Semi-arid Mediterranean Region Research Articles

Long-term restoration with organic amendments is clearer evidenced by soil organic matter composition than by changes in microbial taxonomy and functionality

Here, a degraded soil, located in a semi-arid Mediterranean region, was characterized 17 years after organic amendment with sludge or compost (differing in their stabilization degree) for restoration purposes. To do this, (i) soil physicochemical properties and plant cover, (ii) soil organic matter (SOM) content and composition, (iii) soil basal respiration and enzymatic activities, and (iv) abundance, taxonomic composition, and functionality (shotgun metagenomics) of microbial communities were studied. Increased SOM and nutrient contents were found in soil from amended plots with respect to the control, with no differences between amendment types. This is explained by the lasting effects of organic amendments and the higher plant cover. Thermal and pyrolytic analyses showed that the restoration process enriched soil mainly with SOM of intermediate recalcitrance and of high chemical diversity. SOM composition did not differ between amendment types. Increased microbial abundances and activities were found in the amended plots, without differences between compost and sludge. Shotgun metagenomics showed that microbial communities changed in taxonomic and functional terms between amended and unamended plots, but these differences were rather limited. The taxonomic differences between treatments were mainly driven by increasing abundances of Actinobacteria and decreasing abundances of Proteobacteria in soil from amended plots. Soil microbial communities in amended plots showed some functional adaptation to the increased nutrient contents and predominant nutrients forms. This, together with the higher microbial abundances detected, explained the conspicuous soil enzymatic activities reported in amended plots. The effectiveness of the studied soil restoration process was confirmed here from an integrative perspective.

Wintering raptor species distribution in a semiarid Mediterranean region: the relevance of lowlands and open habitats as stopover sites

As land-use cover types affect wintering birds’ strategies, studying their habitat suitability for species conservation is relevant. Predictive spatial models are considered excellent tools for conservation planning and improving our understanding of species distribution. Here we build models to predict the spatial distribution of raptor species that overwinter in SE Spain. We modelled the wintering raptor species distribution based on the presence-only data obtained between 2017 and 2019 and analysed their habitat preferences based on elevation and land-use cover variables. Our results show that altitude and distance to the coastline are the most important environmental factors to affect most species’ habitat suitability. Habitat type-related factors are other important predictors, and raptors subject of this study prefer lowlands and areas close to the coastline for overwintering by selecting open habitats, which include wetlands and irrigated and rainfed crops. This study highlights the importance of the habitat heterogeneity generated by wetlands and herbaceous crops within a low-altitude range as the optimal environment for wintering raptors. Such information should be considered for raptor conservation planning in human-altered landscapes.

Toward a Redefinition of Agricultural Drought Periods—A Case Study in a Mediterranean Semi-Arid Region

Drought is a powerful natural hazard that has significant effects on ecosystems amid the constant threats posed by climate change. This study investigates agricultural drought in a semi-arid Mediterranean basin through the interconnections among four indices: precipitation (meteorological reanalysis), vegetation development, thermal stress, and soil water deficit (remote sensing observations). While drought seems to be a clear concept with effective assessment tools (e.g., SPI and SPEI), the definition of drought periods is blurrier. This article examines the main drivers of agricultural drought, precipitation, soil moisture deficit, incipient vegetation development, and rising soil surface temperature. Their temporal connections in various agrosystems of the basin and the determination of drought periods by revisiting the run theory were investigated. The Pearson correlations at different spatial scales showed a medium to low level of agreement between the indices, which was explained by the geographical heterogeneity and the climatic variability between the agrosystems within the basin. It was also shown that the cascade of impacts expected from lower precipitations was revealed by the cross-correlation analysis. The connection between precipitation deficit and vegetation remains significant for at least one month for most pairs of indices, especially during drought events, suggesting that agricultural drought spells can be connected in time through the three or four selected indices. Short-, mid-, and long-term impacts of precipitation deficiencies on soil moisture, vegetation, and temperature were revealed. As expected, the more instantaneous variables of soil moisture and surface temperature showed no lag with precipitation. Vegetation anomalies at the monthly time step showed a two-month lag with a preceding effect of vegetation to precipitation. Finally, the determination of drought events and stages with varying thresholds on the run theory showed large variability in duration, magnitude, and intensity according to the choice of both normality and dryness thresholds.

