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The effects of climate change on plants and ecosystems are mediated by plant hydraulic traits, including interspecific and intraspecific variability of trait phenotypes. Yet, integrative and realistic studies of hydraulic traits and climate change are rare. In a semiarid grassland, we assessed the response of several plant hydraulic traits to elevated CO2 (+200 ppm) and warming (+1.5 to 3°C; day to night). For leaves of five dominant species (three graminoids and two forbs), and in replicated plots exposed to 7 years of elevated CO2, warming, or ambient climate, we measured: stomatal density and size, xylem vessel size, turgor loss point, and water potential (pre‐dawn). Interspecific differences in hydraulic traits were larger than intraspecific shifts induced by elevated CO2 and/or warming. Effects of elevated CO2 were greater than effects of warming, and interactions between treatments were weak or not detected. The forbs showed little phenotypic plasticity. The graminoids had leaf water potentials and turgor loss points that were 10% to 50% less negative under elevated CO2; thus, climate change might cause these species to adjust their drought resistance strategy away from tolerance and toward avoidance. The C4 grass also reduced allocation of leaf area to stomata under elevated CO2, which helps explain observations of higher soil moisture. The shifts in hydraulic traits under elevated CO2 were not, however, simply due to higher soil moisture. Integration of our results with others' indicates that common species in this grassland are more likely to adjust stomatal aperture in response to near‐term climate change, rather than anatomical traits; this contrasts with apparent effects of changing CO2 on plant anatomy over evolutionary time. Future studies should assess how plant responses to drought may be constrained by the apparent shift from tolerance (via low turgor loss point) to avoidance (via stomatal regulation and/or access to deeper soil moisture). [ABSTRACT FROM AUTHOR]

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Microbes in snow and ice ecosystems in polar regions contribute substantially to C, N, and P cycling, but few studies have explored microbial activity in seasonal snow. The purpose of this study was to explore the relative importance of snow microbial processing of C, N, and P compounds in atmospheric deposition and litter and detect elemental limitations of snow microbes in Rocky Mountain conifer forests. Enzyme activity in snow was orders of magnitude greater than activity reported for lentic and lotic waters in similar environments. Proportions of C/P‐ and C/N‐acquiring enzymes suggest that snow samples were P limited, or C and P co‐limited, while lentic and lotic waters were more N limited. As such, microbes in seasonal snow may change the composition of nutrients and carbon, but these processes are vulnerable to changes in atmospheric deposition and snow extent and duration, which could affect nutrient processing across large areas. [ABSTRACT FROM AUTHOR]

Background: Postoperative nutrition delivery is essential to surgical recovery; unfortunately, postoperative dietary intake is often poor. Recent surgical guidelines recommend use of oral nutritional supplements (ONS) to improve nutrition delivery. Our aim was to examine prevalence of coded ONS use over time and coded malnutrition rates in postoperative patients.Methods: The Premier Healthcare Database (PHD) was queried for postoperative patients found to have charges for ONS between 2008-2014. ONS use identified via charge codes. Descriptive statistics utilized to examine prevalence of malnutrition and ONS utilization. Multilevel, multivariable logistic regression models were fit to examine factors associated with ONS use.Results: A total of 2,823,532 surgical encounters were identified in PHD in 172 hospitals utilizing ONS charge codes. ONS-receiving patients were 72% Caucasian, 65% Medicare patients with mean age of 66 ± 16.5 years. Compared with patients not receiving ONS, ONS patients had higher van Walraven severity scores (7.3 ± 7.8 vs 2.3 ± 5.6, P < .001) with greater comorbidities. Overall coded malnutrition prevalence was 4.3%. Coded malnutrition diagnosis increased from 4.4% to 5.2% during study period. Only 15% of malnourished patients received ONS. Individual hospital practice explained much of variation in early postoperative ONS use.Conclusion: In this large surgical population, inpatient ONS use is most common in older, Caucasian, Medicare patients with high comorbidity burden. Despite increased malnutrition during study period, observed ONS prescription rate did not increase. Our data indicate current ONS utilization in surgical patients, even coded with malnutrition, is limited and is a critical perioperative quality improvement opportunity. [ABSTRACT FROM AUTHOR]

Although much is known about surgical risk, little evidence exists regarding how best to proactively address preoperative risk factors to improve surgical outcomes. Preoperative malnutrition is a widely prevalent and modifiable risk factor in patients undergoing surgery. Malnutrition prior to surgery portends significantly higher postoperative mortality, morbidity, length of stay, readmission rates, and hospital costs. Unfortunately, perioperative malnutrition is poorly screened for and remains largely unrecognized and undertreated-a true "silent epidemic" in surgical care. To better address this silent epidemic of surgical nutrition risk, here we describe the rationalization, development, and implementation of a multidisciplinary, registered dietitian-driven, preoperative nutrition optimization clinic program designed to improve perioperative outcomes and reduce cost. Implementation of this novel Perioperative Enhancement Team (POET) Nutrition Clinic required a collaboration among many disciplines, as well as an identified need for multidimensional scheduling template development, data tracking systems, dashboard development, and integration of electronic health records. A structured malnutrition risk score (Perioperative Nutrition Screen score) was developed and is being validated. A structured malnutrition pathway was developed and is under study. Finally, the POET Nutrition Clinic has established a novel role for a perioperative registered dietitian as the integral point person to deliver perioperative nutrition care. We hope this structured model of perioperative nutrition assessment and optimization will allow for wide implementation and generalizability in other centers worldwide to improve recognition and treatment of perioperative nutrition risk. [ABSTRACT FROM AUTHOR]

Premise: The impact of elevated CO2 concentration ([CO2]) and climate warming on plant productivity in dryland ecosystems is influenced strongly by soil moisture availability. We predicted that the influence of warming on the stimulation of photosynthesis by elevated [CO2] in prairie plants would operate primarily through direct and indirect effects on soil water. Methods: We measured light‐saturated photosynthesis (Anet), stomatal conductance (gs), maximum Rubisco carboxylation rate (Vcmax), maximum electron transport capacity (Jmax) and related variables in four C3 plant species in the Prairie Heating and CO2 Enrichment (PHACE) experiment in southeastern Wyoming. Measurements were conducted over two growing seasons that differed in the amount of precipitation and soil moisture content. Results: Anet in the C3 subshrub Artemisia frigida and the C3 forb Sphaeralcea coccinea was stimulated by elevated [CO2] under ambient and warmed temperature treatments. Warming by itself reduced Anet in all species during the dry year, but stimulated photosynthesis in S. coccinea in the wet year. In contrast, Anet in the C3 grass Pascopyrum smithii was not stimulated by elevated [CO2] or warming under wet or dry conditions. Photosynthetic downregulation under elevated [CO2] in this species countered the potential stimulatory effect under improved water relations. Warming also reduced the magnitude of CO2‐induced down‐regulation in this grass, possibly by sustaining high levels of carbon utilization. Conclusions: Direct and indirect effects of elevated [CO2] and warming on soil water was an overriding factor influencing patterns of Anet in this semi‐arid temperate grassland, emphasizing the important role of water relations in driving grassland responses to global change. [ABSTRACT FROM AUTHOR]

