Restoration Sites Research Articles

Disease assessment in 'coral gardening' nurseries in the Maldives and implications for coral restoration success.

Coral diseases are an increasing threat to continuously degrading reefs as disease abundance and virulence are expected to increase in the future. Active conservation measures, specifically coral restoration projects, are increasingly being implemented worldwide. Yet little is known about the implications of disease occurrence in a restoration context. This study describes white syndrome pathogenesis in 2 coral genera, farmed in 2 mid-water rope nurseries located in a reef and a lagoon habitat in the Maldives. Over a 112 d monitoring period, disease metrics were obtained from 336 Pocillopora and 96 Acropora fragments to assess the impacts of unmitigated disease progression in coral nurseries. Disease had low prevalence (2.2%) and incidence (0.007) in reef-farmed Pocillopora, but survival (91%) was significantly reduced in comparison with the unaffected lagoon-farmed Pocillopora (99%). In contrast, lagoon-farmed Acropora showed high disease prevalence (78.5%) and incidence (0.064), and a lower survival (79%) than disease-unaffected reef-farmed Acropora (98%). These findings had distinct implications for coral gardening success. While Pocillopora was considered suitable for outplanting, especially since subsequent mitigation interventions were successful, the diseased, lagoon-reared Acropora posed a potential risk to the restoration site and was unsuitable for outplanting following 1 yr of farming effort. Our findings demonstrate that unmitigated diseases can cause major setbacks to restoration success. Coral gardening projects are likely to be particularly susceptible; therefore, disease monitoring and risk management are imperative. Since there is currently a lack of available diagnostic and mitigative tools, this study aims to provide case study data for restoration practitioners.

A data-driven approach to traditional village colors: K-Means clustering of online images

ABSTRACT This study aims to quantify the color characteristics of traditional villages, explore the key aspects of color that attract tourist attention, and propose solutions to enhance the readability and legibility of these villages. The findings are intended to provide practical guidance for the restoration and use of village colors. The research focuses on how tourists perceive the color characteristics of traditional villages. The objective is to conduct color clustering analysis to identify the composition and characteristics of village colors, and further analyze the underlying causes to offer suggestions for optimization and enhancement. It employs a methodology based on urban imagery theory, using clustering and secondary extraction of color data from online images. The results reveal distinct contrasts and harmonies in the colors of the five elements providing a basis for improving spatial readability and visual guidance. These findings not only offer practical design references for optimizing traditional village colors but also provide valuable insights for the protection and restoration of other traditional sites. In particular, the contrast between the colors of boundaries and landmarks can enhance visual recognition, while the complementary color designs of paths and boundaries can improve spatial readability, contributing to the sustainable development of traditional villages.

A Study on the Water Management Knowledge of Traditional Villages from the Perspective of Stormwater Resilience—A Case Study of Changqi Ancient Village in Guangdong, China

With the advancement of resilience concepts, enhancing resilience capacity has become an effective approach to addressing rainwater and flooding issues. Most rural planning and construction efforts adopt urban planning models from economically developed regions, often leading to surface hardening, which subsequently causes drainage difficulties and severe surface water accumulation during the rainy season. In contrast, traditional Lingnan villages, exemplified by Guangdong’s Changqi Ancient Village, continue to function normally in flood-prone areas, suggesting that their water management knowledge merits investigation. Previous research on rainwater management in traditional Chinese villages has predominantly been qualitative, lacking scientific data support. This study employs an eco-social resilience perspective, combining field surveys and interviews with villagers, and utilizes the SWMM (Storm Water Management Model) software to conduct both qualitative and quantitative analyses of Changqi Ancient Village. The findings reveal the following: (1) The SWMM effectively quantifies rainwater and flood management in traditional villages. (2) From an ecological resilience perspective, the village’s geographical location is crucial. The topography, along with a rainwater regulation system comprising rivers, ponds, ditches, and permeable pavements, significantly influences the village’s drainage performance. (3) From a social resilience perspective, community participation is vital to the long-term stable development of traditional villages. This includes post-disaster collective fundraising by villagers for the restoration of rainwater and flood management facilities, the formulation of village regulations, and the construction and restoration of spiritual sites. (4) From an eco-social resilience perspective, the eco-social resilience system exhibits adaptive cyclical characteristics, where the geographical environment and the local economy significantly shape the ecological spatial patterns of Changqi, while positive interaction between nature and human society ensures the system’s dynamic equilibrium.