The potential of young vegetative quinoa (Chenopodium quinoa) as a new sustainable protein-rich winter leafy crop under Mediterranean climate

The demand for protein products has significantly risen in the last few years. In western countries, animals are the primary source of protein; however, plants could take a share of this market due to lower production costs, among other advantages such as a lower environmental footprint. Quinoa (Chenopodium quinoa Willd.) is a well-known but under-utilized protein-rich crop, commonly cultivated for grain production. These plants were recently evaluated for their use as a non-traditional, green leafy crop. Here we assessed the potential of young vegetative quinoa as a new sustainable winter leafy crop in Israel—serving as a model for Mediterranean semi-arid regions, by evaluating yield, protein content and quality. Five quinoa accessions were sown on three winter sowing dates over two consecutive years. Plants were harvested when they reached 10% dry matter (DM). DM yield ranged between 574 and 1,982 kg ha-1 and was generally higher in the second year. Protein content ranged from 14.4–34% and was generally higher in the first year. Protein yield ranged from 111–471 kg ha-1 and was greatest on the December sowing date. DM and protein yields were positively correlated with plant density. Protein content was negatively correlated with plant density and DM yield. Our findings show that 200 g DM of young vegetative quinoa can meet the protein and most essential amino acid requirements for a 70 kg human adult. Prospects for cultivating young vegetative quinoa in Mediterranean countries as a new sustainable, protein-rich winter leafy crop are therefore high, as supported by its high protein yields and quality, and its requirement for only scant irrigation. Further studies should examine economic and other agrotechnical parameters toward the geographical distribution and expansion of young vegetative quinoa cultivation.

Evaluating temporal turnover in avian species richness in a Mediterranean semiarid region: Different responses to elevation and forest cover

AbstractAimWhen studying the effects of global change on biodiversity, it is far more common for the effects of climate change and land‐use changes to be assessed separately rather than jointly. However, the effects of land‐use changes in recent decades on species richness in areas affected by climate change have been less studied. We assess the temporal turnover in species richness of an avian community between a historical period and a modern one as a consequence of global change.LocationSemiarid Mediterranean ecosystem (southeastern Spain).MethodWe fitted a hierarchical multispecies occupancy model for each period (1991–1992, and 2012–2017), obtaining avian species‐specific estimates of occupancy probability in relation to environmental covariates (elevation and forest cover). We analyse the relationships between changes in the bird community and environmental variables, analysing the temporal turnover of the species richness and the richness‐based species‐exchange ratio.ResultsThe estimated species richness accounting for detectability was higher than observed species richness, and decreased in the more recent period. Following our hypotheses, we observed a dual pattern of species richness increase associated with different elevations, showing different species turnover rates due to the joint effects of climate change and land‐use change. There is a trend towards greater species richness with higher elevations that is associated with climate change, where the species turnover rate is low. Also, species richness increased towards lower elevations, but with a high turnover rate. The latter can be due to species expansions throughout new habitat configurations in bordering forest systems associated with anthropic land‐use changes.ConclusionsOur study is of great interest to understand the temporal turnover of avian species richness associated with areas experiencing both climate and land‐use change.

