Uplifting mountains are denudated by gravitational deformation, landslides, and glacial or fluvial erosion. We investigated the response of valley slopes to glacial and fluvial erosion along the Kali ...Gandaki (KG) River, one of the largest rivers that flows through the High Himalaya southward from Tibet to India and diagonally cuts the strikes of gneiss and slate foliations. Satellite images with 2.5 m resolution and 5-m Digital Elevation Models (DEMs) were used for the investigation. Within a 20-km reach of the KG River, we found a series of 11 landslides, which vary from a total area of 0.58 to 12 million m2 each. The foliations generally strike NW–SE and dip at 30° to 50° to the NE, so the left bank slopes are anaclinal and the right bank slopes are cataclinal. On the cataclinal slopes, buckling of beds occurs, and gradual deformation proceeds in slate and two-mica gneiss, while in the more competent calc gneiss, buckling deformation develops into a rock avalanche. Such rock avalanches are represented by the largest Dhampu-Chhoya landslide, which once blocked the KG River and drastically changed the river morphology. Anaclinal slopes of two-mica gneiss were toppled and transformed into rock avalanches on three slopes. The KG River has a prominent fluvial knickpoint, which is currently at an elevation of 1800 m, and it has slope breaks on the left bank that are 200–400 m above the riverbed downstream of the knickpoint. Toppling was observed on slopes higher than slope breaks, which suggests that toppling began before the formation of slope breaks by fluvial incision and that the lower slopes did not adapt to the younger fluvial incision. In contrast, slope breaks are scarcely found on the right bank, probably because slow-moving DGSDs, which followed the river incision, erased them.
•The Himalayan mountains respond to erosion based on geological structures.•Buckling and gradual deformation proceed on dip slopes of incompetent rock.•Buckling of competent rock develops into catastrophic failure.•On anaclinal slopes, toppling and catastrophic failure occur.•Upstream migration of a fluvial knickpoint induced a series of mass movements.•Glacial erosion and deglaciation destabilized the feet of dip slopes, inducing buckling deformation.
Rationale Common pollens in the south of Europe and Mediterranean area are olive, grass and parietaria pollen. Because in some areas there are great extensions of peach cultivar, our aim was to study ...if peach pollen was relevant. Conclusions Sensitisation and allergy to peach pollen must be evaluated in areas with a high cultivars. Because most of the patients are also sensitized to other pollens, the clinical relevance of peach tree pollen must be established.
Rationale Although the prevalence of atopy and sensitisation to inhalants and food allergens is increasing over the years, this is related to age and level of allergen exposure. Skin testing by prick ...with a panel of prevalent inhalant and food allergens was made.
Rationale Sensitization to airborne moulds may be a risk factor for severe asthma and fatal exacerbation Methods A prospective, one-year period (April 2016-March 2017), study looking at the patterns ...of sensitization to common allergens in relation to severe asthma exacerbation mong adult asthmatics who are coming in acute exacerbations at Al-Rashed Allergy Centre in Kuwait. Atmospheric pressure correlated significantly with the concentration of Alternaria and Aspergilus Conclusions Although the rate of allergen sensitization is high, moulds play a minor role in asthma exacerbation
Mục tiêu của nghiên cứu này là xác định hiệu quả của hai dòng vi khuẩn hòa tan kali lên sinh trưởng, năng suất cây cải bó xôi (Spinacia oleracea L.) và một số đặc tính lý, hóa và sinh học đất ở điều ...kiện nhà lưới. Hạt cải bó xôi được chủng với dung dịch vi khuẩn có mật số 108 cfu/mL trong 24 giờ và được trồng trong điều kiện giảm 50% phân kali theo khuyến cáo cho cây cải bó xôi và có bổ sung rơm (1 tấn/ha). Kết quả cho thấy chủng vi khuẩn hòa tan kali kích thích tăng sinh trưởng và tăng năng suất cải bó xôi thêm 45,3-80,0%, tăng hàm lượng Kts trong rau và tăng hàm lượng Ktđ trong đất, đồng thời giảm được 50% lượng phân kali vô cơ theo khuyến cáo sau 1 vụ gieo trồng. Như vậy, hai dòng vi khuẩn hòa tan kali Burkholderia vietnamiensis L1.1 và Staphylococcus hominis T7.3 có tiềm năng để phát triển làm phân bón vi sinh giúp tăng sinh trưởng, năng suất cây trồng, giảm phân bón kali hóa học, thực hiện sản xuất nông nghiệp thân thiện và bền vững.
