Success Of Restoration Efforts Research Articles

Assessment of Temperate Deciduous Forest Communities and Structures after Restoration through the Multi-Reference Ecosystems Framework

The reference forest serves as a model for forest ecosystem restoration and can be employed to assess the vegetation of the Restored Forest, thereby confirming the success of restoration. When evaluating restoration, employing multireference forests is advantageous for discerning gradual changes in Restored Forests. However, in previous studies, their utilization has been limited to comparisons with individual ecosystems. Therefore, this study investigates the status of Restored Forests in previously damaged areas and their resemblance to reference forests across four forest types, namely Climax Forest (CF), Secondary Forest (SF), Restored Forest (RF), and Planted Forest (PF). Reference forests, serving as model targets for restoration, include CF and SF, while RF and PF represent the restoration forests. Six target sites within two temperate deciduous forests (Quercus acutissima and Quercus variabilis) were selected, and a comparative analysis of species diversity, dominance, and evenness was conducted. This study revealed that the dominant species in the top canopy of restoration forests mirrored those in reference forests, with Q. variabilis and Q. acutissima being prevalent. A similarity index of over 60% and a high correlation of 0.987 were observed in the top canopy layer between the reference and restored ecosystems (CF-RF/SF-PF). These findings enhance our understanding of the current status of Restored Forests and advocate for the utilization of multiple reference forests for successful restoration efforts.

Effects of grass functional diversity on invasion success by exotic grasses in Cerrado grasslands

Abstract Invasive species pose significant challenges to successful restoration efforts worldwide. A strategy to reduce invasions is to establish communities consisting of species with varied ecological strategies. These strategies typically align along the conservative and plant size axes, and more recently, along a below‐ground collaboration axis. However, we lack understanding of how the diverse ecological strategies of Cerrado grass species, their combinations and their interactions with soil conditions can mitigate invasions. Here, we investigated how native grass communities composed by species with different ecological strategies affect the invasion success in two soil types of abandoned pastures in the Cerrado. Specifically, we tested the hypothesis that greater above‐ and below‐ground functional diversity reduces exotic species invasion. We also evaluated whether the isolated effects of native species on invasion were positive or negative. We installed an experiment with species richness ranging from zero to eight native grass species. In November 2019, we sowed species combinations to create communities composed by species with different ecological strategies. We quantified the above‐ground biomass of exotic species as a measure of invasion. To characterize the species ecological strategies, we measured five functional traits. Functional diversity of maximum height and specific root length (SRL) had the highest predictive power; however, the most parsimonious model included only SRL diversity, which represents the collaboration axis. Native above‐ground biomass was also negatively related to exotic species biomass. Furthermore, invasion was greater in less stressful soil conditions but did not interact with diversity. The effect of native species varied from facilitation to competition, with the annual fast‐growing native species favouring invasion. Synthesis and applications. Our results show that greater functional diversity of combined above‐ and below‐ground traits reduces invasion success, shedding light on an underexplored role of specific root length diversity. The competitive and facilitative effects of different native species highlight the need for careful selection of the species to be used in restoration programmes. Furthermore, the absence of interaction between diversity and soil types highlights the need for an integrated management of the functional composition and edaphic factors to increase resistance to invasion in these Neotropical grass communities.

Small mammal associations with habitat composition, configuration, and management in tallgrass prairies: a review

Abstract Tallgrass prairie is among the most threatened ecosystems but is often fragmented and surrounded by human‐modified landscapes. Small mammals are integral components of tallgrass prairies. However, little is known about how landscape composition, configuration, and management impact small mammals in tallgrass prairies. We conducted a systematic literature review to identify species‐specific and community associations with three broad topics: landscape composition, landscape configuration, and management practices. We identified 61 studies that assessed our variables of interest. We categorised the location, species assessed, variables monitored, and results by species and for the community. The majority of studies (64%) were conducted in two states, Illinois and Kansas. Deer mice (Peromyscus maniculatus), prairie voles (Microtus ochrogaster), and white‐footed mice (Peromyscus leucopus) showed specific associations with landscape variables, with deer mice preferring bare ground and recently burned plots, and prairie voles preferring thatch and negatively associated with prescribed fire. White‐footed mice were frequently associated with wooded areas. Small mammal biodiversity was positively associated with patchy habitats containing greater diversity in vegetative composition and management regime. Management and land composition were both relatively well studied for several species; habitat configuration was understudied. We identified significant gaps in our understanding of small mammal landscape ecology in tallgrass prairies. With tallgrass prairie restoration a growing trend in this region, a greater understanding of drivers of small mammal populations will be crucial to successful restoration efforts. Future research should focus on understudied areas and species, and examine how habitat heterogeneity impacts small mammal biodiversity.

