ECONOMIC FRAMEWORK FOR FLOOD AND SEDIMENT CONTROL WITH DETENTION BASINS1

ABSTRACT: A framework for combining economic factors and the hydrolo of detention basins is provided. The general development of economic production functions for water quality (sediment) and flood control is discussed. Example production functions are generated to compare water quality (sediment control only) and flood control. For the given example, the design of a detention basin for downstream sediment control is economically unwarranted. When compared to on-site detention facilities, regional detention structures appear to be more practical from an economic standpoint for water quality control. Since sediment was the only water quality parameter assessed, it is entirely possible that the design of a detention basin for water quality control would be justified if the effects of all pollutants of concern could be quantified. Policy aspects of detention facilities that relate to the economics of water quality control are also discussed.     

Incorporating soil structure and root distribution into plant uptake models for radionuclides: toward a more physically based transfer model

Most biosphere and contamination assessment models are based on uniform soil conditions, since single coefficients are used to describe the transfer of contaminants to the plant. Indeed, physical and chemical characteristics and root distribution are highly variable in the soil profile. These parameters have to be considered in the formulation of a more realistic soil-plant transfer model for naturally structured soils. The impact of monolith soil structure (repacked and structured) on Zn and Mn uptake by wheat was studied in a controlled tracer application (dye and radioactive) experiment. We used Brilliant Blue and Sulforhodamine B to dye flow lines and 65Zn and 54Mn to trace soil distribution and plant uptake of surface-applied particle-reactive contaminants. Spatial variation of the soil water content during irrigation and plant growth informs indirectly about tracer and root location in the soil profile. In the structured monolith, a till pan at a depth of 30 cm limited vertical water flow and root penetration into deeper soil layers and restricted tracers to the upper third of the monolith. In the repacked monolith, roots were observed at all depths and fingering flow allowed for the fast appearance of all tracers in the outflow. These differences between the two monoliths are reflected by significantly higher 54Mn and 65Zn uptake in wheat grown on the structured monolith. The higher uptake of Mn can be modelled on the basis of radionuclide and root distribution as a function of depth and using a combination of preferential flow and rooting. The considerably higher uptake of Zn requires transfer factors which account for variable biochemical uptake as a function of location.     

The oldest European fossil songbird from the early Oligocene of Germany

We report on the oldest European songbird (Passeriformes), from the early Oligocene (30–34 million years ago) of Frauenweiler in Germany. The specimen represents the earliest associated remains of an early Tertiary passerine described so far. It ties the first appearance of Passeriformes in Europe to a minimum age of 30 million years. Passeriform birds are absent in Eocene deposits that yielded abundant remains of small land birds and apparently dispersed into Europe around the Eocene/Oligocene boundary (about 34 million years ago), not at the Oligocene/Miocene boundary (about 24 mya) as hitherto thought. This possibly relates the appearance of songbirds in Europe to a well-known major faunistic break at the Eocene/Oligocene boundary, called the grande coupure. The Frauenweiler songbird most notably differs from extant Passeriformes in having a larger processus procoracoideus on the coracoid and appears to be outside Eupasseres, the taxon which includes Oscines (all modern European and most Old World songbirds) and Suboscines (most South and Central American songbirds). It shows that there were earlier dispersal events of non-oscine songbirds into Europe before the arrival of Oscines from the Australian continental plate towards the late Oligocene.     

Mechanical Property and Biodegradability of Cast Films Prepared from Blends of Oppositely Charged Biopolymers

Biodegradable cast films of about 50 m thickness were fabricated by blending oppositely charged biopolymers such as anionic starch–chitosan, and cationic starch–pectin. The tensile strength and elongation at break (%) of films were evaluated as well as their capacity to degrade in compost. Films recovered from soil every 48 h showed consistent degradation (weight loss), diminution of the polymers characteristic peak absorbance in the carbohydrate fingerprint region of the FTIR, and changes in the surface morphology via scanning electron microscopy (SEM). Anionic starch–chitosan films had much superior tensile strength and elongation compared to cationic starch–pectin, suggesting that the ionic bonds formed between anionic-starch and positively charged groups in chitosan polymer were much more stable and stronger. Initially, both films lost about 36% weight within 96 h, which also correlated well with the loss in the characteristic absorption peaks in the region of the infrared spectrum typical of biopolymers. The total mineralization of films by microorganisms in compost soil was also measured using respirometric techniques. Though the rate of mineralization differed for two formulations, total mineralization (extent) for both films were achieved within 45 days.     

