Defining Recovery Potential in River Restoration: A Biological Data-Driven Approach

Scientists and practitioners working on river restoration have made progress on understanding the recovery potential of rivers from geomorphological and engineering perspectives. We now need to build on this work to gain a better understanding of the biological processes involved in river restoration. Environmental policy agendas are focusing on nature recovery, reigniting debates about the use of “natural” reference conditions as benchmarks for ecosystem restoration. We argue that the search for natural or semi-natural analogues to guide restoration planning is inappropriate due to the absence of contemporary reference conditions. With a catchment-scale case study on the invertebrate communities of the Warwickshire Avon, a fifth-order river system in England, we demonstrate an alternative to the reference condition approach. Under our model, recovery potential is quantified based on the gap between observed biodiversity at a site and the biodiversity predicted to occur in that location under alternative management scenarios. We predict that commonly applied restoration measures such as reduced nutrient inputs and the removal of channel resectioning could be detrimental to invertebrate diversity, if applied indiscriminately and without other complementary measures. Instead, our results suggest considerable potential for increases in biodiversity when restoration measures are combined in a way that maximises biodiversity within each water body.

Is the South-Mediterranean Canopy-Forming Ericaria giacconei (= Cystoseira hyblaea) a Loser From Ocean Warming?

Canopy-forming brown algae support highly productive ecosystems whose decline has been attributed to the interplay of several anthropogenic disturbances. Climate change could have disruptive effects on the biology of these species, but the role of temperature in the development of early life stages is poorly understood. The aim of this study was to assess the response of Ericaria giacconei, a winter-reproducing Southern–Mediterranean endemic species, to thermal stress by testing five temperatures (12, 15, 18, 24, and 28°C) on adults and early stages. Chlorophyll a fluorescence of adult plants was measured at 0, 24, 72, and 120 h on nine fronds in each of the three aquaria per treatment. To assess egg release, zygote settlement, and embryo growth rate, approximately 1,200 receptacles were cultured on six Petri dishes per temperature treatment, and 10 random subsections of 2 ×2 mm were examined in three Petri dishes at 0, 20, 44, and 92 h after fertilization. Adult plants showed a plastic physiological response, and thermal stress had no significant effect on PSII efficiency. Embryos fully developed only at 12 and 15°C. Mortality increased at 18 and 24°C, and no zygotes survived at 28°C. In a scenario of further increasing temperatures, the effects of warming could affect the recruitment of E. giacconei and increase its vulnerability to further stresses. These effects on the survival of early stages, which are the bottleneck for the long-term survival of the species, should be taken into account in conservation and restoration measures to maintain canopy-forming macroalgal populations and associated biodiversity and ecosystem services.

THE MACROPHYTE FLORA AND VEGETATION OF THE PAUČKO LAKE (MT. KONJUH)

UDK: 581.9:574.5 (497.6) (285) The study presents the first data on biodiversity of macrophyte flora and vegetation of Paučko Lake, which is recognized as an area of great natural, landscape and hydrological value in the Protected Landscape “Konjuh”. Paučko Lake has a small surface and it’s located at 711 m a.s.l. in the catchment area of the Drinjača River. The aquatic and marsh vegetation were studied during spring and summer in 2018 using the traditional Zürich-Montpellier approach. The vegetation of Paučko Lake is comprised of aquatic and marsh associations of the classes Potamogetonetea Klika in Klika et Novák 1941 and Phragmito-Magnocaricetea Klika in Klika et Novák 1941. The following aquatic and marsh plant associations were identified: Myriophyllo-Potametum Soó 1934, Scirpo-Phragmitetum australis W. Koch 1926, Thelypterido palustris-Phragmitetum australis Kuiperex van Donselaar et al. 1961, Schoenoplectetum lacustris Chouard 1924, Typhetum latipholiae Lang. 1973 and Scirpetum silvatici Ht et H-ić prov. (in Ht et al.1974). Rare vulnerable taxa Thelypteris palustris Schott and Menyanthes trifoliata L. were recorded in emerged littoral communities, whose habitats are under successional changes caused by excessive macrophyte overgrowth by competitor species. Restoration measures are necessary to be taken to preserve the habitats of endangered species of the Paučko Lake.

Recovery and Restoration of Biloxi Marsh in the Mississippi River Delta

The State of Louisiana is leading an integrated wetland restoration and flood risk reduction program in the Mississippi River Delta. East of New Orleans, Biloxi Marsh, a ~1700 km2 peninsula jutting 60 km north toward the State of Mississippi is one of few Delta wetland tracts well positioned to dissipate hurricane surge and waves threatening the city’s newly rebuilt hurricane flood defenses. Both its location on the eastern margin of the Delta, and its genesis as the geologic core of the shallow water St. Bernard/Terre aux Boeuf sub-delta, which was the primary Mississippi outlet for almost 2000 years, make Biloxi Marsh attractive for restoration, now that the Mississippi River Gulf Outlet deep-draft ship channel has been dammed, and 50 years of impacts from construction and operation have abated. Now, the cascade of ecosystem damage it caused can be reversed or offset by restoration projects that leverage natural recovery and increased access to suspended sediment from the Mississippi River. Biloxi Marsh is (1) geologically stable, (2) benefiting from increased input of river sediment, and (3) could be restored to sustainability earlier and for a longer period than most of the rest of the submerging Mississippi Delta. The focus of this review is on the Biloxi Marsh, but it also provides a template for regional studies, including analysis of 2D and 3D seismic and other energy industry data to explore why existing marshes that look similar on the ground or from the air may respond to restoration measures with different levels of success. Properties of inherent durability and resilience can be exploited in restoration project selection, sequencing and expenditure. Issues encountered and investigative methods applied in the Biloxi Marsh are likely to resonate across initiatives now contemplated to sustain valuable river deltas worldwide.

Information and analytical system for environmental monitoring of water bodies

An integral part of maintaining a favorable environmental situation on our planet is the observation of its individual objects, including special attention is paid to water bodies. This is due not only to the natural human need for its consumption, but also to other aspects of the anthropogenic factor, which includes unintentional pollution of the environment with industrial and other waste. The task of increasing the effectiveness of measures aimed at the effective performance of work on the collection of water and soil samples from individual reservoirs, as well as the collection, accumulation and processing of data on reservoirs through the introduction of a system of environmental monitoring of water bodies is being solved. Such a system will speed up the work of environmental organizations, and also contributes to the formation of a brief set of recommendations for restoration measures and will give an overall assessment of the ecological state of the reservoir. The purpose of this work is to automate the process of accounting and processing information about the results of laboratory studies of various types of samples and tests on the basis of the performed cycle of calculations to form estimates and recommendations on the ecological state of the reservoir and to make final reports.