Today, land degradation and the decrease in the expected services of watersheds have been mainly influenced by human-induced activities. Hence, it requires more attention to adaptively manage and ...provide feasible solutions to watershed disruptions. However, appropriate management of precious commodities such as water, soil, air, and vegetation cover needs insight planning on a proper scale. Nonetheless, such an integrated approach to comprehensive health assessment of watershed resources is yet to be indoctrinated by scholars, implemental agencies, managers, and policymakers. Accordingly, the present endeavor has tried to evaluate the health status of Iran's 30 second-order large watersheds with the pressure-state-response (PSR) approach. In this regard, 44 problem-oriented, influential, and, at the same time, accessible variables with compatible scales at the national level were primarily determined in climatic, hydrologic, anthropogenic, and natural sectors. The collinearity-free and independent variables were then finalized using the variance inflation factor (VIF) test. Ultimately, P, S, and R indices were calculated using the arithmetic mean of 25 normalized variables based on which PSR-based health and security indices were also mapped countrywide. The results indicated that P, S, and R indices varied from 0.49 to 0.69, 0.42 to 0.82, and 0.40 to 0.94, respectively. Health and security indices ranged from 0.46 to 0.69 and 0.30 to 0.89, respectively. The weighted mean of P, S, and R was 0.59, 0.62, and 0.67, respectively, wholly placing them in the intermediate class. The weighted health and security indices were also 0.58 and 0.59, representing the intermediate class. The results showed that study watersheds had different health and security conditions from interplaying watershed-specific factors. The results revealed the necessity of watershed-unique managerial strategies to cope with the existing unfavorable conditions at the country level. However, further insight with high resolution is recommended for the high-priority watersheds to plan implementation and executive projects.
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•Watershed health and security atlases were developed for I.R. Iran.•The Pressure-State-Response (PSR) conceptual model was employed for the assessment.•Health and security variability was studied at 30 second-order watersheds in Iran.•The weighted health and security indices of Iran's watersheds were found moderate.•High-priority watersheds need high-resolution studies for executive projects.
Decision-making resource stewardship models rely on statistical relationships between management actions and ecosystem services provisioning. The operationalization of management actions benefits ...from models capable to isolate synergic statistical relationships from trade-offs. We showcase two existing watershed planning studies requiring spatiotemporal operationalization to better schedule management actions. The study in Hawai'i Island (USA) focused on invasive species while another in Babeldaob Island (Republic of Palau) tackled wildfire management. Both planning exercises relied on Ecosystem Management Decision Support to populate hydrologically defined management units for supporting water resource decision-making. In this viewpoint we identify shortcomings and potential future directions aligned with shaping stewardship responses to the interactive constraints of climate mitigation and management costs within a very needed optimization framework capable to operationally support landscape managers and drive solutions on ES management and valuation.
Planning multistage implementation plans, or roadmaps, based on the spatial distribution of a best management practice (BMP) scenario is essential for achieving watershed management goals under ...realistic conditions, such as stepwise investment plans that involve multiple stakeholders, including investors, economic and environmental beneficiaries. The state-of-the-art BMP roadmap optimization method can address this need for optimization but is over-specialized and complex to non-expert stakeholders. This study designed a user-friendly web-based participatory watershed planning system to assist a diverse group of stakeholders in reaching a consensus on optimal roadmaps. The participatory process of stakeholders includes iteratively proposing stepwise investment constraints, submitting roadmap optimization tasks, analyzing spatiotemporal results from multiple perspectives, and selecting preferred roadmaps. The proposed system design separates the participatory process of non-expert stakeholders from the specialized modeling process of constructing simulation-optimization tools for BMP roadmaps, which is done in advance by professional modelers and encapsulated as webservices on the server side. The webservices expose a small set of essential parameters to lower barriers to use. The interactive participatory process is presented to stakeholders through web browsers with an easy-to-use interface. The system design was evaluated by implementing an agricultural watershed planning system for soil erosion reduction and conducting a role-playing experiment involving three groups of stakeholders with different standpoints in proposing investment constraints. The experimental results show that the optimal roadmap sets exhibit progressive improvements across three-round optimizations started by different stakeholders, effectively capturing the varying perspectives of stakeholders and facilitating consensus-building among them. The idea of system design and example implementation can serve as a valuable reference for developing related user-friendly environmental decision support systems.
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•System design meets practical watershed management needs for agreed-upon roadmaps.•System separates easy-to-use interface for non-expert users from specialized models.•Browser/Server system facilitates participatory processes of multiple stakeholders.•Users participate in proposing investment plans and electing optimized roadmaps.•Multi-stakeholder role-play experiment verifies system's validity and practicality.
