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1.
J Environ Manage ; 366: 121732, 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-38981262

ABSTRACT

Trees in cities perform important environmental functions: they produce oxygen, filter pollutants, provide habitat for wildlife, mitigate stormwater runoff, and reduce the effects of climate change, especially in terms of lowering temperatures and converting carbon dioxide from the atmosphere into stored carbon. Generally, to increase the environmental benefits of urban forests, the number of trees is increased, directly influencing the canopy coverage. However, little is known about potential of modifying the species composition of urban tree communities in order to increase ecological benefits. Planting and managing trees to increase canopy is particularly challenging in city centres, where the dense, often historic infrastructure of buildings and roads do not allow for a significant increase in greenspace. Estimations of canopy cover obtained through i-Tree Canopy analysis unveiled significant potential to increase canopy cover in historical urban areas in Polish cities from 15-34% to 31-51%. This study models the ecological benefits of urban forests in Polish cities, focusing on how different species compositions can enhance environmental functions such as carbon sequestration and pollution filtration. Two main scenarios were analyzed: one involving the addition of trees based on the most common species currently planted ("standard option" SO), and another incorporating changes to the species composition to enhance ecological benefits ("city specific option" SCO). Acer platanoides (14.5%) and Tilia cordata (11.45%) were the most frequently species of Polish cities. Betula pendula, Quercus robur, Robinia pseudoacacia, Fraxinus excelsior, Acer pseudoplatanus, Aesculus hippocastanum and Acer campestre were also common species in urban forest communities (up to 5%). The diverse range of tree species in Polish cities contributes significantly to the overall carbon sequestration potential. The results suggest that modifying species composition could significantly increase carbon sequestration rates by 47.8%-114% annually, with the city specific option (SCO) being the most effective in enhancing carbon sequestration potential. This highlights the importance of strategic species selection in urban forestry practices to maximize environmental benefits and mitigate climate change effects.

2.
Environ Manage ; 60(6): 1042-1061, 2017 12.
Article in English | MEDLINE | ID: mdl-28905095

ABSTRACT

Many municipalities are setting ambitious tree canopy cover goals to increase the extent of their urban forests. A historical perspective on urban forest development can help cities strategize how to establish and achieve appropriate tree cover targets. To understand how long-term urban forest change occurs, we examined the history of trees on an urban college campus: the University of Pennsylvania in Philadelphia, PA. Using a mixed methods approach, including qualitative assessments of archival records (1870-2017), complemented by quantitative analysis of tree cover from aerial imagery (1970-2012), our analysis revealed drastic canopy cover increase in the late 20th and early 21st centuries along with the principle mechanisms of that change. We organized the historical narrative into periods reflecting campus planting actions and management approaches; these periods are also connected to broader urban greening and city planning movements, such as City Beautiful and urban sustainability. University faculty in botany, landscape architecture, and urban design contributed to the design of campus green spaces, developed comprehensive landscape plans, and advocated for campus trees. A 1977 Landscape Development Plan was particularly influential, setting forth design principles and planting recommendations that enabled the dramatic canopy cover gains we observed, and continue to guide landscape management today. Our results indicate that increasing urban tree cover requires generational time scales and systematic management coupled with a clear urban design vision and long-term commitments. With the campus as a microcosm of broader trends in urban forest development, we conclude with a discussion of implications for municipal tree cover planning.


Subject(s)
City Planning/organization & administration , Environmental Monitoring/methods , Forestry/organization & administration , Forests , Trees/growth & development , Archives , City Planning/history , Environmental Monitoring/history , Forestry/history , History, 19th Century , History, 20th Century , History, 21st Century , Pennsylvania , Photography , Plant Leaves , Remote Sensing Technology , Urbanization
3.
J Healthc Manag ; 60(6): 442-57, 2015.
Article in English | MEDLINE | ID: mdl-26720989

ABSTRACT

The objective of this report is to present a simplified, activity-based costing approach for hospital emergency departments (EDs) to use with Lean Six Sigma cost-benefit analyses. The cost model complexity is reduced by removing diagnostic and condition-specific costs, thereby revealing the underlying process activities' cost inefficiencies. Examples are provided for evaluating the cost savings from reducing discharge delays and the cost impact of keeping patients in the ED (boarding) after the decision to admit has been made. The process-improvement cost model provides a needed tool in selecting, prioritizing, and validating Lean process-improvement projects in the ED and other areas of patient care that involve multiple dissimilar diagnoses.