Measuring fisheries outcomes from coastal wetland restoration: a review and meta‐analysis

Coastal wetlands, including saltmarshes, mangrove forests, and seagrass meadows, can support fisheries by providing habitat and exporting food and nutrients to adjacent or distant ecosystems. However, there is insufficient understanding about the extent to which wetland restoration can benefit fishery species. Here, we report qualitative and quantitative reviews of literature to evaluate the approaches used to measure or estimate fisheries outcomes of coastal wetland restoration and test for the effects of restoration on fisheries outcomes. Most studies focused on saltmarshes and mangroves, with fewer studies focussing on seagrasses. We found that effects of wetland restoration on fish populations have mainly been assessed for species that reside in coastal wetlands for at least part of their life cycle, while few studies have tested effects on fish populations via trophic subsidies. Moreover, few studies have directly assessed the effects of restoration on fisheries production. Instead, most studies have measured abundances of individual species at restored sites and compared those to undisturbed and/or disturbed areas. Restored areas contained similar fish densities to undisturbed or disturbed areas; but few studies compared restored areas to both undisturbed and disturbed areas at the same time. Overall, we did not find consistent and robust evidence for fisheries outcomes from wetland restoration projects because (1) there were not many studies, (2) the studies reported substantial variability in outcomes, and (3) the density of fish measured at a restoration site is not an accurate measure of the total fisheries benefit as adult fishes do not always reside in the restored habitat.

Evaluation of soil properties and bulk δ15N to assess decadal changes in floodplain denitrification following restoration

Stream and floodplain restoration is a popular billion‐dollar industry in the United States, with many restorations being conducted to satisfy water pollution regulations and nutrient reduction goals. The long‐term efficacy of these restorations is, however, not well studied, and key soil metrics that can be used for performance assessments have not been developed. We evaluated a chronosequence of 12 restoration sites spanning an age range of 0–22 years to assess changes in denitrification rates and associated soil parameters. Restored versus unrestored reaches were compared for denitrification rate and functional gene nosZ, bulk soil δ15N, soil organic carbon (SOC), soil organic matter (SOM), bulk density, and soil moisture. Denitrification, SOM, SOC, and soil moisture were all found to increase with site age at restored sites, with the largest increase for the 10–22 age category. Bulk density decreased with time, with a significant decrease in restored floodplain soils. Bulk soil δ15N was highest immediately after restoration, decreased with restoration age, and was not positively correlated with denitrification. This may reduce its potential as a proxy for denitrification. Overall, this study reveals that selected soil metrics (SOC, SOM, soil moisture, and bulk density) could serve as a valuable proxy for denitrification and could help assess the denitrification effectiveness of floodplain restorations at the decadal time scales. Ideally, the soil metrics should be combined with other short‐term assessment measures, such as those for stream and groundwaters, for a robust performance assessment of restored floodplains.

Herbivory can reduce perennial grass seedling survival, but temperature and cumulative precipitation are more important predictors in the first growing season

Successful establishment of desired species during restoration is challenging in drylands. Much research has focused on the importance of the critical life stages such as germination and emergence, but factors influencing survival through the seedling stages of perennial grasses may be equally important. We asked whether seedling defoliation by insects and/or mammals could cause restoration failure. We quantified the degree of defoliation on seedlings of common perennial grass species at 46 restoration sites throughout Oregon, Idaho, and Nevada, and calculated survival probabilities during the first growing season after planting. At each site, we excluded small mammals and insects for 6 weeks and compared defoliation and survival probabilities with seedlings in controls without exclusions. Seedlings were classified as either: large perennial grasses (LPG), primarily from the Triticeae tribe, or Bluegrasses (Poa spp.). Defoliation of LPG reduced seedling survival, but the effect was small compared to the influence of meteorological variables, such as precipitation and temperature. Based on bite patterns, most defoliation resulted from insects. Only a small percentage of vegetation was removed (36% of individuals were defoliated, mean = 13.2% vegetation removal). Defoliation of bluegrasses was less common than that of LPG seedlings, with only 16% experiencing defoliation, primarily from insects (mean = 4.3% vegetation removal). Some defoliation did occur within the exclusion treatments, but the effect of defoliation on seedling survival did not appear to interact with treatment. Based on the results of this study, seedling herbivory is unlikely to be a major factor in restoration failure in the Northern Great Basin.

