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Pour mieux comprendre l'application mondiale des modèles de prédiction de l'érosion des sols, nous avons examiné de manière approfondie la littérature de recherche pertinente évaluée par des pairs sur la modélisation de l'érosion des sols publiée entre 1994 et 2017. Nous avons cherché à identifier (i) les processus et les modèles les plus fréquemment abordés dans la littérature, (ii) les régions dans lesquelles les modèles sont principalement appliqués, (iii) les régions qui restent non traitées et pourquoi, et (iv) la fréquence des études menées pour valider/évaluer les résultats des modèles par rapport aux données mesurées. Pour mener à bien cette tâche, nous avons combiné les connaissances collectives de 67 scientifiques spécialistes de l'érosion des sols de 25 pays. La base de données résultante, intitulée « Global Applications of Soil Erosion Modelling Tracker (GASEMT) », comprend 3030 enregistrements de modélisation individuels provenant de 126 pays, englobant tous les continents (à l'exception de l'Antarctique). Sur les 8471 articles identifiés comme potentiellement pertinents, nous avons examiné 1697 articles appropriés et systématiquement évalué et transféré 42 attributs pertinents dans la base de données. Cette base de données GASEMT fournit des informations complètes sur l'état de l'art des modèles d'érosion des sols et des applications de modèles dans le monde entier. Cette base de données vise à soutenir la prochaine évaluation mondiale de l'érosion des sols par les Nations Unies basée sur les pays, en plus d'aider à éclairer les priorités de recherche sur l'érosion des sols en construisant une base pour de futures analyses ciblées et approfondies. GASEMT est une base de données open-source à la disposition de l'ensemble de la communauté des utilisateurs pour développer la recherche, corriger les erreurs et faire des extensions futures. Para comprender mejor la aplicación global de los modelos de predicción de la erosión del suelo, revisamos exhaustivamente la literatura de investigación relevante revisada por pares sobre modelos de erosión del suelo publicada entre 1994 y 2017. Nuestro objetivo fue identificar (i) los procesos y modelos abordados con mayor frecuencia en la literatura, (ii) las regiones dentro de las cuales se aplican principalmente los modelos, (iii) las regiones que permanecen sin abordar y por qué, y (iv) con qué frecuencia se realizan estudios para validar/evaluar los resultados del modelo en relación con los datos medidos. Para realizar esta tarea, combinamos el conocimiento colectivo de 67 científicos de erosión de suelos de 25 países. La base de datos resultante, denominada 'Global Applications of Soil Erosion Modelling Tracker (GASEMT)', incluye 3030 registros de modelado individuales de 126 países, que abarcan todos los continentes (excepto la Antártida). De los 8471 artículos identificados como potencialmente relevantes, revisamos 1697 artículos apropiados y evaluamos y transferimos sistemáticamente 42 atributos relevantes a la base de datos. Esta base de datos GASEMT proporciona información integral sobre el estado del arte de los modelos de erosión del suelo y las aplicaciones de modelos en todo el mundo. Esta base de datos tiene la intención de apoyar la próxima evaluación mundial de la erosión del suelo de las Naciones Unidas basada en los países, además de ayudar a informar las prioridades de investigación de la erosión del suelo mediante la creación de una base para futuros análisis específicos y en profundidad. GASEMT es una base de datos de código abierto disponible para toda la comunidad de usuarios para desarrollar investigaciones, rectificar errores y realizar futuras expansiones. To gain a better understanding of the global application of soil erosion prediction models, we comprehensively reviewed relevant peer-reviewed research literature on soil-erosion modelling published between 1994 and 2017. We aimed to identify (i) the processes and models most frequently addressed in the literature, (ii) the regions within which models are primarily applied, (iii) the regions which remain unaddressed and why, and (iv) how frequently studies are conducted to validate/evaluate model outcomes relative to measured data. To perform this task, we combined the collective knowledge of 67 soil-erosion scientists from 25 countries. The resulting database, named 'Global Applications of Soil Erosion Modelling Tracker (GASEMT)', includes 3030 individual modelling records from 126 countries, encompassing all continents (except Antarctica). Out of the 8471 articles identified as potentially relevant, we reviewed 1697 appropriate articles and systematically evaluated and transferred 42 relevant attributes into the database. This GASEMT database provides comprehensive insights into the state-of-the-art of soil- erosion models and model applications worldwide. This database intends to support the upcoming country-based United Nations global soil-erosion assessment in addition to helping to inform soil erosion research priorities by building a foundation for future targeted, in-depth analyses. GASEMT is an open-source database available to the entire user-community to develop research, rectify errors, and make future expansions. للحصول على فهم أفضل للتطبيق العالمي لنماذج التنبؤ بتآكل التربة، قمنا بمراجعة شاملة للأدبيات البحثية ذات الصلة التي استعرضها الأقران حول نمذجة تآكل التربة المنشورة بين عامي 1994 و 2017. كنا نهدف إلى تحديد (1) العمليات والنماذج التي يتم تناولها بشكل متكرر في الأدبيات، (2) المناطق التي يتم فيها تطبيق النماذج في المقام الأول، (3) المناطق التي لا تزال دون معالجة ولماذا، و (4) عدد المرات التي يتم فيها إجراء دراسات للتحقق من صحة/تقييم نتائج النموذج بالنسبة للبيانات المقاسة. لأداء هذه المهمة، جمعنا المعرفة الجماعية لـ 67 عالمًا في مجال تآكل التربة من 25 دولة. تتضمن قاعدة البيانات الناتجة، المسماة "التطبيقات العالمية لتتبع نمذجة تآكل التربة (GASEMT )"، 3030 سجل نمذجة فردي من 126 دولة، تشمل جميع القارات (باستثناء القارة القطبية الجنوبية). من بين 8471 مقالة تم تحديدها على أنها ذات صلة محتملة، قمنا بمراجعة 1697 مقالة مناسبة وقمنا بتقييم ونقل 42 سمة ذات صلة بشكل منهجي إلى قاعدة البيانات. توفر قاعدة بيانات GASEMT هذه رؤى شاملة حول أحدث نماذج تآكل التربة وتطبيقات النماذج في جميع أنحاء العالم. تهدف قاعدة البيانات هذه إلى دعم التقييم العالمي المقبل لتآكل التربة الذي تجريه الأمم المتحدة على المستوى القطري بالإضافة إلى المساعدة في توجيه أولويات أبحاث تآكل التربة من خلال بناء أساس للتحليلات المتعمقة المستهدفة في المستقبل. GASEMT هي قاعدة بيانات مفتوحة المصدر متاحة لمجتمع المستخدمين بأكمله لتطوير البحث وتصحيح الأخطاء وإجراء التوسعات المستقبلية.

