Climate and human activity are two important factors in regulating organic matter (OM) accumulation in the lake environment. However, when and how anthropogenic impacts have affected lacustrine OM accumulation in southwest China during the late Holocene have not yet been well defined. Here, a 16.3-kyr n-alkane record derived from Erhai Lake was used to trace OM sources and explore their connections to climate and human activity. The n-alkane distributions indicated that the dominant sediment sources shifted from terrestrial and aquatic plants to algae in the late Holocene. OM accumulation was closely related to catchment soil erosion, sediment transport, and deposition processes regulated by climate conditions before 5.0 cal. kyr B.P., following the patterns that stronger monsoon precipitation favoured more terrestrial and less aquatic OM input, and vice versa. From 5.0 to 2.0 cal. kyr B.P., the synchronous downwards trends in terrestrial OM input and precipitation intensity indicated that climate remained a major driving force for OM accumulation. However, sediment sources experienced large-magnitude and centennial-scale oscillations between allochthonous and autochthonous inputs, reflecting early human impacts appeared and lake ecosystems retained the self-regulated ability to recover from the basin-wide early moderate human disturbances. Afterwards, the increased (decreased) OM contributions from terrestrial (aquatic) plants contradicted the weakening monsoon precipitation since 2.0 cal. kyr B.P., indicating a dominant effect of human activities on OM accumulation. This change was accompanied by highly improved algae productivity and gradually elevated lacustrine trophic status, and the lake ecosystem eventually shifted into another state largely deviating from its climate-driven background due to intensified deforestation and agricultural cultivation. Regional comparison indicated that anthropogenic disturbances have temporal differences in southwest China. This study will further improve our understanding of past climate-human-environment interactions in southwest China.
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http://dx.doi.org/10.1016/j.scitotenv.2024.174182 | DOI Listing |
Biomed Microdevices
January 2025
Department of Laboratory Medicine, The Affiliated Hospital of Southwest Medical University, 25 Taiping Street, Luzhou, 646000, Sichuan, People's Republic of China.
Globally, breast cancer is the most frequent type of cancer, and its early diagnosis and screening can significantly improve the probability of survival and quality of life of those affected. Liquid biopsy-based targets such as circulating tumor cells, circulating tumor DNA, and exosomes have been instrumental in the early discovery of cancer, and have been found to be effective in stage therapy, recurrence monitoring, and drug selection. Biosensors based on these target related biomarkers convert the tested substances into quantifiable signals such as electrical and optical signals through signal transduction, which has the advantages of high sensitivity, simple operation, and low invasiveness.
View Article and Find Full Text PDFFree Radic Biol Med
January 2025
Department of Environmental Health, College of Preventive Medicine, Third Military Medical University, Chongqing, 400038, China; Institute of Toxicology, College of Preventive Medicine, Third Military Medical University, Chongqing, 400038, China. Electronic address:
Bisphenol F (BPF) has become a new risk factor for male semen quality, but its specific mechanism is still unclear. Therefore, this study explored the potential mechanism of BPF affecting male semen quality from the perspective of ferroptosis and m6A RNA methylation. In vivo experiments showed that BPF destroyed the structure of seminiferous tubules, reduced the layers of spermatogenic cells, and reduced semen quality in mice.
View Article and Find Full Text PDFJ Environ Manage
January 2025
College of Resources and Environment, Academy of Agricultural Sciences, Southwest University, Chongqing, 400716, China; Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, Southwest University, Chongqing, 400716, China; Chongqing Key Laboratory of Efficient Utilization of Soil and Fertilizer Resources, Southwest University, Chongqing, 400716, China; Key Laboratory of Low-carbon Green Agriculture in Southwestern China, Ministry of Agriculture and Rural Affairs, Southwest University, Chongqing, 400716, China.
Nitrification inhibitors (NIs) are critical to reduce nitrogen (N) leaching losses. However, the efficacy of different NIs can be highly variable across soils and crop types, and a deeper understanding of the mechanistic basis of this efficiency variation, especially in purple soil under vegetable production, is lacking. To enrich this knowledge gap, the impact of different NIs amendment (3,4-dimethylpyrazole phosphate, DMPP; dicyandiamide, DCD; nitrapyrin, NP) on nitrification and the microbial mechanistic basis of controlling nitrate (NO-N) leaching of vegetable purple soil was explored in southwest China.
View Article and Find Full Text PDFInt Immunopharmacol
January 2025
Chemical Injuries Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran.
Introduction: Biomarkers play a crucial role across various fields by providing insights into biological responses to interventions. High-throughput gene expression profiling technologies facilitate the discovery of data-driven biomarkers through extensive datasets. This study focuses on identifying biomarkers in gene expression data related to chemical injuries by mustard gas, covering a spectrum from healthy individuals to severe injuries.
View Article and Find Full Text PDFJ Hazard Mater
January 2025
College of Engineering and Technology, Southwest University, Chongqing 400716, PR China. Electronic address:
The detection of heavy metals in soil is of great scientific significance for food security and human health. However, traditional detection methods are complicated, time-consuming, and labor-intensive. Herein, we developed a novel method using Au@SiO nanoparticles (NPs) and surface microstructure combined with laser-induced breakdown spectroscopy (Au@SiO NPs-SMS-LIBS) for the rapid detection of lead (Pb), chromium (Cr), and copper (Cu) in soil samples.
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