Microbial Inoculants Modify the Functions of Resident Soil Microbes to Expedite the Field Restoration of the Abandoned Mine

ABSTRACTGlobal‐scale mining activities have had significant deleterious impacts on local ecosystems and the overall environment, which will necessitate robust restoration efforts. A practical approach includes combining microbial inoculants with the technology of external soil spray seeding. This approach holds the potential for sustainable abandoned mine site restoration by enhancing plant growth through the modulation of soil nutrients and microbial communities. Nonetheless, the detailed effects of microbial inoculants on specific aspects of soil microbial community functions and their complex interactions with plant growth remain underexplored, particularly in the context of restoration efforts. To bridge this gap, we performed a four‐year field study at an abandoned carbonate mine location, using metagenomic sequencing to evaluate the influence of microbial inoculants on soil microbial functionality. Our research revealed that introducing microbial inoculants greatly enhanced essential soil parameters and notably increased plant biomass. Additionally, these inoculants altered the functional gene makeup of the microbial community, significantly boosting the relative abundance of processes such as nitrogen fixation, nitrification, denitrification, assimilatory nitrate reduction (ANRA), dissimilatory nitrate reduction (DNRA), and organic phosphorus mineralization. Conversely, there was a decrease in the relative abundance of carbon degradation, phosphorus regulation, and transport processes. We observed strong correlations between the abundance of nitrogen and phosphorus cycles and plant biomass. Crucially, microbial inoculants affect plant biomass by initially altering soil properties and subsequently coordinating nitrogen and phosphorus cycles. These findings provide valuable insights into the role of microbial inoculants in mine site restoration and offer a theoretical foundation for their broader practical application.

Assessing Atlantic Kelp Forest Restoration Efforts in Southern Europe

Kelp forests are essential marine ecosystems increasingly compromised by human activities. Effective reforestation strategies are urgently needed, and the “green gravel” method is a viable tool already used in some European regions. This study aimed to assess the success of this method using the native Kelp species Laminaria ochroleuca on the Portuguese coastline. Cultures of green gravel were reared until the specimens reached a size of approximately 3 cm. The gravel was then deployed at selected sites in Peniche, Berlengas, and Cascais. Over an eight-month period, scientific scuba divers monitored the integration of Kelp, along with associated fish, invertebrate, and algae communities. Nutrient availability, temperature, water movement, substrate type, and Rugosity Index (RI) were also measured. The highest success rate was 12% in Consolação, with Elefante and Galos (Berlengas) reaching 7% and 4%, respectively. By the end of the monitoring period, Cascais had no remaining Kelp on green gravel. Present data suggest that higher success is dependent on less rugged and higher RI topography. Higher grazing pressure, rougher terrain, and unexpected sedimentation appear to be the main obstacles to deployment success. Solid knowledge (biologic and topographic) on the restoration site, starting restoration actions near already established Kelp forests, and significantly scaling up restoration efforts could substantially improve the success of the green gravel method in future reforestation campaigns.

