Mountainous Topography Research Articles

Use of flight tracking data to inform safety deficiencies for general aviation cross-country operations in challenging flying environments

Background: Air carriers, but not general aviation, have long employed in-flight data to identify risks/implement corrective measures for improved safety. Herein, using in-flight data, aircraft (in non-instrument-rated private pilots (PPLs) ownership) operations in two potentially hazardous environments (mountains, degraded visibility) were researched for safety practice deficiencies. Four questions were posed, the first two related to mountainous terrain operations: were aircraft (a) flown with hazardous ridge-level winds, (b) within gliding distance of level terrain? Regarding degraded visibility, did aviators (c) depart with low cloud ceilings (≤3,000 ft.), (d) fly at night away from urban lighting? Methods: The study cohort comprised: (a) single engine aircraft in sole PPL proprietorship (b) registered in Automatic Dependent Surveillance-Broadcast (ADS-B-Out) equipage-required locations prone to low cloud ceilings in three mountainous states. ADS-B-Out data for cross-country flights (>200 nm) were collected. Results: 250 flights (50 airplanes) were tracked (spring/summer 2021). For aircraft transiting areas subject to mountain winds influences, 65% completed one/multiple flights with potentially hazardous ridge-level winds. Two thirds of airplanes traversing mountainous topography would have, for at least one flight, been unable to glide to level terrain with a powerplant failure. Encouragingly, flight departures for 82% of the aircraft were with >3,000 ft. cloud ceilings. Likewise, flights for >86% of the study cohort were undertaken during daylight. Employing a risk scale, operations for 68% of the study cohort did not exceed low-risk (i.e., ≤1 unsafe practice) and high-risk flight(s) (three concurrent unsafe practices) were rare (4% of airplanes). In log-linear analysis, no interactions were evident between the four unsafe practices (p = 0.602). Discussion: Hazardous winds and inadequate engine failure planning were identified as safety deficiencies for general aviation mountain operations. Practical Application: This study advocates for the expanded use of ADS-B-Out in-flight data to inform safety deficiencies/implement corrective measures toward improving general aviation safety.

The scream is not silenced: A mountainous passage to Ettingerian environmental ethics

In the present geological epoch of the Anthropocene, the question increasingly arises of how to encounter the human-made planetary environment, which increasingly suggests being both a traumatized and traumatizing entity. For this endeavor, Bracha L. Ettinger’s matrixial theory offers an important reference point beyond prevailing environmental discourses and the notion of nature as total otherness. Lifting the split between the I and the Other, conceived through a “co-lapse of the gaze” and the praxis of “gazing-with,” this paper explores the radical rethinking of humans and nature as entangled in a psycho-planetary continuum and a shared unconscious sphere. Introducing such trans-subjective and trans-objective dynamics, aimed at unfolding a fragile and carrying relationship between humans and nature, the paper expands the Freudian psychic apparatus toward a mountainous psychic topography and draws, for the first time, the outlines of an Ettingerian environmental ethics.

Seismic Dynamic Response Analysis of Mountain Tunnels with Seismic Reduction and Isolation Measures

In this paper, the multi-domain indirect boundary element method (IBEM) is developed for the seismic response analysis of double-line mountain tunnels with seismic reduction and isolation measures. The dynamic response of the tunnel with seismic reduction and isolation measures under incident SV waves is analyzed, and the effect of the mountain topography on the tunnel is also investigated. Further, the effects of the isolation layer and the grouting reinforcement with different thicknesses on the seismic response of the tunnel are discussed in detail. The results show that the scattering of seismic waves by mountain topography significantly increases tunnel stress. In general, with the increase of incident frequency, the isolation layer will increase the peak displacement of the tunnel by about 12.7% at most, and the isolation ratio of the isolation layer on the tunnel stress exceeds 40%. The seismic reduction performance of the grouting reinforcement also depends on the incident frequency, and the amplitude decreases by approximately 20% at most frequencies. However, it is possible that the lining displacement under high-frequency waves becomes larger. This method can provide valuable insights and assessments for damage prediction.

