共查询到20条相似文献,搜索用时 0 毫秒
1.
Forest Health Monitoring in the United States: First Four Years 总被引:24,自引:0,他引:24
To address the need for more effective methods for evaluating and assessing forest ecosystem health, the USDA-Forest Service and the US Environmental Protection Agency through its Environmental Monitoring and Assessment Program developed the Forest Health Monitoring program. The program was initiated in 1990 and by 1994 was present in the major areas of the United States. This paper presents an overview of the program, the indicators and methods developed for the program, and some of the results after four years of monitoring and research. 相似文献
2.
Makino S Goto H Inoue T Sueyoshi M Okabe K Hasegawa M Hamaguchi K Ctanaka H Okochi I 《Environmental monitoring and assessment》2006,120(1-3):477-485
The results of a biodiversity monitoring program conducted in the Ogawa Forest Reserve and its vicinity, situated in a cool temperate region of Japan, identified three different patterns for species richness. Forests of the region are characterized by a mosaic of secondary deciduous stands of various ages scattered among plantations of conifers. The three different types of change in species richness observed in response to the stand age are as follows: Type I (butterflies, tube-renting bees and wasps, hoverflies, fruit flies, and longicorn beetles), the species diversity was highest in open areas, just after clear-cutting, decreasing with the stand age; Type II (mushrooms and mites associated with them), older stands showed greater diversity than younger stands; and, Type III (moths, oribatid mites, collembolas, carabid beetles, and ants), the number of species did not change greatly with the stand age, though ordination analysis revealed that there was variation in species compositions. These results indicate that combinations of stands of different ages, or heterogeneously arranged stands, can contribute to the maintenance of insect biodiversity at the landscape level. 相似文献
3.
The sensitivity of an integrated model to assess the potential for wind-borne spread of foot-and-mouth disease (FMD) to variations
in key parameters controlling different physical and biological processes was evaluated. The estimated number of farms at
risk is sensitive to the virus strain used and the accompanying effective contact rate. The C Noville strain increased the
estimated number of exposed farms ranked as high and medium risk of being infected by a factor of 5, compared to the baseline,
based on the O UKG 2001 strain. The inclusion of a model for biological ageing of the virus can also have a significant effect
on the concentration patterns arising from transport and dispersion of the virus. Its inclusion has the practical advantage
of markedly reducing the time required for the calculations. The estimated number of farms affected by exposure to high and
medium virus concentrations is not grossly sensitive to attenuation caused by temperature or relative humidity effects. Changes
in susceptibility to infection, as determined by the parameter θ in the exposure-risk model, does not change the configuration of the virus plumes, but it does change the distribution of
farms at risk by risk category. These findings suggest that a good understanding of characteristics (excretion rates from
infected animals, susceptibility of different species to infection, virus survival, etc.) of the virus strain involved in
an FMD outbreak is necessary to provide a reliable assessment of the risk of wind-borne spread. In the event of an incursion
of FMD, provision for laboratory studies on the virus will be an essential component of the disease response and should be
factored into contingency plans.
相似文献
X. YangEmail: |
4.
Ambient Air Quality Monitoring Network Design for Assessing Human Health Impacts from Exposures to Airborne Contaminants 总被引:1,自引:0,他引:1
Existing methods of establishing ambientair quality monitoring networks typically evaluateonly parameters related to ambient concentrations ofthe contaminant(s) of interest such as emissionsource characteristics, atmospheric transport anddispersion, secondary reactions, depositioncharacteristics, and local topography. However,adverse health risks from exposures to airbornecontaminants are a function of the contaminant andthe anatomic and physiologic characteristics of theexposed population. Thus, ambient air qualitymonitoring networks designed for the protection ofpublic health or for epidemiological studiesevaluating adverse health impacts from exposures toambient air contaminants should account for bothcontaminant characteristics and human healthparameters. A methodology has been establishedwhich optimizes ambient air quality monitoringnetworks for assessments of adverse human healthimpacts from exposures to airborne contaminants byincorporating human health risk assessmenttechniques. The use of risk assessment techniquesas the basis for designing ambient air qualitymonitoring networks will help to target limitedfinancial and human resources to evaluate humanhealth risks from exposures to airbornecontaminants. 相似文献
5.
