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[Display omitted] • The Budyko framework was applied to 75 catchments covering a large area of Taiwan. • Varied landscape effects determined water resources availability among catchments. • Considerable spatial variability in the Budyko-related variables were found. • Three clusters were identified based on catchments' movements in the Budyko space. • 64 catchments will face the reduced availability of future water resources. Assessing water resources availability in a changing climate is a determinant of promoting sustainable development in a region. Such assessment should better be inter-basin in order to unveil a region's overall risk, so a time-varying Budyko framework is developed and adopted in this study. Gauge-based gridded precipitation and temperature, in company with runoff data, were used to derive the Budyko curves for 75 catchments over Taiwan. Downscaled precipitation and temperature data from selected global climate models and Representative Concentration Pathways (RCPs) were then used to calculate the shifts in the Budyko space of each catchment. It was found that the Budyko-related variables (e.g., evaporative and aridity indices, and catchment-specific parameter) exhibited considerable variability island-wide, with a few outliers in certain catchments being modulated by distinct landscape features and/or human activities. Under all RCPs analyzed, the majority of catchments showed the magnified movement vectors pointing at the 1st quadrant in the Budyko space in the late-21st century, suggesting a predominant and aggravating drying trend over Taiwan. Cluster analysis of the movement vectors under RCP8.5, which entailed the least inter-model differences, identified three major clusters, two of which (64 catchments included) indicated a drying trend of varied significancy. According to our findings, without effective mitigation of climate change, an increased likelihood of the worst-case scenario will substantialize the reduced availability of Taiwan's water resources. [ABSTRACT FROM AUTHOR]

The apportionment of riverine dissolved inorganic nitrogen (DIN) load to individual land use on a watershed scale demands the support of accurate DIN load estimation and differentiation of point and non-point sources, but both of them are rarely quantitatively determined in small montane watersheds. We introduced the Danshui River watershed of Taiwan, a mountainous urbanized watershed, to determine the export coefficients via a reverse Monte Carlo approach from riverine DIN load. The results showed that the dynamics of N fluctuation determines the load estimation method and sampling frequency. On a monthly sampling frequency basis, the average load estimation of the methods (GM, FW, and LI) outperformed that of individual method. Export coefficient analysis showed that the forest DIN yield of 521.5 kg-N km −2 yr −1 was ~ 2.7-fold higher than the global riverine DIN yield (mainly from temperate large rivers with various land use compositions). Such a high yield was attributable to high rainfall and atmospheric N deposition. The export coefficient of agriculture was disproportionately larger than forest suggesting that a small replacement of forest to agriculture could lead to considerable change of DIN load. The analysis of differentiation between point and non-point sources showed that the untreated wastewater (non-point source), accounting for ~ 93% of the total human-associated wastewater, resulted in a high export coefficient of urban. The inclusion of the treated and untreated wastewater completes the N budget of wastewater. The export coefficient approach serves well to assess the riverine DIN load and to improve the understanding of N cascade. [ABSTRACT FROM AUTHOR]

This study is aimed to select optimum keratin degradation ability from Bacillus strains for feather meal-soybean meal fermentation, and favorably water content for the strain during fermentation of feather meal-soybean meal, and finally investigate the effects of the fermented feather meal-soybean meal product (FFSMP) on growth performance, carcass trait, clinical blood biochemistry, and intestinal morphology of broilers. Thirty-six bacteria strains from soil, sewage pool, and feather waste were screened and selected Bacillus subtilis var. natto N21 (N21), B. subtilis CU14 (CU14), and B. amyloliquefaciens CU33 (CU33) with better keratinase activity and feather-degrading rate. The result of trial 1 showed that the FFSMP produced by CU33 had the optimum physiochemical characterizations, amino acid composition and feeding performance for broilers. Hence the effects of water content (45, 50, 55, and 60%) on FFMSP fermentation of CU33 were investigated in trial 2. Result showed that pH value, counts of Bacillus -like bacteria, γ-PGA, viscosity, surfactin yield and odor all significantly increased according to the water content (P < 0.05). The protease activity reached significantly highest in the 55% and 60% water content groups (P < 0.01). The broilers performance of 55% and 60% water content group were significantly higher than control group (P < 0.05) in weight gain (WG), feed intake (b) at 0 to 21-d-old and the WG, feed conversion ratio (FCR), and production efficiency factor at 0 to 35-d-old, and could reach the similar growth performance as fish meal group (P > 0.05). The fermentation groups significantly decreased urea nitrogen (P < 0.05) and increased creatinine (P < 0.05) in the blood. The fermentation groups also significantly decreased the crypt depth in the duodenum (P < 0.05) and increased villus height to crypt depth ratio of the duodenum (P < 0.05). In conclusion, CU33 shows the best degradation rate for feather and keratinase activity, and the FFSMP with a water content of 50% to 60% during fermentation is suggested. Diets supplemented with 5% FFSMP can promote the growth of broilers by improving the morphology of the duodenum and achieve the feeding effect of high-quality fish meal. [ABSTRACT FROM AUTHOR]

