soil body." The chemical properties of soil solutions have been studied by soil scientists, hydrologists, geochemists, ecologists, engineers, and health safety specialists for years and for a variety of reasons. The chemistry of soil solutions provide important information regarding the spatial and temporal distribution of nutrients [Soilins et aI., 1980] and their mobility and availability to plants [SSSA, 1983]. Soil solutions also provide crucial data concerning acid-neutralizing capacity (ANC) of a soil system [David and Driscoll, 1984] and the magnitude and rate of movement of pollutants to groundwater [Fortescue, 1980]. Other studies have demonstrated that soil solutions are an extremely important facet of the chemical budget for a watershed [Soilins et al., 1980; Cronan and Aiken, 1985; Driscoll et al., !985]. The chemistry of soil solution can also be used as a sensitive medium for calibrating and validating theoretical models of solute transport [Van de Pol et al., 1977]. Soil solutions provide information about the kinetics of solidsolution interaction in situ [Murali and Aylmore, 1980]. Mcdo-•,ell and Wood [1984] used soil solution chemistry to asses the mechanism of podzolization and pedologica! control on dissolved organic carbon concentrations in stream water. Various methods and devices for collection of soil solution have been used extensively for almost .a century. Contradictory results are often encountered in the literature concerning the sampling of soil solutions. Many reports have reviewed different techniques or devices, but their extent has been limited and specific to an individual study. There is no modern comprehensive review of this subject. The intent of this report is to fill this gap. TERMINOLOGY Various terms have been used to describe the different methods of sampling soil solution; a few of these terms are porous tube device [Krone et al., 1951], tension lysimeter [Cole, 1958], ceramic points [Shimshi, 1966], tension-free lysimeter [Jordan, 1968], pan and deep pressure vacuum lysimeters [Parizek and...

Phosphorus loss from land can be a major factor affecting surface water quality. We studied P-release mechanisms in wetland soils that had been drained and cultivated for four decades and then re-flooded. We measured redox, pH and solution composition in two sites in the field and in four peat and calcareous soils incubated in biogeochemical microcosms. The redox and pH measurements during the 120 days of incubation and the resulting soil solution composition indicated that the main process leading to P release is reductive dissolution of ferric hydroxides on which P was adsorbed and in which P was occluded. The molar Fe:P ratio increased with period of reduction from below 1 in the first week of re-flooding to 15-60 after 120 days. This suggests an increased P-retention capacity upon reoxidation of the soil solution, whether within the soil profile or in the drainage canals. Prolonged flooding of the calcite-poor, gypsumrich peat soils increased the oversaturation of soil solutions with respect to hydroxyapatite and occasionally -Ca 3 (PO 4 ) 2 (c), indicating that in spite of the large Ca concentration, the rate of Ca-P precipitation was insufficient to maintain the saturation status of the Ca-P system. In the calcareous soils the Ca-P system effectively controlled the P activity in soil solution throughout the incubation period. In both cases the precipitation of Ca-P minerals could be an important P-retention mechanism.

The chemical and mineralogical properties of the soils in an alpine watershed, Front Range, CO, were studied to assess the sensitivity of the soil environment to acid deposition. Field and laboratory analyses indicated that properties of surface horizons were heavily influenced by eolian dust accumulation whereas the subsurface horizons were mainly derived from local bedrock. Surface and subsurface horizons differed in texture, bulk density, pH, CEC, exchangeable cations, and clay and silt mineralogy. A discriminant analysis based on these parameters proved useful for confirming lithologic differences between the surface (alpine loess) and subsurface horizons (bedrock residua). The alpine environment in the Front Range, which is naturally acidic and therefore very susceptible to acid deposition, has been affected by wind‐blown calcite that has raised the pH of surface horizons. Such natural liming presumably increases the ability of the alpine soils to buffer acid deposition.