Adaptations in irrigated agriculture in the Mediterranean region:an overview and spatial analysis of implemented strategies

In order to meet future food demand while sustainably managing available land and water resources, irrigated agriculture in semi-arid regions needs to adapt as a response to climate and socio-economic change. In this study, we focus on the Mediterranean region, a dynamic region, which is highly dependent on irrigated agriculture. We provide insight on adaptation strategies implemented on farm level, by doing a systematic review of studies in the region. Our analysis reports 286 implemented adaptations, on 124 different locations throughout the Mediterranean. Additionally, 142 drivers and 324 effects of adaptations were noted. We identified 31 adaptation strategies in 5 main categories: (1) water management, (2) sustainable resource management, (3) technological developments, (4) farm production practices, and (5) farm management. Strategies in the categories water management and farm production practices are most often implemented by farmers in the region. The main driver in the area is water scarcity and adaptations often affected water use and resources in addition to farm practices. Subsequently, we studied the spatial context of adaptations by analyzing the location factors of the five main strategies, using Geographic Information Systems and maximum entropy modeling. Our results show that farmers are more likely to adapt in less rural areas with lower poverty values and better market access, and in areas with higher temperatures and less rainfall. This demonstrates that both biophysical and socio-economic factors determine the context in which adaptations are implemented and that considerable spatial variability in the area exists

Impacts of future climate and land use change on water yield in a semi‐arid basin in Iran

Studying the interaction between hydrology, land use and climate change is necessary to support sustainable water resources management. It is unknown how land management interventions in dry climate conditions can benefit water yield in the context of climate and land use change interactions. In this study, we assessed the effects of both land use and climate change on the Mordagh Chay basin water yield using the Integrated Valuation Ecosystem Service and Tradeoffs model (InVEST). First, we modelled the current water yield, followed by developing six combined climate‐land use scenarios until 2030 based on the CCSM4 climate model for the RCP4.5 and RCP8.5 scenarios. We used three future land use scenarios simulated by the Dyna‐CLUE model. The trend scenario of land use change, which does not include any improvements in irrigation efficiency, significantly affected basin water yield under both climate scenarios. Water yield decreases by 19.8% and 31.8% for the RCP4.5 and RCP8.5, respectively. Under all land use scenarios that included improvements in irrigation efficiency the water yield responded positively. For the RCP4.5 scenario, the water yield was projected to increase between 16.6 and 18% depending on the land use scenario. The increase in water yield under the RCP8.5 climate scenario was much lower than for the RCP4.5 scenario (about one third). Overall, the results showed that by adopting appropriate irrigation efficiency, it is possible to achieve a better balance between environmental needs, regional economic and agricultural development. The results provide insight into possible sustainable development options and also provide guidance for managing the other Urmia Lake sub‐basins while the approach of integrated assessment of climate, land use change and land management options is also applicable in other conditions to help inform sustainable management

Scenario analysis for integrated water resources management under future land use change in the Urmia Lake region, Iran

Arid and semi-arid regions are particularly vulnerable to global environmental change because of their fragile climatic conditions. The rapid development of land use is expected to affect aquatic ecosystems in these regions. In this study, we focused on how land use change affects the stream flow and inflow to Urmia Lake in the Mordagh Chay basin, Iran. This case-study exemplifies dynamics found across a much larger region. We mapped changes in land use between 1993–2015 using satellite imagery and modeled future changes using the Dyna-CLUE model. We projected future land use change until 2030 under four scenarios: continuing of the current trend of water use, 40% water withdrawal reduction, and two other scenarios with 40% water withdrawal reduction and improvements of irrigation efficiency up to 50% and 85%. Between 1993–2015, 21% of the study area changed to orchard and arable land mostly at the cost of rangeland. However, upon reduction of water withdrawal our analyses showed that garden must decrease between 27% and 40%. Rainfed cropland is projected to experience a major increase in all scenarios, especially in the case of reduced water withdrawal, where it will increase by 217%. In order to achieve sustainable water resources management land use plays a major role and leads to different land use futures in this type of semi-arid regions

A global reference database of crowdsourced cropland data collected using the Geo-Wiki platform