Subject(s)
Costs and Cost Analysis , Emergency Service, Hospital/economics , Emergency Service, Hospital/standards , Models, Economic , Quality Improvement/economics , Total Quality Management/economics
4.
Environ Pollut ; 193: 119-129, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25016465

ABSTRACT

Trees remove air pollution by the interception of particulate matter on plant surfaces and the absorption of gaseous pollutants through the leaf stomata. However, the magnitude and value of the effects of trees and forests on air quality and human health across the United States remains unknown. Computer simulations with local environmental data reveal that trees and forests in the conterminous United States removed 17.4 million tonnes (t) of air pollution in 2010 (range: 9.0-23.2 million t), with human health effects valued at 6.8 billion U.S. dollars (range: $1.5-13.0 billion). This pollution removal equated to an average air quality improvement of less than one percent. Most of the pollution removal occurred in rural areas, while most of the health impacts and values were within urban areas. Health impacts included the avoidance of more than 850 incidences of human mortality and 670,000 incidences of acute respiratory symptoms.


Subject(s)
Air Pollutants/isolation & purification , Particulate Matter/isolation & purification , Trees/metabolism , Air Pollutants/metabolism , Air Pollution/analysis , Environment , Humans , Particulate Matter/metabolism , Public Health , United States
5.
Environ Pollut ; 178: 229-36, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23583943

ABSTRACT

Carbon storage and sequestration by urban trees in the United States was quantified to assess the magnitude and role of urban forests in relation to climate change. Urban tree field data from 28 cities and 6 states were used to determine the average carbon density per unit of tree cover. These data were applied to statewide urban tree cover measurements to determine total urban forest carbon storage and annual sequestration by state and nationally. Urban whole tree carbon storage densities average 7.69 kg C m(-2) of tree cover and sequestration densities average 0.28 kg C m(-2) of tree cover per year. Total tree carbon storage in U.S. urban areas (c. 2005) is estimated at 643 million tonnes ($50.5 billion value; 95% CI = 597 million and 690 million tonnes) and annual sequestration is estimated at 25.6 million tonnes ($2.0 billion value; 95% CI = 23.7 million to 27.4 million tonnes).


Subject(s)
Air Pollutants/analysis , Carbon Sequestration , Carbon/analysis , Cities/statistics & numerical data , Trees/physiology , Air Pollution/statistics & numerical data , Climate Change , Conservation of Natural Resources , Environmental Monitoring , Greenhouse Effect , United States
6.
J Trauma Acute Care Surg ; 73(2 Suppl 1): S103-5, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22847077

ABSTRACT

BACKGROUND: Penetrating injuries of proximal femoral and iliac vessels are a common cause of death on the battlefield. Previous studies have shown that by applying 80 lb to 140 lb of pressure externally over the distal abdominal aorta, flow can be ceased in the common femoral artery (CFA). It has also been demonstrated that in a porcine model, an externally applied pneumatic abdominal aortic tourniquet (AAT) can occlude the aorta and inferior vena cava for 60 minutes without bowel injury or significant potassium elevations.The objectives of this study were (1) determine if AAT use in humans results in flow cessation in the CFA, (2) measure the pressure required to cease flow in the CFA, and (3) measure discomfort associated with application of the AAT. METHODS: Pulse wave Doppler measurements were taken in supine volunteers at the right CFA. The AAT was placed just above the iliac crests over the anterior abdomen. The AAT was inflated using a hand pump with an integrated manometer. Measurements were taken every 30 mm Hg. Discomfort was measured using a 10-point pain scale. RESULTS: In all subjects, flow was reduced in the CFA. Flow ceased in seven of nine subjects at a median pressure of 180 mm Hg (150-230 mm Hg). Median discomfort at ceasing of flow was 7 (3-10), returning to 0 after device removal. CONCLUSION: The AAT device was effective at reducing flow in the CFA and ceased flow in most of the subjects. Application of the device was associated with discomfort varying from moderate to severe and resolving with device removal.


Subject(s)
Aorta, Abdominal , Femoral Artery/injuries , Tourniquets , Adult , Aorta, Abdominal/diagnostic imaging , Aorta, Abdominal/physiology , Femoral Artery/physiology , Hemorrhage/therapy , Humans , Iliac Artery/injuries , Iliac Artery/physiology , Male , Regional Blood Flow , Ultrasonography
7.
Prehosp Emerg Care ; 15(4): 477-82, 2011.
Article in English | MEDLINE | ID: mdl-21870945