Uncovering data gaps in biodiversity research within Brazilian Atlantic Forest restoration

Bringing together and synthesizing data from several primary studies and scales represents a powerful method for identifying patterns and gaps within forest restoration science. In this study, we employ a pioneer quantitative database‐driven review combined with spatial analysis to delineate research trends across biodiversity studies within the Brazilian Atlantic Forest (BAF). We gathered a total of 90 primary studies that met our inclusion criteria, collectively providing 822 observations (comparisons between restoration sites and reference forests) spanning restoration areas with ages ranging from 1 to 90 years old. Vascular plants and invertebrates dominated in terms of data availability, whereas soil microorganisms were the subject of limited inquiry. There is an evident disparity in the number of evidences for different forest types across regions, with mixed forest being underrepresented in relation to seasonal forest and dense forest (rainforest). On the contrary, we observed an even distribution of biodiversity outcomes across the age categories we defined for reference forests (i.e. secondary forest, secondary advanced, and old‐growth forest). Geospatial analysis revealed a concentration of research efforts within the southeastern region of the BAF. However, a significant research deficit remains for the northeast and south regions, crucial for comprehending biodiversity responses to restoration in environmental extremes. By integrating both qualitative and quantitative approaches, this framework review provides a roadmap for deepening our understanding of biodiversity responses to restoration in the BAF. Ultimately, it serves as a bridge between quantitative findings and nuanced contextual insights, guiding future research and similar studies across diverse ecosystems worldwide.

An analytical study of the tabia mortar from Lin Yimu’s tomb, Zhejiang, China

The Lin Yimu’s tomb in Zhejiang Province, China, is a significant Qing Dynasty tabia structure that, despite relatively good preservation, has suffered damage from weathering, necessitating urgent restoration. In this study, we conducted a comprehensive scientific analysis of archaeological samples from the tabia of Lin Yimu’s tomb, employing a range of analytical techniques including X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM/EDX), Fourier transform infrared spectroscopy (FTIR), chemical methods, and measurements of hardness and strength. Analytical results revealed that the main phases of the sample are calcite, quartz, illite/mica, feldspar, with a minor presence of Tung oil. The proportion of calcium carbonate is approximately 27%, and the ratio of earth to sand is 1:2, suggesting a raw material formula mass ratio of lime-earth-sand of 3:4:8. The surface hardness of the sample is measured at 293 ± 15 HL, with a compressive strength of 5.5 ± 0.2 MPa. The sand used in the raw material has a medium particle size of 250 μm, while earth particles are predominantly around 17 μm. The sample exhibits a porosity of 27.5%, with pore sizes concentrated at 95 nm. These findings contribute significantly to our understanding of Qing dynasty tomb construction technologies and provide a solid scientific basis for the restoration of such historical sites.

Microbial Inoculants Drive Changes in Soil and Plant Microbiomes and Improve Plant Functions in Abandoned Mine Restoration.

The application of microbial inoculants holds promise for the sustainable restoration of abandoned mine sites by affecting soil nutrients and microbial communities. However, the responses of plant microbial communities to microbial inoculants in mine restoration remain largely unknown. To bridge this knowledge gap, we conducted a 4-year field experiment at an abandoned carbonate mine site to assess the impacts of microbial inoculants on the soil-plant microbiome. Our findings revealed that microbial inoculants significantly changed roots, fine root bacterial and fungal communities. Further, no significant correlations were observed between the soil-plant nutrient content (Z-score) and microbial alpha diversity. However, a significantly positive correlation was found between the relative abundance of the keystone ecological cluster (Module #1) and soil-plant nutrient content. The application of microbial inoculants also increased complexity, albeit decreased stability of plant microbiome networks, alongside a reduction in stochastic assembly. Conversely, they decreased the complexity but increased the stability of soil microbiome networks, accompanied by an increase in stochastic assembly. Notably, the number of specifically enriched microbiome functional traits of roots and root nodules under the microbial inoculant treatments surpassed that of the control. In summary, our findings underscored the potential of microbial inoculants to enhance soil-plant functionality at abandoned mine restoration sites.

