Can climate change explain increases in DOC flux from upland peat catchments?

Long-term increases in DOC concentration in rivers draining areas of upland peat are a ubiquitous phenomenon in the UK. Several hypotheses have been proposed to explain these increases, but one compelling explanation is the observed long-term increase in temperature in UK uplands causing increases in peat decomposition rates, and increasing the depth of oxidation as evaporation increases depth to the water table. The study constructed an empirical model for water table depth and decomposition rate calibrated against observations from the Environmental Change Network monitoring site at Moor House in the North Pennines, UK. The study shows: (i) Depth of the water table has not changed significantly over a 30-year period, reflecting the fact that blanket peat is well buffered against climate change. (ii) Increases in temperature are responsible for a 12% increase in DOC production while an approximate 78% increase in DOC production has been observed. (iii) Overall DOC production is predicted to rise by 6% but observation suggests increases on the scale of 97%. (iv) The model inadequately represents changes in production and supply of DOC during periods of severe drought. The study shows that temperature change alone is insufficient to explain observed increases in DOC production. Alternative explanations for large increases in DOC production could include changes in land management, but an enzymic latch mechanism, i.e. derepression of anaerobic degradation, causing increased decomposition rates in response to severe drought is preferred.     

Tangshan—China's one time industrial pioneer striving for ecological excellence

Tangshan is one of China's oldest industrial cities, indeed its developmental trajectory well reflects China's modern industrial history. However, what brought the city notoriety was a magnitude 7.8 earthquake in 1976, which killed 203,555 people, severely injured 137,753 more, and destroyed over 90% of the houses and roads overnight. Forty years later Tangshan has been rebuilt into a city driven by up-to-date planning imperatives and high urban synergy which have resulted in an improved quality of life, attractive ecological environments and the urban leadership's enthusiasm for sustainable development. This paper discusses Tangshan's industrial history, painful lessons from the earthquake, and re-development, including the port of Caofeidian and the new town of Nanhu, as well as challenges and prospects for the future.     

Can Architectural Design Be Research?

So far the Unit Factor series has focused on design research within the context of the Architectural Association in London. Here the series editor, Michael Weinstock, discusses the possibilities of architects undertaking research in practice. He draws on the experience of Chris Bosse, who is responsible for the competition-winning design for the Watercube, Beijing's National Swimming Centre. Copyright © 2008 John Wiley & Sons, Ltd.     

Combining HPLC pigment markers and ecological similarity indices to assess phytoplankton community structure: an environmental tool for eutrophication?

A new tool combining the use of HPLC pigment markers with ecological similarity indices, to provide a fast and effective environmental tool for monitoring water quality, was investigated. HPLC pigment concentrations from a 4-year time series data set (2000-2003) from the western English Channel were used to calculate six similarity indices to assess changes in phytoplankton community structure. Indices obtained from HPLC data were compared with those produced from the corresponding phytoplankton biomass derived from microscopic analysis. Multivariate RELATE analyses (P<0.001) suggested that there was little loss of information when species biomass data were grouped into higher taxonomic levels, thereby providing justification for the use of pigment markers. To test the proposed methodology, product moment (r) and Spearman's rank (r(s)) correlation analyses were performed. Highly significant correlations (P<0.01, Canberra Metric: P<0.05) between percentage similarities derived from phytoplankton class biomass and pigment markers were found for all indices when data were pooled (n=104). A Mann-Whitney U-test suggested that indices were more sensitive to changes in relative biomass than pigment concentrations; however, pigment data also produced statistically significant findings (P<0.05). Combining HPLC pigment markers and ecological similarity indices to assess phytoplankton community structure has advantages over microscopy in that it is rapid, reproducible and better suited to large-scale environmental monitoring. We present a basic protocol for implementing this new tool using a suite of similarity indices into environmental monitoring of phytoplankton communities.     

