Search Results (318)

Landscape simplification resulting from agricultural intensification threatens biodiversity and ecosystem services on arable land. Semi-natural habitats, such as flower strips, can mitigate these effects by providing habitat and resource diversity and by modifying the microclimate at the agricultural landscape scale. As effective natural enemies in arable fields, ground beetles (Carabidae) play a key role not only in pest regulation, but also in weed control through seed consumption. The study found that FS serve as crucial habitats supporting Carabidae—characterized by a higher Shannon–Wiener index—and foster the presence of rare species absent from adjacent wheat and rapeseed monocultures. Unlike field crops, flower strips exhibit greater evenness in ground beetle community structure, indicating higher ecological stability and superior environmental quality. The research confirmed significant seasonal fluctuations in Carabidae abundance, particularly pronounced in flower strips; an increase in numbers was recorded during May and June in both years of observation, confirming that FS act as stable habitats for these insects. Full article

Urban blue–green spaces (UBGSs) are critical for biodiversity, yet our understanding of how plant diversity in these spaces responds to urbanization across different UBGS types remains limited. Here, we investigated plant communities in four sampled UBGSs along an urban gradient in the Minjiang River Basin, China. Because each blue–green space type is represented by a single site, all comparisons are site-specific and descriptive. Using species richness (S), the Shannon–Wiener index (H′), Pielou’s evenness index (J′), frequency (F), and importance value (I.V.), we described whether taxonomic composition and diversity patterns differed among the four sampled sites. Across all sites, based on 615 species records, angiosperms dominated (92.6%), and cosmopolitan families (e.g., Asteraceae, Poaceae, Fabaceae) were ubiquitous, consistent with a strong regional species pool influence. However, our cross-site comparison showed a contrasting pattern: the near-natural Baihetan National Wetland Park showed the highest S (12.87) but low evenness (0.49), whereas the intensively managed Huoshui Park, with the lowest richness (9.67), achieved the highest evenness (0.68). Further, a discordance between F and I.V. rankings was observed in the managed site, where ornamental species showed high spatial coverage but low I.V. ranks. We report this rank discordance only as an observational finding, not as a proven metric or indicator. This discordance suggests that richness alone may not fully capture community structure, though its diagnostic value remains unverified. We interpret these contrasting richness–evenness patterns from the four sampled sites. Because site identity is confounded with management intensity, habitat area, and landscape context, no causal attribution to ecological or anthropogenic factors can be made. Evenness and species richness showed different site-to-site patterns, but this association remains observational. We hypothesize that a resilient urban biodiversity network could combine complementary nodes, with large natural wetlands as species-rich sites and constructed parks as structurally balanced units, rather than pursuing a single diversity target. This study provides preliminary insights that may inform planning considerations under Chengdu’s Park City initiative, but these suggestions should be viewed as hypotheses requiring further validation rather than as established management guidelines. The proposed network approach, while conceptually appealing, requires empirical testing through replicated studies before it can be considered for broader application. Full article

Saxicolous lichens are crucial elements of alpine ecosystems and are involved in soil formation, rock weathering, nutrient cycling, and environmental monitoring. However, little is known about their distribution patterns and diversity on the eastern Pamir Plateau of China. This study looked at the variety and elevational distribution of saxicolous lichens in China’s eastern Pamir Plateau’s Taxkorgan Nature Reserve. Six transects spanning an elevational range of 3500–4500 m were used for field studies in July and August of 2025. Stratified sampling was used to gather lichen specimens, which were then identified by morphological, anatomical, chemical (thin-layer chromatography), and molecular investigations. Lichens communities’ similarity across altitudes was evaluated using Sørensen’s index, and diversity indices such as Simpson, Shannon–Wiener, and Pielou’s consistency were computed. A total of 69 saxicolous lichen species from 12 families and 27 genera were identified. With 95.6% of all species, crustose lichens predominated, whilst foliose and fruticose forms were uncommon. Acarosporaceae and Megasporaceae were the most species-rich families, accounting for over half of total recognized species. In the study region, Aspicilia and Acarospora dominated at the genus level. Saxicolous lichen species richness exhibited a unimodal elevational pattern, peaking at 4101–4300 m with pronounced community turnover across altitudes, as supported by Sørensen similarity values (0.253–0.561). Additionally, substrate type affected lichen distribution, with siliceous rocks hosting richer lichen communities than calcareous substrates. In general, the richness and distribution of saxicolous lichens in the alpine ecosystems of the eastern Pamir Plateau are mostly determined by elevation and rock type. This work provides essential baseline data for lichen biodiversity in the region and highlights the potential use of lichens as bio-indicators for monitoring environmental change in high-mountain ecosystems. Full article

