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English as a Medium of Instruction (EMI) is being used to teach academic subjects in international programmes in China to meet the growing number of Chinese students' need to study abroad. Through the lens of inquiry-based science teaching, this study examined how the four EMI science teachers of an international programme at a private high school employed translanguaging in scientific practices such as identifying variables and formulating hypotheses. Based on the data collected from a case study, the analyses demonstrate how these science teachers used multilingual and multimodal resources to facilitate students' engagement in scientific inquiry activities and to promote the construction of scientific knowledge. A total of seven types of translanguaging practices were identified, including opening the inquiry, negotiating directions, teacher encouragement, managing discipline, fun learning environment, definitions, and explanations. The findings imply that pedagogical translanguaging can create a space for the construction of scientific knowledge, as well as a space for the implementation of scientific practices in an inquiry-based EMI classroom environment.

English is being used as a medium of instruction (EMI) for delivering science lessons in China. This study investigated Chinese high school international programme students' perceptions of and attitudes towards EMI, particularly about their perceived difficulties and support in learning. A questionnaire with Likert-type items, student group interviews, and individual teacher interviews were used in the study. Quantitative data were analysed using confirmatory factor analysis and descriptive analysis, while qualitative data were analysed by means of thematic analysis. The findings indicated a mismatch between the difficulties students encountered and the support teachers provided and revealed the problem of passive strategies for teaching science in English. Findings also suggested strategies for supporting students to learn science in the English medium, especially in inquiry-based science classrooms. These findings have important implications for integrating science and English learning.

Effective nitrogen fertilizer management is crucial for reducing nitrous oxide (N2O) emissions while ensuring food security within planetary boundaries. However, climate change might also interact with management practices to alter N2O emission and emission factors (EFs), adding further uncertainties to estimating mitigation potentials. Here, we developed a new hybrid modeling framework that integrates a machine learning model with an ensemble of eight process‐based models to project EFs under different climate and nitrogen policy scenarios. Our findings reveal that EFs are dynamically modulated by environmental changes, including climate, soil properties, and nitrogen management practices. Under low‐ambition nitrogen regulation policies, EF would increase from 1.18%–1.22% in 2010 to 1.27%–1.34% by 2050, representing a relative increase of 4.4%–11.4% and exceeding the IPCC tier‐1 EF of 1%. This trend is particularly pronounced in tropical and subtropical regions with high nitrogen inputs, where EFs could increase by 0.14%–0.35% (relative increase of 11.9%–17%). In contrast, high‐ambition policies have the potential to mitigate the increases in EF caused by climate change, possibly leading to slight decreases in EFs. Furthermore, our results demonstrate that global EFs are expected to continue rising due to warming and regional drying–wetting cycles, even in the absence of changes in nitrogen management practices. This asymmetrical influence of nitrogen fertilizers on EFs, driven by climate change, underscores the urgent need for immediate N2O emission reductions and further assessments of mitigation potentials. This hybrid modeling framework offers a computationally efficient approach to projecting future N2O emissions across various climate, soil, and nitrogen management scenarios, facilitating socio‐economic assessments and policy‐making efforts. [ABSTRACT FROM AUTHOR]

Agricultural activities have been recognized as an important driver of land cover and land use change (LCLUC) and have significantly impacted the ecosystem feedback to climate by altering land surface properties. A reliable historical cropland distribution dataset is crucial for understanding and quantifying the legacy effects of agriculture-related LCLUC. While several LCLUC datasets have the potential to depict cropland patterns in the conterminous US, there remains a dearth of a relatively high-resolution datasets with crop type details over a long period. To address this gap, we reconstructed historical cropland density and crop type maps from 1850 to 2021 at a resolution of 1 km × 1 km by integrating county-level crop-specific inventory datasets, census data, and gridded LCLUC products. Different from other databases, we tracked the planting area dynamics of all crops in the US, excluding idle and fallow farm land and cropland pasture. The results showed that the crop acreages for nine major crops derived from our map products are highly consistent with the county-level inventory data, with a residual less than 0.2×103 ha (0.2 kha) in most counties (>75 %) during the entire study period. Temporally, the US total crop acreage has increased by 118×106 ha (118 Mha) from 1850 to 2021, primarily driven by corn (30 Mha) and soybean (35 Mha). Spatially, the hot spots of cropland distribution shifted from the Eastern US to the Midwest and the Great Plains, and the dominant crop types (corn and soybean) expanded northwestward. Moreover, we found that the US cropping diversity experienced a significant increase from the 1850s to the 1960s, followed by a dramatic decline in the recent 6 decades under intensified agriculture. Generally, this newly developed dataset could facilitate spatial data development, with respect to delineating crop-specific management practices, and enable the quantification of cropland change impacts on the environment. Annual cropland density and crop type maps are available at 10.6084/m9.figshare.22822838.v2 (Ye et al., 2023). [ABSTRACT FROM AUTHOR]