This work presents a novel methodology, genetic programming (GP), for developing environmental response functions for Formosan Landlocked Salmon (Oncorhynchus masou formosanus); these functions are then applied to evaluate the impacts of climate changes. Average daily temperature and maximal flows between two sampling periods were adopted as principal factors for categorizing environmental conditions. The GP successfully identified the response functions for various environmental categories. The response functions were further applied to assess the impact of climate change. Fourteen future possible climate scenarios were derived based on the equilibrium and transition experiments by GCMs. Impact assessment results indicated that climate change may significantly influence populations of Formosan Landlocked Salmon due to more frequent higher temperatures. Adaptation strategies are required to mitigate the impact of global climate change as current conservation measures for Formosan Landlocked Salmon habitat only reduce local human-induced effects. In the situation of complicated relationships between fish population and environmental conditions, GP provides a useful tool to obtain some information from the limited data. [Copyright &y& Elsevier]

• A river ceases to flow frequently in humid subtropical regions. • Water and heat fluxes in the streambed were observed and modeled. • Diatom in the fragmented reach might influence the vertical hydraulic conductivity. The endangered Formosan landlocked salmon that habitats only in Chichiwan Creek has been successfully rehabilitated in one of its tributaries, Yusheng Creek. However, the stream fragmentation, no surface streamflow, seriously reduced the salmon population, hampering the restoration work. The surface water-groundwater (SW-GW) interactions in a 500-m reach were examined by installing 6 monitoring wells at 3 sites to record temperatures and groundwater levels at every 15-min for two months. The automatic estimator of VFLUX and numerical model of VS2DH are used to quantify the streambed hydraulic characteristics along the reach. It is found that the entire study reach is a losing stream and the fragmented reaches have significantly higher streambed vertical hydraulic conductivity (VK) compared to the perennial one. The streambed VK at the up-stream perennial reach increased by about double after a rainfall event, probably resulting from the removal of fine grain in the streambed by the rainfall event. Although the fragmented reaches reflowed after the event, streambed VK at the mid- and down-stream fragmented reaches decreased by about 75% and 50%, respectively, compared to the pre-fragmented period. The clogging layers formed by the remains of dead diatom deposited in the streambed during the fragmented period were very likely responsible for the decreased streambed VK. The spatial and temporal variations of streambed VK influenced by hydrological conditions and even bioactivities within such a short distance reveal the complexity of SW-GW interactions. Further studies about the forming processes of clogging layer and its effect on the hydraulic characteristic should be conducted to create a more holistic and reliable picture of interaction processes. [ABSTRACT FROM AUTHOR]

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]

Abstract: Over the past decade, metal-organic frameworks (MOFs) have been extensively studied as a novel approach to store hydrogen. The large surface area and volume of micropores that are intrinsic to MOFs make them ideal for gas adsorption. In addition, we chemically reduced MOF-5 by doping it with alkali metals (Li, Na, and K). We found that the H2 uptake capacity of MOF-5 materials doped with Li, Na, and K exceeded that of a neutral framework by 24%, 68%, and 70%, respectively. Notably, at the same levels of doping, the Li+-doped framework exhibited the strongest H2 binding, and the binding strength decreased sequentially in the order Li+ > Na+ > K+. [Copyright &y& Elsevier]

