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1.
J Herpetol ; 55(3)2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34937953

RESUMO

Larval amphibians are important components of ephemeral wetland ecosystems, where they are abundant and perform important ecological functions. Larval pond-breeding salamanders (genus Ambystoma) are the primary vertebrate predators in fishless, ephemeral wetland systems, where they consume large amounts of aquatic invertebrate prey. However, the mechanisms in which larval salamanders affect aquatic communities are poorly understood. We compared stomach contents of larval pond-breeding salamanders from two regions in the midwestern United States to assess their diets for evidence of prey selection. We found larval salamanders exhibited selective predation for certain taxa and functional feeding groups. Our results provide a possible mechanism in which larval pond-breeding salamanders affect aquatic invertebrate communities and shape ephemeral wetland ecosystem processes.

2.
J Clean Prod ; 2892021 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-33746371

RESUMO

Green infrastructure (GI) is widely recognized for reducing risk of flooding, improving water quality, and harvesting stormwater for potential future use. GI can be an important part of a strategy used in urban planning to enhance sustainable development and urban resilience. However, existing literature lacks a comprehensive assessment framework to evaluate GI performance in terms of promoting ecosystem functions and services for social-ecological system resilience. We propose a robust indicator set consisting of quantitative and qualitative measurements for a scenario-based planning support system to assess the capacity of urban resilience. Green Infrastructure in Urban Resilience Planning Support System (GIUR-PSS) supports decision-making for GI planning through scenario comparisons with the urban resilience capacity index. To demonstrate GIUR-PSS, we developed five scenarios for the Congress Run sub-watershed (Mill Creek watershed, Ohio, USA) to test common types of GI (rain barrels, rain gardens, detention basins, porous pavement, and open space). Results show the open space scenario achieves the overall highest performance (GI Urban Resilience Index = 4.27/5). To implement the open space scenario in our urban demonstration site, suitable vacant lots could be converted to greenspace (e.g., forest, detention basins, and low-impact recreation areas). GIUR-PSS is easy to replicate, customize, and apply to cities of different sizes to assess environmental, economic, and social benefits provided by different types of GI installations.

3.
Urban Water J ; 19(3): 314-323, 2021 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-35573082

RESUMO

Urban greenspace and green infrastructure are often cited for their many ecosystem services and benefits including stormwater management. However, the localized nature and limited range of effects of these benefits and the type of greenspace and green infrastructure, make planning and placement critical components to selecting for and maximizing desired benefits. Here, the authors test a framework to demonstrate a practical approach to simultaneously manage excess stormwater and maximize distribution of ecosystem services to underserved areas using spatial analysis. St. Louis was subdivided using census block polygons and polygons identified have combined sewer systems with high aggregate annual discharge. Additionally, indicators representing social, economic, and environmental characteristics, which have demonstrated effects from greenspace, were mapped to identify spatial distribution and overlap. The analysis identified one polygon that could promote multiple desired ecosystem services, while reducing annual discharge into combined sewers, and provide these services to an underserved demographic.

4.
Urban Ecosyst ; 22(6): 1139-1148, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31844388

RESUMO

Managing stormwater and wastewater has been a priority for cities for millennia, but has become increasingly complicated as urban areas grow and develop. Since the mid-1800s, cites often relied on an integrated system of underground pipes, pumps, and other built infrastructure (termed gray infrastructure) to convey stormwater away from developed areas. Unfortunately, this gray infrastructure is aging and often exceeds its designed capacity. In an effort to alleviate issues related to excess stormwater, many urban areas across the United States are interested in using green infrastructure as a stopgap or supplement to inadequate gray infrastructure. Green infrastructure and other greenspace promote interception and/or infiltration of stormwater by using the natural hydrologic properties of soil and vegetation. Furthermore, there are numerous ancillary benefits, in addition to stormwater benefits, that make the use of greenspace desirable. Collectively, these ecosystem services can benefit multiple aspects of a community by providing benefits in a targeted manner. In this paper, we present a framework for balancing stormwater management against ancillary benefits of urban greenspace. The framework is structured around the Millennium Ecosystem Assessment ecosystem service categories: provisioning, cultural, regulatory, and supporting services. The purpose is to help communities better manage their systems by 1) allowing stakeholders to prioritize and address their needs and concerns within a community, and 2) maximize the ecosystem service benefits received from urban greenspace.

