Restoration Scenarios Research Articles

Defining spring foraging habitat and prioritization of conservation sites for Tricolored Blackbirds in California, USA

Abstract The Tricolored Blackbird (Agelaius tricolor) is a range-restricted, colonial-nesting species in decline. Colonies include tens of thousands of individuals that forage in the surrounding landscape, at times commuting miles between nesting and foraging grounds. We explored the role of landscape composition on colony occupancy and mapped core and potential spring foraging habitat in California, USA. We used observations of spring Tricolored Blackbird nesting colonies from 2008, 2011, and 2014 and characterized changes in the surrounding landscape during an extended drought. Then, we constructed occurrence and abundance models in order to map core foraging habitat across 4 ecoregions in California. Finally, we used simulated land cover changes to identify potential habitat under restoration scenarios. Across the 3 survey years, surface water declined over time at unoccupied colony locations but remained stable at occupied colony locations, confirming that permanent surface water was a critical feature of persistent Tricolored Blackbird colonies. Average percent cover of nearly all land cover types suitable for foraging, as well as frequency of dairies and median NDVI, were all higher in current or historical colony sites than elsewhere. The proportion of surrounding alfalfa, grasslands, and surface water were the elements of foraging habitat best able to predict Tricolored Blackbird early breeding season colony presence and colony size. Core foraging habitat covered over 6 million acres in the study region, but only 18% was occupied in 2014. This result suggests a need to study additional factors determining colony occurrence and persistence, such as landscape connectivity, distributions of nesting substrates, and risk from predators. The vast majority (93.1%) of Tricolored Blackbird core habitat occurred on private land; therefore, saving the species will require engagement and partnership with private landowners.

Using Meta-Analysis for Large-Scale Ecosystem Service Valuation: Progress, Prospects, and Challenges

AbstractThis article discusses prospects and challenges related to the use of meta-regression models (MRMs) for ecosystem service benefit transfer, with an emphasis on validity criteria and post-estimation procedures given sparse attention in the ecosystem services literature. We illustrate these topics using a meta-analysis of willingness to pay for water quality changes that support aquatic ecosystem services and the application of this model to estimate water quality benefits under alternative riparian buffer restoration scenarios in New Hampshire's Great Bay Watershed. These illustrations highlight the advantages of MRM benefit transfers, together with the challenges and data needs encountered when quantifying ecosystem service values.

Effects of Slope Ecological Restoration on Runoff and Its Response to Climate Change.

Slope ecological restoration and climate change are important factors affecting the hydrological processes of the Huangshui River Basin in Qinghai province, China. How to quantitatively identify the impact of slope ecological restoration on runoff and whether slope ecological restoration can mitigate the impact of future climate change on runoff are both very important. In this paper, the Huangshui River above the center of Minhe county was taken as the research area, and the Pinus tabulaeformis and shrubs were taken as the main forest land types of slope ecological restoration. First, based on the law of forest land variation, the construction scales of slope ecological restoration in different periods were identified. The influence of slope ecological restoration on runoff was then quantitatively evaluated by using a distributed hydrological model. Second, the future climate scenarios of five general circulation models (GCMs) under three representative concentration pathways (RCPs) (i.e., RCP2.6, RCP4.5, and RCP8.5) from 2021 to 2050 were selected and modified by model integration. Combined with the slope ecological restoration scenarios, the influence of slope ecological restoration on runoff under future climate scenarios was explored. The results showed that the effect of slope ecological restoration was significant. Compared with 1980, the area of slope ecological restoration increased by 24% in 2017. Under the present climate conditions (1960–2017), different periods of slope ecological restoration have an effect on the process of runoff in the wet season (June, July, August, and September) and dry season (January, February, March, and December), which eliminates the maximum, replenishes the minimum, and reduces the variability of runoff processes in the watershed. Under the future climate scenario (2021–50), slope ecological restoration will reduce runoff. On the other hand, climate change will increase runoff, and the combination of the two effects will have a certain offsetting effect. On the whole, comparing the influence of slope ecological restoration on the runoff process with that of climate change in different seasons, due to the main influence of slope ecological restoration, the runoff decreased by about 55% in the temperate season (April, May, October, and November), and increased by about 50% in the dry season or wet season due to the main influence of future climate scenarios.