Evaluating ocean health and restoration success: A comprehensive study of the benthic quality index in the Bilbao estuary

Ocean health is a global concern, and effective protection and restoration of estuaries require robust ecological information and appropriate metrics for comprehensive assessments. This study used 16 years of hard-bottom macroinvertebrate data from the formerly polluted Bilbao estuary to calculate the Benthic Quality Index (BQI). The BQI, based on species sensitivity values derived from richness-disturbance associations, was a valuable tool for evaluating the health of the macroinvertebrate community. Our findings demonstrated the responsiveness of the BQI to both natural and anthropogenic stressors, making it a useful indicator for assessing overall community health. Significant increases in BQI values, averaging 47%, were observed in the central section of the estuary, indicating successful restoration efforts. Furthermore, the BQI values showed a positive correlation with distance from the river mouth, reflecting a gradient of improved health. Notably, the BQI reliance on data rather than species-specific knowledge makes it suitable for assessing benthic community health across large temporal and spatial scales, where ecological information may be limited. In conclusion, the BQI provides a standardized measure of health that facilitates a better understanding of the state of our oceans. Its application in assessing estuarine health, as demonstrated in the Bilbao estuary, underscores its value in conservation and restoration efforts. By utilizing the BQI, we can make informed decisions to protect and restore estuarine ecosystems for the benefit of marine biodiversity and the health of our oceans.

A facultative mutualism facilitates European seagrass meadows

Coastal ecosystem functioning often hinges on habitat‐forming foundation species that engage in positive interactions (e.g. facilitation and mutualism) to reduce environmental stress. Seagrasses are important foundation species in coastal zones but are rapidly declining with losses typically linked to intensifying global change‐related environmental stress. There is growing evidence that loss or disruption of positive interactions can amplify coastal ecosystem degradation as it compromises its stress mitigating capacity. Multiple recent studies highlight that seagrass can engage in a facultative mutualistic relationship with lucinid bivalves that alleviate sulphide toxicity. So far, however, the generality of this mutualism, and how its strength and relative importance depend on environmental conditions, remains to be investigated. Here we study the importance of the seagrass‐lucinid mutualistic interaction on a continental‐scale using a field survey across Europe. We found that the lucinid bivalve Loripes orbiculatus is associated with the seagrasses Zostera noltii and Zostera marina across a large latitudinal range. At locations where the average minimum temperature was above 1 °C, L. orbiculatus was present in 79% of the Zostera meadows; whereas, it was absent below this temperature. At locations above this minimum temperature threshold, mud content was the second most important determinant explaining the presence or absence of L. orbiculatus. Further analyses suggest that the presence of the lucinids have a positive effect on seagrass biomass by mitigating sulphide stress. Finally, results of a structural equation model (SEM) support the existence of a mutualistic feedback between L. orbiculatus and Z. noltii. We argue that this seagrass‐lucinid mutualism should be more solidly integrated into management practices to improve seagrass ecosystem resilience to global change as well as the success of restoration efforts.

Identifying temporal dynamics in post‐release survival of a restored large ungulate