5.
Environ Sci Technol ; 53(17): 10070-10081, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31432661

RESUMO

Increasing global reliance on stormwater control measures to reduce discharge to surface water, increase groundwater recharge, and minimize contaminant delivery to receiving waterbodies necessitates improved understanding of stormwater-contaminant profiles. A multiagency study of organic and inorganic chemicals in urban stormwater from 50 runoff events at 21 sites across the United States demonstrated that stormwater transports substantial mixtures of polycyclic aromatic hydrocarbons, bioactive contaminants (pesticides and pharmaceuticals), and other organic chemicals known or suspected to pose environmental health concern. Numerous organic-chemical detections per site (median number of chemicals detected = 73), individual concentrations exceeding 10 000 ng/L, and cumulative concentrations up to 263 000 ng/L suggested concern for potential environmental effects during runoff events. Organic concentrations, loads, and yields were positively correlated with impervious surfaces and highly developed urban catchments. Episodic storm-event organic concentrations and loads were comparable to and often exceeded those of daily wastewater plant discharges. Inorganic chemical concentrations were generally dilute in concentration and did not exceed chronic aquatic life criteria. Methylmercury was measured in 90% of samples with concentrations that ranged from 0.05 to 1.0 ng/L.


Assuntos
Água Subterrânea , Praguicidas , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Monitoramento Ambiental , Chuva , Estados Unidos
6.
Sci Total Environ ; 689: 1149-1159, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31466155

RESUMO

Green infrastructure (GI) has been recommended widely to reduce runoff from the built environment. However, reliance on public land for GI implementation could cause a heavy financial burden on local governments. Although economic incentives and market-based mechanisms may encourage public participation in managing stormwater by installing GI on private parcels, a runoff trading market has not been fully developed in practice. To establish a market, in part, requires a watershed-based planning framework and fully informed parcel owners in regard to tradable credits, costs, and benefits. We propose a scenario-based Stormwater Management Planning Support System for Trading Runoff Abatement Credits (SMPSS-TRAC) to facilitate the calculation and allocation of stormwater runoff abatement credits in order to assist the decision-making of GI investment. We apply SMPSS-TRAC to a watershed located in Hamilton County, Ohio, USA and develop five scenarios representing increasing use of GI. We test the scenarios under a 5-year rainfall intensity and set a cap of runoff for each scenario at a level that is equal to the runoff from an undeveloped status (1.03-inch runoff depth for the watershed). With the proposed SMPSS-TRAC, the watershed authority could encourage all parcel owners to install suitable GI or purchase credits from the market. When detention basins are needed to meet a stated goal, the watershed authority would build them on vacant lots and share costs with all parcels within the same sub-catchment. The last scenario with four types of GI installed, shows that the watershed reaches market equilibrium and generates 15,358 m3 credit surplus. SMPSS-TRAC has the potential for including multiple stakeholders' preferences and concerns in searching for preferable scenarios.

7.
J Environ Manage ; 236: 571-580, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30771676

RESUMO

Using combined sewer systems to handle excess stormwater runoff is common in older urban areas. Combined sewer overflow (CSO) events occur when hydraulic capacity is exceeded, and untreated wastewater discharges to surface waters. As urban population density increases, and more demand is placed on infrastructure, CSO events happen more often and cause serious environmental problems and public-health risks. Recently, green infrastructure (GI) has been integrated with existing gray infrastructure (GrayI) to reduce CSO events. However, there lacks a goal-oriented planning framework for eliminating CSOs at a watershed/sewershed scale. Moreover, existing stormwater simulations based on catchments or other geographic units, do not consider spatial variation within the unit, such as distribution, attribution, ownership, and management of GI. We propose a scenario-based Stormwater Management Planning Support System for CSOs (SMPSS-CSO) to provide a platform for reducing CSO events by coordinating parcel-based installations of GI. We applied the SMPSS-CSO to a sewershed with a single CSO location in Cincinnati, Ohio and developed four scenarios representing increased use of GI (rain barrels, green roofs, porous pavements, and detention basin) based on its cost, difficulty of installation, and property ownership. Runoff quantity, time of concentration, and peak flow rate were simulated using the curve number method. Our analysis shows a 41% reduction in stormwater runoff is necessary to eliminate CSO events for a two-year rainfall, required 97.25% of private and 27.59% of public parcels to install GI. GI alone cannot eliminate CSO events in this sewershed and must be incorporated with additional GrayI (e.g., storage tanks, pipes). The SMPSS-CSO has the potential for including multiple stakeholders' preferences and concerns in the searching for preferable scenarios.


