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The balance between the burial of biospheric organic carbon (OC bio) in the ocean and the oxidation of rock-derived organic carbon across landscapes (OC petro) helps to regulate atmospheric CO 2 and O 2 over geological time. However, we lack reconstructions of these processes over the timescales necessary to properly understand the drivers and feedbacks operating. Here we use a sediment core from the Zhuoshui River delta in Taiwan, which receives sediments from a rapidly uplifting and eroding catchment, to reconstruct the variations in OC content and radiocarbon composition since the Last Glacial Maximum (LGM). We find that the export of OC bio and the oxidation of OC petro are both modulated by climate-driven changes in physical erosion and temperature. During cold and dry periods, such as the LGM and the Younger Dryas (YD), shallow erosion and low temperature enhanced the preservation of OC bio in the biosphere in catchment, while deep erosion and high temperature during warm and wet periods, such as the Holocene, favored the dilution and degradation of OC bio. The weathering intensity of OC petro (ω) was inversely related to physical erosion, suggesting a lower intensity of oxidation during the Holocene period while the overall oxidation flux was enhanced. This suggests that the degree of weathering was primarily controlled by physical erosion. We propose a proxy to estimate the ratio of fluxes of OC bio export and OC petro oxidation, and show that the net balance between these two processes shifted from a carbon sink during the late deglacial period to a carbon source during the mid-late Holocene. Our study reveals that with CO 2 rise, a warmer and wetter climate would promote the exposure and oxidation of OC petro by erosion in this mountain range, leading the organic carbon balance towards a CO 2 source to the atmosphere. • Erosion and temperature control carbon dynamic in erosive setting. • Cold, dry periods boost carbon preservation. • Warm, wet climate shifts mountains to carbon sources. [ABSTRACT FROM AUTHOR]

[Display omitted] • An accurate simulation on rice growth stages enhances precision agriculture. • ANN and GEP showed better performance in simulating rice growth rate than REG. • The GEP-Tr all model was recommended due to the model applicability and reliability. • The developed Python-based GEP-Tr all rice growth rate modeling code was provided. Rice growth rate prediction is crucial to achieve precision agriculture. In this study, growth data from three different rice cultivars at two different climate regions in Taiwan were used to calculate the rice growth rate (Gr) in key growth stages. A total of 10,246 Gr data from 95 cultivations were used to assess the feasibility of simulating rice growth rate from ambient temperature by regression algorithm (REG), artificial neural networks (ANN) and gene-expression programming (GEP). Simulation was carried out for each algorithm using ambient temperature and growing season as input variables for the entire life cycle of rice (Tr all) either as one continuous growth period or as the sum of four distinctive growth stages (Tr 1~4). The results showed that the model output from Tr 1~4 are more accurate than Tr all. However, simulation errors in the transitional stages occurred when the growth rate at different stages was modelled separately. Artificial intelligence based nonlinear models were more accurate than the regression model and ANN generally exhibited better performance than other two models. Compared with REG, the root mean squared error (RMSE) and mean absolute error (MAE) of averaged error-in-days for the whole growth period decreased by 41.38% and 42.81% in ANN and 30.14%, and 31.21% in GEP. Considering the potential errors in the transition stages and the high hardware demand for ANN, the GEP-Tr all model is recommended for the rice growth rate modeling. [ABSTRACT FROM AUTHOR]

We report on the near-surface (< 500 m) seismic structure (Vp, Vs, and Vs anisotropy) of Taiwan using the empirical Green's functions of body waves between vertical station pairs at 60 borehole sites. The near-surface anisotropy in metamorphic rocks and Miocene or older sedimentary strata are mostly categorized as orogeny-parallel anisotropy (OPA), and sites exhibiting stress-aligned anisotropy (SAA) are located in areas with late Quaternary sedimentary deposits or in alluvial coastal plains. The results show that there is a significant variation of the anisotropy strength even within the same geological unit. Since all the major geological units of Taiwan are well sampled by borehole arrays, and drilling data for 52 sites are available, this provides a unique opportunity to investigate the geological implications of strong variations in near-surface anisotropy. The investigation indicates that (1) near-surface anisotropy caused by structural fabric is generally stronger than that resulting from the alignment of stress-induced open cracks, (2) SAA strength in sedimentary rocks, igneous rocks, and gravel sediments is generally higher than that in fine-grained sediments, and (3) the sites with the strongest OPA (> 30%) are located in mountain ranges and the mean OPA strength of these sites is significantly higher than that of foothills, suggesting that foliated metamorphic rocks lead to stronger OPA than do dipping sedimentary strata. The results also suggest that the fluid-saturation of micro-cracks is not a necessary condition for the occurrence of the SAA mechanism in the near-surface depth range. • Structure-related anisotropy is generally stronger than stress-induced anisotropy. • Consolidated rocks and gravels show higher anisotropy than fine-grained sediments. • Foliated metamorphic rocks show stronger OPA than dipping sedimentary strata. • Fluid-saturation is not necessary for SAA occurrence in near-surface depth range. [ABSTRACT FROM AUTHOR]

