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1.
Development of a New Approach to Cumulative Effects Assessment: A Northern River Ecosystem Example 总被引:2,自引:0,他引:2
Dubé M Johnson B Dunn G Culp J Cash K Munkittrick K Wong I Hedley K Booty W Lam D Resler O Storey A 《Environmental monitoring and assessment》2006,113(1-3):87-115
If sustainable development of Canadian waters is to be achieved, a realistic and manageable framework is required for assessing cumulative effects. The objective of this paper is to describe an approach for aquatic cumulative effects assessment that was developed under the Northern Rivers Ecosystem Initiative. The approach is based on a review of existing monitoring practices in Canada and the presence of existing thresholds for aquatic ecosystem health assessments. It suggests that a sustainable framework is possible for cumulative effects assessment of Canadian waters that would result in integration of national indicators of aquatic health, integration of national initiatives (e.g., water quality index, environmental effects monitoring), and provide an avenue where long-term monitoring programs could be integrated with baseline and follow-up monitoring conducted under the environmental assessment process. 相似文献
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Probability-based designs reduce bias and allow inference of results to the pool of sites from which they were chosen. We developed and tested probability-based designs for monitoring marine rocky intertidal assemblages at Glacier Bay National Park and Preserve (GLBA), Alaska. A multilevel design was used that varied in scale and inference. The levels included aerial surveys, extensive sampling of 25 sites, and more intensive sampling of 6 sites. Aerial surveys of a subset of intertidal habitat indicated that the original target habitat of bedrock-dominated sites with slope ≤30° was rare. This unexpected finding illustrated one value of probability-based surveys and led to a shift in the target habitat type to include steeper, more mixed rocky habitat. Subsequently, we evaluated the statistical power of different sampling methods and sampling strategies to detect changes in the abundances of the predominant sessile intertidal taxa: barnacles Balanomorpha, the mussel Mytilus trossulus, and the rockweed Fucus distichus subsp. evanescens. There was greatest power to detect trends in Mytilus and lesser power for barnacles and Fucus. Because of its greater power, the extensive, coarse-grained sampling scheme was adopted in subsequent years over the intensive, fine-grained scheme. The sampling attributes that had the largest effects on power included sampling of “vertical” line transects (vs. horizontal line transects or quadrats) and increasing the number of sites. We also evaluated the power of several management-set parameters. Given equal sampling effort, sampling more sites fewer times had greater power. The information gained through intertidal monitoring is likely to be useful in assessing changes due to climate, including ocean acidification; invasive species; trampling effects; and oil spills. 相似文献
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Robert K. Hall David Guiliano Sherman Swanson Michael J. Philbin John Lin Joan L. Aron Robin J. Schafer Daniel T. Heggem 《Environmental monitoring and assessment》2014,186(4):2413-2433
Prioritizing total maximum daily load (TMDL) development starts by considering the scope and severity of water pollution and risks to public health and aquatic life. Methodology using quantitative assessments of in-stream water quality is appropriate and effective for point source (PS) dominated discharge, but less so in watersheds with mostly nonpoint source (NPS) related impairments. For NPSs, prioritization in TMDL development and implementation of associated best management practices should focus on restoration of ecosystem physical functions, including how restoration effectiveness depends on design, maintenance and placement within the watershed. To refine the approach to TMDL development, regulators and stakeholders must first ask if the watershed, or ecosystem, is at risk of losing riparian or other ecologically based physical attributes and processes. If so, the next step is an assessment of the spatial arrangement of functionality with a focus on the at-risk areas that could be lost, or could, with some help, regain functions. Evaluating stream and wetland riparian function has advantages over the traditional means of water quality and biological assessments for NPS TMDL development. Understanding how an ecosystem functions enables stakeholders and regulators to determine the severity of problem(s), identify source(s) of impairment, and predict and avoid a decline in water quality. The Upper Reese River, Nevada, provides an example of water quality impairment caused by NPS pollution. In this river basin, stream and wetland riparian proper functioning condition (PFC) protocol, water quality data, and remote sensing imagery were used to identify sediment sources, transport, distribution, and its impact on water quality and aquatic resources. This study found that assessments of ecological function could be used to generate leading (early) indicators of water quality degradation for targeting pollution control measures, while traditional in-stream water quality monitoring lagged in response to the deterioration in ecological functions. 相似文献
