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Thorough knowledge of soil lithology and its properties are of considerable importance to agriculture. These parameters have a direct impact on water permeability and the content of the water in soil, which represent significant factors in crop yield, decisively determining the design of irrigation systems and farming processes. In the framework of this study, and considering the inevitable impacts of climate change, the rational management of water resources and the optimization of irrigation through innovative technologies become of significant importance. Thus, we propose an interdisciplinary approach based on robust techniques from the allied fields of earth (geological mapping, geophysical methods) and soil sciences (sampling, mechanical analysis) assisted by statistics and GIS techniques. Clay or the sum of clay and silt soil content is successfully determined from the normalized chargeability using induced polarization and electrical resistivity techniques. Finally, we distinguished three classes (S1, S2 and S3) considering the clay or the sum of clay and silt soil content in the study area (a) based on the dry period geophysical data and (b) using as classification criterion the spatial distribution of the geological formations. [ABSTRACT FROM AUTHOR]

• Cultivation of Urospermum picroides under minimal irrigation and organic fertilization. • Integrated nutrient management (ΙΝΜ) fertilisation by foliar application. • Wild edible Mediterranean plant with medicinal and health-promoting properties. • Foliar semi-organic fertilization, alternative increases photosynthetic capacity. • Fertilization without compromising the nutritional profile of edible products. Urospermum picroides (L.) Scop. ex F. W. Schmidt (Asteraceae) is rich in secondary compounds, with antimicrobial and antioxidant activity, medicinal and health-promoting properties, however, like many other wild edible plants of the Mediterranean, it is still underutilised. This study focused on the pilot cultivation of U. picroides, under minimal irrigation and organic, integrated nutrient management (ΙΝΜ) fertilisation (by foliar application) in Crete, Greece, analysing its response in terms of yield characteristics and nutritional content. The foliar fertilisation treatments consisted of a control treatment (CO), a conventional water-soluble fertiliser (CV), a semi-organic nitrogen fertiliser (TR), a liquid semi-organic fertiliser (TF), and v) a mix of the conventional and semi-organic fertiliser (CF). Physiological characteristics (i.e., SPAD and Fv/Fm) were assessed during cultivation, while yield and leaf nutrient parameters were determined, at harvest. Treatments containing bioactive compounds (TF and CF) almost doubled the fresh and dry weight of U. picroides shoot compared to the control (CO) treatment (172% and 160%, respectively) which can be partially ascribed to the elevated physiological characteristics of the TF and CF fertilisation treatments. Even more, nitrogen rich treatments (CV and TR) improved yield characteristics compared to the control, but the effect was not as pronounced as that achieved by TF and CF semi-organic fertilization treatments. Our results indicate that the application of foliar semi-organic fertilization seems to be an effective alternative practice to increase photosynthetic capacity and concomitantly fresh and dry yield of U. picroides without compromising the nutritional profile of the edible product. [ABSTRACT FROM AUTHOR]

[Display omitted] • We offer insights on the perception of urban green (UG) in Mediterranean islands. • 88 % of the participants consider public UG necessity for their wellbeing. • Fewer (69 %) consider private UG equally necessary. • Despite their profound necessity, citizens consider existing public UG insufficient. • For urban use, main covariates are compiled into a public UG approval index. The objective benefits that humans derive from natural ecosystems and their enduring manifestation in urban green spaces (UGS) is well-know. Nevertheless, citizens' preference, and perceived necessity of UGS is not always evident and therefore often not accounted for, especially in the context of urban planning decisions, where it could positively influence the effectiveness of greening strategies. This information is especially important in the Mediterranean islands, due to their unique character. Here we address these aspects, including the way they are affected by UGS perceived adequacy, accessibility, maintenance, distance, and other self-reported obstacles using a questionnaire completed by 703 residents of the Island of Crete, Greece. To integrate results, main covariates are compiled into the newly developed public UGS approval index. Survey results show that, 87.82 % of the participants consider public UGS highly necessary for their wellbeing, while only 69.22 % consider private UGS equally necessary. Nevertheless, private UGS were the most frequently visited green at 16.3 ± 0.7 days/month. Public UGS is considered more necessary for female respondents, under 35 years, living in an apartment in the city. However, it emerged that despite the significantly higher need for public UGS in the urban centers of the island, residents consider UGS inadequate and often inaccessible for people with mobility problems. Integration of the results in the new approval index, shows that citizens of Crete, are on average neutral or disapprove of local public UGS. The outcomes can be used for targeted interventions at existing and strategic planning in new UGS. [ABSTRACT FROM AUTHOR]

Climate change is expected to have a significant impact on the hydrologic cycle, creating changes in freshwater resources. The Intergovernmental Panel on Climate Change (IPCC) predicts that, as a result, floods and prolonged droughts will take place at increasingly frequent periods. The Mediterranean has been described as one of the main climate change 'hot-spots', with recent simulations showing a collective picture of substantial drying and warming. This effect appears more pronounced during warm periods, when the seasonal decrease of precipitation can exceed control climatology by 25-30%. Despite the decreasing annual rainfall trend, an increase in the amount and intensity of wintertime rainfall is evident. However, the scientific question on the quantitative impact of these signals to small scale coastal watersheds and Mediterranean islands has not been answered. The state-of-the-art Ensembles dataset was employed to assess the impact of the changing climate on the water availability of the island of Crete at basin scale. Here, the Ensembles precipitation and temperature data is used as input for a rainfall-runoff model previous calibrated for the whole island with the principle of regionalization. Data analysis for the period 1970-2100 reveals an overall decreasing precipitation trend which, combined with a temperature rise, leads to substantial reduction of water availability. Quantitative results of hydrological change provide the data required to improve knowledge and adaptation policy to water shortages. [ABSTRACT FROM AUTHOR]

