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The role of human activity in shaping the terrestrial environment has been a core scientific issue of interest across various disciplines. However, it remains unclear whether there are significant differences in the patterns of the anthropogenic impact on the terrestrial environment in terms of spatial and temporal dimensions, and we are yet to identify the underlying factors that have driven it. Here, we present an analysis of sporopollen and geochemical proxies from a section of the Anjiangbei site (AJB) on the Yunnan Plateau, spanning the Ming–Qing period, in order to explore the spatio-temporal variation in the anthropogenic impact on the terrestrial environment in the Lake Dian basin. Integrating the reported multidisciplinary evidence, we aim to reveal the influencing factors of anthropogenic impact. Our results show that there were remarkable differences in anthropogenic impact on the terrestrial environment in the Lake Dian basin between the Late Bronze Age and the Ming–Qing period. Changes in crop vegetation and the forest were all affected by human activity in the Lake Dian basin during the two periods, and were more evident during the Ming–Qing period. The heavy metal pollution in the soil was obvious during the Ming–Qing period. The increase in the intensity of human activity, especially the rise in population, could be attributed to changes in the hydrological environment in the Lake Dian basin during the Late Bronze Age and to geopolitical change during the Ming–Qing period. This study reveals the different patterns in human impact on the terrestrial environment in the Lake Dian basin during the Late Bronze Age and the Ming–Qing period, providing new evidence to enable a deeper understanding of past human–environment interactions on the Yunnan Plateau.

Archaeobotanical studies have largely illuminated spatiotemporal differences in agricultural development across the Loess Plateau. However, the particularities of local agricultural development have not been adequately studied for complex geographical, environmental, and prehistoric contexts. Here, new archaeobotanical data and radiocarbon dating results from 27 Neolithic and Bronze Age sites in Baoji are reported. Combining these data with published archaeobotanical datasets, this study explores shifts (and underlying driving factors) in cropping patterns from the late Neolithic to Bronze Age on the southern Loess Plateau (SLP). Regional geographic, environmental, and climatic factors produced mixed millet-rice agricultural systems in the Guanzhong Plain (GZP) and western Henan Province (WHN) and foxtail and broomcorn millet dry-farming systems in the Upper Weihe River (UWR) from 5800–4500 cal BP. Wheat and barley were added to the agricultural systems of the UWR as auxiliary crops after ~4000 cal BP, while cropping patterns remained largely unchanged in GZP and WHN from 4500–3500 cal BP. Cultural exchanges and technological innovations may have influenced the formation of different agricultural patterns across the three regions (i.e., GZP, WHN, and UWR) from 4500–3500 cal BP. From 3500–2200 cal BP, wheat and barley became increasingly important crops on the SLP, although their importance varied spatially, and rice was rarely cultivated. Spatiotemporal variation in cropping patterns was driven by altered survival pressures associated with climate deterioration and population growth from 3500–2200 cal BP. This process was reinforced by internal social developments, as well as interactions with close northern neighbors, in the Shang-Zhou period.

Fish population fluctuations have been widely documented and are often attributed to climate variability, but little is known about their relationship. This is a barrier that restricts our capacity to understand climate effects on fish fluctuations. Here, we collected published data to conduct a comparative analysis of time series in terms of both scale deposition rate (SDR) and catch to indicate the abundance of anchovy and explored its relationships with climatic and environmental parameters. We first conducted a Spearman correlation analysis to identify the differences in the SDR between sites. Then, we used Generalized Additive Models to evaluate the effects of external forcing at multiple spatial scales (i.e., local and global scales) on the anchovy catches recorded at the California Current Ecosystem (CCE), Humboldt Current Ecosystem (HCE), and Kuroshio Current Ecosystem (KCE). We found that the SDRs at different sites in the same Current Systems are generally consistent, while there are more differences between different systems. We also found that the Pacific Decadal Oscillation index (PDOI), North Pacific index (NPI), North Pacific Gyre Oscillation index (NPGOI), Sea Surface Temperature anomaly (SSTA), and Air Temperature anomaly (ATA) were the most influential factors explaining the variability in anchovy catch for CCE, whereas the NPGOI was the most influential factor for HCE. The PDOI was the best at explaining the variability in anchovy catch for KCE. Our results suggest that anchovy fluctuations in the Pan-Pacific occurred synchronously. These seemingly unrelated events, which occurred thousands of kilometers apart, were actually not isolated. Therefore, we suggest that large-scale climate forcing may activate synchronous fluctuations for anchovy populations at the basin scale, whereas local-scale environmental forces are also responsible for anchovy fluctuations in the “micro-environment”.

