Search

Abstract: This study deals with the stripping of regolith on a steep slope by surface wash and shallow landslides and a deep-seated landslide at a lower slope that took place on 17 February 2003 at the village of Mazılık, east of Çanakkale, Turkey. Soil loss and shallow slides dominate on the deforested steep slopes in the study area and occur preferentially along slope-parallel sub-horizontal joint planes with clay coatings, particularly oxyhydroxides that are rich in Fe but poor in Mn as a result of weathering under well-drained conditions. Gully erosion also occurs where the regolith cover is relatively thick (up to ~4m). The area of the deep-seated landslide, however, is dominated by silty clay (46%). A geoelectrical resistivity survey revealed a clay-rich zone at depths of ~3–10m, corresponding to the slip surface of the slide, which was associated with excessive water content after the snowy day of 14 February 2003 with a daily precipitation of ~16.4mm. Based on Thornthwaite's water budget analysis, the study area has a slide-prone condition with excess soil-moisture content, heavy rainfall events, snow accumulation and snow melting in winter months, and low soil permeability also favouring slope instability. [Copyright &y& Elsevier]

This experiment was conducted to evaluate the effects of irrigation regimes and three types of plastic mulches on the land productivity, irrigation water use efficiency (IWUE), leaf area index (LAI), growth parameters (crown number, crown diameter and dry matter) and quality of drip-irrigated strawberries. It was conducted on cv. Fortuna strawberries grown in a high tunnel during the 2016–2017 growth season in the Eastern Mediterranean region of Turkey using a split-plot design with four replicates. The treatments comprised full irrigation (Ir100) and deficit irrigation (Ir50) in combination with three mulches, namely silver on black (S), black (B) and transparent (T) and no mulch (N). A higher soil moisture content was found under the S mulch, followed by B, T and N, throughout the entire crop growth period for both irrigation regimes. The greatest land productivity was obtained from the SIr100 (71.9 t ha−1) application, followed by BIr100 (59.4 t ha−1), TIr100 (52.1 t ha−1) and NIr100 (51.5 t ha−1). The IWUE, LAI and growth parameters reflected the same trend as the land productivity, which could be attributed to the soil water content of the mulches. Under the Ir50 irrigation regime, all of the parameters were significantly decreased, except for the IWUE. Furthermore, in spite of the extensive use of B mulch in Turkey's Mediterranean region, the performance of S mulch was mostly superior in terms of the accumulation of the selected polyphenols in the Fortuna cultivar. The highest ellagic, p-coumaric and syringic acids and relatively higher ascorbic, gallic and caffeic acids were obtained in the plants grown in the Ir50 plot and covered by the S mulch. Consequently, this study shows that the use of the SIr100 application can play a definite role in increasing the productivity of growing strawberries in a high tunnel in the Mediterranean environment. • Higher soil moisture content was determined using the Silver on black mulch during growing season. • LAI and plant growth parameters of Fortuna strawberry significantly influenced by the irrigation regimes and mulching colors. • The full irrigation and the silver on black polyethylene mulch increase the IWUE, land productivity. • Silver on black mulch, mostly showed better performance for the accumulation of the polyphenols in the Fortuna cultivar. [ABSTRACT FROM AUTHOR]

The growth and quality of licorice depend on various environmental factors, including the local climate and soil properties; therefore, its cultivation is often unsuccessful. The current study investigated the key factors that affect the contents of bioactive compounds of Glycyrrhiza glabra L. root and estimated suitable growth zones from collection sites in the Hatay region of Turkey. The contents of three bioactive compounds (glycyrrhizic acid, glabridin, and liquiritin), soil factors (pH, soil bearing capacity, and moisture content), and geographical information (slope, aspect, curvature, elevation, and hillshade) were measured. Meteorological data (temperature and precipitation) were also obtained. An analysis of variance (ANOVA) and multivariate analysis of variance (MANOVA) were performed on the data. The soil bearing capacity, moisture content, slope, aspect, curvature, and elevation of the study area showed statistically significant effects on the glycyrrhizic acid and liquiritin contents. A habitat suitability zone map was generated using a GIS-based frequency ratio (FR) model with spatial correlations to the soil, topographical, and meteorological data. The final map categorized the study area into four zones: very high (15.14%), high (31.50%), moderate (40.25%), and low suitability (13.11%). High suitability zones are recommended for further investigation and future cultivation of G. glabra. [ABSTRACT FROM AUTHOR]