This mixed-method study, employing inquiry-based science teaching theory, delves into the interaction of English Medium Instruction (EMI) and scientific inquiry by investigating science teachers' understanding and perceptions of conducting inquiry-based science activities in EMI classrooms. Drawing on a questionnaire of 166 EMI science teachers and in-depth individual interviews with five of them, the findings suggest that these EMI science teachers encountered similar challenges to other science teachers teaching science in their first languages through an inquiry-based approach. They were found to hold a -scientific -method-oriented understanding of inquiry-based science teaching and a conflict between Chinese learning culture and -inquiry-based science learning culture. Furthermore, the findings indicate that EMI science teachers faced additional challenges in inquiry-based science classrooms in the EMI context, including (a) the tension between passive English learning and the mutual learning of scientific inquiry and English, and (b) the contradictory stance between -inquiry-based science teaching and EMI policy. This study has implications for policymakers in terms of the teaching and provision of -inquiry-based science in the EMI classroom. [ABSTRACT FROM AUTHOR]

Understanding and assessing the spatiotemporal patterns in crop-specific phosphorus (P) fertilizer management is crucial for promoting crop yield and mitigating environmental problems. The existing P fertilizer dataset, derived from sales data, depicts an average application rate on total cropland at the county level but overlooks cross-crop variations. Conversely, the survey-based dataset offers crop-specific application details at the state level yet lacks inter-state variability. By reconciling these two datasets, we developed long-term gridded maps to characterize crop-specific P fertilizer application rates, timing, and methods across the contiguous US at a resolution of 4 km × 4 km from 1850 to 2022. We found that P fertilizer application rate on fertilized area in the US increased from 0.9 g P m-2 yr-1 in 1940 to 1.9 g P m-2 yr-1 in 2022, with substantial variations among crops. However, approximately 40 % of cropland nationwide has remained unfertilized in the recent decade. The hotspots for P fertilizer use have shifted from the southeastern and eastern US to the Midwest and the Great Plains over the past century, reflecting changes in cropland area, crop choices, and P fertilizer use across different crops. Pre-planting (fall and spring) and broadcast application are prevalent among corn, soybean, and cotton in the Midwest and the Southeast, indicating a high P loss risk in these regions. In contrast, wheat and barley in the Great Plains receive the most intensive P fertilizer at planting and via non-broadcast application. The P fertilizer management dataset developed in this study can advance our comprehension in agricultural P budget and facilitate the refinement in P fertilizer best management practices to optimize crop yield and reduce P loss. Datasets are available at https://doi.org/10.5281/zenodo.10700822 (Cao et al., 2024). [ABSTRACT FROM AUTHOR]