Abstract Wildlife translocation is an important conservation tool for restoring species and reducing global biodiversity decline; however, this practice is challenging for wildlife, and translocated individuals must adjust to their release landscapes for restoration success. The period following release is a vulnerable time for wildlife and determining when animals acclimate following translocation improves long‐term estimates of population dynamics and allows researchers to efficiently tailor translocation design and post‐release management to each population's needs. We evaluated demographic acclimation and investigated changes in post‐release survival of a population of 106 elk Cervus canadensis translocated to Missouri, USA, in 2011–2013 using generalized survival modelling. We defined the acclimation period as the duration of time prior to stabilization in mortality risk relative to time from release, and we evaluated acclimation duration from flexible plots of estimated mortality hazards across time. We simultaneously investigated factors contributing to post‐release survival and compared survival rates and mortality sources observed during acclimation and post‐acclimation periods. Elevated mortality risk for translocated elk spanned a 5‐month acclimation period following release, with an additional 1‐year period reflecting reduced, but still elevated, mortality hazards. Baseline hazards during the initial 5‐month acclimation period were approximately four times higher than the subsequent 4.4 years following release. Release cohort, but not age class or sex, was associated with post‐release mortality risk, and mortality sources within the acclimation period tended to be undetermined with greater frequency relative to mortalities occurring after the acclimation period. Our results highlight the utility of flexible modelling approaches to evaluate dynamic post‐release responses of translocated populations. Translocated elk demonstrated a pronounced demographic acclimation period that spanned 5 months following release. Changes in mortality sources and the timing of stabilization in mortality hazards suggest that demographic acclimation in translocated elk was associated with adjustments in physiological stress and movement rates which stabilized over a similar post‐release duration. Improving post‐release monitoring and assessment of restored populations by evaluating temporal dynamics of manifold biological and ecological responses as translocated animals acclimate to their new landscapes is vital to successful restoration efforts.

Adapting ecosystem restoration for sustainable development in a changing world

Adapting ecosystem restoration for sustainable development in a changing world

Rehabilitation of eroded trails and gullies on quartzite rock outcrops with native species in a high-altitude grassland

The quartzite rock outcrops and the native vegetation of grasslands located at the Serra da Calçada Mountain in Minas Gerais State (Brazil) have been severely degraded by extreme sports activities such as motocross and off-road vehicles, greatly damaging the abundant headwaters. The main consequences thereof were hilly and gully erosion processes with soil loss and the deviation of the water from its original paths. However, currently, there is no report of successful restoration efforts in severely eroded outcrops in Brazilian high-altitude grasslands (campo rupestre). Through the Universal Soil Loss Equation (USLE), we found a high general erosion rate in the study site (669.91 t·ha−1·year−1), and the specific soil loss provoked by off-road vehicles on trails was significantly greater (49 m3 per 100 m2) than that caused by mountain bikes and trekking (5.8 m3 per 100 m2). We performed the physical reconstruction of eroded outcrops and surface water flow paths by allocating locally available quartzite rocks. These rocks were inoculated with different species of bryophytes and planted with native species under two treatments: un-inoculated and inoculated with arbuscular mycorrhizal fungi (AMF) spores of the Rhizophagus irregularis species. After 2 years, the bryophyte communities showed a similar pattern to the preserved site, and the AMF inoculation favoured plant establishment of most species, especially of the Asteraceae, Cyperaceae, Fabaceae, Malpighiaceae, Orchidaceae and Poaceae families. The AMF also improved the soil fertility, highlighting soil P, SOM, CEC, NH4+-N as well as soil water content and water retention capacity. Poaceae family species showed an outstanding occupation, which was considered a functional indicator of rehabilitation success, functioning as a “hydraulic carpet” for water exportation, conduction and drainage across the outcrops. This study provides an eco-technology to restore severely eroded outcrops over headwaters using native species in the Brazilian high-altitude grasslands.

An eco‐evolutionary perspective on the humpty‐dumpty effect and community restoration

In recent decades, anthropogenic and natural disturbances have increased in rate and intensity around the world, leaving few ecosystems unaffected. As a result of the interactions among these multiple disturbances, many biological communities now occur in a degraded state as collections of fragmented ecological pieces. Restoration strategies are traditionally driven by assumptions that a community or ecosystem can be restored back to a pre‐disturbance state through ecological remediation. Yet despite our best efforts, attempts to restore fragmented communities are often unsuccessful. One explanation, the humpty‐dumpty effect, suggests that once a community is disassembled, it is difficult to reassemble it even in the presence of all the original pieces. This hypothesis, while potentially useful, often fails to incorporate the multitude of other critical mechanisms that affect our abilities to put fragmented communities back together. Here, we extend the original humpty‐dumpty analogy to incorporate eco‐evolutionary changes that can hinder successful restoration. A systematic literature review uncovered few studies that have explicitly considered how the original humpty‐dumpty effect has affected restoration success in the 30 years since its inception. Using case studies, we demonstrate how the application of our extended eco‐evolutionary humpty‐dumpty framework may determine the success of restoration actions via ecological and evolutionary changes in fragments of communities. Lastly, given continued anthropogenic disturbances and projected climatic changes, we make five recommendations to facilitate more successful restoration efforts given our revised eco‐evolutionary humpty‐dumpty effects framework. These guidelines, combined with clearly defined management goals are aimed at both keeping ecological communities as intact as possible while ensuring that future ecosystem restorations might more successfully put the ecological community pieces back together.