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Juliana Jiménez-Valencia Philip R. Kaufmann Ana Sattamini Riccardo Mugnai Darcilio Fernandes Baptista 《Environmental monitoring and assessment》2014,186(8):4685-4695
Prompt assessment and management actions are required if we are to reduce the current rapid loss of habitat and biodiversity worldwide. Statistically valid quantification of the biota and habitat condition in water bodies are prerequisites for rigorous assessment of aquatic biodiversity and habitat. We assessed the ecological condition of streams in a southeastern Brazilian basin. We quantified the percentage of stream length in good, fair, and poor ecological condition according to benthic macroinvertebrate assemblage. We assessed the risk of finding degraded ecological condition associated with degraded aquatic riparian physical habitat condition, watershed condition, and water quality. We describe field sampling and implementation issues encountered in our survey and discuss design options to remedy them. Survey sample sites were selected using a spatially balanced, stratified random design, which enabled us to put confidence bounds on the ecological condition estimates derived from the stream survey. The benthic condition index indicated that 62 % of stream length in the basin was in poor ecological condition, and 13 % of stream length was in fair condition. The risk of finding degraded biological condition when the riparian vegetation and forests in upstream catchments were degraded was 2.5 and 4 times higher, compared to streams rated as good for the same stressors. We demonstrated that the GRTS statistical sampling method can be used routinely in Brazilian rain forests and other South American regions with similar conditions. This survey establishes an initial baseline for monitoring the condition and trends of streams in the region. 相似文献
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Carol C. House J. Jeffery Goebel Hans T. Schreuder Paul H. Geissler William R. Williams Anthony R. Olsen 《Environmental monitoring and assessment》1998,51(1-2):451-463
A demonstration project in Oregon examined the feasibility of combining Federal environmental monitoring surveys. An integrated approach should remove duplication of effort and reduce the possibility of providing apparently conflicting information to policy makers and the public. Data collection teams made photo interpretation measurements and on-site soil/vegetation/animal observations at locations that were selected from the Forest Inventory and Analysis (FIA), National Forest System (NFS) Region 6, and National Resource Inventory (NRI) surveys in a six-county area in Northern Oregon. The project demonstrated the feasibility of conducting a combined FIA/NFS/NRI survey and suggests an approach that will preserve the utility of the critical historical information from these surveys. We suggest a framework for estimating the extent of forest and range land that explains FIA/NRI differences and provides a common basis for both surveys. We suggest indicator and protocol criteria that will allow consistent national and regional estimates over all vegetation types, and stress the importance of including measurement repeatability in the design of the combined survey. 相似文献
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R. Brooks M. McKenney-Easterling M. Brinson R. Rheinhardt K. Havens D. O’Brien J. Bishop J. Rubbo B. Armstrong J. Hite 《Environmental monitoring and assessment》2009,150(1-4):101-117
As part of a regional study by the Atlantic Slope Consortium (ASC) to develop ecological and socioeconomic indicators of aquatic ecosystem condition, we developed and tested a protocol for rapidly assessing condition of the stream, wetland, and riparian components of freshwater aquatic ecosystems. Aspects of hydrology, vegetation, in-stream and wetland characteristics, and on-site stressors were measured in the field. The resulting metrics were used to develop an index of overall condition, termed the Stream–Wetland–Riparian (SWR) Index. Values of this Index were compared to existing biotic indices and chemical measures, and to a Landscape Index created using satellite-based land cover data and a geographic information