Wildlife habitat and public use benefits of treatment wetlands

1997 ◽  
Vol 35 (5) ◽  
pp. 35-43 ◽  
Author(s):  
Robert L. Knight

Constructed and natural wetlands are being utilized for water quality management of a broad variety of wastewater types worldwide. While water treatment is a primary goal of many of these systems, there is a general recognition that ancillary benefits for public use and wildlife habitat are typical of some of these wetlands. Also, there are growing numbers of constructed wetlands that are primarily focused on providing habitat and/or public use while relying on pretreated wastewater as the principal water supply. Efforts are currently underway to document the normal ranges of human and wildlife use benefits of treatment wetlands, and to provide a reasoned assessment of the potential environmental risks associated with these systems. Information collected from existing surface-flow treatment wetlands indicates consistent net benefits for wildlife habitat and public use. An understanding of the relationship between design and operation of treatment wetlands, and their positive and negative ecological and societal responses, will allow for optimization of new wetland systems.

2001 ◽  
Vol 44 (11-12) ◽  
pp. 27-37 ◽  
Author(s):  
R.L Knight ◽  
R.A. Clarke ◽  
R.K. Bastian

Water quality improvement is generally the primary objective of treatment wetlands. Creation of wildlife habitat is an inevitable outcome of these projects. However, an increasing number of treatment wetland projects have been purposely designed and operated to enhance their beneficial utility to wildlife and humans. This trend to multi-purpose treatment wetlands has broadened the basis for assessing the advantages of this natural treatment alternative. There are at least 21 treatment wetlands in the U.S. that were implemented with wildlife habitat creation and/or human use as principal goals. A number of treatment wetlands outside the U.S. also share these priorities. Hundreds of other wetlands have collected and reported quantitative data on wildlife and/or human uses. The North American Treatment Wetland Database (NADB) has been expanded to include critical wildlife habitat and human use data. This paper provides a preliminary inventory of these habitat and human use treatment wetlands, summarizes lessons learned, and identifies additional data needs.


Author(s):  
Robin Björkas ◽  
Mariah Larsson

AbstractSex dolls are a complex phenomenon with several diverse possible emotional, sexual and therapeutic uses. They can be part of a broad variety of sexual practices, and also function as a sexual aid. However, the media discourse on sex dolls first and foremost concerns how we perceive the relationship between intimacy and technology. A critical discourse analysis of the Swedish media discourse on sex dolls reveals six themes which dominate the discourse: (a) the definition of what a human being is; (b) a discourse on the (technological and existential) future; (c) a social effort; (d) a loveless phenomenon; (e) men’s violence against women; and (f) pedophilia. Accordingly, this discourse is very conservative and normative in its view of sexuality, technology, and humanity. Overall, the dominant themes do not provide any space for positive effects of technology on human sexuality, and if they do, it is usually as a substitute for something else.


1997 ◽  
Vol 35 (5) ◽  
pp. 11-17 ◽  
Author(s):  
Hans Brix

The larger aquatic plants growing in wetlands are usually called macrophytes. These include aquatic vascular plants, aquatic mosses and some larger algae. The presence or absence of aquatic macrophytes is one of the characteristics used to define wetlands, and as such macrophytes are an indispensable component of these ecosystems. As the most important removal processes in constructed treatment wetlands are based on physical and microbial processes, the role of the macrophytes in these has been questioned. This paper summarizes how macrophytes influence the treatment processes in wetlands. The most important functions of the macrophytes in relation to the treatment of wastewater are the physical effects the presence of the plants gives rise to. The macrophytes stabilise the surface of the beds, provide good conditions for physical filtration, prevent vertical flow systems from clogging, insulate the surface against frost during winter, and provide a huge surface area for attached microbial growth. Contrary to earlier belief, the growth of macrophytes does not increase the hydraulic conductivity of the substrate in soil-based subsurface flow constructed wetlands. The metabolism of the macrophytes affects the treatment processes to different extents depending on the type of the constructed wetland. Plant uptake of nutrients is only of quantitative importance in low-loaded systems (surface flow systems). Macrophyte mediated transfer of oxygen to the rhizosphere by leakage from roots increases aerobic degradation of organic matter and nitrification. The macrophytes have additional site-specific values by providing habitat for wildlife and making wastewater treatment systems aesthetically pleasing.


