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The recalcitrant nature of wheat (Triticum aestivum L.) straw, one of the most abundant agricultural residues, presents challenges for efficient decomposition, limiting nutrient release and organic matter retention in soils. Understanding the effects of tillage practices on wheat straw decomposition and shaping associated microbial communities is essential for enhancing microbial-mediated breakdown and optimizing residue management to enhance soil health, nutrient cycling, and sustainability in agricultural systems. In this study, the effect of different tillage practices on wheat straw decomposition and associated bacterial and fungal community compositions during non-growing and growing seasons were studied. To simulate tillage, litter bags filled with wheat straw were placed at respective soil depths for conventional (22–24 cm) and reduced (8–10 cm) tillage, and on the surface for the no-tillage treatment. The subsets of the litter bags were randomly retrieved after 145 days and at the end of the experiment after 290 days. Statistical analysis revealed that tillage treatments significantly influenced the decomposition rate and nutrient release over time. Overall, the alpha diversity of the decomposition-associated microbial community was not substantially affected by different tillage treatments, while beta diversity exhibited distinct microbial community compositions in relation to tillage practices. The results of this study contribute to a deeper understanding of wheat straw decomposition-associated bacterial and fungal communities' response to different tillage treatments, with observations made at two distinct sampling times (non-growing and growing seasons) under certain edaphic and climatic conditions. [ABSTRACT FROM AUTHOR]

Little is known about how seedlings sense new soil environments and how the rhizosphere bacteriome changes accordingly. It is important to elucidate these changes to better understand feedbacks that contribute to nutrient cycling and plant fitness. Here, we explored how the tomato rhizosphere bacteriome developed weekly throughout the vegetative developmental stage and with variable nitrogen (N) fertilizer additions. Bacterial communities expressing diverse functions highly fluctuated in the first and second week after planting, and these fluctuations diminished progressively after the third week. Bacteria capable of biocontrol stabilized after the fourth week, while those involved in nutrient cycling continued to change in abundance week-to-week. Thus, bacterial specialization may be concomitant with bacteriome stabilization. With N fertilizer application, bacteria with diverse functions continued to fluctuate through the fifth week. However, regardless of fertilization, bacterial communities stabilized by the sixth week. It may take two weeks for roots to select for soil bacteria to assemble a specific rhizosphere bacteriome, but when N is applied, this period extends. Subsequently, roots may select for bacteria that are already established in the rhizosphere rather than from the bulk soil. This study showcases the dynamics of rhizosphere assemblage and how this process is affected by N additions. [ABSTRACT FROM AUTHOR]

High concentrations of ammonium, phosphate, and phenol are recognized as water pollutants that contribute to the degradation of soil acidity. In contrast, small quantities of these nutrients are essential for soil nutrient cycling and plant growth. Here, we reported composite materials comprising biochar, chitosan, ZrO, and Fe3O4, which were employed to mitigate ammonium, phosphate, and phenol contamination in water and to lessen soil acidity. Batch adsorption experiments were conducted to assess the efficacy of the adsorbents. Initially, comparative studies on the simultaneous removal of NH4, PO4, and phenol using CB (biochar), CBC (biochar + chitosan), CBCZrO (biochar + chitosan + ZrO), and CBCZrOFe3O4 (biochar + chitosan + ZrO + Fe3O4) were conducted. The results discovered that CBCZrOFe3O4 exhibited the highest removal percentage among the adsorbents (P < 0.05). Adsorption data for CBCZrOFe3O4 were well fitted to the second-order kinetic and Freundlich isotherm models, with maximum adsorption capacities of 112.65 mg/g for NH4, 94.68 mg/g for PO4 and 112.63 mg/g for phenol. Subsequently, the effect of CBCZrOFe3O4-loaded NH4, PO4, and phenol (CBCZrOFe3O4-APP) on soil acidity was studied over a 60-day incubation period. The findings showed no significant changes (P < 0.05) in soil exchangeable acidity, H+, Mg, K, and Na. However, there was a substantial increase in the soil pH, EC, available P, CEC, N-NH4, and N-NO3. A significant reduction was also observed in the available soil exchangeable Al and Fe (P < 0.05). This technique demonstrated multi-functionality in remediating water pollutants and enhancing soil acidity. [ABSTRACT FROM AUTHOR]

Viruses that infect cyanobacteria are an integral part of aquatic food webs, influencing nutrient cycling and ecosystem health. However, the significance of virus host range, replication efficiency, and host compatibility on cyanobacterial dynamics, growth, and toxicity remains poorly understood. In this study, we examined the effects of cyanophage additions on the dynamics and activity of optimal, sub-optimal, and non-permissive cyanobacterial hosts in cultures of Microcystis aeruginosa and Raphidiopsis raciborskii. Our findings reveal that cross-infectivity can substantially reduce the proliferative success of the cyanophage under conditions of high-density of sub-optimal hosts which suggests phage dispersal limitation as a result of shared infections, in turn impairing their top-down control over the host community. Furthermore, we found that cyanophage addition triggers host strain-specific responses in photosynthetic performance, population size and toxin production, even among non-permissive hosts. These non-lytic effects suggest indirect impacts on co-existing cyanobacteria, increasing the overall complexity and variance in many ecologically relevant cyanobacterial traits. The high variability in responses observed with a limited subset of cyanophage-cyanobacteria combinations not only highlights the intricate role of viral infections in microbial ecosystems but also underscores the significant challenges in predicting the composition, toxicity, and dynamics of cyanobacterial blooms. [ABSTRACT FROM AUTHOR]

Invasion of zebra mussels (Dreissena polymorpha) can have profound effects on lake ecosystems. We investigated the overall ecological effects after invasion and fast expansion of zebra mussels in eight lakes in Denmark belonging to the same watercourse systems but with different morphological and eutrophication characteristics. A few years after the invasion, most of the lakes had experienced profound changes in lake water quality, e.g. chlorophyll a had been reduced by 18–62% and Secchi depth had increased by 38–171%. Nutrient concentrations also decreased, total phosphorus to 37–64% and total nitrogen to 49–77% of pre-invasion concentrations. Seasonally, differences between both summer and winter phosphorus and nitrogen concentrations diminished, suggesting a change in internal nutrient cycling after the invasion. In most lakes, the abundance of submerged macrophytes rose substantially, and often coverage increased by a factor 10 or more, and the maximum colonisation depth increased by up to 5.4 m. Plant species numbers increased markedly in four of the six lakes with macrophyte data. The fish community changed towards higher dominance of potential piscivorous perch and an increase in their body size. The profound effects of zebra mussel invasion may affect lake management and how ecological quality should be interpreted. [ABSTRACT FROM AUTHOR]

The black soldier fly (Hermetia illucens) is a saprophagous insect known for bioconverting organic waste, potentially offering environmental benefits, such as contributing to waste reduction and nutrient cycling. The performance of larvae varies significantly with factors substrate moisture, larval density, and scale of production. Three experiments were conducted using a mix of spent mushroom substrate (SMS) and chicken feed (CF). In the first experiment, 250 larvae were reared on 100 g dry matter (DM) feed at moisture levels of 65–75%. Results showed that the average individual larval weight, total biomass, and feed conversion ratio (FCR) improved with increased moisture. In the second experiment, 300 and 350 larvae/box were tested at 70% and 75% moisture. The highest average individual larval fresh weight (158.6 mg) was observed at 70% moisture with 250 larvae, while the highest biomass was achieved at 75% moisture with 300 larvae. Finally, different scales (10–2,500 g feed with 25–6,500 larvae) were tested with a similar feeding rate. The highest individual larval weight was recorded at the 100 g scale, with no clear correlation between weight and scale. However, the 50 g scale achieved the highest substrate reduction (33.2%). Overall, this study underscores the need to adjust moisture, density, and scale to nutrient conversion efficiency when using SMS, CF or other diets. The optimal results for the SMS feed mix were observed at 75% substrate moisture, 250 larvae per 100 g DM, and at approximately 2 larvae per cm2. [ABSTRACT FROM AUTHOR]