Agricultural soils play a dual role in regulating the Earth's climate by releasing or sequestering carbon dioxide (CO2) in soil organic carbon (SOC) and emitting non‐CO2 greenhouse gases (GHGs) such as nitrous oxide (N2O) and methane (CH4). To understand how agricultural soils can play a role in climate solutions requires a comprehensive assessment of net soil GHG balance (i.e., sum of SOC‐sequestered CO2 and non‐CO2 GHG emissions) and the underlying controls. Herein, we used a model‐data integration approach to understand and quantify how natural and anthropogenic factors have affected the magnitude and spatiotemporal variations of the net soil GHG balance in U.S. croplands during 1960–2018. Specifically, we used the dynamic land ecosystem model for regional simulations and used field observations of SOC sequestration rates and N2O and CH4 emissions to calibrate, validate, and corroborate model simulations. Results show that U.S. agricultural soils sequestered 13.2±1.16$$ 13.2\pm 1.16 $$ Tg CO2‐C year−1 in SOC (at a depth of 3.5 m) during 1960–2018 and emitted 0.39±0.02$$ 0.39\pm 0.02 $$ Tg N2O‐N year−1 and 0.21±0.01$$ 0.21\pm 0.01 $$ Tg CH4‐C year−1, respectively. Based on the GWP100 metric (global warming potential on a 100‐year time horizon), the estimated national net GHG emission rate from agricultural soils was 122.3±11.46$$ 122.3\pm 11.46 $$ Tg CO2‐eq year−1, with the largest contribution from N2O emissions. The sequestered SOC offset ~28% of the climate‐warming effects resulting from non‐CO2 GHG emissions, and this offsetting effect increased over time. Increased nitrogen fertilizer use was the dominant factor contributing to the increase in net GHG emissions during 1960–2018, explaining ~47% of total changes. In contrast, reduced cropland area, the adoption of agricultural conservation practices (e.g., reduced tillage), and rising atmospheric CO2 levels attenuated net GHG emissions from U.S. croplands. Improving management practices to mitigate N2O emissions represents the biggest opportunity for achieving net‐zero emissions in U.S. croplands. Our study highlights the importance of concurrently quantifying SOC‐sequestered CO2 and non‐CO2 GHG emissions for developing effective agricultural climate change mitigation measures. [ABSTRACT FROM AUTHOR]

Human‐induced nitrogen–phosphorus (N, P) imbalance in terrestrial ecosystems can lead to disproportionate N and P loading to aquatic ecosystems, subsequently shifting the elemental ratio in estuaries and coastal oceans and impacting both the structure and functioning of aquatic ecosystems. The N:P ratio of nutrient loading to the Gulf of Mexico from the Mississippi River Basin increased before the late 1980s driven by the enhanced usage of N fertilizer over P fertilizer, whereafter the N:P loading ratio started to decrease although the N:P ratio of fertilizer application did not exhibit a similar trend. Here, we hypothesize that different release rates of soil legacy nutrients might contribute to the decreasing N:P loading ratio. Our study used a data‐model integration framework to evaluate N and P dynamics and the potential for long‐term accumulation or release of internal soil nutrient legacy stores to alter the ratio of N and P transported down the rivers. We show that the longer residence time of P in terrestrial ecosystems results in a much slower release of P to coastal oceans than N. If contemporary nutrient sources were reduced or suspended, P loading sustained by soil legacy P would decrease much slower than that of N, causing a decrease in the N and P loading ratio. The longer residence time of P in terrestrial ecosystems and the increasingly important role of soil legacy nutrients as a loading source may explain the decreasing N:P loading ratio in the Mississippi River Basin. Our study underscores a promising prospect for N loading control and the urgency to integrate soil P legacy into sustainable nutrient management strategies for aquatic ecosystem health and water security. [ABSTRACT FROM AUTHOR]

English is being used as a medium of instruction (EMI) for delivering science lessons in China. This study investigated Chinese high school international programme students' perceptions of and attitudes towards EMI, particularly about their perceived difficulties and support in learning. A questionnaire with Likert-type items, student group interviews, and individual teacher interviews were used in the study. Quantitative data were analysed using confirmatory factor analysis and descriptive analysis, while qualitative data were analysed by means of thematic analysis. The findings indicated a mismatch between the difficulties students encountered and the support teachers provided and revealed the problem of passive strategies for teaching science in English. Findings also suggested strategies for supporting students to learn science in the English medium, especially in inquiry-based science classrooms. These findings have important implications for integrating science and English learning. [ABSTRACT FROM AUTHOR]

Perovskite solar cells are attracting more and more attention due to their higher absorption and low cost. However, fabricating the perovskite film with high crystallinity and ideal morphology, which presents large-size and uniform particles with fewer grain boundaries, still needs further improvement. Herein, we introduce MAPbCl3 crystals into the PbI2 film in the sequential deposition process, which obtained the controlled crystallization in perovskite films. The perovskite films induced by MAPbCl3 have stronger crystallinity, fewer defect states, and larger grain size, reducing carrier recombination and improving carrier transfer. The optimized perovskite solar cell (PSC) has achieved a power conversion efficiency of 20.97%. Furthermore, the stability of PSCs has also been enhanced due to the reduced grain boundaries impeding moisture diffusion. This strategy can be applied in other solution-based fabrication processes to improve the photovoltaic performance of PSCs. [ABSTRACT FROM AUTHOR]

