Ecosystem Changes Research Articles

The morphological variability and photosynthetic activity of the epigeic mosses in the forest ecosystems depending on the ecological locality conditions

The peculiarities of morphological variability and photosynthetic activity of the dominant epigeic mosses Polytrichastrum formosum, Plagiomnium affine and Atrichum undulatum depending on microclimatic conditions and the degree of anthropogenic changes in forest ecosystems were investigated. The morphological variability of mossy turfs in different ecological conditions of forest ecosystems was established, in particular, the influence of the level of humidity and the intensity of light on the morphometric parameters of mosses was revealed. The shoots and leaves of the studied mosses from the felling area were smaller and the density of turfs was higher compared to other localities. It was determined that a decrease in shoot height, leaf size, increase in leafiness and shoot density contributed to the preservation of water balance within the moss turf and the upper layer of the substrate. The dependence of the photosynthetic intensity of the leaves of dominant mosses on the moisture content of their turf and topsoil in the experimental plots of forest ecosystems was revealed. Changes in the functioning of the pigment system not only determined the photosynthetic activity of mosses in different localities, but also served as markers of their resistance to environmental conditions. The lowest intensity of CO2 assimilation was determined in the gametophyte of mosses in areas with recreational load. Probably, higher light intensity led to a violation of the water and temperature regime of plants, and thus to a decrease in their photosynthetic activity.

Roles of ecological and hydrological processes in the variability of carbon fluxes in a salt marsh of the Yangtze Estuary: Model simulations vs. measurements

Carbon exchange in coastal wetlands is a complex biochemical process regulated by a combination of meteorological, plant-soil, and hydrological factors. In the Yangtze Estuary, a process-based carbon flux model was developed to further elucidate the spatiotemporal dynamics of carbon fluxes of different marsh species and elevations, incorporating the roles of climatic, hydrological, and geographical factors. The model was validated based on measurements of CO2 and CH4 fluxes using the static chamber and eddy covariance methods. The results showed that the model reproduced well the time series of the net ecosystem change (NEE) and CH4 flux from diel to half-month scales. During tidal cycling, the ecosystem CO2 and CH4 fluxes were suppressed under inundation, and the magnitude of suppression was proportional to the water depth. The landform of the tidal flat determined the submerged height and duration, and the hydrological effects on carbon fluxes varied with elevation. The model also reasonably reflected the negative correlation between tidal height and salinity and carbon fluxes during the spring-neap cycle. Sensitivity tests revealed that temperature and tidal height were the two most critical factors affecting the carbon fluxes. Wavelet coherence analysis further indicated that temperature and tidal height explained most of the periodic variations in NEE at the diel scale. Specifically, temperature dominated CH4 emission dynamics in spring and winter, whereas tides replaced temperature as the dominant factor in summer. The temperature also exhibited a stronger coherent intensity at high elevations, whereas the influence of tides was greater in low-lying regions. This study emphasizes the associated effects of climatic, biological, and hydrological factors on the spatiotemporal heterogeneity of carbon fluxes in the coastal marshes. This coupled model is expected to be beneficial for estimating the carbon sequestration capacity in China's coastal salt marshes under global change conditions.

A DNA barcode reference of Asian ferns with expert-identified voucher specimens and DNA samples

Ferns belong to species-rich group of land plants, encompassing more than 11,000 extant species, and are crucial for reflecting terrestrial ecosystem changes. However, our understanding of their biodiversity hotspots, particularly in Southeast Asia, remains limited due to scarce genetic data. Despite harboring around one-third of the world’s fern species, less than 6% of Southeast Asian ferns have been DNA-sequenced. In this study, we addressed this gap by sequencing 1,496 voucher-referenced and expert-identified fern samples from (sub)tropical Asia, spanning Malaysia, the Philippines, Taiwan, and Vietnam, to retrieve their rbcL and trnL-F sequences. This DNA barcode collection of Asian ferns encompasses 956 species across 152 genera and 34 families, filling major gaps in fern biodiversity understanding and advancing research in systematics, phylogenetics, ecology and conservation. This dataset significantly expands the Fern Tree of Life to over 6,000 species, serving as a pivotal and global reference for worldwide barcoding identification of ferns.

