river catchment
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Excel spreadsheets containing sample locations and full detrital zircon U-Pb isotopic ratios and age results. Text file containing detailed description of detrital zircon U-Pb results and three supplemental figures.

Excel spreadsheets containing sample locations and full detrital zircon U-Pb isotopic ratios and age results. Text file containing detailed description of detrital zircon U-Pb results and three supplemental figures.

Purpose The purpose of this paper is to prepare flood hazard map and show the extent of flood hazard under climate change scenarios in Woybo River catchment. The hydraulic model, Hydrologic Engineering Center - River Analysis System (HEC-RAS) was used to simulate the floods under future climate scenarios. The impact of climate changes on severity of flooding was evaluated for the mid-term (2041–2070) and long-term (2071–2100) with relative to a baseline period (1971–2000). Design/methodology/approach Future climate scenarios were constructed from the bias corrected outputs of five regional climate models and the inflow hydrographs for 10, 25, 50 and 100 years design floods were derived from the flow which generated from HEC-hydrological modeling system; that was an input for the HEC-RAS model to generate the flood hazard maps in the catchment. Findings The results of this research show that 25.68% of the study area can be classified as very high hazard class while 28.56% of the area is under high hazard. It was also found that 20.20% is under moderate hazard and about 25.56% is under low hazard class in future under high emission scenario. The projected area to be flooded in far future relative to the baseline period is 66.3 ha of land which accounts for 62.82% from the total area. This study suggested that agricultural/crop land located at the right side of the Woybo River near the flood plain would be affected more with the 25, 50 and 100 years design floods. Originality/value Multiple climate models were assessed properly and the ensemble mean was used to prepare flood hazard map using HEC-RAS modeling.

Quantification of soil is crucial for maximizing the advantages of land resources while minimizing the negative consequences of land degradation in the long term. It will also make it possible to identify locations that need immediate soil erosion management. The present study was carried out in the Kulfo river catchment, Rift valley, Southern Ethiopia. The Revised Universal Soil Loss Equation (RUSLE) method was utilized to estimate the mean yearly soil loss in the research region using remote sensing, other collateral data. The RUSLE model inputs were mapped and integrated into the ArcGIS software, and the results show that 0 and 1211 t ha−1year−1 are the minima and maximum soil loss in the present study area. Soil erosion-prone regions were divided into three categories: 0-42 t ha−1year−1 (low), 43-128 t ha−1 year−1 (medium), and > 128 t ha−1 year−1 (high). And the average rate of soil erosion is 68.47 t ha−1year−1. Low, medium, and high soil erosion areal extent and area percentages in the current research area is 270 km2 (77 %), 61 km2 (17 %), and 19 km2 (6%), respectively. A high rate of soil erosion was found where high steep slope, barren land, and high precipitation occurred in the present study area. The current study's outcomes were confirmed by comparing soil loss estimates in the same geo-environmental conditions found in Ethiopia's highlands. The outcome of this study is important for decision-makers and policymakers.