This paper explores methodologies for developing intelligent automated decision systems for complex processes that contain uncertainties, thus requiring computational intelligence. Irrigation decision support systems (IDSS) promise to increase water efficiency while sustaining crop yields. Here, we explored methodologies for developing intelligent IDSS that exploit statistical, measured, and simulated data. A simple and a fuzzy multicriteria approach as well as a Decision Tree based system were analyzed. The methodologies were applied in a sample of olive tree farms of Heraklion in the island of Crete, Greece, where water resources are scarce and crop management is generally empirical. The objective is to support decision for optimal financial profit through high yield while conserving water resources through optimal irrigation schemes under various (or uncertain) intrinsic and extrinsic conditions. Crop irrigation requirements are modelled using the FAO-56 equation. The results demonstrate that the decision support based on probabilistic and fuzzy approaches point to strategies with low amounts and careful distributed water irrigation strategies. The decision tree shows that decision can be optimized by examining coexisting factors. We conclude that irrigation-based decisions can be highly assisted by methods such as decision trees given the right choice of attributes while keeping focus on the financial balance between cost and revenue. [ABSTRACT FROM AUTHOR]

Summary: An assessment of the impact of global climate change on the water resources status of the island of Crete, for a range of 24 different scenarios of projected hydro-climatological regime is presented. Three “state of the art” Global Climate Models (GCMs) and an ensemble of Regional Climate Models (RCMs) under emission scenarios B1, A2 and A1B provide future precipitation (P) and temperature (T) estimates that are bias adjusted against observations. The ensemble of RCMs for the A1B scenario project a higher P reduction compared to GCMs projections under A2 and B1 scenarios. Among GCMs model results, the ECHAM model projects a higher P reduction compared to IPSL and CNCM. Water availability for the whole island at basin scale until 2100 is estimated using the SAC-SMA rainfall–runoff model And a set of demand and infrastructure scenarios are adopted to simulate potential water use. While predicted reduction of water availability under the B1 emission scenario can be handled with water demand stabilized at present values and full implementation of planned infrastructure, other scenarios require additional measures and a robust signal of water insufficiency is projected. Despite inherent uncertainties, the quantitative impact of the projected changes on water availability indicates that climate change plays an important role to water use and management in controlling future water status in a Mediterranean island like Crete. The results of the study reinforce the necessity to improve and update local water management planning and adaptation strategies in order to attain future water security. [Copyright &y& Elsevier]

Summary: The seasonality of the hydrometeorologic characteristics of floods that occurred in Crete during the period 1990–2007 is presented. Hydrological characteristics were analyzed using seasonality indices based on a dataset of 53 daily precipitation stations as well as 15 daily and 7 monthly recording flow stations. The atmospheric circulation conditions during the flood events were examined based on a joint subjective classification and meteorological analysis. The flood event-based seasonality was found to coincide with the seasonality of the daily precipitation maxima of November and December. The seasonality of the three largest long term daily precipitation maxima indicates that 50% of the maximum precipitation events occur from November to January (NDJ period). Analysis showed that the maximum annual stream flows in Crete are lagging by approximately 1month from annual maximum daily precipitation in the region. The circulation type classification of the flood events showed that most of the weather systems occurring in the Mediterranean and passing over Crete have SW, NW and W direction. For the majority of the events, a common mean sea level pressure gradient field was observed over Europe. This comparison of the seasonality of selected hydrometeorologic characteristics reveals valuable information within the context of flood occurrence. [ABSTRACT FROM AUTHOR]

The aim of this paper is the creation of an integrated and free-access web platform for parcel irrigation water management on a large spatial scale (Water District of Crete, in Greece) in order to: a) accurately determine the irrigation needs of the main crops for Crete such as olives, citrus, avocados and vineyards, b) design strategies, for optimal adaptation of the agricultural sector in the context of climate change, and c) incorporate the dynamic integration of the above information through the creation of a digital platform. In the proposed decision-making system, essential factors are taken into account, such as real-time meteorological data, information about the type and spatial distribution of the agricultural parcels in Crete, algorithms for calculation crop evapotranspiration per development stage and age of the crops, satellite remote sensing techniques in combination with field surveys to depict accurate soil texture map for the whole island of Crete as well as sustainable cultivation practices for saving water per crop and parcel geomorphology. Based on the proposed decision-making system, users will have the opportunity in any specific location/farm in Crete to know the irrigation needs of the crops in real-time and obtain information about proper climate-water adaptation practices. The main novelty points of the proposed platform include the derivation of parcel-level soil texture data from Sentinel-2 satellite imagery and field samples, the comprehensiveness of the irrigation management information, the relatively low data requirements and the application interface simplicity provided to the end-user., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)