Confidence in model estimates of soil CO2 flux depends on assumptions regarding fundamental mechanisms that control the decomposition of litter and soil organic carbon (SOC). Multiple hypotheses have been proposed to explain the role of lignin, an abundant and complex biopolymer that may limit decomposition. We tested competing mechanisms using data‐model fusion with modified versions of the CN‐SIM model and a 571‐day laboratory incubation dataset where decomposition of litter, lignin, and SOC was measured across 80 soil samples from the National Ecological Observatory Network. We found that lignin decomposition consistently decreased over time in 65 samples, whereas in the other 15 samples, lignin decomposition subsequently increased. These "lagged‐peak" samples can be predicted by low soil pH, high extractable Mn, and fungal community composition as measured by ITS PC2 (the second principal component of an ordination of fungal ITS amplicon sequences). The highest‐performing model incorporated soil biogeochemical factors and daily dynamics of substrate availability (labile bulk litter:lignin) that jointly represented two hypotheses (C substrate limitation and co‐metabolism) previously thought to influence lignin decomposition. In contrast, models representing either hypothesis alone were biased and underestimated cumulative decomposition. Our findings reconcile competing hypotheses of lignin decomposition and suggest the need to precisely represent the role of lignin and consider soil metal and fungal characteristics to accurately estimate decomposition in Earth‐system models. [ABSTRACT FROM AUTHOR]

English as a Medium of Instruction (EMI) is being used to teach academic subjects in international programmes in China to meet the growing number of Chinese students' need to study abroad. Through the lens of inquiry-based science teaching, this study examined how the four EMI science teachers of an international programme at a private high school employed translanguaging in scientific practices such as identifying variables and formulating hypotheses. Based on the data collected from a case study, the analyses demonstrate how these science teachers used multilingual and multimodal resources to facilitate students' engagement in scientific inquiry activities and to promote the construction of scientific knowledge. A total of seven types of translanguaging practices were identified, including opening the inquiry, negotiating directions, teacher encouragement, managing discipline, fun learning environment, definitions, and explanations. The findings imply that pedagogical translanguaging can create a space for the construction of scientific knowledge, as well as a space for the implementation of scientific practices in an inquiry-based EMI classroom environment. [ABSTRACT FROM AUTHOR]

The terrestrial biosphere can release or absorb the greenhouse gases, carbon dioxide (C[O.sub.2]), methane (C[H.sub.4]) and nitrous oxide ([N.sub.2]O), and therefore has an important role in regulating atmospheric composition and [...]

The land of the conterminous United States (CONUS) has been transformed dramatically by humans over the last four centuries through land clearing, agricultural expansion and intensification, and urban sprawl. High-resolution geospatial data on long-term historical changes in land use and land cover (LULC) across the CONUS are essential for predictive understanding of natural–human interactions and land-based climate solutions for the United States. A few efforts have reconstructed historical changes in cropland and urban extent in the United States since the mid-19th century. However, the long-term trajectories of multiple LULC types with high spatial and temporal resolutions since the colonial era (early 17th century) in the United States are not available yet. By integrating multi-source data, such as high-resolution remote sensing image-based LULC data, model-based LULC products, and historical census data, we reconstructed the history of land use and land cover for the conterminous United States (HISLAND-US) at an annual timescale and 1 km × 1 km spatial resolution in the past 390 years (1630–2020). The results show widespread expansion of cropland and urban land associated with rapid loss of natural vegetation. Croplands are mainly converted from forest, shrub, and grassland, especially in the Great Plains and North Central regions. Forest planting and regeneration accelerated the forest recovery in the Northeast and Southeast since the 1920s. The geospatial and long-term historical LULC data from this study provide critical information for assessing the LULC impacts on regional climate, hydrology, and biogeochemical cycles as well as achieving sustainable use of land in the nation. The datasets are available at 10.5281/zenodo.7055086 (Li et al., 2022). [ABSTRACT FROM AUTHOR]