Assuntos
Chuva , Águas Residuárias , Ohio , Porosidade , Esgotos
8.
Cities Environ ; 11(1): 1-15, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30275925

RESUMO

As cities are largely private systems, recent investigations have assessed the provision of ecosystem services from the private realm. However, these assessments are largely based on the concept of ownership and fail to capture the complexity of service provision mediated by interactions between people and ecological structures. In fact, people interact with ecological structures in their role of land tenants and stewards, further modulating the provision of ecosystem services. We devise a theoretical framework based on the concepts of ownership, tenancy, and stewardship, in which people, as mediators of ecosystem services, regulate the provision of services throughout the private-social-public domain. We survey relevant literature describing these dimensions and propose a comprehensive framework focused on the private-social-public domain. Our framework can advance ecosystem service research and enhance the provision of ecosystems services. The inclusion of people's individual, social and public roles in the mediation of ecosystem services could improve how benefits are planned for, prioritized, and optimized across cities.

9.
Sci Total Environ ; 639: 1164-1174, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-29929285

RESUMO

The extent of urban ecological homogenization depends on how humans build, inhabit, and manage cities. Morphological and socio-economic facets of neighborhoods can drive the homogenization of urban forest cover, thus affecting ecological and hydrological processes, and ecosystem services. Recent evidence, however, suggests that the same biophysical drivers differentiating composition and structure of natural forests can further counteract the homogenization of urban forests. We hypothesize that climate can differentiate forest structure across residential macrosystems at regional-to-continental spatial scales. To test this hypothesis, forest structure (tree and shrub cover and volume) was measured using LiDAR data and multispectral imagery across a residential macrosystem composed 1.4 million residential parcels contained in 9 cities and 1503 neighborhoods. Cities were selected along an evapotranspiration (ET) gradient in the conterminous United States, ranging from the colder continental climate of Fargo, North Dakota (ET = 464.43 mm) to the hotter subtropical climate of Tallahassee, Florida (ET = 1000.47 mm). The relative effects of climate, urban morphology, and socio-economic variables on residential forest structure were assessed by using generalized linear models. Climate differentiated forest structure of the residential macrosystem as hypothesized. Average forest cover doubled along the ET gradient (0.39-0.78 m2 m-2), whereas average forest volume had a threefold increase (2.50-8.12 m3 m-2). Forest volume across neighborhoods increased exponentially with forest cover. Urban morphology had a greater effect in homogenizing forest structure on residential parcels compared to socio-economics. Climate and urban morphology variables best predicted residential forest structure, whereas socio-economic variables had the lowest predictive power. Results indicate that climate can differentiate forest structure across residential macrosystems and may counteract the homogenizing effects of urban morphology and socio-economic drivers at city-wide scales. This resonates with recent empirical work suggesting the existence of complex multi-scalar mechanisms that regulate ecological homogenization and ecosystem convergence among cities. The study initiates high-resolution assessments of forest structure across entire urban macrosystems and breaks new ground for research on the ecological and hydrological significance of urban vegetation at subcontinental scale.

