Cumulative Impact Assessment Research Articles

Cumulative impact assessment for Sindh barrages

There are 19 barrages constructed on the Indus River to divert water to irrigate command areas for crop production and for flood control. The Guddu barrage is one such barrages, which requires rehabilitation and is the subject of the current study. There are two barrages, Sukkur and Kotri which are located downstream of Guddu barrage, whose impacts are also considered as part of the cumulative impact assessment. The objective of the study is to evaluate the cumulative impact as a result of the rehabilitation of the barrage. The construction of barrages and diversion of water for irrigation has resulted in negative and positive impacts on many valued environmental components including: (i) fragmentation of dolphins’ habitat and extirpation of dolphins in many river sections of the Indus and its tributaries, (ii) restriction of hilsa migration has resulted in drastic reduction in commercially important hilsa fish catch and its spawning area, and (iii) transformation of the arid barren lands of Sindh in to vast agricultural lands, which has resulted in significant socioeconomic benefits to Sindh.

A Global Review of Cumulative Pressure and Impact Assessments in Marine Environments

Ever more extensive use of marine space by human activities and greater demands for marine natural resources has led to increases in both duration and spatial extent of pressures on the marine environment. In parallel, the global crisis of decreasing biodiversity and loss of habitats has revitalized scientific research on human impacts and lead to methodological development of cumulative pressure and impact assessments (CPIA). In Europe alone, almost twenty CPIAs have been published in the past 10 years and some more in other sea regions of the world. In this review, we have analysed 36 recent marine CPIAs and focused on their methodological approaches. We were especially interested in uncovering methodological similarities, identifying best practices and analysing whether the CPIAs have addressed the recent criticism. The review results showed surprisingly similar methodological approaches in >50% of the studies, raising hopes for finding coherence in international assessment efforts. Although the CPIA methods showed relatively few innovative approaches for addressing the major caveats of previous CPIAs, the most recent studies indicate that improved approaches may be soon found.

Effects of model assumptions and data quality on spatial cumulative human impact assessments

AbstractAimMany studies have quantified and mapped cumulative human impacts on marine ecosystems. These maps are intended to inform management and planning, but uncertainty in them has not been studied in depth. This paper aims to: (1) quantify the uncertainty in cumulative impact maps and related spatial modelling results; (2) attribute this uncertainty to specific model assumptions and problems with data quality; (3) identify and test sound approaches to such analyses.LocationWe used the Baltic Sea and the Mediterranean and Black Seas as example regions. The methods and conclusions are relevant for human impact mapping anywhere.MethodsWe conducted computational experiments to test the effects of nine model assumptions and data quality problems (factors) on maps of human impact and related modelling results. The factors were implemented on the basis of a literature review. We quantified aggregate uncertainty using Monte Carlo simulations, and ranked the factors by their influence on modelling results using the elementary effects method. Both methods are well established and theoretically suitable for complex models, but had to be modified for application to spatial human impact models.ResultsSome, but not all, modelling results were robust. This contradicts previous studies that found only minor effects of the factors they tested. Of the nine factors tested here, eight had a considerable influence on at least one modelling result in at least one of the two study regions.Main conclusionsModel assumptions and data quality have larger aggregate effects on maps of human impact than found in previous analyses. These effects depend on the study region and the data that describe it. Future human impact mapping studies should thus include comprehensive uncertainty analyses. Computational experiments allow us to distinguish robust from less reliable modelling results and to prioritize improvements in models and data.

A pressure–state–response approach to cumulative impact assessment

Cumulative impact assessment (CIA) is particularly challenging when several projects from different proponents are presented simultaneously for a region. The impacts of such projects are typically assessed individually, but approaches and methods commonly applied to single-project impact assessment may not be adequate to such problems. The pressure–state–response (PSR) model was adapted to tackle cumulative impacts of ten projects concentrated in an iron ore mining region in Southeastern Brazil. Using information from individual assessments, a set of indicators was built to depict current and future pressures on valued environmental and social components, to describe the current and to derive trends for the future state of the environment, and to review mitigation responses. It was found that the future state will likely be critical for both air and water quality, possibly stable for natural vegetation, due to the likely combined result of rehabilitation and offsets, and for both cultural heritage and public roads, due to likely effect of mitigation. Relying on individual assessments proved to be unsatisfactory, because key information on both the characteristics of the projects and baseline are largely inconsistent across studies and presented in very different formats. An indicator-based PSR approach to CIA is information-intense and is recommended only when databases are reliable and built on the basis of standard protocols. The need to better understand cumulative impacts and to provide corresponding, landscape or watershed scale, mitigation and management responses could be a driver for a more widespread and consistent use of standardized indicators in individual impact assessments.

