Search

Photodegradation via ultraviolet (UV) radiation is an important factor driving plant litter decomposition. Despite increasing attention to the role of UV photodegradation in litter decomposition, the specific impact of UV radiation on the plant litter decomposition stage within biogeochemical cycles remains unclear at regional and global scales. To clarify the variation rules of magnitude of UV effect on plant litter decomposition and their regulatory factors, we conducted a meta-analysis based on 54 published papers. Our results indicated that UV significantly promoted the mass loss of litter by facilitating decay of carbonaceous fractions and release of nitrogen and phosphorus. The promotion effect varied linearly or non-linearly with the time that litter exposed to UV, and with climatic factors. The UV effect on litter decomposition decreased first than increased on precipitation and temperature gradients, reaching its minimum in the area with a precipitation of 400-600 mm, and a temperature of 15-20 °C. This trend might be attributed to a potential equilibrium between the photofacilitation and photo-inhibition effects of UV under this condition. This variation in UV effect on precipitation gradient was in agreement with the fact that UV photodegradation effect was weakest in grassland ecosystems compared to that in forest and desert ecosystems. In addition, initial litter quality significantly influenced the magnitude of UV effect, but had no influence on the correlation between UV effect and climate gradient. Litter with lower initial nitrogen and lignin content shown a greater photodegradation effect, whereas those with higher hemicellulose and cellulose content had a greater photodegradation effect. Our study provides a comprehensive understanding of photodegradation effect on plant litter decomposition, indicates potentially substantial impacts of global enhancements of litter decomposition by UV, and highlights the necessity to quantify the contribution of photochemical minerallization pathway and microbial degradation pathway in litter decomposition., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Cultural ecosystem services (CES) and disservices shape landscape planning policy to a huge extent. We focus on the benefits and disbenefits associated with CES. The study aimed to explore the co-occurrence of the benefits and disbenefits associated with CES as well as the relationship between spatial and landscape characteristics and specific benefits and disbenefits. We conducted a map-based online questionnaire among visitors of two urban green spaces in Kraków, Poland (Wolski Forest and Jordan Park). Respondents were asked to map places visited and assign them benefits and disbenefits using indicator statements. We found three bundles of benefits (connection to nature, social bonding in nature and responsibility) and five to seven bundles of disbenefits (1). The experiences (e.g., strengthening social bonds) were more concentrated whereas the identities (e.g., reflection) were more blurred spatially owing to their individualistic nature (2). The relationship between benefits/disbenefits and landscape features showed a relatively weak correlation, with a more discernible pattern observed in the case of experiences and capabilities (3). Respondents perceived more human-related disbenefits (overcrowding, noise, rubbish), exhibiting a greater geographical concentration, especially in proximity to tourist attractions (4). The ecosystem-related disbenefits (insects, allergies) were less geographically concentrated (5). Furthermore, the study unveiled differences in the perception of disbenefits across seasons. Visitors of warmer months expressed concerns about overcrowding, insects, and allergies, while those exploring the study areas in winter indicated challenges associated with darkness and snow-covered paths (6). These are important implications for management to increase the comfort of visits to green spaces., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Agnieszka Nowak-Olejnik reports financial support was provided by European Union. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Anthropogenic eutrophication is known to impair the diversity and stability of aboveground community, but its effects on the diversity, composition and stability of belowground ecosystems are not yet fully understood. In this study, we conducted a 9-year nitrogen (N) and phosphorus (P) addition experiment in a semi-arid grassland of Northern China to elucidate the impacts of nutrients addition on soil fungal diversity, functional guilds, and co-occurrence networks. The results showed that N addition significantly decreased soil fungal diversity and altered fungal community composition, whereas P addition had no impact on them. The relative abundance of arbuscular mycorrhizal fungi and leaf_saprotroph were reduced by N and P addition, but P addition enhanced the abundance of saprotrophic fungi. Co-occurrence network analysis revealed that N addition destabilized fungal network complexity and stability, while P addition slightly increased the network complexity. Additionally, the network analysis of N × P interaction revealed that P addition mitigated negative effects of N addition on network complexity and stability. Structural equation modeling (SEM) results suggested that nutrients addition directly or indirectly influenced the fungal community structure through the loss of plant richness and the increase of perennial grass biomass. These findings indicate that in comparison to P addition, N addition exhibits a pronounced negative effect on soil fungal communities. Our findings also suggest that changes in plant functional groups under nutrients deposition are pivotal in shaping soil fungal community structure in semi-arid grassland and highlight the need for a better understanding of the belowground ecosystem dynamics., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Uncovering the spatiotemporal features of ecosystem services (ESs) and their intricate interrelations in large lake basins can facilitate the development of scientific management measures for various ESs. Previous studies have focused less on watershed units and their historical dynamics, and the ecosystem service (ES) driving mechanisms remain unclear. Here, we focused on Hunan Province-the main coverage area of the Dongting Lake Basin (China's second