Increase In Species Richness Research Articles

Are visitors, biodiversity or timber production better for nature conservation? Findings from an econometric analysis of the management costs of protected areas in Serbia.

Protected areas (PAs) are designed to provide a wide range of ecosystem services (ES) and to conserve biodiversity, alongside cultural values. Understanding the production processes within PAs is crucial to decipher the relationships between different ES, including primary (timber) production and the provision of public goods, and to assess their degree of 'jointness'. This article models PA management as a joint production activity involving multiple outputs, including biodiversity, recreation, and timber production. Using panel data on management costs from 57 PAs in Serbia (representing 82% of the country's protected area), we estimate a variable cost function, that accounts for potential endogeneity due to unobserved PA-specific heterogeneity. Our results show that increasing species richness and extending strict protection zones leads to additional management costs, but with different elasticities. A 10% increase in species richness outside strict zones increases costs by 4.9%, while within strict zones the increase is 5.77%. Timber production shows diseconomies of scale, suggesting that large-scale timber operations should be limited. Marginal cost estimates show that managing one additional species costs €11.80, one additional visitor costs €0.41 and one additional cubic metre of timber costs €44.43. We find no evidence of jointness between timber production and recreation, but there is competition between timber production and biodiversity. Conversely, biodiversity and recreation show complementarity in terms of protection costs. These findings are consistent with the Serbian PA management approach, which uses a land-sparing principle by spatially separating activities. This zoning strategy facilitates coexistence, allowing biodiversity to support local tourism and benefit from recreational activities.

Low oxygen but dynamic marine redox conditions permitted the Cambrian Radiation.

Whether metazoan diversification during the Cambrian Radiation was driven by increased marine oxygenation remains highly debated. Repeated global oceanic oxygenation events have been inferred during this interval, but the degree of shallow marine oxygenation and its relationship to biodiversification and clade appearance remain uncertain. To resolve this, we interrogate an interval from ~527 to 519 Ma, encompassing multiple proposed global oceanic oxygenation events. We integrate the spatial and temporal distribution of shallow water, in situ reef metazoans, and trilobites, with high-resolution multi-proxy redox data through the highly biodiverse Siberian Platform. We document primarily dysoxic water column conditions, suggesting that early Cambrian metazoans, including motile skeletal benthos, had low oxygen demands. We further document oxygenation events coincident with positive carbon isotope excursions that led to modestly elevated oxygen levels. These events correspond to regional increases in species richness and habitat expansion of mainly endemic species, offering a potentially globally applicable model for biodiversification during the Cambrian Radiation.

P1352 Segmental Mucosal Microbiome Variations Across Different Inflammation Extents in Ulcerative Colitis

Abstract Background Ulcerative colitis (UC) is a chronic inflammatory condition characterized by a relapsing-remitting course and represents a major subtype of inflammatory bowel disease (IBD). The gut microbiome plays a pivotal role in the pathogenesis and progression of UC. However, the potential differences in the mucosal microbiome composition across colonic segments, depending on the extent of inflammation in UC, remain poorly explored. Methods we investigated the differences in the mucosal microbiome according to colonic segments in patients with proctitis (R), Lt side colitis (L), pancolitis (P) and remission (RE). A total of 36 UC patients who underwent endoscopic evaluation between March 2023 and July 2024 were finally enrolled. The patients were allocated by disease extent to R (n=18,50.0%), L (n=5, 13.9%), P (n=3, 8.3%) and RE (n=10, 27.8%) groups. The mucosal microbiomes of ascending colon (AC), descending colon (DC), and rectum (RT) were evaluated. Total genomic DNA was extracted from the samples, and the character of the microbiome was determined by sequencing the V3-V4 region of the 16s rRNA gene (Miseq). Results The mucosal microbiome of the RE group exhibited similar alpha diversity across all colonic segments. In contrast, the R and L groups demonstrated increased species richness and evenness in the rectum and descending colon compared to the RE group. However, P group showed consistently low species richness and diversity across all segments compared to the RE group, and with no significant segmental differences within the group. Taxonomic composition analysis at the genus level revealed that segments with active inflammation were enriched with Clostridium innocuum, Campylobacteria, Fusobacteriota, and Alistipes, while Serratia, Rhizorhapis, and Sediminibacterium were depleted compared to the RE group. In beta diversity, the microbiome composition was not different depending on the segment in the RE and P group. In the R and L group, the microbiome composition of the rectum and descending colon were similar but separate from the ascending colon. Conclusion In summary, the mucosal microbiome in inflamed segments differs from that in segments with remission. In cases of pancolitis, the mucosal microbiome exhibited no segmental differences but demonstrated a distinct overall pattern compared to other groups. Evaluating the segmental mucosal microbiome may offer valuable clinical insights into the progression of UC and aid in predicting the extent of inflammation.

