Natural and human-induced landslides in a tropical mountainous region: the Rift flank west of Lake Kivu (DR Congo)

Abstract. Tropical mountainous regions are often identified as landslide hotspots with particularly vulnerable populations. Anthropogenic factors are assumed to play a role in the occurrence of landslides in these populated regions, yet the relative importance of these human-induced factors remains poorly documented. In this work, we aim to explore the impact of forest cover dynamics, roads and mining activities on the occurrence of landslides in the Rift flank west of Lake Kivu in the DR Congo. To do so, we compile an inventory of 2730 landslides using © Google Earth imagery, high resolution topographic data, historical aerial photographs from the 1950’s and extensive field surveys. We identify old and recent (post 1950’s) landslides, making a distinction between deep-seated and shallow landslides, road landslides and mining landslides. We find that susceptibility patterns and area distributions are different between old and recent deep-seated landslides, which shows that natural factors contributing to their occurrence were either different or changed over time. Observed shallow landslides are recent processes that all occurred in the past two decades. The analysis of their susceptibility indicates that forest dynamics and the presence of roads play a key role in their regional distribution pattern. Under similar topographic conditions, shallow landslides are more frequent, but of smaller size, in areas where deforestation has occurred since the 1950’s as compared to shallow landslides in forest areas, i.e. in natural environments. We attribute this size reduction to the decrease of regolith cohesion due to forest loss, which allows for a smaller minimum critical area for landsliding. In areas that were already deforested in 1950’s, shallow landslides are less frequent, larger, and occur on less steep slopes. This suggests a combined role between regolith availability and soil management practices that influence erosion and water infiltration. Mining activities increase the odds of landsliding. Mining and road landslides are larger than shallow landslides but smaller than the recent deep-seated instabilities. The susceptibility models calibrated for shallow and deep-seated landslides do not predict them well, highlighting that they are controlled by environmental factors that are not present under natural conditions. Our analysis demonstrates the role of human activities on the occurrence of landslides in the Lake Kivu region. Overall, it highlights the need to consider this context when studying hillslope instability characteristics and distribution patterns in regions under anthropogenic pressure. Our work also highlights the importance of considering the timing of landslides over a multi-decadal period of observation.

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Characteristics, distribution and susceptibility of natural and human-induced landslides in a tropical mountainous region: the Rift flank west of Lake Kivu (DR Congo)

10.5194/egusphere-egu21-13380 ◽

2021 ◽

Author(s):

Jean-Claude Maki Mateso ◽

Charles Bielders ◽

Elise Monsieurs ◽

Arthur Depicker ◽

Benoît Smets ◽

...

Keyword(s):

Management Practices ◽

Google Earth ◽

Shallow Landslides ◽

Water Infiltration ◽

Aerial Photographs ◽

Anthropogenic Factors ◽

Natural Environments ◽

Dr Congo ◽

Mountainous Regions ◽

Lake Kivu

Tropical mountainous regions are often identified as landslide hotspots with particularly vulnerable populations. Whereas both natural (e.g., rainfall, lithology) and anthropogenic (e.g., deforestation, mining) factors are expected to be involved in landslide occurrence, the relative importance of such factors remains poorly documented. The objective of this study is to understand the role played by natural and anthropogenic factors in the occurrence of landslides in the Rift Flank west of Lake Kivu in DR Congo. First, we inventoried 2856 landslides of various types using Google Earth imagery, high resolution topographic data, historical aerial photographs from1950&#8217;sand intense field surveys. We made a distinction between old and recent deep-seated landslides, shallow landslides and mining-related landslides. The difference in susceptibility patterns and in size distributions between old and recent deep-seated landslides indicates that natural factors contributing to their occurrence were either different or changed over time. The shallow landslides are all recent. The susceptibility analysis shows that their regional pattern is mainly controlled by forest dynamics and the presence of roads. The occurrence of shallow landslides in forest areas, i.e. in natural environments, strongly increases with slope gradient. In areas with similar topographic conditions where deforestation has occurred since the 1950&#8217;s, shallow landslides are more frequent, but of smaller size. This size reduction is attributed to the decrease of regolith cohesion due to forest loss, which allows a smaller minimum critical area for landsliding. In areas that were already deforested in 1950&#8217;s, shallow landslides are less frequent, larger, and occur on less steep slopes. This suggests a combined role between regolith availability and soil management practices that influence erosion and water infiltration. Landslides associated with mining activities are larger than shallow landslides but smaller than the recent deep-seated instabilities. They are not well predicted by the susceptibility models, showing that they respond to environmental factors that are not present under natural conditions. This research highlights the importance of human activities on the occurrence of landslides and the need to consider this context when studying hillslope instability patterns in regions under anthropic pressure.&#160;Keywords: landslide processes, multi-temporal inventory, historical deforestation, mining and quarrying, susceptibility assessment, Africa