Forest restoration benefits common and rare wood-decomposing fungi with a delay

Decline in the amount of dead wood deteriorates habitats for saproxylic organisms globally. This could be compensated by restoration, but it is poorly understood how created dead wood corresponds to the habitat requirements of saproxylic species. Using a large-scale field experiment of 30 restoration sites across Finland, we studied the long-term (5–15 years) effects of dead wood creation on wood-decomposing fungi (polypores) in Norway spruce and Scots pine dominated forests. All studied conservation areas had been used for timber production prior to conservation. The average amount and diversity of woody debris was higher on the restoration treatments than on the non-restored controls. Altogether, 56 polypore species were recorded. Restoration treatments had 1.4 and 8 times more species and observations than controls. Eight red-listed polypore species were observed, six on the restored plots (four only from the created dead wood) and two on the controls. Species composition of polypore assemblages differed between the restoration and control treatments, as well as between the spruce- and pine-dominated forests. Following restoration, temporal changes in the polypore assemblages were clear but only partly related to dead wood creation. Unlike previous short-term studies, our results show that dead wood creation by felling and ring-barking trees benefits not only common but also indicator and red-listed polypore species; indeed, 15 years after restoration all red-listed species occurred on created dead wood. As some red-listed species occurred solely on naturally fallen trees five to ten years after restoration, created dead wood alone cannot substitute for natural dead wood.

Invertebrate-biased diet of burrowing owls in a newly-restored coastal grassland

Recovering biodiversity across trophic levels is a major challenge in restoration ecology. Specifically, predator population recovery depends on the timely re-establishment of their preferred prey species in restored habitats. Here, we evaluate potential dietary factors contributing to the loss of western burrowing owls (Athene cunicularia hypugaea (Bonaparte, 1825)) from a newly-restored coastal grassland. We examined owl pellets and found that burrowing owl diets were relatively low in vertebrate prey during their brief occupation of the restoration site (2.6% of prey items; found in 61.8% of sampled pellets). We suggest that preferred food limitation may have been one contributor to the loss of owls from the restoration site. These findings suggest the need to prioritise re-establishment of prey communities for effective long-term recovery of burrowing owls in restored landscapes.

Open ecosystems restoration: a global review shows biases and mismatches between theory and practice

Ecological restoration aims to recover the structure, biodiversity, and function of degraded ecosystems. However, open ecosystems have been largely overlooked in restoration, and the extent of theory‐based restoration is unclear. We systematically review papers on open ecosystems restoration from 2011 to 2021, examining publication trends with data on restored site age, size, indicators, and assessment frequency. We also explore the relationships between interventions, indicators, and ecological concepts. By analyzing 343 papers, we found that open ecosystems restoration is concentrated in North America and Europe, with nearly 75% of restored areas originating in these continents. Restored areas are small, assessed for a short duration, with a plethora of indicators and no establishment of clear control or reference areas for meaningful comparisons. Common open ecosystems restoration sites interventions involved trees and shrubs management, soil management, seeding, and transfer of plant material as the main interventions. From our analyzed papers, we found that 30% of them mentioned any ecological concepts, with community assembly and succession being the most mentioned ones. Furthermore, our exploratory analysis revealed no relationship between interventions, indicators, and ecological concepts, suggesting a widespread mismatch between theory and practice. As the Decade for Ecosystem Restoration unfolds, we call practitioners, researchers, and stakeholders working on open ecosystems to address challenges and curtail widespread biases. Despite the uniqueness of each restoration project, a clear, well‐planned design encompassing site‐specific variables and solid theoretical bases is expected to enhance restoration outcomes, optimizing costs and biodiversity gains.

Two Western Pacific Tabernaemontana Species Contrast in Biomass Allocation and Leaf Physiological Plasticity to Sun and Shade

The ability of plants to modify biomass allocation and leaf phenotypes to best utilize available resources has been heavily studied. No Tabernaemontana species have been included in this research agenda. Therefore, Tabernaemontana pandacaqui Poir. and Tabernaemontana rotensis (Kaneh.) B.C. Stone plants were subjected to 24% or 100% sunlight and various traits were determined to compare the relative level of plasticity. Midday net carbon dioxide assimilation was greater for T. rotensis in sun-grown plants, but greater for T. pandacaqui in shade-grown plants. Saturating light intensity and midday Fv/Fm were greater for T. rotensis in sun-grown plants, but did not differ between the species for shade-grown plants. Light compensation intensity was greater for T. rotensis than T. pandacaqui in both light treatments. Apparent quantum yield was greater for T. pandacaqui shade-grown plants but was similar for the two species in sun-grown plants. Greater relative root growth in full sun compared with shade was exhibited by T. rotensis but not by T. pandacaqui. These findings indicated that T. pandacaqui develops functional traits that improve performance in shade-grown plants, and T. rotensis develops facultative traits that enable performance in sun-grown plants. These insights into how T. pandacaqui and T. rotensis respond to sun and shade conditions add to the knowledge needed to inform the selection of niche conditions when using them in managed mixed forest plantings such as conservation and restoration sites.