Mixed-species plantations involving Eucalyptus and Acacia trees are an effective alternative for managing sustainable plantations. In this study, we evaluated the growth, productivity, nutrient return, and soil properties of a mixed Eucalyptus hybrid (Eucalyptus camaldulensis Dehnh. × E. urophylla S.T. Blake; E) and Acacia auriculiformis A. Cunn. ex Benth. plantation (A) and Eucalyptus hybrid and A. auriculiformis plantations. The mixed Eucalyptus hybrid and A. auriculiformis plantation included three ratios at E33:A67, E50:A50, and E67:A33, while the Eucalyptus (E100) and A. auriculiformis (A100) plantations were established on degraded lands in the Had Wanakorn Forestry Research and Student Training Station, Prachuap Khiri Khan province, Thailand. Three replications within a plot size of 20 × 20 m2 were designed to plant Eucalyptus hybrid and A. auriculiformis seedlings at a spacing of 2 × 3 m2. The diameters at breast height (DBH) and height (H) of the Eucalyptus hybrid and A. auriculiformis were measured and monitored after planting for five years. The aboveground biomass of the five-year-old mixed and monoculture plantations was then estimated. Litterfall production and nutrient return from the mixed and monoculture plantations were measured for three years. In addition, soil samples at depths of 0–5, 5–10, and 10–20 cm were collected to analyze the soil's chemical properties. Differences in growth, aboveground biomass, litterfall production, nutrient return, and soil properties were analyzed and tested using Tukey's HSD. The results indicated that both the DBH and H of the Eucalyptus hybrid in the mixed and monoculture plantations were not significantly different (p > 0.05). Similarly, the DBH and H of A. auriculiformis in each treatment were also not significantly different (p > 0.05). However, the DBH and H of the Eucalyptus hybrid were higher than those of A. auriculiformis. The aboveground biomass for the mixed plantation ratios E50:A50, E100, E67:A33, and E33:A67 was not significantly different, while the stem biomass was the highest in E100. Litterfall production was influenced by the proportion of the Eucalyptus hybrid relative to A. auriculiformis, but the monoculture A100 plantation had the highest litter production. The nitrogen return estimated for the mixed plantation was between A100 and E100. Similarly, the total nitrogen in the topsoil (0–5 cm) of the mixed plantation was higher than that in the monoculture E100 plantation. These results indicate that mixing A. auriculiformis with Eucalyptus can improve soil nutrients and nutrient cycling and increase nutrient returns, suggesting that mixed plantations are an effective option for sustainable plantation management and can mitigate the negative environmental impacts of Eucalyptus monocultures. [ABSTRACT FROM AUTHOR]

Optimizing forest management requires a comprehensive understanding of how soil properties and microbial communities evolve across different plantation ages. This study examines variations in soil nutrient dynamics, enzyme activities, and bacterial communities in Schima superba Gardn. & Champ plantations of 10, 15, 27, 55, and 64 years. By analyzing soil from depths of 0–20 cm, 20–40 cm, and 40–60 cm, we identified significant age-related trends in soil characteristics. Notably, nutrient contents, including total organic carbon (TOC), total phosphorus (TP), total carbon (TC), total nitrogen (TN), and nitrate nitrogen ( NO 3 − -N), as well as soil water content (SWC), peaked in 55-year-old mature plantations and decreased in 64-year-old over-mature plantations. Enzyme activities, such as urease, sucrase, and acid phosphatase, decreased with soil depth and exhibited notable differences across stand ages. Microbial community analysis indicated the predominance of Acidobacteria, Chloroflexi, Proteobacteria, Actinobacteria, and Verrucomicrobiota in nutrient cycling, with their relative abundances varying significantly with age and depth. Mature and over-mature plantations exhibited higher absolute abundances of functional genes related to methane metabolism, nitrogen, phosphorus, and sulfur cycling. Reduced calcium ion levels were also linked to lower gene abundance in carbon degradation, carbon fixation, nitrogen, and phosphorus cycling, while increased TOC, NH 4 + -N, NO 3 − -N, and AP correlated with higher gene abundance in methane metabolism and phosphorus cycling. Our findings suggest that long-term cultivation of Schima superba enhances soil nutrient cycling. Calcium ion was identified as a significant factor in assessing soil properties and microbial dynamics across different stand ages, suggesting that extended plantation rotations can improve soil health and nutrient cycling. [ABSTRACT FROM AUTHOR]

Implementing thinning practices can enhance the growth of plantation forests and improve soil health. Nevertheless, the impacts of thinning applications on soil quality, large-diameter timber production of Castanopsis hystrix, and ecosystem multifunctionality are poorly understood. Therefore, we chose two sample plots, unthinned (control) and thinned, to investigate productivity and ecosystem multifunctionality after thinning for six years. Results revealed that thinning significantly reduced the soil's bulk density, enhanced large-diameter timber growth, and undermined ecosystem multifunctionality in the short term compared to control (unthinning) treatment. Compared to the control, the thinning treatment considerably enhanced the soil organic carbon (0–30 cm soil layer) and tree diameter at breast height (20–30 cm), and enhanced shrub leaf nitrogen (N), shrub root N, herb aboveground N, Gram-positive bacteria (0–10 cm soil layer), and Gram-positive bacteria (20–30 cm soil layer) contents by 29.61%, 65.29%, 44.61%, 274.35%, and 323.44%, respectively. Furthermore, the thinning application could improve the N and P resorption efficiency more than control. Furthermore, compared with control, thinning treatment maximized decomposition and nutrient cycling function by 11.81% and 143.40%, respectively. Moreover, total PLFA content significantly impacts carbon stocks, wood production, and water regulation functions. In conclusion, this study underscores the considerable potential of thinning in augmenting large-diameter timber production by stimulating the positive effects of forest stands. These findings provide valuable insights for ecosystem multifunctionality elevation and the judicious application of thinning to improve forestry productivity, facilitating sustainable development in the forestry sector. [ABSTRACT FROM AUTHOR]

The document "Updates on Plants, Soil, Microorganisms, and Their Interactions in Forest Ecosystems" highlights the intricate relationships among plants, soil, and microorganisms in forest ecosystems. It emphasizes the importance of these interdependencies for driving ecological processes and ecosystem functions. The research presented in the document explores topics such as forest succession, climate warming, atmospheric nitrogen deposition, and the impact of human-driven environmental changes on nutrient cycling in forest ecosystems. Additionally, the document discusses the role of elevation in influencing plant functional traits, soil characteristics, and soil microbes within forest ecosystems. The findings suggest implications for forest conservation, restoration, and management, emphasizing the need for further research in this area. [Extracted from the article]

The mechanisms by which the soil physical structure, nutrient conditions, understory vegetation diversity and forest meteorological factors influence fine root (<2 mm diameter) characteristics mediated by soil moisture content (SMC) and soil heat flux (SHF) remain uncertain under climate change. Therefore, in this research, continuous observations were made of the fine root growth, death and turnover of cypress plantations, as well as the SMC and SHF under the management of four thinning intensities in hilly areas in central Sichuan from 2021 to 2023. The fine root data were obtained using the microroot canals (minirhizotron) in the study, and the soil hydrothermal data were obtained using the ECH2O soil parameter sensor and the PC-2R SHF data logger. In the time series, the fine root growth, death and turnover of the cypress plantations with different thinning intensities first increased and then decreased throughout the year; the vertical center of the gravity of the fine roots of cypress was concentrated in the 30–50 cm range. This research also revealed that the variability in the SMC decreased with increasing soil depth. Additionally, the SHF was transmitted from greater soil depths to the surface in unthinned cypress plantation at a rate of 0.036 per year, which decreased the heat in the fine root region. However, SHF was transmitted from the soil surface to greater depths at rates of 0.012 per year, 0.08 per year and 0.002 per year, which increased the heat in the fine root area. The redundancy analysis (RDA) and structural equation model (SEM) results indicated that the SMC and soil heat energy distribution pattern obviously affected fine root growth, death and turnover in the cypress plantation. However, the climate conditions in the forest, the characteristics of vegetation in the understory and the physical and chemical characteristics of the soil directly or indirectly affect the characteristics of the fine roots of cypress plantations with changes in thinning intensity. This research provides a basis for understanding ecosystem structure, nutrient cycling and carbon balance and may guide artificial plantation development and management. [ABSTRACT FROM AUTHOR]

