bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Performance of Administrative and Self‐Reported Measures for Risk Adjustment of Veterans Affairs Expenditures
Authors: Maciejewski Matthew L. , Liu Chuan‐Fen , Derleth Ann , McDonell Mary , Anderson Steve , Fihn Stephan D. 
Published: May 2005

Objective. To evaluate the performance of different prospective risk adjustment models of outpatient, inpatient, and total expenditures of veterans who regularly use Veterans Affairs (VA) primary care.Data Sources. We utilized administrative, survey and expenditure data on 14,449 VA patients enrolled in a randomized trial that gave providers regular patient health assessments.Study Design. This cohort study compared five administrative data‐based, two self‐report risk adjusters, and base year expenditures in prospective models.Data Extraction Methods. VA outpatient care and nonacute inpatient care expenditures were based on unit expenditures and utilization, while VA expenditures for acute inpatient care were calculated from a Medicare‐based inpatient cost function. Risk adjusters for this sample were constructed from diagnosis, medication and self‐report data collected during a clinical trial. Model performance was compared using adjusted R2 and predictive ratios.Principal Findings. In all expenditure models, administrative‐based measures performed better than self‐reported measures, which performed better than age and gender. The Diagnosis Cost Groups (DCG) model explained total expenditure variation (R2=7.2 percent) better than other models. Prior outpatient expenditures predicted outpatient expenditures best by far (R2=42 percent). Models with multiple measures improved overall prediction, reduced over‐prediction of low expenditure quintiles, and reduced under‐prediction in the highest quintile of expenditures.Conclusions. Prediction of VA total expenditures was poor because expenditure variation reflected utilization variation, but not patient severity. Base year expenditures were the best predictor of outpatient expenditures and nearly the best for total expenditures. Models that combined two or more risk adjusters predicted expenditures better than single‐measure models, but are more difficult and expensive to apply.
Survival Strategies for Michigan's Health Care Safety Net Providers
Authors: Jacobson Peter D. , Dalton Vanessa K. , Berson‐Grand Julie , Weisman Carol S. 
Published: May 2005

Objective. To understand key adaptive strategies considered by health care safety net organizations serving uninsured and underinsured populations in Michigan.Data Sources/Study Setting. Primary data collected through interviews at community‐based free clinics, family planning clinics, local public health departments, and Federally Qualified Health Centers from 2002 to 2003.Research Design. In each of six service areas in Michigan, we conducted a multiple‐site case study of the four organizations noted above. We conducted interviews with the administrator, the medical or clinical director, the financial or marketing director, and a member of the board of directors. We interviewed 74 respondents at 20 organizations.Principal Findings. Organizations perceive that unmet need is expanding faster than organizational capacity; organizations are unable to keep up with demand. Other threats to survival include a sicker patient population and difficulty in retaining staff (particularly nurses). Most clinics are adopting explicit business strategies to survive. To maintain financial viability, clinics are: considering or implementing fees; recruiting insured patients; expanding fundraising activities; reducing services; or turning away patients. Collaborative strategies, such as partnerships with hospitals, have been difficult to implement. Clinics are struggling with how to define their mission given the environment and threats to survival.Conclusions. Adaptive strategies remain a work in progress, but will not be sufficient to respond to increasing service demands. Increased federal funding, or, ideally, a national health insurance program, may be the only viable option for expanding organizational capacity.
Clay‐Turbid Interactions May Not Cascade—A Reminder for Lake Managers
Authors: Horppila Jukka , Liljendahl‐Nurminen Anne 
Published: May 2005

