Riparian areas, especially in the Mediterranean, offer many ecosystem services for the welfare of society benefits from their sustainable management. This study presents different tools used to assess riparian areas of Greece and their results. Riparian areas with different land-uses/vegetation covers along streams or torrents were assessed. The assessment tools were visual protocols, bioindicators, geographic information systems (GIS), vegetation indices, and a model. These tools differ in scale, accuracy, and difficulty of implementation. The riparian areas had Low and Moderate quality in Greece because of agricultural activities and hydrologic alterations. Vegetation appeared more important for the integrity of riparian areas than stream flow (perennial or intermittent). In addition, territorial variables (distance from dam and sea) were more influential compared to climatic variables. Visual protocols and GIS were effective for preliminary assessments. GIS can be applied at a greater scale but was less accurate than the protocols. Bioindicators can provide more cost-effective monitoring than physicochemical water variables. Finally, vegetation indices and models can be used for larger spatial and temporal scales, but require specialized personnel. Overall, riparian areas of Greece seem to be degraded, and monitoring would contribute to the development of a database on riparian areas that should form the basis for sustainable management plans in Greece.

The study attempts to monitor geomorphological changes (e.g., erosion/deposition) with innovative tools at a typical Mediterranean torrent. The torrent’s geomorphological conditions are studied for an entire affected stream reach. The investigation utilizes two different environments/point views: (a) traditional terrestrial and (b) innovative aerial. The traditional methods include erosion pins at streambanks and field cross-section measurements of the stream channel. For the innovative methods, utilizing an unmanned aerial vehicle, in order to monitor the geomorphologic changes in the entire reach during different days over the last 3 years (2020–2022), there was a total of six flights. The results from innovative methods showcase the episodic nature of stream channel changes since erosion and deposition were captured during the different monitoring periods. Even during one flight in one cross-section, the stream bed and two banks in many cases experienced different changes. The significant erosion and deposition recorded showcase the disequilibrium in the torrent. In addition, the impact of the anthropogenic structure (Irish bridge) is evident, since upstream, more substantial deposition was recorded compared to downstream. The similarity of the results between the innovative method and the traditional methods indicates the method’s effectiveness and the potential usefulness in using UAV images for stream bank and bed monitoring. One of the biggest advantages is the ability to monitor the entire reach at substantially lower costs and time compared to the traditional methods. Still, more testing needs to be conducted in different stream and river environments to better refine the method in order to be adopted by land and water managers to be used for stream and river monitoring.

Riparian areas offer many ecosystem services, especially in urban settings. Their conservation can be complex because of the many urban anthropogenic pressures they face. Adopting new technological approaches can provide insights on the most cost-effective and sustainable management for riparian areas. In this study, different new technological approaches were implemented to assess and map environmental variables and find the optimal location of nature-based solutions (e.g., litter traps). The study area was Agia Varvara Park in Drama, Greece, a unique natural urban riparian area. The approaches utilized were categorized as aerial, terrestrial, and surface/underwater. Specifically, these approaches included unmanned aerial vehicles that incorporated high-resolution regular and thermal cameras to capture the surface environmental conditions and unmanned underwater vehicles to capture the underwater environmental conditions. The produced orthomosaics and digital surface models enabled us to estimate the boundaries of the water surface in Agia Varvara Park. A GPS tracker was also used to record the potential movement route of litter. Finally, a sonar device was utilized to estimate the water depth of potential cross-sections of Agia Varvara’s stream where the litter trap could be installed. The above datasets were used to develop spatial datasets and accompanying maps that were utilized to find the optimal opportunity sites for the litter trap. A litter trap is a floating device that gathers and maintains litter, vegetation, and other debris. Two specific locations were proposed based on water presence, water depth, channel’s width, limited vegetation for accessibility, wildlife existence, litter’s water route, and stopping location time. Such traps enable the collection of anthropogenic litter. In one location, a litter trap has been installed and is being tested. Overall, the above approaches could be used to suggest other nature-based solutions and/or their optimal location, thus enhancing the sustainable management of urban riparian areas.

The riparian areas of the Mediterranean are unique but face many pressures from anthropogenic and climate change impacts. They have very rich and diverse plant communities as a result of the dynamic fluvio-geomorphologic conditions of the Mediterranean streams. In this study, the riparian areas of two adjacent mountainous tributaries (Arkoudorema and Vathirema) of the Nestos River were studied. To assess the condition of riparian areas holistically, diverse measurements are required. This is why fluvio-geomorphologic (in the field and with GIS), vegetation (surveys and visual protocols) and ground-dwelling insect (pitfall traps and indices) measurements were taken along an elevational gradient. The results of all three methodologies draw to similar conclusions, with Vathirema sub-watershed riparian areas being in better condition than Arkoudoreama. This was expected, since Vathirema has less anthropogenic pressures. In addition, the riparian areas in higher elevations were in better condition for the same reason. To implement integrated water resources management plans, fluvio-geomorphologic and biological (e.g., vegetation and insects) datasets are required to provide a holistic view on the watershed and riparian area conditions. For the studied sub-watersheds, we recommend these measurements to continue, to record the current anthropogenic pressures and based on this information to suggest best management practices that will secure long-term sustainability.