6.
Lino J. Alvarez-Vázquez Gerardo Casal Aurea Martínez Miguel E. Vázquez-Méndez 《Environmental Modeling and Assessment》2017,22(4):279-289
In this work, we propose a technique to automatically optimize the monitoring of any distributed indicator (concentration of a substance along a river, blood pressure of a patient over time, etc.) for which a reliable estimate is previously available. From a mathematical point of view, the problem is based on obtaining a reliable estimate of the chosen indicator (e.g., by numerical simulation), and then solving a multi-objective optimization problem (with mixed real and integer variables) whose solution must provide an efficient and satisfactory monitoring strategy. As an illustrative case, we show the steps to follow in order to implement that strategy when designing a system for monitoring water quality in a river. Finally, we present and analyze the results when applying the proposed technique to study a real case in the Neuse River (North Carolina, USA). 相似文献
7.
Frédéric Babonneau Alain Bernard Alain Haurie Marc Vielle 《Environmental Modeling and Assessment》2018,23(6):611-626
In the meta-modeling approach, one builds a numerically tractable dynamic optimization or game model in which the parameters are identified through statistical emulation of a detailed large scale numerical simulation model. In this paper, we show how this approach can be used to assess the economic impacts of possible climate policies compatible with the Paris Agreement. One indicates why it is appropriate to assume that an international carbon market, with emission rights given to different groups of countries will exist. One discusses the approach to evaluate correctly abatement costs and welfare losses incurred by different groups of countries when implementing climate policies. Finally, using a recently proposed meta-model of game with a coupled constraint on a cumulative CO2 emissions budget, we assess several new scenarios for possible fair burden sharing in climate policies compatible with the Paris Agreement. 相似文献
8.
Amrita G. Desoyza Walter G. Whitford Sandra J. Turner Justin W. Van Zee Alan R. Johnson 《Environmental monitoring and assessment》2000,64(1):153-166
The most important function of watersheds in the western U.S. is the capacity to retain soil and water, thereby providing stability in hydrologic head and minimizing stream sediment loads. Long-term soil and water retention varies directly with vegetation cover. Data on ground cover and plant species composition were collected from 129 sites in the Rio Grande drainage of south-central New Mexico. This area was previously assessed by classification of Advanced Very High Resolution Radiometry (AVHRR) imagery. The classification of irreversibly degraded sites failed to identify most of the severely degraded sites based on size of bare patches and 35% of the sites classified as degraded were healthy based on mean bare patch size and vegetation cover. Previous research showed that an index of unvegetated soil (bare patch size and percent of ground without vegetative cover) was the most robust indicator of the soil and water retention function. Although the regression of mean bare patch size on percent bare ground was significant (p < 0.001), percent bare ground accounted for only 11% of the variability in bare patch size. Therefore bare patch size cannot be estimated from data on percent bare ground derived from remote sensing. At sites with less than 25% grass cover, and on sites with more than 15% shrub cover, there were significant relationships between percent bare soil and mean bare patch size (p < 0.05). Several other indicators of ecosystem health were related to mean bare patch size: perennial plant species richness (r = 0.6, p < 0.0001), percent cover of increaser species (r = 0.5, p < 0.0001) and percent cover of forage useable by livestock (r = 0.62, p < 0.0001). There was no relationship between bare patch size and cover of species that are toxic to livestock. In order to assess the ability of western rangeland watersheds to retain soil and water using remote sensing, it will be necessary to detect and estimate sizes of bare patches ranging between at least 0.5 m in diameter to several meters in diameter. 相似文献
9.
