bluuebunny/crossref_metadata_2025_split huggingface dataset:
Simulated Herbivory and Vegetation Dynamics in Coal Slurry Ponds Reclaimed as Wetlands
Authors: Mathis Marilyn J. , Middleton Beth A. 
Published: March 2003

AbstractThe biodiversity of coal slurry ponds can be inhibited, at least in part, by dense stands of Phragmites australis. In this study, we demonstrate that species richness can be increased in coal slurry ponds if the dominant species (P. australis and Typha latifolia) are removed and that underwater herbivory simulated by cutting will kill emergents. The study was conducted in the greenhouse and the field in both flooded and drawndown conditions. Stems of plants of P. australis and T. latifolia were cut in a greenhouse and the cut plants of both species showed a decline in survivorship (25 and 42% survival, respectively) whereas all uncut plants survived. In a reclaimed coal pond at Pyramid State Park, Illinois, neither P. australis nor T. latifolia survived cutting underwater, but all of the uncut plants survived. Regrowth measured as total biomass of stems was less among flooded versus freely drained plants (0.3 and 2.6 g biomass, respectively). Cut versus uncut plants, combining freely drained and flooded, had less below‐ground biomass (99.4 and 254.4 g, respectively). In the greenhouse study, oxygen levels in rhizomes subsequent to cutting were measured using an oxygen electrode and millivolt meter. Oxygen levels in P. australis were lower in cut versus uncut plants both in flooded (15.0 vs. 16.3% ambient O2, respectively) and freely drained conditions (14.5 vs. 15.0%, ambient O2, respectively). Similar responses to cutting were demonstrated by T. latifolia. In an unreclaimed coal slurry pond with monospecific stands of P. australis, plant species richness increased in cut plots as compared to uncut plots (29 vs. 2 species, respectively) between March and September, 1995. This study demonstrated that species richness can be increased in coal ponds by mechanical cutting and this potentially by herbivory; however, the additional species were mostly exotics.
Effects of Nursery Pre‐Conditioning on Panicum hemitomon and Sagittaria lancifolia Used for Wetland Restoration
Authors: Pezeshki S. R. , Anderson P. H. , DeLaune R. D. 
Published: March 2003

AbstractA study was conducted to examine nursery protocols for production of planting stocks used in wetland mitigation projects. Two commercial soil mixtures were tested along with waterlogging, fertilization, and combination treatments. Two marsh species, Panicum hemitomon and Sagittaria lancifolia, were subjected to a two‐phase study. During Phase I, watering and fertilization treatments were applied in a 2 × 2 × 2 factorial design with two soils, two watering regimes, and two fertilizer treatments. In Phase II, all plants were subjected to continuous waterlogging (no fertilizer). Soil redox potential was measured, along with plant gas exchange and growth responses. Our data do not support the hypothesis that flood “pre‐conditioning” alone can significantly improve plant growth under subsequent flooding. However, fertilization alone or in combination with flooding appeared to enhance shoot and root production in both species during the subsequent flooding. In contrast, flooding alone produced Panicum plants that appeared to remain somewhat susceptible to subsequent flooding as compared to fertilized plants. Sagittaria plants subjected to fertilizer treatment alone did not produce significantly greater total dry weights compared to their controls. Our data indicate that the growth of planting stocks for wetland mitigation can be improved by fertilization in the nursery.Key words: fertilizer, flooding, nursery production, wetland mitigation.
Effects of Resource‐Island Soils, Competition, and Inoculation with Azospirillum on Survival and Growth of Pachycereus pringlei, the Giant Cactus of the Sonoran Desert
Authors: Carrillo‐Garcia Ángel , Bashan Yoav , Rivera Ernesto Díaz , Bethlenfalvay Gabor J. 
Published: March 2003