Across-strike asymmetry of the Andes orogen linked to the age and geometry of the Nazca plate

Abstract The crest of the Andes—the trace of the highest mountain topography—weaves back and forth, in places near the coastline, in others farther inland. Its position reflects the asymmetric distribution of orogen mass and coincides with asymmetry of orographic precipitation. This coincidence is thought to reflect a primary influence of orographic precipitation on accumulated orogenic mass whereby the more erosive (wetter) side promotes crest migration toward the less erosive (drier) side. However, whether this remains the case after excluding tectonic controls on the size and asymmetry of the wedge is an open question. We assessed relationships between precipitation, erosion rates, and the macromorphology of the Andes. We find that precipitation rates cannot sufficiently explain orogen asymmetry after statistically controlling for the age or dip of the Nazca slab. Slab age and dip are known to primarily affect mountain building in the Andes by impacting stress and strain propagation into the retro-arc region, thus better explaining the position of the mountain chain within the orogenic wedge. Accordingly, using basin-wide erosion rate, topographic, and precipitation data, we find that precipitation possibly influences erosional efficiency in semi-arid Andean landscapes but falls short in explaining the variability of erosion rates in regions of high orographic precipitation. We conclude that the orographic effect cannot change the Andean macromorphology that is set by bottom-up tectonic processes.

Electrification and performance analysis of hybrid PV solar/wind energy system for remote and hilly area of Uttarakhand (India)

The need of electricity increases day by day, due to increase in population. With LPG cylinder rates touching stratospheric heights even though new LPG connections have been provided in the remote villages of Uttrakhand, people have no money to purchase the cylinders. Therefore it becomes a necessity to provide uninterrupted power to each family in each locality including remote and tribal’s of Uttarakhand so that they can cook their food on induction tops instead of shifting back to smoky ways of producing fire. This Paper is for analysis of power supply using Solar and Wind hybrid energy system in belts that lie in north-east of Uttarakhand. This area includes some part of Dehradun, Tehri, Pithoragarh, Champawat, Bageshwar, Almora, some part of Nainital and Rudraprayag. There are some hilly/tribal areas where population is less than 30 persons per square kilometers. People in such areas live in scattered homes. The entire area having mountainous topography results in very costly supply of electricity to each and every home. Further continuous supply of electricity to these remote areas of Uttarakhand is also a big challenge. Hybrid Solar PV and Wind Energy is very useful for these areas. For rural area of Uttarakhand it plays a major role to fulfill the requirement of energy. Electrification of households in rural areas and isolated regions results in balanced economic development. India grows with a high population growth rate of 0.95 % in current year but still parts of rural India and isolated regions do not have the accessibility to electric power. This study focuses on the feasibility study of a hybrid PV-Wind-Energy power system for rural electrification in Uttarakhand.

Field measurement of local wind environment on the approach deck of a suspension bridge in mountain terrain

The local wind environment above the bridge deck affects the aerodynamic characteristics of vehicles, thus affecting the driving safety of the bridge deck. Influenced by the mountain topography and the bridge deck's ancillary facilities, the local wind environment above the bridge deck is complex and changeable, and its impact on the bridge deck traffic can not be ignored. In order to accurately evaluate the local wind field parameters, a monitoring system of the local wind environment is developed. Utilizing the monitoring system, wind parameters above the approach deck of a long-span suspension bridge in a mountain area are measured. The relationship of wind characteristics between the incoming flow and the wind above the bridge deck is investigated. Results show the significant difference between the local wind environment above the bridge deck and the incoming flow's characteristics; the wind profile above the bridge deck does not follow the exponential distribution; the equivalent height of the wind load on the vehicle is higher than the vehicle's gravity centre. This study is relevant for studying the local wind environment, driving safety, and serviceability of long-span bridges in mountainous areas.