Centella asiatica (L.) Urb., a perennial herb of the Apiaceae family, is an important medicinal plant with diverse therapeutic applications. In this study, we integrated phenotypic evaluation, SSR markers, and HPLC fingerprinting to assess the diversity of 24 C. asiatica accessions collected from Yunnan Province, China. Considerable phenotypic, genetic, and biochemical diversity was observed. The Shannon–Wiener index ranged from 2.20 to 3.14 for qualitative traits. Principal component analysis identified five components accounting for 82.54% of the total phenotypic variance, with leaf morphology as the primary determinant. Q-type cluster analysis grouped the accessions into five phenotypic clusters. Transcriptome analysis revealed 16,799 SSR loci, with dinucleotide repeats as the most frequent motif (44.31%). UPGMA clustering based on SSR markers delineated five genetic groups that correlated with geographic origin, with accessions from the two northernmost sites forming a distinct cluster. HPLC fingerprints identified 16 common peaks, among which five major bioactive constituents—madecassoside, asiaticoside, kaempferol, madecassic acid, and asiatic acid—were quantified. The total content of these five compounds varied markedly among accessions (4.09–20.18 mg·g⁻¹), with the highest found in Zhaoyang (S5). Most accessions exhibited high chemical similarity (>0.9), except for Yiliang (S12), which displayed a distinct profile. The partial correlation between SSR-based classifications and geographic origin, together with the inconsistency between phenotypic and chemical groupings, indicates that morphological variation is shaped by both environmental factors and complex genetic regulatory mechanisms. These findings provide a scientific basis for germplasm conservation, selective breeding, and the sustainable utilization of C. asiatica. Full article

Soil meso- and micro-fauna are key components of forest soil ecosystems, but the effects of converting natural forests to monoculture or mixed plantations on their communities remain unclear. This study compared soil meso- and micro-fauna communities in monoculture (broad-leaved and coniferous) and mixed plantations converted from secondary forests in Northeast China. Results showed that monocultures significantly altered faunal community composition and reduced diversity, whereas mixed plantations maintained similar abundance and diversity to secondary forests. For instance, broadleaf monocultures exhibited a 15–23% lower Shannon–Wiener diversity index, while coniferous monocultures displayed a 28–35% reduction in soil faunal abundance. Notably, different taxonomic groups responded inconsistently to stand type conversion: Oribatida (58.8–72.5% of total individuals) varied significantly among stands (p < 0.001), whereas Collembola (18.8–31.4%) was more affected by season. The community composition was significantly correlated with understory plant diversity/coverage and soil C/N ratio, while α-diversity was mainly driven by total nitrogen. Our findings reveal that mixed plantations, instead of monocultures, are more effective for soil biodiversity conservation, which offers sustainable strategies for forest management. Full article

Grazing disturbance strongly affects grassland ecosystem structure and function, but its impacts on soil protist communities across vertical soil profiles remain unclear in alpine grasslands. We investigated soil protist community composition, alpha diversity, and their relationships with environmental factors under four grazing intensities (no grazing, light, moderate, heavy grazing) at three depths (0–10, 10–20, 20–30 cm) on the eastern Qinghai–Tibet Plateau. Our results showed that grazing significantly altered the relative abundance of dominant protist orders, including Pyrenomonadales, Kinetoplastida, and Amoebida. The Shannon–Wiener and Pielou indices of protists decreased significantly with increasing soil depth, while grazing mainly reduced the Margalef index. Soil total nitrogen, bulk density, and pH were the dominant factors shaping soil protist community structure. Overall, soil protists were more sensitive to soil depth than grazing intensity. These findings improve our understanding of vertical protist distribution under grazing disturbance and provide a scientific basis for sustainable grassland management. Full article