Highest geomorphic activity in the central Nepal Himalayas is mainly driven by monsoonal precipitation. In contrast, the northern flanks of the Nepal Himalaya lay in the relative dry rain shadow of ...the mountain range.
During the monsoon 2018, major floods and geomorphic events occurred in the Kali Gandaki (KG) valley impacting both the monsoon-affected and the dry parts of the catchments. We analyze the events and its triggers based on field observations, multiple satellite image interpretation, climatological analysis using Global Precipitation Measurement and MODIS snow cover data, hydrological analysis and media analysis.
The hydro-meteorological triggers are complex. Exceptional precipitation in April and May 2018 occurred in the entire study area, followed by a rather dry period. Precipitation in August was exceptional in the northern part whereas below average in the South. We argue that dynamics of snow accumulation and delayed melting contributed significantly to flooding and increased geomorphic activity in the southern part in August whereas flooding in the northern part was mainly triggered by rainfalls. We thus define 2018 as an abnormal (pre-)monsoon year with less rainfall than average but being more catastrophic.
Sediment dynamics in the study area are still controlled by the Dhampu rock avalanche dam and the braided river floodplain north of this knickpoint, where sediment pulses delivered from tributaries are rarely connected from the main river. During the monsoon floods 2018 sediment connectivity was given for most tributaries due to the steepness of the catchments.
The study area is subject to major human impact. Mostly in the south, numerous hillslopes have been undercut by road construction, leading to higher geomorphic sensitivity. Severe landslides might thus be triggered in future even by less intense rainfall events.
Magnitude and frequency of such abnormal (pre-)monsoon precipitation are highly relevant for sediment flux and natural hazards studies.
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•The year 2018 was an abnormal (pre-)monsoon year.•Below average precipitation caused yet more disastrous geomorphic events.•Exceptional snow falls in spring and delayed melting were essential drivers.•Magnitude/frequency of such years are relevant for sediment flux/natural hazards.
ABSTRACT
The spatial climatic characteristics of the Himalayas are complex and a challenge for regional climate models (RCMs). There is no doubt that some form of correction before any application of ...RCM simulations is a must. In recent years, simple bias correction techniques have been overshadowed by more popular and complex bias correction techniques. In this study an attempt is made to compare the performance of a simple and of a comparatively complex correction technique for hydrological analysis at a monthly resolution in the Kaligandaki River Basin of Nepal. The research workflow consists of bias correction of temperature and precipitation using a simple technique (linear scaling) and a comparatively complex one (quantile mapping). The performance at monthly resolution is evaluated against observed meteorological data while a combined evaluation is made via hydrological model response analysis. The wetter and colder RCM estimates were significantly improved after bias correction. The hydrological modelling response also shows the importance of the bias correction of the RCMs. However, no significant difference was observed between the outputs of linear scaling and quantile mapping which exhibited almost identical performances. Hence, this study has a novel conclusion that a simple method, such as linear scaling, is sufficient for hydrological analysis at monthly resolution.
