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During the 5th and the 6th centuries, the prosperous city of Gaza gained its reputation as a port of call for merchants and pilgrims to the Holy Land and as a port for shipment of products to the west. The economic hinterland of Christian Gaza included villages, monasteries and various agricultural estates that provided agricultural merchandise to the city residents (fruits, vegetables, field crops), along with the famous “Gaza Wine” exported across the Mediterranean. The houses in these settlements were built of unfired mud-bricks, while water was collected from roofs and courtyards into underground cisterns. The cisterns were typically dug into the soil and made of a hardy mixture of cement, rubble, and gravel and coated with layers of hydraulic plaster. The cisterns were cylindrical, with a base diameter of 3-4.5 meters and a maximal depth of ca. 6-8 meters. About a meter below the rim, the cylinder structure tapered upwards into a cone shape, up to a diameter of 0.5 meters, where a stone slab with a square opening covered the cistern.This study aims to examine to which extent the abandonment of agricultural fields in the late Byzantine - early Muslim period caused significant landscape and soil properties change.We mapped ca. 150 water cisterns, typical of the period. Most cisterns are located north of the Nahal Gerar channel and along the lower catchment of the Nahal Besor. Mean annual precipitation in the area is 300-350 mm/year. Streams are ephemeral, characterized by flash floods during the winter.While almost nothing remained of the flourishing above-ground settlements, soil erosion exposed the cisterns, which now serve as well preserved indicators of the presence and location of Late Antique houses and villages. The abandoned water cisterns protrude above the surface and may enable us to calculate the erosion rates since the settlement collapsed. Study results indicate that the abandonment of agriculture intensified soil erosion: rates of erosion along the steep (10-20%) river banks and gullies are up to 2.5 m (1.7 mm/yr), while along the interfluves and over the low-angle slopes (2-5%) rates of erosion reach 1.2 m (0.8 mm/yr).Soil properties were also affected by human activity. In the Horvat Gerarit area, soil results from mud-brick degradation. Field identification is based on (1) relatively increase of fine fraction (clay and loam) within the villages sites, while median values changes from loam within the mud-bricks, to medium-sand over the agricultural fields; (2) mulch, that was added to the bricks to reduce cracking and increase tensile strength is incorporated into the soil; (3) direct observations of several degraded bricks into the soil.

Rock fragments in soil and on the soil surface affect key soil hydrological processes, including water repellency, thermal properties physical degradation, erosion, and productivity. The severe wildfire at Mt. Carmel, Israel, in 2010, caused massive destruction of carbonate rocks. The thermal shock caused extreme exfoliation, producing large and flat clasts, affecting rocks to a depth of up to 20 cm. A decade after the fire, most flakes and spalls disappeared from the rock outcrops and adjacent soils. From these observations, this study pursued two objectives: (a) to monitor and analyze the spatio-temporal distribution of the disintegrated flakes 10 years after the fire and (b) to test the hypothesis that fires contribute to increased soil stoniness via physical and chemical flake erosion. This research showed that after a decade, most of the spalled surface on the burned outcrops was lost, broken down and pulverized, exposing new rock surfaces to atmospheric and weathering processes. The most prominent effects were changes in surface stoniness on the rendzina soils over the chalks, while there was less impact on the dolomite and limestone samples. The stoniness of the non-burned chalk was 23-39% and increased significantly to 69-86% in the burned area. Chalk erosion produced large (>16 mm, median 8-16 mm) and abundant gravel, suggesting fragmentation of large spalls, and particles that lost their bladed shapes becoming oblate and equant. While earlier works suggested that increasing rock fragment cover is often associated with the removal of fine particles, our results showed a substantial increase in rock fragments due to fire-induced exfoliation of rock surfaces, leading to long-term changes in soil properties. We therefore propose that the size, shape, and spatial distribution of rock fragments should be considered when examining the effects of rock fragments on hydrological and geomorphological processes or on post-fire soil rehabilitation.