Fine-scale Weather Patterns Drive Reproductive Success in the Brown Pelican

In the northern Gulf of Mexico, island restoration and creation have been used to mitigate potential negative effects of anthropogenic and environmental stressors to breeding seabirds. The long-term success of such projects can be enhanced when data are available to elucidate how site-specific and larger-scale factors may contribute to reproductive success. Nest-specific daily survival rate (DSR) of Eastern Brown Pelicans (Pelecanus occidentalis carolinensis) during incubation (i.e., pre-hatch; n = 245) and brood-rearing (i.e., post-hatch; n = 185) were measured at two breeding islands in the northern Gulf of Mexico USA in 2017 and 2018 in relation to macro- and micro- scale habitat and environmental measurements. DSR of nests during incubation ranged from 91-99%, and the DSR during brood-rearing exceeded 99% each year. Regional weather variables occurred in top-performing models more often and with more significance compared to microhabitat variables. Results suggest that reproductive success of Brown Pelicans may respond at least in part to weather factors that occur outside of the scope of habitat structure as it is typically incorporated into the restoration or creation of breeding habitat, indicating that climate conditions are likely an important factor in the success of restoration efforts.

Rewetting and Drainage of Nutrient-Poor Peatlands Indicated by Specific Bacterial Membrane Fatty Acids and a Repeated Sampling of Stable Isotopes (δ15N, δ13C)

Peatland degradation impairs soil functions such as carbon storage and the existence of biodiversity hotspots. Therefore, and in view of the ongoing climate change, an efficient method of evaluating peatland hydrology and the success of restoration efforts is needed. To understand the role of microbial groups in biogeochemical cycling, gaseous loss and isotopic fractionation that lead to specific isotopic depth patterns (δ13C, δ15N), we integrated previously published stable isotope data with a membrane fatty acid (mFA) analysis related to various microbial groups that are known to be common in peatlands. We performed two sampling campaigns to verify the observed stable isotope depth trends in nutrient-poor peatlands in Northern Europe. Cores were taken from adjacent drained (or rewetted) and undrained sites. Fungal-derived mFA abundance was highest in the uppermost part of the drained layer. We found increasing bacterial-derived mFA concentrations with depth peaking in the middle of the drained layers, which correlates with a δ15N peak of bulk material. The results support our hypothesis that changing peatland hydrology induce a shift in microbial community and metabolism processes and is therefore also imprinted in stable isotope values. Under waterlogged conditions overall levels of microbial-derived mFAs were generally low. Drained layers showed simultaneous changes in microbial abundance and composition and depth trends in stable isotope bulk values. Bacteria, particularly acidobacteria, can be expected to dominate increased denitrification with low oxygen saturation accompanied by increased δ15N bulk values in the remaining substrate. Interestingly, cores from recent rewetted peatlands show no depth trend of δ15N in the layers grown under rewetting conditions; this is congruent with relatively low concentrations of microbial-derived mFAs. Hence, we conclude that stable isotopes, especially δ15N values, reflect changing microbial metabolic processes, which differ between drained and undrained - and especially also for recent rewetted–peatlands. As today stable isotope measurements are routine measurements, these findings enable us to get cost- and time efficient reliable information of drainage and restoration success.