Responses of fish to nationwide improvements in the water quality of a densely populated and heavily modified country over four decades.

Globally, fish have been severely affected by the widespread, chronic degradation of fresh waters, with a substantial proportion of species declining in abundance or range in recent decades. This has especially been the case in densely populated countries with an industrial heritage and intensive agriculture, where the majority of river catchments have been affected by deteriorations in water quality and changes in land use. This study used a spatially and temporally extensive dataset, encompassing 16,124 surveys at 1180 sites representing a wide range of river typologies and pressures, to examine changes in the fish populations of England's rivers over four decades (1980s-2010s). The analyses revealed gradual, nationwide increases in mean fish species richness and diversity across the range of pressure gradients. In the majority of cases, increases were most pronounced in the 1980s, since when any further changes have been comparatively minor, but there were no declining trends across the full time series. There were also temporal, nationwide changes in fish assemblage structure, driven largely by variations in the densities of brown trout Salmo trutta or roach Rutilus rutilus, but no consistent increases in the abundance of sensitive, pollution-intolerant species in response to improvements in wastewater treatment and, consequently, water quality. Although the increases in fish species richness and diversity over the last four decades are encouraging, subtle and contrasting changes in the abundance of a range of species require further investigation, and causal relationships between fish assemblage structure and putative drivers should be modelled at a national scale. This study is the first to examine long-term, nationwide trends in the freshwater fish populations of England, and significantly advances our understanding of the ecological health of rivers in densely populated and heavily modified countries.

Food environmental footprint: Evolution of the countryside species-area relationship (SAR) with new methodologies.

The species-area relationship (SAR) is one of the oldest in ecology, linking the increase in species richness in sampling area. Later, new parameters were incorporated into its equation, such as taxon-specific responses, habitats use by species and species adapted to human-modified habitats, originating the Countryside SAR, a version intended to integrate the life cycle assessment (LCA) methodology, which is still inefficiencies when used to evaluate food production systems. Therefore, we present the first attempt to incorporate into Countryside SAR the minimum land demand parameter for food production, the food environmental footprint - EFP, and improve the use of the method within the agricultural sciences scope. To prepare the EFP, we used land cover data for two types of food systems: agriculture (annual crops), composed of nine types of food; and, livestock (pasture), consisting of meat production. They were later tested in inventories for the Western European broadleaf forest ecoregion (ecocode: PA0445). The most important result observed was that the models responded to variations in production values, resulting in higher impact and a more conservative result when EFP is adopted. But as historically integrating a productivity parameter, or performance of production systems, has been left out of the development of SAR, only the first step has been taken. Therefore, incorporating minimum land demand for food production into the Countryside SAR appears to be a new stage in its development, allowing to generate results that consider the "efficiency" of food production, assuming a more agronomic profile. However, this is still the first attempt to include the EFP in the Countryside SAR, and we believe that our models should still be subject to further evaluation.

A multi-levels analysis to evaluate the toxicity of microplastics on aquatic insects: a case study with damselfly larvae (Ischnura elegans)

Microplastic (MP) pollution prevalent in freshwater environments and jeopardizes the organisms living there. Dozens of studies have been conducted to investigate the harmful effects of microplastics on organisms. However, the most diverse and sensitive aquatic insects are often overlooked, also there is a lack of a comprehensive research exploring the toxicity of microplastics. Here, taking the damselfly larvae (Ischnura elegans) as the subject, we investigated the effects of different concentration levels of polystyrene microplastics (PS MPs) on their physiological characters, behavioristics, metabolomics and transcriptomics, as well as gut microbiome. The results showed that the PS MPs had no significant effects on the body weight and survival rate, but led to behavioral inhibition. Furthermore, expression levels of some metabolites altered, such as nicotinic acid, fumaric acid, and stearic acid. Meanwhile, the pathways related to oxidative phosphorylation and carbon metabolism were upregulated at the transcriptomic level. Moreover, there was a modification of the gut microbial community, with an increase in species richness but a shift towards potentially harmful bacteria. Our findings suggested that exposure to PS MPs affected the overall health of damselfly larvae. Therefore, effective management of MPs to minimize their environmental input is crucial in reducing health risks to aquatic organisms.