Multi-source rainfall merging and reservoir inflow forecasting by ensemble technique and artificial intelligence

Study regionThe Shihmen reservoir, the second largest reservoir in northern Taiwan, is flooded frequently, and featured by short period of flood peak due to uneven distribution of rainfall and mountainous topography. Study focusWe proposed a novel streamflow-oriented ensemble recurrent neural networks (ERNN) method to merge three precipitation products, namely gauge measurements, radar and satellite rainfall products. We analyzed (1) the effect of artificial intelligence method for bias correction of precipitation products with reference to streamflow, (2) the comparison of two widely used arithmetic average (AA) and Bayesian model averaging (BMA) methods with ERNN, (3) the performance of merged rainfalls and the original three precipitation products in inflow forecasting during 13 typhoon events. New hydrological insightsWe found that all precipitation products are biased and can be appropriately adjusted with an improvement in inflow forecasting of about 2.5 %, 21.8 % and 60.7 % for gauge, radar and satellite rainfall products in terms of RMSE. After rainfall merging, RMSE for radar and satellite are further improved by 14% and 36% at least. ERNN merging method indicates that the optimal merging weights for gauge, radar and satellite are within the range of 0.52–0.56, 0.35–0.39 and 0.08–0.09, respectively according to 95 % confidence interval. The merged rainfall product skillfully predicts the inflow with a lead time of five hours, and ERNN merging method is superior to traditional AA and BMA methods, with NS up to 0.85 and CRPS reduced by near 50 % compared to BMA. Additionally, ERNN is found to capture the peak times and peak flows with the smallest error. Overall, this study provides a potential approach to merge multiple rainfall products and to obtain the effective rainfall by fitting the hydrological responses over mountainous watersheds, where observational biases may frequently occur in gauge, radar and satellite measurements.

Recent Applications of Flash Flood Hazard Assessment Techniques: Case Studies from Egypt and Saudi Arabia

Flash floods are severe natural disasters due to their suddenness, frequency, and destruction. Every year, flash floods occur in Egypt and Saudi Arabia, which are located in the heart of the Middle East. Extensive areas in Egypt and Saudi Arabia are covered by mountainous topography. Intense rainfall can generate flash floods with their magnitude dependent on geomorphology and storm characteristics. Flash flood hazard assessment is a feasible way to mitigate potential damage and losses. Illumination, review, and comparison of assessment techniques of flash flood hazards represent an urgent necessity to evaluate advances and challenges in this discipline. Google-scholar and Scopus were used to collect 50 recent scientific papers, most of them published between 2011 and 2021, using the keywords: floods, hazards, assessment, Egypt, Saudi Arabia. Remote Sensing (RS) and Geographic Information systems (GIS) are the cornerstones of these studies, which include the Digital Elevation Model (DEM) and geoprocessing tools. The two items facilitate the calculation of morphometric parameters. Dividing the area and determining the hazard level were the main steps in flash flood hazard assessment. The considered studies relied on varied sets of morphometric parameters that ranged from 3 to 24 morphometric parameters. Area, ruggedness ratio, basin shape index, stream frequency, slope index, and drainage density are the common parameters in the assessment of flash flood hazards. In a flood zone, buildings made from brick have better sustainability in terms of both global warming mitigation and life cycle cost than other materials. Future studies are essential to illustrate the relationships between different morphometric parameters and flash flood hazard degree through field data and define a reliable unified set of morphometric parameters to assess the flash flood hazard degree.

Spatial and Temporal Characteristics of High-Temperature Heat Wave Disasters in Chongqing

In the background of global warming, heat wave disasters have become more frequent globally, and mountainous cities are more seriously affected by heat wave disasters due to the special features of topography and urban morphology. This paper analyzes the temporal and spatial distribution characteristics of heat wave disasters in Chongqing, a mountainous city. The results shows that heat wave disasters in Chongqing tend to increase overall and decrease locally before increasing. Significant growth in heat waves since 2010 and time series model prediction analysis shows that Chongqing will face more severe heat waves in the future. The spatial distribution of heat wave disasters varies significantly, high in the middle and low at the ends. There is a tendency for the center of heat wave disasters to shift from the south-central part of Chongqing to the northeast. In addition to the influence of atmospheric circulation and mountain topography, the causes are also positively related to urban development intensity and urbanization trends. It is necessary to develop specific control and management measures for heat waves depending on the characteristics of them. The take-home message of the study is the spatial and temporal trends of heat waves in Chongqing to provide a theoretical basis for high-temperature mitigation.