Resprouting is an ancestral trait in angiosperms that confers resilience after perturbations. As climate change increases stress, resprouting vigor is declining in many forest regions, but the underlying mechanism is poorly understood. Resprouting in woody plants is thought to be primarily limited by the availability of non‐structural carbohydrate reserves (NSC), but hydraulic limitations could also be important. We conducted a multifactorial experiment with two levels of light (ambient, 2–3% of ambient) and three levels of water stress (0, 50 and 80 percent losses of hydraulic conductivity, PLC) on two Mediterranean oaks (Quercus ilex and Q. faginea) under a rain‐out shelter (n = 360). The proportion of resprouting individuals after canopy clipping declined markedly as PLC increased for both species. NSC concentrations affected the response of Q. ilex, the species with higher leaf construction costs, and its effect depended on the PLC. The growth of resprouting individuals was largely dependent on photosynthetic rates for both species, while stored NSC availability and hydraulic limitations played minor and non‐significant roles, respectively. Contrary to conventional wisdom, our results indicate that resprouting in oaks may be primarily driven by complex interactions between hydraulics and carbon sources, whereas stored NSC play a significant but secondary role. Here we show that root non‐structural carbohydrate reserves only play a minor role as drivers of basal resprouting in Mediterranean oaks. The probability of resprouting was mostly driven by the degree of antecedent hydraulic limitations and the growth of the resprouts depended largely on photosynthetic C uptake. [ABSTRACT FROM AUTHOR]

Isotopic exchange with atmospheric vapour can strongly influence the isotopic values of evaporating surface water bodies (e.g., lakes), influencing our understanding of hydrological processes across aquatic and terrestrial environments. Rather than measure the isotopic values of the atmosphere directly, it is much more common to estimate values by assuming equilibrium with local precipitation. This assumption may introduce large errors, thereby biasing hydrological inferences and understanding. The pattern and magnitude of this error has been quantified only in a few circumstances. We compared observations of vapour and precipitation isotope values over a four‐year record collected in a montane environment in the central Rocky Mountains of North America. We further investigated factors and conditions promoting disequilibrium. Scenario comparisons assessed the impact of theoretical and methodological elements on the accuracy of the equilibrium assumption. We found that the equilibrium assumption was not well supported by direct and continuous observations of vapour isotopes using tower‐based laser isotope spectroscopy, particularly during the summer months. Across all scenarios, errors associated with the equilibrium assumption were high, credibly ranging from 14 to 154 ‰ for δ2H and 1.5 to 16.3 ‰ for δ18O. Environmental covariates (e.g., vapour pressure deficit, air pressure) helped explain some of the apparent disequilibrium. Although the equilibrium assumption for estimating atmospheric vapour isotope values may not be applicable in a continental montane environment, our findings highlight opportunities for using direct vapour isotope measurements to better understand vapour sources, air mass mixing, and phase changes over complex mountainous terrain, which in turn may better constrain regional‐ to global‐scale hydrological process estimates, such as evapotranspiration rates and the water budgets of mountain lakes. [ABSTRACT FROM AUTHOR]

Sublimation is an important hydrological flux in cold, snow‐dominated ecosystems. In high‐elevation spruce‐fir forests of western North America, spruce beetle outbreaks have killed trees, reduced the canopy, and altered processes that control sublimation. We evaluated two hypotheses related to effects of disturbance on sublimation in this ecosystem: (1) the dominant source for sublimation is canopy intercepted snow and (2) the loss of canopy following a beetle disturbance leads to less total sublimation. To incorporate uncertainty hierarchically across multiple data sources and address phenomenological parsimony, Bayesian statistics were used to analyze 17 years (2000–2016) of winter eddy covariance flux data at the Glacier Lakes Ecosystem Experiments Sites AmeriFlux sites where a spruce beetle outbreak caused 75–85% basal area mortality. Our analysis revealed that resistances to sublimate snow from the canopy were an order of magnitude less than from the snowpack, and the maximum snow loading capacity in disturbed canopies was reduced to 34% of its pre‐outbreak value. Total sublimation has decreased since 2010, 2 years after the main outbreak, declining 24% (with a 95% credible interval, C.I., between 18% and 38%) during 2014–2016 due to a 32% decrease in canopy sublimation. Snowpack sublimation only increased 3% over this period. With less total sublimation, the forest retained 6.1% (4.5–12.3% C.I.) more snowpack mass or equivalently 4.4% (3.2–8.8 C.I.) of the annual precipitation. Considering tree growth and ecological succession are slow in spruce‐fir forests, this decrease in sublimation should persist as an increased snowpack for decades, with substantial impacts on catchment hydrologic processes and potentially streamflow. Key Points: Ecosystem sublimation decreased 24% following a spruce beetle outbreak in a subalpine forest in Wyoming, USAA Bayesian analysis identified the loss of canopy causing less snow interception as the driver of this changeThis allows the snowpack to retain 6% more mass, an increase that is hydrologically, ecologically, and socially meaningful in this region [ABSTRACT FROM AUTHOR]

Premise of the Study: Giant cacti species possess long cylindrical stems that store massive amounts of water and other resources to draw on for photosynthesis, growth, and reproduction during hot and dry conditions. Across all giant cacti taxa, stem photosynthetic surface area to volume ratio (S:V) varies by several fold. This broad morphological diversity leads to the hypothesis that giant cacti function along a predictable resource use continuum from a "safe" strategy reflected in low S:V, low relative growth rates (RGR), and low net assimilation rates (Anet) to a high‐risk strategy that is reflected in high S:V, RGR, and Anet. Methods: To test this hypothesis, whole‐plant gas exchange, chlorophyll fluorescence, and whole‐spine‐tissue carbon isotope ratios (δ13C) were measured in four giant cacti species varying in stem morphology and RGR. Measurements were conducted on five well‐watered, potted plants per species. Key Results: Under conditions of mild diel temperatures and low atmospheric vapor pressure deficit, Anet, transpiration (E), and stomatal conductance (Gs) were significantly higher, and water‐use efficiency (Anet : Gs) was lower in fast‐growing, multi‐stemmed species compared to the slower growing, single‐stemmed species. However, under warmer, less optimal conditions, gas exchange converged between stem types, and neither δ13C nor chlorophyll fluorescence varied among species. Conclusions: The results add to a growing body of evidence that succulent‐stemmed plants function along a similar economic spectrum as leaf‐bearing plants such that functional traits including stem RGR, longevity, morphology, and gas exchange are correlated across species with varying life‐history strategies. [ABSTRACT FROM AUTHOR]

