A standardized cotton-strip assay for measuring organic-matter decomposition in streams

Assessment of stream ecosystem ‘health’ traditionally uses structural indicators (e.g., invertebrate community composition) but often neglects indicators of ecosystem processes (e.g., decomposition rates), providing an incomplete picture of overall ecosystem condition. Given a lack of standardized process-based indicators, we present a protocol for measuring organic-matter decomposition, represented by the breakdown of cellulose in the form of woven cotton fabric. The material, used more conventionally as artists’ fabric, has been suggested as a replacement for a standard cotton material (Shirley Burial Test Fabric) that had been widely used in decomposition studies for decades but is no longer manufactured. In field trials, we incubated cotton strips made of artists’ fabric in 49 streams in the Midwest (USA), northern Michigan (USA), and in New Zealand to: (1) test the assay under field conditions, (2) provide an initial population of data to which future studies can be compared, and (3) assess some environmental conditions that might influence cotton-strip decay. Decomposition of the strips, as loss of tensile strength, differed among regions and, in some cases, among streams within regions, suggesting that the assay is sensitive to differences in environmental conditions at regional and watershed scales. Mean rates (and standard deviation) of tensile-strength loss across streams of tensile-strength loss were 2.3%/d (0.4), 1.8%/d (0.7), and 1.5%/d (1.0) for the midwestern, Michigan, and New Zealand streams, and 1.7%/d (0.8) overall. Principal components analysis indicated that stream water ammonium and soluble reactive phosphorus explained a small but significant amount of variation (R² = 0.12) in tensile-strength loss among streams. Rates of respiration of cotton strips incubated in Michigan streams were positively related to tensile-strength loss (R² = 0.70). When streams were classified by substrate size, cotton-strip tensile strength (but not respiration) differed among substrate size classes. We conclude that a cotton-strip assay based on the artists’ fabric holds promise for replacing the assay based on the Shirley material, and as a process-based indicator for assessing the condition of stream ecosystems.     

Effect of hot-water extraction on alkaline pulping of bagasse

The effect of hot-water extraction on alkaline pulping was investigated. The properties of black liquor and pulp strength of bagasse were analyzed. The extraction was conducted at 160 °C for 30 min where 13.2% of the mass was dissolved in the extraction liquor. Untreated bagasse and extracted bagasse were digested by soda and soda-AQ processes at 17% and 15.5% (with 0.1% AQ) alkali charge (NaOH). Cooking temperatures were 160 °C and 155 °C respectively. The pulp from extracted bagasse had a lower Kappa number and a higher viscosity compared to the pulp from the untreated bagasse. The black liquor from pulping extracted bagasse had a lower solid content, a lower viscosity and a lower silica content, but a higher heating value than that from pulping of untreated bagasse. Hot-water extraction resulted in a significant decrease in bleaching chemical consumption and the formation of chlorinated organics. Pulp strength properties such as the tensile index and the burst index were found to be lower, but the tear index, bulk, opacity and pulp freeness were found to be higher when hot-water extraction was applied.     

Effect of microbial transglutaminase on dyeing properties of natural dyes on wool fabric

The dyeing properties of three natural dyes – curcumin, gardenia yellow and lac dye – on wool fabric after treatment with microbial transglutaminase (MTGase) have been investigated. After 120 min of MTGase treatment, compared with the fabric only pretreated with chemical and protease, the colour strength of curcumin, gardenia yellow and lac dye increased from 8±0.13, 7.5±0.10 and 22±0.12 to about 12.8±0.20, 11.7±0.20 and 27.0±0.41, respectively. The values of wash fastness for dyed wool fabrics increased from 2 to 4 after MTGase treatment, but the light fastness was not obviously improved. By comparing with mordant dyeing, although the colour strength was poorer, MTGase after-treatment did not cause colour shade changes during dyeing and the wash fastness of dyed wool fabric was similar to that of the pre-mordanted samples.     

Patch reef development in the florigemma-Bank Member (Oxfordian) from the Deister Mts (NW Germany): a type example for Late Jurassic coral thrombolite thickets

Small reefal bioconstructions that developed in lagoonal settings are widespread in a few horizons of the Late Jurassic (Oxfordian) succession of the Korallenoolith Formation, exposed southwest of Hannover, Northwest Germany. Especially the florigemma-Bank Member, “sandwiched” between oolite shoal deposits, exposes a high variety of build-ups, ranging from coral thrombolite patch reefs, to biostromes and to coral meadows. The reefs show a distribution with gradual facies variations along an outcrop belt that extends about 30 km from the Wesergebirge in the NW to the Osterwald Mts in the SE.The patch reefs from the Deister Mts locality at the “Speckhals” are developed as coral-chaetetid-solenoporid-microbialite reefs and represent a reef type that was hitherto unknown so far north of its Tethyan counterparts. They are mainly built up by coral thickets that are preserved in situ up to 1.5 m in height and a few metres in diameter. They contain up to 20 coral species of different morphotypes but are chiefly composed of phaceloid Stylosmilia corallina and Goniocora socialis subordinately. The tightly branched Stylosmilia colonies are stabilized by their anastomosing growth. The coral branches are coated with microbial crusts and micro-encrusters reinforcing the coral framework. Encrusters and other biota within the thicket show a typical community replacement sequence: Lithocodium aggregatum, Koskinobullina socialis and Iberopora bodeuri are pioneer organisms, whereas the occurrence of non-rigid sponges represents the terminal growth stage. The latter are preserved in situ and seem to be characteristic so far poorly known constituents of the Late Jurassic cryptobiont reef dweller community. The distance and overall arrangement of branches seems to be the crucial factor for the manifestation of a (cryptic) habitat promoting such community replacement sequences. Widely spaced branches often lack any encrusting and/or other reef dwelling organisms, whereas tightly branched corals, as is St. corallina, stimulate such biota. Hence, such reefs are well suited for research on coelobites and community sequences of encrusting and cavity dwelling organisms.     

Relationship of the urban fabric of Lawrence,Kansas with satellite-derived thermal infrared data

Many of the twelve land-use types and ten surface materials that comprise Lawrence, Kansas correlate significantly with afternoon and evening temperatures derived from thermal infrared data of the Heat Capacity Mapping Mission satellite. Three afternoon temperature patterns and six evening patterns were analyzed covering late spring through the middle of fall. Land uses account for a mean of 49% of the temperature variance in the daytime; the mean explained variance for the evening data is 37%. The temperature variation accounted for by surface materials is nearly the reverse of that of land use: the daytime and evening mean values are 32% and 49%, respectively. With the primary exception of trees, the correlations closely coincide with previously reported results relating the land uses and surface materials with temperatures for the city obtained from autotraverses.Abbreviations LST local standard time - CDT central daylight time     

An approach for vat color printing on cotton and polyester fabrics with electron beam irradiation curable formulations

Accelerated electrons delivered by electron beam accelerator were used to fix vat colors, incorporated in curable formulations containing diluting monomer and an oligomer, to cellulosic fabric, cotton and polyester fabric. Tetrahydrofurfuryl acrylate, hexane dioldiacrylate, monomers and trifunctional urethane methacrylate, oligomer were used as curable base beside ethylene glycol. The fabrics were printed with these formulations and exposed to various doses of electron beam irradiation generated from the 1.5 MeV (25 kW) electron beam accelerator machine. Critical factors included the irradiation dose, formulation composition, and vat color concentration were studied. The fabrics printed with the vat colors by electron beam irradiation displayed higher color yield than those fabrics printed by the conventional curing at equal vat color ratios. The durable properties of fabrics printed by electron beam irradiation except the roughness properties are extremely better than those printed by conventional fixation method.