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Questions: Ants and rodents are recognized as ecosystem engineers worldwide creating soil‐modified nests and adjacent edges with superior resources. The influence of Dipodomys spectabilis (rat) and Pogonomyrmex rugosus (ant) on nests and edges would be similar in burned and unburned habitat on functional groups' cover, density, number of inflorescences and species number. We hypothesize that annual and perennial dicots would recover faster on rat patches than on burned grassland, dicots and grasses would recover faster on ant patches than on burned grassland, and annual dicots would recover faster on rat than on ant patches, whereas grasses would recover faster on ant than on rat patches. Location: Semiarid grassland, Sevilleta National Wildlife Refuge, New Mexico, USA. Methods: We analyzed annual and perennial dicots, grasses and subshrubs in burned and unburned plots at 80 nests during cool‐ and warm‐seasons two years post‐fire. Data were collected at nest top (mound), edge, and 20 m (control) from the edge. Results: Cover, density and species richness of different functional groups were low on animal mounds in unburned and burned plots. Ant edges had greater perennial dicot cover, grass cover and richness while rat edges had lower grass density and richness than control sites at unburned and burned plots. Perennial dicot density and richness recovered faster at rat mounds and edges than control. Ant edges yielded faster recovery of grass inflorescences than control. Dicots recovered faster on rat than ant mounds whereas grasses grew faster on ant edges. Conclusions: Rats create nests enhancing density of recovering dicots and ant edges facilitate reproduction of recovering grasses. Equal regeneration between animal nests and grassland occurred commonly when fire reduced grass competition. Dysochory, granivory and fire intensity may influence recovery. Nests may be sources of reestablishment and seed dispersal. Recovery of grassland may be amplified as plants infill from engineered nests. [ABSTRACT FROM AUTHOR]

Oyster reef living shorelines have been proposed as an effective alternative to traditional coastal defence structures (e.g. bulkheads, breakwaters), with the benefit that they may keep pace with sea‐level rise and provide co‐benefits, such as habitat provision. However, there remains uncertainty about the effectiveness of shoreline protection provided by oyster reefs, which limits their broader application.We draw evidence from studies along the east and gulf coasts of the United States, where much research and implementation of oyster reef restoration has occurred, to better define the existing gaps in our understanding of the use of restored oyster reefs for shoreline protection.We find potential disconnects between ecological and engineering functions of reefs. In response, we outline how engineering and ecological principles are used in the design of oyster reef living shorelines and highlight knowledge gaps where an integration of these disciplines will lead to their more effective application.Synthesis and applications. This work highlights the necessary steps to advance the application of oyster reef living shorelines. Importantly, future research should focus on appropriate designs and conditions needed for these structures to effectively protect our coasts from erosion, while supporting a sustainable oyster population, thereby providing actionable nature‐based alternatives for coastal defence to diverse end‐users. This work highlights the necessary steps to advance the application of oyster reef living shorelines. Importantly, future research should focus on appropriate designs and conditions needed for these structures to effectively protect our coasts from erosion, while supporting a sustainable oyster population, thereby providing actionable nature‐based alternatives for coastal defence to diverse end‐users. [ABSTRACT FROM AUTHOR]

Abstract: Ecological engineering, defined as the design of sustainable ecosystems that integrate human society with its natural environment for the benefit of both, has developed over the last 30 years, and rapidly over the last 10 years. Its goals include the restoration of ecosystems that have been substantially disturbed by human activities and the development of new sustainable ecosystems that have both human and ecological values. It is especially needed as conventional energy sources diminish and amplification of nature''s ecosystem services is needed even more. There are now several universities developing academic programs or departments called ecological engineering, ecological restoration, or similar terms, the number of manuscripts submitted to the journal Ecological Engineering continue to increase at an rapid rate, and the U.S. National Science Foundation now has a specific research focus area called ecological engineering. There are many private firms now developing and even prospering that are now specializing in the restoration of streams, rivers, lakes, forests, grasslands, and wetlands, the rehabilitation of minelands and urban brownfields, and the creation of treatment wetlands and phytoremediation sites. It appears that the perfect synchronization of academy, publishing, research resources, and practice is beginning to develop. Yet the field still does not have a formal accreditation in engineering and receives guarded acceptance in the university system and workplace alike. [Copyright &y& Elsevier]