Aim: Within C3 plants, photosynthesis is a balance between CO2 supply from the atmosphere via stomata and demand by enzymes within chloroplasts. This process is dynamic and a complex but crucial aspect of photosynthesis. We sought to understand the spatial pattern in CO2 supply–demand balance on a global scale, via analysis of stable isotopes of carbon within leaves (Δ13C), which provide an integrative record of CO2 drawdown during photosynthesis. Location: Global Time period: 1951–2011. Major taxa studied: Vascular plants. Methods: We assembled a database of leaf carbon isotope ratios containing 3,979 species–site combinations from across the globe, including 3,645 for C3 species. We examined a wide array of potential climate and soil drivers of variation in Δ13C. Results: The strongest drivers of carbon isotope discrimination at the global scale included atmospheric pressure, potential evapotranspiration and soil pH, which explained 44% of the variation in Δ13C. Addition of eight more climate and soil variables (each explaining small but highly significant amounts of variation) increased the explained variation to 60%. On top of this, the largest plant trait effect was leaf nitrogen per area, which explained 11% of Δ13C variation. Main conclusions: By considering variation in Δ13C at a considerably larger scale than previously, we were able to identify and quantify key drivers in CO2 supply–demand balance previously unacknowledged. Of special note is the key role of soil properties, with greater discrimination on low‐pH and high‐silt soils. Unlike other plant traits, which show typically wide variation within sets of coexisting species, the global pattern in carbon stable isotope ratios is much more conservative; there is relatively narrow variation in time‐integrated CO2 concentrations at the site of carboxylation among plants in a given soil and climate. [ABSTRACT FROM AUTHOR]

Abstract: Temporal variation in soil nitrogen (N) availability affects growth of grassland communities that differ in their use and reuse of N. In a 7‐year‐long climate change experiment in a semi‐arid grassland, the temporal stability of plant biomass production varied with plant N turnover (reliance on externally acquired N relative to internally recycled N). Species with high N turnover were less stable in time compared to species with low N turnover. In contrast, N turnover at the community level was positively associated with asynchrony in biomass production, which in turn increased community temporal stability. Elevated CO2 and summer irrigation, but not warming, enhanced community N turnover and stability, possibly because treatments promoted greater abundance of species with high N turnover. Our study highlights the importance of plant N turnover for determining the temporal stability of individual species and plant communities affected by climate change. [ABSTRACT FROM AUTHOR]

Determining whether the terrestrial biosphere will be a source or sink of carbon (C) under a future climate of elevated CO2 ( eCO2) and warming requires accurate quantification of gross primary production ( GPP), the largest flux of C in the global C cycle. We evaluated 6 years (2007-2012) of flux-derived GPP data from the Prairie Heating and CO2 Enrichment ( PHACE) experiment, situated in a grassland in Wyoming, USA. The GPP data were used to calibrate a light response model whose basic formulation has been successfully used in a variety of ecosystems. The model was extended by modeling maximum photosynthetic rate ( Amax) and light-use efficiency ( Q) as functions of soil water, air temperature, vapor pressure deficit, vegetation greenness, and nitrogen at current and antecedent (past) timescales. The model fits the observed GPP well ( R2 = 0.79), which was confirmed by other model performance checks that compared different variants of the model (e.g. with and without antecedent effects). Stimulation of cumulative 6-year GPP by warming (29%, P = 0.02) and eCO2 (26%, P = 0.07) was primarily driven by enhanced C uptake during spring (129%, P = 0.001) and fall (124%, P = 0.001), respectively, which was consistent across years. Antecedent air temperature (Tairant) and vapor pressure deficit ( VPDant) effects on Amax (over the past 3-4 days and 1-3 days, respectively) were the most significant predictors of temporal variability in GPP among most treatments. The importance of VPDant suggests that atmospheric drought is important for predicting GPP under current and future climate; we highlight the need for experimental studies to identify the mechanisms underlying such antecedent effects. Finally, posterior estimates of cumulative GPP under control and eCO2 treatments were tested as a benchmark against 12 terrestrial biosphere models ( TBMs). The narrow uncertainties of these data-driven GPP estimates suggest that they could be useful semi-independent data streams for validating TBMs. [ABSTRACT FROM AUTHOR]

Human impacts on biogeochemical cycles are evident around the world, from changes to forest structure and function due to atmospheric deposition, to eutrophication of surface waters from agricultural effluent, and increasing concentrations of carbon dioxide (CO2) in the atmosphere. The National Ecological Observatory Network (NEON) will contribute to understanding human effects on biogeochemical cycles from local to continental scales. The broad NEON biogeochemistry measurement design focuses on measuring atmospheric deposition of reactive mineral compounds and CO2 fluxes, ecosystem carbon (C) and nutrient stocks, and surface water chemistry across 20 eco‐climatic domains within the United States for 30 yr. Herein, we present the rationale and plan for the ground‐based measurements of C and nutrients in soils and plants based on overarching or “high‐level” requirements agreed upon by the National Science Foundation and NEON. The resulting design incorporates early recommendations by expert review teams, as well as recent input from the larger natural sciences community that went into the formation and interpretation of the requirements, respectively. NEON's efforts will focus on a suite of data streams that will enable end‐users to study and predict changes to biogeochemical cycling and transfers within and across air, land, and water systems at regional to continental scales. At each NEON site, there will be an initial, one‐time effort to survey soil properties to 1 m (including soil texture, bulk density, pH, baseline chemistry) and vegetation community structure and diversity. A sampling program will follow, focused on capturing long‐term trends in soil C, nitrogen (N), and sulfur stocks, isotopic composition (of C and N), soil N transformation rates, phosphorus pools, and plant tissue chemistry and isotopic composition (of C and N). To this end, NEON will conduct extensive measurements of soils and plants within stratified random plots distributed across each site. The resulting data will be a new resource for members of the scientific community interested in addressing questions about long‐term changes in continental‐scale biogeochemical cycles, and is predicted to inspire further process‐based research. [ABSTRACT FROM AUTHOR]