largest freshwater lake), investigated the spatiotemporal characteristics of seven typical ESs and their interactions, identified the ecosystem service bundle (ESB) historical spatial patterns and revealed the socio-ecological driving mechanisms of these ES changes. Results showed that: (1) the spatial distribution of most ESs remained stable in the basin. Food production (FP), water yield (WY), soil conservation (SC) and net primary productivity (NPP) improved over time, whereas nitrogen retention (NR), habitat quality (HQ) and outdoor recreation (OR) declined; (2) tradeoffs were observed between food production and most ESs, whereas synergistic relationships between all ESs except food production. The tradeoff relationship between food production and water yield increased significantly over time, while the synergistic relationship between water yield and nitrogen retention decreased significantly; (3) five ecosystem service bundles were identified. And the transformation of soil conservation area into integrated ecological regulation area mainly occurred from 2000 to 2020, resulting in an increase in the function of ecological regulation services; (4) natural conditions such as precipitation, topography and vegetation, as well as socio-economic factors such as Gross Domestic Product (GDP) and population, were key factors affecting ESs. The interactions among most of these drivers can further elucidate the ES changes. Our results emphasize the need for a watershed-based assessment and a historical dynamic perspective in the sustainable management of ESs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Phototrophic protists are a fundamental component of the world's oceans by serving as the primary source of energy, oxygen, and organic nutrients for the entire ecosystem. Due to the high thermal seasonality of their habitat, temperate protists could harbour many well-adapted species that tolerate ocean warming. However, these species may not sustain ecosystem functions equally well. To address these uncertainties, we conducted a 30-day mesocosm experiment to investigate how moderate (12 °C) and substantial (18 °C) warming compared to ambient conditions (6 °C) affect the composition (18S rRNA metabarcoding) and ecosystem functions (biomass, gross oxygen productivity, nutritional quality - C:N and C:P ratio) of a North Sea spring bloom community. Our results revealed warming-driven shifts in dominant protist groups, with haptophytes thriving at 12 °C and diatoms at 18 °C. Species responses primarily depended on the species' thermal traits, with indirect temperature effects on grazing being less relevant and phosphorus acting as a critical modulator. The species Phaeocystis globosa showed highest biomass on low phosphate concentrations and relatively increased in some replicates of both warming treatments. In line with this, the C:P ratio varied more with the presence of P. globosa than with temperature. Examining further ecosystem responses under warming, our study revealed lowered gross oxygen productivity but increased biomass accumulation whereas the C:N ratio remained unaltered. Although North Sea species exhibited resilience to elevated temperatures, a diminished functional similarity and heightened compositional variability indicate potential ecosystem repercussions for higher trophic levels. In conclusion, our research stresses the multifaceted nature of temperature effects on protist communities, emphasising the need for a holistic understanding that encompasses trait-based responses, indirect effects, and functional dynamics in the face of exacerbating temperature changes., Competing Interests: Declaration of competing interest Anika Happe, Marco J. Cabrerizo, Markus Olsson reports financial support was provided by European Commission. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Ecosystems that offer carbon sequestration by leaching bicarbonate to groundwater are valuable natural capital. One region that may offer this service is the west coast of South Africa. Over 20 % is covered by soil mounds ("heuweltjies") up to 40 m diameter, 2 m high, inhabited by the southern harvester termite Microhodotermes viator and enriched in soil organic and inorganic carbon and soluble minerals. We aimed to generate radiogenic and stable isotope data for soils and groundwater in a region where these data are absent, to 1) verify the atmosphere-soil-groundwater link, and 2) resolve the timing and pattern of calcite dissolution and water infiltration in the landscape. Results show that soil and groundwater sulfate have the same marine aerosol source. Episodic calcite dissolution in mound centers, which increased during periods of global cooling, has been set against background input of marine aerosols since before the Last Glacial according to radiocarbon ( 14 C) ages. Our data push back soil organic carbon 14 C ages of inhabited termite mounds to 13-19 ka (kiloannum, thousand years before present), nest carbonate 14 C ages to 33 ka, and mound soil carbonate 14 C ages to 34 ka, making these the oldest active termite features ever dated. These ages are consistent with soil organic carbon and carbonate 14 C ages of regional, non-mound, coastal petrocalcic horizons formed by accumulation of carbonate leached from their overlying aeolian dune fields. Harvesting activities of termites inject younger organic material around nests >1 m deep, leading to continuous renewal of important soil carbon reservoirs at depth. Termite bioturbation increases the system's ability to dissolve carbonate. The central, bioturbated part of the mounds have greater infiltration depths and greater calcite dissolution, whereas surrounding soils experienced more surface runoff. Calcareous termite mounds offer a mechanism to sequester CO 2 through dissolution and leaching of soil carbonate-bicarbonate to groundwater., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Urban streams are exposed to a variety of anthropogenic stressors. Freshwater salinization is a key stressor in these ecosystems that is predicted to be further exacerbated by climate change, which causes simultaneous changes in flow parameters, potentially resulting in non-additive effects on aquatic ecosystems. However, the effects of salinization and flow velocity on urban streams are still poorly understood as multiple-stressor experiments are often conducted at pristine rather than urban