Global climate change, characterized by nitrogen (N) deposition and precipitation reduction, can disrupt soil microbial stoichiometry and soil nutrient availability, subsequently affecting soil nutrient cycles. However, the effects of N deposition and precipitation reduction on microbial stoichiometry and the soil nutrient status in temperate forests remain poorly understood. This study addresses this gap through a 10-year field trial conducted in a Korean pine mixed forest in northeastern China where three treatments were applied: precipitation reduction (PREC), nitrogen addition (N50), and a combination of nitrogen addition with precipitation reduction (PREC-N50). The results showed that N50 and PREC significantly increased carbon-to-phosphorus (C/P) and nitrogen-to-phosphorus (N/P) imbalances, thereby exacerbating microbial P limitation, while PREC-N50 did not alter the nutrient imbalances. PREC decreased soil water availability, impairing microbial nutrient acquisition. Both N50 and PREC influenced soil enzyme stoichiometry, leading to increasing the ACP production. The results of redundancy analysis indicated that microbial nutrient status, enzymatic activity, and composition contributed to the variations in nutrient imbalances, suggesting the adaption of microorganisms to P limitation. These results highlight that N addition and precipitation reduction enhanced microbial P limitation, boosting the shifts of microbial elemental composition, enzyme production, and community composition, and subsequently impacting on forest nutrient cycles. [ABSTRACT FROM AUTHOR]

Numerous studies have exhibited that nitrogen (N) addition significantly influenced terrestrial plant N and phosphorus (P) concentration. However, to date, the impacts of N addition on global plant macronutrients (K, Ca, Mg, S) and micronutrients (Na, Al, Fe, Cu, Mn, Zn,), especially microelement, have not been clearly understood. Here, we conducted a meta-analysis to explore the responses of ten variables associated with terrestrial plant nutrients to N addition. Results indicated that N enrichment produced a significant increase in plant Mg, Mn, Cu and Zn concentrations by 3.44, 33.39, 5.01 and 10.24%, respectively, and a notable decrease in plant Ca and Fe concentrations by 2.67 and 4.95%. Among different ecosystems, plant K, Ca, Mg, S, Mn, Cu and Zn exhibited significant increases in grassland, plant K and Ca showed greater decreases in subtropical and boreal forests, and plant Mn and Al notably increased in subtropical forests after N addition. Similarly, N addition significantly enhanced K, Mg, S, Mn, Cu and Zn by 8.61, 12.98, 22.09, 46.02, 6.40 and 11.83% in herbaceous, but not in woody plants. Besides, our results exhibited that environmental factors (ambient N deposition, mean annual temperate, mean annual precipitation, elevation and soil pH values) and experimental factors (N addition rate and form) affected plant nutrients responses to N enrichment. In summary, our study exhibited that N enrichment altered terrestrial plant nutrient contents, with the magnitude and direction of the responses differing among ecosystem type, plant functional group and N addition rate, which have great significance for understanding plant growth, survival strategies and nutrient cycling under increasing ambient N deposition. [ABSTRACT FROM AUTHOR]

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Forest ecosystem nutrient cycling functions are the basis for the survival and development of organisms, and play an important role in maintaining the forest structural and functional stability. However, the response of forest nutrient cycling functions at the ecosystem level to whole-tree harvesting remains unclear. Herein, we calculated the ecosystem nitrogen (N), phosphorus (P), and potassium (K) absorption, utilization, retention, cycle, surplus, accumulation, productivity, turnover and return parameters and constructed N, P, and K cycling function indexes to identify the changes in ecosystem N, P, and K cycling functions in a secondary forest in the Qinling Mountains after 5 years of five different thinning intensities (0% (CK), 15%, 30%, 45%, and 60%). We showed that the ecosystem's N, P, and K cycling parameters varied significantly and responded differently to thinning treatments. As the thinning intensity increased, the N, P, and K cycling function indexes increased by 5%~232%, 32%~195%, and 104%~233% compared with CK. Whole-tree harvesting promoted ecosystem N and P cycling functions through two pathways: (a) directly regulated litter biomass, indirectly affected soil nutrient characteristics, and then regulated ecosystem N and P cycling functions; (b) directly regulated plant productivity, indirectly affected plant and soil nutrient characteristics, and then regulated ecosystem N and P cycling functions. In contrast, whole-tree harvesting mainly indirectly affected the plant and soil nutrient characteristics by directly adjusting the plant productivity, and promoting the ecosystem K cycling function. Furthermore, N and P cycling functions were mainly regulated by understory plant productivity while tree and herb nutrient characteristics were key driving factors for K cycling functions. These findings indicated that whole-tree harvesting significantly improved the ecosystem N, P and K cycling functions, and reveals varied regulatory mechanisms, which may aid in formulating effective measures for sustainable forest ecosystem nutrient management. [ABSTRACT FROM AUTHOR]

Flocculation using natural plant-based biopolymers from Moringa oleifera seeds and Acacia mearnsii flocculant as Tanfloc® (TSG) has emerged as an efficient strategy for microalgae biomass harvesting. This study optimized the recovery process of Nannochloropsis oculata by varying flocculant concentration, sedimentation time, and culture pH. Results revealed that 1.2 mg.L−1 of TSG at pH 8.9 achieved optimal conditions, although TSG proved effective across different pH ranges. Alkaline flocculation (ALK) also enhanced microalgae harvesting, yielding a high harvesting efficiency (>96%) within 30 minutes of sedimentation. Both methods achieved a concentration factor exceeding 20. However, the use of ALK resulted in reduced lipid and carbohydrate content compared to the control condition. Carotenoid levels showed no significant difference. TSG influenced lipid extraction but not fatty acid quality or carbohydrate extraction. Importantly, the residual medium from TSG flocculation could sustain subsequent cultivation cycles without nutrient supplementation, presenting a cost-effective solution for microalgae cultivation and harvesting. [ABSTRACT FROM AUTHOR]

Consumers vary in their excretion of nitrogen and phosphorus, altering nutrient cycles and ecosystem function. Traditional mass balance models that focus on dietary and tissue nutrients have poorly explained such variation in excretion. Here, we contrast diet and tissue nutrient models for nutrient excretion with predation risk, an often overlooked factor, using the Trinidadian guppy (Poecilia reticulata) as our model system. We surveyed guppies at 12 sites spread across two streams with parallel gradients in food quality and predation risk. At each site, we assessed guppy diet, tissue nitrogen (N), and phosphorus (P) content, and N and P excretion. Predation risk best explained guppy excretion, especially P: guppies excreted less in sites with a dominant predator, while traditional models for excretion rate based on diet quality and tissue nutrients failed to explain it. Guppy tissue N (but not P) most closely correlated with guppy diet quality, showing evidence for flexible homeostasis. Our work extends previous laboratory studies' results to natural streams and shows that predation risk alters feeding behavior and physiology, driving substantial variation in guppy nutrient, particularly P, excretion rates. We suggest that predation risk is an important factor determining nutrient excretion variation, warranting further attention. Our results also show that tissue nutrients and excretion nutrients are decoupled. [ABSTRACT FROM AUTHOR]

Viruses are the most abundant biological entities on Earth, and they play a critical role in the environment and biosphere where they regulate microbial populations and contribute to nutrient cycling. Environmental viruses have been the most studied in the ocean, but viral investigations have now spread to other environments. Here, viral communities were characterized in four cave pools in Carlsbad Caverns National Park to test the hypotheses that (i) viral abundance is ten-fold higher than prokaryotic cell abundance in cavern pools, (ii) cavern pools contain novel viral sequences, and (iii) viral communities in pools from developed portions of the cave are distinct from those of pools in undeveloped parts of the same cave. The relationship between viral and microbial abundance was determined through direct epifluorescence microscopy counts. Viral metagenomes were constructed to examine viral diversity among pools, identify novel viruses, and characterize auxiliary metabolic genes (AMGs). Bacterial communities were characterized by 16S rRNA gene amplicon sequencing. Epifluorescence microscopy showed that the ratio of viral-like particles (VLPs) to microorganisms was approximately 22:1 across all sites. Viral communities from pools with higher tourist traffic were more similar to each other than to those from less visited pools, although surprisingly, viruses did not follow the same pattern as bacterial communities, which reflected pool geochemistry. Bacterial hosts predicted from viral sequences using iPHoP showed overlap with both rare and abundant genera and families in the 16S rRNA gene dataset. Gene-sharing network analysis revealed high viral diversity compared to a reference viral database as well as to other aquatic environments. AMG presence showed variation in metabolic potential among the four pools. Overall, Carlsbad Cavern harbors novel viruses with substantial diversity among pools within the same system, indicating that caves are likely an important repository for unexplored viromes. [ABSTRACT FROM AUTHOR]

