Agriculture impacts the ecological status of freshwaters through multiple pressures such as diffuse pollution, water abstraction, and hydromorphological alteration, strongly impairing riverine biodiversity. The agricultural effects, however, likely differ between agricultural types and practices. In Europe, agricultural types show distinct spatial patterns related to intensity, biophysical conditions, and socioeconomic history, which have been operationalised by various landscape typologies. Our study aimed at analysing whether incorporating agricultural intensity enhances the correlation between agricultural land use and the ecological status. For this, we aggregated the continent's agricultural activities into 20 Areas of Farming-induced Freshwater Pressures (AFFP), specifying individual pressure profiles regarding nutrient enrichment, pesticides, water abstraction, and agricultural land use in the riparian zone to establish an agricultural intensity index and related this intensity index to the river ecological status. Using the agricultural intensity index, nearly doubled the correlative strength between agriculture and the ecological status of rivers as compared to the share of agriculture in the sub-catchment (based on the analysis of more than 50,000 sub-catchment units). Strongest agricultural pressures were found for high intensity cropland in the Mediterranean and Temperate regions, while extensive grassland, fallow farmland and livestock farming in the Northern and Highland regions, as well as low intensity mosaic farming, featured lowest pressures. The results provide advice for pan-European management of freshwater ecosystems and highlight the urgent need for more sustainable agriculture. Consequently, they can also be used as a basis for European Union-wide and global policies to halt biodiversity decline, such as the post-2027 renewal of the Common Agricultural Policy.

The Ali Efenti catchment is a rural upstream subcatchment of the Pinios river basin that suffers from seasonal water shortages due to the rapid increase of the total water abstraction in the summer months, which is mainly attributed to local crop irrigation. Catchment modelling is being implemented using two different modelling approaches: a conceptual model based on water balances, the Water Evaluation And Planning system (WEAP), and a physically-based model coupled with routines for irrigation and crop growth, the Soil and Water Assessment Tool (SWAT). Both models were set up, calibrated and validated using observed streamflows. The strengths of the two models were combined in order to design effective, efficient and comprehensive demand-side measures for the urban, tourism, industrial and agricultural sectors to achieve sustainable water management in the Ali Efenti catchment. The comparison of the two models and the results of modelling are being discussed

The Pinios river basin is a major agricultural area in Greece, which faces environmental issues with water scarcity and nutrient pollution. Recent Earth Observation satellite data and ground truth information were combined to produce an updated land use map, focusing on irrigated crop areas. A process-based hydrological model (SWAT) was set up using the produced land use map. The model was calibrated and validated using observed streamflows and nutrient concentrations at selected gauging stations. Four irrigation and nutrient management practices related to resource efficiency (i.e. deficit irrigation, reduced fertilization, combination of deficit irrigation and fertilization, precision agriculture) were modelled and simulated. The sustainability of the management practices was assessed using indicators to quantify their impacts on the water-energy-land-food nexus of the river basin

The Ali Efenti catchment is a rural upstream subcatchment of the Pinios river basin in central Greece. The average annual precipitation in this subcatchment is relatively higher and groundwater recharge is relatively faster than in the rest of the river basin. Yet, seasonal water shortages occur due to the rapid increase of water abstractions in the summer months, mainly for crop irrigation. Up until 2030 the gap between water supply and demand is expected to deteriorate, considering the impacts of climate and socio-economic change. The adoption of environmental restrictions on water abstraction, which is a measure foreseen in the local river basin management plan, could decrease water stress substantially from 19.2% to 13.9%. However, this would require enormous (−26%) cuts in the current water abstractions during June–September, lowering water demand coverage from 86% to 68%. Optimal combinations of measures, from an economic and environmental perspective, will need to be designed to bridge the gap between water supply and demand and restore water demand coverage to satisfactory levels. Hydrologic and water resources management modelling has been implemented using the Water Evaluation and Planning system (WEAP), which is a conceptual model based on water balances.