system (GIS). Comparisons were made at several levels of spatial aggregation and resolution, from site to small watershed. The SWR Index and associated Landscape Indices were shown to correlate highly with biological indicators of stream condition at the site level and for small contributing areas. The landscape patterns prevalent throughout the entire watershed do not necessarily match the patterns found adjacent to the stream network. We suggest a top-down approach that managers can use to sequentially apply these methods, to first prioritize watersheds based on a relative condition measure provided by the Landscape Index, and then assess condition and diagnose stressors of aquatic resources at the subwatershed and site level. 相似文献
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Implementing a statistically valid and practical monitoring design for large-scale stream condition monitoring and assessment programs can be difficult due to factors including the likely existence of a diversity of ecosystem types such as ephemeral streams over the sampling domain; limited resources to undertake detailed monitoring surveys and address knowledge gaps; and operational constraints on effective sampling at monitoring sites. In statistical speak, these issues translate to defining appropriate target populations and sampling units; designing appropriate spatial and temporal sample site selection methods; selection and use of appropriate indicators; and setting effect sizes with limited ecological and statistical information about the indicators of interest. We identify the statistical and operational challenges in designing large-scale stream condition surveys and discuss general approaches for addressing them. The ultimate aim in drawing attention to these challenges is to ensure operational practicality in carrying out future monitoring programs and that the resulting inferences about stream condition are statistically valid and relevant. 相似文献
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利用2014年和2018年鄱阳湖丰〖CD*2〗涨〖CD*2〗枯〖CD*2〗退4个水文时期的监测数据,引入可拓评价法对鄱阳湖水生态系统健康进行评价并探讨指标动态权重的影响。结果表明:鄱阳湖水生态系统健康状态不同水文时期差异显著,退水期最优,枯水期最差,涨水期稍优于丰水期。鄱阳湖水生态系统健康评价指标权重具有动态变化特征,指标权重值会随着指标具体取值的不同而发生变化,即便指标值相同,各指标间关系不同,指标权重也不同,从而影响鄱阳湖水生态系统健康的评价结果。鄱阳湖不同时期生态系统功能和结构差异较大,采用动态的权重对其水生态系统健康评价相对更加合理。 相似文献
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Robert K. Hall Russell L. Watkins Daniel T. Heggem K. Bruce Jones Philip R. Kaufmann Steven B. Moore Sandra J. Gregory 《Environmental monitoring and assessment》2009,159(1-4):63-83
Structural physical habitat attributes include indices of stream size, channel gradient, substrate size, habitat complexity, and riparian vegetation cover and structure. The Environmental Monitoring and Assessment Program (EMAP) is designed to assess the status and trends of ecological resources at different scales. High-resolution remote sensing provides unique capabilities in detecting a variety of features and indicators of environmental health and condition. LIDAR is an airborne scanning laser system that provides data on topography, channel dimensions (width, depth), slope, channel complexity (residual pools, volume, morphometric complexity, hydraulic roughness), riparian vegetation (height and density), dimensions of riparian zone, anthropogenic alterations and disturbances, and channel and riparian interaction. Hyperspectral aerial imagery offers the advantage of high spectral and spatial resolution allowing for the detection and identification of riparian vegetation and natural and anthropogenic features at a resolution not possible with satellite imagery. When combined, or fused, these technologies comprise a powerful geospatial data set for assessing and monitoring lentic and lotic environmental characteristics and condition. 相似文献
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Submerged aquatic vegetation (SAV) is considered an important habitat for juvenile and small forage fish species, but many
long-term recruitment surveys do not effectively monitor fish communities in SAV. To better understand the impact of recent
large increases of SAV on the fish community in tidal freshwater reaches of the Potomac River, we compared traditional seine
sampling from shore with drop ring sampling of SAV beds (primarily Hydrilla) in a shallow water (depths, <1.5 m) embayment,
Gunston Cove. To accomplish this, we developed species-specific catch efficiency values for the seine gear and calculated
area-based density in both shoreline and SAV habitats in late summer of three different years (2007, 2008, and 2009). For
the dominant species (Fundulus diaphanus, Lepomis macrochirus, Etheostoma olmstedi, Morone americana, Lepomis gibbosus, and Fundulus heteroclitus), density was nearly always higher in SAV, but overall, species richness was highest in shoreline habitats sampled with seines.