Vegetation greenness, detected using digital photography, is useful for monitoring phenology of plant growth, carbon uptake and water loss at the ecosystem level. Assessing ecosystem phenology by greenness is especially useful in spatially extensive, water-limited ecosystems such as the grasslands of the western United States, where productivity is moisture dependent and may become increasingly vulnerable to future climate change., We used repeat photography and a novel means of quantifying greenness in digital photographs to assess how the individual and combined effects of warming and elevated CO2 impact ecosystem phenology (greenness and plant cover) in a semi-arid grassland over an 8-year period., Climate variability within and among years was the proximate driver of ecosystem phenology. Individual and combined effects of warming and elevated CO2 were significant at times, but mediated by variation in both intra- and interannual precipitation. Specifically, warming generally enhanced plant cover and greenness early in the growing season but often had a negative effect during the middle of the summer, offsetting the early season positive effects. The individual effects of elevated CO2 on plant cover and greenness were generally neutral., Opposing seasonal variations in the effects of warming and less so elevated CO2 cancelled each other out over an entire growing season, leading to no net effect of treatments on annual accumulation of greenness. The main effect of elevated CO2 dampened quickly, but warming continued to affect plant cover and plot greenness throughout the experiment. The combination of warming and elevated CO2 had a generally positive effect on greenness, especially early in the growing season and in later years of the experiment, enhanced annual greenness accumulation. However, interannual precipitation variation had larger effect on greenness, with two to three times greater greenness in wet years than in dry years., Synthesis. Seasonal variation in timing and amount of precipitation governs grassland phenology, greenness and the potential for carbon uptake. Our results indicate that concurrent changes in precipitation regimes mediate vegetation responses to warming and elevated atmospheric CO2 in semi-arid grasslands. Even small changes in vegetation phenology and greenness in response to warming and rising atmospheric CO2 concentrations, such as those we report here, can have large consequences for the future of grasslands. [ABSTRACT FROM AUTHOR]

Terrestrial plant and soil respiration, or ecosystem respiration (Reco), represents a major CO2 flux in the global carbon cycle. However, there is disagreement in how Reco will respond to future global changes, such as elevated atmosphere CO2 and warming. To address this, we synthesized six years (2007-2012) of Reco data from the Prairie Heating And CO2 Enrichment ( PHACE) experiment. We applied a semi-mechanistic temperature-response model to simultaneously evaluate the response of Reco to three treatment factors (elevated CO2, warming, and soil water manipulation) and their interactions with antecedent soil conditions [e.g., past soil water content ( SWC) and temperature (SoilT)] and aboveground factors (e.g., vapor pressure deficit, photosynthetically active radiation, vegetation greenness). The model fits the observed Reco well ( R2 = 0.77). We applied the model to estimate annual (March-October) Reco, which was stimulated under elevated CO2 in most years, likely due to the indirect effect of elevated CO2 on SWC. When aggregated from 2007 to 2012, total six-year Reco was stimulated by elevated CO2 singly (24%) or in combination with warming (28%). Warming had little effect on annual Reco under ambient CO2, but stimulated it under elevated CO2 (32% across all years) when precipitation was high (e.g., 44% in 2009, a 'wet' year). Treatment-level differences in Reco can be partly attributed to the effects of antecedent SoilT and vegetation greenness on the apparent temperature sensitivity of Reco and to the effects of antecedent and current SWC and vegetation activity (greenness modulated by VPD) on Reco base rates. Thus, this study indicates that the incorporation of both antecedent environmental conditions and aboveground vegetation activity are critical to predicting Reco at multiple timescales (subdaily to annual) and under a future climate of elevated CO2 and warming. [ABSTRACT FROM AUTHOR]

The woolly apple aphid ( WAA), Eriosoma lanigerum Hausmann, is a worldwide pest of apple orchards that has become widespread in apple-growing regions of Australia. Several WAA populations that are geographically distant may have evolved into biotypes having different fitness (e.g. fecundity) in similar biotic and abiotic conditions. In this study, we investigated the performance of four different lines of WAA (designated as ALB, STA, BAT and YAR) originating from four locations in Victoria and New South Wales ( Australia). Nymph establishment, nymph development to adult, nymph developmental time, female fecundity and adult weight of apterous virginoparae on apple trees (cv Granny Smith) were monitored under glasshouse conditions. Results showed that at least three lines examined here differ significantly in one or more performance parameters. Nymphs of the STA lineage showed a significantly higher establishment success after 7 days (64.3%) compared with lines BAT (53.1%) and YAR (43.6%). Nymph development to adulthood followed a similar trend. The average fecundity/female/7 days of the ALB lineage (19.7 ± 1.6 nymphs) was the lowest and significantly reduced relative to all other lines (from 36.6 to 40.5 nymphs). These results demonstrate the existence of at least three different biotypes in Australia. Antibiosis and antixenosis, respectively, could explain lower aphid establishment and lower female fecundity once settled. The characterisation of different WAA biotypes could have important implications for WAA management, and further studies should evaluate the overall diversity of biotypes, their geographical distribution and their growth characteristics to fully optimise pest control strategies. [ABSTRACT FROM AUTHOR]

Questions Woody plant encroachment into former grasslands currently represents a major physiognomic shift globally. Seedling establishment is a critical demographic bottleneck and is considered to be alleviated by increases in water availability and negatively impacted by interactions with grasses, particularly when water stress increases. However, interactions with grasses that are not actively competing for resources ('passive interactions' when grasses are dead) has seldom been considered. Could the transition from a live to a dead grass (litter) canopy favour recruitment of woody seedlings in a semi-arid grassland of the American SW? How does the sign and intensity of grass-seedling interactions change across drastically different summer precipitation regimes with and without passive interactions? Location Sonoran Desert shrub savanna at the Santa Rita Experimental Range, near Tucson, AZ, US. Methods Four cohorts of Prosopis velutina seeds were planted annually (2002-2005) under rainout shelters that intercepted all incoming precipitation on a soil with sandy loam texture. Summer precipitation was manipulated to simulate either a 50% increase or decrease in the long-term mean, and cover was manipulated to simulate a grassland dominated by the C4 bunchgrass Heteropogon contortus or left unvegetated. Emergence and survival of P. velutina was monitored and compared across cover types, along with monitoring of soil water content and light interception. Results Strong active competition was observed with live grasses, under both summer drought and also under ample summer water supply. However, the pattern was reversed and strong passive facilitation of P. velutina was observed over time when grass canopies died and remained in place. This passive facilitation under dry summers was so strong that recruitment under dead grass conditions was comparable to that observed when ample water supply removed the effects of competition on unvegetated plots. Conclusions After significant mortality of standing grass canopies, which typically compete for limited soil moisture resources, rates of recruitment by shrubs may increase even with significant seasonal drought. This work extends our understanding of interactions among co-located organisms and their effects on plant community dynamics, and introduces a new hypothesis on how grass litter facilitates woody plant encroachment during seasonal droughts. [ABSTRACT FROM AUTHOR]