What will the neighbors think? Cultural norms and ecological design

Cultural norms for landscape appearance may affect preferences for and adoption of ecological design in exurban residential landscapes, a rapidly growing land use that covers a larger area than all other urban land uses in America combined. We conducted an image-based web survey of 494 southeast Michigan exurban homeowners to investigate the influence of implicit neighborhood norms as well as broader cultural norms on individual preferences for six alternative front yard designs ranging from conventional yards dominated by mown turf to mature native woodlands and native prairie garden designs. Respondents were randomly assigned to see images of one of three types of nearby neighbors’ yards: all conventional, all ecologically innovative, or a mix. They rated front yard design alternatives in one of these three neighborhood contexts. Both broad cultural norms for conventional front yards and neighborhood norms significantly affected homeowners’ preference for their own yards. However, neighborhood norms most dramatically affected preference: the rank of the most conventional and most ecologically beneficial front yard designs was reversed depending upon the design of nearby neighbors’ yards. We conclude that efforts to introduce ecologically innovative designs to metropolitan residential landscapes should approach change at the neighborhood scale in order to enhance initial success and long term cultural sustainability. We also note that individuals who innovate on their own properties may want to enlist nearby neighbors in similar innovations to create a threshold of cultural sustainability.     

Can privatization of distribution substations improve electricity reliability for non-residential customers? An application to Nepal

This paper takes on a novel perspective to the overloading of distribution substations by considering the common-pool characteristics of electric infrastructure capacity. Using firm- and substation-level data from Nepal, the results provide evidence of common-pool resource (CPR) problems across substations’ ownership boundaries: firms with captive substations experience fewer and shorter unplanned outages than firms connected to shared substations. Based on these findings, private investments in captive substations emerge as a coping mechanism for firms against unreliable electricity supply. A generalized cost-benefit analysis framework for such investments is developed and used to quantify the benefits to Nepalese non-residential customers.     

Is ecosystem structure the target of concern in ecological effect assessments?

The species sensitivity distribution, a technique currently used to derive water-quality standards of chemicals, is associated with a set of inadequately tested assumptions. One of these assumptions is that ecosystem structure is as or more sensitive than ecosystem function, i.e., that structure is the target of concern. In this paper, we tested this assumption for a simple freshwater ecosystem exposed to different toxicants. Using an ecosystem model, we calculated no observed effect concentrations (NOECs) for ecosystem structure (ecosystem structure-NOECs) and function (ecosystem function-NOECs) for each of 1000 hypothetical toxicants. For 979 of these toxicants, the ecosystem structure-NOEC was lower than or equal to the ecosystem function-NOEC, indicating that the tested assumption can be considered valid. For 239 of these 979 toxicants, both NOECs were equal. For half of the 1000 toxicants, the structure of lower trophic levels (i.e., phytoplankton) appears to be more sensitive than the structure of higher trophic levels (i.e., fish). As such, ecosystem structure-NOECs are primarily determined by the sensitivity of the structure of lower trophic levels. In contrast, ecosystem functions associated with higher trophic levels (e.g., total ingestion by fish) are more sensitive than functions associated with lower trophic levels (e.g., total photosynthesis by phytoplankton) for 749 toxicants.     

Can simplified design methods for domestic rainwater harvesting systems produce realistic water‐saving and financial predictions?

Rainwater harvesting systems are a recognised approach for reducing reliance on potable mains supply. Many domestic systems are designed and assessed using simplified approaches that can be applied with little prior information. Oversimplification of the physical processes involved and ad hoc consideration of associated costs means that the results produced by these simplified methods are of questionable accuracy. This paper looks at three popular simplified approaches and compares the predicted water‐saving and financial performance with that of a more detailed simulation model, which includes explicit consideration of the physical processes and associated system costs. The simplified approaches predict significantly higher water and financial savings compared with the detailed model. Consequently it is recommended that simplified approaches should not be relied upon and greater preference should be given to the use of more detailed simulations that explicitly consider the important physical processes and include a thorough assessment of costs.     

Can project monitoring and control be fully automated?