Impact of extreme rainfall and flood events on harmful cyanobacterial communities and ecological safety in the Baiyangdian Lake Basin, China

Globally, climate change has intensified extreme rainfall events, leading to substantial hydrological changes in aquatic ecosystems. These changes, in turn, have increased the frequency of harmful algal blooms, particularly those of cyanobacteria. This study examines cyanobacterial community dynamics in the Baiyangdian Lake Basin, China, after heavy rainfall and flooding events. The aim was to clarify how such extreme hydrological events affect cyanobacterial populations in floodplain ecosystems and assess related ecological risks. The results demonstrated a significant increase in cyanobacterial diversity, exemplified by an increase of the Shannon diversity index from an average of 1.7 to 2.1 (p < 0.05). Following heavy rainfall and subsequent flooding, the average relative abundance of cyanobacteria in the microbial community increased from 7.59 % to 9.62 %, along a notable rise in the abundance of harmful cyanobacteria. The community structure exhibited notable differences after flooding, showing an increase in species richness, but a decrease in community tightness and clustering, as well as a reduction in niche overlap among harmful cyanobacteria. Environmental factors such as dissolved oxygen, water temperature, and pH were identified as crucial predictors of harmful cyanobacterial community differences and abundance variations resulting from flooding. These findings provide a critical framework for predicting ecological risks associated with the expansion of bloom-forming cyanobacteria in large shallow lake basins, particularly under intensified rainfall and flooding events. This insight is essential to anticipate potential ecological disruptions in sensitive aquatic ecosystems.

Climate change and disturbance interact to alter landscape reflectivity (albedo) in boreal forests across a large latitudinal gradient in Siberia

Boreal forests form the largest terrestrial biome globally. Climate change is expected to induce large changes in vegetation of high latitude ecosystems, but there is considerable uncertainty about where, when, and how those changes will occur. Such vegetation change produces major feedback to the climate system, including by modifying albedo (reflectivity). Our study used the LANDIS-II forest landscape model to project forest dynamics on four representative landscapes (1 M ha) for 280 years into the future under a range of climate scenarios across a broad latitudinal gradient in Siberia. The model estimated the albedo of the vegetation and any snow on each landscape grid-cell through time to quantify surface albedo change in response to climate change and disturbances. We found that the shortening of the snow-covered season (winter) decreased annual average albedo dramatically, and climate change facilitated the invasion of tundra by boreal trees in the northernmost landscape (reducing albedo in all seasons). However, in other landscapes, albedo increased in summer due to disturbances (fire, wind, insects, harvest), eliminating or reducing leaf area in the short-term, and in the mid-term by promoting more reflective forest types (deciduous, light conifers). This increased albedo was somewhat ephemeral and under climate change was overwhelmed by the shortening of the snow-covered season that greatly reduced albedo. We conclude that the primary driver of the overall reflectivity of boreal ecosystems is not vegetation, but rather, the length of the snow-covered season. Because climate change is likely to dramatically shorten the snow season, the concurrent reduction of albedo has the potential to act as a powerful positive feedback for climate change. Managing natural and anthropogenic disturbances may be the only tool with potential to mitigate the reduction of albedo by climate change in boreal ecosystems because management to encourage more reflective forest types has relatively small effect.

The meso- and bathypelagic cephalopod fauna of the Gully submarine canyon

Four midwater-trawl surveys were conducted during the summers of 2007–2009 and the spring of 2010 to document the meso- and bathypelagic biodiversity of the Gully canyon. These surveys collected 3871 cephalopods of at least 38 species in 22 families. The numerically dominant 13 species and one genus together comprised 90% of the total taken in standard survey sets. Each of those taxa uses the Gully in a different way, including within-family differences for the two cranchids and two mastigoteuthids. Oegopsids of note include Brachioteuthis beanii, which was the most abundant species in summer but entirely absent in March. The cirrate octopod Stauroteuthis syrtensis was collected in large numbers (n = 142) and a wide range of sizes (9–185 mm) suggesting it may complete its life cycle within the canyon. These results expand understanding of the trophic structure in the Gully and establish a baseline for future monitoring of ecosystem change.

