Are chaos and catastrophe theories relevant to environmental sciences?

Data acquired in the area of Environmental Sciences are by their very nature often discontinuous and abrupt. As such, the mathematical theories of catastrophe and chaos may be of use in analyzing such scientific data and in formulating mathematical models.     

Ultrasonic placental localization in relation to spontaneous abortion after mid-trimester amniocentesis

This paper summarizes our experience with a series of 562 women referred for mid-trimester amniocentesis for prenatal diagnosis. Ultrasonography was utilized for placental localization. Follow-up revealed a fetal loss rate of 3.03 per cent with 1.96 per cent being spontaneous abortions. Patients with an anterior placenta had a fetal loss and spontaneous abortion rate of 4.06 per cent and 3·05 per cent, respectively. No significant difference in the incidence of fetal loss (p > 0·1) or spontaneous abortion (p > 0·5) was found in patients having an anterior versus a posterior placenta. Neither multiple insertions through an anterior placenta nor blood contaminated amniotic fluid from patients with an anterior placenta were associated with an increased incidence of fetal loss or spontaneous abortion.     

Diets of four decapod crustaceans (Linuparus trigonus,Metanephrops andamanicus,M. australiensis and M. boschmai) from the continental shelf around Australia

Linuparus trigonus (Palinuridae) was collected from northeast Australia at depths of 220 to 300 m in the austral summer of 1985–1986 and its diet was analysed for diel feeding-periodicity and composition. The sex and size of the lobsters and the depth at which they were caught were recorded. About 35% of the foreguts were less than 10% full. L. trigonus appears to be a predator of slow-moving or nearsessile benthic invertebrates; its diet is mainly bivalves, gastropods, ophiuroids, crustaceans, polychaetes, and foraminiferans. Most dietary items differed significantly between the size classes of lobster. The frequency of crustacean remains increased with depth and more gastropods were consumed by lobsters caught at 260 m than at other depths. No significant periodicity in feeding was found for L. trigonus. The foreguts of three Metanephrops spp. (Nephropidae) collected from north-west Australia in August 1983 (M. andamanicus) and January/February 1984 (M. australiensis and M. boschmai) were nearly empty, and nearly half were less than 10% full. Fish, crustaceans and squids were the most common food items eaten. The main food items varied between the species: M. andamanicus ate nearly equal amounts of fish and crustaceans; M. australiensis ate chiefly crustaceans; M. boschmai mainly ate fish and seldom fed on squid. Metanephrops spp. appear to feed by attacking mobile animals and tearing off appendages or by scavenging.     

Multiplexed species-specific PCR protocol to discriminate four N. Atlantic Calanus species, with an mtCOI gene tree for ten Calanus species

Accurate species identification is the cornerstone of any ecological study - yet this fundamental step is not always possible for marine zooplankton. Routine species' identification, especially of juvenile andlarval stages, is difficult for Calanus species (Copepoda; Calanoida) in the N. Atlantic Ocean, where two or three species may co-occur. A rapid, simple, and inexpensive molecularly based protocol to identify individual copepods of any life stage has beendeveloped. This protocol will routinely identify four Calanus species in the N. Atlantic and will help to accurately understand the role of each species in coastal and open ocean ecosystems. The DNA sequence of a 633 bp region of the mitochondrial cytochrome oxidase I (mtCOI) was determined for ten Calanus species: C. australis (Brodsky, 1959), C. chilensis (Brodsky, 1959), C. finmarchicus (Gunnerus, 1770), C. glacialis (Jaschnov, 1955), C. helgolandicus (Claus, 1863), C. hyperboreus (Krøyer, 1838), C. marshallae (Frost, 1974), C. pacificus (Brodsky, 1948), C. simillimus (Giesbrecht, 1902), and C. sinicus (Brodsky, 1965). MtCOI sequences were used to design species-specific oligonucleotide primers for C. finmarchicus, C. glacialis, C. helgolandicus, and C. hyperboreus and to optimize a competitive, multiplexed, species-specific PCR (SS-PCR) protocol to discriminate the four species. This corrects and improves a previously published protocol for three Calanus species (Bucklin et al. 1999: Hydrobiologia 401:239-254), unambiguously identifying individual copepods and copepodites from diverse geographic regions of the four species' ranges. In order to further examine the pattern of mtCOI evolution within Calanus (an important consideration for molecular systematic characters), consensus mtCOI sequences were used to reconstruct phylogenetic relationships among the ten species; the mtCOI gene tree agreed with morphological and molecular (based on mt16S rRNA) phylogenies, except that the affiliation of C. sinicus could not be resolved.     

PSII activity and pigment dynamics of Symbiodinium in two Indo-Pacific corals exposed to short-term high-light stress

This study examined the capacity for photoprotection and repair of photo-inactivated photosystem II in the same Symbiodinium clade associated with two coexisting coral species during high-light stress in order to test for the modulation of the symbiont’s photobiological response by the coral host. After 4 days exposure to in situ irradiance, symbionts of the bleaching-sensitive Pocillopora damicornis showed rapid synthesis of photoprotective pigments (by 44 %) and strongly enhanced rates of xanthophyll cycling (by 446 %) while being insufficient to prevent photoinhibition (sustained loss in F _v/F _m at night) and loss of symbionts after 4 days. By contrast, Pavona decussata showed no significant changes in F _v/F _m, symbiont density or xanthophyll cycling. Given the association with the same Symbiodinium clade in both coral species, our findings suggest that symbionts in the two species examined may experience different in hospite light conditions as a result of different biometric properties of the coral host.     