Abstract Food web management is a frequently used lake restoration method, which aims to reduce phytoplankton biomass by strengthening herbivorous zooplankton through reduction of planktivorous fish. However, in clay‐turbid lakes several factors may reduce the effectivity of food web management. Increasing turbidity reduces the effectivity of fish predation and weakens the link between zooplankton and phytoplankton. Therefore, the effects of fish stock manipulations may not cascade to lower trophic levels as expected. Additionally, in clay‐turbid conditions invertebrate predators may coexist in high densities with planktivorous fish and negate the effects of fish reductions. For instance, in the stratifying regions of the clay‐turbid Lake Hiidenvesi, Chaoborus flavicans is the main regulator of cladocerans and occupies the water column throughout the day, although planktivorous Osmerus eperlanus is very abundant. The coexistence of chaoborids and fish is facilitated by a metalimnetic turbidity peak, which prevents efficient predation by fish. In the shallow parts of the lake, chaoborids are absent despite high water turbidity. We suggest that, generally, the importance of invertebrate predators in relation to vertebrate predators may change along turbidity and depth gradients. The importance of fish predation is highest in shallow waters with low turbidity. When water depth increases, the importance of fish in the top‐down regulation of zooplankton declines, whereas that of chaoborids increases, the change along the depth gradient being moderate in clear‐water lakes and steep in highly turbid lakes. Thus, especially deep clay‐turbid lakes may be problematic for implementing food web management as a restoration tool.
Reestablishing Roots of a Mohawk Community and a Culturally Significant Plant: Sweetgrass
Authors: Shebitz Daniela J. , Kimmerer Robin W. 
Published: May 2005

Abstract The restoration potential of Sweetgrass (Anthoxanthum nitens (Weber) Y. Schouten & Veldkamp) was evaluated through a field experiment conducted on Kanatsiohareke, a Mohawk farm, and at the LaFayette Experiment Station near Syracuse, New York. The effects of competition reduction and two cover crops on Sweetgrass reestablishment success were examined. Sweetgrass was planted under four treatments: Sweetgrass alone; with existing, old‐field vegetation; with a cover crop of Hairy vetch (Vicia villosa); and with a cover crop of Annual (Italian) ryegrass (Lolium multiflorum). The experiment consisted of five replicates of the four treatments at both LaFayette and Kanatsiohareke. Sweetgrass biomass, height, reproduction rate, and survivorship were greatest in plots that were weeded to eliminate competition and in plots with Hairy vetch as a cover crop. A cover crop of Annual ryegrass resulted in reduced Sweetgrass growth and reproduction. The results of this field experiment indicate that there is great restoration potential for Sweetgrass because it is easily transplanted and reproduces vigorously. For 2.25‐m2 plots, Hairy vetch is an effective cover crop for Sweetgrass. Planting the Sweetgrass with Hairy vetch generated properties of the grass that are desired by basketmakers, such as abundance and tall blades. This technique also allowed for a relatively non–labor intensive method of cultivation. Reestablishment of Sweetgrass offers the members and visitors of Kanatsiohareke the means to continue to use the plant, strengthen traditional practices associated with Sweetgrass, and benefit economically by selling baskets and medicine made with Sweetgrass.
Coastal Dune Forest Development and the Regeneration of Millipede Communities
Authors: Redi Bereket H. , Van Aarde Rudi J. , Wassenaar Theo D. 
Published: May 2005

AbstractThe rehabilitation of disturbed ecosystems through ecological succession should lead to the recovery of indigenous biological assemblages typical of a region. However, rehabilitation may give rise to unusual successional pathways and lead to atypical assemblages. We compared millipede assemblages along a chronosequence of habitats developing in response to a post‐mining coastal dune forest rehabilitation program with those developing spontaneously in the same area. Our comparison suggests that active rehabilitation mimics and even surpasses spontaneous successional development. On both chronosequences, the total number of species, as well as the mean density, diversity, and species richness increased, and dominance decreased, with habitat regeneration age. Moreover, the similarity of millipede assemblages on the two chronosequences to those on three sets of reference sites (mature forests) increased with regeneration age, but this recovery of community composition occurred faster on the rehabilitating chronosequence than on the spontaneously regenerating chronosequence. This suggests that successional processes are leading to a recovery of the predisturbed state, but factors like protection from further disturbances, which occur on the spontaneously regenerating chronosequence, is probably important to ensure success. The distance between a regenerating site and a colonization source area apparently affects the direction of community recovery—assemblages on the rehabilitating chronosequence converged faster onto assemblages on closer reference sites than onto those on reference sites farther away.
Establishing Native Grasses in a Big Sagebrush–Dominated Site: An Intermediate Restoration Step
Authors: Huber‐Sannwald Elisabeth , Pyke David A. 
Published: May 2005