2019 ◽  
Vol 13 (3) ◽  
pp. 517-539 ◽  
Author(s):  
María Cecilia Chiappini ◽  
Kris Scheerlinck ◽  
Yves Schoonjans

Purpose The purpose of this paper is to investigate ways of practicing political power in public space in the interaction between central and marginal users in Glòries, an area under transformation in Barcelona. Originally conceived as the core of its extension, Glòries is now a battle field where conflictive spatial-social manifestations are strongly linked to pending conditions and partially implemented infrastructural projects. The key actors are in large majority illegal migrants, which activities and spatial strategies are particularly uncomfortable for city administrators; challenging the traditional focus on actors that are stable and institutionalized, included and previewed by the tools for urban projects implementation. Design/methodology/approach To achieve insights on urban spatial articulations of appropriations by marginal actors around infrastructures, the method deployed is to look closely at the interplays between persecuted and persecutors and their ways of practicing power in space in the frame of the illegal street markets in Glòries. This is part of an ongoing PhD research on the complexity of involved processes. The research is executed in diverse work packages: mapping of material transformations (morphology, domain, accessibility and permeability), in diverse timeframes; surrounding functions and temporal fixities, appropriations catalysts; media presences and discussions; crossed references with immersive field work and exchange with locals. Findings A broad variety of illegal street markets have been monitored in Glòries, revealing an increase in scale, frequency and levels of tension. Around them, their dynamic properties can be extracted and measured: spatial configurations, sizes, timeframes, number of traders/visitors, the relation to other elements, the strategies of displaying, displacing and dispersing used by the police. In all, the relationship with the infrastructural elements shows crucial and a better understanding of their relations constitutes a path to understand how both infrastructures and collective behavior contribute to dynamic productive and power logics in space. Originality/value This research and case study are an outstanding framework to explore the concrete spatial interactions and interplays of different power or territorialization processes, i.e. the strategies to denote presence and agency – in novel ways. Focusing on their spatial outcomes in contemporary transformation processes where infrastructures are dominant components is a way to inform the design, practice and implementation of city project and management.


2000 ◽  
Vol 2000 (13) ◽  
pp. 253-271
Author(s):  
J. Kimmelshue ◽  
M. Dellinger ◽  
R. Langis ◽  
J. Bays

2007 ◽  
Vol 550 ◽  
pp. 193-198
Author(s):  
Edgar F. Rauch ◽  
G. Shigesato

The dislocation substructure that appears in deformed metals and alloys have been extensively investigated in the past by transmission electron microscopy (TEM). They are known to form a broad variety of microstructures. These substructures are characterized by three main parameters, namely the density of the dislocations that are trapped in the tangles, their degree of patterning and the misorientation between the cells. The aim of the present work is to investigate the relationship between these features and the mechanical properties of the material.


2004 ◽  
Vol 19 (1) ◽  
pp. 42-46 ◽  
Author(s):  
Robert L. Mathiasen ◽  
Gregg N. Garnett ◽  
Carol L. Chambers

Abstract Dwarf mistletoe infections often induce structures known as witches' brooms that may provide an important wildlife habitat element. We compared evidence of wildlife use in broomed and unbroomed ponderosa pine trees at 12 mistletoe-infested sites in northern Arizona. We systematically sampled 12 broomed and unbroomed trees on each site (n = 144 broomed and 144 unbroomed trees) by climbing and inspecting each tree to document evidence of wildlife use. Broomed trees were used more frequently than unbroomed trees for wildlife activities including foraging/caching, nesting, and roosting/resting sites. We observed evidence of use by Abert squirrel (Sciurus aberti), porcupine (Erethizon dorsatum), and passerine birds in witches' brooms. Of the 226 brooms we examined, 23% (n = 52) contained evidence of wildlife use. Mammal use was found in 80% (n = 42) of the brooms and of these, 39 were used by Abert squirrel. We recommend that management agencies consider retaining some of these broomed trees to provide habitat for wildlife. West. J. Appl. For. 19(1):42–46.


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