Carbonate morphological features of vineyard soils in a semiarid Mediterranean environment

AbstractMany vineyard soils in semiarid Mediterranean environments develop from carbonated materials and often show very diverse forms of pedogenic calcium carbonate accumulations. Based on 275 vineyard soil profiles in the Castilla La Mancha (CLM) territory (Spain), this paper presents an in‐depth comprehensive study of a large number of morphological expressions of these carbonate distributions, while exploring various pedogenesis formation hypotheses. The interactions among the calcareous nature of parent material, surface topography and climate are the factors that most affected their morphology and pedogenesis. The occurrence and distribution of carbonate features in CLM vineyard soils can be more complex than in other areas. Many accumulations are relatively ancient, which is the case of petrocalcic horizons, and in‐keeping with conservative means, which reveals the occurrence of successive carbonate accumulation cycles. More recently dissolved and precipitated seasonally pedogenic carbonates (sometimes as coatings) have appeared, which are nothing more than a simple recent redistribution of carbonates. A structural imprint is observed: pedogenic carbonates appeared much more abundantly on the lowermost horizons, which can be related to the repeated redistribution phases that occurred in different pedogenesis stages. The data provided herein help to improve the understanding of the nature of viticultural calcareous soils in semiarid Mediterranean regions.

Weed seed bank dynamics during a three year crop rotation in Mediterranean semi-arid region (Northwestern Algeria)

Weed seed bank dynamics during a three year crop rotation in Mediterranean semi-arid region (Northwestern Algeria)

Water Management Adaptation to Climate Change in Mediterranean Semiarid Regions by Desalination and Photovoltaic Solar Energy, Spain

Integration of renewable energy sources and water production technologies is a must when facing water scarcity problems in semiarid regions, such as Mediterranean regions. The use of additional water resources and production methods, such as reclaimed water and, more specifically, desalinated water, means present and necessary water resources to introduce in the water balances to attend to water demands within a global warming and droughting scenario. These solutions have the inconvenience of energy/power needs and costs. However, the development of renewable energies like photovoltaic solar energy, with lower and lower costs and greater efficiency, makes these economically feasible facilities, reaching competitive production costs for marine or sea desalinated water by around 50% of reduction in energy costs and 20–30% of savings in final water production cost. This paper presents a practical project or action focused on the integration of renewable energies and new water resources by introducing a Photovoltaic Energy Plant (PVEP) as an energy source to feed a Seawater Desalination Treatment Plant (SWDTP). The PV facility is designed to cover all the energy demanded using the SWDTP during the day, and even studying the possibility of selling the energy production exceeds and injecting them into the energy supply network, covering the needs of buying energy needed during the high period where there is no photovoltaic energy production. Thus, savings related to energy costs and even incomes coming from energy sales mean an important reduction in operation costs or expenditures (OPEX), which makes economically feasible and sustainable the investment and the final price of water produced within the Mutxamel SWDTP. The final reduction cost in water desalination reaches 25% on average.

Impacts of a hydroinfiltrator rainwater harvesting system on soil moisture regime and groundwater distribution for olive groves in semi-arid Mediterranean regions

Dry periods in semi-arid regions constitute one of the greatest hazardous features that agriculture faces. This study investigates the effects of using a new device called ‘Hydroinfiltrator Rainwater Harvesting System (HRHS) on the water balance of soils. It was designed for arid and semi-arid zones affected by long periods of drought punctuated by heavy rainstorms. The new hydroinfiltrator consists of a net-like shell filled mainly with biochar. It is cylindrical in shape, is placed vertically and is half-buried in the soil around the crop tree to facilitate the infiltration of rainwater, irrigation or runoff water deep into the soil. The experimental plot is located in Baena (Córdoba, southern Spain) in an olive grove where the hydroinfiltrator was installed in 90 olive trees while 10 were left as a control group. In the xeric climate (bordering on arid), typical of the region, soils without a hydroinfiltrator have had a low infiltration rate, which reduces the effectiveness of precipitation and significantly increases the risk of water erosion. The effects of infiltration assisted by the device were analysed by simulating a torrential rain in which 600 L of water were passed through the hydroinfiltrator on an olive tree which had been installed 3 years previously. Geophysical methods (electrical resistivity tomography, ERT), direct analyses of soil samples, both in situ and in the laboratory, and theoretical flow models indicated a very significant increase in soil moisture (which nearly tripled in respect to the control group) because water was absorbed into the soil quickly, preventing runoff and water erosion. The soil moisture at 20 cm depth was 2.97 times higher with the HRHS than in the control plots. In addition, olive production increased by 211% and was higher in fat yield by 177%. Moreover, the resistivity profiles, taken by ERT showed that the water that entered the soil accumulated in the root zone of the olive tree, encouraged by the preferential pathways created by the roots and away from the surface, which prevented rapid evaporation during the high temperatures of spring and summer. Here we show for the first time that the use of the hydroinfiltrator rainwater harvesting system represents a significant improvement in the use of scarce water resources caused by climate change, providing agronomic and environmental benefits for rainfed, Mediterranean agricultural systems.