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Drivers of Timberline Dynamics in Rodna Montains, Northern Carpathians, Romania, over the Last 131 Years

Sustainability ◽

10.3390/su13042089 ◽

2021 ◽

Vol 13 (4) ◽

pp. 2089

Author(s):

Dumitru Mihăilă ◽

Petruț-Ionel Bistricean ◽

Vasilică-Dănuț Horodnic

Keyword(s):

Anthropogenic Activities ◽

Land Use Changes ◽

Aerial Photographs ◽

Anthropogenic Factors ◽

Anthropogenic Pressure ◽

Northern Slope ◽

Southern Slope ◽

Eastern Carpathians ◽

Upper Timberline ◽

The Impact

Currently, there is little information regarding the recent spatiotemporal dynamics of upper timberline in the Carpathian Mountains. We reconstructed the temporal (1887–2018) and spatial dynamics of upper timberline in the Rodna Mountains (Eastern Carpathians) based on seven sets of maps and aerial photographs and explained its variability in relation to three main drivers: air temperature, land morphometry and anthropogenic pressure. The impact of natural drivers (temperature, morphometry) on timberline position was evaluated using a high-resolution digital elevation model, local and regional instrumental and modelled climate databases. The impact of anthropogenic factors on timberline position was documented from published sources such as local paleolimnological studies and historical documents. Results show that timberline rose on average with 113 ± 2 m on the northern slope of the Rodna Mts (currently reaching 1640 m above sea level (a.s.l.)) and with 182 ± 2 m on the southern slope (up to an elevation of 1539 m a.s.l.). Our results suggest that this pattern might be connected with the rising temperature over the recent decades. On the northern slope where land morphometry restricts anthropogenic activities, timberline reached the highest elevation. On the more accessible southern slope, anthropogenic land-use changes likely moderated timberline elevational rise under increasing temperatures.

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Morphological variability of Bembidion aspericolle (Coleoptera, Carabidae) populations in conditions of anthropogenic impact

Biosystems Diversity ◽

10.15421/011903 ◽

2019 ◽

Vol 27 (1) ◽

pp. 21-25

Author(s):

V. O. Komlyk ◽

V. V. Brygadyrenko

Keyword(s):

Body Length ◽

Anthropogenic Impact ◽

Morphological Variability ◽

The Body ◽

Anthropogenic Factors ◽

Head Width ◽

Anthropogenic Pressure ◽

Angular Characteristic ◽

Western Palearctic ◽

The Impact

Bembidion (Talanes) aspericolle (Germar, 1829) is a Western Palearctic species which lives on the shores of the Atlantic Ocean, the Mediterranean, Black and Caspian Seas and saline inland habitats from Central Europe to Central Asia. Anthropogenic impact is one of the most important environmental factors affecting the morphological variability of ground beetles. The objective of our research is assessment of the morphological variability of this species in three ecosystems differing by intensity of anthropogenic impact. 13 linear characteristics, one angular characteristic, density of pores on the prothorax and elytra, contrast of spots on the beetles’ elytra were measured, and 6 morphometric indices were calculated. The mean value of body length in females is more than in males in the studied populations. In the ecosystem with high anthropogenic pressure, female body length is shorter by 3.7% and elytra length is shorter by 6.0% than in females in the ecosystem with low anthropogenic impact. Differences between populations in the body length of males are not significant. In the ecosystem with high anthropogenic transformation, sexual dimorphism is observed only on head and prothorax width. The ratio of maximum width of elytra to maximum prothorax width decreases significantly with increasing anthropogenic load. The impact of anthropogenic factors on the ecosystem produces significant changes in elytra length and head width of B. aspericolle and in four of the six morphometric indices. It is reasonable to use these morphometric characteristics of B. aspericolle adults in bioindication. The complex of anthropogenic factors does not have a significant impact on the value of anterior and posterior angles of prothorax, density of prothorax and elytra puncturing and contrast of the light spots at the top of the elytra. The sex of the specimen influences all linear characteristics. The absence of significant differences in morphometric indices between males and females shows that the body proportions of the beetles remain unchanged and only linear dimensions vary. Research on the morphological variability of B. aspericolle is important for understanding microevolutionary processes in populations of beetles under anthropogenically induced changes in the environment.