Reactivation of Floodplains in River Restorations: Long‐Term Implications on the Mobility of Floodplain Sediment Deposits

AbstractNowadays, national and international requirements and laws emphasize the “natural” development of river‐floodplain systems. One goal is to increase the connectivity between the river and its floodplains and thus reactivate floodplains as flooding areas, which potentially increases the mobility of fine sediments. The objective of this study is to analyze the long‐term effects of reactivated floodplains on the mobility of floodplain deposits of small rivers based on two river restoration scenarios: elevating the riverbed or lowering the floodplains. Past channel fixation and degradation as well as the subsequent increase in the floodplain elevation led to the decoupling of the channel and floodplain morphodynamics associated with the reduction of the habitat connectivity. Here, the floodplain sedimentation rates were determined using a numerical model based on the Delft3D software. The novelty of these numerical investigations is the morphological long‐term analysis over timescales of decades, which is not comparable to other short‐term hydrodynamic and morphodynamic studies for small meandering lowland rivers. The results of 11 river restoration scenarios show that lowering the floodplain and raising the riverbed elevation both lead to an increase in the fine sediment deposition on the floodplain. However, lowering the floodplain elevation is generally more effective. Based on the numerical model results and the assumption of a fixed river channel, only anthropogenic activity might have increased the amount of fine sediments deposited on floodplains and has accelerated the decoupling of the floodplains from the riverbed in the past centuries.

A multi-indicator spatial similarity approach for evaluating ecological restoration scenarios

The greater Everglades region in Florida (USA) is an area of wetlands that has been altered and reduced to 50% of its original area and faces multiple threats. Spatial landscape analysis can help guide a large and complex ecosystem restoration process, involving billions of dollars and multiple groups of stakeholders. To guide Everglades restoration efforts, we evaluated ecological performance of different hydrologic restoration scenarios using a novel technique, the structural similarity index (SSIM), which quantitatively compares similarity between pairs of gridded maps in terms of mean, variance, and covariance. Using the SSIM, we evaluated system-wide performance of apple snails, American alligators, Great egrets, and long- and short-hydroperiod vegetation types under multiple restoration scenarios that varied in water management strategies, amounts of water storage, removal of levees and canals (decompartmentalization), and seepage control barriers. We then compared species and habitat responses under each restoration scenario to a target scenario simulating the historical, natural system. The SSIM approach provides a reliable means of scenario comparison, accounting for both the local magnitude and spatial structure of the underlying data. Our results demonstrated that decompartmentalization benefits the indicator species. In general, scenarios with increased water storage were closer to the target scenario. This spatial comparison technique is useful for evaluating restoration efforts at multiple spatial scales, ranging from the entire ecosystem down to individual compartments or sub-compartments. The results can be used to inform management and restoration efforts and to guide policy for the greater Everglades area.

Pairwise-Comparison-Based Rank Learning for Benchmarking Image Restoration Algorithms

Image restoration has attracted substantial attention recently and many image restoration algorithms have been proposed for restoring latent clear images from degraded images. However, determining how to objectively evaluate the performances of these algorithms remains an open problem, which may hinder the further development of advanced image restoration techniques. Most image restoration-quality metrics are designed for specific restoration applications; hence, their generalization ability is limited. For benchmarking image restoration algorithms, the ranking of restored images that are generated via various algorithms, is the most heavily considered factor. Inspired by this, this paper presents a pairwise-comparison-based rank learning framework for benchmarking the performances of image restoration algorithms, which focuses on the relative quality ranking of restored images. Under the proposed framework, we further propose a general image restoration quality metric by integrating quality-aware features in both the spatial and frequency domains. The proposed metric exhibits good generalization performance, and it is applicable to various restoration applications. The results of extensive experiments that were conducted on eight public databases of five restoration scenarios demonstrate the superior performance of the proposed method over the existing quality metrics. Moreover, the proposed framework is used to improve the existing quality metrics for benchmarking image restoration algorithms and highly encouraging results are obtained.