A global reference data set on cropland was collected through a crowdsourcing campaign using the Geo-Wiki crowdsourcing tool. The campaign lasted three weeks, with over 80 participants from around the world reviewing almost 36,000 sample units, focussing on cropland identification. For quality assessment purposes, two additional data sets are provided. The first is a control set of 1,793 sample locations validated by students trained in satellite image interpretation. This data set was used to assess the quality of the crowd as the campaign progressed. The second data set contains 60 expert validations for additional evaluation of the quality of the contributions. All data sets are split into two parts: the first part shows all areas classified as cropland and the second part shows cropland average per location and user. After further processing, the data presented here might be suitable to validate and compare medium and high resolution cropland maps generated using remote sensing. These could also be used to train classification algorithms for developing new maps of land cover and cropland extent

Beyond land cover change: Towards a new generation of Land Use Models

Land use models play an important role in exploring future land change dynamics and are instrumental to support the integration of knowledge in land system science. However, only modest progress has been made in achieving these aims due to insufficient model evaluation and limited representation of the underlying socio-ecological processes. We discuss how land use models can better represent multi-scalar dynamics, human agency and demand-supply relations, and how we can achieve learning from model evaluation. By addressing these issues we outline pathways towards a new generation of land use models that allow not only the assessment of future land cover pattern changes, but also stimulate envisioning future land use by society to support debate on sustainability solutions and help design alternative solutions

Adaptation of land management in the Mediterranean under scenarios of irrigation water use and availability

Meeting the growing demand for food in the future will require adaptation of water and land management to future conditions. We studied the extent of different adaptation options to future global change in the Mediterranean region, under scenarios of water use and availability. We focused on the most significant adaptation options for semiarid regions: implementing irrigation, changes to cropland intensity, and diversification of cropland activities. We used Conversion of Land Use on Mondial Scale (CLUMondo), a global land system model, to simulate future change to land use and land cover, and land management. To take into account future global change, we followed global outlooks for future population and climate change, and crop and livestock demand. The results indicate that the level of irrigation efficiency improvement is an important determinant of potential changes in the intensity of rain-fed land systems. No or low irrigation efficiency improvements lead to a reduction in irrigated areas, accompanied with intensification and expansion of rain-fed cropping systems. When reducing water withdrawal, total crop production in intensive rain-fed systems would need to increase significantly: by 130% without improving the irrigation efficiency in irrigated systems and by 53% under conditions of the highest possible efficiency improvement. In all scenarios, traditional Mediterranean multifunctional land systems continue to play a significant role in food production, especially in hosting livestock. Our results indicate that significant improvements to irrigation efficiency with simultaneous increase in cropland productivity are needed to satisfy future demands for food in the region. The approach can be transferred to other similar regions with strong resource limitations in terms of land and water

Mediterranean land systems: Representing diversity and intensity of complex land systems in a dynamic region

In the Mediterranean region, land systems have been shaped gradually through centuries. They provide services to a large and growing population in a region that is among the most vulnerable to future global change. The spatial extent and distribution of Mediterranean land systems is, however, unknown. In this paper, we present a new, expert-based classification of Mediterranean land systems, representing landscapes as integrated social-ecological systems. We combined data on land cover, management intensity and livestock available on the European and global scale in a geographic information system based approach. We put special emphasis on agro-silvo-pastoral mosaic systems: multifunctional Mediterranean landscapes hosting different human activities that are not represented in common land cover maps. By analyzing location conditions of the identified land systems, we demonstrated the significance of both bio-physical (precipitation, soil) and socio-economic (population density, market influence) factors driving the occurrence of these systems. Agro-silvo-pastoral mosaic systems were estimated to cover 23.3% of the Mediterranean ecoregion and exhibited to a certain extent similar characteristics as forest and cropland systems. A reanalysis using data that are available with global coverage indicated that the choice of datasets leads to significant uncertainties in the extent and spatial pattern of these systems. The resulting land systems typology can be used to prioritize and protect landscapes of high cultural and environmental significance

Global patterns of land use decision-making

This dataverse present a collection of global land use decision-making patterns spatial distributions. The collection consists of probabilities for two different objectives behind land use change (survival and livelihood, and economic objectives), probability maps for 6 decision-making types that can be found in land-use literature, a probability map for land use diversification, a categorical map combining all decision-making types, and 6 similarity maps (identifying the areas with high or low similarity for each decision-making type). All files are in the geotiff format and can be opened in standard GIS software. Legend files for ArcGIS and QGIS are provided as well, for the categorical map