Environmental DNA Assessment Reveals Restoration Success for Mudpuppies (Necturus maculosus)

Mudpuppies (Necturus maculosus) are secretive, fully aquatic salamanders with a range that spans much of the eastern United States and Canada including the Great Lakes region. Although this species was once abundant, there have been widespread declines due to habitat loss and modification, pollution, lampricide use, and overcollection. We compared environmental DNA (eDNA) and trapping surveys conducted from 2014 to 2016 to determine Mudpuppy occupancy along the St. Clair-Detroit River System, where this indicator species could be a gauge for success of ongoing restoration. Mudpuppy eDNA was detected at all sites with positive trapping records, as well as one site where individuals have not been trapped previously. Sites with shoreline restoration had the highest occupancy estimates, whereas deep-water restoration did not affect Mudpuppy occupancy. Additionally, eDNA surveys resulted in higher detection probability than setline and minnow trap survey methods, illustrating the benefit of using eDNA to detect secretive species. This study demonstrates the success of restoration efforts in increasing the occupancy of an indicator species and can be used as a template for other restoration initiatives.

Hydrodynamic habitat thresholds for mangrove vegetation on the shorelines of a microtidal estuarine lagoon

Although understanding the requisite hydrodynamic habitat for mangrove vegetation is vital for successful restoration efforts, few studies have quantitatively assessed the in-situ tolerance of mangroves to relevant physical forcing mechanisms. In this work, hydrodynamic thresholds for the persistence of mangrove vegetation (Rhizophora mangle, Avicennia germinans, and Laguncularia racemosa) are assessed using a hindcast wind-wave model coupled with a high-resolution shoreline survey, with analysis including 383 km of shoreline located in a microtidal estuary along the Atlantic coast of Florida (north Indian River Lagoon, USA). Observed mangrove distribution patterns were most strongly correlated with the modelled wave climate (p < 0.001) and measured intertidal slope (So; p < 0.001), and mangrove presence probabilities were maximized for sample sites characterized by low slopes (So < 0.5) and weakly energetic waves (80th percentile wave height: H80 < 2.5 cm). Critical wave thresholds (mean ± 95% confidence interval) of H50=4.2 ± 0.4cm and H80 = 8.0 ± 0.5cm were estimated for 50th and 80th percentile wave heights, respectively, representing the wave climate limits above which mangrove presence probabilities fall below 50%. Low intertidal slopes were observed to enhance mangrove wave tolerance (So≅0; H80 = 9 cm) while high slopes led to dramatic reductions in threshold wave heights (So≅1; H80 = 4 cm). These results have important implications for future restoration efforts, providing the first available quantitative wave thresholds for mangrove habitat suitability.

Switch of fungal to bacterial degradation in natural, drained and rewetted oligotrophic peatlands reflected in &amp;lt;i&amp;gt;δ&amp;lt;/i&amp;gt;&amp;lt;sup&amp;gt;15&amp;lt;/sup&amp;gt;N and fatty acid composition

Abstract. For centuries European peatlands have been degrading along with drainage, land use and climate changes. Increasing pressure on peatland ecosystems calls for a more cost-efficient method to indicate the current state of peatlands and the success of restoration efforts. Metabolic pathways in peatland soils are imprinted in stable isotope compositions due to differences in microorganism communities and their metabolic pathways. Therefore, we hypothesize that depth profiles of nitrogen stable isotope values provide a promising opportunity to detect peatland decomposition or restoration. We studied five peatlands, namely Degerö Stormyr (northern Sweden), Lakkasuo (central Finland) and three mires in the Black Forest (southern Germany). At all locations, cores were taken from adjacent drained (or rewetted) and natural sites to identify δ15N trends that could indicate changes due to drainage and restoration. At all drained (and rewetted) sites we found a distinct peak (“turning point”) of the δ15N values in the center of the drained horizon. We did a fatty acids (FAs) analysis to link our results to microbial community composition. As markers, we distinguished between one fungal-derived FA (C18:2ω9c) and four bacterial-derived FAs. For bacteria, we looked for one general bacterial-derived FA (C14:0), two FAs for gram-positive bacteria (i-C15:0; a-C15:0), and one FA for gram-negative bacteria (C16:1ω9c). In accordance with other studies, our results suggest that fungi dominate the microbial metabolism in the upper aerobic peat horizon. This is reflected by depleted δ15N values. Moving downwards, the drained horizon conditions slowly switch to oxygen limitation. Consequently, fungal-derived FAs decrease whereas bacterial-derived FAs rise. The highest diversity of microbial-derived FAs is indicated by the δ15N turning point. Below the δ15N turning point, oxygen is increasingly limited and concentrations of all microbial-derived FAs are decreasing down to the onset of the permanently waterlogged anaerobic horizon. Peatland cores with restoration successes again show, above the formerly drained horizon, no depth trend of the isotopic values. Hence, we conclude that δ15N stable isotope values reflect microbial community composition, which differs between drained and natural peatlands.