Estimating the benefits of restoration And preservation scenarios of marine biodiversity: An application of the contingent valuation method

Marine biodiversity provides valuable benefits for human beings. Some of these benefits, such as the provision of food, are easily recognized, while some, such as climate regulation, are less well-known. People lack direct experience of the economic value of marine biodiversity, since no relevant market exists. This study reports the results of a contingent valuation study to estimate people’s willingness to pay (WTP) for biodiversity restoration and conservation scenarios in some unique coralligenous habitats in the North Adriatic Sea, Italy.Coralligenous habitat constitutes one of the most important ‘hot spots’ of species diversity in the Mediterranean, notoriously affected by a loss of biodiversity as a consequence of human activities, such as over-fishing and pollution, sediment deposition, recreational fishing, trawling, and diving. A major threat is the increasing frequency of abandoned, lost, or otherwise discarded fishing gear at sea.A sample of 4000 Italian people was surveyed, and the results show that people’s WTP for interventions aimed at improving biodiversity through the removal and restoration operations in the area is distinctly higher than is the WTP for the preservation and prevention of further biodiversity loss. The findings suggest that respondents perceive prevention and control activities as being embedded in restoration, the benefits of which can be seen within a certain time frame. Positive and significant determinants of respondents’ WTP are family income, knowledge of biodiversity in coralligenous habitat, previous cognizance and awareness of marine biodiversity issues, environmental friendly behavior, and concern for environmental quality.

Composition and Diversity of Areas Under Restoration Process From the Brazilian Atlantic Forest

The evaluation of the forest restoration scenario is of great importance, with floristic composition and diversity being among the most used ecological variables as indicators. This research aimed to identify the current situation, in terms of species composition and diversity, of two riparian forests under restoration based on a reference ecosystem, the Brazilian Atlantic Forest. Twenty permanent plots (250 m²) were located in areas under restoration process (AR1 and AR2) and in a forest fragment of the region which served as a reference ecosystem (ER). We sampled, identified and classified all tree individuals with CBH ≥ 15.0 cm in each plot. Aiming to understand species richness and diversity, besides the traditional indexes (Shannon and Simpson), we also estimated the effective numbers of Hill’s diversity (qD = 0, 1 and 2) considering rarefaction (P ≤ 0.05); and to detect floristic similarities among the study areas we performed a Principal Coordinate Analysis (PCoA). We found dissimilarity among ARs and ER, and the presence of exotic species, indicating that, as recommended, such reference should have been taken into account during the planning of the restoration action. Considering the effective numbers of species (qD) we found differences between the areas, species richness and diversity was higher in ER > AR2 > AR1. We also show that among the restoration areas, with the same age and submitted to the same conditions, AR2 has features that allow us to conclude that this area has a bigger chance of success in the restoration process. However, aiming environmental sustainability, we suggest that some corrective actions should be taken in order to favour the reestablishment of ecological processes in these areas.

The Active Reef Restoration Toolbox is a Vehicle for Coral Resilience and Adaptation in a Changing World

The accelerating marks of climate change on coral-reef ecosystems, combined with the recognition that traditional management measures are not efficient enough to cope with climate change tempo and human footprints, have raised a need for new approaches to reef restoration. The most widely used approach is the “coral gardening” tenet; an active reef restoration tactic based on principles, concepts, and theories used in silviculture. During the relatively short period since its inception, the gardening approach has been tested globally in a wide range of reef sites, and on about 100 coral species, utilizing hundreds of thousands of nursery-raised coral colonies. While still lacking credibility for simulating restoration scenarios under forecasted climate change impacts, and with a limited adaptation toolkit used in the gardening approach, it is still deficient. Therefore, novel restoration avenues have recently been suggested and devised, and some have already been tested, primarily in the laboratory. Here, I describe seven classes of such novel avenues and tools, which include the improved gardening methodologies, ecological engineering approaches, assisted migration/colonization, assisted genetics/evolution, assisted microbiome, coral epigenetics, and coral chimerism. These are further classified into three operation levels, each dependent on the success of the former level. Altogether, the seven approaches and the three operation levels represent a unified active reef restoration toolbox, under the umbrella of the gardening tenet, focusing on the enhancement of coral resilience and adaptation in a changing world.