Stable isotopes of carbon (δ13C) and nitrogen (δ15N) are commonly employed to reconstruct past change in marine ecosystems and nutrient cycling. However, multiple biogeochemical and physical drivers govern spatiotemporal variability of these isotopic signals, particularly in dynamic coastal systems, complicating interpretation. Here, we coupled a modern multi-year (2010–2019) δ13C and δ15N isoscape record from intertidal mussels (Mytilus californianus) with high-resolution ocean model output and satellite chlorophyll-a observations in the California Current System (32°–43° N) to identify major drivers of isotopic variability. Our results show that spatial variations in δ13C are largely related to primary production, whereas spatial δ15N variability is driven by water mass mixing. Major isotopic change was also related to ocean climate variability; however, these effects vary regionally. In northern and central California, δ15N values are predominantly a function of nitrate utilization, whereas in southern California, δ15N varies due to shifts in water mass composition. In all regions, δ13C values are driven by productivity, with the largest changes occurring in southern California. Our findings provide novel insight into regional differences in predominant drivers of isotopic variability, and links to modern ocean climate variability. These findings offer crucial information needed for robust interpretations of California Current palaeoceanographic δ13C and δ15N records. [ABSTRACT FROM AUTHOR]

Plant litter decomposition is a significant ecosystem function that regulates nutrient cycling, soil fertility, and biomass production. It is heavily regulated by nutrient intake. The effects of exogenous nutrients on litter decomposition are not yet fully understood. To determine how Eriobotrya japonica litter decomposition responds to adding nutrients, we used the decomposition litter bag method in the laboratory for 180 days. There were five different nutrient treatment levels were used: control (no addition), low nitrogen addition (LN; 100 kg N·ha−1·year−1), high nitrogen addition (HN; 200 kg N·ha−1·year−1), phosphorus addition (P; 50 kg P·ha−1·year−1), and micronutrient addition (M; 50 kg M·ha−1·year−1). According to a repeated-measures analysis of variance, adding N reduced the remaining mass (p < 0.01) by 4.1% compared to the CK group. In contrast, adding M increased the remaining mass (p < 0.01) by 6.8% compared to the CK group. Adding P had no significant effect on the remaining mass. Although the amount of residual carbon (C) was unaffected, adding N increased the level of residual N in the litter. Litter C content, K content, N concentration, and C/N ratio were linearly correlated to the remaining litter (p < 0.01). Although adding nutrients decreased soil enzyme activity later in the decomposition process, no significant correlation was detected between enzyme activity and the remaining mass. N fertilization treatments decreased the soil microbial diversity index. The addition of nitrogen and micronutrients reduced the abundance of Acidobacteria, while HN addition increased the abundance of Actinobacteria. The addition of micronutrients increased the abundance of Proteobacteria. These results imply that N-induced alterations in the element content of the litter regulated the effects of nutrient inputs on litter decomposition. This study can be a reference for the fertilization-induced decomposition of agricultural waste litter. [ABSTRACT FROM AUTHOR]

Background: Inter-cropping is a reasonable planting pattern between different plants. Inter-cropping of Torreya grandis with Polygonatum sibiricum is a relatively mature planting pattern in China, which has been applied to improve soil ecological environment and reduce the occurrence of pests and diseases in China. However, there is currently limited knowledge on the response of soil microbial communities to this practice. Methods: In this study, we employed Illumina MiSeq sequencing coupled with Functional Annotation of Prokaryotic Taxa (FAPROTAX) and Fungi Functional Guild (FUNGuild) analyses to investigate the dynamic changes in soil microbial communities across seven treated groups [the bulk soil of the T. grandis inter-cropping with P. sibiricum (IB), the bulk soil for mono-cropping of P. sibiricum (PB), the bulk soil for mono-cropping of T. grandis (TB), the P. grandis rhizosphere soil of the T. grandis inter-cropping with P. sibiricum (IPR), the rhizosphere soil for mono-cropping of P. sibiricum (PR), the T. grandis rhizosphere soil of the T. grandis inter-cropping with P. sibiricum (ITR), and the rhizosphere soil for mono-cropping of T. grandis (TR)]. Results: The results showed that the rhizosphere soil of Torreya-Polygonatum inter-cropping exhibited higher microbial community richness, diversity and evenness than mono-cropping (ITR > TR, IPR > PR). Inter-cropping increased the abundance of Micrococcaceae, Xanthobacteraceae, Saitozyma , while decreased Bacillus, Burkholderia, Streptomyces, Cladosporium , and Gibberella significantly of the rhizosphere soil of T. grandis. Further, the abundance of pathogens, such as Fusarium and Neocosmospora , was higher in mono-cropping samples compared to inter-cropping. There existed distinct variations in bacterial and fungal communities among all groups except for IB and TB. The FAPROTAX and FUNGuild analyses results indicated that inter-cropping significantly enhanced soil microbial function associated with nutrient cycling and exhibited a consistent increase in the relative abundance of nitrogen-cycling and carbon-cycling bacteria, and decreased the abundance of plant pathogen guild in the inter-cropping sample ITR compared to the mono-cropping TR. Conclusion: Our findings suggest that T. grandis inter-cropping with P. sibiricum not only enhance the diversity of soil microbial communities, but also improve the nitrogen and carbon cycling functions. In addition, the inter-cropping can effectively reduce the relative abundance of some soil-borne pathogens for T. grandis and P. sibiricum , indicating that this intercropping method may alleviate the impact of pathogens on crops, thus providing assistance for plant disease prevention and sustainable management. [ABSTRACT FROM AUTHOR]

Periphyton communities are fundamental components of freshwater ecosystems that influence water quality, nutrient cycling, and productivity. Additionally, periphyton communities serve as valuable food sources in aquaculture. The periphyton communities on two substrates—heather mats and geotextiles—were compared in four temperate fishponds. After 51 days of immersion, the geotextiles exhibited significantly greater fluorescence, indicating a greater abundance of algae and cyanobacteria. Conversely, the abundance (and biomass) of periphyton invertebrates on heather mats was greater than that on geotextiles, and the difference became more pronounced over time. These differences resulted from significantly greater dipteran larval abundances (biomasses) on the heather mats than on the geotextiles. This study suggested that heather mats can significantly enhance food abundance and availability within the water column under Central European conditions. [ABSTRACT FROM AUTHOR]

The intertidal zone, a dynamic interface of marine, atmospheric, and terrestrial ecosystems, exposes microorganisms to rapid shifts in temperature, salinity, and oxidative stress. Strain LCG004, representing a novel Palleronia species, was isolated from the Lu Chao Harbor's intertidal seawater in the Western Pacific Ocean. The genome of the organism reveals its metabolic versatility, enabling the utilization of various organic substrates—ranging from organic acids, amino acids, to sugars, and encompassing complex carbohydrates—as well as adept handling of inorganic nutrients, thereby highlighting its significant role in the cycling of nutrients. The strain is equipped with multiple osmoprotectant transporters, deoxyribodipyrimidine photo-lyase, and a comprehensive antioxidant defense system, featuring with multiple catalases, peroxidases, and superoxide dismutases, enabling it to withstand ever-changing environmental conditions, UV radiation, and oxidative challenges. Notably, LCG004 exhibited enhanced growth and cell aggregation under oligotrophic conditions, promoted by light exposure, underscoring the significant influence of light on its morphological and physiological attributes. This study elucidates strain LCG004's metabolic characteristics and ecological potential, and offers insights into its contributions to biogeochemical cycles and survival strategies in one of nature's most fluctuating environments. [ABSTRACT FROM AUTHOR]

Introduction: Thinning is a common practice to enhance tree growth, but its effect on rhizosphere soil microorganisms in subtropical secondary evergreen broadleaved forests remains unclear. Methods: This study used 16S rDNA amplicon sequencing to explore soil microflora of five shrubs and five tree species. Results: The results showed that thinning altered nutrient distribution and pH in rhizosphere soil, impacting microbial richness, which varied by tree species. The dominant bacterial phyla were Acidobacteria, Proteobacteria, Actinobacteria, and Firmicutes. Although the dominant microbial species remained largely unchanged, thinning increased the relative abundance of Firmicutes. Thinning intensity between 10-15% significantly altered the structure of soil microbial communities, demonstrating species-specific responses. Discussion: These changes in microbial structure may influence tree growth. This study proposed the potential effects of thinning on rhizosphere soil microorganisms and suggests future research to investigate the specific microbial mechanisms affected by thinning. [ABSTRACT FROM AUTHOR]