The use of spatially patterned methods for vegetation restoration and management across systems

Widespread degradation of natural lands has created an urgent need for restoration. However, the high cost of conventional techniques limits the extent and success of restoration efforts. As a result, practitioners have developed new cost‐effective techniques. Spatially patterned restoration methods, where established clusters of plant species serve as propagule sources across a broad target area, have been proposed as practical restoration techniques. The spatial patterning is expected to reduce initial costs and provide ecological benefits such as increasing habitat heterogeneity. Over the past three decades, multiple spatially patterned restoration methods have emerged around the globe; however, it is unclear whether applications and theoretical foundations have been connected across methods. We conducted a literature review and bibliometric network analyses to (1) examine patterns in focal study systems, cost‐effectiveness, and ecological outcomes for spatially patterned restoration methods and (2) analyze connectivity among the bodies of literature associated with common spatially patterned restoration methods to identify knowledge gaps and synergies. We found the three most commonly studied methods are applied nucleation, slot seeding, and strip seeding. Applied nucleation studies mainly occurred in tropical forests and emphasized plant diversity and seed‐dispersing animal visitation. Slot‐seeding and strip‐seeding studies both primarily occurred in temperate grasslands and emphasized plant establishment and production. Applied nucleation and slot‐seeding approaches had distinct theoretical bases, as evidenced by patterns in reference citation, while strip‐seeding approaches did not draw from a unified body of literature. We discuss the need for full economic analyses and theoretical links between the different methods.

Food web properties vary with climate and land use in South African streams

Abstract Land use intensification and climate change are two prominent drivers of variation in biological communities. However, we know very little about how these two potential environmental stressors interact. Here we use a stable isotope approach to quantify how animal communities respond to urban and agriculture land use, and to latitudinal variation in climate (rainfall and temperature), in 29 streams across South Africa. Community structure was shaped by both land use and climatic factors. The taxonomic diversity of invertebrates was best explained by an independent negative effect of urbanization, while abundance declined in summer. However, we could not use our variables to predict fish diversity (suggesting that other factors may be more important). Both trophic functional diversity (quantifed using isotopic richness) and food chain length declined with increasing temperature. Functional redundancy (quantifed using isotopic uniqueness) in the invertebrate community was high in wet areas, and a synergistic interaction with urbanization caused the lowest values in dry urban regions. There was an additive effect of agriculture and rainfall on abundance‐weighted vertebrate functional diversity (quantified using isotopic dispersion), with the former causing a decline in dispersion, with this partially compensated for by high rainfall. In most cases, we found that a single dominant driver (either climate or land use) explained variation between streams. We only found two incidences of combined effects improving the model, one of which was amplified (i.e. the drivers combined to cause an effect larger than the sum of their independent effects), indicating that management should first focus on mitigating the dominant stressor in stream ecosystems for successful restoration efforts. Overall, our study indicates subtle food web responses to multiple drivers of change, only identified by using functional isotope metrics—these are a useful tool for a whole‐systems biology understanding of global change. A free Plain Language Summary can be found within the Supporting Information of this article.

Cascading social-ecological costs and benefits triggered by a recovering keystone predator.

Predator recovery often leads to ecosystem change that can trigger conflicts with more recently established human activities. In the eastern North Pacific, recovering sea otters are transforming coastal systems by reducing populations of benthic invertebrates and releasing kelp forests from grazing pressure. These changes threaten established shellfish fisheries and modify a variety of other ecosystem services. The diverse social and economic consequences of this trophic cascade are unknown, particularly across large regions. We developed and applied a trophic model to predict these impacts on four ecosystem services. Results suggest that sea otter presence yields 37% more total ecosystem biomass annually, increasing the value of finfish [+9.4 million Canadian dollars (CA$)], carbon sequestration (+2.2 million CA$), and ecotourism (+42.0 million CA$). To the extent that these benefits are realized, they will exceed the annual loss to invertebrate fisheries (-$7.3 million CA$). Recovery of keystone predators thus not only restores ecosystems but can also affect a range of social, economic, and ecological benefits for associated communities.