This study investigates the relationship between tree species diversity and soil quality in natural Pinus massoniana Lamb. forests, providing a scientific basis for the sustainable management of natural stands and the establishment of plantations. Located in Ganzhou City, Jiangxi Province, China, a subtropical region, the study focuses on natural P. massoniana forests. The Patrick richness index and Shannon–Wiener diversity index were each classified into three levels—low, medium, and high—to analyze how soil physicochemical indicators vary across these diversity levels. A minimum data set of key soil indicators was established to evaluate soil quality. Linear and nonlinear scoring functions were used to compare the relationships between the total data set and minimum data set-derived soil quality indices, and the most suitable scoring function for this study was selected. An obstacle factor diagnosis model was applied to identify the factors limiting soil quality improvement under different diversity levels. The results showed that (1) in the 20–40 cm soil layer, soil water content, maximum water-holding capacity, and total porosity significantly increased with rising Patrick richness and Shannon–Wiener diversity levels. (2) With increasing Patrick richness and Shannon–Wiener diversity levels, organic matter and total nitrogen in the 0–20 cm soil layer, as well as total potassium, available nitrogen, and pH in both the 0–20 cm and 20–40 cm soil layers, showed significant upward trends. In contrast, total phosphorus in both layers significantly decreased. Furthermore, available phosphorus in both layers significantly declined as Patrick richness increased. (3) The minimum data set based on the nonlinear scoring function can effectively substitute for the total data set (r = 0.791, R² = 0.63), showing better applicability for assessing soil quality changes in natural P. massoniana forests. Additionally, the soil quality index in the 0–40 cm soil layer significantly increased with rising Patrick richness levels. (4) At different Patrick richness levels, bulk density had the greatest impact on soil quality in the 0–40 cm soil layer, while organic matter had the least. A comprehensive analysis shows that there is a positive correlation between tree species diversity and soil quality in natural P. massoniana forests. In P. massoniana plantation practices, a near-natural management approach should be adopted to create relatively species-rich and complex coniferous and broad-leaved mixed stands, which is conducive to improving soil quality. Full article

Background: The Gansu Heihe Provincial Nature Reserve harbors rich plant and animal resources, yet its coleopteran fauna has remained taxonomically and ecologically uncharacterized. To address this gap, we conducted the first systematic survey of beetle diversity across four representative transects—Youcaigou (I), Zhugou (II), Loufangya (III), and Sigou (IV)—and assessed variation in community structure using the Shannon–Wiener diversity index, Margalef richness index, Berger–Parker dominance index, Pielou evenness index, and Jaccard similarity coefficient. Results: A total of 131 species belonging to 108 genera and 22 families were identified, establishing a comprehensive baseline of beetle diversity for the reserve. Cerambycidae was the most species-rich family (27 species), while Lampyridae, Staphylinidae, and Anobiidae were each represented by only a single species, reflecting marked unevenness in family-level composition. Diversity and community structure differed substantially among transects: Transect II showed the highest Shannon–Wiener diversity index and Pielou evenness, Transect III the lowest diversity, and Transect IV the greatest dominance by a few species, while species richness declined in the order I > II > III > IV. Zoogeographic analysis revealed that widely distributed (Cosmopolitan) species predominated (83 species; 63.36%), with Palaearctic (21 species; 16.03%) and Oriental (27 species; 20.61%) elements also well represented, underscoring the reserve’s position at a key biogeographic transition zone. Within China, North China faunal elements were most prevalent (75.94%), with the North China–Northeast China distribution group alone accounting for 54.20% of species, whereas nationally widespread species comprised only 9.16%. Conclusions: This study provides the first systematic record of coleopteran diversity in the Gansu Heihe Provincial Nature Reserve, enriching the region’s biodiversity inventory and offering reference data for future insect monitoring and forest conservation. Further multi-seasonal, method-diversified surveys are needed to achieve a complete faunal inventory. Full article