Revegetation of an abandoned uranium millsite on the Colorado Plateau, Arizona

We attempted to restore native plants on disturbed sites at a former uranium mill on the Colorado Plateau near Tuba City, AZ. Four-wing saltbush [Atriplex canescens (Pursh) Nutt.] was successfully established in compacted caliche soil and in unconsolidated dune soil when transplants were irrigated through the first summer with 20 L/plant/wk. The caliche soil was ripped before planting to improve water-holding capacity. The diploid saltbush variety, angustifolia, had higher survival and growth than the common tetraploid variety, occidentalis, especially on dune soil. The angustifolia variety grew to 0.3 to 0.4 m3 per plant over 3 yr even though irrigation was provided only during the establishment year. By contrast, direct seeding of a variety of native forbs, grasses, and shrubs yielded poor results, despite supplemental irrigation throughout the first summer. In this arid environment (precipitation = 100 to 200 mm/yr), the most effective revegetation strategy is to establish keystone native shrubs, such as four-wing saltbush, using transplants and irrigation during the establishment year, rather than attempting to establish a diverse plant community all at once.     

The influence of estuarine water quality on cover of barnacles and Enteromorpha spp.

The influence of ambient water quality on the settlement of barnacles and the green alga Enteromorpha spp. to an artificial substratum in the estuaries of Sydney, Australia, was investigated to test the efficacy of both groups of organisms as indicators of changes in water quality due to urban stormwater runoff and/or sewage overflows. Wooden settlement panels were immersed for 4 months on 17 occasions between 1996 and 2005 at 11 locations known to vary in water-quality parameters (conductivity, total uncombined ammonia, oxidised nitrogen, total nitrogen, filterable phosphorus, total phosphorus, faecal coliforms and chlorophyll-a) and ambient meteorological conditions (total rainfall, maximum rainfall). Water-quality data were collected during the time that the settlement panels were deployed. Cover of barnacles was highly variable among locations (range 1.2?C55.2%). Hierarchical partitioning found that chlorophyll-a, total phosphorus and total nitrogen had significant independent positive effects on barnacle cover. Together, these variables explained 26% of the variation in barnacle cover. Mean cover of Enteromorpha spp., however, did not vary significantly among locations suggesting that other potentially more important factors are influencing its settlement and growth. The results of this study suggest that barnacle cover is likely to be a useful indicator of some components of water quality.     

(Re-)producing bioassemblages: positionalities of regional bioeconomy development in Finland

ABSTRACT

Bioeconomy is a new political and economic buzzword that frames many proposed pathways to sustainable regional development in Europe, particularly in rural, biomass rich areas. Dissected by research into various strands, visions, shades of “green” and presented by bioeconomy stakeholders through regional examples and self-promoting bio-clusters, the socio-spatial processes of regional assemblages are often ignored in these accounts. Based on a prominent Finnish example, this case study employs the concept of bioassemblage to display the socio-spatial positionalities of regional bioeconomy development in the places of materialisation. Furthermore, it ties the spatial (re-)production of bioassemblages to their role as bioeconomy policy translation loops and consequently provides insights into the processes of bioeconomy policy mobility, translation and mutation. Examining the positionalities in a bioassemblage presents a complex and frequently shifting local environment accompanied by unequal power topologies and means of territorialisation. Shallow policy narratives create problematic mismatches between the “best-practices” employed by policy makers and regional bioeconomy materialisation in the places themselves. While the study makes no assumption on the sustained future of bioeconomy development, it shows that current processes enable the externalisation of risks at industrial sites, restrict wider participation and discredit the important role of institutional actors in development.