Spatial optimizations of multiple plant species for ecological restoration of the mountainous areas of North China

Intensive human land use and climate change have led to widespread ecological degradation which requires optimizing species distributions to achieve ecological restoration. In this paper, we combine predictive species distribution models (SDMs) with field investigations in the mountainous areas of northern China to determine where ecological restoration should be implemented. Using three species distribution models, i.e., generalized additive models (GAMs), generalized linear models, and classification tree models, we predict optimal species algorithms for ecological restoration. The results show that GAMs have more accurate predictive power to detect relationships between biogeographic factors and species distributions than the other two models based on cross-validation. In addition, the regionalization schemes designed in this study provide scientific guidance for ecological restoration by combining simulation results of SDMs with field investigations. By considering the suitability of different land use/cover types, restoration scenarios could be used to guide ecological restoration. The methodology proposed here provides a scientific basis for the restoration of species diversity, improved ecosystem services provision, and can be adopted in regions with extensive human disturbance and environmental change.

Integrating Sunda clouded leopard (Neofelis diardi) conservation into development and restoration planning in Sabah (Borneo)

Changes in land use/cover are the main drivers of global biodiversity loss, and thus tools to evaluate effects of landscape change on biodiversity are crucial. In this study we integrated several methods from landscape ecology and landscape genetics into a GIS-based analytical framework, and evaluated the impacts of development and forest restoration scenarios on landscape connectivity, population dynamics and genetic diversity of Sunda clouded leopard in the Malaysian state of Sabah. We also investigated the separate and interactive effects of changing mortality risk and connectivity. Our study suggested that the current clouded leopard population size is larger (+26%) than the current carrying capacity of the landscape due to time lag effects and extinction debt. Additionally, we predicted that proposed developments in Sabah may decrease landscape connectivity by 23% and, when including the increased mortality risk associated with these developments, result in a 40–63% decrease in population size and substantial reduction in genetic diversity. These negative impacts could be mitigated only to a very limited degree through extensive and targeted forest restoration. Our results suggest that realignment of roads and railways based on resistance to movement, without including mortality risk, might be misleading and may in some cases lead to decrease in population size. We therefore recommend that efforts to optimally plan road and railway locations base the optimization on effects of development on population size, density and distribution rather than solely on population connectivity.

Assessment of river bed evolution with the aid of 2D hydrodynamic model with integrated sediment transport modeling capabilities

The aim of the study is to assess hydro-morphologic evolution of currently cut off meander for 3 river restoration scenarios during 10 days of bank-full discharge. To simulate hydro-morpho-dynamics...

Tidal Asymmetry Changes in a Shallow Mud Estuary by a Restoration Project

The tidal asymmetry-induced siltation below tidal barriers is a worldwide problem that restricts regional socio-economic and environmental development. The hydrodynamic processes of the small mud estuary also feature a high uncertainty after estuary restoration measures. In this study, a hydrodynamic model based on the MIKE21 is used to quantify the responses of tidal asymmetry to a two-phase restoration project in Shuanglong Estuary, Bohai Bay, China. According to the numerical modeling results, the tidal flat removal in the upper estuary (first-phase restoration) induces the flood asymmetry switching to the ebb asymmetry in unrestored reach but enhances flood asymmetry in widening restored reach. Although the tidal asymmetry reverts to flood-dominated pattern after full restoration over the estuary, the imbalance between flood and ebb velocities is relieved. A possible net sediment transport pattern based on a comparison of dominant asymmetric current and actual sediment transport period shows net sediments in the upper estuary and inlet transport seaward and landward, respectively, in the first-phase restoration, whereas landward net sediment transport occurs in the whole estuary under the second-phase restoration scenario. Given these results, we assume that a switch from the flood-dominated estuary to ebb-dominated estuary can be caused by redesigning the cross-sectional profile. The quantitative comparison of Lagrangian residual currents also implies that a channel–shoal structure rather than a flat bathymetry can promote the mass transport. Therefore, reshaping the channel–tidal flat system in restoration projects can prevent the sedimentation of the estuary and improve the water environment.