Anthropogenic disturbances and their impact on vegetation in Western Himalaya, India

The present study assesses anthropogenic disturbances and their impacts on the vegetation in Western Himalaya, India on the basis of various disturbance parameters such as density, Total Basal Cover (TBC) of cut stumps, lopping percentage and grazing intensities. On the basis of canopy cover and frequency of disturbances (%), the studied forests were divided into highly disturbed (HD), moderately disturbed (MD) and least disturbed (LD) categories. The HD forests had the lowest canopy cover, lowest density and lowest TBC and the LD had the highest canopy cover, highest density and highest TBC. The MD forests occupied the intermediate position with respect to these parameters. Species richness was least in HD forests, highest in one of the MD forests while LD forest occupied an intermediate position. The percentage of regenerating species was lowest (54%) in HD and highest (72%) in MD. The density of seedlings and saplings was higher in one of the MD forests as compared to HD and LD. We concluded that the moderate disturbances do not affect the vegetation adversely; however the increased degree of disturbance causes loss in plant diversity; affects regeneration and changes community characteristics. Construction of hydroelectric projects at various places in the study area was found to be one of the most important sources of anthropogenic disturbances in addition to the routine anthropogenic disturbances like grazing, fuelwood collection and fodder extraction. If all proposed dams in the Indian Himalaya are constructed combined with weak national environmental impact assessment and implementation, it will result in a significant loss of species. Therefore, various agents of disturbances should be evaluated in cumulative manner and any developmental activities such as hydropower projects, which trigger various natural and anthropogenic disturbances, should be combined with proper cumulative environmental impact assessment and effective implementation to minimise the anticipated loss of vegetation.

How cumulative impact assessment supports maritime spatial planning?

How cumulative impact assessment supports maritime spatial planning?

High school incompletion and childhood maltreatment among street-involved young people in Vancouver, Canada.

While the link between educational attainment and future health and wellness is well understood, little investigation has considered the potential impacts of distinct forms of childhood maltreatment on high school completion. In the present study, the relationship between five categories of childhood maltreatment (physical, emotional, and sexual abuse, and physical and emotional neglect) and completion of high school education were examined using the Childhood Trauma Questionnaire (CTQ). From September 2005 to May 2013, data were collected for the At-Risk Youth Study (ARYS), a cohort of street-involved young people who use illicit drugs in Vancouver, Canada. We used logistic regression to examine the relationship between childhood maltreatment and high school completion, while controlling for a range of potential confounding variables. Specifically, five separate models for each category of maltreatment and two combined models were employed to examine the relative associations between, and cumulative impact of, different forms of childhood maltreatment and educational attainment. Among 974 young people, 737 (76%) reported not completing high school. In separate multivariable analyses physical abuse, emotional abuse, physical neglect, and emotional neglect remained positively and independently associated with an incomplete high school education. In a combined multivariable model with all forms of childhood maltreatment considered together, emotional abuse (adjusted odds ratio=2.08; 95% confidence interval: 1.51-2.86) was the only form of maltreatment that remained significantly associated with an incomplete high school education. The cumulative impact assessment indicated a moderate dose-dependent trend where the greater the number of different forms of childhood maltreatment the greater the risk of not completing a high school education. These findings point to the need for trauma-informed interventions to improve educational attainment among vulnerable young people, as well as evidence-based prevention programmes, such as the Nurse-Family Partnership, aimed at supporting at-risk families before maltreatment occurs.

Coal, Cumulative Impacts, and the Great Barrier Reef

AbstractThe Great Barrier Reef World Heritage Area, Australia, covers over 348,000 km2 of tropical marine ecosystems of global significance. In July 2015, the World Heritage Committee called attention to the cumulative impacts of climate change, poor water quality, and coastal development on the region's outstanding universal value, but stopped short of inscribing the Great Barrier Reef on the List of World Heritage in Danger. Restoring the region's values is hindered by an environmental decision‐making process that fails to incorporate cumulative impacts, including the climate change impacts of greenhouse gas emissions sourced from one of Australia's largest exports, thermal coal. We identify policy and processes that enable a more comprehensive consideration of the cumulative effects of coal mining by environmental decision‐makers. Implementing cumulative impact assessment requires a collaborative and transparent program of planning and monitoring independent of Government and mine proponents that evaluates local, regional, and global impacts. The future of the Great Barrier Reef depends on transformational change in the cumulative assessment of Australian coal mines.