AbstractResource‐island soils formed by some plants in arid lands are capable of supporting certain plants that do not normally establish in surrounding areas free of vegetation. We determined growth responses of Pachycereus pringlei (cardon), the giant columnar cactus, whose widespread, finely branched, subsurface root systems stabilize desert soils, to four soils collected from within or outside of resource islands. Traits of cardon grown in soils from mature (MM) or young (YM) Prosopis articulata (mesquite), mature Olnea testosa (ironwood, MI), or bare areas (BA) were compared, to determine differences between the effects of soils due to the identity or the stage of development of nurse plants. The levels of soil N, P, and C contents were in the order MM> > YM > MI BA. The BA soil had the coarsest and MM soil the finest texture. Cardon was also grown in pot cultures inoculated with the plant‐growth‐promoting bacterium Azospirillum brasilense, or in association with a competing grass, Sorghum bicolor (sorghum). Competition did not affect survival rates of cardon in any of the soils after six months of growth, but decreased biomass accumulation by up to 90% in the best (MM) soil. Inoculation of cardon seeds with A. brasilense did not affect survival but resulted in significantly better root and shoot growth, and this effect increased linearly as soil nutrients declined. In the best soil (MM), A. brasilense had no effect on cardon growth, but in the poorest soil (BA) shoot dry mass was almost 60% and root length over 100% greater as a result of inoculation, with responses in the other two soils intermediate. This effect did not appear to be owing to N2 fixation, as nitrogenase activity (acetylene reduction) was not detected in any of the treatments. Soil formation by selected nurse trees in arid areas is an important factor in plant establishment and growth, and the present results indicate that these processes can be impeded or facilitated by the introduction of competing or beneficial organisms. The use of beneficial microorganisms associated with roots may accelerate the restoration of disturbed areas.Key words: Azospirillum, desert soils, nitrogen fixation, nurse plant, Pachycereus pringlei, plant survival, resource‐island.
The Use of Mixtures of Sulfur and Bracken Litter to Reduce pH of Former Arable Soils and Control Ruderal Species
Authors: Owen K. M. , Marrs R. H. 
Published: March 2003

AbstractHigh soil pH has been highlighted as a constraint to the restoration of heathland on ex‐arable land. Previous studies at the Minsmere Reserve of the Royal Society for the Protection of Birds (RSPB) in England have shown that it is possible to acidify ex‐arable soils using elemental sulfur and bracken litter, although sulfur (S) is more effective. Current recommendations suggest that 4 tS/ha need to be applied to reduce soil pH below pH 4, control vigorous ruderal species, and create conditions suitable for Calluna vulgaris (heather) establishment. However, S is relatively expensive, and as bracken litter is moderately abundant within the reserve, it made economic sense to evaluate the potential for mixing S with bracken to see if adequate pH reductions could be achieved at lower S rates. Accordingly an experiment was designed to test the effects of combining S (0–8 t S/ha) and bracken litter (0–10 cm depth layers) on (1) soil pH, (2) cover of ruderal species, and (3) the developing plant community. Significant interactions were detected, especially in the period immediately after application. Where bracken litter was applied the soil pH fell immediately; in contrast, S took at least six months to start reducing pH. Where mixtures were applied there was a synergistic effect, which produced a lower pH than the S or bracken litter applied alone. These effects were most marked at low S application rates, between 0.5–4 t S/ha. The effects of the bracken litter addition also reduced the growth of ruderal species in the period immediately after application, probably through a combination of acidification and physical smothering. There is, therefore, a clear potential to acidify ex‐arable soils using combinations of S and bracken litter in schemes designed to restore Calluna heathland.
Effects of Grazing on Restoration of Southern Mixed Prairie Soils
Authors: Fuhlendorf Samuel D. , Zhang Hailin , Tunnell Tim. R. , Engle David M. , Cross Anne Fernald 
Published: March 2003

AbstractA comparative analysis of soils and vegetation from cultivated areas reseeded to native grasses and native prairies that have not been cultivated was conducted to evaluate restoration of southern mixed prairie of the Great Plains over the past 30 to 50 years. Restored sites were within large tracts of native prairie and part of long‐term grazing intensity treatments (heavy, moderate, and ungrazed), allowing evaluation of the effects of grazing intensity on prairie restoration. Our objective was to evaluate restored and native sites subjected to heavy and moderate grazing regimes to determine if soil nutrients from reseeded cultivated land recovered after 30 years of management similar to the surrounding prairie and to identify the interactive influence of different levels of grazing and history of cultivation on plant functional group composition and soils in mixed prairies. For this mixed prairie, soil nitrogen and soil carbon on previously cultivated sites was 30 to 40% lower than in uncultivated native prairies, indicating that soils from restored sites have not recovered over the past 30 to 50 years. In addition, it appears that grazing alters the extent of recovery of these grassland soils as indicated by the significant interaction between grazing intensity and cultivation history for soil nitrogen and soil carbon. Management of livestock grazing is likely a critical factor in determining the potential restoration of mixed prairies. Heavy grazing on restored prairies reduces the rate of soil nutrient and organic matter accumulation. These effects are largely due to changes in composition (reduced tallgrasses), reduced litter accumulation, and high cover of bare ground in heavily grazed restored prairies. However, it is evident from this study that regardless of grazing intensity, restoration of native prairie soils requires many decades and possibly external inputs to adequately restore organic matter, soil carbon, and soil nitrogen.
Contrasting Functional Performance of Juvenile Salmon Habitat in Recovering Wetlands of the Salmon River Estuary, Oregon, U.S.A.
Authors: Gray Ayesha , Simenstad Charles A. , Bottom Daniel L. , Cornwell Trevan J. 
Published: March 2003