Artikel ini mengkaji mengenai bencana banjir yang melanda Madiun pada tahun 1940-1989. Penelitian ini menggunakan metode penelitian sejarah. Dalam artikel ini, diketahui bahwa banjir di Madiun telah ...terjadi secara rutin jauh sebelum masa reformasi. Hal itu disebabkan oleh berbagai faktor, tidak hanya kondisi alam, tetapi juga aktivitas manusia. Salah satu faktor dominan yang menjadi penyebab banjir adalah curah hujan. Selain curah hujan, banjir disebabkan karena adanya anak sungai Bengawan Solo, yakni Kali Madiun. Setiap tahun, terutama ketika musim hujan, Kali Madiun akan mendapat kiriman dari kawasan hulu beserta anak-anak sungainya, sehingga membuat air sungai meluap. Akibat banjir yang rutin terjadi, penduduk Madiun mengalami kerugian, baik material, finansial, maupun korban jiwa. Oleh karena itu, pemerintah berupaya untuk melakukan penanggulangan bencana, di antaranya melalui Proyek Pengembangan Wilayah Sungai Bengawan Solo hingga Madiun River Urgent Flood Control Project (MRUFCP).
Flood in Kali Konto is a disastrous hazard which strikes a lot of housing, infrastructures and paddy fields along its river banks almost every year. In 2021, along with destroyed revertment at ...roolagh 70 area, flood inundated more than 10 villages in Kabupaten Jombang and several more in Malang and Kediri. However, flood management at Kali Konto needs special consideration because several conditions, include watershed area pattern, extremely slope condition changing, numerous materials from Kelud mountain eruption in several part of Konto river, and a lot of infrastructures which laid in Konto river. This paper discussed about appropriate infrastructures which derived from hydrology and hydraulics modeling for Q2 and Q50 flood return periods. Since the model resulted 49 locations, Analytical Hierarchy Process (AHP) model used for determining priority for scaling down flood hazard in Kali Konto. The most priority comes to Karang Tengah, Blaru and Bugasur Kedaleman area based on the most losses occurred.
•High erosion potential zones are concentrated around structural discontinuities.•The region around Main Central Thrust exhibits higher vulnerability to erosion.•About 55% of landslide are located in ...the high -very high erosion potential zones.•The highest landslide density was across the active Seraghat-Tintola Fault (STF).
The Kumaun Himalaya registers frequent seismicity, neotectonic behaviour and incessant rainfall which accelerate hillslope processes governing landsliding phenomenon. Within the Kali Basin between Jauljibi and Garbyang, morphometric analysis of 45 fourth order sub-basins were carried out to prepare an erosion potential map of the region. The spatial distribution of 376 landslides including 158 debris slide and 97 rockfalls correlates well with the erosion map depicting 40% landslides in very high zone, 15% in high zone, 33% in moderate zone, 12% in low zone across the Kali Basin. The dominant parameters responsible for the erosion were evaluated using statistical methods such as Principal Component Analysis (PCA) and Agglomerative Hierarchal clustering (AHC). The comparison of PC1, PC2 and PC3 illustrates high erosion activity around the Main Central Thrust (MCT) and within the Vaikrita and Chipplakote formations which strongly reflect the function of basin dimension, bifurcation ratio, drainage density, relief and shape parameters for sub-basins exhibiting high proneness to flooding and typical surface runoff. The PCA results are consistent with AHC, where AHC clusters correspond with PCA factor loadings. Morphotectonic analysis using steepness index (Ksn) and valley floor width to height ratio (Vf) for the Kali and Dhauli rivers were integrated with landslide inventory that indicate the highest landslide density across the active Seraghat-Tintola Fault (STF) near Tawaghat and moderate to high density near topographic fronts of closely spaced active Lasku Fault (LF), Ghatibagar Kalika Fault (GKF) Rauntis Fault (RF) that outcrop within the Lesser Himalayan Sequences(LHS) exposed between Dharchula and Jauljibi.
The study provides an understanding of quantitative geomorphometry as an useful approach to identify potentially active zones for slope failures and provide a guide to decision-makers in regional planning and mitigating the landslide hazard in the Kali valley which is developing hub for large scale infrastructural and tourist activities.
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