Ecosystem-based fisheries management of crab fisheries in the Bering Sea and Aleutian Islands

We review ecosystem-based fisheries management (EBFM) of crab fisheries in the Bering Sea and Aleutian Islands (BSAI) and discuss considerations for future EBFM efforts under a rapidly changing climate. Specifically, we review governance frameworks, ecosystem policy, fishery ecosystem plans, catch accounting systems, trawl bycatch controls, trawl area closures and habitat protections, gear modifications, a Crab Rationalization Program, Ecosystem and Economic Status Reports, and Ecosystem and Socioeconomic Profiles. The strongest EBFM features of this management system include mechanisms to avoid overfishing, use of scientific knowledge, consideration of ecosystem connections, appropriate monitoring, acknowledging uncertainty, stakeholder involvement, and decisions that reflect societal choice. Some EBFM principles, such as the efficacy of gear and area closures and accounting for the dynamic nature of ecosystems have room for improvement. In spite of the large number of EBFM measures in place, three of the eight BSAI crab stocks with biomass estimates were below their minimum stock size thresholds, and thus classified as “overfished” in 2023. The lack of apparent correspondence between implemented EBFM actions and crab stock trends may indicate that environmentally driven sporadic recruitment, spikes in natural mortality, and stock range shifts mute favorable responses to EBFM actions or that outstanding critical EBFM measures have yet to be addressed. In the face of recent large-scale changes in the marine ecosystems of the BSAI and an outlook for greater changes in the future, it is increasingly important to routinely reevaluate interactions between crab, their ecosystems, fisheries and fishing communities.

The role of rehabilitating and restoration the green dam in managing the impact of invasive forest pests in Algeria

The rehabilitation of Algeria’s "Green Dam" project, a large-scale reforestation initiative, represents a key strategy for mitigating climate change, especially in semi-arid regions. This study, conducted between 2021 to 2024 in the semi-arid region of Djelfa (Algeria), evaluates the impact of defoliators in three different stands. Our findings reveal that infestation levels were significantly lower in mixed-species stands compared to monoculture stands, with monoculture plantations showing the highest infestation rates. Seasonal analysis revealed consistent stability in rehabilitated zones, with lower infestation indices throughout the year. The study highlights the role of species diversity in enhancing forest resilience to pest outbreaks, as mixed-species plantations naturally disrupt pest population dynamics and support healthier ecosystems. These results highlight the effectiveness of Green Dam’s rehabilitation in enhancing ecosystem health, increasing biodiversity, and reducing vulnerability to climate-induced disturbances, positioning it as a critical tool for ecological restoration and climate mitigation in northern Algeria. Furthermore, the project exemplifies a scientifically driven approach to combating desertification and climate change in semi-arid ecosystems. By integrating tritrophic analyses examining forest species, pest insects, and their antagonists—along with spatiotemporal monitoring, the study provides valuable insights into ecological interactions under changing climatic conditions. As expanding defoliators and xylophages pose increasing challenges, adaptive management strategies tailored to semi-arid regions are necessary. The rehabilitation of the Green Dam project emerges as a model for large-scale ecological restoration, combining reforestation efforts with scientific innovation to bolster ecosystem resilience, enhance sustainable land management, and address global issues such as biodiversity loss, desertification, and climate instability. Continued monitoring and adaptive management are essential to ensure the long-term success of reforested landscapes.

Cybercrime Management: The Role of Cybersecurity Education and Training

Leading technology companies such as Cisco, IBM, Fortinet, Broadcom, and the SANS Institute have responded to the growing threat of cybercrime by developing extensive cybersecurity tools and training programs. Examples of these tools include Cisco's Snort, IBM's QRadar, Fortinet's FortiGate, Broadcom's Symantec Endpoint Protection, and the SANS Institute's Metasploit. These tools are essential in a variety of industries, including financial services, healthcare, government, and manufacturing. They protect against cyberattacks, safeguard sensitive information, and ensure regulatory compliance; however, they present certain challenges such as complexity, cost, and the possibility of false positives. Future research should concentrate on creating flexible security frameworks, improving cybersecurity training, and extending automated incident response and predictive analytics as the digital ecosystem changes. These initiatives are essential for maintaining a step ahead of new threats and guaranteeing effective cybercrime management across all industries.