Less hay collected at more dates: toward successful restoration of subtropical grasslands by hay transfer

Hay transfer is a promising method to restore temperate and subtropical grasslands, but its efficiency may depend on the harvesting timing and amount of hay used. We evaluated effects of harvest date (mid‐spring/November, early summer/December, and mid‐summer/February) and hay quantity (500 and 1000 g/m2) on vegetation cover, species richness, and species composition in an experimental study in subtropical southern Brazil for a period of 2 years. We transfer undried hay from a well‐conserved reference area onto a former grassland site degraded by pine plantations. Hay harvested during mid‐spring and early summer led to higher soil cover and species richness compared to the mid‐summer hay treatment in the first year of the experiment. A drought spell decreased vegetation cover in the second year following the hay transfer, with the mid‐spring hay treatment being the least affected. C3 grasses were more effectively introduced by mid‐spring and early summer hay, in contrast to C4 grasses that were better introduced by mid‐summer hay. Lower quantities of hay tended to lead to higher cover and species richness for all harvest dates. Freshly cut undried hay can be an effective way to reintroduce native species in degraded subtropical grasslands. We conclude that timing of hay collection and the amount of hay used influence vegetation cover and species composition at the restoration site and that multiple harvest dates increase restoration success. The drought in the second year of the experiment illustrates the need to consider the possibility of adverse climatic conditions in restoration planning.

A flexible data‐driven approach to co‐producing drought vulnerability assessments

AbstractIntensifying weather events are key characteristics of climate change that are fundamentally changing ecological disturbance regimes. Intensifying drought is a particular threat to species, ecosystems, and ecosystem services worldwide. Proactive drought adaptation measures are acutely needed, but without a better understanding of drought vulnerability at the appropriate scale and geography, such measures may not be effective, or even anticipated as potential options. A recent conceptual framework for ecological drought aligns a holistic suite of potential drivers with the key components of climate change vulnerability (exposure, sensitivity, and adaptive capacity). We leverage the ecological drought framework and components of vulnerability to introduce a six‐step process for developing a drought vulnerability assessment (DVA) that (1) is place‐based and avoids mismatches between assessment geography and management action, (2) uses existing empirical datasets and leverages machine learning techniques and remotely sensed data from a recent drought, (3) emphasizes the inclusion of stakeholders and the importance of data visualization and science communication, and (4) is flexible and adaptable to a wide range of planning contexts. We illustrate the DVA process with a case study for forested watersheds in the Missouri Headwaters (MH), Montana, USA, that is focused on the impact of an early 2000s drought event on forest health. We show how the DVA provides insights on drought vulnerability that are helpful starting points for co‐developing region‐specific management actions to prepare for the next drought, including strategies to enhance ecologically available water, reduce competition for water, promote ecosystem persistence under drought conditions, and prioritize sites for forest restoration, transition, or protection. The work described here provides a model for developing a DVA in other places that, when used in a participatory adaptation planning process, supports the implementation of effective adaptation strategies.

Using Empirical Performance Data to Source Bluebunch and Snake River Wheatgrass Plant Materials to Restoration Sites in the Eastern Great Basin, USA.