The redheaded pasture cockchafer, Adoryphorus couloni ( Burmeister) ( Scarabaeidae: Dynastinae: Pentodontini) is a pest of semi-improved and improved pastures in south-eastern Australia. It is a native species that has adapted to managed pastures, and despite many years of research in attempts to control it, this species still causes major economic damage, especially to perennial dairy pastures in south-eastern Australia. This is a review of available information on A. couloni and identifies some basic information gaps that require addressing: correct identification of the main pasture beetles, more accurate detection and monitoring methods, and better information on its biology and ecology, especially its feeding behaviour in soil. [ABSTRACT FROM AUTHOR]

BACKGROUND With growing globalization and trade, insect incursions are increasing worldwide. A proportion of incursions involve pests of major economic crops (e.g. Mediterranean fruit fly), conservation value (e.g. tramp ants) or health significance (e.g. mosquitoes), and may be the targets of eradication programmes. Historically, such responses have included the use of broad-spectrum insecticides. However, with increasing public awareness of the negative aspects of pesticides, new environmentally friendly and effective techniques are needed. Here, we review and evaluate a range of selective to broad-spectrum tactical options for suppression which either have, or show potential for, integration within arthropod eradication programmes. RESULTS Most of the available technologies have their roots in pest management, but higher efficacy is required. Further refinement may be needed for use in eradication. Integration of several tactics is usually needed, as compatible tools can be used simultaneously to target different parts of the pest life cycle. However, not all technologies are fully compatible; for example, the simultaneous use of mass trapping and the sterile insect technique ( SIT) may be suboptimal, although sequential application may still be effective. CONCLUSIONS Broad-spectrum insecticides are generally incompatible with some biologically based technologies such as the SIT, but may be used to reduce the population so that density-dependent tactics can be used. Several novel technologies with fewer nontarget impacts have been proposed in recent years, and need to be properly evaluated for their applicability to insect eradication. Overall, there are still major gaps in surveillance and selective eradication technologies for most insects. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Eucalyptus species are grown widely outside of their native ranges in plantations on all vegetated continents of the world. We predicted that such a plantation species would show high potential for acclimation of photosynthetic traits across a wide range of growth conditions, including elevated [ CO2] and climate warming. To test this prediction, we planted temperate Eucalyptus globulus Labill. seedlings in climate-controlled chambers in the field located >700 km closer to the equator than the nearest natural occurrence of this species. Trees were grown in a complete factorial combination of elevated CO2 concentration ( eC; ambient [ CO2] +240 ppm) and air warming treatments ( eT; ambient +3 °C) for 15 months until they reached ca. 10 m height. There was little acclimation of photosynthetic capacity to eC and hence the CO2-induced photosynthetic enhancement was large (ca. 50%) in this treatment during summer. The warming treatment significantly increased rates of both carboxylation capacity ( Vcmax) and electron transport ( Jmax) (measured at a common temperature of 25 °C) during winter, but decreased them significantly by 20-30% in summer. The photosynthetic CO2 compensation point in the absence of dark respiration ( Γ*) was relatively less sensitive to temperature in this temperate eucalypt species than for warm-season tobacco. The temperature optima for photosynthesis and Jmax significantly changed by about 6 °C between winter and summer, but without further adjustment from early to late summer. These results suggest that there is an upper limit for the photosynthetic capacity of E. globulus ssp. globulus outside its native range to acclimate to growth temperatures above 25 °C. Limitations to temperature acclimation of photosynthesis in summer may be one factor that defines climate zones where E. globulus plantation productivity can be sustained under anticipated global environmental change. [ABSTRACT FROM AUTHOR]

As global changes reorganize plant communities, invasive plants may benefit. We hypothesized that elevated CO2 and warming would strongly influence invasive species success in a semi-arid grassland, as a result of both direct and water-mediated indirect effects., To test this hypothesis, we transplanted the invasive forb Linaria dalmatica into mixed-grass prairie treated with free-air CO2 enrichment and infrared warming, and followed survival, growth, and reproduction over 4 yr. We also measured leaf gas exchange and carbon isotopic composition in L. dalmatica and the dominant native C3 grass Pascopyrum smithii., CO2 enrichment increased L. dalmatica biomass 13-fold, seed production 32-fold, and clonal expansion seven-fold, while warming had little effect on L. dalmatica biomass or reproduction. Elevated CO2 decreased stomatal conductance in P. smithii, contributing to higher soil water, but not in L. dalmatica. Elevated CO2 also strongly increased L. dalmatica photosynthesis (87% versus 23% in P. smithii), as a result of both enhanced carbon supply and increased soil water., More broadly, rapid growth and less conservative water use may allow invasive species to take advantage of both carbon fertilization and water savings under elevated CO2. Water-limited ecosystems may therefore be particularly vulnerable to invasion as CO2 increases. [ABSTRACT FROM AUTHOR]

Nitrogen ( N) and phosphorus ( P) are essential nutrients for primary producers and decomposers in terrestrial ecosystems. Although climate change affects terrestrial N cycling with important feedbacks to plant productivity and carbon sequestration, the impacts of climate change on the relative availability of N with respect to P remain highly uncertain., In a semiarid grassland in Wyoming, USA, we studied the effects of atmospheric CO2 enrichment (to 600 ppmv) and warming (1.5/3.0°C above ambient temperature during the day/night) on plant, microbial and available soil pools of N and P., Elevated CO2 increased P availability to plants and microbes relative to that of N, whereas warming reduced P availability relative to N. Across years and treatments, plant N : P ratios varied between 5 and 18 and were inversely related to soil moisture., Our results indicate that soil moisture is important in controlling P supply from inorganic sources, causing reduced P relative to N availability during dry periods. Both wetter soil conditions under elevated CO2 and drier conditions with warming can further alter N : P. Although warming may alleviate N constraints under elevated CO2, warming and drought can exacerbate P constraints on plant growth and microbial activity in this semiarid grassland. [ABSTRACT FROM AUTHOR]