Forest area figures, at a given point in time and for a given region of interest, differ considerably, affecting the calculation of deforestation rates and thus confuse the political and scientific discussion on the state and change of the resource forest. This article discusses the variation of published forest cover figures, using Costa Rica as an example. A list of published figures on the forest cover of Costa Rica from 1940 onwards is analyzed. Reasons for the differences are hypothesized and discussed. These differences are mainly in the definition of forest and forest classes included, in the type of the studies conducted (mapping and/or sampling), in the precision of the estimates, and in the information sources used. It is concluded that part of the problem is inherent in the nature of the resource `forest'. Quality and completeness of the presentation of the forest cover estimates are a clue to their correct understanding and interpretation. The latter point being especially relevant, as forest cover data have both a technical-scientific and a political meaning and are used as relevant arguments in many discussions. In the example of Costa Rica, a general downward trend is observed up to about 1985/1990, whereas after that forest area figures are on the average at a markedly higher level. Some hypotheses for this change in the trend are discussed. 相似文献
10.
A new approach to Assess Atmospheric Nitrogen Deposition by Way of Standardized Exposition of mosses
A standardized method of moss exposition for assessing variations in nitrogen deposition was tested in the western part of
Germany. Six pleurocarpous moss species were transplanted to two sites differing in their deposition rates but being comparable
as to their climatic conditions. The mosses were exposed in standardized containers over a period of 12 months; the focus
of interest was the effect of N deposition on nitrogen content and on 15N natural abundance (δ15N-values). Within the first nine months only trends could be observed. However, after one year all species tested showed significantly
higher N concentrations at the highly polluted site. Besides, more negative δ15N-values possibly reflecting the higher ammonium input were detected at this site. Surprisingly, most of the plants though
being kept in plastic containers without a favourable substratum did not show any conspicuous deficiency symptoms. The potential
advantages of a standardized moss exposition for N monitoring purposes are discussed. It is concluded that the method presented
here can yield significant results in particular if the number of testing sites is increased. 相似文献
11.
Alexei V. Uvarov 《Environmental monitoring and assessment》2000,60(3):337-357
Long-term charcoal production in small private charcoal kilns (CK) in Eastern Bieszczady Mts. (SE Poland) can cause local smoke contamination of the ambient forest environment. Responses of model soil systems, contaminated or not contaminated by CK smoke, to contrasting combinations of hydrothermic regimes were compared in laboratory microcosms (respiration of soil community, decomposition rate of soil organic matter and cotton stripes, herb seeds germination were studied). The majority of the obtained data show a markedly higher level of soil biological activity in the CK versus the control series. In some cases CK and control soil systems show different patterns of reactions to the tested combinations of microclimate regime. These phenomena should at least partly be attributed to the effects of CK pollution. 相似文献
12.
Lyons J 《Environmental monitoring and assessment》2006,122(1-3):239-258
I developed a fish-based index of biotic integrity (IBI) to assess environmental quality in intermittent headwater streams in Wisconsin, USA. Backpack electrofishing and habitat surveys were conducted four times on 102 small (watershed area 1.7–41.5 km2), cool or warmwater (maximum daily mean water temperature ≥22 C), headwater streams in spring and late summer/fall 2000 and 2001. Despite seasonal and annual changes in stream flow and habitat volume, there were few significant temporal trends in fish attributes. Analysis of 36 least-impacted streams indicated that fish were too scarce to calculate an IBI at stations with watershed areas less than 4 km2 or at stations with watershed areas from 4–10 km2 if stream gradient exceeded 10 m/km (1% slope). For streams with sufficient fish, potential fish attributes (metrics) were not related to watershed size or gradient. Seven metrics distinguished among streams with low, agricultural, and urban human impacts: numbers of native, minnow (Cyprinidae), headwater-specialist, and intolerant (to environmental degradation) species; catches of all fish excluding species tolerant of environmental degradation and of brook stickleback (Culaea inconstans) per 100 m stream length; and percentage of total individuals with deformities, eroded fins, lesions, or tumors. These metrics were used in the final IBI, which ranged from 0 (worst) to 100 (best). The IBI accurately assessed the environmental quality of 16 randomly chosen streams not used in index development. Temporal variation in IBI scores in the absence of changes in environmental quality was not related to season, year, or type of human impact and was similar in magnitude to variation reported for other IBI's. 相似文献
13.