Assessing cumulative visual impacts in coastal areas of the Baltic Sea

Anthropogenic activity such as offshore wind energy farm development, shipping activity, resource extraction platforms or marine aquaculture can have adverse impacts on the visual quality of coastal landscapes. GIS-based viewshed analysis is the most widely used technique to address visual impacts. However, despite the wide application its spatial extent remains limited to local and regional studies. This study presents a GIS-based model for cumulative visual impact assessment on macro-regional scale based on a case study for the Baltic Sea. The viewshed model was deployed over a visibility zone covering 54% (223.641 km2) of the Baltic Sea space using a database of 63,672 observation points integrated by geospatial data on existing and planned sea uses representing potential visual stressors. Results show that areas of highest potential visual impact are sheltered coastal areas with complex geomorphological features such as barrier islands, peninsulas, straits, archipelagos and lagoons in combination with intensive anthropogenic activity and presence of nature protected areas. The methodology can be applied to any coastal area of the world to classify coastal areas due to their cumulative viewshed characteristics and as early monitoring tool for visual impact assessment on transboundary scale.

The Asset Drivers, Well-being Interaction Matrix (ADWIM): A participatory tool for estimating future impacts on ecosystem services and livelihoods

Building an effective response for communities to climate change requires decision-support tools that deliver information which stakeholders find relevant for exploring potential short and long-term impacts on livelihoods. Established principles suggest that to successfully communicate scientific information, such tools must be transparent, replicable, relevant, credible, flexible, affordable and unbiased. In data-poor contexts typical of developing countries, they should also be able to integrate stakeholders’ knowledge and values, empowering them in the process. We present a participatory tool, the Asset Drivers Well-being Interaction Matrix (ADWIM), which estimates future impacts on ecosystem goods and services (EGS) and communities’ well-being through the cumulative effects of system stressors. ADWIM consists of two modelling steps: an expert-informed, cumulative impact assessment for EGS; which is then integrated with a stakeholder-informed EGS valuation process carried out during adaptation planning workshops. We demonstrate the ADWIM process using examples from Nusa Tenggara Barat Province (NTB) in eastern Indonesia. The semi-quantitative results provide an assessment of the relative impacts on EGS and human well-being under the ‘Business as Usual’ scenario of climate change and human population growth at different scales in NTB, information that is subsequently used for designing adaptation strategies. Based on these experiences, we discuss the relative strengths and weaknesses of ADWIM relative to principles of effective science communication and ecosystem services modelling. ADWIM’s apparent attributes as an analysis, decision support and communication tool promote its utility for participatory adaptation planning. We also highlight its relevance as a ‘boundary object’ to provide learning and reflection about the current and likely future importance of EGS to livelihoods in NTB.

Cumulative impact assessment on air quality from multiple open pit mines

Both open pit mine and smelter projects can have significant impacts on a variety of environmental resources. Among these, air quality of the surroundings is a key issue. Additionally, the environmental assessment of projects demands integrated approach taking in account all pollution sources. Therefore, specific focus has been put on the methodology for assessing impacts on air quality. This paper proposes an integrated index of environmental impact aiming to quantify the air quality impact of industrial operations around an urban area, in case of scarcity of in situ acquired data. This proposed pollution index is demonstrated by a case study conducted in the municipality of Congonhas, Brazil, in which contributions of five open pit mines and two smelters were studied. To achieve the pollution index, the wind rose and distances from the centroids of effective areas to the urban nucleus itself were considered, taking into account the wind projection areas from windward impacting sources on the leeward impacted urban site. The proposed index also includes the squared wind speed (proportional to the kinetic energy transferred in uplifting dust from ground surface). The method proposed is considered suitable for impact assignment for each one of the air pollution sources in the neighborhood of studied area. Some fluid dynamic aspects of airborne particulate matter are also studied by proposing a new equation for threshold saltation speed.