AbstractMany semiarid rangelands in the Great Basin, U.S.A., are shifting dominance to woody species as a consequence of land degradation including intense livestock grazing and fire suppression. Whereas past rehabilitation efforts in Big sagebrush (Artemisia tridentata) steppes removed the shrub and added introduced forage grasses to successfully shift communities from shrublands to grasslands, current consensus is that native species should be included in restoration projects and that retention of some woody plants is desirable. We examined the potential for interseeding grasses into dense shrub communities as a precursor to thinning shrubs and releasing grasses from shrub interference. We compared seedling establishment of the native grass, Bluebunch wheatgrass (Pseudoroegneria spicata), with that of the Eurasia grass, Crested wheatgrass (Agropyron desertorum), in denseAr. tridentatastands. Shrubs may play an important role as nurse plants for seedling establishment (reduced solar radiation, “island of fertility” effect) but result in highly contrasting light environments and root interference for seedlings. In experimental plots, we examined effects ofAr. tridentatashade levels (0, 40, 70, and 90% reduction of solar radiation) and initial root exclusion (present/absent) on the establishment and growth ofP. spicataandAg. desertorumseedlings. With this design we evaluated the interference effects ofAr. tridentataon the two grasses and identified the most beneficial microsites for grass restoration inAr. tridentata–dominated communities. We predicted seedling survival and growth to be greater under moderate shade (40% reduction) and limited root competition than under no or strong shade conditions (0 and 90%) and unrestricted root interactions. Fifty to 85% of theP. spicataandAg. desertorumseedlings survived the dry summer months of 1995 and 1996 and the intervening winter. Neither shading nor root exclusion fromAr. tridentataaffected final seedling survival of either species. Seedling biomass of both grass species was negatively affected by initial root interactions withAr. tridentata.However, the analysis of seedling biomass variability (coefficient of variation) indicated that in all shade and root‐exclusion treatments, some seedlings of both species developed to large individuals to survive inAr. tridentata–dominated rangelands. Thus, the use of interseeding techniques shows promise for restoring herbaceous species in denseAr. tridentatastands and should be given further consideration when shrub retention is an important consideration.
Implications of Food Web Interactions for Restoration of Missouri Ozark Glade Habitats
Authors: Van Zandt Peter A. , Collins Eboni , Losos Jonathan B. , Chase Jonathan M. 
Published: May 2005

Abstract Ozark glades are gaps in forested areas that are dominated by grasses and forbs growing in rocky, nutrient‐poor soil. Historically, these open, patchy habitats were maintained by natural and anthropogenic fire cycles that prohibited tree encroachment. However, because of decades of fire suppression, glades have become overgrown by fire‐intolerant species such as Eastern red cedar (Juniperus virginiana). Current restoration practices include cutting down invasive cedars and burning brush piles, which represent habitat for Northern fence lizards (Sceloporus undulatus). Because Sceloporus actively consumes herbivores, we hypothesized that the presence of these lizards in and around brush piles might result in a trophic cascade, whereby damage on native plants is reduced. Field surveys across six Missouri glades indicated that lizard activity was minimal beyond 1 m from habitat structures. This activity pattern reduced grasshopper abundance by 75% and plant damage by over 66% on Echinacea paradoxa and Rudbeckia missouriensis near structures with lizards. A field transplant experiment demonstrated similar reductions in grasshopper abundance and damage on two other glade endemic species, Aster oblongifolius and Schizachyrium scoparium. These results demonstrate that future glade restoration efforts might benefit from considering top‐down effects of predators in facilitating native plant establishment.
Effects of Mycorrhizae and Nontarget Organisms on Restoration of a Seasonal Tropical Forest in Quintana Roo, Mexico: Factors Limiting Tree Establishment
Authors: Allen Michael F. , Allen Edith B. , Gómez‐Pompa Arturo 
Published: May 2005