Dung serves as a critical resource for diverse organisms, including dung-inhabiting fungi, which play a key role in nutrient cycling. In this study, we examined the decomposition rates and half-lives of dung from ruminant and monogastric herbivores in a microcosm experiment, assessing the impact of autoclaving (fungal exclusion) on decomposition dynamics. Over six months, autoclaved dung decomposed more slowly, retaining greater biomass and highlighting the fungi's role in matter cycling. Decomposition followed a Gaussian linear model, with constants k ranging from 0.02 to 0.03 and half-lives of 19–23 days. Nutrient mineralization varied significantly between the start and end of the experiment, underscoring the contribution of the fungi to nutrient release. Our findings emphasize the ecological importance of dung-inhabiting fungi and suggest areas for future research on factors influencing dung decomposition in terrestrial ecosystems. [ABSTRACT FROM AUTHOR]

Introduction: Epiphytic and endophytic fungi are primary decomposers of forest litter due to their complex species composition and metabolic functions. To clarify the community diversity of phyllospheric fungi and to explore nutrient loss and the role of fungal decomposition, we conducted a study on the decomposition of leaf litter during the 1-year decomposition of Larix gmelinii in the cold temperate zone. Methods: Fungal diversity data were characterized via Single Molecule Sequencing (based on the Sequel II Sequencing System) and statistical analyses in R. Results and discussion: Our findings revealed the presence of 11 known fungal phyla and 29 dominant genera in the larch litter of Greater Khingan. Among these, Basidiomycota and Leucosporidium were dominant in the epiphytic environment, while Ascomycota and Exutisphaerella dominated the endophytic environment. In the early periods of decomposition, phyllospheric fungi became the primary colonizers during litter decomposition by adjusting their life strategies to transition to saprophytic or pathogenic metabolic processes. During decomposition, significant differences in alpha diversity were observed between endophytes and epiphytes. Correlation analysis between these fungi and biological factors revealed a strong relationship between cellulose loss in leaves and the return of N, P, and K. This indicated that the combined biological effects of nutrients, aminosugars, and plant fibers strongly explained changes in community structure. Our results also revealed a significant clustering effect between fungi and biological factors, reflecting the important role of phyllospheric functional fungal communities in carbon fluctuations, cellulose decomposition, and the enrichment of P and K in leaf litter. In summary, this study offers insights into ecosystem processes and nutrient cycling within cold temperate forests, with potential applications for understanding global carbon dynamics. [ABSTRACT FROM AUTHOR]

Eukaryotic microorganisms, or "protists," while often inconspicuous, play fundamental roles in the Earth ecosystem, ranging from primary production and nutrient cycling to interactions with human health and society. In the backdrop of accelerating climate dysregulation, alongside anthropogenic disruption of natural ecosystems, understanding changes to protist functional and ecological diversity is of critical importance. In this review, we outline why protists matter to our understanding of the global ecosystem and challenges of predicting protist species resilience and fragility to climate change. Finally, we reflect on how protistology may adapt and evolve in a present and future characterized by rapid ecological change. [ABSTRACT FROM AUTHOR]

Introduction: The Brahmaputra, a major transboundary river of the Himalayas flowing predominantly through Northeast India, particularly Assam, is increasingly endangered by contamination due to rapid urbanization and anthropogenic pressures. These environmental changes pose significant risks at the microbial level, affecting nutrient cycling and productivity, and thereby impacting river ecosystem health. The next-generation sequencing technology using a metagenomics approach has revolutionized our understanding of the microbiome and its critical role in various aquatic environments. Methods: The present study aimed to investigate the structure of the bacterial community and its functional potentials within the sediments of the Brahmaputra River, India, using high-throughput shotgun metagenomics. Additionally, this study sought to explore the presence of antimicrobial resistance genes in the river's sediment. Results and discussion: Shotgun metagenomics revealed a diverse bacterial community comprising 31 phyla, 52 classes, 291 families, 1,016 genera, and 3,630 species. Dominant phyla included Pseudomonadota (62.47–83.48%), Actinobacteria (11.10–24.89%), Bacteroidetes (0.97–3.82%), Firmicutes (0.54–3.94%), Cyanobacteria (0.14–1.70%), and Planctomycetes (0.30–0.78%). Functional profiling highlighted significant involvement in energy metabolism, amino acid and central carbon metabolism, stress response, and degradation pathways, emphasizing the microbial community's role in ecosystem functioning and resilience. Notably, 50 types of antibiotic resistance genes (ARGs) were detected, with resistance profiles spanning multidrug, aminoglycoside, β -lactam, fluoroquinolone, rifampicin, sulfonamide, and tetracycline classes. Network analysis underscored the intricate relationships among ARG subtypes, suggesting potential mechanisms of resistance propagation. Furthermore, plasmid-related genes and 185 virulence factor genes (VFGs) were identified, indicating additional layers of microbial adaptation and potential pathogenicity within the river sediments. This comprehensive microbial and functional profiling of the Brahmaputra's sediment metagenome provides crucial insights into microbial diversity, resistance potential, and ecological functions, offering a foundation for informed management and mitigation strategies to preserve river health and mitigate pollution impacts. [ABSTRACT FROM AUTHOR]

The relative limitation of microbes by soil organic carbon (SOC), nitrogen (N) and phosphorus (P) is linked with soil microbial activities, so how change of plant species diversity (PSD) affects microbial resource limitation would partly determine its impacts on SOC dynamics and nutrient cycling. However, the responses of microbial resource limitation to increasing PSD have poorly explored. Here, 45 plots covering a natural PSD gradient were used to investigate the effects of PSD on microbial resource limitation in a subtropical forest. Extracellular enzymatic stoichiometry along with a laboratory N and P addition experiment were used to determine microbial resource limitation. Contents of microbial biomass C, N and P significantly increased, but C:P and N:P ratios in microbial biomass were unchanged as PSD increased. Soil microbes were generally co-limited by C and P, but not by N across the 45 plots. Increasing PSD did not alter microbial N limitation, alleviated microbial C limitation and aggravated microbial P limitation. The alleviated microbial C limitation or aggravated microbial P limitation was attributed to increased soil C availability but decreased P availability, which resulted in stimulated soil C:P and N:P ratios and in turn greater C:P and N:P imbalance between soil and microbial biomass under higher PSD. Our results highlight the divergent effects of increasing PSD on microbial resource limitation. Considering that microbial C and P limitations are widespread, the patterns observed in the current study should be applicable broadly. [ABSTRACT FROM AUTHOR]

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Soil microbiomes play key roles in plant productivity and nutrient cycling, and we need to understand whether and how they will withstand the effects of global climate change. We exposed in situ soil microbial communities to multiple rounds of heat, drought, or heat and drought treatments, and profiled microbial communities with 16S rRNA and ITS amplicon sequencing during and after these climatic changes. We then tested how domain and symbiotic lifestyle affected responses. Fungal community composition strongly shifted due to drought and its legacy. In contrast, bacterial community composition resisted change during the experiment, but still was affected by the legacy of drought. We identified fungal and bacterial taxa with differential abundance due to heat and drought and found that taxa affected during climate events are not necessarily the taxa affected in recovery periods, showing the complexity and importance of legacy effects. Additionally, we found evidence that symbiotic groups of microbes important to plant performance respond in diverse ways to climate treatments and their legacy, suggesting plants may be impacted by past climatic events like drought and warming, even if they do not experience the event themselves. [ABSTRACT FROM AUTHOR]

