Mapping "old" vs. "young" pi?on-juniper stands with a predictive topo-climatic model

Pi?on pine and juniper woodlands in the southwestern United States are often represented as an expanding and even invasive vegetation type, a legacy of historic grazing, and culpable in the degradation of western rangelands. A long-standing emphasis on forage production, in combination with recent hazard fuel concerns, has prompted a new era of woodland management with stated restoration objectives. Yet the extent and dynamics of pi?on-juniper communities that predate intensive Euro-American settlement activities are poorly known or understood, while the intrinsic ecological, aesthetic, and economic values of old-growth woodlands are often overlooked. Historical changes in pi?on-juniper stands include two related, but poorly differentiated processes: recent tree expansion into grass- or shrub-dominated (i.e., non-woodland) vegetation and thickening or infilling of savanna or mosaic woodlands predating settlement. Our work addresses the expansion pattern, modeling the occurrence of "older" savanna and woodland stands extant prior to 1850 in contrast to "younger" pi?on-juniper growth of more recent, postsettlement origin. We present criteria in the form of a diagnostic key for distinguishing "older," pre-Euro-American settlement pi?on-juniper from "younger" (post-1850) stands and report results of predictive modeling and mapping efforts within a north-central New Mexico study area. Selected models suggest a primary role for soil moisture in the current distribution of "old" vs. "young" pi?on-juniper stands. Presettlement era woodlands are shown to occupy a discrete ecological space, defined by the interaction of effective (seasonal) moisture with landform setting and fine-scale (soil/water) depositional patterns. "Older" stands are generally found at higher elevations or on skeletal soils in upland settings, while "younger" stands (often dominated by one-seed juniper, Juniperus monosperma) are most common at lower elevations or in productive, depositional settings. Modeling at broad regional scales can enhance our general understanding of pi?on-juniper ecology, while predictive mapping of local areas has potential to provide products useful for land management. Areas of the southwestern United States with strong monsoonal (summer moisture) patterns appear to have been the most susceptible to historical woodland expansion, but even here the great majority of extant pi?on-juniper has presettlement origins (although widely thickened and infilled historically), and old-growth structure is not uncommon in appropriate upland settings.     

Applying models of employee identity management across cultures: Christianity in the USA and South Korea

Identity management refers to the decisions individuals make about how they present their social identities to others. We examined cross‐cultural differences in distancing and affirming identity management strategies of Christian‐identified employees utilizing samples from the USA and South Korea. Religious centrality, risks of disclosure, pressure to assimilate to organizational norms, and nation were key antecedents of chosen identity management strategies. Risks of disclosure and pressure to assimilate related to more distancing and less affirming strategies when religious centrality was low, but nation served as a boundary condition for the moderating effects of religious centrality. Distancing strategies related to negative outcomes regardless of religious centrality, but affirming strategies only related to positive outcomes when religious centrality was low. We discuss how this work contributes to theoretical and practical understanding of identity management in the workplace and across cultures. Copyright © 2014 John Wiley & Sons, Ltd.     

Quantity and quality of runoff from a beef cattle feedlot in southern Alberta

Southern Alberta, which has a cold climate dominated by strong chinook winds, has the highest density of feedlot cattle in Canada. However, the quantity and quality of runoff from beef cattle (Bos taurus) feedlots in this unique region has not been investigated. Our objectives were to compare runoff quantity (1998-2002) with catch-basin design criteria; determine concentrations of selected inorganic chemical parameters (1998-2000) in runoff in relation to water quality guidelines and the potential implications of irrigating adjacent crop-land; and determine if total heterotrophs, total coliforms, and Escherichia coli (1998-2000) persisted in the catch-basin water and soil. Runoff (< 0.1 to 42.5 mm) for a 24-h duration that included maximum peak discharge was less than the recommended design criteria of 90 mm based on runoff from 24 h of rainfall with a 30-yr return period. We found that curve numbers between 52 and 96 (mode of 90) were required to match the USDA Natural Resources Conservation Service predicted runoff and actual runoff volumes. Total P posed the greatest threat to water quality guidelines, and K posed the greatest threat for exceeding crop fertilizer requirements if catch-basin effluent was used as irrigation water. Water in the catch basin had continually high populations of E. coli throughout the study, with values ranging between log10 2 and log10 8 100 mL(-1). In contrast, soil in the catch basin generally had low populations of E. coli that were < log10 2 g(-1) wet wt., but at times higher populations between log10 2 and log10 6 g(-1) wet wt. were also found.     