AbstractWe initiated a study of the effects of mycorrhizal fungal community composition on the restoration of tropical dry seasonal forest trees. Tree seedlings were planted in a severely burned experimental site (1995 fire) during the growing season of 1998 at the El Edén Ecological Reserve, in north Quintana Roo, Mexico. Seedlings ofLeucaena leucocephala,Guazuma ulmifolia,Caesalpinia violacea,Piscidia piscipula,Gliricidia sepium, andCochlospermum vitifoliumwere germinated in steam‐sterilized soil and either remained uninoculated (nonmycorrhizal at transplanting) or were inoculated with mycorrhizal fungi in soils from early‐seral (recently burned) or late‐seral (mature forest) inoculum. Inoculum from the early‐seral soil was largelyGlomusspp., whereas a diverse community of arbuscular mycorrhizal fungi were reintroduced from the mature forest including species ofScutellospora,Gigaspora,Glomus, Sclerocystis, andAcaulospora. Plants grew better when associated with the mature forest inoculum, unlike a previous experiment in which plants grew taller with the early‐seral inoculum. Reasons for the different responses include a less‐intense burn resulting in more residual organic matter. In addition to mycorrhizal responses, plants were severely affected by deer browsing. One tree species,C. vitifoliumfound in the region but not in the reserve, was eliminated by a resident fungal facultative pathogen. Several practical conclusions for restoration can be made. The common nursery practice of soil sterilization may be detrimental because it eliminates beneficial mycorrhizal fungi; species not native to the site may not survive because they may not be adapted to the local pathogens; and herbivory can be severe depending on the landscape context of the restoration.
Forest Restoration in Urbanizing Landscapes: Interactions Between Land Uses and Exotic Shrubs
Authors: Borgmann Kathi L. , Rodewald Amanda D. 
Published: May 2005

Abstract Preventing and controlling exotic plants remains a key challenge in any ecological restoration, and most efforts are currently aimed at local scales. We combined local‐ and landscape‐scale approaches to identify factors that were most closely associated with invasion of riparian forests by exotic shrubs (Amur honeysuckle [Lonicera maackii] and Tatarian honeysuckle [L. tatarica]) in Ohio, U.S.A. Twenty sites were selected in mature riparian forests along a rural–urban gradient (<1–47% urban land cover). Within each site, we measured percent cover of Lonicera spp. and native trees and shrubs, percent canopy cover, and facing edge aspect. We then developed 10 a priori models based on local‐ and landscape‐level variables that we hypothesized would influence percent cover of Lonicera spp. within 25 m of the forest edge. To determine which of these models best fit the data, we used an information‐theoretic approach and Akaike's information criterion. Percent cover of Lonicera was best explained by the proportion of urban land cover within 1 km of riparian forests. In particular, percent cover of Lonicera was greater in forests within more urban landscapes than in forests within rural landscapes. Results suggest that surrounding land uses influence invasion by exotic shrubs, and explicit consideration of land uses may improve our ability to predict or limit invasion. Moreover, identifying land uses that increase the risk of invasion may inform restoration efforts.
Hydrologic Regime Controls Soil Phosphorus Fluxes in Restoration and Undisturbed Wetlands
Authors: Aldous Allison , McCormick Paul , Ferguson Chad , Graham Sean , Craft Chris 
Published: May 2005