Hydrodynamic Modeling Improves Green River Reconnection with Floodplain Wetlands for Endangered Fish Species Recovery

AbstractWe performed two‐dimensional (2D) hydrodynamic modeling to aid recovery of the endangered razorback sucker (Xyrauchen texanus) by reconnecting the Green River with its historic bottomland floodplain wetlands at Ouray National Wildlife Refuge, Utah. Reconnection allows spring flood flows to overtop the river levee every two to three years, and passively transport razorback sucker larvae to the wetlands to grow in critical habitat. This study includes (1) river hydrologic analysis, (2) simulation of a levee breach/weir, overtopping of river flood flows, and 2D flow through the wetlands using Hydrologic Engineering Center River Analysis System 2D, and (3) modeling flow and restoration scenarios. Indicators of hydrologic alteration were used to evaluate river flow metrics, in particular flood magnitudes, frequency, and duration. Results showed a target spring flow of 16,000 cfs (453 m3/s) and a levee breach elevation of 4,663 ft (1,421 m) amsl would result in a median flow >6,000 acre‐feet (7.4 million m3) over five days into the wetlands, which is adequate for razorback sucker larvae transport and rearing. Modeling of flow/restoration scenarios showed using gated water control structures and passive low‐water crossings between wetland units can provide adequate control of flow movement into and storage in multiple units. Levee breaching can be a relatively simple, cost‐effective method to reconnect rivers and historic floodplains, and hydrodynamic modeling is an important tool for analyzing and designing wetland reconnection.

Could restoration of a landscape to a pre‐European historical vegetation condition reduce burn probability?

AbstractMontane regions throughout western North America have experienced increases in forest canopy closure and forest encroachment into grasslands over the past century; this has been attributed to climate change and fire suppression/exclusion. These changes threaten ecological values and potentially increase probabilities of intense wildfire. Restoration of landscapes to historical conditions has been proposed as a potential solution. We used historical oblique photographs of an area in the Rocky Mountains of Alberta, Canada, to determine the vegetation composition in 1909 and then asked whether restoration to a historical vegetation condition would: (1) reduce the overall burn probability of fire; (2) reduce the probability of high‐intensity fires; and (3) change the spatial pattern of burn probabilities, as compared to current conditions. We used the Burn‐P3 model to calculate the overall and high‐intensity burn probabilities in two scenarios: (1) the baseline (current (2014) vegetation composition) and (2) historical restoration (vegetation in the study area as of 1909 with the surrounding landscape in its current condition). In the baseline, the landscape had 50% less grassland and more coniferous forest than 100 yr ago. Except for the fuel grids, we ensured all input parameters (number and locations of ignitions, weather conditions, etc.) were identical between the two scenarios; therefore, any differences in outputs are solely attributable to the changed fuels. The historical restoration scenario reduced the overall burn probability by only 1.3%, but the probability of high‐intensity wildfires was reduced by nearly half (44.2%), as compared to the baseline scenario. There were also differences in the spatial pattern of overall burn probabilities between the two scenarios. While 6.7% of the landscape burned with half (or less) the probability in the restoration scenario (compared to the baseline), other areas (3.2%) had burn probabilities two to five times higher. More than 21.5% had high‐intensity burn probabilities that were 20% or less of those in the baseline scenario. Differences in burn probabilities between the two scenarios were largely attributable to the effects of the vegetation difference on rate of fire spread. Restoration to historical vegetation structure significantly lowered wildfire risk to the landscape.

Spatial distribution of grassland soil organic carbon and potential carbon storage on the Qinghai Plateau

AbstractMapping the soil organic carbon (SOC) properties of terrestrial ecosystems is necessary to mitigate carbon flux. Here, we quantified grassland SOC contents and densities to evaluate the potential for increased storage through recovery on the Qinghai Plateau. The SOC contents of 41 paired soil profiles from areas of nondegraded and degraded grasslands were analyzed in 2012 using a dry oxidation method. The average SOC contents of nondegraded and degraded grasslands were 3.4 ± 0.3% and 2.4 ± 0.4% (p < 0.05). The SOC density changes varied from −5.5 to 13.2 kg/m2 in a future grassland restoration scenario. The predicted main regions of potential increasing SOC density were located in the counties Zhiduo, Qilian, Menyuan, Maduo, Gande and Zeku. Moreover, the potential SOC stock would increase by 0.83 pg due to grassland restoration, suggesting a key role of alpine grassland as carbon sink on the Qinghai Plateau.