Pelatihan Diversifikasi Jamur Tiram Sebagai Produk Olahan Makanan di Kecamatan Pamboang Kabupaten Majene

Most areas in the Pamboang sub-district have a hilly and mountainous topography with a tropical solar climate. The fertile natural conditions are very supportive making it a potential area for agriculture and as a place for mushroom cultivation. Urawa oyster mushrooms are the first group that is productive in developing oyster mushrooms in Majene Regency. However, the number of oyster mushrooms produced is not in line with public demand. The indigenous people of Majene are still unfamiliar with the processing and taste of oyster mushrooms. This community service campaign aims to introduce oyster mushrooms as a diversification of processed food. The method of community service activities uses counseling, training and mentoring methods. This activity was attended by 30 participants from the general public, 2 traditional leaders, and 10 students of the Biology Education study program at the University of West Sulawesi. The training activity was carried out by involving all participants in making various processed oyster mushrooms such as crispy mushrooms, meatballs, nuggets, crackers, and shredded. These processed products can be stored for a long time, are practical, and are in the form that popular among the public. In addition, assistance is carried out in obtaining Urawa product P-IRT permits at the health office. Diversification of processed mushroom products will greatly help increase the marketing of oyster mushrooms and help the partner's economy as a creative business. The implementation of the activities was very good as indicated by the increase in the knowledge and skills of the participants before and after the training.

Natural Disaster Risk Assessments for Pine Honey Apiaries in Muğla, Turkey

Since Muğla province has 90% of the world's total pine honey production, ensuring efficiency and economic income requires the determination of measures for apiary locations and estimation of risks. However, ensuring development and productivity requires identifying natural disasters susceptibility such as forest fires and floods to maintain productivity. Muğla province has a high forest fire potential due to its dense forest cover and approximately 200 forest fires occur each year. Forest fires are one of the main factors that threaten apiaries, as there are a lot of apiary places (approximately 15,000) in forests for pine honey. On the other hand, due to the mountainous topography and high precipitation rate of Muğla, the province has a high rate of flood formation (20 per year), which threatens the hive sites by destroying the entire colony. In this study, Apiary Locations Risk Index (ALRI) was carried out to guide the insurance process for apiary locations by applying the Forest Fire Risk Index (FFRI) and the Flood Hazard Risk Index (FHRI). Determination of forest fire risk zones and flood hazard maps requires environmental, forestry, topographic, economic and meteorological parameters to be handled within a decision support platform. For this purpose, Analytical Hierarchy Process (AHP) technique supported by Geographic Information System (GIS) was used in the creation of sensitivity maps. As a result, 1533.40 ha (11.82%) of the study area was determined as extremely risky areas for apiary areas. The results were confirmed with 1454 forest fire sites and 20 flood hazard sites where the Eşen, Dalaman, Çine, Sarıçay, Akçay, Kamiişdere and Namnam rivers were stated to be highly susceptible to flood hazard.

Spatio-Temporal Analysis of Valley Wind Systems in the Complex Mountain Topography of the Rolwaling Himal, Nepal