Although historical monitoring of fish in Gunston Cove (and throughout Chesapeake Bay) is based upon seine sampling (and trawl
sampling in deeper areas), the high densities of fish and larger areal extent of SAV indicated that complementary sampling
of SAV habitats would produce more accurate trends in abundances of common species. Because drop ring samples cover much less
area than seines and may miss rare species, a combination of methods that includes seine sampling is needed for biodiversity
assessment. The resurgence of SAV in tidal freshwater signifies improving water quality, and methods we evaluated here support
improved inferences about population trends and fish community structure as indicators of ecosystem condition. 相似文献
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Simona Ceschin Ilaria Tombolini Silverio Abati Vincenzo Zuccarello 《Environmental monitoring and assessment》2015,187(5):301
River damming leads to strong hydromorphological alterations of the watercourse, consequently affecting river vegetation pattern. A multitemporal and spatial analysis of the dam effect on composition, structure and dynamic of the upstream vegetation was performed on Tiber River at Nazzano-dam (Rome). The main research questions were as follows: How does plant landscape vary over time and along the river? Where does the dam effect on vegetation end? How does naturalistic importance of the vegetation affected by damming change over time? Data collection was performed mapping the vegetation in aerial photos related to the period before (1944), during (1954) and after dam construction (1984, 2000). The plant landscape has significantly changed over time and along the river, particularly as a result of the dam construction (1953). The major vegetation changes have involved riparian forests and macrophytes. Dam effect on vegetation is evident up to 3 km, and gradually decreases along an attenuation zone for about another 3 km. Despite the fact that the damming has caused strong local hydromorphological modification of the river ecosystem transforming it into a sub-lacustrine habitat, it has also led to the formation of wetlands of considerable naturalistic importance. Indeed, in these man-made wetlands, optimal hydrological conditions have been created by favouring both the expansion of pre-existing riparian communities and the rooting of new aquatic communities, albeit typical of lacustrine ecosystems. Some of these plant communities have become an important food resource, refuge or nesting habitats for aquatic fauna, while others fall into category of Natura 2000 habitats. Therefore, river damming seems to have indirectly had a “favourable” effect for habitat conservation and local biodiversity. 相似文献
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基于结构功能指标体系评价法,利用层次分析法构建锦州湾海域生态系统健康评价指标体系,并选择2005—2009年8月生态调查数据对其进行初步的定量评价。结果表明,可以通过海洋化学指标、生态学指标和社会经济学指标三大类33个指标来建立锦州湾生态系统健康评价指标体系;2005—2009年8月锦州湾生态系统的整合健康指数依次分别为1.01、1.90、2.00、1.45和1.10,均低于系统健康指数值2,锦州湾海域生态系统连续5年一直处于亚健康状态,且从目前海域的污染现状来看,这一海域的水质、沉积物和生物体污染均比较严重,要修复其生态功能需要投入巨大的物质和能量。 相似文献
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Smith LM Didonato EM Harwell LC Nestlerode JA Summers JK 《Environmental monitoring and assessment》2007,128(1-3):511-524
Using the approach established by EPA's Environmental Monitoring and Assessment Program (EMAP), a shoreline monitoring survey
was conducted in August and September 1999, encompassing the Florida Panhandle from Perdido Key, Florida to Port St. Joe,
Florida. The objective of this survey was to demonstrate the use of a probabilistic survey for monitoring and estimating the
condition of swimmable beach areas. Thirty stations were sampled using a probabilistic sampling design. Hydrographic data
were collected in addition to samples for water chemistry. Bacterial indicators, enterococci and fecal coliforms, were enumerated
from the water according to the EPA Beaches Environmental Assessment Closure and Health (BEACH) Program and Florida state
guidelines. Additional criteria for site condition included the presence or absence of primary and secondary dunes, anthropogenic
debris and vegetation. Based on EMAP evaluation guidelines and Florida state criteria, a baseline assessment of the condition
of the Gulf of Mexico beach resources surveyed is presented. 相似文献