Many a little makes a mickle: Cumulative land cover changes and traditional land use in the Kyrö reindeer herding district, northern Finland

Traditional land use systems are threatened by land use intensification and resulting land cover transitions in northern areas. This article examines cumulative land cover changes and their impacts on reindeer grazing grounds in the Kyrö reindeer herding district in northern Finland. Land cover transitions were studied using Landsat TM and OLI images and topographic maps. The results showed that the herding district has experienced notable land cover changes during the past decades, and most of these changes were directly related to forestry. The proportion of continuous coniferous forests of the total forest cover declined from 92% to 78% between 1987 and 2013. Approximately one third of the forests outside current conservation areas were disturbed by forest management by 2013, and remaining forests were notably more fragmented than forests within conservation areas. The extent of the road and path networks expanded considerably between 1960s and 2010 as a result of increasing logging and tourism. Accumulation of disturbances gradually results in loss of key resources and declined quality of the landscape mosaic from the reindeer herding perspective, which can pose a serious threat to long-term sustainability of the livelihood. Rapid land cover changes in non-protected areas highlight an increasingly important role of conservation areas in maintaining resources for reindeer husbandry in the face of intensifying land use. Sustainable management of resources outside conservation areas requires careful participatory planning and efficient cumulative impact assessment of different land use activities.

Baltic Sea biodiversity status vs. cumulative human pressures

Many studies have tried to explain spatial and temporal variations in biodiversity status of marine areas from a single-issue perspective, such as fishing pressure or coastal pollution, yet most continental seas experience a wide range of human pressures. Cumulative impact assessments have been developed to capture the consequences of multiple stressors for biodiversity, but the ability of these assessments to accurately predict biodiversity status has never been tested or ground-truthed. This relationship has similarly been assumed for the Baltic Sea, especially in areas with impaired status, but has also never been documented. Here we provide a first tentative indication that cumulative human impacts relate to ecosystem condition, i.e. biodiversity status, in the Baltic Sea. Thus, cumulative impact assessments offer a promising tool for informed marine spatial planning, designation of marine protected areas and ecosystem-based management, and may prove useful for setting limits on allowable levels of human impact on ecosystems.

Towards a cumulative collision risk assessment of local and migrating birds in North Sea offshore wind farms

Bird collision assessments are generally made at the scale of a single wind farm. While especially in offshore situations such assessments already hold several assumptions, even bigger challenges exist on estimating the cumulative impact of multiple wind farms and the impacts at population level. In this paper, the number of collision victims at Belgian offshore wind farms was estimated with a (theoretical) collision risk model based on technical turbine specifications, bird-related parameters and bird density data of both local seabirds and passerine migrants. Bird density data were gathered by visual censuses and radar registrations. The outcome of the model was extrapolated to future development scenarios in the Belgian part of the North Sea and in the entire North Sea, and then further used for a preliminary assessment of the impact at population level for the species at risk. The results indicate that the cumulative impact of a realistic scenario of 10,000 turbines in the North Sea might have a significant negative effect at population level for lesser and great black-backed gull. We further show that during a single night of intense songbird migration, the number of collision victims among passerine migrants might be in the order of magnitude of several thousands in the entire North Sea. We argue that it is of great importance to further develop methods to quantify the uncertainties and to minimise the assumptions, in order to assure more reliable cumulative impact assessments.

From the Seam to the Stove: greenhouse gas assessment and the coal seam gas industry in Australia

ABSTRACTIn Australia, Coal Seam Gas (CSG) is a relatively new source of natural gas commonly advocated as a lower greenhouse gas (GHG) emissions alternative to coal. This study investigates how GHG emissions have been, and potentially could be, assessed within the Australian CSG industry. The research involved a document analysis of several Environmental Impact Statements (EISs) and consultant reports prepared as part of the Environmental Impact Assessment (EIA) process for major CSG projects in New South Wales (NSW) and Queensland (Qld). There were found to be inconsistencies in the conduct of greenhouse assessment by the CSG industry, including how complete and transparent assessments were, as well as how effectively they addressed project emission intensity and cumulative impacts. There were also found to be large inconsistencies between assessments carried out for Qld projects and those for NSW projects, likely because of differences in how assessment requirements are applied by planning bodies. This study also highlights how alternative assessment approaches, such as Cumulative Impact Assessment (CIA) and Strategic Environmental Assessment (SEA), have potential to enable a broader and more consistent understanding of emission sources that cross a range of geographical and project boundaries.