Abstract Many wetland restoration projects occur on former agricultural soils that have a history of disturbance and fertilization, making them prone to phosphorus (P) release upon flooding. To study the relationship between P release and hydrologic regime, we collected soil cores from three restoration wetlands and three undisturbed wetlands around Upper Klamath Lake in southern Oregon, U.S.A. Soil cores were subjected to one of three hydrologic regimes—flooded, moist, and dry—for 7.5 weeks, and P fluxes were measured upon reflooding. Soils from restoration wetlands released P upon reflooding regardless of the hydrologic regime, with the greatest releases coming from soils that had been flooded or dried. Undisturbed wetland soils released P only after drying. Patterns in P release can be explained by a combination of physical and biological processes, including the release of iron‐bound P due to anoxia in the flooded treatment and the mineralization of organic P under aerobic conditions in the dry treatment. Higher rates of soil P release from restoration wetland soils, particularly under flooded conditions, were associated with higher total P concentrations compared with undisturbed wetland soils. We conclude that maintaining moist soil is the means to minimize P release from recently flooded wetland soils. Alternatively, prolonged flooding provides a means of liberating excess labile P from former agricultural soils while minimizing continued organic P mineralization and soil subsidence.
Removal of Encroaching Conifers to Regenerate Degraded Aspen Stands in the Sierra Nevada
Authors: Jones Bobette E. , Rickman Tom H. , Vazquez Alfred , Sado Yukako , Tate Kenneth W. 
Published: May 2005

Abstract Aspen is considered a keystone species, and aspen communities are critical for maintaining biodiversity in western landscapes. Inventories of aspen stand health across the Eagle Lake Ranger District (ELRD), Lassen National Forest, California, U.S.A., indicate that 77% of stands are in decline and at risk of loss as defined by almost complete loss of mature aspen with little or no regeneration. This decline is due to competition from conifers establishing within aspen stands as a result of modification of natural fire regimes coupled with excessive browsing by livestock. Restoration treatments were implemented in four aspen stands in 1999 using mechanical equipment to remove competing conifers to enhance the growth environment for aspen. Recruitment and establishment of aspen stems were measured in treated stands (removal of competing conifers) and non‐treated stands (control) immediately prior to treatment and 2 and 4 years post‐treatment. There was a significant increase in total aspen stem density and in two of three aspen regeneration size classes for treated stands compared to controls. Pre‐treatment total aspen density was positively associated with total aspen density and density in all size classes of aspen (p < 0.001). The results demonstrate that mechanical removal of conifers is an effective treatment for restoring aspen.
Importance of Hydrologic and Landscape Heterogeneity for Restoring Bank Swallow (Riparia riparia) Colonies along the Sacramento River, California
Authors: Moffatt Kerry C. , Crone Elizabeth E. , Holl Karen D. , Schlorff Ronald W. , Garrison Barrett A. 
Published: May 2005

AbstractHuman activities have degraded riparian systems in numerous ways, including homogenization of the floodplain landscape and minimization of extreme flows. We analyzed the effects of changes in these and other factors for extinction–colonization dynamics of a threatened Bank Swallow population along the upper Sacramento River, California, U.S.A. We monitored Bank Swallow distributions along a 160‐km stretch of the river from 1986–1992 and 1996–2003 and tested whether site extinctions and colonizations corresponded with changes in maximum river discharge, surrounding land cover, estimated colony size, temperature, and precipitation. Colonization probabilities increased with maximum discharge. Extinction probabilities decreased with proximity to the nearest grassland, decreased with colony size, and increased with maximum discharge. To explore the implications for restoration, we incorporated the statistically estimated effects of distance to grassland and maximum discharge into simple metapopulation models. Under current conditions, the Bank Swallow metapopulation appears to be in continued decline, although stable or increasing numbers cannot be ruled out with the existing data. Maximum likelihood parameters from these regression models suggest that the Sacramento River metapopulation could be restored to 45 colonies through moderate amounts of grassland restoration, large increases in discharge, or direct restoration of nesting habitat by removing approximately 10% of existing bank protection (riprap) from suitable areas. Our results highlight the importance of grassland restoration, mixed benefits of restoring high spring discharge, and the importance of within‐colony dynamics as areas for future research.