МОНИТОРИНГ БИОРАЗНООБРАЗИЯ ЕЛЬНИКОВ ЕВРОПЕЙСКОЙ ЧАСТИ РОССИИ ПОСЛЕ ПРИРОДНЫХ И АНТРОПОГЕННЫХ «КАТАСТРОФ»

We analyzed the main trends of the change in the species richness of plant communities after catastrophic natural (catastrophicwindthrow, fires, large bark beetle outbreaks) and anthropogenic (clear felling) disturbances. The main factor determining the increase in species richness was the intensity of ecosystem disturbance after ca- tastrophes. The greatest disturbance was caused by clear-cut logging, when all timber was removed from the felling area by tractors. Fires also could totally destroy stands and all components of the forest ecosystem. Large- scale wind damage affected only the trees of the upper layer, while all other components of the plant communities were slightly damaged. The bark beetle outbreaks cause the death only of upper layer spruce trees, while the whole forest ecosystem remains unchanged. The degree of disturbance of stands, undergrowth, herb-dwarf scrubs layer, moss cover, litter and soil during the dieback of spruce forests as a result of ‘catastrophes’ determines the degree of vegetation recovery in disturbed areas. We studied the spruce forest in the zone of coniferous-broadleaved forests of the Moscow region, affected by an outbreak of typograph bark beetle.Dynamics of understory plant species richness was fundamentally different after stand salvage logging following beetle outbreaks and in unlogged standswith preserved deadwood. Monitor- ing observations of plant communities during 10 years on permanent sample plots revealed the main feature of the plant species succession after clear felling. For the first six years succession passed through the herb and the shrub stages with a sharp increase in species and structural diversity of plant communities. Only in the forest stage the species composition characteristic of the forest was restored. In the deadwood stand the forest communities was preserved and no differences in the dynamics of species richness of the original undisturbed forest were detected. Only dominance of species in the stand and herb-shrub layer changed. If man don't clear cut dead and wind- damaged areas of spruce forests, it will result in development of mixed forests with increased resistance to pests and forest diseases. Monocultures of spruce forests may be replaced by mixed forests, increasing the diversity of forests.

Long-Term Changes in Bird Communities in the Urban Parks of Mar del Plata City, Argentina

Urbanization is related to the loss of biodiversity and alteration of ecosystem processes. However, long-term changes in the southern hemisphere’s bird communities have been scarcely analyzed in urban areas. The general objective of this work was to analyze changes in bird species richness, diversity, and composition in parks located in the urban and suburban landscapes of Mar del Plata City (Argentina) between 2003 and 2018. Additionally, we aimed to analyze whether these changes were associated with an increase in urbanization or with alterations in the parks’ habitat structure. Tree cover showed significantly lower coverage during 2018. The results showed increased species richness and diversity in all parks by 2018. Rarefaction curves showed that the park bird richness did not differ between the landscapes surrounding parks, but the Shannon and Simpson diversities were higher in parks in suburban landscapes than in parks in urban landscapes. The Shannon and Simpson diversities showed higher values in suburban parks during 2018. However, the diversity values were similar between years in parks in urban landscapes. The species composition was significantly different between landscapes and years. Species turnover was the most predominant pattern of species dissimilarity between landscapes, and species nestedness explained the most dissimilarity between years. Nestedness between years was related to the population increase in many bird species in 2018. In conclusion, we observed differences in the park bird communities between years and landscape types. However, the long-term community changes were not associated with an urbanization increase. Instead, the changes in the local bird community were more related to regional bird species population changes associated with climate warming and increased crop cover.

Transforming Agricultural and Sulfur Waste into Fertilizer: Assessing the Short-Term Effects on Microbial Biodiversity via a Metagenomic Approach.