The Eastern Alps are an important tourist destination and attract many visitors every year for their scenic beauty, sports attractions and rich cultural heritage. Tourism is an important source of income and contributes to the revival or maintenance of local traditions. However, tourism also has potential negative impacts on the regions, for example Austria's largest forest fire in Hirschwang near Reichenau an der Rax (district of Neunkirchen) in the period 25.10.2021 to 6.11.2021 was anthropogenically triggered by tourists.In addition to the anthropogenic factors, the increase in extreme weather events caused by climate change and its scale dependent variations are a major challenge in the preparation of wildfire risk maps.Wildfires in steep Alpine valleys behave differently than those on flat or moderate inclined slopes. The present work describes a wildfire that occurred in August 2018 in a famous world-heritage site in Austria (Melzner et al. 2019), which was presumably initiated by a carelessly discarded cigarette or the reflection of a broken glass bottle at the foot of the rockwall. Indicators of fire severity and rockfall occurrence during and after the fire are described.The vertical rockwalls, the anabatic winds and patchy vegetation pattern, caused an upward jumping of the fire resulting in a spotty fire pattern. This most probably resulted in spatially varying fire intensities, and consequently highly heterogenic changes in soil and rockmass structure. The wildfire clearly showed that wildfires can have a significant impact on ecosystems and pose a high risk to settlements in the Alpine area. The rockfall hazard and risk assessment conducted in 2014 (Melzner 2015) enabled a fast decision making as part of an emergency response during and after the wildfire catastrophe in terms of identification of possibly endangered houses and planning of preliminary rockfall preventive measures.

While most of the scientific effort regarding wildfires has predominantly focused on fire effects on vegetation and soils, the role of fire as an essential weathering agent has been largely overlooked. This study aims to evaluate rock decay processes during wildfires, in relation to ground temperatures and rock morphologies of limestone, dolomite, and chalk. In 2010, a major forest fire in Israel caused massive destruction of the exposed rocks and accelerated rock weathering over the burned slopes. While a detailed description of the bedrock exfoliation phenomenon was previously reported, here, we conducted an experimental open fire to determine the temperature and gradients responsible for boulder shattering. The results show ground temperatures of 700 °C after 5 min from ignition, while the peak temperature (880 °C) was reached after 9 min. Temperature gradients show a rapid increase during the first 5 min (136 °C/min), moderate increase during the next 4 min (43 °C/min), and slow decrease for the next 9 min (25 °C/min). After 12 min, all boulders of all formations were cracked or completely shattered. The behaviour of carbonate rocks upon heating was studied to identify the erosive effects of fire, namely the formation of new cracks and matrix deterioration.

In the Eastern Alps no previous research focused on the impact of wildfires on the occurrence of rockfalls. The investigation of wildfires and post-wildfire rockfalls gains new importance with respect to changes in weather extremes and rapid social developments such as population growths and tourism. The present work describes a wildfire that occurred in August 2018 in a famous world-heritage site in Austria. Indicators of fire severity and rockfall occurrence during and after the fire are described.

During the last 150 years, various archaeological excavations and surveys revealed approximately 900 rock-cut tombs in the extensive necropolis surrounding ancient Jerusalem, dated to the late Hellenistic and Early Roman periods. The research goals are to examine the spatial distribution of these tombs in relation to the lithological units and rock hardness and to examine the diverse methods by which the ancient masons solved various lithological defects they encountered during the tomb excavation. We used field observations and Schmidt hammer tests to determine the rock hardness and the lithological properties. Our study demonstrates that the substrate played a crucial role in the establishment of the city and residents’ living conditions and that the presence or absence of caves in certain areas can be explained lithologically. Most tombs found west of the city were excavated in the Weradim Formation (13.7%); those found north of the city were mainly hewn into the well-bedded Nezer Formation (20.7%); and the tombs hewn east or south of the ancient city mainly met the soft Menuḥa Formation (56%). Excavating in the hard limestone of the Shivta Formation required high levels of effort and funding and, therefore, the number of tombs is limited (3%). In some cases, owners of estates located in soft lithologies granted burial rights to additional families, as proved by the large number of tombs and the clusters of burial systems in the Menuḥa Formation. Rock surfaces are mostly decayed by chemical dissolution, enhanced by structural fissures in the rock. Condensation corrosion and excess moisture were observed on the ceilings of some structures, along with bio-erosion. Two types of defects are common in the local rock: (a) major defects, endangering the stability of the rock-cut chamber that required complementary building with ashlar stones and (b) superficial defects that required only aesthetic solutions.