10.
Sustainability ; 10(3)2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32542114

RESUMO

Many cities are experiencing long-term declines in population and economic activity. As a result, frameworks for urban sustainability need to address the unique challenges and opportunities of such shrinking cities. Shrinking, particularly in the U.S., has led to extensive vacant land. The abundance of vacant land reflects a loss of traditional urban amenities, economic opportunity, neighbors, businesses, and even basic city services and often occurs in neighborhoods with socially and economically vulnerable or underserved populations. However, vacant land also provides opportunities, including the space to invest in green infrastructure that can provide ecosystem services and support urban sustainability. Achieving desirable amenities that provide ecosystem services from vacant land is the central tenet of a recent urban sustainability framework termed ecology for the shrinking city. An agroecological approach could operationalize ecology for the shrinking city to both manage vacancy and address ecosystem service goals. Developing an agroecology in shrinking cities not only secures provisioning services that use an active and participatory approach of vacant land management but also transforms and enhances regulating and supporting services. The human and cultural dimensions of agroecology create the potential for social-ecological innovations that can support sustainable transformations in shrinking cities. Overall, the strength of agroecological principles guiding a green infrastructure strategy stems from its explicit focus on how individuals and communities can shape their environment at multiple scales to produce outcomes that reflect their social and cultural context. Specifically, the shaping of the environment provides a pathway for communities to build agency and manage for resilience in urban social-ecological systems. Agroecology for the shrinking city can support desirable transformations, but to be meaningful, we recognize that it must be part of a greater strategy that addresses larger systemic issues facing shrinking cities and their residents.

11.
Sci Total Environ ; 612: 940-949, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-28886546

RESUMO

The spatial arrangement of urban vegetation depends on urban morphology and socio-economic settings. Urban vegetation changes over time because of human management. Urban trees are removed due to hazard prevention or aesthetic preferences. Previous research attributed tree loss to decreases in canopy cover. However, this provides little information about location and structural characteristics of trees lost, as well as environmental and social factors affecting tree loss dynamics. This is particularly relevant in residential landscapes where access to residential parcels for field surveys is limited. We tested whether multi-temporal airborne LiDAR and multi-spectral imagery collected at a 5-year interval can be used to investigate urban tree loss dynamics across residential landscapes in Denver, CO and Milwaukee, WI, covering 400,705 residential parcels in 444 census tracts. Position and stem height of trees lost were extracted from canopy height models calculated as the difference between final (year 5) and initial (year 0) vegetation height derived from LiDAR. Multivariate regression models were used to predict number and height of tree stems lost in residential parcels in each census tract based on urban morphological and socio-economic variables. A total of 28,427 stems were lost from residential parcels in Denver and Milwaukee over 5years. Overall, 7% of residential parcels lost one stem, averaging 90.87 stems per km2. Average stem height was 10.16m, though trees lost in Denver were taller compared to Milwaukee. The number of stems lost was higher in neighborhoods with higher canopy cover and developed before the 1970s. However, socio-economic characteristics had little effect on tree loss dynamics. The study provides a simple method for measuring urban tree loss dynamics within and across entire cities, and represents a further step toward high resolution assessments of the three-dimensional change of urban vegetation at large spatial scales.


Assuntos
Cidades , Características de Residência , Árvores , Colorado , Monitoramento Ambiental , Humanos , Wisconsin
12.
Ecology ; 98(5): 1475, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28263380

RESUMO

Animals can be important in modulating ecosystem-level nutrient cycling, although their importance varies greatly among species and ecosystems. Nutrient cycling rates of individual animals represent valuable data for testing the predictions of important frameworks such as the Metabolic Theory of Ecology (MTE) and ecological stoichiometry (ES). They also represent an important set of functional traits that may reflect both environmental and phylogenetic influences. Over the past two decades, studies of animal-mediated nutrient cycling have increased dramatically, especially in aquatic ecosystems. Here we present a global compilation of aquatic animal nutrient excretion rates. The dataset includes 10,534 observations from freshwater and marine animals of N and/or P excretion rates. These observations represent 491 species, including most aquatic phyla. Coverage varies greatly among phyla and other taxonomic levels. The dataset includes information on animal body size, ambient temperature, taxonomic affiliations, and animal body N:P. This data set was used to test predictions of MTE and ES, as described in Vanni and McIntyre (2016; Ecology DOI: 10.1002/ecy.1582).