Shifting temperature-abundance relationship for Bering Sea walleye pollock consistent with northward expansion during exceptionally warm conditions

Rapid climate change in high-latitude ecosystems presents a challenge to fisheries management, as ecosystems are exposed to novel climate conditions that might expose non-stationary climate-biology relationships. Recently, the eastern Bering Sea has experienced a series of warm years outside the range of previous observations, resulting in shifting species distributions. We tested whether exceptionally warm temperatures from 2014-2019 revealed temporal non-stationarity in the relationship between temperature and the local abundances of walleye pollock Gadus chalcogrammus, an ecologically and commercially important species. Using survey catch per unit effort (CPUE) as a local abundance proxy, we detected a gradual shift through time in the local abundance-bottom temperature relationship, but little evidence for a sharp transition associated with marine heatwave conditions. Because pollock have expanded their range into novel habitats in the northeast Bering Sea (NEBS), we tested whether our models, parameterized for the southeast Bering Sea (SEBS), had predictive skill in the northeast. Our models were generally able to identify areas of high and low CPUE, though they under-predicted the magnitude of abundance observed in the northeast during the warm years. Spatial associations between pollock and other species differed between the warm period (2014-2019) and previous decades (1982-2013) for 3 of 9 species, providing mixed evidence for non-stationarity. These findings contrast with results showing sharp rather than gradual changes in climate-biology relationships associated with climate transitions in nearby ecosystems. The same processes that govern walleye pollock abundance and distribution appear to apply to both the SEBS, historically the core of their distribution, and the NEBS.

A multi-scale integrative approach to study the impact of a common pesticide, the dimethoate, on a mangrove fiddler crab Tubuca urvillei.

At land-sea interface, mangroves are likely to be exposed to pesticides due to agricultural run-offs. In Mayotte Island (Comoros archipelago, Mozambique Channel), dimethoate (DMT) is found in high concentrations in tomatoes, but no data confirm its presence in mangroves. We aimed at screening the presence of DMT in three mangroves of Mayotte at different levels (highest point above crops, village, upstream mangrove, downstream mangrove) and assessing the impact of DMT coupled with reduced salinity on mangrove crab physiology. To do so, we performed 24-h exposures at sublethal concentrations (10 and 100µg L-1) corresponding to 100 × and 1000 × the environmental standard (no data exist on environmental concentrations), in seawater (SW) and diluted SW (dSW). We exposed male fiddler crab Tubuca urvillei, one of the most common fiddler crabs living in mangrove areas regularly flooded and exposed to agricultural run-offs. Different physiological endpoints were considered: behaviour, acetylcholinesterase (AChE) activity, muscle energy metabolism, DNA oxidative damage and osmoregulatory capacity using hemolymph samples, posterior gills and claw muscle. We confirmed the presence of DMT in one mangrove and the effect of pesticide exposure at the different endpoints. Changes in behavioural and physiological parameters highlighted in this study could warn us of recent pesticide use upstream and help us understand past or future community-level changes in mangrove ecosystems affected by pesticide inputs.

Study the Dynamics of the Transformation Processes for Nitrogen and Phosphorus Compounds in the Ecosystem of the Vistula Lagoon of the Baltic Sea using the Methods of Mathematical Modeling

By using mathematical modeling methods, a systematic study of the interaction of hydrobiological, hydrochemical, hydrological and hydrophysical processes that occur in the ecosystem of the Vistula Lagoon (VL) of the Baltic Sea was carried out, taking into account the processes in the active layer of bottom sediments (BS). The features of the dynamics of nitrogen and phosphorus compounds, the turnover time and the components of the balance of compounds of biogenic elements in the VL ecosystem, as well as the degree of their temporal variability have been analyzed. It is shown that the variability of nitrogen and phosphorus compounds in the aquatic environment increases in spring and autumn periods. This is due to an increase in river flow into the lagoon and an increase in the level of external biogenic load on the water area of the VL. Model calculations of matter fluxes allow us to state that the inputs of dissolved organic and suspended matter into the lagoon from external sources and the removal to the Baltic Sea are important processes that significantly affect their content in the VL ecosystem. It has been established that under strong winds the process of sedimentation of suspensions can be largely blocked, and the intensity of BS resuspension can increase significantly. An analysis of the main qualitative and quantitative features of the nature of the temporal dynamics of the DON and DOP turnover times, as well as the mineral compounds of nitrogen and phosphorus, indicates a close conjugation of the processes of transformation of dissolved organic and inorganic substances in the water of the VL. A quantitative assessment of the processes of consumption and excretion of compounds of biogenic elements by different groups of aquatic organisms has been performed, and the important role of heterotrophic bacterioplankton and protozoa in the processes of transformation of compounds of nutrients in the VL ecosystem has been shown. The model can be used to perform scenario modeling and analysis of possible changes in the VL ecosystem under changing climatic and anthropogenic conditions.