ABSTRACT

BACKGROUND: Uncontrolled hemorrhage remains the primary cause of preventable battlefield mortality and a significant cause of domestic civilian mortality. Rapid hemorrhage control is crucial for survival. ChitoGauze and Combat Gauze are commercially available products marketed for rapid hemorrhage control. These products were selected because they are packable gauze that work via differing mechanisms of action (tissue adhesion versus procoagulant). OBJECTIVE: To compare the effectiveness of ChitoGauze and Combat Gauze in controlling arterial hemorrhage in a swine model. METHODS: Fourteen swine were studied. Following inguinal dissection and after achieving minimum hemodynamic parameters (mean arterial pressure [MAP] ≥ 70 mmHg), a femoral arterial injury was created using a 6-mm vascular punch. Free bleeding was allowed for 45 seconds, and then the wound was packed alternatively with ChitoGauze or Combat Gauze. Direct pressure was applied to the wound for 2 minutes, followed by a three-hour monitoring period. Resuscitation fluids were administered to maintain an MAP of ≥ 65 mmHg. Time to hemostasis, hemodynamic parameters, total blood loss, and amount of resuscitation fluid were recorded every 15 minutes. Data were analyzed using the Wilcoxon rank sum test. Histologic sections of the vessels were examined using regular and polarized light. RESULTS: No statistically significant differences were found between the groups regarding any measured end point. Data trends, however, favor ChitoGauze over Combat Gauze for time to hemostasis, fluid requirements, and blood loss. There was no evidence of retained foreign material on histologic analysis. CONCLUSION: ChitoGauze and Combat Gauze appear to be equally efficacious in their hemostatic properties, as demonstrated in a porcine hemorrhage model.


Subject(s)
Hemorrhage/therapy , Hemostatic Techniques , Hemostatics/administration & dosage , Animals , Bandages , Disease Models, Animal , Equipment Design , Female , Femoral Artery/injuries , Swine , Treatment Outcome , Wounds, Gunshot/complications
8.
Environ Manage ; 46(3): 378-90, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20676888

ABSTRACT

The 2001 National Land Cover Database (NLCD) provides 30-m resolution estimates of percentage tree canopy and percentage impervious cover for the conterminous United States. Previous estimates that compared NLCD tree canopy and impervious cover estimates with photo-interpreted cover estimates within selected counties and places revealed that NLCD underestimates tree and impervious cover. Based on these previous results, a wall-to-wall comprehensive national analysis was conducted to determine if and how NLCD derived estimates of tree and impervious cover varies from photo-interpreted values across the conterminous United States. Results of this analysis reveal that NLCD significantly underestimates tree cover in 64 of the 65 zones used to create the NCLD cover maps, with a national average underestimation of 9.7% (standard error (SE) = 1.0%) and a maximum underestimation of 28.4% in mapping zone 3. Impervious cover was also underestimated in 44 zones with an average underestimation of 1.4% (SE = 0.4%) and a maximum underestimation of 5.7% in mapping zone 56. Understanding the degree of underestimation by mapping zone can lead to better estimates of tree and impervious cover and a better understanding of the potential limitations associated with NLCD cover estimates.


Subject(s)
Databases, Factual , Ecosystem , Trees , Human Activities , Spacecraft , United States
9.
Ann N Y Acad Sci ; 1185: 1-10, 2010 Jan.
Article in English | MEDLINE | ID: mdl-20146758

ABSTRACT

The Ecological Economics journal is a primary source for inquiry on ecological economics and sustainability. To explore the scholarly pursuit of ecological economics, we conducted a content analysis of 200 randomly sampled research, survey, and methodological articles published in Ecological Economics during the 15-year period of 1989-2004. Results of the analysis were used to investigate facets of transdisciplinarity within the journal. A robust qualitative approach was used to gather and examine data to identify themes representing substantive content found within the span of sampled journal papers. The extent to which each theme was represented was counted as well as additional data, such as author discipline, year published, etc. Four main categories were revealed: (1) foundations (self-reflexive themes stemming from direct discussions about ecological economics); (2) human systems, represented by the themes of values, social indicators of well-being, intergenerational distribution, and equity; (3) biophysical systems, including themes, such as carrying capacity and scarcity, energy, and resource use, relating directly to the biophysical aspects of systems; and (4) policy and management encompassing themes of development, growth, trade, accounting, and valuation, as well as institutional structures and management. The results provide empirical evidence for discussing the future direction of ecological economic efforts.


Subject(s)
Ecology/economics , Periodicals as Topic/standards , Biophysics/methods , Humans , Models, Theoretical , Periodicals as Topic/classification , Periodicals as Topic/statistics & numerical data , Publishing/organization & administration , Publishing/standards , Publishing/trends , Thermodynamics , United States
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