The benefits of ecosystem restoration

Ecological Economics Human activities have fundamentally altered many ecosystems. Recent successful restoration efforts have led to healthier ecosystems, but this has led to a disruption in economies dependent on the altered state of the system. One of the best-known trophic cascades is the sea otter–kelp forest system, wherein recovery of once extirpated sea otters is bringing back biodiverse and healthy kelp forests but reducing the abundance of harvested shellfish. Gregr et al. looked at the costs and benefits of this shift and found that for key trade-offs, the value of kelp forest–associated features such as tourism, fin fish fisheries, and carbon capture outweighed the losses to economies (see the Perspective by Estes and Carswell). Thus, ecosystem recovery can benefit both ecosystems and economies. Science , this issue p. [1243][1]; see also p. [1178][2] [1]: /lookup/doi/10.1126/science.aay5342 [2]: /lookup/doi/10.1126/science.abc7060

The role of historical sources in the restoration of Long Swamp, Discovery Bay, Victoria

Inspired by the success of restoration efforts in the adjacent Piccaninnie Ponds Karst Wetlands Ramsar site, the local community was anxious for progress to address observed changes to the hydrology of Long Swamp, near Nelson, Victoria. Uncertainty about the original character and condition of the wetland system required deep exploration of a vast range of historical reference material. This is a story of how disparate sources of historical information can complement modern scientific methods, help resolve contentious issues and contribute to refining reference ecosystem models to improve restoration outcomes.Long Swamp from Oxbow Lake (A) to Lake Momboeng (B), showing the Glenelg River Mouth (1) and ocean outlet locations at White Sands (2) and Nobles Rocks (3). The hypothesised original main direction of surface flows was from east to west (from B to A). N = north.image

Tree water use strategies and soil type determine growth responses to biochar and compost organic amendments

Background and aimsOrganic matter is often used as an amendment to attempt restoration of degraded soils to improve tree establishment and growth. One key aim is to increase plant available water in the soil profile. The texture of the soil, the type of organic amendment (e.g. compost or biochar), and the native environment of the tree (mesic or xeric) will impact how successful restoration efforts are. We aimed to determine whether compost and biochar amendments, either individually or in combination, would improve plant available water (PAW) in both clay and sand soils. We then aimed to measure whether changes in PAW would translate into increased water use and plant growth of both mesic (Corymbia maculata) or xeric (Eucalyptus torquata) tree species under well-watered (WW) or water deficit (WD) conditions. MethodsClay and sand soils were amended with compost, biochar or a compost and biochar mix, whilst unamended soils acted as controls. Soil moisture characteristics of the soil mixes were determined with samples in the laboratory. Fifteen replicate pots (6 l) of each soil treatment were then planted with either mesic and xeric tree species. All pots and trees were subjected to either a WW or WD irrigation regime for 7 weeks. WD irrigation was a set percentage of the daily WW evapotranspiration (ET). ET was calculated as total pot mass one hour after irrigation (to allow for drainage) minus the total pre-dawn pot mass of the subsequent day. The tree biomass, biomass partitioning, ET, and tree water status were measured throughout the experiment to understand growth and stress responses. Key resultsThe xeric tree species (E. torquata) grown in sand soil had a significant increase in growth with all three OM amendments but did not when grown in clay soil. In contrast, we found no significant growth response for the mesic tree species (C. maculata) when grown in either clay or sand amended with any OM treatment. The ET of the xeric tree species was greater for all the OM amended soils for both WW and WD plants in the sand soil. ConclusionsThis study shows that OM amendments may improve the soil water properties of sand-based soils which in turn can increase the growth of xeric tree species. However, more expensive organic amendments may not be necessary, nor mixing of OM types, as we found no tree growth differences amongst the three different OM treatments.