AbstractFor an estuarine restoration project to be successful it must reverse anthropogenic effects and restore lost ecosystem functions. Restoration projects that aim to rehabilitate endangered species populations make project success even more important, because if misjudged damage to already weakened populations may result. Determining project success depends on our ability to assess the functional state or “performance” and the trajectory of ecosystem development. Mature system structure is often the desired “end point” of restoration and is assumed to provide maximum benefit for target species; however, few studies have measured linkages between structure and function and possible benefits available from early recovery stages. The Salmon River estuary, Oregon, U.S.A., offers a unique opportunity to simultaneously evaluate several estuarine restoration projects and the response of the marsh community while making comparisons with a concurring undiked portion of the estuary. Dikes installed in three locations in the estuary during the early 1960s were removed in 1978, 1987, and 1996, creating a “space‐for‐time substitution” chronosequence. Analysis of the marsh community responses enables us to use the development state of the three recovering marshes to determine a trajectory of estuarine recovery over 23 years and to make comparisons with a reference marsh. We assessed the rate and pattern of juvenile salmon habitat development in terms of fish density, available prey resources, and diet composition of wild juvenile Oncorhynchus tshawytscha (chinook salmon). Results from the outmigration of 1998 and 1999 show differences in fish densities, prey resources, and diet composition among the four sites. Peaks in chinook salmon densities were greatest in the reference site in 1998 and in the youngest (1996) site in 1999. The 1996 marsh had higher densities of chironomids (insects; average 864/m2) and lower densities of amphipods (crustaceans; average 8/m3) when compared with the other sites. Fauna differences were reflected in the diets of juvenile chinook with those occupying the 1978 and 1996 marshes based on insects (especially chironomids), whereas those from the 1987 and reference marshes were based on crustaceans (especially amphipods). Tracking the development of recovering emergent marsh ecosystems in the Salmon River estuary reveals significant fish and invertebrate response in the first 2 to 3 years after marsh restoration. This pulse of productivity in newly restored systems is part of the trajectory of development and indicates some level of early functionality and the efficacy of restoring estuarine marshes for juvenile salmon habitat. However, to truly know the benefits consumers experience in recovering systems requires further analysis that we will present in forthcoming publications.
Avian Response to Bottomland Hardwood Reforestation: The First 10 Years
Authors: Twedt Daniel J. , Wilson R. Randy , Henne‐Kerr Jackie L. , Grosshuesch David A. 
Published: March 2003

AbstractBottomland hardwood forests were planted on agricultural fields in Mississippi and Louisiana predominantly using either Quercus species (oaks) or Populus deltoides (eastern cottonwood). We assessed avian colonization of these reforested sites between 2 and 10 years after planting. Rapid vertical growth of cottonwoods (circa 2–3 m/year) resulted in sites with forest structure that supported greater species richness of breeding birds, increased Shannon diversity indices, and supported greater territory densities than on sites planted with slower‐growing oak species. Grassland birds (Spiza americana[Dickcissel] and Sturnella magna[Eastern Meadowlark]) were indicative of species breeding on oak‐dominated reforestation no more than 10 years old. Agelaius phoeniceus (Red‐winged Blackbird) and Colinus virginianus (Northern Bobwhite) characterized cottonwood reforestation no more than 4 years old, whereas 14 species of shrub‐scrub birds (e.g., Passerina cyanea[Indigo Bunting]) and early‐successional forest birds (e.g., Vireo gilvus[Warbling vireo]) typified cottonwood reforestation 5 to 9 years after planting. Rates of daily nest survival did not differ between reforestation strategies. Nest parasitism increased markedly in older cottonwood stands but was overwhelmed by predation as a cause of nest failure. Based on Partners in Flight prioritization scores and territory densities, the value of cottonwood reforestation for avian conservation was significantly greater than that of oak reforestation during their first 10 years. Because of benefits conferred on breeding birds, we recommend reforestation of bottomland hardwoods should include a high proportion of fast‐growing early successional species such as cottonwood.
Smoke, Mulch, and Seed Broadcasting Effects on Woodland Restoration in Western Australia
Authors: Rokich Deanna P. , Dixon Kingsley W. , Sivasithamparam K. , Meney Kathy A. 
Published: March 2003