The variation within and across species has afterlife effects on carbon and nutrient cycling through the alteration of litter decomposability. However, the focus on leaves may not reflect a whole-plant economic spectrum of strategies. Here, we assessed the patterns and predictors of flower and leaf-litter decomposition at the intra- (i.e., flowers and leaves of the same species) and inter-specific (i.e., flowers and leaves from different species) levels for 29 tropical woody species in northeast Brazil. We evaluated nine functional litter traits, including structural and chemical traits. Flower litter decomposed, on average, three times faster than leaf litter (11.9% and 39.4% mass remaining, respectively) and exhibited higher water-holding capacity (WHC), leaching (LEA), and N, P, and K content. Otherwise, leaf litter showed higher density (DEN) and Ca, Mg, and Na content. The average relative differences in decomposition rate and functional traits between flower and leaf litter did not differ at both intra- and inter-specific levels. The predictors of decomposition were mostly similar, explaining 39% and 37% of flower and leaf litter, respectively. Leaching, P, Ca, Mg, and Na predict both flower and leaf-litter decomposition. However, WHC exclusively predicted flower-litter decomposition, and DEN, N, and K exclusively predicted leaf-litter decomposition. The observed differences in decomposition rate and functional traits between flower and leaf litter indicate that the afterlife effects differ between these plant organs and leverage the role of flower litter and its secondary consequences to nutrient and carbon cycling on ecosystems. [ABSTRACT FROM AUTHOR]

This study explores the diversity and functions of microbiomes in ancient agroecosystems of the Mixteca Alta Geopark (MAG). Microbiome analysis could provide insights into soil bacterial communities and their role in enhancing soil fertility, nutrient cycling, and plant growth. We used 16S rRNA gene amplicon sequencing to identify key features in the composition of the microbiota of the Lama-bordo, Valley, and Terrace agroecosystems in MAG. Analysis of agroecosystem soils revealed 21 bacterial phyla, with Acidobacteria, Proteobacteria, Actinobacteria, and Chloroflexi dominating. These microbial communities contribute to soil health, carbon cycling, and disease suppression. The study identified specific phylogroups and metabolic pathways associated with nutrient-rich environments like Lama-bordo and Valley, and nutrient-poor, sandy soils like Terrace. Soils from Lama-bordo and Valley were grouped due to microbiome similarity despite geographic separation, whereas Terrace soils differed. Nutrient-rich Lama-bordo and Valley soils host copiotrophic bacteria, while nutrient-poor Terrace soils favor oligotrophic species like Acidobacteria. Functional analysis of microbiomes reveals distinct metabolic pathways, including antibiotic biosynthesis (streptomycin, vancomycin) suggesting a role in plant disease resistance, amino acid pathways indicating active nitrogen cycling, and vitamin B5 and lipoic acid pathways contributing to energy metabolism and antioxidant functions. [ABSTRACT FROM AUTHOR]

Litter decomposition is important for soil nutrient cycling, but how the quality of litter links to nutrient dynamics is still unclear. In this work, high-quality Populus alba × P. Berolinensis, widely planted in Northeast China, and low-quality maize straw were selected as samples for a comparative study. In a short-term controlled litter decomposition incubation experiment, we applied different concentrations (25 u/g and 50 u/g) of biocatalyst (cellulase) to accelerate litter decomposition. Destructive sampling was conducted at 3, 7, 14, and 28 days to examine the influence of exogenous cellulase and litter with varying C:N ratios on the stoichiometric balance of soil carbon and nitrogen contents, as well as associated enzymatic activity. Litter addition significantly increased soil nutrients. Low nitrogen limited nutrient release during the decomposition of maize straw. After treatment, the soil organic carbon (SOC), total nitrogen (TN), microbial biomass carbon (MBC), and microbial biomass nitrogen (MBN) in maize straw were 11.7%, 11.35%, 24.49%, and 39.7% lower than those in high-quality Populus alba × P. Berolinensis, respectively. Exogenous cellulase addition increased microbial biomass and β-D-glucosidase activity. The promotion of soil urease (S-UE), sucrase (S-SC), and β-D-glucosidase (S-β-GC) activities was more significant in combination with litter and exogenous cellulase. In addition, soil nutrients were directly affected by the litter C:N ratio and indirectly affected by cellulase. Overall, these results suggest that high-quality litter better facilitates soil nutrient cycling and accumulation due to its higher carbon and nitrogen release. [ABSTRACT FROM AUTHOR]

A major consequence of anthropogenic climate change is the intensification and extension of drought periods. Prolonged drought can alter conditions in drained peatlands and cause disturbances in microbial communities in the topsoil layer of the peat. Varying environmental conditions throughout the growing season, such as the availability of organic matter and nutrients, temperature and water table, further impact these communities and consequently affect carbon and nutrient cycles. The impact of drought and new forestry practices is largely unknown in drained peatland forests. We examined how microbial communities change over a growing season in different harvesting intensities (continuous cover forestry, clear‐cut and uncut) in a drained peatland site using bacterial 16S and fungal ITS2 rRNA analysis. We found seasonal differences in bacterial and fungal diversity and species richness, and subtle changes in microbial communities at the phylum and genus levels when comparing various environmental factors. Diversity, species richness and relative abundance differed in spring compared to summer and autumn. However, significant differences in the microbial community structure were not detected. Understanding the responses of microbial communities to disturbances like drought and other environmental factors provides new insights into the consequences of climate change on drained forested peatlands. [ABSTRACT FROM AUTHOR]

River network connectivity (RC) describes the hydrologic exchange of water, nutrients, sediments, and pollutants between the river channel and other "sites" via heterogenous flowpaths along the river corridor. As water moves downstream it carries these constituents, creating a stream‐to‐ocean continuum of connectivity that regulates global water, carbon, and nutrient cycling. River network connectivity models have developed over many decades, culminating in recent years with network‐scale RC models that explicitly simulate the transport and exchange of water and elements from headwaters to coasts, sometimes requiring models to contain tens of millions of river reaches. These advances provide transformative insights into the aggregate effects of RC on water and material transport across scales from local to global. Yet, recent reviews have pointed to several challenges that need to be overcome to continue advancing network‐scale RC modeling. In service of these goals, I summarize recent network‐scale RC maps and models to identify similarities and differences across the large‐scale RC modeling landscape. Although our computational and upscaling abilities have significantly improved and have revealed new insights, current models are still limited by the quantity, quality, resolution, and lack of standardization of the available in situ databases and source data maps necessary for the modeling. This suggests that we can extend recent advances if we keep improving these source datasets, while continuously revisiting our physics and theory to explain those new data. In doing so, we will continue to expand the role of network‐scale RC models in informing water quality modeling and management into the future. [ABSTRACT FROM AUTHOR]

Fine root decomposition is an important driver of forest carbon (C) and nutrient cycling. Harvesting operations may affect fine root decomposition rates by altering root properties and environmental conditions, but our understanding of root dynamics is limited. In this study, we investigated the chemistry, mass loss, element release (C, nitrogen (N), and phosphorus (P)), and compound release (lignin and cellulose) of decaying fine roots in a 26 year-old Chinese fir plantation seven years after low- and high-intensity thinning (30% and 70% tree removal) using two root size classes (< 1 mm and 1–2 mm diameter). Low-intensity thinning (LIT) did not affect mass loss in either fine root class or the release of fine root elements or compounds during decomposition. Similarly, high-intensity thinning (HIT) had no effect on the decomposition of large fine roots. However, compared with LIT and no thinning, HIT reduced the decay rates and lignin and cellulose losses of small fine roots. This reduction was related to an increase in the root lignocellulose index (lignin/[lignin + cellulose]) and a decrease in soil invertase activity. Interestingly, thinning did not affect root C, N, or P loss during decomposition. In summary, our results suggest that thinning intensity as well as root size and chemistry should be considered when studying fine root dynamics in managed forests. [ABSTRACT FROM AUTHOR]

Inputs of fertilizer nutrients in agriculture are estimated to have contributed to > 40% increase in crop production over the past century, resulting in widespread benefits to food security and prosperity. However, fertilizer nutrient redistribution has fundamentally altered global and local nutrient cycles alike, yielding trade-offs in socioeconomic and environmental outcomes. David Pimentel's body of work on the management of energy, water, and soil resources in agriculture, along with his perspectives on agronomy and sustainable resource management, resonates with a critical understanding of the consequences of nutrient redistribution in agriculture. With Pimentel's legacy in mind, we consider trade-offs of global nutrient redistribution, improved recycling of nutrients in agricultural systems, as well as the challenges of, and opportunities for, transformations that seek to adjust nutrient cycles in modern agriculture. Pimentel's legacy and contributions provide valuable insight into agriculture's wicked nutrient challenge, as he framed the costs and opportunities of production systems across different scales of food production, developed foundational understanding of global resource challenges, promoted often marginalized or underemployed management strategies to enhance agriculture's ecosystem services, confronted conventional wisdom and popular trends, and appropriately, attacked the use of "silver bullets" as singular solutions to ecological challenges and instead promoted systems-level analyses. [ABSTRACT FROM AUTHOR]