Biological invasions and environmental gradients are major drivers of biodiversity change in wetland ecosystems, but their associations on native plant diversity in Central Asian riverine wetlands remain poorly understood. We surveyed 158 wetland plant communities across 54 transects in the Ertix River Basin to examine how environmental gradients (elevation, mean annual temperature [MAT], and mean annual precipitation [MAP]) and non-native plant establishment jointly related to native plant importance values and alpha diversity indices. Non-native plants were classified according to invasion stage—non-naturalized, naturalized, and invasive—to elucidate how the associations between alien plants and native communities shift dynamically along the invasion continuum. Elevation emerged as the dominant predictor, explaining 82% (individual R² = 0.15) of the variance in native species richness and 63.37% (individual R² = 0.1) of the variance in the Shannon–Wiener diversity index, while MAT and MAP were not retained as significant predictors in the optimal models. Native plant importance values, richness, and diversity all increased with elevation. Unexpectedly, naturalized plant richness and abundance were positively associated with native diversity metrics, contrasting with the negative associations of all non-native categories (non-naturalized, naturalized, and invasive) on native importance values, partly reflecting the compositional nature of this metric. Our results reveal positive co-occurrence patterns between early-stage naturalized species and native species, but native dominance may eventually decline as invasion intensity increases. These findings highlight the importance of considering invasion stage when predicting wetland biodiversity responses to biological invasions under environmental heterogeneity. Full article

Revealing scale effects and the mechanisms underlying the relationships between plant species and functional diversity is crucial for understanding the stability of desert ecosystems and formulating multiscale conservation strategies. In this study, the spatial patterns of plant species and functional diversity in the Gurbantunggut Desert were analysed via multiscale grid sampling. The results indicated that (1) both species diversity and functional diversity indices exhibited high spatial heterogeneity. At the small scale (10 m × 10 m), the values of the Shannon–Wiener and Pielou indices for fixed dunes were higher in the south than in the north. At the medium and large scales (20 m × 20 m and 50 m × 50 m, respectively), the index values were highest in the southwest, with generally greater values in the south than in the north. For semifixed and mobile dunes, the Shannon–Wiener and Pielou index values exhibited an east-high–west-low pattern at the 10 m × 10 m scale. This differentiation decreased with increasing scale, with the highest values observed in the northeast and southwest at the 50 m × 50 m scale. The spatial differentiation in functional diversity indices (Rao’s second-order entropy index and functional evenness index) exhibited distinct characteristics across the different dune types. (2) The spatial variation in all the diversity indices monotonically decreased with increasing scale, with the variance in the species diversity indices indicating the following order: Shannon–Wiener index > Pielou index > Simpson index. (3) The relationships between species richness and diversity indices exhibited significant scale dependence. At the small and medium scales, species richness was significantly positively correlated with the Shannon–Wiener index, Simpson index, and Rao’s quadratic entropy index and significantly negatively correlated with the Pielou evenness index and functional evenness index. However, at the large scale, none of these correlations were significant. (4) The species diversity indices and Rao’s quadratic entropy index were significantly positively correlated at the small and medium scales (p < 0.01), whereas a significant positive correlation with the functional evenness index was observed only at the 10 m × 10 m scale (p < 0.01). At the larger scale, these correlations became insignificant. In fixed dunes, areas of high Simpson index values exhibited a spatially complementary distribution with areas of high Shannon–Wiener index and Pielou index values, providing evidence for the combined effect of local processes such as competitive exclusion and dispersal limitation. Through comprehensive multiscale analysis, this study revealed the mechanisms underlying the scale-dependent relationships between plant species and functional diversity, thereby providing a theoretical basis for protecting and restoring desert biodiversity. Full article