The Functional Response of Estuarine Fish Communities to Hydrologic Change in a Semi-Arid Ecosystem

Functional assessment approaches were used to identify the responses of fish to environmental change in the San Antonio Bay System (Texas, USA). Using a 26-year coastal fisheries dataset (1993–2018), multivariate analyses revealed relationships between functional group abundance and freshwater inflows in the upper segments (Hynes Bay and Guadalupe Bay), but the patterns were decoupled from inflows in the lower bay segments (San Antonio Bay, Ayres Bay and Espiritu Santo Bay). In Hynes and Guadalupe Bays, freshwater migrant carnivores accounted for a significant fraction of the community irrespective of the gear, year or flow. Freshwater stragglers (omnivores and carnivores) were often present in the upper reaches of the bay. In the lower reaches, marine migrant omnivores were present during high and low flows in Espiritu Santos Bay, but only during low flows in Ayres Bay. Marine migrant carnivores were more important in gill nets irrespective of the flow conditions. The five most abundant fish were estuarine resident carnivores and omnivores, accounting for 53.5% of the community. Declines in the abundance of functional groups occurred during the 2011–2014 drought, with rebounds in 2015–2018. Functional methodologies provide insights into estuarine ecosystems and can serve as management tools to assess changes in fish assemblages.

Monitoring bay-scale ecosystem changes in bivalve aquaculture embayments using flow cytometry.

Bay-scale empirical evaluations of how bivalve aquaculture alters plankton composition, and subsequently ecological functioning and higher trophic levels, are lacking. Temporal, inter- and within-bay variation in hydrodynamic, environmental, and aquaculture pressure complicate plankton monitoring design to detect bay-scale changes and inform aquaculture ecosystem interactions. Here, we used flow cytometry to investigate spatio-temporal variations in bacteria and phytoplankton (< 20 μm) composition in four bivalve aquaculture embayments. We observed higher abundances of bacteria and phytoplankton in shallow embayments that experienced greater freshwater and nutrient inputs. Depleted nutrient conditions may have led to the dominance of picophytoplankton cells, which showed strong within-bay variation as a function of riverine vs marine influence and nutrient availability. Although environmental forcings appeared to be a strong driver of spatio-temporal trends, results showed that bivalve aquaculture may reduce near-lease phytoplankton abundance and favor bacterial growth. We discuss confounding environmental factors that must be accounted for when interpreting aquaculture effects such as grazing, benthic-pelagic coupling processes, and microbial biogeochemical cycling. Conclusions provide guidance on sampling considerations using flow cytometry in aquaculture sites based on embayment geomorphology and hydrodynamics.

Ecosystem water limitation shifts driven by soil moisture in the Loess Plateau, China

In the context of climate change, the functionality of ecosystems is primarily influenced by the availability of water and energy supply. However, there is limited research that comprehensively uses energy indicators to explore how climate change affects the water and energy limiting states of ecosystems. Here we evaluated the historical and future water and energy limitations using the Ecosystem Limitation Index (ELI) derived from evapotranspiration (ET), soil moisture (SM), net radiation (Rn), and air temperature (Ta), and conducted an in-depth analysis of the dominant factors. The results indicate that: (1) The degree of water limitation deepened initially and then weakened. Over 68 % of the region became drier initially, while over 83 % became wetter later. (2) In terms of area, soil moisture emerged as a critical factor influencing the variations in water and energy constraints within the Loess Plateau. Further research revealed the range of critical soil moisture (CSM) for the transition of water-energy limitation state is 0.286 mm3mm−3, and it varies with changes in temperature, soil texture, vegetation cover, and season. (3) Future projections suggest a transition towards heightened water limitations across the Loess Plateau. These findings underscore the efficacy of ELI in assessing and predicting dynamic ecosystem changes, offering valuable insights into the impacts of climate change on water and energy cycles within semi-arid ecosystems.