Fungi and soil bacteria are vital for organic matter decomposition and biogeochemical cycles, but excessive synthetic fertilizer use contributes to soil degradation and loss of biodiversity. Despite this, about 97% of soil microorganisms are unculturable, making them difficult to study. Metagenomics offers a solution, enabling the direct extraction of DNA from soil to uncover microbial diversity and functions. This study utilized metagenomics to analyze the rhizosphere of two-year-old Tonda di Giffoni hazelnut saplings treated with synthetic NPK, composted olive pomace, and an innovative fertilizer derived from sulfur-based agro-industrial waste stabilized with bentonite clay. Using 16S rDNA for bacteria and ITS2 for fungi, Illumina sequencing provided insights into microbial responses to different fertilizer treatments. The results highlighted a significant increase in the abundance of beneficial microorganisms such as Thiobacillus, Pseudoxanthomonas, and Thermomyces, especially when organic materials were included. Additionally, microbial biodiversity improved with organic inputs, as shown by increased species richness (Chao1) and diversity (Bray-Curtis) greater than 20% compared with NPK and unfertilized soils (CTR). These findings emphasize the importance of organic fertilization in enhancing soil microbial health, offering a sustainable approach to improving soil quality and hazelnut productivity.

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

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

Enhanced MTBE removal in fixed-bed bioreactor with iron-modified carriers: Biofilm structure and microbial community

The residue of methyl tert-butyl butyl ether (MTBE) in groundwater poses a great threat to human health and needs to be addressed urgently. An efficient fixed-bed biofilm reactor was constructed by immobilizing MTBE-degrading bacteria Stenotrophomonas, Pseudoxanthomonas and Sphingobacterium on iron-modified activated carbon. The introduction of iron improved the specific surface area, zeta potential and hydrophilicity of the carrier, thus enhancing microbial adhesion. During reactor start-up, iron modification promoted the production of protein-dominated extracellular polymers, increased the biomass loaded on the carrier, and accelerated the formation of thicker (75.4 μm) and denser three-dimensional mesh biofilms. During operation, the iron-loaded reactor retained a thicker biofilm (157.9 μm) with greater stability and biological activity, which facilitated the removal of MTBE. Moreover, the iron-loaded biofilm system promoted the enriched growth of Stenotrophomonas with a higher percentage of MTBE-degrading bacteria (80 %), increased species richness and diversity under adverse conditions, thereby enhancing metabolic capacity and environmental tolerance.

Effects of tree species composition in plantation forest on soil aggregate stability and organic carbon pools in northeastern China

Forest tree species composition influences soil aggregate stability (SAS) and labile organic carbon (LOC) components, which may affect soil organic carbon (SOC) sequestration. Despite the general belief that mixed forests enhance SOC storage, evidence suggests that certain monocultures may outperform mixed forests. Therefore, information on the specific impact of tree species mixing on SOC through SAS and LOC remains limited. This study aimed to investigate the effects of tree species composition on SAS and LOC in 49-year-old monoculture (Larix gmelinii (Lg), Pinus koraiensis (Pk)) and mixed conifer-broadleaf (Larix gmelinii - Fraxinus mandshurica (LF), and Pinus koraiensis - Populus ussuriensis (PP)) stands, and its impact on SOC sequestration. We measured SAS indices (including mean weight diameter (MWD), geometric mean diameter (GMD), and > 0.25 mm water stable aggregate proportion (WSA)), SOC storage, and LOC components (easily oxidized organic carbon (EOC), microbial biomass carbon (MBC), and dissolved organic carbon (DOC)) in 0–40 cm soil horizons during the growing season (June, August, and October). Our results showed that tree species composition significantly influenced SAS and SOC components, with the highest SAS found in the 0–20 cm soil horizon in Pk and PP forests (p < 0.05) (Jun.: MWD Pk: 0.98, GMD Pk: 1.88, WSA Pk: 1.79, MWD PP: 0.98, GMD PP: 1.90, WSA PP: 1.81; Aug.: MWD Pk: 0.99, GMD Pk: 1.85, WSA Pk: 1.77, MWD PP: 0.99, GMD PP: 1.89, WSA PP: 1.81; Oct.: MWD Pk: 0.98, GMD Pk: 1.86, WSA Pk: 1.76, MWD PP: 0.97, GMD PP: 1.83, WSA PP: 1.73) and the highest SOC components in the LF stand (p < 0.05) (soil horizon 0–20 cm: Jun.: SOC: 110.23 g/kg, EOC: 92.81 g/kg, MBC: 1418.39 mg/kg, DOC: 1090.01 mg/kg; Aug.: SOC: 108.46 g/kg, EOC: 79.57 g/kg, MBC: 1369.91 mg/kg, DOC: 1316.11 mg/kg; Oct.: SOC: 109.78 g/kg, EOC: 44.37 g/kg, MBC: 1782.6 mg/kg, DOC: 671.05 mg/kg). Correlation analysis revealed significant relationships between SOC and LOC components (p < 0.05, r EOC = 0.43, r MBC = 0.46, r DOC = 0.17) but not associated with SAS (p > 0.05, r MWD = −0.07, r GMD = −0.07). Tree species composition in plantation stands significantly affects SAS and SOC pools. In conclusion, the positive effect of mixed coniferous and broad-leaved forests on SAS and SOC pools is also contingent upon the tree species identity. The results suggest that targeted selection of tree species could better enhance SAS and SOC pools in plantation than a mere increase in species richness.