Alpine shrub meadows on the Qinghai–Tibet Plateau are key warm-season pastures that support pastoral production and ecosystem stability in fragile high-elevation regions. Due to low temperatures, short growing seasons, and slow vegetation recovery, these pastures are highly sensitive to inappropriate grazing management. However, the effects of different grazing–rest time configurations on plant community composition and leaf functional traits in alpine shrub meadows remain insufficiently understood. In this study, we evaluated five grazing treatments in an alpine shrub meadow in Sunan County, central–eastern Qilian Mountains: 10 days grazing–20 days rest (T1), 15 days grazing–15 days rest (T2), 20 days grazing–10 days rest (T3), continuous grazing (CG), and grazing exclusion (CK). In the third year of treatment implementation, we measured the community diversity, species importance values, and leaf functional traits of four dominant species: Elymus nutans, Carex tibetikobresia, Oxytropis kansuensis, and Bistorta vivipara. T1 and T2 significantly increased species richness, Shannon–Wiener diversity, and Simpson diversity compared with CG and CK. NMDS and PERMANOVA further showed significant differences in overall community composition among grazing treatments. Grazing generally reduced the leaf length, leaf width, and leaf area, whereas T2 showed relatively stronger leaf recovery among grazing treatments. Specific leaf area, specific leaf weight, and leaf length–width ratio showed higher variability and calculated plasticity than leaf thickness and leaf dry matter content, suggesting that resource-acquisition and morphological traits were more responsive to grazing than conservative structural traits. The coefficient of variation of leaf traits was positively associated with the plasticity index, although this association should be interpreted cautiously because both indices were calculated from the same underlying trait dataset. Overall, under the conditions of this three-year, single-site experiment and a target moderate grazing intensity, the 15-day grazing–15-day rest regime performed best among the tested treatments. This regime may provide a practical reference for rotational grazing management in similar warm-season alpine shrub meadows, but its broader applicability requires further validation across different grassland types, grazing intensities, climatic conditions, and longer monitoring periods. Full article

Vegetation restoration is an effective measure to improve soil carbon storage in rocky desertification areas. However, the underlying mechanisms driving differences in soil carbon storage among different vegetation types remain unclear. In this study, we selected four typical vegetation types (monospecific broadleaf plantation, mixed conifer–broadleaf plantation, monospecific coniferous plantation, and natural shrubland) from the comprehensive control zone for moderately rocky desertification of Xuyong County in the Chishui River Basin. We investigated the effects of vegetation patterns on soil carbon storage through tree layer functional traits, tree diversity, shrub layer functional traits, shrub diversity, and soil fungal/bacterial diversity. The results showed that soil carbon storage was highest in monospecific broadleaf plantations, followed by mixed conifer–broadleaf plantations, then natural shrubland, and it was lowest in monospecific coniferous plantations. Significant differences were mainly observed in the 0–10 cm and 10–20 cm soil layers, while no significant difference was found in the 20–30 cm layer. Tree layer community-weighted mean of leaf nitrogen content, soil fungal Shannon–Wiener index, and shrub layer community-weighted mean of specific leaf area were the core positive drivers of soil carbon differentiation. Among these, tree layer community-weighted mean of leaf nitrogen content was the most important factor, whereas the regulatory effect of shrub layer community-weighted mean of specific leaf area intensified with increasing soil depth. Furthermore, tree layer community-weighted mean of leaf nitrogen content and shrub layer community-weighted mean of specific leaf area not only directly promoted soil carbon accumulation but also indirectly promoted it by enhancing soil fungal diversity. In contrast, the effects of tree and shrub layer diversity and soil bacterial diversity were negligible. This study demonstrates that increasing soil carbon storage in rocky desertification ecosystems depends on the direct effect of soil fungal diversity, as well as the direct effects of tree and shrub layer functional traits and their indirect effects via regulating soil fungal diversity. We recommend that in moderately rocky desertified areas, priority should be given to tree species with high leaf nitrogen content; on sites unsuitable for afforestation, promoting natural shrublands with high specific leaf area can effectively enhance carbon sequestration capacity. Full article