Abstract: A physics-based stream temperature model [Tung, C.P., Lee, T.Y., Yang, Y.C., 2006. Modelling climate-change impacts on stream temperature of Formosan Landlocked Salmon habitat. Hydrol. Process. 20, 1629–1649] was improved by incorporating shading effects caused by both cliff terrain and riverbank dense vegetation to simulate hourly stream temperature variations in 1 day. Daily maximal stream temperature is a critical factor to the habit distribution of the Formosan Landlocked Salmon, an important and endangered species. Currently, it only can be found in ChiChiaWan Creek and GaoShan Creek in Taiwan. The former stream temperature model only considers the shading effects of cliff terrain and works well for ChiChiaWan Creek, but overestimates stream temperatures of GaoShan Creek having dense riverbank vegetative covers. The model was modified with the Beer''s law and a parameterization scheme to describe the diminishing of the incident solar radiation to take vegetative shading effects into account. Simulation results of GaoShan Creek show the success of this improvement. The shading effects induced by both terrain and vegetation can significantly affect stream temperature distributions. Simulation experiments were conducted to indicate shading effects are varied in different watersheds and seasons. [Copyright &y& Elsevier]

• Silicate cation weathering in Taiwan is 7 fold higher than the global average. • The typhoons account for 1% of a year but transport 10% of silicate cation. • Coupling between weathering and erosion becomes less relevant during typhoons. Temporal variation of the chemical weathering rate (CWR) versus physical erosion rate (PER) and the shift of the sources of dissolved solids during rainstorms are explored in two small mountainous rivers, Northern Taiwan. The ionic hydrochemistry of streamwater, rainwater, soil water, and groundwater were collected to quantitatively demonstrate the sources of the dissolved solids and the coupling effect between CWR and PER during typhoon and non-typhoon periods. Results indicate that silicate cation weathering (CWR SC) varies between 33 and 37 t km−2 yr−1, which is ~7 times the global mean, and the annual PER is ~81–166 t km−2 yr−1, similar to the global mean of ~137 t km−2 yr−1. The rainstorm periods only account for 1% of a year but are responsible for 10% of the CWR SC and over 80% of the sediment flux, highlighting the importance of storm events. Silicate cation concentrations present a simple dilution process during rainstorms indicates the high connectivity between hillslopes and streams during rainstorms is established and forces the soil water into streams rapidly. Besides, the coupling between CWR SC and PER becomes less relevant during rainstorms. The coupling between CWR SC and PER is non-linear with flow regime dynamics, and the estimates of CWR SC derived from non-typhoon day are as largely biased as one order of magnitude. High-resolution water chemistry data on the variations in ion production and physical erosion is more valuable than previously thought for characterizing the CWR and PER of active mountain belts. [ABSTRACT FROM AUTHOR]

A novel ceramic chamber prototype has been designed and fabricated which is described in this paper. The manufacture procedure of the ceramic test chamber is original. For the novel ceramic chamber, the uniformity of its inner deposited Ti film is improved to have a thickness variation of approximately 1%, and the average wall thickness error of the chamber (length 650 mm) is developed to be less than 55 μm. The manufacture procedure is explained below. The two halves of ceramic chambers were first cleaned, the metal films were then deposited on the inner surface by sputtering and, finally, the two halves were joined with a fixture to become a ceramic tube using glass powder colloid at ∼250 °C. The glass powder colloid can be used for the vacuum-assembled parts because the outgassing rate is measured to be 4.8 × 10 −9 Pa m s −1 after baking. For a novel ceramic chamber prototype, the ceramic tube was connected to the stainless steel flange by glass powder colloid and tungsten inert gas (TIG) welding. The ceramic chamber prototype was leak tight after the rapid temperature cycle test. Thus, it is feasible to fabricate the novel ceramic chamber prototype. [ABSTRACT FROM AUTHOR]