Water for life in Alberta, Canada Schultz, Juliane; Baijius, Warrick; Patrick, Robert J
Canadian Planning and Policy,
07/2023, Volume:
2023, Issue:
1
Journal Article
Peer reviewed
Open access
Water is integral to Alberta’s economy, grounded in agriculture, power generation, extractive industry, tourism, and recreation. In 2003, the Government of Alberta released the Water for Life ...Strategy (the Strategy) amidst growing public concerns over multiple impacts on provincial water resources. The Strategy is a framework document guiding the development of watershed plans across the provincial landscape to be implemented by Watershed Protection and Advisory Committees (WPACs). This paper explores the extent to which First Nations in Alberta were included in the government’s development of the Strategy and in the implementation of the Strategy by the WPACs. Our research data was gathered through key informant interviews with WPAC personnel as well as content analysis of relevant planning documents from provincial and WPAC sources. The research results point to an absence of First Nations inclusion in both the development of the provincial water Strategy as well as the implementation of the Strategy through the WPAC policies and plans. The results also identify institutional gaps and opportunities by which the provincial government and the WPACs may engage more effectively and inclusively with Indigenous communities. From our analysis, we recommend a series of institutional arrangements to advance far greater inclusion of Indigenous voices and recognition of Indigenous peoples as rights-holders, in watershed planning in Alberta.
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•A new framework successfully identified flood hotspots in an urban drainage system.•Inlet structure depth was found to be the main parameter that predicts flooding.•GSI can ...significantly mitigate stormwater inlet floods.•Combining GSI and gray infrastructure provides the most effective mitigation.•Cost of overflow mitigation from GSI is lower than gray infrastructure.
Mitigation of localized pluvial flooding is one of the major resiliency goals in urban environments, and Green Stormwater Infrastructure (GSI) has the potential to deliver such an outcome. However, there is a lack of systematic approaches to prioritize investment in different candidate areas. This study provides a framework to identify vulnerable stormwater drainage inlets and their contributing areas, prioritize them, identify dominant factors in their selection, assess the potential of GSI in mitigating their overflows, and compare the impact and its cost to gray infrastructure upgrade alternatives. Using SWMM 5.1.013, decision trees, and a volumetric-based assessment of GSI overflow capture, we applied the framework to the City of Dallas, Texas, for three design storms with three GSI practices— bioretention cells, raingardens, and rainwater harvesting tanks. Results showed that there was a significant increase in the number of overflowing stormwater drainage inlets, referred to as hotspots, and their contributing subwatersheds, referred to as opportunity areas, with more intense storms especially in problematic watersheds. Also, prioritization results provided a series of maps to rank the opportunity areas based on overflow severity, recurrence of the overflows, and GSI availability. Moreover, classification results showed that inlet features, especially the inlet depth, were the dominant factors in the identification of the non-problematic inlets. Finally, the GSI impact assessment showed substantial overflow mitigation even at the “very high” severity levels when GSI is comprehensively deployed across opportunity areas. Despite gray infrastructure upgrades yielding higher reduction levels, their cost per cubic meter was higher than GSI. Therefore, a combination of GSI and gray results in maximum overflow reduction at a lower cost compared to common practices.
Normative and descriptive multi-criteria decision analysis methods were compared to understand their differences in providing decision insights, with a wetland restoration planning study, Chesapeake ...Bay watershed, USA. Excessive nutrient and sediment runoff is causing impaired water quality and degradation of aquatic habitat in the Chesapeake Bay. A team at The Nature Conservancy evaluated a decision to prioritize large-scale wetland restoration opportunities. A total of 964 potentially restorable wetland alternatives were delineated using spatial analysis. The alternatives were evaluated on seven water quality and climate resilience criteria. Normative methods included ranking the alternatives based on scaling and averaging criteria values per alternative using value and distance functions. Descriptive methods included grouping the alternatives based on their statistical similarities and dissimilarities using principal component analysis. Sensitivity analysis incorporated different data transformations based on risk and riskless decision contexts, different criteria weighting scenarios, and two formats for grouping alternatives. The descriptive method provided inherent information about tradeoffs that normative methods did not, whereas the normative methods provided a similar type of information about tradeoffs. Inherent tradeoff information can provide useful decision insights without complicated criteria scaling and weighting methods, which can be favorable to researchers that desire a more objective analysis. However, descriptive methods do not guarantee favorable results and should be considered along with preferences and judgments. Multiple methods can guide a more comprehensive approach to thinking about tradeoffs in other similar contexts.
Supporting data are available on request: David.Martin@tnc.org.
•Multi-criteria decision analysis used to evaluate a wetland restoration decision.•Normative and descriptive methods are compared for similarities and dissimilarities.•Risk and riskless contexts evaluated.•Results emphasize differences between normative and descriptive methods.•Case study in Chesapeake Bay watershed, USA.
•Boosted regression tree model is robust in charactering nonlinear non-point source pollution generation and transport processes.•The nonlinear responses of critical source areas to influencing ...factors was evaluated quantitatively.•The thresholds for influencing factors can provide supportive information for watershed management.•Land use and fertilizer application have higher importance in determining the occurrence of critical source areas.•Machine learning techniques have great potential for predicting critical source areas under climate change.