The diurnal, seasonal, and spatio-temporal characteristics of local wind systems in a steep mountain valley in Nepal are analyzed with the identification of valley wind days (VWDs). Distributed across the Rolwaling Himal valley in Nepal between 3700 and 5100 m a.s.l. at eight automated weather stations (AWSs), meteorological data between October 2017 and September 2018 were examined. VWDs were classified by means of ERA5 reanalysis data and in situ observations, employing established thresholds using precipitation, solar radiation, air pressure, and wind speed data at different pressure levels. Thus, overlying synoptic influences are highly reduced and distinctive diurnal patterns emerge. A strong seasonal component in near-surface wind speed and wind direction patterns was detected. Further analyses showed the diurnal characteristics of slow (approximately 0.5–0.9 m s−1), but gradually increasing wind speeds over the night, transitional periods in the morning and evening, and the highest averaged wind speeds of approximately 4.3 m s−1 around noon during the VWDs. Wind directions followed a 180∘ shift with nocturnal katabatic mountain winds and inflowing anabatic valley winds during the daytime. With AWSs at opposing hillsides, slope winds were clearly identifiable and thermally driven spatio-temporal variations throughout the valley were revealed. Consequently, varying temporal shifts in wind speed and direction along the valley bottom can be extracted. In general, the data follow the well-known schematic of diurnal mountain–valley wind systems, but emphasize the influence of monsoonal seasonality and the surrounding complex mountain topography as decisive factors.

Individualized Community-Led Drinking Water Supply Projects in Rural Nepal

Despite access to water being a human right upheld by the United Nations, many residents in Nepal have limited access to safe drinking water due to factors including insufficient government assistance, the country’s mountainous topography, and devastating natural disasters. This paper examines the differences in effectiveness and sustainability in clean drinking water supply (DWS) systems in rural areas of the country that are either provided by the government or by local and international Non-Governmental Organizations (NGOs). I argue that drinking water supply projects that are conducted using an individualized community-led methodology by international and local NGOs working in partnership are more effective and sustainable than generalized methodologies often employed by the government, and positively contribute to other areas of development including gender equality. To do this, I look specifically at the approaches taken by the NGOs Nepal Water for Health (NEWAH) and Engineers Without Borders (EWB) in providing drinking water supply systems to rural communities in Nepal. Critically examining the outcomes of the differing methodologies that are employed to provide access to clean drinking water in this context is important in facilitating the achievement of the United Nation’s Sustainable Development Goal of safe and affordable drinking water for all.

Analisis faktor internal dan eksternal pengembangan perkebunan rakyat kopi Arabika di Kabupaten Pegunungan Arfak Provinsi Papua Barat

Arfak Mountains Regency is part of West Papua Province with an undulating to mountainous topography that spreads at an altitude of 800 – 3,000 m above sea level with the main livelihood of its community is farming highland vegetables. This region has a very suitable and potential climate for the development of Arabica coffee. Arfak Mountains Regency also has 2 lakes at an altitude of 2000 m above sea level, so the existence of coffee plantations can support the development of ecotourism in this area. The development of community coffee plantations is not as good as cocoa plantations. This is presumably due to the difficulty of the transportation of marketing results in the past. However, in line with the current infrastructure development, regional development progress, and the growth in the coffee economic value, the development of coffee plantations based on community plantations require significant attention. To be more focused on the development of arabica coffee in the Arfak Mountain Regency, it is necessary to be attentive to internal and external factors as the basis of policy making. This study aims to analyze internal factors (IFE) and external factors (EFE) in coffee farming communities in Anggi Gida District and Anggi Giji District. The results of the IFE and EFE analysis show that farmers in Anggi Giji District have more opportunities (quadrant I: 2.79;2.79) to develop coffee than farmers in Anggi Gida District (quadrant I: 2.61; 2.25). Based on the SWOT analysis both in Anggi Gida District and in Anggi Giji District, the development of Arabica coffee community plantations must implement a strategy to optimize land (S1, S2, O2, O3, O4), improve technical skills (W3, O1, O2, O4), optimize farmer group institutions (S3, S4, T1, T2, T3, T4), and open a marketing network (W2, T3, T4).