The Xisha Trough situated in the northwestern South China Sea (SCS), plays a pivotal role in transporting sediments from the Red River into the deep-sea basin of the SCS, and thus is a critical place to examine variations in source-to-sink process of the Red River-derived sediments associated with past climate and oceanography changes. In this study, we analyzed clay minerals, grain size composition, and specific XRF core scanning elements of sediment core XT-1, retrieved from the northern slope of the Xisha Trough, to assess changes in sediment provenance and their primary influencing factors in the studied area over the last ∼30 ka. The results show that clay minerals are primarily composed of illite+chrolite with a mean of 89%, followed by kaolinite with a mean of 9%; smectite occurs as a minor component. The mean grain size and XRF core scanning elements exhibit a three-phase change that corresponds well to variations in sediment source since the last glacial period. Over the last 29.8 ka, sea level fluctuations are the primary factor controlling changes in provenances and their contributions in the northern slope of the Xisha Trough. During the last glacial from 29.8 to 20.2 ka with lower sea levels, both the Red River and Taiwan were the primary contributors of fine-grained sediments in the lower continental slope of the Xisha Trough. However, with marine transgressions from the last deglaciation, Taiwan gradually became the dominant source of fine-grained sediments, followed by the Red River. Additionally, during the Last Glacial Maximum and the early to middle Holocene periods, the strengthened deep-water current (DWC) and East Asian summer monsoon, respectively, exerted strong impacts on the contribution of Taiwanese sediments to the Xisha Trough. The changing pattern of primary provenance in the studied core is roughly in line with those observed in the northern SCS, while differing from those in the southern regions of the western Xisha Trough. This discrepancy is likely caused by varying influences of the DWC on these regions. • Taiwan is the primary provenance for the Xisha Trough over the last ∼30 ka, followed by the Red River. • Sea level controls changes in the provenance of fine-grained sediment on the north slope of the Xisha Trough. • The DWC is responsible for consistent clay mineral records in lower slope regions of the Xisha Trough and the northern SCS. [ABSTRACT FROM AUTHOR]

Background: The pandemic of COVID-19 has disrupted the clinical pathway for patients with suspected upper tract urothelial carcinoma (UTUC). This aims to investigate the optimal management of UTUC during the pandemic by determining 1) Whether a three-month delay of RNU leads to worsened overall survival, 2) Whether radical nephroureterectomy (RNU) can be performed without prior diagnostic ureteroscopy (URS).Methods: Consecutive patients with RNU performed for suspected UTUC in four hospitals in Hong Kong and Taiwan were included. Patients with histologically proven UTUC and with RNU performed within one year were dichotomized into early (≤3 months) and delayed (>3 months) RNU groups. Diagnostic performances of predictive models based on pre-URS factors (gross haematuria, suspicious or malignant urine cytology, and filling defect or contrast-enhancing mass on computed tomography), with or without URS, were analysed using receiver operating characteristics and area under curve (AUC). Overall survival was analysed using Kaplan-Meier method and multivariate Cox regression analysis.Results: Between 2000 and 2019, 665 patients underwent RNU, and 491 of them had prior diagnostic URS. The early RNU group had a better overall survival (P = 0.015). Early RNU was associated with a better overall survival upon multivariate analysis (HR 1.55, 95% CI 1.03-2.33, P = 0.035). Large tumour size, multi-focal tumour, T2 or above disease, and positive nodal status were associated with a poorer overall survival. A combination of any 2 out of the 3 pre-URS factors achieved a positive predictive value of 99.5 to 100%. Presence of all 3 pre-URS factors achieved an AUC of 0.851 with URS, and AUC of 0.809 without URS.Conclusions: A delay of RNU for over 3 months was associated with poorer overall survival and has to be avoided despite the current COVID-19. We can also consider direct RNU based on clinical factors alone. This also avoids URS hospitalization and expedites the clinical pathway of UTUC. [ABSTRACT FROM AUTHOR]