Assessing Riparian Areas of Greece—An Overview

Abstract

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.

Riparian Ecological Infrastructures: Potential for Biodiversity-Related Ecosystem Services in Mediterranean Human-Dominated Landscapes

“…The reduced accessibility of riparian areas located in the FP landscape, with steep slopes and rocky formations, discourages human intervention in REIs and allows their expansions outwards from the active channel. Other studies suggest that habitat quality in Mediterranean riparian areas tends to increase with decreasing human pressure and increasing forest cover in the river surroundings [90,91]. The majority of dominant native trees found within SUs were either obligate or preferential riparian species, except for the FP landscape where riparian areas were dominated by cork oak trees.…”

“…In undisturbed conditions, breeding bird species richness describes a linear increase from the pioneer herbaceous communities of headwaters to the canopy forest of lowland large streams [7], but this was not reflected in the proportion of Sus with HEIDI scores of "high" for the Seed production suitability metric. Some studies suggest that this phenomenon may be a consequence of an upstreamdownstream anthropogenic gradient, where Mediterranean headwaters contain forested areas with less anthropogenic impact and flat lowlands are highly impacted by agricultural activities [90][91][92]. Additionally, increasing levels of birds and non-flying mammals' biodiversity have been previously reported for riparian habitats embedded in agroforestry landscapes when compared to agricultural areas and forest production systems [73,93].…”

“…Riparian Ecological Infrastructures are located in heavily degraded riparian areas, due to the human-dominated nature of the landscape in which they are embedded. Zaimes and Iakovoglou [91] identified that for Mediterranean regions, the ecological status of riparian areas should be monitored using small-scale tools (e.g., protocols and bioindicators). The HEIDI may contribute to such assessment, by incorporating habitat quality features that have a direct known relationship with the diversity of distinct faunistic groups.…”

Pressures and Status of the Riparian Vegetation in Greek Rivers: Overview and Preliminary Assessment

“…Hence, hydromorphological assessments incorporate the evaluation of the riparian vegetation status placing emphasis on various features such as the total cover, the cover structure and the continuity along the riparian corridor. These assessments of riparian zone that are using various protocols and indices are in global practice [7,8,16,[21][22][23][24][25]. According to historical sources [26], from the beginning of the Middle Ages, various interventions took place in the riparian zones of the Mediterranean rivers, aiming to protect crops, livestock, and humans, living in areas susceptible of flooding.…”

“…Through their functions, they strongly influence the biodiversity as well as the landscape of an area. However, the assessment of riparian zones, and specifically the assessment of riparian vegetation, is not often included in research concerning the evaluation of the ecological status of rivers, despite their importance [7]. This is evident in various Mediterranean countries, including Greece [8].…”