Scavenging removes carrion or littered food waste from the environment, promoting nutrient cycling, and reducing waste management costs. These ecosystem services are important in urban environments, where high human population densities result in increased littered food waste. It is unclear how the magnitude of scavenging across urban-rural gradients is influenced by agent, land-cover type, and patch size. We investigated scavenging provision by vertebrates and invertebrates across a gradient of urbanisation, based on impervious surface cover, in woodlands and gardens in Liverpool, UK. The percentage dry weight loss of bait after 48 h, deployed within vertebrate exclusion cages or exposed to vertebrates and invertebrates, was used to quantify scavenging provision. General linear mixed effects models were used to assess the relative contributions of vertebrates and invertebrates across an urban-rural gradient, variation in scavenging between woodlands and gardens, and the effects of semi-natural vegetation cover on scavenging in gardens. We consider patch size as a preliminary assessment of how fragmentation influences scavenging. Vertebrates contributed substantially more to scavenging than invertebrates across the urbanisation gradient. Vertebrate scavenging was greater in woodlands than gardens, while invertebrate scavenging remained consistent. Scavenging increased with patch size in gardens, but not woodlands. Vertebrate scavenging increased with patch size and garden semi-natural vegetation cover. Urban woodlands and gardens make important contributions to scavenging-mediated ecosystem services. There is a need to increase the cover of semi-natural vegetation in gardens to increase their contributions, and protect and expand woodlands, especially in areas with a high demand for scavenging-mediated ecosystem services. [ABSTRACT FROM AUTHOR]

Aquatic fungi, especially aquatic hyphomycetes, are promising bioindicators for assessing the health and integrity of freshwater ecosystems. Their sensitivity to a wide range of environmental stressors, coupled with their essential roles in ecological processes such as organic matter decomposition and nutrient cycling, establish them as important tools for monitoring ecological disturbances. By examining aquatic fungal responses at various biological levels—from molecular mechanisms to ecosystem dynamics—ecologists are able to uncover valuable information about the functioning of freshwater habitats. Despite challenges such as the complexity of fungal communities and knowledge gaps, the prospects for using aquatic fungi as bioindicators are encouraging. Advancing research and technological innovations are expected to refine our understanding of the ecological roles of aquatic fungi and enhance their use in detecting impacts on freshwater ecosystems. The inclusion of these organisms in environmental monitoring programmes alongside other bioindicators could significantly improve our ability to detect and mitigate the effects of both natural and anthropogenic environmental changes, leading to more effective conservation strategies. [ABSTRACT FROM AUTHOR]

Understanding ecosystem service trade-offs and synergies is the foundation for achieving the efficient management of the ecosystem and improving human well-being. Therefore, in this paper, multi-scale trade-offs and synergies among eleven secondary ecosystem service (ES) types of four ecosystem service categories in the mountainous areas of North China in 2015 are assessed using statistical methods and spatial analysis, and their driving factors are analyzed, including natural factors and socioeconomic factors. The results show that for the study area, only the raw material production service and nutrient cycle maintenance service, water supply service and hydrological regulation service, environmental purification service and biodiversity maintenance service, environmental purification service and aesthetic landscape service, and biodiversity maintenance service and aesthetic landscape service show extremely strong synergistic correlations at four spatial scales. The spatial autocorrelation among services at different scales is basically consistent with the statistical correlation, but the degree of correlation varies. Unlike the grid, township, and county scales, all service pairs are spatially autocorrelated across the study area at the land use type scale, and the clustering characteristics are more obvious and similar. All service pairs are synergistic with low–low values at the mountain–plain junction in the Taihang Mountain (THM) and in the northern part of the Bashang region (BSR). The spatial trade-offs and synergies of the regulating and maintenance services in the study area are closely related to the spatial distribution of land use types. The main natural influence on the synergistic trade-offs of ecosystem services (ESs) at the township scale is elevation, while socioeconomics are mainly influenced by population and GDP. This study can contribute to strengthening decision makers' understanding of the spatial scales of ES relationships in mountain areas and the extent to which different natural and socioeconomic factors influence them. [ABSTRACT FROM AUTHOR]

Nonliving resources frequently flow across ecosystem boundaries, which can yield networks of spatially coupled ecosystems. Yet the significance of resource flows for ecosystem function has predominantly been understood by studying two or a few coupled ecosystems, overlooking the broader resource flow network and its spatial structure. Here, we investigate how the spatial structure of larger resource flow networks influences ecosystem function at metaecosystem scales by analyzing metaecosystem models with homogeneously versus heterogeneously distributed resource flow networks but otherwise identical characteristics. We show that metaecosystem function can differ strongly between metaecosystems with contrasting resource flow networks. Differences in function generally arise through the scaling up of nonlinear local processes interacting with spatial variation in local dynamics, the latter of which is influenced by network structure. However, we find that neither network structure guarantees the greatest metaecosystem function. Rather, biotic (organism traits) and abiotic (resource flow rates) properties interact with network structure to determine which yields greater metaecosystem function. Our findings suggest that the spatial structure of resource flow networks coupling ecosystems can be a driver of ecosystem function at landscape scales. Furthermore, our study demonstrates how modifications to the structural, biotic, or abiotic properties of metaecosystem networks can have nontrivial large-scale effects on ecosystem function. [ABSTRACT FROM AUTHOR]

Salt marshes exist at the terrestrial-marine interface, providing important ecosystem services such as nutrient cycling and carbon sequestration. Tidal inputs play a dominant role in salt marsh porewater mixing, and terrestrially derived freshwater inputs are increasingly recognized as important sources of water and solutes to intertidal wetlands. However, there remains a critical gap in understanding the role of freshwater inputs on salt marsh hydrology, and how this may impact marsh subsurface salinity and plant productivity. Here, we address this knowledge gap by examining the hydrologic behavior, porewater salinity, and pickleweed (Sarcocornia pacifica also known as Salicornia pacifica) plant productivity along a salt marsh transect in an estuary along the central coast of California. Through the installation of a suite of hydrometric sensors and routine porewater sampling and vegetation surveys, we sought to understand how seasonal changes in terrestrial freshwater inputs impact salt marsh ecohydrologic processes. We found that salt marsh porewater salinity, shallow subsurface saturation, and pickleweed productivity are closely coupled with elevated upland water level during the winter and spring, and more influenced by tidal inputs during the summer and fall. This seasonal response indicates a switch in salt marsh hydrologic connectivity with the terrestrial upland that impacts ecosystem functioning. Through elucidating the interannual impacts of drought on salt marsh hydrology, we found that the severity of drought and historical precipitation can impact contemporary hydrologic behavior and the duration and timing of the upland-marsh hydrologic connectivity. This implies that the sensitivity of salt marshes to climate change involves a complex interaction between sea level rise and freshwater inputs that vary at seasonal to interannual timescales. [ABSTRACT FROM AUTHOR]

This review evaluates regenerative aquaculture (RA) technologies and practices as viable pathways to foster resilient, ecologically restorative aquaculture systems. The key RA technologies examined include modern periphyton technology (PPT), biofloc technology (BFT), integrated multitrophic aquaculture (IMTA), and alternative feed sources like microalgae and insect-based diets. PPT and BFT leverage microbial pathways to enhance water quality, nutrient cycling, and fish growth while reducing environmental pollutants and reliance on conventional feed. IMTA integrates species from various trophic levels, such as seaweeds and bivalves, to recycle waste and improve ecosystem health, contributing to nutrient balance and reducing environmental impact. Microalgae and insect-based feeds present sustainable alternatives to fishmeal, promoting circular resource use and alleviating pressure on wild fish stocks. Beyond these technologies, RA emphasizes sustainable practices to maintain fish health without antibiotics or hormones. Improved disease monitoring programs, avoidance of unprocessed animal by-products, and the use of generally recognized as safe (GRAS) substances, such as essential oils, are highlighted for their role in disease prevention and immune support. Probiotics are also discussed as beneficial microbial supplements that enhance fish health by promoting gut microbiota balance and inhibiting harmful pathogens. This review, therefore, marks an important and essential step in examining the interconnectedness between technology, agroecology, and sustainable aquaculture. This review was based on an extensive search of scientific databases to retrieve relevant literature. [ABSTRACT FROM AUTHOR]