Severe fires accelerate rock weathering by spalling and exfoliation, creating abundant peels, flakes or spalls. In the following years, these spalls serve as physical traps which accommodate fine particles of dust, ash, organic matter, etc. We searched for traces of ash trapped under the spalls, after four major fires: 1989, 2005, 2010 and 2015 in Israel. Samples were collected beneath the spalls that formed on the rock outcrops, and in the immediate vicinity above and below them. Three laboratory analyses were performed: pH, EC and color. Five mineral/organic compounds were measured across the Mid-Infrared (MIR) spectral region at diffuse reflectance infrared Fourier transform mode: Hydroxylapatite (HAp), charcoal, organic carbon, montmorillonite and kaolinite. Several statistical analyses were performed: MANOVA, PCA and silhouette analysis on K-means clustering. The results show evidence of ash trapped under the spalls formed during the 2005 and 2010 fires, 6 to 11 years after the fires. Charcoal presence is evident, as well as increased amounts of HAp and organic carbon. In the exposed soil above or below the burned rock outcrop, these values are lower. Negligible amounts of ash were measured 27 years after the fire. In the 2015 burned outcrop, large amounts of charcoal were found above and below the outcrop, but not under the spalls. It seems that on the carbonate slopes of Israel and under Mediterranean climate, the time required for spalls to begin functioning as traps is longer than one rainy season, while ash traces are preserved in these traps for a period of two-three decades.

Long-term fluvial incision processes and corresponding geomorphic evolution are difficult to quantify, especially in complex systems affected by lithological and tectonic factors. Volcanic landscapes offer the most appropriate environment for the study of landscape evolution, as there is a clear starting time of formation and the lithology is homogenous. In the present study we aim to: (1) analyse the interplay of construction and incision processes throughout eruptive activity; (2) study fluvial erosion processes; (3) analyse sedimentary and volcanic lithological responses to channel erosion; and (4) calculate the incision rates in young basaltic bedrock. We have integrated existing and new 40Ar/39Ar ages of lava flows with estimates of channel geometry and tectonic activity, and considered process geomorphology concepts, to fully understand evolution of a bedrock channel incised at the boundary between basalts and sedimentary rocks with coeval active volcanic processes forcing drainage evolution. Our findings indicate that the Sa'ar basin evolution is controlled by: (1) rock strength of the mixed lithology; (2) alternating cycles of volcanic activity followed by erosion and incision; and (3) the Plio-Pleistocene uplift of Mt. Hermon. The carbonate slopes composing the southern flank of Mt. Hermon are moderate (18–26%) while the basalt slopes deriving from the Golan Heights are much steeper (26–51%). The highly erodible sedimentary rocks at Mt. Hermon's piedmont accelerated river incision, shaping a 650 m wide by 100 m deep canyon. Inside the canyon, the steep channel slope (8.6%) enables downstream movement of large boulders, including autochthonous mega-blocks (D90 size > 2.5 m); 24 knickpoints were identified using DS plots, developed within a knick zone over a distance of 6 km. The brittle and porous structure of the rubbly and blocky interflow layers (clinkers), interbedded between two massive basalt flows, enhances erosion and accelerates scouring of the plunge-pool bottom and walls. Three volcanic phases shaped the Sa'ar basin: (1) The 3.25 Ma Cover Basalt flowed over large areas of the Levant and reached up to the northern Golan; (2) Dalwe Basalt was emplaced between ~ 1.2 Ma and ~ 750 ka, from vents including Mt. Qatzaa and Mt. Odem, and extended to Mt. Hermon covering sedimentary cuestas; (3) Ein Zivan Basalt (including the Sa'ar Lava Flow – the youngest basalt flow known in Israel) erupted before ~ 110–120 ka and quickly accumulated at least three distinct flows into the deeply incised Paleo-Sa'ar canyon, refilling the canyon to a height of ~ 50 m. Rates of incision are consistent with other rivers draining the Golan Heights. The total incision rate of the Sa'ar channel during the last 760 ka is at least 19.7 cm/ka. Over the past 100 ka, the incision rate was 22–30 cm/ka and the back-erosion of the Sa'ar highest knickpoint occurred at 68 cm/ka. Our findings reflect the latest evolution history of a special, mixed lithology channel, developed at the border of a large basaltic province, in an active tectonic environment. The results suggest that fluvial adjustment of basalt-limestone rivers is determined first by the interplay of construction and incision processes throughout alternating cycles of volcanic activity and quiescence. The lithology is an extremely important factor determining the type and rate of erosion. While the tectonic factor might determine the basin relief and slope, the lithological factor accelerates erosion and river incision.