sites. Therefore, we conducted a mesocosm experiment at the Boye River, a recently restored stream located in a highly urbanized area in Western Germany, and applied recurrent pulses of salinity along a gradient (NaCl, 9 h daily of +0 to +2.5 mS/cm) in combination with normal and reduced current velocities (20 cm/s vs. 10 cm/s). Using a comprehensive assessment across multiple organism groups (macroinvertebrates, eukaryotic algae, fungi, parasites) and ecosystem functions (primary production, organic-matter decomposition), we show that flow velocity reduction has a pervasive impact, causing community shifts for almost all assessed organism groups (except fungi) and inhibiting organic-matter decomposition. Salinization affected only dynamic components of community assembly by enhancing invertebrate emigration via drift and reducing fungal reproduction. We caution that the comparatively small impact of salt in our study can be due to legacy effects from past salt pollution by coal mining activities >30 years ago. Nevertheless, our results suggest that urban stream management should prioritize the continuity of a minimum discharge to maintain ecosystem integrity. Our study exemplifies a holistic approach for the assessment of multiple-stressor impacts on streams, which is needed to inform the establishment of a salinity threshold above which mitigation actions must be taken., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

The impacts of wildfire on vegetation and soil erosion have been studied for decades aiming to bring back ecosystems after fire perturbance. However, the influence of fires on above and belowground biodiversity remains far less understood. Biodiversity is critical for supporting ecosystem function, and this data scarcity is hampering managers in adopting effective practices for a proper restoration of burned ecosystems. This limitation could be overcome by future research that should focus post-fire diversity of plants and soil biota, by (i) analysing the environmental factors driving post-fire evolutionary trends; (ii) exploring their interrelations across different spatial and temporal scales; (iii) identifying the variability across fires of different severities and frequency; (iv) ascertaining the post-fire response of individual plant species and soil taxa to fire with or without application of post-fire restoration actions., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Drought and heat caused major disturbance in nature by interfering with plant phenology, and can also alter the vulnerability and resilience of terrestrial ecosystems. Existing research on the Mongolian Plateau has primarily focused on studying the response of the start (SOS) and end (EOS) of the growing season to drought and heat variations. However, there is still a lack of comprehensive understanding regarding the coupled effects of drought and heat on phenology across different land cover types. In this study, we retrieved SOS and EOS based on 34-year (1982-2015) normalized difference vegetation index (NDVI) dataset from Global Inventory Modeling and Mapping Studies (GIMMS). Results showed that grasslands and the Gobi-Desert show rapid advancement in SOS, and forests presented the slowest advancement in SOS, but SOS in croplands were delayed. EOS across four land cover types advanced, with the Gobi-Desert showed the highest rate of advancement and forests the lowest. Using the Palmer Drought Severity Index (PDSI) and soil temperature as the indicators of drought and thermal conditions, the responses of SOS and EOS to these two climate variables were evaluated. The advanced SOS driven by lower drought severity was detected in forests, grasslands, croplands and the Gobi-Desert. The dominant response of EOS to drought severity was positive in croplands, grasslands and forests, except for the Gobi-Desert, where drought severity had negative effects on EOS. Compared with the daily average soil temperature (ST mean ), the daily maximum soil temperature (ST max , daytime), and the daily minimum soil temperature (ST min , nighttime), the daily diurnal soil temperature range (DSTR, where DSTR = ST max  - ST min ) between night and day were the most suitable indicators for assessing the response of SOS and EOS to soil temperature. Strong negative correlation between SOS and the preseason DSTR was pronounced in all land cover types on the Mongolian Plateau. However, EOS was negatively correlated with the preseason DSTR only in the Gobi-Desert. Last but not least, normalized sensitivity assessments reveal that the negative impacts of DSTR on SOS and EOS were the main controlling factors on the Mongolian Plateau phenology, followed by the couple negative effects of drought severity and DSTR., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Fluoroquinolone (FQ) antibiotics have become a subject of growing concern due to their increasing presence in the environment, particularly in the soil and groundwater. This review provides a comprehensive examination of the attributes, prevalence, ecotoxicity, and remediation approaches associated with FQs in environmental matrices. The paper discusses the physicochemical properties that influence the fate and transport of FQs in soil and groundwater, exploring the factors contributing to their prevalence in these environments. Furthermore, the ecotoxicological implications of FQ contamination in soil and aquatic ecosystems are reviewed, shedding light on the potential risks to environmental and human health. The latter part of the review is dedicated to an extensive analysis of remediation approaches, encompassing both in-situ and ex-situ methods employed to mitigate FQ contamination. The critical evaluation of these remediation strategies provides insights into their efficacy, limitations, and environmental implications. In this investigation, a correlation between FQ antibiotics and climate change is established, underlining its significance in addressing the Sustainable Development Goals (SDGs). The study further identifies and delineates multiple research gaps, proposing them as key areas for future investigational directions. Overall, this review aims to consolidate current knowledge on FQs in soil and groundwater, offering a valuable resource for researchers, policymakers, and practitioners engaged in environmental management and public health., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)