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METHODS OF COMPLEX ASSESSMENT OF NATURAL AND ANTHROPOGENIC PRESSURE FOR WATER RESOURCES IN CENTRAL ASIA - KARATAL RIVER CASE STUDY

Proccedings of International Scientific Conference "RURAL DEVELOPMENT 2017" ◽

10.15544/rd.2017.123 ◽

2018 ◽

Author(s):

Zhumakhan Suleimenovich MUSTAFAYEV ◽

Jozef MOSIEJ ◽

Lya Tobazhanovna KOZYKEEVA ◽

Kurmanbek ZHANYMKHAN

Keyword(s):

Natural Environment ◽

Cost Effective ◽

Anthropogenic Factors ◽

Anthropogenic Pressure ◽

Ecological Stability ◽

Catchment Basin ◽

Natural Systems ◽

Catchment Areas ◽

Natural Landscapes ◽

The Impact

Development of the national economy in the Karatal basin river is characterized by the progressive involvement and development of the resource potential of natural landscapes, the current rate of utilization of which greatly enhances the anthropogenic impact on the natural environment. A significant impact on the formation of the ecological environment of natural landscapes is provided by the rural and water sectors, as well as by industrial facilities related to processing and mining. At the same time, on the one hand the economic activity of the man in the catchment areas of the river basin gives a certain positive effect, and on the other hand, it is accompanied by an unavoidable set of negative ecological consequences that complicate ecological situations in various ranks of natural systems. Such negative natural and man-caused process in human activity occurs as a result of inadequate knowledge of the regularities of interaction between natural and anthropogenic factors, about the processes developing in the natural environment in complex watershed management, which is one of the obstacles on the way to the creation of ecologically sustainable cost-effective water catchment systems. Scientific interest to the assessment of the ecological state of the catchments of rivers and the problem of their complex development have been appeared relatively recently which is explained by the increase in modern conditions of anthropogenic load on the catchment areas, the need to assess the impact of such pressures on the ecological stability of catchments and the emergence of the problem of ensuring the sustainable function of catchments. The catena concept was developed to analyze the regular variability of soil on the slope. The example of this approach consists first in a structural component, the recurring pattern of certain soils in a landscape transects in which every chain element has its place in the chain, a soil has it in a landscape areal. The object of the research is the catchment basin of the Karatal river with a length of 390 km, an area of 19.1 thousand km², which is formed by the merger of three rivers called Tekeliaryk, Chadzha and Kora, sources which are at an altitude of 3200-3900 m. The initial 160 km is mountain character, from the Zhungarian Alatau and below the confluence of Kara and Chizhe River overlooks a wide intermountain plain. Other tributaries are Kara, Terekty, Laba, Balykty, Mokur and the most abundant is Koksu. After the confluence of the tributary of the Koksu River, Karatal flows through the sandy desert of the Southern Balkhash. At a distance of 40 km from the mouth, the river has a delta area of 860 km 2. According to long-term observations, the average annual discharge of the Karatal River in the Ushtobe section is 66.7 m3/s or 2.1 km3/ year.

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Qualitative assessment of the impact of some anthropogenic factors on natural foci of tularemia in the Rostov agglomeration

I P Pavlov Russian Medical Biological Herald ◽

10.17816/pavlovj63519 ◽

2021 ◽

Vol 29 (3) ◽

pp. 347-354

Author(s):

Lyudmila V. Sudina ◽

Natalia L. Pichurina ◽

Anna P Khametova ◽

Elena P. Sokolova ◽

Igor' V. Orekhov ◽

...