Evaluation of Solvita compost stability and maturity tests for assessment of quality of end-products from mixed latrine style compost toilets

It is challenging and expensive to monitor and test decentralized composting toilet systems, yet critical to prevent the mismanagement of potentially harmful and pathogenic end-product. Recent studies indicate that mixed latrine composting toilets can be inhibited by high ammonia content, a product of urea hydrolysis. Urine-diverting vermicomposting toilets are better able to accomplish the goals of remote site human waste management by facilitating the consumption of fecal matter by earthworms, which are highly sensitive to ammonia. The reliability of Solvita® compost stability and maturity tests were evaluated as a means of determining feedstock suitability for vermicomposting (ammonia) and end-product stability/completeness (carbon dioxide). A significant linear regression between Solvita® ammonia and free ammonia gas was found. Solvita® ranking of maturity did not correspond to ranking assigned by ammonium:nitrate standards. Solvita® ammonia values 4 and 5 contained ammonia levels below earthworm toxicity limits in 80% and 100% of samples respectively indicative of their use in evaluating feedstock suitability for vermicomposting. Solvita® stability tests did not correlate with carbon dioxide evolution tests nor ranking of stability by the same test, presumably due to in situ inhibition of decomposition and microbial respiration by ammonia which were reported by the Solvita® CO₂ test as having high stability values.     

On‐target deposition of aerially applied deltamethrin

Abstract

The mean amount of deltamethrin deposited on natural substrates (i.e., soil and vegetation) in three experiments was 63, 73, and 76% of applied. Composite samples taken from 16 sites/replicate gave representative and repeatable measures of deposition. The use of Teflon discs as artificial targets to measure aerial deposition was investigated. The discs had only 34–71% mean trapping efficiency for the spray droplets. Deposition was quite variable among different sampling sites within a field (CV=73–83%). Much of this variation was caused by irregular overlapping of spray swaths.     

An integrated appraisal of energy recovery options in the United Kingdom using solid recovered fuel derived from municipal solid waste

This paper reports an integrated appraisal of options for utilising solid recovered fuels (SRF) (derived from municipal solid waste, MSW) in energy intensive industries within the United Kingdom (UK). Four potential co-combustion scenarios have been identified following discussions with industry stakeholders. These scenarios have been evaluated using (a) an existing energy and mass flow framework model, (b) a semi-quantitative risk analysis, (c) an environmental assessment and (d) a financial assessment. A summary of results from these evaluations for the four different scenarios is presented. For the given ranges of assumptions; SRF co-combustion with coal in cement kilns was found to be the optimal scenario followed by co-combustion of SRF in coal-fired power plants. The biogenic fraction in SRF (ca. 70%) reduces greenhouse gas (GHG) emissions significantly (～2500 g CO₂ eqvt./kg DS SRF in co-fired cement kilns and ～1500 g CO₂ eqvt./kg DS SRF in co-fired power plants). Potential reductions in electricity or heat production occurred through using a lower calorific value (CV) fuel. This could be compensated for by savings in fuel costs (from SRF having a gate fee) and grants aimed at reducing GHG emission to encourage the use of fuels with high biomass fractions. Total revenues generated from coal-fired power plants appear to be the highest (£95/t SRF) from the four scenarios. However overall, cement kilns appear to be the best option due to the low technological risks, environmental emissions and fuel cost. Additionally, cement kiln operators have good experience of handling waste derived fuels. The scenarios involving co-combustion of SRF with MSW and biomass were less favourable due to higher environmental risks and technical issues.     

Zonal management of arsenic contaminated ground water in Northwestern Bangladesh

This paper used ordinary kriging to spatially map arsenic contamination in shallow aquifers of Northwestern Bangladesh (total area  35,000 km²). The Northwestern region was selected because it represents a relatively safer source of large-scale and affordable water supply for the rest of Bangladesh currently faced with extensive arsenic contamination in drinking water (such as the Southern regions). Hence, the work appropriately explored sustainability issues by building upon a previously published study (Hossain et al., 2007; Water Resources Management, vol. 21: 1245–1261) where a more general nation-wide assessment afforded by kriging was identified. The arsenic database for reference comprised the nation-wide survey (of 3534 drinking wells) completed in 1999 by the British Geological Survey (BGS) in collaboration with the Department of Public Health Engineering (DPHE) of Bangladesh. Randomly sampled networks of zones from this reference database were used to develop an empirical variogram and develop maps of zonal arsenic concentration for the Northwestern region. The remaining non-sampled zones from the reference database were used to assess the accuracy of the kriged maps. Two additional criteria were explored: (1) the ability of geostatistical interpolators such as kriging to extrapolate information on spatial structure of arsenic contamination beyond small-scale exploratory domains; (2) the impact of a priori knowledge of anisotropic variability on the effectiveness of geostatistically based management. On the average, the kriging method was found to have a 90% probability of successful prediction of safe zones according to the WHO safe limit of 10 ppb while for the Bangladesh safe limit of 50 ppb, the safe zone prediction probability was 97%. Compared to the previous study by Hossain et al. (2007) over the rest of the contaminated country side, the probability of successful detection of safe zones in the Northwest is observed to be about 25% higher. An a priori knowledge of anisotropy was found to have inconclusive impact on the effectiveness of kriging. It was, however, hypothesized that a preferential sampling strategy that honored anisotropy could be necessary to reach a more definitive conclusion in regards to this issue.