To infer adaptation of plant material, restoration practitioners often consider only surrogate geographic or climatic information. However, empirical biomass data could assist in deciding what material to use where. To test this approach, we transplanted seven bluebunch wheatgrass (BBWG; Pseudoroegneria spicata) and five Snake River wheatgrass (SRWG; Elymus wawawaiensis) populations to three sites ranging from low to high precipitation (LPPT, MPPT, and HPPT). We measured establishment-year (2011) biomass at all sites and 2012-16 biomass at MPPT and HPPT. When data were standardized by site, P-7 and Anatone produced the mostBBWG biomass across sites and Wahluke the least in both 2011 and 2012-16, while E-58X produced the most SRWG biomass and Secar and E-49X the least in 2011 and 2012-16, respectively. Among BBWG populations in 2011, relative performance of P-7 (G6 generation) and Goldar increased and Whitmar decreased at wetter sites, while Columbia was stable (high) and Wahluke was stable (low) over sites. Among SRWG populations in 2011, Secar, Secar78, and E-58X increased at drier sites and Discovery at wetter sites. However, once established, populations of both species were much more similar for trend. In 2012-16, trend somewhat increased for five BBWG populations from MPPT to HPPT, was stable for Wahluke, but declined for Columbia, while all five SRWG populations declined at HPPT. These results suggest that, once established, BBWG is mostly stable across sites, while SRWG is less adapted to wetter sites. In 2012-16, BBWG populations originating at drier (or wetter) sites mostly performed relatively better at MPPT (or HPPT), suggesting adaptation to site. However, in the establishment year (2011), this relationship did not hold, suggesting seedling vigor and immature growth rate play a stronger role than precipitation at the site of origin.

Passive revegetation limited by seed availability in a salt marsh sediment addition site

Many approaches to restoring salt marsh habitats assume flora will naturally colonize the restoration site following the reinstatement of tidal hydrology that is appropriate for halophytes. However, this passive strategy can fail to meet restoration targets because of unfavorable site conditions and/or limited propagule dispersal. This study analyzes propagule availability in a restored southern California salt marsh that experienced slow passive revegetation following sediment addition to combat subsidence‐driven habitat loss. We performed a seedling emergence experiment to assess the quantity and species composition of viable halophyte seeds in the restoration site compared to nearby established salt marsh habitat. Additionally, we irrigated seed bank samples with freshwater or saltwater to test the effects of restoration site salinity conditions on seedling emergence and survival. Due to the proximity of the restoration site to seed sources, we expected to find ample seeds within its seed bank. However, only two seedlings emerged from restoration site seed bank samples (collected over 1.18 m2 of soil surface area), compared to an average of 44.33 seedlings from control site samples. Control site samples receiving saltwater irrigation had similar quantities of seedlings emerge, but seedlings in salt water had a reduced survival rate compared to seedlings in the freshwater treatment. Overall, these results suggest that passive restoration should be paired with techniques that retain seeds, such as increasing the topographic complexity of the restoration site. However, in scenarios where salinity or elevation may limit seedling recruitment, active planting should be considered to speed restoration trajectories.

PHOTO-REACTIVE ACRYLIC-ALKYD COMPOSITION WITH BIOCIDE ADDITIVE FOR WOOD PROTECTION COATING DEVELOPMENT

Introduction. The study of photo-reactive varnishes can serve as a basis for choosing alternatives in the restoration and preservation of historical and cultural heritage sites. Purpose of the study: The study aimed to explore the possibility of using photoreactive acrylic-alkyd composition with biocide additive as a paint and varnish material in construction as well as restoration and preservation. Methods. The possibility of obtaining protective thick-layer coatings from the proposed compositions with a thickness up to 80 μm without compromising polymerization efficiency in the layer was demonstrated by express Raman spectroscopy. Results. The coatings obtained by UV-curing from the composition with vinylated alkyd oligomers were tested to analyze vapor permeability, hardness, and hydrophobicity. The resistance of the specimens coated with the developed compounds against a mixture of mold fungi was studied. Aspergillus, Chaetomium, Trichoderma and Penicillium fungi were used as strains of micromycetes as those most infesting the open surfaces of timber. The effectiveness of biocide additive in the amount of 0.24 wt % is shown. The developed photo-reactive varnishes make it possible to form a finished wood coating within 1–2 minutes.