Medium-Term Effects of Sprinkler Irrigation Combined with a Single Compost Application on Water and Rice Productivity and Food Safety.

Traditional rice (Oryza sativa L.) management (tillage and flooding) is unsustainable due to soil degradation and the large amount of irrigation water used, an issue which is exacerbated in the Mediterranean region. Therefore, there is a need to explore rice management strategies in order to improve water-use efficiency and ensure its sustainability. Thus, field experiments were conducted to determine the medium-term effects of different irrigation and tillage methods combined with a single compost application on water and rice productivity, as well as food safety in a semiarid Mediterranean region. The management systems evaluated were: sprinkler irrigation in combination with no-tillage (SNT), sprinkler irrigation in combination with conventional tillage (ST), which were implemented in 2015, and flooding irrigation in combination with conventional tillage (FT), and their homologues (SNT-C, ST-C, and FT-C) with single compost application in 2015. In reference to rice grain yield, the highest values were observed under ST treatment with 10 307 and 11 625 kg ha-1 in 2018 and 2019 respectively; whereas between FT and SNT there were no significant differences, with 8 140 kg ha-1 as mean value through the study. Nevertheless, sprinkler irrigation allowed saving 55% of the total amount of water applied in reference to flooding irrigation. Furthermore, the highest arsenic concentration in grains was found under FT but it decreased with compost application (FT-C) and especially with sprinkler irrigation, regardless of tillage management systems. However, sprinkler irrigation favors the cadmium uptake by plants, although this process was reduced under SNT in reference to ST, and especially under amended compost treatments. Therefore, our results suggested that a combination of sprinkler irrigation and compost application, regardless of the tillage system, could be an excellent strategy for rice management for the Mediterranean environment in terms of water and crop productivity as well as food safety.

Geophysical assessment for deep structuring mapping and water resources perspectivity in semi-arid land region (northeastern Tunisia, Mediterranean Basin)

In Mediterranean semi-arid regions, shallow aquifers are generally over-exploited. However, several deeper groundwater boreholes exhibit serious problems of low hydraulic yield and dry wells. The existence of reliable information about the regional geological structure can enhance the success of deep well programmes. Geophysics has proved very useful as a fast and efficient tool to understand the structuring of deep hydrogeology aquifers. Indeed, the identification and characterization of the deep structures of the Bir Drassen–Sidi Toumi region (Cap-Bon, northeastern Tunisia) contribute to a better quantification of the groundwater potential, allowing more sustainable management. This province can be considered as the SW extension of the NE–SW Jebel Abderrahman Atlasic anticline, one of the most prominent geological structures in northeastern Tunisia. To identify the Miocene and Oligocene reservoirs, a geophysical study was carried out using advanced gravity analysis, supported by boreholes, and seismic and geoelectrical calibration. Different gravity filters were applied to reveal the sub-basin architecture and faulting network in the region. By calculating the maxima of the total horizontal gravity derivative and the distribution solutions for Euler's equations, a set of deep faults of different directions was divulged. Time-domain electromagnetic mapping illustrated the influence of these fault zones on the regional arrangement of sub-basin aquifers and their recharge processes. Finally, a 3D residual gravity inversion was carried out to better image the tectonically controlled depocentres associated with prolific thick fluvial–deltaic reservoirs. These ‘deep aquifer valley’ can be suggested as strategic targets for deep hydrogeological exploration planning.