Habitat Type-Based Assemblage and Distribution Prediction of Small Mammals and Chigger Mites (Acari: Trombiculidae) in Chuncheon City, Republic of Korea.

While urbanization leads to habitat loss for medium and large mammals, small mammals can survive in fragmented habitats. As they are known to be the primary hosts of chigger mites (Acari: Trombiculidae) that transmit scrub typhus, their habitat can be considered the primary distribution area for chigger mites. This study aims to examine the distribution of small mammals and chigger mites in four habitat types and analyzed species richness, mean intensity (MI), dominance, and infestation rate (IR). A total of six small mammal species were captured, 76.8% of which were identified as Apodemus agrarius. Species richness of small mammals was highest in forests, followed by ecotones, grasslands, and agricultural lands. Apodemus agrarius accounted for 61% of the captures in forests, 80% in ecotones, 84% in grasslands, and 50% in agricultural lands, highlighting its varying dominance across habitat types. The MI of chigger mites was higher in grasslands (215.41 ± 20.70) and ecotones (171.67 ± 30.33) and lower in forests (76.67 ± 32.11). The MI of chigger mites was higher in the fall than that in the spring, and according to the MaxEnt model, they had a narrow, dense distribution in the fall and a wide distribution in the spring. These results suggest that inducing increased species richness of small mammalian hosts by habitat management and vegetation diversification may contribute to a reduction in the MI of chigger mites.

Early Detection of Wild Ungulate Herbivory Cessation in Mediterranean Landscapes Using Hill Numbers as Vascular Plant Diversity Indices

Herbivory by ungulates is a seminal driving force in Mediterranean landscapes, where habitat diversity contributes to supporting high population densities. We investigated the influence of grazing and browsing, primarily by red deer (Cervus elaphus), on herbaceous and woody plant species, using a twin-plot design with herbivory exclusion. The prompt detection of herbivory cessation in vegetation was measured in multiscale plots by calculating Hill’s numbers (0, 1, and 2) as diversity indices over two years. The results revealed an increased diversity gradient by habitats (Pine reforestation→Mediterranean woodland→dehesas of Quercus spp.) with an initial increase in overall species and herbaceous species richness in the fenced plots. Woody vegetation did not change significantly in species richness, or typical or dominant ones. In addition to the early changes detected in the richness of herbaceous species (0Dher), medium–long term variations in woody species (presence and abundance) would represent good indicators of herbivory pressure for a diverse array of Mediterranean habitats.

Plant and soil responses to sediment deposition and nutrient‐enrichment in healthy, deteriorating, and newly created coastal marshes of the Mississippi River Delta