P. A. Addison 《Environmental monitoring and assessment》1989,12(1):39-48
In Canada, acid rain is the generic term encompassing all forms of air pollution — wet and dry deposition, gaseous pollutant concentrations, and airborne particulates. It was because these pollutants, alone or in combination, may directly or indirectly affect the heath of Canada's forests, that in 1984, the Canadian Forestry Service initiated a national forest monitoring program (Acid Rain National Early Warning System or ARNEWS).Research studies on pollutant effects of the past 15–20 years have demonstrated that it is not possible to define specific symptoms of acid rain or mixtures of pollutants on native tree species or specific responses of the forest ecosystem. Consequently, ARNEWS monitored incipient acid rain effects by determining the forest's state of health rather than by concentrating on specific pollutant responses.The detection system entails experienced insect and disease survey forest rangers assessing both specific plots and the forest as a whole for extraordinary forest damage. The techniques used include mensurational and symptomatological measurements as well as evaluation of stands for damage from natural and anthropogenic causes. Critical also to the system was the capability of the Canadian Forestry Service to support the detection system with research staff who could carry out studies to explain any abnormalities in forest condition detected during the annual surveys. The ultimate outcome of the monitoring system if unexplained forest damage is detected is a research project on possible causes.Contribution from Fourth World Wilderness Congress — Acid Rain Symposium, Denver (Estes Park), Colorado, September 11–18, 1987. 相似文献
14.
David A. Degenhardt Christian C. Fromuth 《Environmental monitoring and assessment》1993,26(2-3):235-247
The Oregon Department of Forestry is a designated management agency to provide a forestry program to assist in bringing the Tualatin River into complicance with pH and dissolved oxygen water quality standards. The Oregon Environmental Quality Commission set a total maximum daily load (TMDL) of 70 µg/l total phosphorus to control algae growth and meet these standards. The Department of Forestry has a basin effectiveness monitoring plan to determine that the Oregon Forest Practice Rules' BMPs are maintaining adequate control of phosphorus loadings from forest operations. Three sites monitored during May to October of 1990 were augmented by eight more sites in 1991. As laboratory methods were refined, the results became more accurate. The 1991 monitoring showed lower phosphorus levels that were consistent for each tributary. Mean total phosphorus levels ranged from 17 to 65 µg/l. Preliminary field reconnaissance suggests a correlation between phosphorus levels and underlying geology. Concentrations were lowest at sites underlain by tertiary intrusive basalts, next higher for sites with terrestrial basalt, next higher for one site with a basalt-sandstone bedrock mix, and highest for sites underlain predominately by sandstone. These results may be modified by 1992 monitoring and further analysis. 相似文献
15.
Strobl RO Robillard PD Shannon RD Day RL McDonnell AJ 《Environmental monitoring and assessment》2006,112(1-3):137-158
The principal instrument to temporally and spatially manage water resources is a water quality monitoring network. However,
to date in most cases, there is a clear absence of a concise strategy or methodology for designing monitoring networks, especially
when deciding upon the placement of sampling stations. Since water quality monitoring networks can be quite costly, it is
very important to properly design the monitoring network so that maximum information extraction can be accomplished, which
in turn is vital when informing decision-makers. This paper presents the development of a methodology for identifying the
critical sampling locations within a watershed. Hence, it embodies the spatial component in the design of a water quality
monitoring network by designating the critical stream locations that should ideally be sampled. For illustration purposes,
the methodology focuses on a single contaminant, namely total phosphorus, and is applicable to small, upland, predominantly
agricultural-forested watersheds. It takes a number of hydrologic, topographic, soils, vegetative, and land use factors into
account. In addition, it includes an economic as well as logistical component in order to approximate the number of sampling
points required for a given budget and to only consider the logistically accessible stream reaches in the analysis, respectively.