Combining APCS-MLR model to evaluate the distribution and sources of rare earth elements in a large catchment

Rare earth elements (REEs), functioning as indicators for environmental tracking, revealing the impacts of human activities on changes in aquatic ecosystems. However, systematic research on the geochemical characteristics of REEs in large river basins remains relatively scarce. Therefore, this research investigates the geochemical properties of REEs within the Yangtze River basin, analyzing the quantity and spatial distribution of REEs in surface aquatic environments across the upstream, midstream, and downstream segments of the Yangtze River, and quantitatively assessing their sources. Results indicate that the REE concentration in the upstream and downstream areas are significantly higher than in the midstream, with average concentrations of 0.69 μg/L, 0.56 μg/L, and 0.39 μg/L, respectively. REEs in the Yangtze River basin are enriched in light rare earth elements (LREEs), exhibiting a slight negative cerium (Ce) anomaly and a pronounced positive europium (Eu) anomaly. The Ce anomaly correlates with pH levels, and the Eu anomaly is largely attributed to the selective chemical decomposition and solubilization of feldspar minerals. Correlation analysis indicates that REE sources are related to manganese (Mn). Utilizing the Absolute Principal Component Scores-Multiple Linear Regression (APCS-MLR) model, the principal sources of REEs are further determined to be mineral sources (36.80%), industrial sources (45.61%), and mixed sources (17.59%). Further analysis suggests that mining and dissolution of Mn-bearing feldspar minerals, along with the discharge of industrial wastewater, considerably influence REE concentrations in the basin. This study reveals the anthropogenic and natural factors influencing the distribution of REEs in the Yangtze River basin, laying a foundational framework for investigating how human activities affect the dispersion of REEs in aquatic environments.

Variation of carbon and nitrogen stable isotope composition in leaves and roots of Littorella uniflora (L.) Asch. in relation to water pH and nutrient availability

In a phytotron experiment, the effects of pH variation and eutrophication on isoetids plants from soft-water lakes specifically the submerged form of Littorella uniflora (L.) Asch. was investigated by analyzing stable carbon and nitrogen isotopes (δ13C and δ15N). Conducted in late October 2020, 200 specimens from Lake Zawiad, near Gdansk, Poland, were examined over 75 days. The study tested three pH levels (∼4.5, ∼7.0, and ∼8.5) and a detailed 12-step nutrient gradient (nitrogen: 0–10 mg/l; phosphorus: 0–0.3 mg/l). The analysis focused on isotopic composition in leaves and roots, revealing that acidic conditions favored higher δ13C values (leaves: −22.67 ‰; roots: −23.23 ‰), suggesting a preference for lighter carbon forms in photosynthesis and intensive use of limited sources of CO2. The neutral pH variant showed the lowest δ13C values (leaves: −25.53 ‰; roots: −25.47 ‰), indicating less optimal conditions. δ15N values exhibited minimal fluctuation across pH levels, with slight variations in acidic and alkaline environments compared to neutral conditions. An observed decrease in δ13C across all pH levels with increased nutrients, alongside a rise in δ15N values, indicates a complex interaction between isotopic composition and environmental factors. Our findings suggest that L. uniflora shows a distinct isotopic response to varying pH levels, with higher δ13C values under acidic conditions potentially indicating enhanced CO2 uptake through a specialized carbon assimilation strategy. This highlights the species' adaptive mechanisms to environmental stressors, suggesting that the isotopic composition of aquatic vegetation can serve as a sensitive indicator of changes in lake ecosystems.