Soil erosion is one of the global threats to the environment. Further, climate and vegetation changes have pronounced effects on soil erosion in high-mountain areas. In this study, the revised universal soil loss equation (RUSLE) was improved by developing a method for calculating snowmelt runoff erosivity based on a simulated snowmelt runoff and the observed sediment load, using which the soil erosion rate in the upper Heihe River Basin (UHRB) was calculated. The proposed approach provides an effective method for estimating the soil erosion rate and identifying the causes for its change in high-mountain areas. The normalized difference vegetation index (NDVI) was significantly and positively correlated with both precipitation and temperature in the region and exhibited a significant increasing trend. The increase in NDVI led to a decrease in the soil erosion rate (for the annual, rainfall, and snowmelt periods), although erosive rainfall and snowmelt runoff showed increasing trends, indicating the dominating impact of vegetation cover on soil erosion. The average soil erosion rate of UHRB was 806.2 t km−2 a−1 from 1982 to 2015. On average, soil erosion during rainfall and snowmelt periods contributed to 90.67% and 9.33% of annual soil erosion, respectively. However, the resultant soil erosion rate caused by 1 mm of snowmelt runoff was about 1.9 times that caused by 1 mm erosive rainfall. Soil erosion during the snowmelt period was particularly sensitive to temperature and showed consistent responses to climate and vegetation changes in UHRB and its two tributaries. An increasing NDVI promoted by climate change and anthropogenic factors played a major role in alleviating soil erosion, and the warming exerted intense impacts on soil erosion during the snowmelt period. These findings would be helpful for proposing effective measures for soil conservation in high-mountain areas under climate and vegetation changes.

The Poyang Lake Basin has been suffering from severe water problems such as floods and droughts. This has led to great adverse impacts on local ecosystems and water resource utilization. It is therefore important to understand stream flow changes and their driving factors. In this paper, the dynamics of stream flow and precipitation in the Poyang Lake Basin between 1961 and 2012 were evaluated with the Mann–Kendall test, Theil–Sen approaches, Pettitt test, and Pearson’s correlation. Stream flow was measured at the outlets of five major tributaries of Poyang Lake, while precipitation was recorded by fourteen meteorological stations located within the Poyang Lake Basin. Results showed that annual stream flow of all tributaries and the precipitation over the study area had insignificant (P > 0.1) temporal trends and change points, while significant trends and shifts were found in monthly scale. Stream flow concentration indices (SCI) at Waizhou, Meigang, and Wanjiabu stations showed significant (P < 0.05) decreasing trends with change points emerging in 1984 at Waizhou and 1978 at Wanjiabu, while there was no significant temporal trend and change point detected for the precipitation concentration indices (PCI). Correlation analysis indicated that area-average stream flow was closely related to area-average precipitation, but area-average SCI was insignificantly correlated with area-average PCI after change point (1984). El Niño/Southern Oscillation (ENSO) had greater impacts on stream flow than other climate indices, and La Niña events played a more important role in stream flow changes than EI Niño. Human activities, particularly in terms of reservoir constructions, largely altered the intra-annual distribution of stream flow but its effects on the amount of stream flow were relatively low. Results of this study provided a useful reference to regional water resource management and the prevention of flood and drought disasters.

