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Pesticides are used worldwide to support food security for the growing world population. In Israel thousands of tons of pesticides are applied every year and find their way to the entire catchment: soil, surface water, interflow and groundwater. In addition, the treated waste water applied for irrigation convey pharmaceuticals that are distributed in the catchments as well. Previous studies focused one or a few pollutants, which limit the scope of the chemical features on the pollutants fate. Other research focused a certain flowpaths: the stream and tributaries, or groundwater pollutants. This study provides a wide scope of the all 3 main flowpaths (surface water, interflow, groundwater) and the fate of over 70 pesticides in the field scale, including time series in short temporal resolution for groundwater and interflow.The study took place during irrigation (Apr 2021) and during winter 2022, focusing two winter storms (Jan 2022). The study fields border the Kishon, the 2nd largest coastal stream in Israel. Both fields have subsurface drainage system to address high water level and bad drainage soils. The subsurface drainage system provides direct approach to the subsurface water. Water collected from the pipe outlet of the system represent subsurface, but also from manholes, which are the approach to the subsurface system. Groundwater was collected from piezometers to deep and shallow aquifers in both fields, according to accepted protocol for ground water sampling, utilizing a metal bailor. Surface water was collected from field surface, applying RCU-Runoff Collector Units and also from secondary and primary surface drainage trenched in the field. All water were collected in glass bottles, and were analyzed by LC/MS.In this study the spatial distribution in the field scale was demonstrated, including the vertical direction. Samples that were collected from surface water, interflow and groundwater show the dominant flowpath of each compound, where the chemical characteristics were critical to obtain the compound pathway. For example, imidacloprid was applied only a few weeks before the storm and found in high concentration in surface water. Interflow water collected from subsurface drainage system show imidacloprid concentrations which are order of magnitude lower for the entire winter. On the other hand, diflufenican was applied more than two years ago was found in high concentration in surface water, as a result of low degradability and low mobility, yet subsurface concentrations were negligible. Both compounds were in high concentration near the application area (onion section of the field). Time series (interflow, groundwater) were key data, where taken before, during and after water enter soil column during irrigation or a rain event. All data clustering analysis, showing pairs of compounds vs each other was operated. A clear clustering, in most cases, fit the spatial distribution establishing 4 groups: 1. surface runoff from field and all trenches 2. Subsurface water pipe (and manholes in most cases) 3. Groundwater 4. StreamThis research provides a large data base, including temporal and spatial point of view which are innovative and provide a comprehensive scope for field-scale processes.

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.

Non-point pollutants, such as fertilizers and pesticides, are transported in water and travel via complex hydrologic flowpaths, with each field being a diffuse source of agrochemicals. Although pollutant transport in tile drains has been investigated widely, most studies occurred in temperate zones, with insufficient focus on leaching timing. We investigate the leachate timing and specific pathways from the field to the stream, to better understand the unique transport dynamics in Eastern Mediterranean climates, in areas with extensive subsurface drainage systems. To improve basin management strategies, this study targets the knowledge gap regarding specific pollutant transport and timing, which results in inefficient policies to reduce water pollution. In our investigation of two crop fields in the Kishon basin, Israel, the systems drain both soil water and high groundwater, providing an opportunity to examine water quality dynamics in multiple pathways. We collected water samples from field runoff, subsurface pipes, and groundwater during summer irrigation and winter storm events. Results show a clear spatial distribution of agrochemicals due to their properties. Higher number of pesticides were found in ponded field water and their concentrations were higher in order of magnitude in compare to tile drainage pipes. We identified pesticides in all samples that had not been applied to the field within the last 1.5 years. Leaching timing was demonstrated with higher pesticide concentration appearing in water collected from drainage pipes during irrigation and pesticides concentration decreasing after irrigation ended. The concentration changes were observed within 12-15 hours after opening or closing irrigation. Tracking the pools, the high concentration in the top soil creates a pesticides reservoir transported with the onset of irrigation and rain. The leaching timing was demonstrated as well by lab results and measuring in-situ EC and pH. After a four-day storm, EC declined drastically, demonstrating the input of relatively low nutrient content water to the high concentrations present in the high water table. Later in the winter, surface runoff in the main draining trench from the field to the stream contained high concentrations of phosphate and sediments and low concentrations of nitrate and chloride, compared to surface runoff in the field. Since nitrate and chloride are highly soluble, the reduced concentration in the draining trench to the stream demonstrates that water percolates downwards through the soil column with solutes rather than propagating with surface runoff, and particulate-bound species and sediments travel via surface runoff to the stream. Demonstrating pollutant transport pathways and timing, we provide a window into the propagation mechanisms of pollutants at a small scale, to support decision making and improve basin management.