Comparative Study of Different Crassulaceae Species for Their Potential Use as Plant Covers to Improve Thermal Performance of Green Roofs

The presence of green roofs in urban areas improves the energy efficiency of buildings; contributes to the capture of CO2, decreasing pollution; and improves the appearance of cities, increasing their sustainability. Additionally, green roofs must include plant species with low requirements and maintenance, and thus, succulent species could be useful in Mediterranean semi-arid regions. In this work, the thermal inertia and the effect of different succulent species as thermal barriers on mitigating the increase in temperature inside experimental compartments were studied in comparison to conventional covers used in the Spanish Mediterranean for a whole year. In general, green covers were more efficient than conventional ones for controlling temperature. Thus, temperatures under green covers were up to 8 °C lower than conventional covers and 3–5 °C lower than the ambient temperature at noon on summer days. Furthermore, significant differences were found between green covers. Thus, despite having high thermal inertia, Aptenia cordifolia showed the worst temperature records, while Aeonium arboreum was the most efficient at mitigating temperature changes both on cold winter nights and hot summer days—even better than Sedum spp., a usual succulent used commercially. Our results demonstrate that succulent species are efficient materials to use as green covers to improve thermal conditions in buildings in Mediterranean cities. This also suggests that the mixture of succulent species (i.e., not only made of Sedum spp.) with different colors and textures could beautify green roofs without compromising their energy efficiency.

Geospatial Multi-Criteria Approach for Ranking Suitable Shallow Aquifers for the Implementation of an On-Farm Solar-PV Desalination System for Sustainable Agriculture

The main purpose of this study was to assess and rank suitable shallow aquifers for the implementation of a solar-PV desalination system (SmaIrriCube) in small-scale farms in arid and semi-arid Mediterranean regions, such as Tunisia. A GIS-based Multi-Criteria Decision Analysis (MCDA-GIS) model was developed. A SMART method was applied to evaluate the relative importance of the criteria and the Weighted Sum Model was used to generate the suitability map, in line with technology efficiency (SmaIrriCubeEff) and farmer acceptability (SmaIrriCubeAcc). The overall results showed that 188 out of the 204 Tunisian shallow aquifers are potentially viable for implementing the SmaIrriCube system. For SmaIrriCubeEff, the central and southern aquifers were found to be the most suitable, with a Suitability index (Si) exceeding 0.5, mostly due to the high solar irradiation and evaporation rate. In terms of acceptability, the southern aquifers are the most preferable, with a Si higher than 0.56, due to high solar irradiation, evaporation rate and groundwater quantity and quality. The results also indicated that the removal of evaporation and solar photovoltaic modules significantly affected the aquifer ranking, with the southern and central aquifers being the most sensitive to these criteria. The GIS-MCDA approach was proven to be a practical, upgradable and time/cost-efficient solution for decision-making, which can be extended to other technologies and/or regions with similar climatic characteristics.

Assessment of surface water quality in a semi-arid Mediterranean region. Case study of Sikkak dam (north-western Algeria)

AbstractAs far as industry, agriculture, urbanization, lithology and climate are concerned, surface-water vulnerability to pollution has not ceased to amplify especially in semi-arid to arid areas. In the countries of the southern shore of the Mediterranean and most particularly in Algeria, surface-water quality is highly impacted by anthropogenic activities and climate change. It thus requires a complete diagnosis of the evolution of these impacts through a survey. The present study aims at characterizing and assessing the temporal evolution of surface-water quality in Sikkak wadi watershed (north-western Algeria), particularly at the Sikkak dam. The methodology that was applied to assess and interpret monthly surface-water quality results gathered throughout an 11-year period of time survey (2005−2015) included the following: a quality-grading method, a trend-following approach, a seasonal analysis as well as a principal components analysis (PCA). The results analyzed according to the classification of the Algerian National Agency for Water Resources (ANRH) revealed that the Sikkak dam water is characterized by a natural mineralization that is good (61.37%) to medium (38.63%) taking into account electrical conductivity (EC), chloride, sodium, calcium, magnesium and sulfate contents. However, it is found to be highly contaminated by organic pollution ranging from bad grade (46.37%) to fairly medium quality (34.98%). COD, BOD, nitrate, nitrite, ammonium and orthophosphate were used as the evaluation parameters. In general and taking into account all the parameters of pollution, the ‘medium’ and ‘good’ classes dominate the quality of the surface water of the Sikkak dam with a percentage of 40.37% and 37.28% successively, followed by the ‘poor’ (20.72%) and ‘very poor’ (1.63%) classes. The trend-following method shows that the surveyed waters moderately tend towards more alkaline and exhibit increasing COD and chloride. Further, the waters show a decreasing EC, BOD5, organic matter, nitrogen and phosphate as well as most of the salinizing and carbonating compounds. This is mainly due to the contribution of wastewater treatment plant in improving the water quality. The PCA confirmed that the different forms of pollution (domestic, industrial, agricultural) and salinization (for 56.77%) are the main factors for the degradation of the quality of the dam water.