Contemporary studies emphasize theoretical and analytical aspects of monitoring water quality within lacustrine settings. The X-ray fluorescence (XRF) core scanner provides the most rapid, non-destructive high-resolution elemental measurements for unprocessed sediments. However, the analytical precision of measured elemental composition may be offset due to water content and inhomogeneities in the physical properties of the sediment. A range of calibration approaches developed specifically for converting XRF scanning intensities to element fractions has been made available. Here, two lake sediment-cores retrieved from southwest China were used to evaluate the performance of various calibration methods. In particular, the influence of sediment properties on XRF scanning intensities was assessed by redundancy analyses (RDA) and the generalized additive model (GAM). The results demonstrate that for fine-grained sediments, the impact of grain size results in only minor deviations in the XRF scanning intensities. Water content of the lake sediment was shown to be the most important factor influencing the XRF scanning intensities, especially for light elements (e.g., Al to Fe). Significant decreases in XRF scanning intensities may occur when sediment water content is greater than 47%. We recommend testing the element fractions obtained via conventional techniques throughout the core and applying the multivariate log-ratio calibration for high-resolution XRF scanning elements within lake sediments.

The Neolithic period witnessed the start and spread of agriculture across Eurasia, as well as the beginning of important climate changes which would take place over millennia. Nevertheless, it remains rather unclear in what ways local societies chose to respond to these considerable changes in both the shorter and longer term. Crops such as rice and millet were domesticated in the Yangtze River and the Yellow River valleys in China during the early Holocene. Paleoclimate studies suggest that the pattern of precipitation in these two areas was distinctly different. This paper reviews updated archaeobotanical evidence from Neolithic sites in China. Comparing these results to the regional high-resolution paleoclimate records enables us to better understand the development of rice and millet and its relation to climate change. This comparison shows that rice was mainly cultivated in the Yangtze River valley and its southern margin, whereas millet cultivation occurred in the northern area of China during 9000–7000 BP. Both millet and rice-based agriculture became intensified and expanded during 7000–5000 BP. In the following period of 5000–4000 BP, rice agriculture continued to expand within the Yangtze River valley and millet cultivation moved gradually westwards. Meanwhile, mixed agriculture based on both millet and rice developed along the boundary between north and south. From 9000–7000 BP, China maintained hunting activities. Subsequently, from 7000–6000 BP, changes in vegetation and landscape triggered by climate change played an essential role in the development of agriculture. Precipitation became an important factor in forming the distinct regional patterns of Chinese agriculture in 6000–4000 BP.

Changing ecological communities in response to anthropogenic activities and climate change has become a worldwide problem. The eutrophication of waterbodies in freshwater and seawater caused by the effects of human activities and nutrient inputs could result in harmful algae blooms (HABs), decreases water quality, reductions in biodiversity and threats to human health. Rapid and accurate monitoring and assessment of aquatic ecosystems are imperative. Environmental DNA (eDNA) analysis using high-throughput sequencing has been demonstrated to be an effective and sensitive assay for detecting and monitoring single or multiple species in different samples. In this study, we review the potential applications of eDNA approaches in controlling and mitigating eutrophication and HABs in freshwater and marine ecosystems. We use recent studies to highlight how eDNA methods have been shown to be a useful tool for providing comprehensive data in studies of eutrophic freshwater and marine environments. We also provide perspectives on using eDNA techniques to reveal molecular mechanisms in biological processes and mitigate eutrophication and HABs in aquatic ecosystems. Finally, we discuss the feasible applications of eDNA for monitoring biodiversity, surveying species communities and providing instructions for the conservation and management of the environment by integration with traditional methods and other advanced techniques.