Assuntos
Organismos Aquáticos/metabolismo , Nitrogênio/metabolismo , Fósforo/metabolismo , Animais , Ecossistema , Água Doce , Filogenia
13.
Landsc Urban Plan ; 162: 167-177, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30220756

RESUMO

Urban impervious surfaces convert precipitation to stormwater runoff, which causes water quality and quantity problems. While traditional stormwater management has relied on gray infrastructure such as piped conveyances to collect and convey stormwater to wastewater treatment facilities or into surface waters, cities are exploring green infrastructure to manage stormwater at its source. Decentralized green infrastructure leverages the capabilities of soil and vegetation to infiltrate, redistribute, and otherwise store stormwater volume, with the potential to realize ancillary environmental, social, and economic benefits. To date, green infrastructure science and practice have largely focused on infiltration-based technologies that include rain gardens, bioswales, and permeable pavements. However, a narrow focus on infiltration overlooks other losses from the hydrologic cycle, and we propose that arboriculture - the cultivation of trees and other woody plants - deserves additional consideration as a stormwater control measure. Trees interact with the urban hydrologic cycle by intercepting incoming precipitation, removing water from the soil via transpiration, enhancing infiltration, and bolstering the performance of other green infrastructure technologies. However, many of these interactions are inadequately understood, particularly at spatial and temporal scales relevant to stormwater management. As such, the reliable use of trees for stormwater control depends on improved understanding of how and to what extent trees interact with stormwater, and the context-specific consideration of optimal arboricultural practices and institutional frameworks to maximize the stormwater benefits trees can provide.

14.
Ecol Modell ; 355: 64-69, 2017 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-30220776

RESUMO

Measures of biological or species diversity are central to ecology and conservation biology. Although there are several commonly used indices, each has shortcomings and all vary in the relative emphasis they place on the number of species and their relative abundance. We propose utilizing Fisher Information, not as a replacement for existing indices, but as a supplement to other indices because it is sensitive to community structure. We demonstrate how Shannon's and Simpson's diversity indices quantify the diversity of two different systems and how Fisher Information can enhance the analyses by comparing, as example, body size, and phylogenetic diversity of the different communities. Fisher Information is sensitive to the order in which species are entered into the analysis, and therefore, it can detect differences in community structure. Thus, the Fisher Information index can be useful in helping understand and analyze biodiversity of ecosystems and in comparing ecological communities.

15.
J Environ Manage ; 183(Pt 2): 399-407, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27377866

RESUMO

In a world of increasing interconnections in global trade as well as rapid change in climate and land cover, the accelerating introduction and spread of invasive species is a critical concern due to associated negative social and ecological impacts, both real and perceived. Much of the societal response to invasive species to date has been associated with negative economic consequences of invasions. This response has shaped a war-like approach to addressing invasions, one with an agenda of eradications and intense ecological restoration efforts towards prior or more desirable ecological regimes. This trajectory often ignores the concept of ecological resilience and associated approaches of resilience-based governance. We argue that the relationship between ecological resilience and invasive species has been understudied to the detriment of attempts to govern invasions, and that most management actions fail, primarily because they do not incorporate adaptive, learning-based approaches. Invasive species can decrease resilience by reducing the biodiversity that underpins ecological functions and processes, making ecosystems more prone to regime shifts. However, invasions do not always result in a shift to an alternative regime; invasions can also increase resilience by introducing novelty, replacing lost ecological functions or adding redundancy that strengthens already existing structures and processes in an ecosystem. This paper examines the potential impacts of species invasions on the resilience of ecosystems and suggests that resilience-based approaches can inform policy by linking the governance of biological invasions to the negotiation of tradeoffs between ecosystem services.