Long Term Effects of Tillage–Crop Rotation Interaction on Soil Organic Carbon Pools and Microbial Activity on Wheat-Based System in Mediterranean Semi-Arid Region

Conservation agriculture based on no-tillage (NT) and crop rotation allows to enhance soil health. Based on data collected from long-term trials in a semi-arid region of Tunisia, results showed that NT increased significantly soil organic carbon stock (SOCS), soil microbial biomass carbon (SMBC), arbuscular mycorrhizal fungal (AMF) root colonization, and soil microbial respiration (CO2) at 0–20 cm topsoil layer compared to conventional tillage (CT). Moreover, triennial rotation (TRI), based on annual succession of Faba bean-Durum wheat-Barley, and biennial rotation (BI), based on annual succession of Faba bean-Durum wheat, increased significatively SMBC, AMF, and CO2. Likewise, a significant benefit of the two-way interactions Tillage × Rotation was observed. Furthermore, NT combined with TRI recorded the highest SOCS (2181 g C m−2), SMBC (515 mg C kg−1 soil), AMF (14%), and CO2 which is an indicator of soil microbial respiration (1071 mg CO2 kg−1 soil). The current results highlight the benefit adoption of minimum or (NT)combined with crop diversification on soil health.

Correction: Piscitelli et al. Adaptive Agricultural Strategies for Facing Water Deficit in Sweet Maize Production: A Case Study of a Semi-Arid Mediterranean Region. Water 2021, 13, 3285

There was an error in the original publication [...]

Irrigation management or climate change ? Which is more important to cope with water shortage in the production of table grape in a Mediterranean context

Table grape production requires large amount of water, which can be problematic in semi-arid Mediterranean regions, where climate change projections anticipated reductions in water availability associated to decreases in precipitation and increases in temperature. In this context, this study aims to evaluate the effect of contrasting irrigation strategies and climate change scenarios on key water balance variables using a Chilean Table grape crop as case study. A standard and an improved irrigation management treatments were implemented in situ during the 2015/2016 and the 2016/2017–2017/2018 observed growing seasons, respectively. Then, the HYDRUS-1D water transfer model was run to simulate the three observed growing seasons and 27 near future growing seasons (2019/2020–2044/2015) under climate change conditions. Satisfactory calibration and validation results against soil moisture and water storage measurements were obtained within the first and the second observed growing seasons respectively (RRMSE values below 5%). Results during the observed seasons showed that by changing the standard irrigation by the improved irrigation management, the water use efficiency (WUEi) increases from 49.5% to 55.7%. For the near future, the calibrated model shows that under all the tested climate change scenarios, irrigation strategies based on supplying 80% and 50% of the crop evapotranspiration (ETc) (deficit irrigation scenarios) have larger efficiencies compared to the standard irrigation management (presenting a higher actual basal crop coefficient and lower percolation). Similar results were obtained under future extreme climate change years, defined as the ratio between model-based projections of reference evapotranspiration (ET0) and precipitation, with the deficit irrigation scenarios having larger efficiencies than the standard irrigation management. Based on these results, it is concluded that by mid- century, the irrigation management has more relevance than climate change impacts for tables grapes growing under a Mediterranean climate in central Chile.