Keyword(s):

Native Species ◽

Qualitative Assessment ◽

Anthropogenic Factors ◽

Federal State ◽

Circulation System ◽

Anthropogenic Pressure ◽

Rostov Region ◽

Field Samples ◽

Natural Foci ◽

The Impact

AIM: To qualitatively assess the impact of some anthropogenic factors (construction of industrial facilities, transport networks, intensification of agriculture) on natural foci of tularemia in the Rostov agglomeration. MATERIALS AND METHODS: The official data and reports of the Federal State Budgetary Institution Rosselkhoznadzor, the data of the Department of Rospotrebnadzor for the Rostov region, the Federal State Budgetary Institution Center of Hygiene and Epidemiology in the Rostov Region of Rospotrebnadzor were analyzed. Zoological and parasitological studies were carried out in accordance with modern regulatory documents in force. The detection of F. tularensis markers in field samples was carried out using serological and molecular genetic methods. RESULTS: It was found that the existing territories under natural protection of the Russian agglomeration restrict degradation processes, while maintaining the simultaneous coexistence of native species and synanthropic animals that make up the parasitic circulation system of the tularemia pathogen. CONCLUSION: The qualitative assessment of anthropogenic pressure/action can probably be interpreted as conditionally neutral. This could lead to potential risks of infection of the unvaccinated population of the Rostov agglomeration in natural foci of tularemia. The dynamism of the processes of anthropogenic action requires constant monitoring of the changes in the species diversity of carriers and vectors, their abundance, and infection in the natural foci of tularemia in the Rostov agglomeration.

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Interactions between deforestation, landscape rejuvenation, and shallow landslides in the North Tanganyika – Kivu Rift region, Africa

10.5194/esurf-2020-87 ◽

2020 ◽

Author(s):

Arthur Depicker ◽

Gerard Govers ◽

Liesbet Jacobs ◽

Benjamin Campforts ◽

Judith Uwihirwe ◽

...

Keyword(s):

Slope Failure ◽

Land Use Changes ◽

Extreme Rainfall ◽

Google Earth ◽

Shallow Landslides ◽

Extreme Rainfall Events ◽

Landslide Activity ◽

Erosion Rates ◽

The North ◽

The Impact

Abstract. Deforestation increases landslide activity over short, contemporary timescales. However, over longer timescales the location and timing of landsliding is controlled by the interaction between uplift and fluvial incision. Yet, the interaction between (human-induced) deforestation and landscape evolution has hitherto not been explicitly considered. We address this issue in the North Tanganyika-Kivu Rift region (East African Rift). In recent decades, the regional population has grown exponentially and the associated expansion of cultivated and urban land has resulted in widespread deforestation. On a much longer time scale, tectonic uplift has forged two parallel mountainous Rift shoulders that are continuously rejuvenated through knickpoint retreat, enforcing topographic steepening. In order to link deforestation and rejuvenation to landslide erosion, we compiled an inventory of nearly 8,000 recent shallow landslides in Google Earth© imagery from 2000–2019. To accurately calculate landslide erosion rates, we developed a new methodology to remediate inventory biases linked to the spatial and temporal inconsistency of this satellite imagery. We find that erosion rates in rejuvenated landscapes are roughly 40 % higher than in the surrounding relict landscapes, upstream of retreating knickpoints and outside of the Rift shoulders. This difference is due to the generally steeper relief in rejuvenated landscapes which more than compensates for the fact that rejuvenated slopes, when compared to similarly angled slopes in relict zones, often display a somewhat lower landslide erosion rate. These lower rates in the rejuvenated landscapes could be the result of a drier climate, the omission of earthquake-induced landslide events in our landslide inventory, and potentially a smaller regolith stock. More frequent extreme rainfall events in the relict zones, and possibly the presence of a thicker regolith, cause a stronger landslide response to deforestation compared to rejuvenated landscapes. Overall, deforestation initiates a landslide peak that lasts approximately 15 years and increases landslide erosion by a factor 2 to 8. Eventually, landslide erosion in deforested land falls back to a level similar to that observed under forest conditions, most likely due to the depletion of the most unstable regolith. Landslides are not only more abundant in rejuvenated landscapes but are also smaller in size, which may be a consequence of the seismic activity that fractures the bedrock and reduces the minimal critical area for slope failure. With this paper, we highlight the importance of considering the geomorphological context when studying the impact of recent land use changes on landslide activity.

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Mapping of the dilemma of mining against forest and conservation in the Lom and Djérem Division, Cameroon

Proceedings of the ICA ◽

10.5194/ica-proc-1-111-2018 ◽

2018 ◽

Vol 1 ◽

pp. 1-7

Author(s):

Mesmin Tchindjang ◽

Eric Voundi ◽

Philippes Mbevo Fendoung ◽

Unusa Haman ◽

Frédéric Saha ◽

...