Research on the Methods of Cumulative Environment Impact Assessment in the High-Speed Railway Region

Combined with the characteristics of the high-speed railway regional environment system, the paper establishes a cumulative environment impact assessment model with the system dynamics in the high-speed railway regional, which is divided into three subsystems: economic, environment and pollution subsystems. Each subsystem is refined into a number of state indexes. The feedback relationships is set up between each state index and various subsystems, based on the Matrix method, Delphi, Analytic Hierarchy Process and environmental carrying capacity to establish comprehensive evaluation model of the cumulative environment impact assessment in the high-speed railway region. Finally the Chang-Yi high-speed railway is taken as an example.This paper is of the important theory and practice significance to promote the cumulative impact assessment level and social environment benefit of the high-speed railway regions.

The uneven distribution of environmental burdens and benefits in Silicon Valley's backyard

Inequalities in the exposure to environmental burdens and access to environmental benefits are an environmental justice concern for urban and regional environmental planning. Recent studies have assessed the exposure of different populations to a combination of environmental hazards through GIS-based Cumulative Environmental Impact Assessments (CEIA). The contribution of this study is the development of a CEIA, which incorporates the distance-based impact of transportation, the cumulative impact of environmental hazards, and access to environmental benefits for Santa Clara County (SCC), a highly diverse and rapidly developing region also known as ‘Silicon Valley’. Our results show that social vulnerability, cumulative environmental hazards, and environmental benefits exhibit distinct spatial patterns in SCC. High environmental hazard values are found along freeway and railroad corridors with substantial industrial legacies, while environmental benefit scores are generally higher in the suburban periphery. Correlations indicate that socially vulnerable populations in SCC are predominantly hispanic and are more likely to be exposed to environmental hazards, while white and wealthier populations are more likely to have access to environmental benefits. The results from this study may serve to develop community-based initiatives for neighborhood improvement and environmental-justice-based regional planning and public health policy reform.

Renewable energy developments in an uncertain world: The case of offshore wind and birds in the UK

As marine renewable energy applications are increasing in the UK, environmental and cumulative impacts and their assessments are receiving considerable attention. The uncertainty, particularly surrounding cumulative impacts, however remains high and is becoming a cause of delay in the consenting process. This study examines the sources of uncertainty in environmental impact assessments and provides recommendations as to how these may be reduced, using the example of birds and wind farms. In the assessment of environmental impacts, uncertainty not only enters through the availability of empirical data but also data collection and analysis methods, linguistics and policy frameworks. Identifying and quantifying sources of uncertainty in environmental and cumulative impact assessments is critical to facilitating the development of an environmentally sustainable offshore wind industry.

A method proposal for cumulative environmental impact assessment based on the landscape vulnerability evaluation

Cumulative environmental impact assessment deals with the occasional use in practical application of environmental impact assessment process. The main reasons are the difficulty of cumulative impact identification caused by lack of data, inability to measure the intensity and spatial effect of all types of impacts and the uncertainty of their future evolution. This work presents a method proposal to predict cumulative impacts on the basis of landscape vulnerability evaluation. For this purpose, qualitative assessment of landscape ecological stability is conducted and major vulnerability indicators of environmental and socio-economic receptors are specified and valuated. Potential cumulative impacts and the overall impact significance are predicted quantitatively in modified Argonne multiple matrixes while considering the vulnerability of affected landscape receptors and the significance of impacts identified individually. The method was employed in the concrete environmental impact assessment process conducted in Slovakia. The results obtained in this case study reflect that this methodology is simple to apply, valid for all types of impacts and projects, inexpensive and not time-consuming. The objectivity of the partial methods used in this procedure is improved by quantitative landscape ecological stability evaluation, assignment of weights to vulnerability indicators based on the detailed characteristics of affected factors, and grading impact significance.

Definition and applications of a versatile chemical pollution footprint methodology.

Because of the great variety in behavior and modes of action of chemicals, impact assessment of multiple substances is complex, as is the communication of its results. Given calls for cumulative impact assessments, we developed a methodology that is aimed at expressing the expected cumulative impacts of mixtures of chemicals on aquatic ecosystems for a region and subsequently allows to present these results as a chemical pollution footprint, in short: a chemical footprint. Setting and using a boundary for chemical pollution is part of the methodology. Two case studies were executed to test and illustrate the methodology. The first case illustrates that the production and use of organic substances in Europe, judged with the European water volume, stays within the currently set policy boundaries for chemical pollution. The second case shows that the use of pesticides in Northwestern Europe, judged with the regional water volume, has exceeded the set boundaries, while showing a declining trend over time. The impact of mixtures of substances in the environment could be expressed as a chemical footprint, and the relative contribution of substances to that footprint could be evaluated. These features are a novel type of information to support risk management, by helping prioritization of management among chemicals and environmental compartments.