ABSTRACT Accurate estimates of the δ13C value of CO2 respired from roots ( δ13CR_root) and leaves ( δ13CR_leaf) are important for tracing and understanding changes in C fluxes at the ecosystem scale. Yet the mechanisms underlying temporal variation in these isotopic signals are not fully resolved. We measured δ13CR_leaf, δ13CR_root, and the δ13C values and concentrations of glucose and sucrose in leaves and roots in the C4 grass Sporobolus wrightii and the C3 tree Prosopis velutina in a savanna ecosystem in southeastern Arizona, USA. Night-time variation in δ13CR_leaf of up to 4.6 ± 0.6‰ in S. wrightii and 3.0 ± 0.6‰ in P. velutina were correlated with shifts in leaf sucrose concentration, but not with changes in δ13C values of these respiratory substrates. Strong positive correlations between δ13CR_root and root glucose δ13C values in P. velutina suggest large diel changes in δ13CR_root (were up to 3.9‰) influenced by short-term changes in δ13C of leaf-derived phloem C. No diel variation in δ13CR_root was observed in S. wrightii. Our findings show that short-term changes in δ13CR_leaf and δ13CR_root were both related to substrate isotope composition and concentration. Changes in substrate limitation or demand for biosynthesis may largely control short-term variation in the δ13C of respired CO2 in these species. [ABSTRACT FROM AUTHOR]

Attract-and-kill traps containing aggregation pheromone and food attractant have been developed in Australia to control Carpophilus spp. (Coleoptera: Nitidulidae) in orchards. Two field experiments were conducted in cherry and stone fruit orchards. One aimed to identify an appropriate size of orifice in co-attractant containers releasing either of two types of food attractants while keeping the amount of attractant fixed. Initial findings suggested that a 6.0 cm orifice was appropriate so another experiment was conducted to identify an appropriate amount of food attractant to be used in traps while keeping the size of orifice fixed at 6.0 cm. In experiment one, orifice sizes of 2.5 cm, 6.0 cm and 9.0 cm were used in traps baited with 120 mL of either fermented apple juice or liquid synthetic food attractant. Traps with a 6.0 cm orifice caught the most Carpophilus spp. followed by 9.0 cm and 2.5 cm but there were no significant differences in catch between the three orifice sizes. In experiment two, traps were baited with 120, 300 and 500 g or mL of either solid artificial beetle-rearing medium or liquid synthetic food attractant. Traps baited with synthetic solutions caught significantly ( P < 0.05) more beetles than traps baited with solid food medium except for the 500 g solid food traps. There were no significant differences in catch between the three amounts of synthetic solution. Traps with 500 g of solid food medium caught significantly ( P < 0.05) more beetles than those with 300 g and 120 g. [ABSTRACT FROM AUTHOR]

Attract and kill (A&K) is an effective control technique for Carpophilus spp. attacking stone fruit but high cost has limited its adoption by growers. Field experiments during two successive growing seasons evaluated the potential to reduce the spatial density of A&K traps from three traps per ha (3 A&K) to two traps per ha (2 A&K), against medium to low beetle populations. Fruit damage in 2 A&K and 3 A&K treated blocks was significantly lower than in pesticide-treated control blocks. However there were no significant differences in blocks treated with either 2 A&K or 3 A&K traps in either season. The results suggest that the number of traps per ha can be reduced without reducing the efficacy of the A&K treatment where Carpophilus population levels are medium to low. [ABSTRACT FROM AUTHOR]

Reliable estimation of insect population size is a pre-requisite to understand population dynamics and to develop management strategies for pest infestations. We report the results of three sampling studies to identify reliable methods of estimating the number of carpophilus beetles in traps. Study 1 compared reliability of volumetric and gravimetric methods. Fresh beetles and beetles dried for 24, 48 and 72 h were used. The reliability in terms of consistency and precision was quantified. A reliable method must first be consistent, quantified by a linear trend of zero slope. Volumetric methods using fresh and 24 h dried beetles were consistent and had good precision. Study 2 investigated the influence of sample size on reliability of volumetric estimation of number of fresh beetles using a 5 mL cylinder. Study 3 examined the influence of cylinder size on reliable volumetric estimation of 1000 fresh beetles. All three sample and cylinder sizes investigated were consistent and had good precision. These results suggest that volumetric methods are generally consistent and possess good precision, a 5 mL cylinder may be used for reliable volumetric estimation of up to 500 beetles, and a 50 mL cylinder may be used for reliable volumetric estimation of larger numbers of beetles. A model is developed to predict the number of fresh beetles from their measured volume. Advantages of volumetric methods compared with gravimetric methods are discussed. [ABSTRACT FROM AUTHOR]

We evaluated diurnal and seasonal patterns of carbon isotope composition of leaf dark-respired CO2 ( δ13Cl) in the C3 perennial shrub velvet mesquite ( Prosopis velutina) across flood plain and upland savanna ecosystems in the south-western USA. δ13Cl of darkened leaves increased to maximum values late during daytime periods and declined gradually over night-time periods to minimum values at pre-dawn. The magnitude of the diurnal shift in δ13Cl was strongly influenced by seasonal and habitat-related differences in soil water availability and leaf surface vapour pressure deficit. δ13Cl and the cumulative flux-weighted δ13C value of photosynthates were positively correlated, suggesting that progressive 13C enrichment of the CO2 evolved by darkened leaves during the daytime mainly resulted from short-term changes in photosynthetic 13C discrimination and associated shifts in the δ13C signature of primary respiratory substrates. The 13C enrichment of dark-respired CO2 relative to photosynthates across habitats and seasons was 4 to 6‰ at the end of the daytime period (1800 h), but progressively declined to 0‰ by pre-dawn (0300 h). The origin of night-time and daytime variations in δ13Cl is discussed in terms of the carbon source(s) feeding respiration and the drought-induced changes in carbon metabolism. [ABSTRACT FROM AUTHOR]

