Open Corridors Appear to Facilitate Dispersal by Ringlet Butterflies (Aphantopus hyperantus) between Woodland Clearings

We studied the ringlet butterfly (Aphantopus hyperantus) in an area of woodland in eastern England. A. hyperantus occurs in open fields, rides (grassy tracks), and glades within the woodland. Mark-recapture methods showed that exchange rates of adult A. hyperantus between fields and glades can be predicted better by distance-via-rides than by direct distance. Behavioral observations showed that A. hyperantus readily moved from glades into rides but rarely moved from glades into dense woodland. The rides are likely to be corridors that act as conduits between fields and glades. In the A. hyperantus system, connectivity could reduce local extinctions and increase rates of recolonization in the event of local extinction.     

A mesocosm approach for detecting stream invertebrate community responses to treated wastewater effluent

The discharge of wastewater from sewage treatment plants is one of the most common forms of pollution to river ecosystems, yet the effects on aquatic invertebrate assemblages have not been investigated in a controlled experimental setting. Here, we use a mesocosm approach to evaluate community responses to exposure to different concentrations of treated wastewater effluents over a two week period. Multivariate analysis using Principal Response Curves indicated a clear, dose-effect response to the treatments, with significant changes in macroinvertebrate assemblages after one week when exposed to 30% effluent, and after two weeks in the 15% and 30% effluent treatments. Treatments were associated with an increase in nutrient concentrations (ammonium, sulfate, and phosphate) and reduction of dissolved oxygen. These findings indicate that exposure to wastewater effluent cause significant changes in abundance and composition of macroinvertebrate taxa and that effluent concentration as low as 5% can have detectable ecological effects.     

Factors influencing appropriate management of household hazardous waste in Nakhon Nayok,Thailand: A multilevel analysis

Household hazardous products contain hazardous chemicals, so when discarding these products a household hazardous waste (HHW) stream is created. HHW is a major environmental problem in Thailand, yet HHW has received scant attention so management is often inadequate or inappropriate. The objective of this study was to investigate the factors associated with appropriate HHW management in Thailand. Data were collected using a structured questionnaire completed during randomly assigned household interviews in Nakhon Nayok province, Thailand, between February and May 2017. The proportion of “appropriate management” was presented as percentage with its 95% confidence interval (CI). A multilevel mixed-effects logistic regression model was performed to determine the factors associated with appropriate HHW management, with 663 households included. The proportion of appropriate HHW management was 23.4% (95%CI: 20.2% to 26.6%). Both individual and local government administrative organization factors had on an effect on appropriate HHW management, including (a) being female (adjusted odds ratio [OR]:1.59; 95%CI: 1.03 to 2.46); (b) household size (adjusted OR: 1.66; 95%CI: 1.09 to 2.54); (c) knowledge score vis-à-vis HHW management (adjusted OR: 1.78; 95%CI: 1.43 to 2.02); (d) appropriate HHW storage behavior (adjusted OR: 2.48; 95%CI: 1.60 to 3.83); and (e) appropriate HHW use behavior (adjusted OR: 3.97; 95%CI: 2.40 to 6.58). The government of Thailand might consider a program to increase appropriate management of household hazardous waste to mitigate public health and environmental contamination risks.

Implications: Household hazardous waste becomes a major concern in many countries, including Thailand. The household hazardous waste management should be started at the source first, because household hazardous waste is mixed with the municipal waste stream. Thus, this study finding will be important for policymakers such as government and local government and can be used to create a specific policy and campaigns for household hazardous waste management.     

Evaluation of spatial and temporal variations in marine sediments quality using multivariate statistical techniques

Spatial and temporal variations of sediment quality in Matanzas Bay (Cuba) were studied by determining a total of 12 variables (Zn, Cu, Pb, As, Ni, Co, Al, Fe, Mn, V, CO₃ ^2?, and total hydrocarbons (THC). Surface sediments were collected, annually, at eight stations during 2005–2008. Multivariate statistical techniques, such as principal component (PCA), cluster (CA), and lineal discriminant (LDA) analyses were applied for identification of the most significant variables influencing the environmental quality of sediments. Heavy metals (Zn, Cu, Pb, V, and As) and THC were the most significant species contributing to sediment quality variations during the sampling period. Concentrations of V and As were determined in sediments of this ecosystem for the first time. The variation of sediment environmental quality with the sampling period and the differentiation of samples in three groups along the bay were obtained. The usefulness of the multivariate statistical techniques employed for the environmental interpretation of a limited dataset was confirmed.     

Ecological profiles of caddisfly larvae in Mediterranean streams: implications for bioassessment methods

Caddisflies are a well represented group with high species diversity in Mediterranean climate rivers. Although they are widely used in water quality assessment, little is known of the ecological profiles of families or species. We present a simple score for ecological profiles which measures intolerance to water quality. The ecological profiles of caddisflies are diverse and the degree of tolerance at the family level is related to species diversity and the tolerance of individual species to water quality. Comparisons with the scores used in the biotic index IBMWP show general agreement between the degree of intolerance of a family and its score in the IBMWP, with few exceptions. Studies on tolerance are required to elucidate the autecology of taxa, and to develop biological indices, especially in areas with high species diversity.