Coastal marshes vulnerable to sea‐level rise may benefit from sediment amendments to increase elevation. However, nutrient‐loading to estuaries may counter elevation gain through reduced root production and/or increased decomposition. Here, we test if belowground plant productivity, root decomposition, and marsh accretion response to nutrient‐loading differs with sediment addition in three marsh types: a healthy intermediate salinity marsh, a deteriorating brackish marsh, and a created marsh in Barataria Basin, Louisiana, United States. In this region, wetland loss is rapid, and a major restoration project is underway to introduce Mississippi River water, sediment, and nutrients to offset marsh loss. Porewater nutrient concentrations, vegetation structure, belowground productivity and decomposition, and accretion rates were measured over 450 days. Experimental nitrate additions yielded high porewater ammonium‐N concentrations in the Deteriorating marsh but had a smaller effect in Healthy and Created marshes. Belowground productivity in the Deteriorating marsh was neutral to negatively affected by nutrient and sediment treatments, whereas positive effects occurred in Healthy and Created marshes. Despite elevation increase from sediment treatments, and substantial effects of nutrient treatments on porewater nutrient concentrations, belowground decomposition and surface accretion rates were not affected by treatments. Sediment deposition increased species richness in the Healthy marsh and added sediment and added nutrients with sediment increased plant height in the Created and Deteriorating marshes, respectively. Over the timescale measured, experimental sedimentation and pulsed nutrient input had few consistent effects on belowground ingrowth, decomposition, or surface accretion. Our findings highlight that response to nutrient pulses are complex and depend on baseline marsh conditions.

Long-term contamination by non-native fish assemblages in a Neotropical floodplain.

Biological invasions are a major threat to biodiversity in species-rich regions. Therefore, it is important to understand mechanisms behind the long-term establishment of non-native fish species in aquatic environments in the Neotropical region. Here, we associated fish biomass, species richness, and the proportion of non-native species (contamination and Kempton's indices) to quantify the non-native pressure over fish biodiversity in lakes and rivers of the Parana River floodplain, seasonally, from 2000 to 2017. We divided species into native and non-native assemblages sampled in spatio-temporal gradients. Temporal trends were examined using linear regressions and generalised additive models. Fish biomass in gillnets increased for both native and non-native fish species, but their Kempton indices were inversely correlated. Extinction of native species occurred locally with biotic differentiation of non-native species in lakes, rivers, and ecosystem contamination. A constant increase in fish biomass resulted in overwhelming biodiversity of non-natives at the end of the time series evaluated. Native biotic resistance to introductions was not detected in deterministic trends. The observed patterns were consistent with previous studies showing native biotic homogenisation and extinction of species in response to biological invasions, landscape fragmentation, and riverine impoundments. Increases in abundance and species richness of non-native fish were the biodiversity drivers that resulted in non-native species outweighing native species in the Parana floodplain.

Impact on Ant Communities by Chemical Pesticides Applied in Controlling the Red Imported Fire Ant (Solenopsis invicta Buren) in the Field.

The red imported fire ant (RIFA, Solenopsis invicta Buren) represents a significant invasive pest in China, exerting extensive negative impacts on ecosystems. The invasion of RIFA not only poses a severe threat to biodiversity within the environment; inappropriate controlling measures can also adversely affect community dynamics. Therefore, while implementing effective management strategies to control the proliferation of RIFA populations, it is imperative to evaluate the potential effects of these measures on the structure of local biological communities to safeguard native biodiversity. This study employs a "two-step method" using dust and bait formulations, respectively, to control RIFA while conducting ecological monitoring to further assess the impact of RIFA population decline on ant communities. The results of RIFA management showed that after post-treatment periods of 28 days, 35 days, and 60 days, the worker ant reduction rates for the three insecticides-0.5% beta-cypermethrin dust, 1.0% hydramethylnon bait, and 0.1% indoxacarb bait-reached approximately 72%, with their efficacy ranked as follows: 1.0% hydramethylnon bait > 0.1% indoxacarb bait > 0.5% beta-cypermethrin dust. By the 60th day of the experiment, the ant nest reduction rates reached their highest values-66.84% for 0.5% beta-cypermethrin dust, 77.89% for 1.0% hydramethylnon bait, and 87.52% for 0.1% indoxacarb bait-with the latter performing the best. Meanwhile, the occurrence level of RIFAs in all three pesticide treatment areas decreased from level III to level I 60 days post-treatment. Following the application of these three insecticides, the RIFA population significantly decreased, leading to an increase in species richness within the ant community. The reduction in RIFA numbers had a positive impact on the restoration of ant community diversity, as evidenced by significant improvements in both diversity and evenness indices. Notably, 0.1% indoxacarb bait was particularly effective in enhancing the ant community diversity and species richness, while 1.0% hydramethylnon bait was more effective in improving community evenness. These findings indicate that the controlling strategy used in this study not only effectively manages RIFA populations but also promotes recovery and contributes to the ecological balance of local ant communities, providing an important reference for future biodiversity conservation efforts.