Preliminary investigation of air bubbling and dietary sulfur reduction to mitigate hydrogen sulfide and odor from swine waste

When livestock manure slurry is agitated, the sudden release of hydrogen sulfide (H(2)S) can raise concentrations to dangerous levels. Low-level air bubbling and dietary S reduction were evaluated as methods for reducing peak H(2)S emissions from swine (Sus scrofa) manure slurry samples. In a first experiment, 15-L slurry samples were stored in bench-scale digesters and continuously bubbled with air at 0 (control), 5, or 10 mL min(-1) for 28 d. The 5-L headspace of each digester was also continuously ventilated at 40 mL min(-1) and the mean H(2)S concentration in the outlet air was <10 microL L(-1). On Day 28, the slurry was agitated suddenly. The peak H(2)S concentration exceeded instrument range (>120 microL L(-1)) from the control treatment, and was 47 and 3.4 microL L(-1) for the 5 and 10 mL min(-1) treatments, respectively. In a second experiment, individually penned barrows were fed rations with dietary S concentrations of 0.34, 0.24, and 0.15% (w/w). Slurry derived from each diet was bubbled with air in bench-scale digesters, as before, at 10 mL min(-1) for 12 d and the mean H(2)S concentration in the digester outlet air was 11 microL L(-1). On Day 12, the slurry was agitated but the H(2)S emissions did not change significantly. Both low-level bubbling of air through slurry and dietary S reduction appear to be viable methods for reducing peak H(2)S emissions from swine manure slurry at a bench scale, but these approaches must be validated at larger scales.     

Planning for change and sustainability in water development in Lao PDR and the Mekong River basin

With its recent opening to the global market economy, the natural resources of the Lao People's Democratic Republic (Lao PDR, referred to in this paper as Laos) – especially its water resources–have attracted external interest and investment. The overall level of water development is low. While even modest development would help Laos meet some of its urgent needs, past experience in Southeast Asia and other tropical regions suggests that fast-paced water development may damage the natural resource base. This article examines some efforts in water development from Southeast Asia and other regions and their relevance to water policy formulation in Laos. Future social and environmental changes in Laos are inevitable, but the nature and direction of these changes are uncertain. It thus makes sense to design policies that are flexible and can be adjusted to, and even take advantage of, a changing social and environmental context. Smaller-scale, deliberately-paced projects which merge local knowledge and external expertise fulfil the requirements of flexibility and adjustability, and are also appropriate for other important reasons: they do not require massive inputs of funding, and they do not initiate large-scale environmental and socio-economic changes. Current knowledge of the complex ecological and social systems in Laos is only sketchy. A slower-paced development will allow developers the necessary time to learn more about these important aspects.     

CLIMATE SCIENCE AND DROUGHT PLANNING: THE ARIZONA EXPERIENCE1

ABSTRACT: In response to recent severe drought conditions throughout the state, Arizona recently developed its first drought plan. The Governor's Drought Task Force focused on limiting the economic and social impacts of future droughts through enhanced adaptation and mitigation efforts. The plan was designed to maximize the use of new, scientific breakthroughs in climate monitoring and prediction and in vulnerability assessment. The long term objective of the monitoring system is to allow for evaluation of conditions in multiple sectors and at multiple scales. Stakeholder engagement and decision support are key objectives in reducing Arizona's vulnerability in light of the potential for severe, sustained drought. The drivers of drought conditions in Arizona include the El Nino‐Southern Oscillation, the Pacific Decadal Oscillation, and the Atlantic Multidecadal Oscillation.     

Towards resolving the phosphorus chaos created by food systems

Ambio - The chaotic distribution and dispersal of phosphorus (P) used in food systems (defined here as disorderly disruptions to the P cycle) is harming our environment beyond acceptable limits. An...