Critical Source Areas (CSAs) are areas that contribute disproportionate high levels of non-point source (NPS) pollution to receiving waters, and their occurrence is the result of the complex interaction between the factors related to the sources and transport processes of NPS pollution. A systematic understanding of how these influencing factors affect CSAs is essential for successful watershed management. In this study, we applied a statistical data mining technique boosted regression tree model to quantify the contribution of eight influencing factors (soil type, slope, elevation, RUSLE LS factor, RUSLE K factor, runoff, fertilizer application rate and land use) on two types of CSAs (TN-CSAs and TP-CSAs), as well as the marginal effects and potential thresholds of influencing factors on the occurrence of CSAs. Results show that land use (37.35%, 25.03%), fertilizer application (36.93%, 57.83%) and soil type (17.59%, 13.70%) have higher importance in determining the occurrence of TN-CSAs and TP-CSAs; and the incidence of TN-CSAs is positively correlated with most factors before the threshold for each influencing factor, after which the marginal effect largely leveled off or dropped slightly; TP-CSAs have essentially the same characteristics as TN-CSAs, but TP-CSAs are more likely to occur in areas with an annual runoff of around 244.92 mm. In addition, this study discussed the application of machine learning techniques in predicting CSAs under climate change without physical-based models, as well as a preliminary watershed management planning for NPS pollution control in the study watershed. These results provided important information for nutrient management regulations.
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•RRV conceptual framework in respect to drought patterns was studied.•Foyle, Xarrama and Shazand watersheds with various climates were analyzed by RRV.•The study watersheds behaved ...differently in terms of RRV health assessment.•Drought based RRV index was more variable for Shazand than other watersheds.
Climate-related extremes such as droughts have led to significant impacts on some watersheds. To assess watershed health and develop effective management plans, information about the function and structure of the watersheds in the context of their climatic response, especially to take into account rainfall anomalies and climate change adaptation, is needed. Integration of climatic variables with reliability, resilience and vulnerability (RRV) indicators, is a novel approach for generating this information. This study investigated the behavior of RRV indicators with respect to rainfall variability and drought patterns for three watersheds governed by different climates. Reliability was defined as the probability of a watershed to be in the range of satisfactory Standardized Precipitation Index (SPI) values. Resilience was indicated as the speed of recovery from an unsatisfactory condition. Vulnerability was defined as a function of the exposure of a watershed to climate change and variation using the SPI. The study areas were the Foyle Watershed in Northern Ireland (temperate oceanic, Cfb), the Xarrama Watershed in Portugal (Mediterranean hot summer, Csa) and the Shazand Watershed in Iran (moderate to cold semi-arid (Bsk). Based on the SPI pattern of each watershed, the SPI of −0.1 for the Foyle and Xarrama watersheds and +0.1 for the Shazand Watershed was selected as the drought threshold. The drought based RRV index was subsequently calculated from long-term (1981–2012) RRV indicators, resulting in means of 0.52 ± 0.25, 0.53 ± 0.21 and 0.30 ± 0.18 for the three watersheds, respectively. These means reflect the status of the watersheds in terms of climatic conditions, which was moderate dry (0.41–0.60) for the Foyle and Xarrama watersheds and dry (0.21–0.40) for the Shazand Watershed. The temporal trend of the drought based RRV index was found to be non-significantly increasing (P-value >0.52) for the Foyle and Xarrama watersheds and non-significantly decreasing for the Shazand Watershed (P-value >0.48). The vulnerability indicator and drought based RRV index were significantly (p-value = 0.00) affected by the climatological gradient. The results of the conceptual framework linked to statistical trends can provide researchers, policy makers, and land managers a more comprehensive base to assess variability of watershed health and design drought management plans.
•A decision-scaling method counters drawbacks of downscaled global climate models.•SWAT model is effective integrating climate change to inform watershed planning.•Aggregated detentions are effective ...for climate change adaptation in a watershed.
Climate change is projected to have increased temperature and more frequent and intense rainfalls in the northeast of the United States. Green infrastructure has been identified as a critical strategy for stormwater management and flooding mitigation as well as for climate change adaptation. Climate science plays an important role in understanding a range of climate change impacts and the effects of green infrastructure for climate change planning. Nevertheless, a lack of down-scaled climate change data and place-based assessment has discouraged local communities to pursue further climate change plans. This study proposed a transdisciplinary planning framework assessing the effects of detention in mitigating climate change-induced flooding, using a case in the Charles River watershed, Massachusetts, USA. Derived from a climate sensitivity test in the watershed, 36 climate change conditions were modeled using Soil and Water Assessment Tool (SWAT) and compared to IPCC scenarios. Statistical analyses revealed that detention is more efficient in reducing flooding hazards in low and moderate emission scenarios than those at high emission scenarios. A range of extra land area designated for detention would be needed for mitigating floods under various climate change scenarios. Planning implications include the needs for effective siting of detention areas combined with soil conservation in watershed planning, innovations in adaptive land planning and urban design, and a call for an integration of climate science and hydrological assessment in the transdisciplinary planning processes to better inform and facilitate decision-making using green infrastructure for climate change adaptation in local communities.
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