环境科学与生态学最新文献

Many vegetation phenological models predominantly rely on temperature, overlooking the critical roles of water availability and soil characteristics. This limitation significantly impacts the accuracy of phenological projections, particularly in water-limited ecosystems. We proposed a new approach incorporating soil enthalpy—a comprehensive metric integrating soil moisture, temperature, and texture—to improve phenological modeling. Using an extensive dataset combining FLUXNET observations, solar-induced fluorescence (SIF), and meteorological data across the Northern Hemisphere (NH), we analyzed the relationship between soil enthalpy and vegetation phenology from 2001 to 2020. Our analysis revealed significant temporal trends in soil enthalpy that corresponded with changes in leaf onset date (LOD) and leaf senescence date (LSD). We developed and validated a new soil enthalpy-based model with optimized parameters. The soil enthalpy-based model showed particularly strong performance in autumn phenology, improving LSD simulation accuracy by at least 15% across all vegetation types. For shrub and grassland ecosystems, LOD projections improved by more than 12% compared to the temperature-based model. Future scenario analysis using CMIP6 data (2020–2054) revealed that the temperature-based model consistently projects earlier LOD and later LSD compared to the soil enthalpy-based model, suggesting potential overestimation of growing season length in previous studies. This study establishes soil enthalpy as a valuable metric for phenological modeling and highlights the importance of incorporating both water availability and soil characteristics for more accurate predictions of vegetation phenology under changing climatic conditions.

Riverine pollution is an increasing threat to ecosystem integrity and economic development, thus a need for effective monitoring to guide the management of ecosystem health. Opportunely, aquatic macroinvertebrates have been proven to indicate the health status of the rivers. However, there is scanty information about their use in Rwanda. This study used macroinvertebrates to assess the water quality of the Nyabarongo and Akagera Rivers following the Tanzania River Scoring System (TARISS). The study was carried out between May 2023 and March 2024 and covered 13 sampling sites. Macroinvertebrates were collected using a kick sampling method while water samples were collected following standard methods for measuring water properties. Sites were clustered, and multivariate methods were used to assess dissimilarities in taxa distribution. Further, the Focal Principal Component Analysis (FPCA) was performed to assess the association of macroinvertebrates with water physico-chemical parameters. Collected macroinvertebrates belonged to 34 families dominated by Chironomidae, Baetidae, and Culicidae. The TARISS metrics (mean ± standard deviation) indicated a score of 44.53 (± 2.69), a taxa number of 11 (± 0.6), and an average scope per taxa (ASPT) of 4.07 (± 0.8). Dissolved oxygen had a significant positive influence on the distribution and abundance of the Libellulidae family. Conversely, dissolved oxygen and electric conductivity had a significant negative relationship with the Caenidae and Aeshnidae families, respectively. The low values of the TARISS metrics portend the poor water quality of the Nyabarongo and Akagera Rivers. Thus, management practices and regular biomonitoring are recommended to ensure that the ecosystem health of these rivers is maintained.

S. The spread of impermeable surfaces in urban coastal areas increases runoff, carrying pollutants that degrade surface water quality and impact the stress responses of coastal fauna. This study investigated oxidative stress and gonad health in male and female Callinectes amnicola (blue crabs) from urban and suburban regions of Lagos Lagoon. Gonadal damage in the crabs was linked to estrogenic metals (Cu, Zn, Pb, Cd) and antioxidant responses (MDA, GSH, GPx, CAT, and SOD). Urban male crabs showed higher oxidative stress, with elevated MDA and lower GSH and CAT levels, alongside regressive gonadal changes due to increased Pb, Cd, and Zn exposure. Suburban crabs, however, displayed more intersex conditions (ovotestes) correlated with elevated Cu levels in lagoon sediment. These results highlight severe testicular disruption in urban males and ovarian dysgerminomas in suburban females, indicating a sex-specific impact of pollution on reproductive health. The study identifies two primary reproductive toxicity risks: (1) male testicular damage and regressive lesions in urban crabs, caused by increased lipid peroxidation and oxidative stress, and (2) female endocrine disruption, with ovotestes in suburban populations potentially leading to nonviable follicles. These findings emphasize that urban blue crabs face significant risks across both sexes, while suburban populations are more affected by female-specific risks. The study underscores the need for targeted environmental management to address the different stressors impacting these populations.

Graphical abstract

This study examines the spatial and temporal variability of precipitation seasonality across Serbia using various seasonality indices. The research focuses on understanding the intra- and inter-annual variability of precipitation regimes over two sub-periods: 1946–1984 and 1985–2023. For this purpose, monthly precipitation data from 24 synoptic stations across Serbia were analyzed using seasonality indices such as the General Seasonality Index ((overline{SI})), Individual Seasonality Index (SI_i), Mean Individual Seasonality Index ((overline{{SI_{i} }})), and Replicability Index (RI)). The results shown on the SI maps indicate a more irregular rainfall distribution during the first sub-period, with a noticeably higher seasonality in the northern part of Serbia. The mean SI_i shows an increasing gradient from southwest to northeast, with the highest variability shifting from the central and southeastern parts (1946–1984) to the northern and eastern parts of Serbia (1985–2023). Minimum values reveal a shift from a “very equitable” regime in the first sub-period to “equitable with a definite wetter season” in the second, while maximum values generally decreased. RI values remain low across Serbia, reflecting significant variability in precipitation regimes.