Assuntos
Conservação dos Recursos Naturais/métodos , Ecossistema , Espécies Introduzidas , Animais , Biodiversidade , Ecologia , Política Ambiental
16.
Bioscience ; 66(11): 965-973, 2016 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-32606477

RESUMO

This article brings together the concepts of shrinking cities-the hundreds of cities worldwide experiencing long-term population loss-and ecology for the city. Ecology for the city is the application of a social-ecological understanding to shaping urban form and function along sustainable trajectories. Ecology for the shrinking city therefore acknowledges that urban transformations to sustainable trajectories may be quite different in shrinking cities as compared with growing cities. Shrinking cities are well poised for transformations, because shrinking is perceived as a crisis and can mobilize the social capacity to change. Ecology is particularly well suited to contribute solutions because of the extent of vacant land in shrinking cities that can be leveraged for ecosystem-services provisioning. A crucial role of an ecology for the shrinking city is identifying innovative pathways that create locally desired amenities that provide ecosystem services and contribute to urban sustainability at multiple scales.

17.
Integr Zool ; 9(5): 613-22, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25236804

RESUMO

Ecological stoichiometry provides a framework to investigate an organism's relationship to nutrient cycles. An organism's stoichiometry is thought to constrain its contribution to nutrient cycles (recycling or storage), and to limit its growth and reproduction. Factors that influence the stoichiometry of a consumer are largely unstudied, but what is known is that consumer stoichiometry is influenced by the elemental requirements of the consumer (e.g. for growth, reproduction and cell maintenance) and the availability of elements. We examined whole-body stoichiometry of larval southern two-lined salamanders (Eurycea cirrigera) and described the influence of location, body size, stoichiometry of diet items, and environmental nutrient supply on whole-body stoichiometry. Mean composition of phosphorous was 2.6%, nitrogen was 11.3%, and carbon was 39.6%, which are similar for other aquatic vertebrate taxa. The most significant predictor of whole-body stoichiometry was the site where the samples were collected, which was significant for each nutrient and nutrient ratio. Body size and stoichiometry of diet items were also predictors of Eurycea cirrigera stoichiometry. Our study suggests that spatial differences in environmental nutrient supply have a stronger influence on consumer whole-body stoichiometry among similar-sized larvae compared to life history traits, such as body size or diet.


Assuntos
Tamanho Corporal , Dieta/veterinária , Meio Ambiente , Urodelos/fisiologia , Animais , Carbono/análise , Água Doce/química , Larva , Nitrogênio/análise , Ohio , Fósforo/análise
18.
PLoS One ; 9(1): e85011, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24465468

RESUMO

Decentralized stormwater management approaches (e.g., biofiltration swales, pervious pavement, green roofs, rain gardens) that capture, detain, infiltrate, and filter runoff are now commonly used to minimize the impacts of stormwater runoff from impervious surfaces on aquatic ecosystems. However, there is little research on the effectiveness of retrofit, parcel-scale stormwater management practices for improving downstream aquatic ecosystem health. A reverse auction was used to encourage homeowners to mitigate stormwater on their property within the suburban, 1.8 km(2) Shepherd Creek catchment in Cincinnati, Ohio (USA). In 2007-2008, 165 rain barrels and 81 rain gardens were installed on 30% of the properties in four experimental (treatment) subcatchments, and two additional subcatchments were maintained as controls. At the base of the subcatchments, we sampled monthly baseflow water quality, and seasonal (5×/year) physical habitat, periphyton assemblages, and macroinvertebrate assemblages in the streams for the three years before and after treatment implementation. Given the minor reductions in directly connected impervious area from the rain barrel installations (11.6% to 10.4% in the most impaired subcatchment) and high total impervious levels (13.1% to 19.9% in experimental subcatchments), we expected minor or no responses of water quality and biota to stormwater management. There were trends of increased conductivity, iron, and sulfate for control sites, but no such contemporaneous trends for experimental sites. The minor effects of treatment on streamflow volume and water quality did not translate into changes in biotic health, and the few periphyton and macroinvertebrate responses could be explained by factors not associated with the treatment (e.g., vegetation clearing, drought conditions). Improvement of overall stream health is unlikely without additional treatment of major impervious surfaces (including roads, apartment buildings, and parking lots). Further research is needed to define the minimum effect threshold and restoration trajectories for retrofitting catchments to improve the health of stream ecosystems.