Ecosystem transition due to deer overabundance: Insights from long‐term studies and future considerations

AbstractThe overabundance of certain deer species is emerging as a critical issue in many forested regions across the Northern Hemisphere, including those in Japan. In the field of deer impact studies, the prevailing notion has been that overabundant deer populations could cause drastic changes of ecosystem states. This study comprises a review of the historical discussion surrounding ecosystem changes caused by deer overabundance, from theoretical frameworks to in situ observations and experiments. The synthesis highlights the potential for state transitions, shifting ecosystems from forest to nonforest states, and in some scenarios to a so‐called alternative stable states. However, detecting these transitions poses challenges due to the enduring impacts of past deer activity and the nonequilibrium nature of forest dynamics. Furthermore, this study reveals additional multifield complexities arising from the interactive effects of deer overabundance and global changes on future forest dynamics. To address these challenges, new avenues for research are proposed, emphasizing the importance of sustained efforts in conducting valuable long‐term studies.

SAR image integration for multi-temporal analysis of Lake Manchar Wetland dynamics using machine learning

The Manchar Lake wetland complex, Pakistan’s largest freshwater-lake, faces unprecedented ecological challenges amidst climate change and human pressures, necessitating urgent, data-driven conservation strategies. This study employs cutting-edge multi-sensor remote sensing techniques to quantify and analyze the dynamic changes in this critical ecosystem from 2015 to 2023, aiming to provide a comprehensive understanding of wetland dynamics for informed management decisions. Integrating Sentinel-1 Synthetic Aperture Radar (SAR) and Sentinel-2 multispectral imagery, we assessed changes in wetland extent, vegetation health, and land-use patterns using spectral indices and topographic data. Our methodology achieved classification accuracies exceeding 92% across all study years, revealing significant ecosystem fluctuations. Water body extent exhibited a non-linear trend, expanding from 318.5 km² (5%) in 2015 to 397.0 km² (7%) in 2019, before contracting to 369.9 km² (6%) in 2023. This pattern was corroborated by MNDWI values. Concurrently, vegetation covers dramatically increased from 405.5 km² (7%) in 2019 to 1081.6 km² (18%) in 2023. The Enhanced Vegetation Index (EVI) reflected this trend, decreasing from 0.61 in 2015 to 0.41 in 2019, before recovering to 0.53 in 2023. Land use changes were substantial, with agricultural areas increasing from 118.4 km² (2%) in 2015 to 498.0 km² (8%) in 2023. SAR data consistently supported these observations. Topographic analysis, including the Topographic Wetness Index (TWI), provided crucial insights into wetland distribution and resilience. This comprehensive analysis highlights the complex interplay between natural processes and human influences shaping the Manchar-Lake ecosystem, underscoring the urgent need for adaptive management strategies in the face of rapid environmental change.

Climate‐driven shifts in plant–soil feedback of a perennial grass species

Abstract Plant–soil feedback (PSF) plays a key role in determining the composition of plant communities, and understanding the impact of the ongoing climate change on PSF is thus crucial for predicting the consequences of climate change for ecosystems. Here, we conducted a growth‐chamber experiment to examine possible climate‐driven shifts in PSF of a perennial grass, Festuca rubra, originating from two climatically distinct sites, by using all factorial combinations of soil biota origin, plant origin, and cultivation climate. Soil biota generated more negative PSF effects when grown under the climatic conditions of their origin. This observation suggests that soil biota, especially soil pathogens, are well adapted to their local climate, exhibiting greater efficiency in suppressing plant growth within their climatic conditions. All plants, regardless of their origin, exhibited less negative PSF (expressed as relative performance in live vs. sterilized soil) when grown under warmer climate than under colder climate, likely due to positive effects of increased activity of soil decomposers and enhanced nutrient cycling. Plants showed negative PSF when grown with local soil biota under home climate, and the negative PSF disappeared when plants were grown with foreign biota or in away climates. This suggests that any disruption of the established plant‐soil‐climate interactions may lead to the release of plants from negative PSF, potentially destabilizing plant communities. Synthesis. Our results highlight the adaptions of soil biota to their native climate as key drivers of plant–soil feedback interactions and suggest that climate change could significantly alter these interactions, potentially leading to new plant community dynamics. These findings emphasize the need for further investigations to unravel the mechanisms driving these responses and evaluate their consequences for ecosystem resilience in the face of climate change.