Keyword(s):

Land Use ◽

Forest Cover ◽

Mining Industry ◽

Google Earth ◽

Colonial Period ◽

Mining Activities ◽

Geospatial Tools ◽

The Rich ◽

Legal Frameworks ◽

The Impact

Mining practices in Cameroon began since the colonial period. The artisanal mining sector before independence contributed to 11&ndash;20&thinsp;% of GDP. From 2000, the rich potential of the Cameroonian subsoil attract many foreign investors with over 600 research and mining permits already granted during the last decade. But, Cameroonian forests also have a long history from the colonial period to the pre-sent. However, mining activities in forest environments are governed by two different legal frameworks, including mining code i.e. Law No. 001 of 16 April 2001 organizing the mining industry and Law No. 94-01 of 20 January 1994 governing forests, wildlife and fisheries. Therefore, in the absence of detailed studies of these laws, there are conflicts of interests, rights and obligations that overlap, requiring research needs and taking appropriate decisions. The objective of this research in the Lom and Djérem division is to study, apart from the proliferation of mining li-censes and actors, the dilemma as well as the impact of the extension of mining activities on the degradation of forest cover. Using geospatial tools through multi-temporal and multisensor satellite images (Landsat from 1976 to 2015, IKONOS, GEOEYE, Google Earth) coupled with field investigations; we mapped the dynamic of different forms of land use (mining permits, FMU and protected areas of permanent forest estate) and highlighted paradoxically the conflict of land use. We came to the conclusion that the rhythm of issuing mining permits and authorizations in this forestall zone is so fast that one can wonder whether we still find a patch of forest within 50 years.

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STUDY OF FISH HELMINTHS SPECIES COMPOSITION IN THE MIDDLE STREAM OF HRAZDAN RIVER, ARMENIA

10.31016/978-5-9902340-8-6.2019.20.433-437 ◽

2019 ◽

pp. 433-437

Author(s):

Oganesyan ◽

Rukhkyan

Keyword(s):

Species Composition ◽

Silver Carp ◽

Practical Interest ◽

Body Cavity ◽

The Body ◽

Anthropogenic Factors ◽

Anthropogenic Pressure ◽

Middle Stream ◽

The Impact ◽

River Fish

The ichthyogelminthofauna of the Hrazdan River has been little studied. The aim of the work was to identify the species composition of helminths of fish in the middle course of the river Hrazdan. The study of the helminthofauna of river fishes is of scientific and practical interest, especially in view of the increasing anthropogenic pressure in this region. In 2018, 86 specimens of fish of 6 species from Cyprinidae family were examined from the middle course of the river using the generally accepted method of parasitological autopsies. The overall invasiveness of the fish with helminths was 36%. In fish, monogenes, trematodes, cestodes, and nematodes were identified. 8 species of helminths were recorded. They were localized in the lens of the eyes, on the gills, in the body cavity and in the intestines of fish. In the fauna of fish helminths, biohelmints of 7 species dominate. Of these, metacercaria diplop and plerocercoids ligul are more common. 5 types of worms are generalists. 5 species are allogeneic, 3 species - autogenous. The impoverishment of the species composition of fish helminths is obviously a consequence of the impact of negative anthropogenic factors. The ichthyofauna of the Hrazdan River is different at different sites. In the lower reaches of the river, it is represented by more than 30 species, including the silver carp, the eastern swift fish, the Kura barbel, the Sevan temple, the Angora goletsir. Upstream, the species composition of fish is declining: only a few species are recorded — the silver carp, the Sevan temple, the eastern swift fish, the Kura barbel, etc. (Pipoyan, 2012). The helminthofauna of the Hrazdan river fish is little studied. The literature contains isolated data from the 1980s: in a survey of 22 specimens of crucian carp metacercariae by diplopost with up to 100% invasion were detected, plerocercoids liguli botriocephalus (Vartanyan, 1993). In 2016, the helminth fauna of fish in the upper reaches of the Hrazdan River was studied: 8 species of helminthes were found, the fish invasion was 37% (Oganesyan, Rukhkyan, 2018).