The methodology utilizes a geographic information system (GIS), hydrologic simulation model, and fuzzy logic. 相似文献
16.
Archambault DJ Li X Foster KR Jack TR 《Environmental monitoring and assessment》2006,115(1-3):509-530
Ethephon, which releases ethylene within plant tissues after application, was chosen to perform assessments of the relative sensitivity of crops to ethylene and to determine which stages of plant development were most sensitive. The species chosen were: barley, wheat, oats, canola and field pea, all of which are important crops in the province of Alberta, Canada. Plants were treated with ethephon at one of 7 different stages. Plants were assessed for their vegetative and reproductive growth, including height, biomass, yield and seed quality. Visual symptoms were photographed and documented to compare them with symptoms caused by ethylene applied as a gas. It was concluded that in barley, wheat and canola the late vegetative and early reproductive stages were most sensitive, at least when sensitivity was defined as reductions in yield and quality. As for field pea, ethephon had no effect on yield but did cause increased numbers of pods, which in certain conditions could lead to increased yields. Significant effects on vegetative growth were only observed in the early vegetative stages of development but with no effects on yield. The screening protocol successfully identified sensitive cultivars and growth stages for further investigation of the effects of ethylene exposure. 相似文献
17.
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
18.
John Boland Olena Kravchuk Wasim Saman Rowan Kilsby 《Environmental Modeling and Assessment》2003,8(2):101-113
The provision of energy for households is a major contributor to greenhouse gas emissions in the domestic sector. There is significant scope for energy savings and thus emission reduction in this sector. This paper constructs a bridge between thermal analysis and environmental assessment in the occupancy stage of the dwelling life cycle, approaching both methods as being on a common system Environment–Dwelling–Inhabitant. The importance of the local level in the thermal analysis and assessment of either a dwelling or an inhabitant's behaviour is demonstrated. It is shown that the researcher can choose between natural experiment, computer experiment and mathematical modelling to analyze the system. Such a choice is discussed for two particular methods of thermal analysis. Thermal Nomograms are the result of mathematical modelling, and the Energy Score Sheet is the result of a computer experiment in energy rating. Despite being developed for the purpose of thermal analysis, these methods can also be utilized for environmental assessment at the local level. The discussion centres on Australian conditions where the majority of the population resides in a relatively benign climate wherein behavioural alterations have significant potential for energy savings and environmental impact. The purpose of the paper is to emphasise benefits apart from energy minimisation to promote the use of energy efficient housing strategies. 相似文献
19.
Sensitivity of a Land Change Model to Pixel Resolution and Precision of the Independent Variable 总被引:1,自引:0,他引:1
It is important to know how the results from a land change model vary based on both the pixel resolution of the maps and the
precision of the independent variables because subjective decisions or default values frequently determine these two factors.
This paper presents an approach to measure the variation in model accuracy that is triggered by alteration of the pixel resolution
and the precision of the independent variable, which are bins of distance to previously built area for our case study. We
illustrate the principles with an application of the Geomod land change model contained in the Idrisi GIS, applied to simulate the gain of built land in central Massachusetts, USA. Results reveal four general principles: (1)
change in pixel resolution using the majority-takes-all rule can influence quantity error, (2) change in bin width of an independent
variable does not influence the quantity error, (3) resolution and bin width interact so that bin width does not have an effect
on error when bin widths are smaller than the pixel resolution, and (4) researchers are wise to examine the implications of
their subjective decisions by plotting clearly how the resolution and bin size influence the mathematical relationships that
the model uses. We have found no universal, hard, and fast rules that dictate how to decide on an appropriate pixel resolution
and bin width, but our method demonstrates how these decisions can be influential. These insights can offer scientists guidance
in how to prepare data in an appropriate manner. 相似文献