Abstract: Due to the current environmental problems human societies have to face and the lack of sustainability of most of their activities, the time of Ecological Engineering (EE) has surely come. To assess the development of EE within the academic world we conducted a literature survey based on an exhaustive count of all articles mentioning EE and related terms since the 1980s, and a classification of all articles published in 2008 and 2009 in the journal Ecological Engineering. This survey reveals that EE has quickly developed, and that the journal Ecological Engineering plays a preponderant role in this development. In comparison, articles mentioning the expression “ecological restoration” or “agroecology” were published in many more journals than articles referring to “ecological engineering”. This analysis showed that EE is highly dominated by China and the USA, and by studies aimed at improving the chemical quality of waters (either in natural ecosystems or to treat wastewaters) and aquatic system restoration. Hence, our survey suggests that EE approaches could be widened. These results emphasize the existence of an internal relational challenge for EE, i.e. inside the academic world of ecological sciences. Scientists and engineers from all environmental and ecological sciences must be convinced to take part in the development of this discipline. We explain why meeting this challenge is required for the full development of EE and why this would also highly benefit fundamental ecology. Finally, we give some hints on how to meet this challenge. Reaching this objective should help to bridge the gap between fundamental and applied ecologies and to unify applied ecology. [Copyright &y& Elsevier]

Discusses the use of constructed wetlands to treat water pollution sources, such as domestic wastewater, runoff and seepage from mines, agricultural runoff and polluted runoff from parking lots and airports. Creation of aerobic and anaerobic zones to allow microbes to attack waste streams; Creation of conditions conducive to the growth of desired microorganisms; Ecological engineering in the Arcata Marsh and Wildlife Sanctuary in California.

Human activities are affecting the environment at continental and global scales. An example of this is the Mississippi basin where there has been a large scale loss of wetlands and water quality deterioration over the past century. Wetland and riparian ecosystems have been isolated from rivers and streams. Wetland loss is due both to drainage and reclamation, mainly for agriculture, and to isolation from the river by levees, as in the Mississippi delta. There has been a decline in water quality due to increasing use of fertilizers, enhanced drainage and the loss of wetlands for cleaning water. Water quality has deteriorated throughout the basin and high nitrogen in the Mississippi river is causing a large area of hypoxia in the Gulf of Mexico adjacent to the Mississippi delta. Since the causes of these problems are distributed over the basin, the solution also needs to be distributed over the basin. Ecotechnology and ecological engineering offer the only ecologically sound and cost-effective method of solving these problems. Wetlands to promote nitrogen removal, mainly through denitrification but also through burial and plant uptake, offer a sound ecotechnological solution. At the level of the Mississippi basin, changes in farming practices and use of wetlands for nitrogen assimilation can reduce nitrogen levels in the River. There are additional benefits of restoration of wetland and riverine ecosystems, flood control, reduction in public health threats, and enhanced wildlife and fisheries. At the local drainage basin level, the use of river diversions in the Mississippi delta can address both problems of coastal land loss and water quality deterioration. Nitrate levels in diverted river water are rapidly reduced as water flows through coastal watersheds. At the local level, wetlands are being used to treat municipal wastewater. This is a cost-effective method, which results in improved water quality, enhanced wetland productivity and increased accretion. The problems in the Mississippi basin serves as an example for other watersheds in the Gulf of Mexico. This is especially important in Mexico, where there is a strong need for economical solutions to ecological problems. The Usumacinta delta–Laguna de Terminos regional ecosystem is an example where ecotechnological approaches offer realistic solutions to environmental problems. [Copyright &y& Elsevier]

River diversions within the Mississippi Delta deliver river water and associated sediments and nutrients to interior marshes that were previously isolated from river inputs by elevated levees. When isolated from river inputs, the marshes subside and deteriorate to open water, resulting in ecological and economic losses. River diversions are an ecological engineering method to reverse this trend by restoring controlled flows of river water through modified levees. This study compares the cost of constructing and operating the diversions with potential benefits to determine whether the diversions yield a net public benefit. The Caernarvon and Davis Pond river diversions were evaluated using emergy analysis to provide a common basis to quantify and compare economic and ecological costs and benefits. The analysis quantified high concentrations of natural resources inherent to deltas and demonstrated benefits produced by investing economic resources in river diversions to capture and utilize renewable resources. The diversions resulted in large net emergy yield ratios (33.2 and 9.36) that varied depending on the rate of marsh gain produced by the diversions. [Copyright &y& Elsevier]

Challenges one of the core hypotheses of ecological modernization theory that the design, performance and evaluation of processes of production are increasingly based on ecological criteria in addition to economic criteria. Case of recycling and ecological modernization in the United States; Early history of recycling; Three critiques of ecological modernization.