The sediment load on the Chinese Loess Plateau has sharply decreased in recent years. However, the contribution of terrace construction and vegetation restoration projects to sediment discharge reduction remains uncertain. In this paper, eight catchments located in the Loess Plateau were chosen to explore the effects of different driving factors on sediment discharge changes during the period from the 1960s to 2012. Attribution approaches were applied to evaluate the effects of climate, terrace, and vegetation coverage changes on sediment discharge. The results showed that the annual sediment discharge decreased significantly in all catchments ranging from -0.007 to -0.039 Gt·yr-1. Sediment discharge in most tributaries has shown abrupt changes since 1996, and the total sediment discharge was reduced by 60.1% during 1997-2012. We determined that increasing vegetation coverage was the primary factor driving the reductions in sediment loads since 1996 and accounted for 47.7% of the total reduction. Climate variability and terrace construction accounted for 9.1% and 18.6% of sediment discharge reductions, respectively.

The loessial tableland is a unique landform type on the Loess Plateau in China. Long-term soil erosion has led to the retreat of gullies and the rapid reduction of fertile arable land, which has further decreased agricultural production. In this study, we chose the Malian River basin to analyze the temporal and spatial variation of its runoff and sediment load, as well as the potential causes. The annual runoff and sediment load at six hydrological stations in the study area were collected for the period between 1960 and 2016. The Mann−Kendall and Pettitt tests were respectively applied to detect temporal variations and abrupt changes in the runoff and sediment loads. The results showed that an abrupt change in the runoff and sediment loads occurred in 2003. The average annual runoff in the Malian River was 4.42 × 108 m3 yr−1 from 1960 to 2002, and decreased to 3.32 × 108 m3 yr−1 in 2003–2016. The average annual sediment load was 1.27 × 108 t yr−1 in 1960–2002, and decreased to 0.65 × 108 t yr−1 in 2003–2016. The spatial patterns in the sediment load suggested that the Hongde sub-basin contributed a higher sediment count to the Malian River, which may require additional attention for soil and water conservation in the future. Anthropogenic activities significantly affected runoff and sediment load reduction according to the double-mass curve method, accounting for 90.7% and 78.7%, respectively, whereas rainfall changes were 9.3% and 21.3%, respectively. As such, the present study analyzed the loessial tableland runoff and sediment load characteristics of the Malian River basin for soil and water erosion management.

Soil water and nutrients are major factors limiting crop productivity. In the present study, soil water use efficiency (WUE) and crop yield of millet and soybean were investigated under nine fertilization regimes (no nitrogen (N) and no phosphorus (P) (CK), 120 kg ha−1 N and no P (N1P0), 240 kg ha−1 N and no P (N2P0), 45 kg ha−1 P and no N (N0P1), 90 kg ha−1 P and no N (N0P2), 120 kg ha−1 N and 45 kg ha−1 P (N1P1), 240 kg ha−1 N and 45 kg ha−1 P (N2P1), 120 kg ha−1 N and 90 kg ha−1 P (N1P2), 240 kg ha−1 N and 90 kg ha−1 P (N2P2)) in the Loess Plateau, China. We conducted fertilization experiments in two cultivation seasons and collected soil nutrient, water use, and crop yield data. Combined N and P fertilization resulted in the greatest increase in crop yield and WUE, followed by the single P fertilizer application, and single N fertilizer application. The control treatment, which consisted of neither P nor N fertilizer application, had the least effect on crop yield. The combined N and P fertilization increased soil organic matter (SOM) and soil total N, while soil water consumption increased in all treatments. SOM and total N content increased significantly when compared to the control conditions, by 27.1–81.3%, and 301.3–669.2%, respectively, only under combined N and P application. The combined N and P application promoted the formation of a favorable soil aggregate structure and improved soil microbial activity, which accelerated fertilizer use, and enhanced the capacity of soil to maintain fertilizer supply. Crop yield increased significantly in all treatments when compared to the control conditions, with soybean and millet yields increasing by 82.5–560.1% and 55–490.8%, respectively. The combined application of N and P fertilizers increased soil water consumption, improved soil WUE, and satisfied crop growth and development requirements. In addition, soil WUE was significantly positively correlated with crop yield. Our results provide a scientific basis for rational crop fertilization in semi-arid areas on the Loess Plateau.