ANALISIS SPASIAL DAERAH POTENSI RAWAN LONGSOR DI KOTA AMBON DENGAN MENGGUNAKAN METODE SMORPH

The geographical condition of Ambon City, which is 75% a hilly area resulted in most communities building in marbled areas with slopes above 20%, which has the potential to threaten life and landslide disasters. This study simply looked at the influence of slopes and slope shapes in Ambon City that can be analyzed using geographic information systems (GIS) to map areas that have the potential for landslides. Identification and mapping of potential landslide areas have an important role as an effort in overcoming and anticipating the occurrence of landslide disasters. This study aimed to analyze the spread of potential landslide areas in Ambon City based on the results of SMORPH modeling. The study used the slope morphology or SMORPH method, which has a better degree of accuracy than the Storie Index and SINMAP methods to identify and classify potential landslide areas based on the matrix between slope shape and slope angle. This study resulted in 4 levels of landslide potential areas, namely very low, low, medium and high potential. Areas with high landslide potential dominate the northern and southern parts of Ambon City. In the region, most landslides occur in the form of sunken and convex slopes. The region has a hilly and mountainous topography with a steep slope. The results of this research using the SMORPH method can illustrate that the slope of the increasingly higher slope accompanied by the shape of a convex or concave slope will cause the potential for landslides that are higher in the region.

Simulation of thermal power plant source contribution to ambient air concentration in Cam Pha City, Quang Ninh province using AERMOD dispersion model

Cam Pha, the home of three major thermal power plants including Cam Pha, Mong Duong I and Mong Duong II, is one of the most important industrial cities in the North of Vietnam. Air pollution due to stacks emission is the biggest problem threatening Cam Pha City's sustainable development. In this study, the AERMOD modeling system was used to evaluate the impact of the stack emission by the thermal power plants on the ambient atmospheric environment. The maximum 1-HR, 24-HR, 99th percentile and annual average concentrations of TSP, SO2 and NO2 were simulated within the 40x40 km domain of 100x100 m grid spacing with the hourly meteorological data taken from 2018 to 2020. Air dispersion simulation is performed on the observed background gas concentration of the everyday environment. Hourly emission data of 10 primary stack sources of 3 factory groups were used as input data. The simulated spatial distribution of gases indicates the strong fluence of the mountainous topography on the dispersion of stack emission. Results also revealed that the maximum short-term stack emission at ground-level concentrations of SO2 and NO2 are much higher than the national standard, thus raising the risk of severe pollution. TSP pollution is less severe than SO2 and NO2 but still at a dangerous level. Since Cam Pha locates by the East Sea with the prevailing wind is heading northeast and east directions. The annual average concentrations of these pollutants indicate that the high terrain areas at the south and northwest of Cam Pha City, which block the flow of the stack emission, are the most affected regions by exhausted gases from industrial stacks.

Analogue sandbox modeling of orogenic wedge front faulting: Roles of inherited fault zones and topographic loading

Earthquakes reported in the frontal belts of active orogenic wedges such as the 2013 Mw6.6 Lushan and 1999 Mw7.6 Chi-Chi earthquakes, highlight the importance of loading exerted by mountainous topography and inherited fault zones. However, their effects on formation and activation of these wedge front fault systems remain poorly understood. This study presents three sets of sandbox experiments in which topographic loading and geometry of inherited faults were first separately investigated, then explored jointly. Experiments show that smaller topographic loading favors gentle-dipping wedge front thrusts, while larger topographic loading promotes the development of steep wedge front faults. Introduced as zones of frictional weakness, all inherited faults promote deformation localization, though the steep ones are characterized by buttressing nearby rather than direct slip on themselves. When the two factors were tested integrally, four major deformation modes arose, including (1) direct reactivation; (2) fault truncation in the initial stage of compression; (3) stacking of small thrusts against the inherited fault and possible truncation in a later evolutionary stage; (4) behavior as a fossil structure. These modes show differences not only in first-order deformation styles, but also in the distribution of secondary structures, defining a basic framework and providing new guides for the interpretation of complex wedge front fault systems and their activities, in areas such as the Longmen Shan (eastern Tibet), the Tian Shan and the western margin of the Taiwan orogen.