A trade-off method between environment restoration and human water consumption: A case study in Ebinur Lake

The shrinkage of inland lakes has become a major problem in arid region. Human activities are competing for water resources with sustainable lake ecosystem. Considering improving irrigation efficiency does not help on water saving at basin scale and reducing ET through mulching, zero tillage and deficit irrigation will lead to crop yield loss, this study proposed an alternative way that returning cropland to lake to achieve the balance between endorheic lake restoration and human water consumption. The approach consists of four procedures: (1) identifying the target annual inflow (Qtar) of endorheic lake; (2) calculating available consumable water (ACW) in the upstream based on Qtar; (3) setting ET deduction goals using water consumption balance approach; (4) estimating crop area to be deducted. This approach is implemented at Ebinur Lake of China under two restoration scenarios (lake area restored to 522 km2 and 800 km2). The results indicate that to restore the Ebinur Lake to 522 km2, the annual inflow should be increased to 602.6 × 106 m³, and human water consumption should be reduced by 320.3 × 106 m³. If the restoration goal of Ebinur Lake is set to 800 km2, an annual inflow of 876.6 × 106 m³ is required, and the human water consumption should be reduced by 594.2 × 106 m³. The over-expansion of cropland and artificial forest is found to be the main reasons for the shrinkage of Ebinur Lake. Finally, the feasible solutions for ecosystem restoration of Lake Ebinur are provided for both scenarios. The methodology adopted in this research can be applied to the restoration of other inland lakes in arid regions.

Material suplementario Artículo 71275. Diagnóstico ecológico, formulación e implementación de estrategias para la restauración de un bosque seco tropical interandino (Huila, Colombia)

Anexo 1. Área de estudio y escenarios de restauración donde se implementaron las estrategias de restauración ecológica (RE).Anexo 2. Metodología de evaluación rápida de barreras y facilitadores de la restauración ecológica.Anexo 3. Trayectorias ecológicas esperadas para cada escenario de regeneración.Anexo 4. Especies priorizadas y propagadas para las estrategias de restauración ecológica del bosque seco tropical (bs-T).Anexo 5. Esquemas de las estrategias de restauración y fotografías de su implementación, por escenario de restauración.

How Changes in Legally Demanded Forest Restoration Impact Ecosystem Services: A Case Study in the Atlantic Forest, Brazil

The recent change in Brazilian laws reduced the amount of area that is set aside for native vegetation restoration in rural private properties. However, we lack estimates of its impacts on the provisioning of key ecosystem services at local scales. Therefore, in a microwatershed in the Brazilian Atlantic Forest hot spot, we quantified the impact of the change from the Forest Code (1965) to the Native Vegetation Protection Law in Brazil (2012) on future native forest cover, biomass carbon stocks, and soil loss and sedimentation. We analyzed three scenarios: (a) the land use and cover as of 2016, (b) the Forest Code, 1965, and (c) the Native Vegetation Protection Law, 2012. In each scenario, we modeled soil loss and sedimentation (InVEST, Revised Universal Soil Loss Equation) and calculated the carbon stocks. The 2012 law implementation would increase forest cover (15.6%), decrease soil sedimentation (1.12%) and loss (1.13%), and increase carbon stock (5.4%). However, compared to the Forest Code, it would reduce the area for restoration and the potential for native forest cover growth, increase soil loss and sedimentation potential, and limit increases in carbon stocks at the landscape level. In both restoration scenarios, the potential percent increase in forest cover in the microwatershed owing to the laws is higher than the percent decrease in soil loss and sedimentation. These findings have the potential to elucidate the effect of laws on ecosystem services and be useful to those planning the creation, modification, and implementation of laws for forest restoration in private properties.

Material suplementario Artículo 71318. Monitoreo de la restauración ecológica en un bosque seco tropical interandino (Huila, Colombia): programa y resultados preliminares

Anexo 1. Mapa de ubicación geográfica del área de estudio y escenarios de restauración ecológica.Anexo 2. Escenarios de restauración descritos para el área de estudio. Tomado y adaptado de Torres-Rodríguez et al. 2019.Anexo 3. Modelos de arreglos florísticos de estrategias de restauración implementadas y seleccionadas para resultados preliminares de efectividad ecológica.Anexo 4. Metas y objetivos de restauración redefinidos para el programa de monitoreo del proceso de restauración iniciado con el proyecto piloto.Anexo 5. Unidades de implementación y monitoreo (respuesta) para el seguimiento o evaluación de la efectividad ecológica de estrategias de restauración implementadas en el área de estudio.Anexo 6. Tasas de crecimiento neto en altura y DAB en un año, de las especies sembradas en las tres estrategias de restauración seleccionadas para la presentación de resultados preliminares.