• The hypothesis that drought intensity constrains the recovery of photosynthesis from drought was tested in the C3 woody legume Prosopis velutina, and the mechanisms underlying this constraint examined. • Hydraulic status and gas exchange were measured the day before a 39 mm precipitation pulse, and up to 7 d afterwards. The experiment was conducted under rainout shelters, established on contrasting soil textures and with different vegetation cover at the Santa Rita Experimental Range in southeastern Arizona, USA. • Rates of photosynthesis and stomatal conductance after re-watering, as well as the number of days necessary for photosynthesis to recover after re-watering, were negatively correlated with predawn water potential, a measure of drought intensity ( R2 = 0.83, 0.64 and 0.92, respectively). • Photosynthetic recovery was incomplete when the vascular capacity for water transport had been severely impaired (percentage loss of hydraulic conductance > 80%) during the drought, which largely increased stomatal limitations. However, changes in biochemical capacity or in mesophyll conductance did not explain the observed pattern of photosynthesis recovery. Although the control that hydraulic limitations impose on photosynthesis recovery had been previously inferred, the first empirical test of this concept is reported here. [ABSTRACT FROM AUTHOR]

Field longevity of synthetic lures for Carpophilus spp. (Coleoptera: Nitidulidae) was evaluated by trapping studies in Australia, accompanied by chemical analyses. Carpophilus spp. are serious pests of ripening fruits, and an attract-and-kill method has been developed for their control. Traps are baited with one of two types of lure: synthetic pheromone (in rubber septa) and a host-related synthetic co-attractant (as an aqueous solution). No information was available on the longevity of either lure type. The objective of the study was to understand changes in attractiveness of the pheromone septa and co-attractant over time under field conditions. Pheromone septa were still attractive after 28 days in the field, but activity declined over time. Relative to fresh septa, catches in traps baited only with the pheromone declined to 75, 53, 32, 21, and 16% for 3-, 7-, 14-, 21-, and 28-day-old septa, respectively. Chemical emissions from aged septa showed a very similar decrease with time. Trap catches when both pheromone and co-attractant were present were far higher, and the decrease as the pheromone aged was less rapid (catches were 87, 73, 55, 44, and 36% of the original level for 3-, 7-, 14-, 21-, and 28-day-old septa, respectively). Apparently the presence of co-attractant could partially compensate for the deterioration of pheromone septa. The chemical changes of the co-attractant decreased more rapidly than the pheromone. In a laboratory study, two minor components (acetaldehyde and ethyl acetate) were essentially gone after 1 day, while the major component (ethanol) and the other three minor components (2-methyl-1-propanol, 3-methyl-1-butanol, and 2-methyl-1-butanol) were detectable for up to 4–8 days. Co-attractant evaporation was somewhat slower under field conditions. Trap catches for co-attractant of various ages and pheromones decreased three-fold as co-attractant age increased from 0 to 14 days. Implications with respect to beetle control are discussed. [ABSTRACT FROM AUTHOR]

Contents Severe droughts have been associated with regional-scale forest mortality worldwide. Climate change is expected to exacerbate regional mortality events; however, prediction remains difficult because the physiological mechanisms underlying drought survival and mortality are poorly understood. We developed a hydraulically based theory considering carbon balance and insect resistance that allowed development and examination of hypotheses regarding survival and mortality. Multiple mechanisms may cause mortality during drought. A common mechanism for plants with isohydric regulation of water status results from avoidance of drought-induced hydraulic failure via stomatal closure, resulting in carbon starvation and a cascade of downstream effects such as reduced resistance to biotic agents. Mortality by hydraulic failure per se may occur for isohydric seedlings or trees near their maximum height. Although anisohydric plants are relatively drought-tolerant, they are predisposed to hydraulic failure because they operate with narrower hydraulic safety margins during drought. Elevated temperatures should exacerbate carbon starvation and hydraulic failure. Biotic agents may amplify and be amplified by drought-induced plant stress. Wet multidecadal climate oscillations may increase plant susceptibility to drought-induced mortality by stimulating shifts in hydraulic architecture, effectively predisposing plants to water stress. Climate warming and increased frequency of extreme events will probably cause increased regional mortality episodes. Isohydric and anisohydric water potential regulation may partition species between survival and mortality, and, as such, incorporating this hydraulic framework may be effective for modeling plant survival and mortality under future climate conditions. [ABSTRACT FROM AUTHOR]

Three field experiments were conducted in stone fruit orchards in the Goulburn Valley, northern Victoria, Australia to identify a user-friendly trap for use in attract and kill stations for control of Carpophilus spp. (Coleoptera: Nitidulidae). A funnel trap design was compared with two types of delta trap in one experiment and two types of Lucitrap in another experiment. All traps were baited with synthetic co-attractant and synthetic pheromone. The funnel trap was the most effective type of trap tested. The funnel traps caught significantly more beetles than either the delta traps with bio-attractant or delta traps wrapped with insecticide impregnated banana wrap. No difference was observed between catches in either delta trap design. Lucitraps without covers caught significantly more beetles than Lucitraps with covers but funnel traps caught significantly more beetles than either type of Lucitrap. Beetle numbers caught in the funnel traps were three to five times higher than in Lucitrap. The use of funnel traps in attract and kill stations to protect stone fruit crops by suppressing the Carpophilus spp. population gave superior control to ‘grower normal practice of spraying insecticides’ both in terms of Carpophilus spp. numbers and in terms of reduction in percentage of fruit damaged. [ABSTRACT FROM AUTHOR]

Across many dryland regions, historically grass-dominated ecosystems have been encroached upon by woody-plant species. In this paper, we compare ecosystem water and carbon dioxide (CO2) fluxes over a grassland, a grassland–shrubland mosaic, and a fully developed woodland to evaluate potential consequences of woody-plant encroachment on important ecosystem processes. All three sites were located in the riparian corridor of a river in the southwest US. As such, plants in these ecosystems may have access to moisture at the capillary fringe of the near-surface water table. Using fluxes measured by eddy covariance in 2003 we found that ecosystem evapotranspiration (ET) and net ecosystem exchange of carbon dioxide (NEE) increased with increasing woody-plant dominance. Growing season ET totals were 407, 450, and 639 mm in the grassland, shrubland, and woodland, respectively, and in excess of precipitation by 227, 265, and 473 mm. This excess was derived from groundwater, especially during the extremely dry premonsoon period when this was the only source of moisture available to plants. Access to groundwater by the deep-rooted woody plants apparently decouples ecosystem ET from gross ecosystem production (GEP) with respect to precipitation. Compared with grasses, the woody plants were better able to use the stable groundwater source and had an increased net CO2 gain during the dry periods. This enhanced plant activity resulted in substantial accumulation of leaf litter on the soil surface that, during rainy periods, may lead to high microbial respiration rates that offset these photosynthetic fluxes. March–December (primary growing season) totals of NEE were −63, −212, and −233 g C m−2 in the grassland, shrubland, and woodland, respectively. Thus, there was a greater disparity between ecosystem water use and the strength of the CO2 sink as woody plants increased across the encroachment gradient. Despite a higher density of woody plants and a greater plant productivity in the woodland than in the shrubland, the woodland produced a larger respiration response to rainfall that largely offset its higher photosynthetic potential. These data suggest that the capacity for woody plants to exploit water resources in riparian areas results in enhanced carbon sequestration at the expense of increased groundwater use under current climate conditions, but the potential does not scale specifically as a function of woody-plant abundance. These results highlight the important roles of water sources and ecosystem structure on the control of water and carbon balances in dryland areas. [ABSTRACT FROM AUTHOR]