Assuntos
Biota , Conservação dos Recursos Naturais , Chuva , Características de Residência , Rios , População Suburbana , Qualidade da Água , Análise de Variância , Animais , Biomassa , Filtração , Geografia , Invertebrados/fisiologia , Ohio , Movimentos da Água
19.
J Environ Manage ; 111: 272-8, 2012 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-22560056

RESUMO

This paper introduces a collection of four articles describing the San Luis Basin Sustainability Metrics Project. The Project developed a methodology for evaluating regional sustainability. This introduction provides the necessary background information for the project, description of the region, overview of the methods, and summary of the results. Although there are a multitude of scientifically based sustainability metrics, many are data intensive, difficult to calculate, and fail to capture all aspects of a system. We wanted to see if we could develop an approach that decision-makers could use to understand if their system was moving toward or away from sustainability. The goal was to produce a scientifically defensible, but straightforward and inexpensive methodology to measure and monitor environmental quality within a regional system. We initiated an interdisciplinary pilot project in the San Luis Basin, south-central Colorado, to test the methodology. The objectives were: 1) determine the applicability of using existing datasets to estimate metrics of sustainability at a regional scale; 2) calculate metrics through time from 1980 to 2005; and 3) compare and contrast the results to determine if the system was moving toward or away from sustainability. The sustainability metrics, chosen to represent major components of the system, were: 1) Ecological Footprint to capture the impact and human burden on the system; 2) Green Net Regional Product to represent economic welfare; 3) Emergy to capture the quality-normalized flow of energy through the system; and 4) Fisher information to capture the overall dynamic order and to look for possible regime changes. The methodology, data, and results of each metric are presented in the remaining four papers of the special collection. Based on the results of each metric and our criteria for understanding the sustainability trends, we find that the San Luis Basin is moving away from sustainability. Although we understand there are strengths and limitations of the methodology, we argue that each metric identifies changes to major components of the system.


Assuntos
Conservação dos Recursos Naturais/métodos , Monitoramento Ambiental/métodos , Pegada de Carbono , Colorado , Tomada de Decisões , Meio Ambiente , Projetos Piloto , Fatores de Tempo
20.
J Environ Manage ; 111: 279-86, 2012 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-22033065

RESUMO

We calculated an Ecological Footprint Analysis (EFA) at a regional scale. EFA captures the human impact on the environmental system by identifying the amount of biologically productive land necessary to support a person's level of consumption and waste generation. EFA is a commonly used metric of sustainability because it is easy to conceptualize and the calculation is relatively straightforward. Utilizing free, readily available data, we calculated an EFA for a region in southern Colorado. Gathering existing data at a regional scale is difficult because data are often collected at national or state levels. The lack of data is further confounded by the fact that data are often collected at intervals greater than one year. Variables that were missing data for certain years were estimated using linear interpolation. Data not available by county were scaled to the region from state or national level data. Thirty-five variables from 1980 to 2005 (26 years) were collected and used to calculate a time-dependent EFA and the resulting trend was visually examined. The available biocapacity in the region did not decrease during the period, but per capita biocapacity decreased due to population growth. Per capita biocapacity was at a period high of nearly 41 ha per person (ha/ca) in 1980 and steadily decreased to a low around 31 ha/ca in 2005. Ecological footprint remained constant over the 26-year period, varying from a low of 5.1 ha/ca in 1997 to a high of 5.5 ha/ca in 1985. A steady ecological footprint combined with a decreasing per capita biocapacity, implies the ecological reserve is decreasing and, thus, the region is moving away from sustainability. Although per capita consumption did not increase substantially during the 26 years, more people are drawing on a fixed quantity of resources. Our methodology is a simplified approach to EFA and does not follow standards that are currently being established. Adhering to the suggested standards would require obtaining data sets that consist entirely of national data. The national level data are replaced with data specific to the geographic area under examination when they are available. Although national data may represent the sub-national region under study, that substitution requires further investigation, especially in large, geographically and culturally varied nations such as the US. Nevertheless, this simplified methodology provides enough detail that stakeholders can identify areas of the system on which to focus attention to improve sustainability of the system.


Assuntos
Conservação dos Recursos Naturais , Monitoramento Ambiental/métodos , Pegada de Carbono , Colorado , Meio Ambiente , Fatores de Tempo
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