To investigate the relationship between fishery resources community structure (mainly fish and crustaceans) and environmental factors in the artificial reef waters off Nanri Island, surveys were conducted in November 2021, 2022, and 2023. Shannon–Wiener diversity index (H′), Margalef richness index (D), Pielou evenness index (J′), and resource density index (RD) were employed to characterize the community structure. From 2021 to 2023, DO and petroleum hydrocarbons exhibited significant interannual variation (p < 0.05), whereas DIP, DIN, and SS showed highly significant interannual variation (p < 0.01). Spatially, DO, COD, DIN, and petroleum hydrocarbons varied more than other factors. Both diversity and richness indices rose over the study period, with mean H′ rising from 1.693 to 1.942 and mean D from 2.107 to 2.474. The evenness index (J′) declined in 2022 but then increased to 0.787. In contrast, the resource density index (RD) dropped sharply in 2022 (107.2) and partially recovered in 2023 (155.4), though it remained below the 2021 level (218.5). Redundancy analysis revealed that five environmental variables (DIP, DIN, petroleum hydrocarbons, SS, and DO) primarily shaped the fishery resource community structure in the artificial reef area. This study provided reference data for artificial reef management and sustainable fishery development. Full article

Weed competition, persistent seed banks, and management costs can limit crop productivity in organic farming. A two-year field experiment was conducted in southern Finland to evaluate the effects of pea (Lathyrus oleraceus Lam.), oats (Avena sativa L.), and camelina (Camelina sativa (L.) Crantz.), grown as pure stands and as three-crop mixtures at varying seeding densities, on weed diversity and suppression. The seeding densities (%) were 50:20:30 and 33:33:33 of the pure stand density of pea, oats, and camelina in 2022 and 50:50:50 and 33:33:33 of the pure stand density in 2023. Weed diversity was assessed at five sampling times, species were identified and analyzed for biomass, richness, Shannon-Wiener index (H), evenness, and dominance. Weed diversity and suppression varied with crop composition, growth stage, and seasonal conditions. In 2022, the 33% mix had the highest H (2.22) and evenness (0.77), enhancing weed suppression while controlling dominance. In 2023, pure oats had the highest H (1.65) and evenness (0.87), and pure peas had the lowest H (1.41) and evenness (0.67). Although pure oat stands provided the strongest weed suppression, crop mixtures enhanced species diversity and evenness, suggesting potential for more balanced weed management in organic systems, with short-term results indicating potential benefits for weed control. Full article

Cooling water systems of coastal nuclear power plants in China are frequently threatened by blockages caused by marine organisms. However, long-term studies on macrobenthic community dynamics and their associations with environmental factors are scarce, limiting the precise prevention of such blockage risks. This study conducted quantitative monitoring of macrobenthos and synchronous measurement of water environmental factors at 24 sampling stations in three functional areas (water intake, harbor basin, and drainage outlet) adjacent to the Northeast Fujian NPP from 2018 to 2024. Community structure characteristics were analyzed using the Shannon–Wiener and Margalef indices. The Grappler Method Risk Index (GMRI) was employed to screen species at risk of blocking cooling water systems, and the Mantel test and random forest models were applied to explore the associations between the macrobenthic community and environmental factors. A total of 161 macrobenthic species were identified. Polychaetes (71 species, accounting for 44.1%) were the absolute dominant group, followed by crustaceans (35 species) and Mollusks (30 species). The interannual fluctuation range of the polychaete proportion was 41.1–57.8%, reaching a peak in 2023. There were significant differences in community structure among different areas (PERMANOVA, p < 0.05), with the largest inter-regional difference in 2024 (R² = 0.36). The annual average number of species (9 species), density (155.25 ind./m²), and biomass (29.58 g/m²) in the drainage outlet were higher than those in the water intake and harbor basin. The GMRI identified Protankyra bidentata (spiny sea cucumber, GMRI values of 50.67% to 64.98% from 2019 to 2023) and Actiniaria sp. (sea anemone, a GMRI value of 54.63% in 2021) as medium-risk species for cooling water system blockage, while most other organisms were classified as low risk or extremely low risk. The Mantel test and random forest analysis confirmed that nitrogen nutrients (NO₃⁻) and phosphorus (PO₄³⁻) were significantly positively correlated with the polychaete community. Furthermore, NO₃⁻ and NH₄⁺ each explained 13.66% of the variation in the diversity index (H′), serving as key factors driving community structure. This study demonstrates the co-dominance of thermal and nutrient drivers in shaping macrobenthic communities over a multi-year scale, and identifies specific, morphologically suited taxa as potential blockage risks. The findings provide a scientific basis for targeted risk-species monitoring and support the integration of long-term ecological data into NPP cooling water system security management. Full article