Tropical trees that remain evergreen and exhibit leaf litterfall that is gradual over time coexist with trees that are seasonally deciduous and exhibit pulsed litterfall. The manner in which these trees acquire, store, and contribute nutrients to the biogeochemical cycle may differ. Green and senesced leaves from deciduous Ficus prolixa trees were compared with those from Ficus tinctoria on the island of Guam. The results enabled stoichiometry and resorption calculations. F. prolixa's young green leaf nitrogen (N) and potassium (K) concentrations were double, and the phosphorus (P) concentration was triple, those of F. tinctoria. Concentrations converged as the leaves aged such that no differences in concentration occurred for senesced leaves, indicating that nutrient resorption proficiency did not differ between the two species. In contrast, the resorption efficiency was greater for F. prolixa than F. tinctoria for all three nutrients. The N:P values of 6–11 and K:P values of 5–7 were greater for young F. tinctoria leaves than young F. prolixa leaves. The N:K values were 1.1–1.6 and did not differ between the two species. No differences in pairwise stoichiometry occurred for senesced leaves for any of the nutrients. These Guam results conformed to global trends indicating that seasonally deciduous plants are more acquisitive and exhibit greater nutrient resorption efficiency. The differences in how these two native trees influence the community food web and nutrient cycling lies mostly in the volume and synchronicity of pulsed F. prolixa litter inputs, and not in differences in litter quality. These novel findings inform strategic foresight about sustaining ecosystem health in Guam's heavily threatened forests. [ABSTRACT FROM AUTHOR]

Long-term continuous cropping exacerbates nutrient loss and deteriorates soil quality. To achieve high yields and economic gains, continuous farming is often practiced, disregarding soil carrying capacity and degradation. This practice has been prevalent in the regions that serve as horticultural centers, supplying vegetables to various areas. This study aimed to elucidate the specific impacts of continuous cropping on soil chemical properties, providing new scientific insights into nutrient depletion in highland horticultural regions. By analyzing soil samples from agricultural lands with a history of prolonged continuous cultivation in Bali Province, this research sought to identify the previously unreported patterns of soil chemical property decline. Laboratory analyses quantified essential soil chemical properties based on established soil quality indices. The results revealed significant reductions in key nutrients, with nitrogen levels ranging from 0.10% to 0.38% and phosphorus levels from 1.84 ppm to 5.31 ppm. Additionally, soil properties such as cation exchange capacity (CEC) (20.68-22.23 me 100g-1), base saturation (38.71-47.62%), and organic carbon (1.56-2.96%) exhibited moderate limitations. These findings underscore the susceptibility of soil chemical properties to continuous cropping systems and their adverse effects on agricultural productivity. A limitation of this study is the focus on soil samples from a single season, without accounting for climatic variability, suggesting a need for future time-series analyses. This research uniquely demonstrated the significant nutrient depletion associated with prolonged continuous cultivation. To mitigate these effects, the authors advocate for crop rotation, incorporation of crop residues into the soil, and the use of organic fertilizers to preserve soil health, sustain long-term agricultural productivity, and maintain environmental balance. [ABSTRACT FROM AUTHOR]

Motivation: Terrestrial predators play key roles in cycling nutrients, as well as limiting prey populations, and shaping the behaviour of their prey. Prehistoric, historic and ongoing declines of the world's predators have reshaped terrestrial ecosystems and are a topic of conservation concern. However, the availability of ecologically relevant predator functional traits is limited, hampering efforts to understand macroecological changes in this ecologically important functional group. Here, we present CarniTraits, a comprehensive open‐access functional trait database of all late Quaternary (~130,000 ybp) terrestrial mammalian predators (149 species, ≥1 kg body mass, ≥50% vertebrate meat consumption). Main Types of Variables Contained: Mammalian terrestrial predator functional traits including body mass, diet, scavenging, locomotion, cooperative hunting, hunting habitat, hunting method, bone consumption, temporal activity patterns, brain mass and encephalisation quotient. Spatial Location and Grain: Global. Time Period and Grain: Late Quaternary (the last ~130,000 years). Major Taxa and Level of Measurement: All late Quaternary terrestrial mammalian predators (149 species, ≥1 kg body mass, ≥50% vertebrate meat consumption). Software Format: csv. [ABSTRACT FROM AUTHOR]

Soil nutrient distribution in desert grasslands is predominantly influenced by climatic factors, particularly precipitation and temperature. Siziwang Banner, situated within the desert grassland belt of Inner Mongolia, represents a typical arid zone where soil nutrient dynamics are shaped by the interplay of precipitation, temperature, and topography. This study aims to investigate the spatial distribution of soil nutrients and assess the dominant role of climatic factors in this region, using geostatistical analyses and GIS techniques. The results reveal that soil nutrients exhibit higher concentrations in surface layers, gradually decreasing with depth. Horizontally, a pronounced gradient can be observed, with nutrient levels being higher in the southern regions and lower in the northern regions. Precipitation and temperature emerge as decisive factors driving these patterns; increased precipitation enhances the accumulation of soil organic matter and nitrogen, whereas elevated temperatures accelerate decomposition of organic matter, leading to nutrient losses. These findings underscore the critical role of climatic factors in governing soil nutrient distribution, offering valuable insights for soil management and ecological restoration efforts in arid ecosystems. [ABSTRACT FROM AUTHOR]

Biological soil crusts are integral to Arctic ecosystems, playing a crucial role in primary production, nitrogen fixation and nutrient cycling, as well as maintaining soil stability. However, the composition and complex relationships between the diverse organisms within these biocrusts are not well studied. This study investigates how the microbial community composition within Arctic biocrusts is influenced by environmental factors along an altitudinal gradient (101 m to 314 m). Metagenomic analyses were used to provide insights into the community composition, revealing that temperature, pH, and nutrient availability significantly shaped the community. In contrast, altitude did not directly influence the microbial composition significantly. Eukaryotic communities were dominated by Chloroplastida and fungi, while Proteobacteria and Actinobacteria prevailed among prokaryotes. Cyanobacteria, particularly orders such as Pseudoanabaenales, Pleurocapsales, and Nostocales, emerged as the most abundant photoautotrophic organisms. Our findings highlight the impact of environmental gradients on microbial diversity and the functional dynamics of biocrusts, emphasizing their critical role in Arctic tundra ecosystems. Arctic biocrusts are intricate micro-ecosystems, whose structure is strongly shaped by local physicochemical parameters, likely affecting essential ecological functions. [ABSTRACT FROM AUTHOR]

The subalpine grassland ecosystem is sensitive to climatic changes. Previous studies investigated the effects of warming on grassland ecosystems at a single altitude, with little information about the response of subalpine meadows to warming along altitude gradients. This study aimed to evaluate the effects of warming on aboveground grass, belowground soil properties, and fungal community along altitude gradients in the subalpine meadow of Mount Wutai using the high-throughput sequencing method. Warming reduced the restriction of low temperatures on the growth of subalpine grass, resulting in increasing grass biomass, community height, and coverage. More grass biomass led to higher soil organic carbon resources, which primarily affected fungal community composition following warming. Warming might induce more stochastic processes of fungal community assembly, increasing fungal diversity at low altitudes. In contrast, warming triggered more deterministic processes to decrease fungal diversity at medium and high altitudes. Warming might improve the efficiency of soil nutrient cycling and organic matter turnover by increasing the relative abundance of soil saprotrophs and improving fungal network connectivity. The relative abundance of certain grass pathogens significantly increased following warming, thereby posing potential risks to the sustainability and stability of subalpine meadow ecosystems. Overall, this study comprehensively evaluated the response of the subalpine meadow ecosystems to warming along altitude gradients, clarifying that warming changes soil fungal community composition at different altitudes. The long-term monitoring of pathogen-related shifts should be conducted in subalpine meadow ecosystem following warming. This study provided significant scientific insights into the impact of future climatic changes on subalpine ecosystems. [ABSTRACT FROM AUTHOR]