1 In water-limited ecosystems, discrete precipitation events trigger brief but important episodes of biological activity. Differential responses of above- and below-ground biota to precipitation may constrain biogeochemical transformations at the ecosystem scale. 2 We quantified short-term dynamics of whole ecosystem response to 39 mm irrigation events (precipitation pulses) during June 2002 and 2003 using plant physiological and ecosystem gas-exchange measurements as state variables in a principal components analysis (PCA). Experimental plots consisted of either native ( Heteropogon contortus L.) or non-native ( Eragrostis lehmanniana Nees) bunchgrasses planted in monoculture on two distinct geomorphic surfaces in a semi-arid grassland. 3 For 15 days, treatments followed similar, non-linear trajectories through state variable space with measurement periods forming distinct clusters; PCA axes 1 and 2 combined to explain 80.7% of the variation during both 2002 and 2003. 4 During both years, bunchgrass species interacted with soil type such that there was a reduction in ecosystem functional resistance in plots planted with the non-native bunchgrass species on the fine-textured clay geomorphic surface. 5 System-level hysteresis, emerging as a result of independent responses of photosynthesis, respiration and evapotranspiration to precipitation, indicated the potential for alternative functional states. 6 Quantifying the frequency and duration of ecosystem alternative functional states in response to individual precipitation events within a season will provide insights into the controls of species, soils and climate on ecosystem carbon and water cycles. [ABSTRACT FROM AUTHOR]

During two growing seasons, the use of an attract-and-kill system for control of Carpophilus spp. (Coleoptera: Nitidulidae) and the effective range or drawing power of the attract-and-kill stations were examined in stone fruit orchards in the Goulburn Valley, northern Victoria, Australia. Three attract-and-kill stations, baited with synthetic aggregation pheromone plus co-attractant, were placed about 50 m apart in the upwind corner of each treated block 5–6 weeks before the fruit began to ripen. Large numbers of Carpophilus spp. were caught in the attract-and-kill stations immediately after placement. By the time fruit had ripened, the number of Carpophilus spp. caught had decreased greatly. Fruit damage caused by Carpophilus spp. in treated blocks, especially in 2000–2001 season, was almost zero (0.1% and 0.6%) in trees and on the ground, respectively, whereas the damage levels in control blocks were 5.2% and 19.9% in trees and on the ground, respectively. This study indicates that excellent protection of ripening stone fruit may be achieved by using attract-and kill-stations. [ABSTRACT FROM AUTHOR]

Evaluates monsoon rain usage by dominant tree species of the pinyon-juniper ecosystem along a broad monsoon precipitation gradient in southwestern United States. Plant water potential and leaf gas exchange responses; Geographic differences in seasonal water use; Associations between functional rooting depth, drought tolerance and water-use efficiency.

Studies the role of phenotypic plasticity in the ecophysiology of introduced Pennisetum setaceum on Hawaii. Patterns of mortality; Physiological characteristics determined by environment; Total aboveground biomass at harvest; Statistical analysis.

The La (SS-B) autoimmune antigen is an RNA-binding protein that is present in both the nucleus and cytoplasm of eukaryotic cells, where it is found associated with RNA polymerase III transcripts. We have investigated the capacity of anti-La monoclonal antibodies SW1, SW3, and SW5 to immunoprecipitate human La ribonucleoprotein particles. Distinct differences were observed for SW3 in comparison with SW1 and SW5. While SW1 and SW5 precipitated ribonucleoproteins containing pre-tRNA, pre-5S rRNA, hY RNAs, pre-U6 snRNA or the viral EBER1 and VA RNAs, SW3 precipitated only ribonucleoproteins containing VA RNAs or (the precursor of) 7-2 RNA. Mapping of the epitopes recognized by SW1, SW3, and SW5 revealed that all three monoclonal antibodies recognize an epitope within the domain of the protein formed by the ribonucleoprotein motif. Cross-competition studies suggested that the epitope recognized by SW1 and SW5 are identical but distinct from the epitope recognized by SW3. Further analyses of the recognition of La from other species by these monoclonal antibodies revealed that they all reacted with bovine La and were not reactive with La from rodents and Xenopus laevis. Replacement of a single amino acid in the human protein by its murine counterpart abolished recognition by SW1 and SW5, but had no effect on recognition by SW3. Taken together, our results indicate that SW1 and SW5 recognize the same epitope and that SW3 recognizes a distinct epitope, both of which are located in the RNA-binding domain of La, and that the accessibility of these epitopes is differentially influenced by the association of La with various RNA polymerase III transcripts. [ABSTRACT FROM AUTHOR]

A creative partnership of public administration professionals and academics was formed to strengthen local management education in the state of West Virginia. The city manager practitioner group, a professional association of practitioners and academics, and the public administration program at the comprehensive state university joined together to improve understanding of and preparation for local government management. The cooperative effort to improve local management education and to extend practitioner-academic relationships was developed in the course of a number of meetings. The general goals of the cooperative effort were to interest and educate graduate public administration students in local management and to enrich the local management professionals and academics participating in the program. This program for improving local management education is readily adaptable to other locations and to other practitioner and academic groups. The major program components of practitioner taught seminars, intensive internships, colloquia and workshops, and student field research are easily modified to different situations.

BSTRACT: The development of policy in the American political system has been characterized by incremental change, creation of support, bargaining, compromise, pluralistic group interplay, development of social support and political support, technical input, review and consideration. Incrementalism, as it is called, allows policy to develop in tandem with technical knowledge, legislative and executive support, political advantage, and presumably greater certainty concerning the impact of a particular choice. Environmental policy development, one scholar has hypothesized, followed this basic pattern until the late 1960's when policy aspirations began to escalate much faster than the knowledge, organizational arrangements and political support upon which policy implementation depends. This 'escalation' hypothesis is examined in this paper, with particular attention given to policy development in West Virginia. [ABSTRACT FROM AUTHOR]