Kutai Lama merupakan salah satu kota lama yang terdapat di daerah aliran Sungai Mahakam. Salah satu bukti hubungan antara Kutai Lama dengan dunia luar adalah banyaknya sebaran pecahan keramik asing, terutama dari Cina, yang padat di sepanjang tepian sungai. Tujuan penelitian ini adalah memahami keberadaan keramik kuno di daerah aliran Sungai Mahakam. Adapun sasaran penelitian ini adalah bentuk dan variasi keramik, sehingga diketahuifungsi serta peranan keramik Cina pada masa itu. Penelitian ini dilakukan karena belum ada penelitian terdahulu yang mengulas tentang besarnya pengaruh eksistensi keramik Cina dalam perkembangan kebudayaan di kawasan Kutai Lama. Situs Kutai Lama merupakan kawasan penting bagi rekonstruksi sejarah awal perkembangan Islam di Kutai Kartanegara. Metode penelitian yang digunakan adalah kualitatif-deskriptif, dan perbandingan-perbandingan berdasarkan literatur keramik Cina. Hasil analisis morfologi dan kronologi menunjukkan bahwa keramik Dinasti Song-Yuan mendominasi populasi temuan keramik di Kutai Lama. Hal ini menjadi indikasi komoditi dagang tersebut dihargai sebagai suatu hadiah, sehingga menjadi barang berharga yang dimiliki oleh kalangan tertentu atau tokoh masyarakat. Kutai Lama is one of the old towns located in the Mahakam River catchment. One of the items of evidence of the relationship between Kutai Lama and the outside world is a large number of fragments of foreign ceramic, especially from China, which was densely found along the banks of the river. The objective of this study was to understand the existence of old ceramics in the Mahakam River catchment. The target of this research was the form and variation of ceramics, thus providing information on the purpose and role of Chinese ceramics then. This research was conducted because there were no previous studies that reviewed the magnitude of the influence of the existence of Chinese ceramics in the cultural development in the Kutai Lama region. The Kutai Lama site is an important area for the reconstruction of the early history of Islamic development in Kutai Kartanegara. The research method used was qualitative-descriptive, and comparative based on Chinese ceramics literature. The results of the morphological and chronological analyses showed that the Song-Yuan Dynasty ceramics dominate the population of ceramic findings in Kutai Lama. This is an indication that such trade commodity was also valued as gifts, therefore, it became valuable items owned by certain groups or community leaders.

Near real-time estimation of soil loss from river catchments is crucial for minimizing environmental degradation of complex river basins. The Chenab river is one of the most complex river basins of the world and is facing severe soil loss due to extreme hydrometeorological conditions, unpredictable hydrologic response, and complex orography. Resultantly, huge soil erosion and sediment yield (SY) not only cause irreversible environmental degradation in the Chenab river catchment but also deteriorate the downstream water resources. In this study, potential soil erosion (PSE) is estimated from the transboundary Chenab river catchment using the Revised Universal Soil Loss Equation (RUSLE), coupled with remote sensing (RS) and geographic information system (GIS). Land Use of the European Space Agency (ESA), Climate Hazards Group InfraRed Precipitation with Station (CHIRPS) data, and world soil map of Food and Agriculture Organization (FAO)/The United Nations Educational, Scientific and Cultural Organization were incorporated into the study. The SY was estimated on monthly, quarterly, seasonal, and annual time-scales using sediment delivery ratio (SDR) estimated through the area, slope, and curve number (CN)-based approaches. The 30-year average PSE from the Chenab river catchment was estimated as 177.8, 61.5, 310.3, 39.5, 26.9, 47.1, and 99.1 tons/ha for annual, rabi, kharif, fall, winter, spring, and summer time scales, respectively. The 30-year average annual SY from the Chenab river catchment was estimated as 4.086, 6.163, and 7.502 million tons based on area, slope, and CN approaches. The time series trends analysis of SY indicated an increase of 0.0895, 0.1387, and 0.1698 million tons per year for area, slope, and CN-based approaches, respectively. It is recommended that the areas, except for slight erosion intensity, should be focused on framing strategies for control and mitigation of soil erosion in the Chenab river catchment.

A breach in embankment of Kosi barrage was reported on 18 August, 2008 which has changed its course and resulted in a fresh channel around 120 km to the east of its previous channel. At the time of failure of the embankment, gushing out of about 2832 m3/s water with great impact breaking into the Mahendra Rajmarg and then taking a southward route into the old 1892-1921 abandoned course of the river, thus leaving the pre-breach C-loop and following a straight route to the Ganga. In this study meteorological aspect are analysed in details in relation to the catastrophic flood in the Kosi river catchment during August 2008. It seems that this catastrophic flood may not be solely due to rainfall in the catchment of Kosi. The breach is due to incorrect strategies of river management, human negligence and poor maintenance of afflux bund of the barrage (Sinha, 2009).