An extended research programme has examined over the past two decades how productivity in construction projects can be improved through the development of models for project monitoring and control, which process automatically collected data on the actual project performance. Tests that were conducted with these models demonstrate that this approach can help overcome some of the limitations of existing manual methods. However, they also indicate that certain manually obtained data are still required in addition to the automatically collected data. A framework for semi-automated project monitoring and control is proposed, in which both manually and automatically collected data can be incorporated. This framework integrates the monitoring of projects with their control by taking into account the impact on productivity of existing deviations from the planned performance, and of the controlling actions that are proposed to deal with these deviations.     

Planning for Mixed Use: Affordable for Whom?

Problem, research strategy, and findings: Mixed-use zoning is widely advocated to increase density; promote active transportation; encourage economic development; and create lively, diverse neighborhoods. We know little, however, about whether mixed-use developments affect housing affordability. We question the impact of mixed-use zoning on housing affordability in Toronto (Canada) between 1991 and 2006 in the face of waning government support for affordable housing and increasing income inequality due to the occupational restructuring accompanying a shift to a knowledge-based economy. We fi nd that housing in mixed-use zones remained less affordable than housing in the rest of the city and in the metropolitan region. High-income service occupations experienced improved affordability while lower wage service, trade, and manufacturing occupations experienced stagnant or worsening affordability. Housing in mixed-use zones is increasingly affordable only to workers already able to pay higher housing costs. Our findings are limited to Canada's largest city but have lessons for large North American cities with similar urban economies and housing markets.

Takeaway for practice: Mixed-use developments may reduce housing affordability in core areas and inadvertently reinforce the sociospatial inequality resulting from occupational polarization unless supported by appropriate affordable housing policies. Planners should consider a range of policy measures to offset the unintentional outcomes of mixed-use developments and ensure affordability within mixed-use zones: inclusionary zoning, density bonuses linked to affordable housing, affordable housing trusts, and other relevant methods.     

Beyond the romantic and naı¨ve: the search for a complex ecological aesthetic design language for landscape architecture in New Zealand

Landscape design is an expression and repository of cultural values and beliefs, and in Aotearoa, New Zealand, the designed landscape faces particular challenges. Globalization is seen as a potential threat to landscape identity, which is even more significant for a country which has built its economy and self-image from its unique natural landscape. The potential for resistance is limited by the small size and youth of the profession of landscape architecture in New Zealand. While traditions of farming and gardening extend back to early European settlement in the mid nineteenth century, and beyond to indigenous Maori practices of land modification, professional landscape design is a relatively recent development (the first tertiary course in landscape architecture began at Lincoln College (now Lincoln University) in 1969). Landscape design in New Zealand draws its vocabulary from the power of the country's natural heritage landscapes, convinced that a naturalistic aesthetic exclusively represents environmental health. Some of the core values of New Zealand society are, however, overlooked by designers. The need to develop a critically informed design language which includes the farming landscape along with the natural one is argued. The invention of such a language, referred to as a complex ecological aesthetic, is seen as a potential source of design expression that is invigorated by the tension between mechanistic and natural landscape aesthetics. It therefore has the potential to promote environmental health, while being regionally grounded, and can help face the challenges that globilization poses to the landscape.     

What Is a Forecast for?

Abstract

Problem, research strategy, and findings: The forecasts transit agencies submit in support of applications for federal New Starts funding have historically overestimated ridership, as have ridership forecasts for rail projects in several countries and contexts. Forecast accuracy for New Starts projects has improved over time. Understanding the motivations of forecasters to produce accurate or biased forecasts can help forecast users determine whether to trust new forecasts. For this study I interviewed 13 transit professionals who have helped prepare or evaluate applications for federal New Starts funds. This sample includes interviewees who have had varying levels of involvement in all 82 New Starts projects that opened between 1976 and 2016. I recruited interviewees through a snowball sampling method; my interviews focus on the interviewees’ perspectives on how New Starts project evaluation and ridership forecasting has changed over time. Interview results suggest that ridership forecasters’ motivations to produce accurate forecasts may have increased with increased transparency, increased influence on local decision making, and decreased influence on external (federal) funding.