AbstractSmoke, canopy‐derived mulch, and broadcast seeds were used to maximize the establishment of Banksia woodland species in sand quarries in Western Australia. Smoke, particularly aerosol smoke, had a positive effect on total seedling recruitment. Pre‐mined (woodland) sites showed a 42‐fold increase in total germinants and a 3‐fold increase in the number of species with aerosol smoke application. Post‐mined (restored) sites showed only a 3.6‐fold increase in total germinants and a 1.4‐fold increase in the number of species. Two water‐based smoke chemicals, DC10 (pH 4.5) and SC63 (pH 2.5), increased seedling recruitment at both sites but were not as effective in stimulating recruitment as aerosol smoke. Neither of the chemicals were effective in significantly increasing species richness. Application of aerosol smoke directly to seeds as a pretreatment before broadcasting had no effect on seedling recruitment. Broadcasting of seeds onto restoration sites significantly increased seedling abundance and richness. Application of a single layer of mulch from the canopy vegetation after seed broadcasting gave optimum seedling recruitment. Two layers of mulch significantly reduced recruitment, as did applying mulch before seed broadcasting. For broad‐scale restoration, the application of smoke on newly restored sites would be more effectively achieved using smoke water sprayed over the soil surface. Species that do not recruit from replaced topsoil could be effectively recovered from broadcast seed rather than from mulch.
Patterns of Onset of Disability in Activities of Daily Living with Age
Authors: Jagger Carol , Arthur Antony J. , Spiers Nicola A. , Clarke Michael 
Published: March 2003

OBJECTIVES: To investigate the order in which activities of daily living (ADLs) are lost and whether the order is invariant between the sexes and age groups.DESIGN: Longitudinal data from the first five rounds of a routine health assessment by a nurse in participant's own home.SETTING: One large UK general practice with a list size of 32,500.PARTICIPANTS: Patients registered with the practice and age 75 and older.MEASUREMENTS: Disability was measured by self‐report of performance in seven ADLs: mobility around the home, getting to and from the toilet, transfer from chair, transfer from bed, feeding, dressing, and bathing. Disability in each ADL was classified as being independent but having difficulty, using aids or help, or being unable to perform. Age at onset of disability in each ADL was calculated and analyzed using Kaplan‐Meier plots and Cox regression models. Subjects who had died or remained independent by their last assessment were not included.RESULTS: The mean times between health assessments was approximately 20 months but with substantial variability both within and between individuals. A total of 1,344 people reported no difficulty in any ADL initially and 47.6% (640) subsequently reported disability. The order of activity restriction was bathing, mobility, toileting, dressing, transfers from bed and chair, and feeding. Women had a higher risk of disability in bathing (relative risk (RR) = 1.6, 95% confidence interval (CI) 1.3–1.9, P < .001) and toileting (RR = 1.7, 95% CI 1.2–2.5, P = .003), while for all ADLs there was a significant increase in the risk of disability with increasing age. The order of onset of disability for ADLs was invariant across sex and age groups.CONCLUSION: Lower‐extremity strength (bathing, mobility, toileting) appears to be lost in older people before upper‐extremity strength (dressing, feeding). Further work is now needed to develop prevention strategies to delay the onset of these disabilities.
Physician Visits, Emergency Room Utilization, and Overnight Hospitalization in the Old‐Old in Israel: The Cross‐Sectional and Longitudinal Aging Study (CALAS)
Authors: Walter‐Ginzburg Adrian , Chetrit Angela , Medina Chaya , Blumstein Tzvia , Gindin Jacob , Modan Baruch 
Published: March 2003

OBJECTIVES:The objective of this paper is to assess the risk factors for physician contact in the month before the interview (PM) and emergency room utilization (ERU) and overnight hospitalization (OH) in the year before the interview, through the use of the behavioral model as a conceptual framework.DESIGN:A random stratified sample of subjects age 75 to 94 was selected from the National Population Register (a complete listing of the Israeli population maintained by the Ministry of the Interior). The study sample consisted of Jews living in Israel on January 1, 1989, stratified by age (four 5‐year age groups: 75–79, 80–84, 85–89, and 90–94), sex, and place of birth (Europe/America, Asia/Africa, and Israel).SETTING:Community‐dwelling old‐old Jewish Israelis.PARTICIPANTS:1,487 people living in the community at the time of the baseline interview.MEASUREMENTS:The dependent variables were PM in the month before the interview and ERU and OH in the previous year. The independent variables were: predisposing variables (age, sex, place of birth, and education); enabling variables (income and the social network variables of marital status, living arrangements, and number of in‐person contacts per week with any child); and need variables (number of self‐reported chronic medical conditions, subjective health, depressive symptoms, number of difficulties with activities of daily living and instrumental activities of daily living, measures of physical robustness, and engaging in regular physical sportive activities).RESULTS:The predisposing and enabling factors were only minimally associated with utilization rates in the old old in Israel, with the exception of lower rates of ERU by those who were living alone. Age was not significantly associated with healthcare utilization in the old‐old population studied. Healthcare utilization was found to be associated primarily with health and functional status.CONCLUSION:In a system of free and equal access to healthcare services, the demand for health services by a population with high levels of chronic disease and disability is driven primarily by health needs, rather than by extraneous factors such as income and education. The study indicates that equity in the provision of health services is attainable. Policy makers should provide for actual need, remove artificial barriers, and prepare accurate estimates of future needs.