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Maria C. Dzul Philip M. Dixon Michael C. Quist Stephen J. Dinsmore Michael R. Bower Kevin P. Wilson D. Bailey Gaines 《Environmental monitoring and assessment》2013,185(1):405-414
We used variance components to assess allocation of sampling effort in a hierarchically nested sampling design for ongoing monitoring of early life history stages of the federally endangered Devils Hole pupfish (DHP) (Cyprinodon diabolis). Sampling design for larval DHP included surveys (5 days each spring 2007–2009), events, and plots. Each survey was comprised of three counting events, where DHP larvae on nine plots were counted plot by plot. Statistical analysis of larval abundance included three components: (1) evaluation of power from various sample size combinations, (2) comparison of power in fixed and random plot designs, and (3) assessment of yearly differences in the power of the survey. Results indicated that increasing the sample size at the lowest level of sampling represented the most realistic option to increase the survey’s power, fixed plot designs had greater power than random plot designs, and the power of the larval survey varied by year. This study provides an example of how monitoring efforts may benefit from coupling variance components estimation with power analysis to assess sampling design. 相似文献
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Clarke KD Lewis M Brandle R Ostendorf B 《Environmental monitoring and assessment》2012,184(2):625-635
Rare, small or annual vegetation species are widely known to be imperfectly detected with single site surveys by most conventional
vegetation survey methods. However, the detectability of common, persistent vegetation species is assumed to be high, but
without supporting research. In this study, we evaluate the extent of false-negative errors of perennial vegetation species
in a systematic vegetation survey in arid South Australia. Analysis was limited to the seven most easily detected persistent
vegetation species and controlled for observer skill. By comparison of methodologies, we then predict the magnitude of non-detection
error rates in a second survey. The analysis revealed that all but one highly detectable perennial vegetation species was
imperfectly detected (detection probabilities ranged from 0.22 to 0.83). While focussed in the Australian rangelands, the
implications of this study are far reaching. Inferences drawn from systematic vegetation surveys that fail to identify and
account for non-detection errors should be considered potentially flawed. The identification of this problem in vegetation
surveying is long overdue. By comparison, non-detection has been a widely acknowledged, and dealt with, problem in fauna surveying
for decades. We recommend that, where necessary, vegetation survey methodology adopt the methods developed in fauna surveying
to cope with non-detection errors. 相似文献
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Design of River Water Quality Monitoring Networks: A Case Study 总被引:3,自引:0,他引:3
Mohammad Karamouz Reza Kerachian Masih Akhbari Bahareh Hafez 《Environmental Modeling and Assessment》2009,14(6):705-714
Karoon River, from Gotvand Dam to Persian Gulf with more than 450 km in length and an annual discharge of 11,891 million cubic
meters, is the largest river in Iran. Increasing water withdrawal from and wastewater discharge to the river has endangered
the aquatic life of this important ecosystem. Furthermore, the drinking and in-stream water quality standards have been violated
in many instances. In this paper, a river water quality monitoring network is designed, including determination of sampling
frequencies as well as location of water quality monitoring stations. In this regard, two models are developed. The first
model is a Genetic Algorithm-based optimization model and the second one is a combination of Kriging method and Analytical
Hierarchy Process. The temporal variation of the concentration of water quality variables along Karoon and Dez Rivers are
evaluated and the main water quality indicators are selected. Then, thirty five stations are selected and the application
of Entropy Theory in calculating the sampling frequency is demonstrated. The results show the significant value of the proposed
methodology in the design of monitoring network. 相似文献