The severe wildfire at Mt. Carmel, Israel, in 2010, caused massive destruction of carbonate rocks. The thermal shock caused extreme exfoliation, producing large and flat clasts, affecting rocks to a depth of up to 20 cm. A decade after the fire, most flakes and spalls disappeared from the rock outcrops and adjacent soils. From these observations, this study pursued two objectives: (a) to monitor and analyze the spatio-temporal distribution of the disintegrated flakes 10 years after the fire and (b) to test the hypothesis that fires contribute to increased soil stoniness via physical and chemical flake erosion. The studied area included five lithostratigraphic units composed of chalk, limestone, and dolomite. The Schmidt Hammer test showed that after a decade, most of the spalled surface on the burned outcrops was lost, exposing new rock surfaces to atmospheric and weathering processes. The spalls and flakes were broken down and pulverized. The most prominent effects were changes in surface stoniness on the rendzina soils over the chalks, while there was less impact on the dolomite and limestone samples. The stoniness of the non-burned chalk was 23–39% and increased significantly to 69–86% in the burned area. Chalk erosion produced large (>16 mm, median 8–16 mm) and abundant gravel, suggesting fragmentation of large spalls, and particles that lost their bladed shapes becoming oblate and equant. While earlier works suggested that increasing rock fragment cover is often associated with the removal of fine particles, our results showed a substantial increase in rock fragments due to fire-induced exfoliation of rock surfaces, leading to long-term changes in soil properties. We therefore propose that the size, shape, and spatial distribution of rock fragments should be considered when examining the effects of rock fragments on hydrological and geomorphological processes or on post-fire soil rehabilitation.

Inland notches are elongated C-shape indentations carved into hard, dense carbonate rocks of the Mediterranean climate zone. In recent years these unique features became of particular interest as geoindicators of denudation and slope erosion processes. The study goals are to learn the processes acting upon the notches cavity by (1) examining the micromorphology of the backwall, (2) identifying and classifying zones of erosion, (3) learning the surface flow pattern and, (4) proposing an erosion mechanism induced by exfoliation. To this end, a machine learning algorithm was designed, using the microstructure, texture, streamlines formation and potential focal flow. The workflow uses data from terrestrial laser scanning, applies high-resolution textural and curvature analyses and trains an artificial neural network to the different segments of the notch. The reconstructed surface model shows division into three distinct belts within the cavity surface: (1) The spalled belt [SB]; (2) The transition zone belt [TZ] and (3) The deposition belt [DB]. Each belt owes its distinct microtopography, implying on different geomorphic processes. The newly developed methodology improves the recognition of streamline networks along the cavity backwall, which mimic alluvial networks. The organization of the reconstructed micro channels is similar to drainage basin systems, where, first order channels developed upstream converge into larger ones and diverge as distributaries as the gradient decreases, depositing tufa along the notches base.

Post-fire environmental footprint is expected at varying scales in space and in time and demands development of multi-scale monitoring approaches. In this paper, a spatially and temporally explicit multi-scale model that reveals the physical and morphological indicators affecting hillslope susceptibility at varying scales, is explained and demonstrated. The qualitative and quantitative suitability classification procedures are adapted to translate the large-scale space-borne data supplied by satellite systems (Landsat OLS8 and Sentinel 2 and 3) to local scale produced by a regional airborne survey performed by unmanned aerial vehicle (UAV). At the smallest spatial and temporal resolution, a daily airborne imagery collection by UAV is linked to micro-topography model, using statistical and mathematical approaches.