Reduced canopy cover and development compromises weed suppression by buckwheat in cover crop mixtures

Buckwheat (Fagopyrum esculentum Moench) is a common cover crop typically grown for its rapid establishment and superior weed suppression. One challenge of incorporating buckwheat into crop rotations, however, is its short generation time, which requires in-season management to prevent viable seed production and volunteers in subsequent crops. Mixing buckwheat at reduced seeding rates with other cover crop species is one way for producers to reduce volunteer potential; however, this may compromise weed suppression. To investigate mechanisms behind buckwheat weed suppression and how using buckwheat in mixtures can affect suppression, we collected a series of morphological measurements in buckwheat monocultures and in three, two-way and four, three-way cover crop species mixtures and modeled their response over the growing season. We found that while buckwheat height and relative growth rate were unaffected with increasing species richness, there was a significant reduction in maximum leaf area index (3.75 vs. 2.85 vs. 2.82 cm2 cm-2) in mixture. Buckwheat monocultures provided superior season-long weed suppression compared to mixtures (85% vs. 53% vs. 50%). Principal component analysis showed that increased height and leaf area index values were associated with greater weed suppression. The link between reduced leaf area index and weed suppression in mixtures compared to buckwheat monocultures suggests that the rapid leaf development and canopy cover associated with buckwheat is a key mechanism behind weed suppression. In practice, producers should expect a dilution effect and weed suppression to be compromised when the buckwheat seeding rate is reduced in mixtures.

Loss of Coral Trait Diversity and Impacts on Reef Fish Assemblages on Recovering Reefs.

Understanding patterns of biodiversity change is essential as coral reefs experience recurrent cycles of disturbance and recovery. Shifts in the total cover and species composition of habitat-forming corals can have far-reaching consequences, including shifts in coral functional traits and impacts on local fish assemblages. We surveyed coral and fish assemblages along the southern coast of Hainan Island near Sanya, China, in 2006, 2010, and 2018, during a period with repeated mass bleaching events. We showed that coral biodiversity in this region is in a state of flux, with losses and gains in coral cover and an increase in species richness over time. Despite increasing species diversity, the region suffered a loss of coral trait diversity by 2010, with an incomplete recovery by 2018, owing to declines in species with key habitat-forming traits (e.g., high surface areas and fractal structure) such as corymbose corals. Concurrently, there was an increase in functional redundancy due to the proliferation of the dominant encrusting and massive corals. Coral cover was positively associated with the abundance of reef fish, indicating that the changes observed in coral abundance can impact reef-associated species. These results demonstrate that the slow recovery of coral biodiversity in southern Hainan Island has been hampered by the loss of specific coral traits and highlight the importance of protecting vulnerable coral traits in conservation and management strategies.

Semi-natural habitats are key to breeding bird diversity in intensified vineyard landscapes across Europe

In climatically suitable regions across Europe, vineyards can be the dominant perennial crop type. While many wine-growing landscapes are intensively managed, they may still be an attractive habitat for a wide range of bird species. In this study we investigated how breeding birds in three wine-growing regions in Europe (Germany: Palatinate, France: Bordeaux, Austria: Leithaberg) are influenced by the composition of the landscape, focussing on woody semi-natural vegetation.We recorded bird vocalizations with autonomous sound recorders in 93 landscapes across Europe. Bird species were identified according to their songs and calls. The landscape in a 200-m buffer around the recording points was mapped. In total, we recorded 72 bird species, including species typical for vineyard landscapes such as cirl bunting (Emberiza cirlus), hoopoe (Upupa epops) and turtle dove (Streptopelia turtur). For all three countries we found that an increase in overall woody vegetation in the landscape led to an increase in species richness and altered community composition. Most species were recorded in landscapes with abundant hedges, small woods and tree rows rather than in vineyard-dominated landscapes but e.g. woodlark (Lullula arborea) and linnet (Linaria cannabina) showed an opposite preference.We conclude that in intensively used wine-growing landscapes the ongoing decline in farmland birds and the ecosystem services they provide can be reversed by the reintroduction of semi-natural woody vegetation between vineyards. These in frequently many cases linear structural elements can be established included in the landscape with only small losses in production area.