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Temporary streams are defined by periodic flow cessation, and may experience partial or complete loss of surface water. The ecology and hydrology of these transitional aquatic-terrestrial ecosystems have received unprecedented attention in recent years. Research has focussed on the arid, semi-arid, and Mediterranean regions in which temporary systems are the dominant stream type, and those in cooler, wetter temperate regions with an oceanic climate influence are also receiving increasing attention. These oceanic systems take diverse forms, including meandering alluvial plain rivers, 'winterbourne' chalk streams, and peatland gullies. Temporary streams provide ecosystem services and support a diverse biota that includes rare and endemic specialists. We examine this biota and illustrate that temporary stream diversity can be higher than in comparable perennial systems, in particular when differences among sites and times are considered; these diversity patterns can be related to transitions between lotic, lentic, and terrestrial instream conditions. Human impacts on temperate-zone temporary streams are ubiquitous, and result from water-resource and land-use-related stressors, which interact in a changing climate to alter natural flow regimes. These impacts may remain uncharacterized due to inadequate protection of small temporary streams by current legislation, and hydrological and biological monitoring programs therefore require expansion to better represent temporary systems. Novel, temporary-stream-specific biomonitors and multi-metric indices require development, to integrate characterization of ecological quality during lotic, lentic, and terrestrial phases. In addition, projects to restore flow regimes, habitats, and communities may be required to improve the ecological quality of temporary streams

This is an Open Access Article. It is published by Wiley under the Creative Commons Attribution 4.0 Unported Licence (CC BY). Full details of this licence are available at: http://creativecommons.org/licenses/by/4.0/ ; Temporary streams are defined by periodic flow cessation, and may experience partial or complete loss of surface water. The ecology and hydrology of these transitional aquatic-terrestrial ecosystems have received unprecedented attention in recent years. Research has focussed on the arid, semi-arid, and Mediterranean regions in which temporary systems are the dominant stream type, and those in cooler, wetter temperate regions with an oceanic climate influence are also receiving increasing attention. These oceanic systems take diverse forms, including meandering alluvial plain rivers, 'winterbourne' chalk streams, and peatland gullies. Temporary streams provide ecosystem services and support a diverse biota that includes rare and endemic specialists. We examine this biota and illustrate that temporary stream diversity can be higher than in comparable perennial systems, in particular when differences among sites and times are considered; these diversity patterns can be related to transitions between lotic, lentic, and terrestrial instream conditions. Human impacts on temperate-zone temporary streams are ubiquitous, and result from water-resource and land-use-related stressors, which interact in a changing climate to alter natural flow regimes. These impacts may remain uncharacterized due to inadequate protection of small temporary streams by current legislation, and hydrological and biological monitoring programs therefore require expansion to better represent temporary systems. Novel, temporary-stream-specific biomonitors and multi-metric indices require development, to integrate characterization of ecological quality during lotic, lentic, and terrestrial phases. In addition, projects to restore flow regimes, habitats, and communities may be required to improve the ecological quality of temporary streams.

In Southwest Germany, the renaturation of quarry areas close to settlements is usually based on the planting of native species of trees and shrubs, which are then neither cultivated nor used. This study investigates whether a species-rich agroforestry system based on Ernst Goetsch's syntropic agriculture approach would be suitable for both renaturation in the form of soil fertility improvement and diverse food crop production under temperate climate. The quarry syntropy project was launched in summer 2019. Two shallow stony sections of a spoil heap of the quarry in Ehningen, Southwest Germany were available for demonstration plots. An interdisciplinary project team was set up both to obtain the ocial permits from five governmental institutions and to begin the study. The demonstration plots were each divided into three broad strips, which dier in three vegetation types: trees, shrubs, and annual food crops. The tree and shrub areas are mainly used for biomass production for a continuous mulch supply on the entire cultivated area in order to rapidly increase soil fertility. The food crops and also partly the trees and shrubs were intended to provide organically produced food (vegetables, fruit, berries and herbs). Most of the trees (eleven species) were planted in November 2019. In March 2020, soil samples were taken (0–30 cm), and a solar-powered water storage system was installed. Currently, the shrub and annual food crop strips are under preparation (pre-renaturation phase). In this initial phase, the priority is fertility improvement of the topsoil through intensive mulching of the existing grassland stock dominated by top grasses and the legumes hybrid alfalfa (Medicago varia Martyn) and common bird's-foot trefoil (Lotus corniculatus L.). The food crop strip should then start in 2021 after one year of mulching. Depending on the success of growth, the tree strips should then also gain in importance for mulch application in the following years. The strategy is to gradually build up food crop cultivation under ...