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Global Flood Mapper: Democratising open EO resources for flood mapping

10.5194/egusphere-egu21-16194 ◽

2021 ◽

Author(s):

Pratyush Tripathy ◽

Teja Malladi

Keyword(s):

Disaster Response ◽

Flood Hazard ◽

European Space Agency ◽

Google Earth ◽

Data Availability ◽

Anthropogenic Factors ◽

Flood Mapping ◽

Flood Events ◽

Space Agency ◽

The Impact

Climate change has increased the frequency of flood events globally. Floods cause massive loss of life and cause the expenditure of billions of dollars. While it is important to curb floods caused by anthropogenic factors in the first place, it is equally important to reduce the impact in the aftermath of floods. The extent of past flood events is crucial for developing disaster management plans and flood hazard modelling. Due to the lack of capacity and availability of the funds with local officials, many past disasters remain unmapped and the information is just limited to total life loss and damage estimates.Satellite data has been widely hailed as an alternative to drone and aerial surveys. And recent advances in open Earth Observation (EO) data availability, for instance, the Sentinel-1 SAR data by the European Space Agency (ESA), and cloud processing platforms such as the Google Earth Engine (GEE) have opened unprecedented opportunities for using EO data for hazard and disaster response efforts. Recent literature in the field of EO is witnessing an increasing number of the Sentinel-1 and GEE combination for flood mapping.In the present work, we demonstrate the utility of a recently developed tool, the Global Flood Mapper (GFM), which is an open GEE application for rapid mapping of flood inundation extent using Sentinel-1 data. GFM uses a pre-flood time period to analyse numerous Sentinel-1 scenes of the same study area, this accounts for seasonal variation and has lesser noise as compared to other methods that use just one pre-flood scene. We map a couple of flood events across the globe to demonstrate the scalability and ease of using GFM. In addition, we analyse the flood hazard vulnerability of the state of Bihar in India using flood extent for the year 2018, 2019 and 2020 by delineating frequently flooding areas. This showcases yet another crucial utility of the GFM tool. GFM can support the flood extent mapping of the past events in addition to the rapid flood mapping of the current events, that could aid researchers and disaster managers for better flood preparedness and response.&#160;We access GFM through the link available on this public repository: https://github.com/PratyushTripathy/global_flood_mapper

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Three decades of landslide activity in western Nepal: New insights into trends and climate drivers

10.5194/egusphere-egu21-15848 ◽

2021 ◽

Author(s):

Alberto Muñoz-Torrero Manchado ◽

Simon Allen ◽

Juan Antonio Ballesteros-Canovas ◽

Amrit Dhakal ◽

Megh Raj Dhital ◽

...

Keyword(s):

Climate Change ◽

Slope Stability ◽

Google Earth ◽

Shallow Landslides ◽

Anthropogenic Factors ◽

Climate Change Signal ◽

Annual Number ◽

Landsat Images ◽

Intergovernmental Panel ◽

Landslide Activity

Landslide activity in the Himalaya region is hypothesized to have increased over the last decades, as suggested by exiting landslide databases and disaster inventories. This trend has been linked to an enhancement of heavy rainfall events under warming climate, but also to anthropogenic factors that influences the slope stability as well as to an increase of exposed of people and infrastructures in prone areas. Yet, as recognized by the Intergovernmental Panel on Climate Change (IPCC), such positive trends are still unclear, mostly due to the lack of baseline data with enough spatio-temporal resolution. Focusing on Far-Western Nepal, we draw on remote sensing techniques to create a multi-temporal regional landslide inventory for the period 1992-2018 over an area covering 6,460 km2. To this end, we systematically interpret geomorphologically high-resolution satellite imagery from Google Earth. Besides, we analyze multispectral differences from Landsat images to interannual date the initiation or reactivation of the interpreted landslides. This massive effort includes the digitalization of 26,350 landslide events, of which 8,778 were dated at an annual scale. These events serve as a basis for the analyses of landslide frequency relationships and trends in relation to annual precipitation and temperature datasets, derived from ERA-5 climate reanalysis. Our results show a strong correlation between the annual number of shallow landslides and the accumulated monsoon precipitation (r=0.74). Furthermore, warm and dry monsoons followed by especially rainy monsoons produce the highest incidence of shallow landslides (r=0.77). However, we find strong spatial variability in the strength of these relationships, which is linked to recent demographic development in the region. This highlights the role of anthropogenic drivers, and in particular, road cutting and land-use change, in amplifying the seasonal monsoon influence on slope stability. In parallel, the absence of any long-term trends in landslide activity, despite a widely reported increase in landslide disasters, points strongly to increasing exposure of people and infrastructure as the main driver of landslide disasters in this region of Nepal. Thus, our assessment could not determine evidence for any climate change signal related to landslide activity over this part of the Himalayas.

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