Co-evolution of the Cenozoic tectonics, geomorphology, environment and ecosystem in the Qinling Mountains and adjacent areas, Central China

The Qinling Mountains stretching from east to west in Central China are an important geological and geographical boundary in the China Continent and even the East Asia Continent. The mountains were originally formed by the collision between the North and South China Blocks during the Paleozoic and Triassic, and overprinted by the Late Mesozoic intracontinental orogeny. Since the Cenozoic, the Qinling Mountains have experienced rapid uplift, forming a great and high mountain range, which has become the geographic boundary between the Northern China and Southern China. It has an important impact on the north-south climate differentiation in the China Continent, and plays a decisive role in the north-south differentiation of ecological environment, economy, and culture. It has also profoundly affected the natural environment and biodiversity pattern in China and even East Asia. This contribution provides an overview of the relationship between the Cenozoic tectonic uplift, geomorphic evolution and biodiversity in the Qinling Mountains, as well as its boundary effect on climatic and environmental changes. It describes the topographic changes under the control of tectonics, as well as the responses of climate, environment and biological evolution to the topographic changes. Due to the high mountain topography, the Qinling Mountains act as a climate barrier between the Northern and Southern China Continents. It shows the vertical climate zoning, and separates a temperate monsoon climate to the north and a subtropical monsoon climate to the south. The unique geographical location and diverse climate types make the Qinling Mountains a unique area of biodiversity in the world. All the available data indicate the co-evolution between the Cenozoic tectonics, geomorphology, environment and ecosystem in the Qinling Mountains and adjacent areas.

Origin of Late Quaternary Gravel and Drainage Basin Expansion in the Northern Chinese Tian Shan: Insights From Sediment Provenance Analyses

AbstractThe source‐to‐sink relationship between a sedimentary basin and its adjacent mountain range is vital for understanding the genesis of piedmont coarse‐grained sediments and the evolution of mountain topography. By integrating zircon U‐Pb dating and heavy mineral assemblage analyses on 15 samples, this work focuses on the change of the provenance with time in the Urumqi River Neogene‐Pleistocene continental sequence in the northern Chinese Tian Shan foreland, which has been chronologically constrained to range from ∼6.8 to ∼0.55 Ma. The results of the integrated provenance analyses reveal two shifts in provenance during the periods of 4.6–2.5 and 0.9–0.55 Ma, yielding new zircon U‐Pb age signals from the glacier‐covered headwaters of the Urumqi River. These two identified provenance adjustments are causally related to enhanced glacial erosion in the high mountain. We propose that enhanced glacial erosion could have caused southward expansion of the Urumqi River drainage basin, increased production of coarse‐grained materials with new zircon U‐Pb age signals, and finally accumulation of piedmont alluvial gravel. The observed topographic and sedimentary responses to enhanced glaciation could have been common phenomena during the late Quaternary in alpine areas, where a large number of alluvial fans are widely distributed like aprons along the mountain front, as seen in the piedmonts of the Tian Shan in the arid interior of Asia.

Guiding Conservation for Mountain Tree Species in Lebanon

The objective of this study is to contribute to the conservation of upland tree species in the face of climate change. We used a conservation index to prioritize the areas and populations of three conifer species in the mountains of Lebanon. This conservation index integrates (1) mountain topography to identify areas that could provide a suitable microclimate, (2) genetic diversity to assess the adaptive capacity of populations in these mountain areas, and (3) a hypothetical climate change scenario that could affect this Mediterranean region. The idea of this index is to prioritize protected areas based on a match between the relevance of the area to be protected and the populations that need local and long-term protection. The stronger the match, the higher the priority of the area to be protected. We applied this conservation index to 36 populations of 15 fir, 15 cedar, and 6 juniper. These populations were genotyped by different authors whose published data we used. The results show that 10 populations of the 3 species have a very high index and 9 others have a lower but still high index, indicating a high conservation priority. These 19 populations occur in 5 different areas that we delineated and that form a network along the Lebanon Mountains. We hypothesize that the conservation of these 19 populations across the Lebanon Mountains could contribute to the long-term sustainability of the 3 species in the face of a 2 °C increase in mean seasonal temperature and a 20% decrease in seasonal precipitation compared to the current climate.