Takeaway for practice: Planners can evaluate the likely trustworthiness of forecasts based on transparency, internal influence, and external influence. If forecast users cannot easily determine a forecast’s key inputs and assumptions, if the forecaster has been tasked with producing a forecast to justify a predetermined action, and if an unfavorable forecast would circumvent decisions by the forecaster’s immediate client, forecasts should viewed with skepticism. Planners should seek to alter conditions that may create these conflicts of interest. Forecasters seem to be willing and able to improve forecast accuracy when the demand for accurate forecasts increases.     

Substrates for phosphorus removal-potential benefits for on-site wastewater treatment?

A large number of substrates potential for removal of phosphorus (P) in wastewater has been reviewed. The substrates consist of natural materials, industrial by-products and man-made products. Most substrates have been investigated in batch and column studies in the laboratory; others have also been tested in field trials. The results from these investigations vary, but a few substrates, e.g. wollastonite, slag material and, to some extent, light weight aggregate products, have demonstrated promising properties with regard to P-sorption capacity and hydraulics. The problems of normalisation of data are discussed, as well as the substrates potential benefits for on-site wastewater treatment.     

Trade Uber for the Bus?

Abstract

Problem, research strategy, and findings: Few studies have examined ride-hail users’ individual preferences between ride-hail and transit. Based on a survey of ride-hail users in the Philadelphia (PA) region, I examine who uses ride-hail and investigate ride-hail users’ willingness to use ride-hail versus transit. My results suggest that more than one-quarter of respondents replaced transit with ride-hail in their last ride-hail trips. Mixed logit regression analysis based on stated preference choice experiments indicate that higher-income respondents and respondents over 30?years old are increasingly willing to choose ride-hail over transit, even though their actual ride-hail usage is lower than that among lower-income and younger respondents. Results also show that female respondents are more willing to choose ride-hail over transit than male respondents and less frequent transit users are more likely to choose ride-hail than frequent transit users. Higher cost and longer trip duration are significant deterrents for travel by either mode. Respondents consider the time spent on walking to and from transit more burdensome than in-vehicle travel time and wait time for transit and ride-hail. They consider waiting for ride-hail less burdensome than waiting for transit. Survey sampling and design limitations provide lessons for future ride-hail studies.

Takeaway for practice: Practitioners should ensure convenient, affordable travel options for lower-income residents, who are more frequent but less willing ride-hail users than higher-income residents. Female respondents’ safety concerns about transit should urge transit agencies to recognize female transit riders’ travel needs. The relationship between age and willingness to use ride-hail reminds planners to anticipate greater substitution of ride-hail for transit as the more tech-savvy generation starts entering their 30s. Last, fare reduction alone may not be enough to prompt ride-hail users to switch to transit. Service improvements that shorten the overall trip duration are imperative to make transit more attractive.     

A Comparison of International Standards for the Beneficial Use of Biomaterials: Can We See Where We Might Be Going?

Stakeholder confidence, environmental protection, and due diligence are fundamental to the sustainable recycling of biosolids and other organic residuals. Open, independent, expert validation of recycling should be an important support to, and underpin, the entire process.
This paper (a) draws from information gathered during European Standards'work, and from other sources, to explore the consistencies and differences which exist between countries, (b) explores why some of these differences have arisen, (c) discusses the recommendations for future improvements, and (d) recommends that the recyclers of residuals should be more proactive in order to maximise their opportunity to influence and direct their destinies.     

The role of emotions on tourists’ willingness to pay for the Alpine landscape: a latent class approach

Previous research suggests that landscape preferences vary systematically amongst people. While various sources of heterogeneity have been considered in landscape preference literature, the role of emotions on willingness to pay for landscape features has never been examined. This article presents results of a choice experiment carried out for eliciting tourists’ for Alpine landscapes. The emotional state of respondents was used to model heterogeneity in a latent class approach. The study area is a valley in the Italian Alps, characterised by a strong importance of the primary sector and a low number of tourists. Landscape management could attract new visitors, providing additional income for the local inhabitants. Results indicate that respondents prefer a variegated and multi-faceted landscape, with a mix of tree species, several agricultural crops and open areas with grazing animals and that incidental emotions play a role in the construction of landscape preferences and influence willingness to pay.