Inland notches are defined herein as horizontal “C”-shaped indentations, developed on the carbonate slopes or cliffs in the Mediterranean to semi-arid zones. The notches are shaped like half tubes that extend over tens or hundreds of meters along the stream valley slopes. In Mt. Carmel, a series of 127 notches have been mapped. On average, their height and width are 2–2.5 m but they can reach 6 m in height and 9.5 m in width. The geomorphic processes that create a notch combine chemical, mechanical, and biogenic weathering, which act together to generate initial dissolution and later flake weathering (exfoliation) of the bed, forming the notch cavity. We propose an epikarstic-subaerial mechanism for the formation and evolution of the notches. The notches are unique landforms originating from the dissolution and disintegration of the rock under subaerial conditions, by differential weathering of beds with different petrographic properties. The notches follow specific beds that enable their formation and are destroyed by the collapse of the upper bed. The formation and destruction alternate in cyclical episodes and therefore, the notches are local phenomena that vary over time and space.

A series of 31 short, parallel, steep channels, mostly of first or second order, occur at intervals of 300-500 m along 16 km of the western margin of the northern Dead Sea Rift (Israel). The analysis of tectonic and geometric activity along the marginal faults between the various segments is based on morphometric parameters, such as sinuosity of the mountain front, channel gradients, drainage basin elongation ratio, planimetric ratio, facet areas, hypsometric curves, and integrals. Longitudinal profiles of the channels were studied in relation to the underlying lithology and the presence of marginal faults. Despite the great differences in climatic and geomorphologic settings, comparison with other studies worldwide showed morphometric values similar to other tectonically active regions. The southern segments of the study area, which face the Hula deep depression, indicate enhanced geomorphic and tectonic activity. The northern segment proved dissimilar to the others, and is explained by its different tectonic setting. Six sedimentary, fan-like units composed of polymictic conglomerates were deposited along the mountain piedmont at the channel mouths. The units were dated by OSL, K-Ar, and archaeology to

[1] Fluid microinclusions in stalagmites have provided samples of paleowaters present during the growth of the stalagmite, but only in microliter amounts. Genty et al. (2002) discovered much larger water-filled macroinclusions in some stalagmites. Using computerized tomographic (CT) X-ray-scanning and magnetic resonance imaging (MRI) we searched for such macroinclusions in 21 stalagmites from diverse localities in North and Central America and the Caribbean. We show that most stalagmites contained numerous mm to cm-sized internal cavities (macroholes). These do not penetrate the outer surfaces which in most cases are deceptively unblemished. Some stalagmites have up to 10% average internal porosity. Two types of macroholes are distinguishable: axial holes formed during growth due to slower calcite accumulation at the axial drip site; off-axis holesformed penecontemporaneously with growth in discrete layers; these cut previous growth laminae showing that they are post-depositional. Using MRI on uncut, apparently sealed specimens, we find that very few of these cavities contain significant quantities of water although they were clearly formed while the stalagmite was being continuously bathed by drip water. Presumably, the water has escaped post-depositionally, through micro fissures, extensive connected hole system, crystal boundaries or other defects.

Massive destruction of carbonate rocks occurred on the slopes of Mount Carmel during the severe wildfire in 2010. The bedrock surfaces exhibited extensive exfoliation into flakes and spalls covering up to 80–100% of the exposed rocks; detached boulders were totally fractured or disintegrated. The fire affected six carbonate units – various types of chalk, limestone and dolomite. The burned flakes show a consistent tendency towards flatness, in all lithologies. The extent of the physical disruption depends on rock composition: the most severe response was found in the chalk formations covered by calcrete (Nari crusts). These rocks reacted by extreme exfoliation, at an average depth of 7.7 to 9.6 cm and a maximum depth of 20 cm. Scorched and blackened faces under the upper layer of spalls provide strong evidence that chalk breakdown took place at an early stage of the fire. It is possible to explain the extreme response of the chalks by the laminar structure of the Nari, which served as planes of weakness for the rock destruction. Three years after the fire, the rocks continue to exfoliate and break down internally. As the harder surface of the Nari deteriorates, the more brittle underlying chalk is exposed to erosion.