Chemical and in vitro evaluation of Leucaena (Leucaena leucocephala) Leaves as a Substitute of Alfalfa (Medicago sativa L.) with/without Rejected Green Banana Fruits (Musa paradisiaca)

Leucaena leaves and rejected green banana fruits can be promising to cope with feed gaps in arid and semi-arid Mediterranean regions. The present study evaluated the feeding value and secondary active compounds of Leucaena leaves and rejected green banana fruits for ruminants using a semi-automated gas production (GP) system. Comparisons were made with the traditional feeds as alfalfa, and Dichanthium spp. grass hay. Analysis of HPLC was performed for the feed ingredients to characterize the main phenolic components. The in vitro evaluation was carried out for the experimental feed ingredients and diets. Four diets were formulated as the first diet consisted of alfalfa and grass hay at a ratio of 35:65 (AG), the second diet composed of alfalfa, grass hay, and green banana fruits at a ratio of 35:55:10 (AGB), third and fourth diets were prepared by replacing alfalfa in AG and AGB with Leucaena leaves to be LG and LGB, respectively. Leucaena leaves showed a high content of valuable phenolic components that have antioxidant and anti-inflammatory properties, such as gallic acid, ellagic acid, and naringenin. Moreover, Leucaena leaves and diet had higher crude protein, total phenols, and total tannins than alfalfa, which was reflected on the chemical composition of diets, and recorded the lowest total accumulative GP at 24 hours leading to low CH4 and CO2 production. Banana fruits recorded the lowest ruminal pH, ammonia concentration, and degraded neutral detergent fiber, compared to other feed ingredients, while it had the highest GP and degraded organic matter. Therefore, it is highly recommended to use Leucaena leaves in animals’ diets with/without rejected green banana fruits as an alternative feed resource with potential environmental and animal health benefits.

Energy and Water Related Parameters in Tomato and Cucumber Greenhouse Crops in Semiarid Mediterranean Regions. A Review, Part II: Irrigation and Fertigation

Increasing agricultural systems’ resource efficiency is the key action for producing adequate food quantities in semi-arid Mediterranean regions while coping with water scarcity, environmental constraints and economic issues. Optimisation of irrigation and fertigation practices imposes different approaches, considering plant-water-soil relationships based on prevailing greenhouse microclimatic conditions, ensuring optimal production per drop of water and unit of fertiliser. In the content of "precision agricultural farming systems", nutrient uptake modelling, phyto-sensing, smart and sustainable technologies must be applied for monitoring and evaluating water and nutrients crops supply. However, in many cases, the use of irrigation and fertigation recipes given in the literature may not be compatible in the Mediterranean, as they usually originated based on northern European climatic conditions. The objective of this work is an attempt to understand various aspects of irrigation and fertigation management in vegetable fruiting crops such as tomato and cucumber towards nutrients and water resource sustainability in Mediterranean greenhouses.

Energy and Water Related Parameters in Tomato and Cucumber Greenhouse Crops in Semiarid Mediterranean Regions. A Review, Part I: Increasing Energy Efficiency

Countries located in the Mediterranean region share many common features in terms of agricultural sustainability and economic realities of modern farming, as they are affected by water scarcity, energy use and climate suitability. Greenhouses are considered as a mitigation measure to combat climate change and as a sustainable production system. The majority of greenhouses in the Mediterranean region are rudimentary, while those in Central and North Europe are characterized by equipment of a high technological level for greenhouse climate and fertigation management. However, the technological innovations and research originating from Central and North Europe glasshouses may not be appropriate for use in Mediterranean plastic greenhouses when considering the trade-off between agronomic needs and potential energy savings. Identifying energy measures suitable for the local climate will improve energy efficiency and crop performance toward the goal of greenhouse sustainability. This review mainly focuses on renewable and energy-efficient control systems in Mediterranean greenhouses, where crops such as tomato and cucumber are widely grown.