Winter and Spring Thaw Measurements of N2O,NO and NOx Fluxes using a Micrometeorological Method

The impact of nitrogen fertilizers on gaseous emissions duringwinter and spring-thaw is not well understood and was the objective of this research. Using a micrometeorological method,N₂O, NO and NO_x fluxes from ryegrass were measured from November 1997 to March 1998. Three different mineralfertilizers were applied in November: urea (U), slow-release urea(SRU) and ammonium nitrate (AN). N₂O emissions during the winter were small, increasing significantly in March. Total losses of N₂O-N were significantly higher from SRU and U plots, with winter N₂O emissions accounting for 50% of annual losses. Nitric oxide fluxes from all plots weresmall during the measurement period (<0.9 ng N m^-2 s^-1). The NO fluxes from U and AN fertilized plots were significantly higher than from SRU and control plots. NO₂ fluxes were always negative (–6 ng N m^-2 s^-1)indicating deposition, but decreased to –2 ng N m^-2s^-1 when snow was present on the soil surface. Our resultsindicate that the form of inorganic N applied has an effect on NO+ N₂O emissions but not on NO₂ fluxes.Sponsored by CAPES – Brasília, Brazil     

The influence of social experience on cooperative behaviour of rats (Rattus norvegicus): direct vs generalised reciprocity

Cooperation among non-kin has been attributed sometimes to reciprocal altruism: Two or more individuals exchange behaviour that benefits the respective partner. According to direct reciprocity, cooperation is based on past behaviour of a known partner. In contrast, in generalised reciprocity, cooperation is based on anonymous social experience where the identity of the partner is irrelevant. In a previous study, female Norway rats (Rattus norvegicus) were found to cooperate according to a generalised reciprocity mechanism. In this study, we tested whether Norway rats would also cooperate as predicted by a direct reciprocity mechanism and whether direct reciprocity would cause a higher propensity to cooperate than generalised reciprocity. Focal animals were experimentally manipulated to receive social experience from known or unknown, helpful or defecting partners in an instrumental cooperative task. Our first experiment shows that rats are more helpful towards a partner from which they had received help before than towards a partner that had not helped (i.e. direct reciprocity). Our second experiment revealed that after receiving help by others, rats were more helpful towards a partner from which they had received help before than towards a new partner (i.e. direct reciprocity generated a higher cooperation propensity than generalised reciprocity). We conclude that in female Norway rats, the tendency to cooperate is influenced by partner-specific information. To our knowledge, this is the first study to demonstrate direct reciprocity in rodents, and it is the first study testing direct vs generalised reciprocity in animals.     

The influence of technological innovation and human capital on environmental efficiency among different regions in Asia-Pacific

Environmental Science and Pollution Research - This study employs super-efficiency DEA model with desirable inputs and an undesirable output in calculating environmental efficiency values in...     

Is micronucleus assay in oral exfoliated cells a suitable tool for biomonitoring children exposed to environmental pollutants? A systematic review

Environmental Science and Pollution Research - The aim of this review was to evaluate if micronucleus assay in oral exfoliated cells is a suitable tool for biomonitoring children exposed to...     

Microbial Source Tracking Analysis Using Viral Indicators in Santa Lucía and Uruguay Rivers,Uruguay

The aim of this study was to determine the origin (human, bovine or porcine) and the concentration of the fecal sources of contamination in waters from Santa Lucía basin and Uruguay River in Uruguay by using host-specific viral markers (adenoviruses and polyomaviruses) as microbial source tracking (MST). Between June 2015 and May 2016, monthly collections of surface water samples were performed in six sites in Santa Lucía basin and four sites in Uruguay River (n = 120 samples). Viral concentration was carried out using an absorption-elution method. Detection and quantification of human and porcine adenovirus (HAdV and PAdV, respectively) and human and bovine polyomavirus (HPyV and BoPyV, respectively) were performed by quantitative PCR (qPCR). To evaluate the infectivity of circulating HAdV, an integrated cell culture-qPCR (ICC-qPCR) was used. A logistic regression analysis was carried out to estimate the influence of environmental variables on the virus presence in surface waters. Overall, HAdV was the prevalent (18%; 21/120) followed by BoPyV (11%; 13/120) and HPyV (3%; 3/120), whereas PAdV was not detected in this study. The mean concentration ranged from 1.5 × 10⁴ genomic copies/L (gc/L) for HAdV to 1.8 × 10² gc/L for HPyV. Infective HAdVs were observed in two out of ten analyzed samples. A significant effect of environmental temperature (p = 0.001) and river (p = 0.012) on the presence of human viruses was found. These results suggest that fecal contamination could affect the water quality of these rivers, showing deficiencies in the procedure of sewage discharge from regional cities, livestock and dairy farms.

     

Prediction of Musculoskeletal Discomfort in a Pick and Place Task (A pilot study)

A pilot study was conducted regarding the effects of working posture, handling frequency, and task duration on musculoskeletal discomfort. Participants rated their discomfort perceived while performing a repetitive task at 8 different combinations of manipulations. Pauses between the work periods lasted 15 min. Discomfort was rated according to Borg’s category-ratio scale CR-10 and postures were recorded by an optoelectronic movement registration system. From linear multiple regression analysis equations for predicting discomfort at various body regions were obtained. Coefficients of determination especially point to trunk inclination and handling frequency as major determinants of musculoskeletal discomfort.     

Queue up, please! Spermathecal filling in the rove beetle Drusilla canaliculata (Coleoptera, Staphylinidae)

Most studies on insect sperm motility have been conducted in vitro using artificial environments outside the animal’s body. Only little is known about the function of motile insect sperm at different sites within the male or female genital tracts. We dissected genital tracts of female rove beetles (Drusilla canaliculata) to show that spermatozoa use their own motility to migrate from the spermatophore into the spermatheca. Our dissection method allowed direct observation and filming of the spermathecal filling process inside the female’s genital tract. Spermatozoa were found to enter the spermatheca individually, sometimes in groups of two or three. Although exhibiting only weak motility and no progressive motion in buffer solution, the spermatozoa inside the female show vigorous lashing and reach an average velocity of 47.5 μm s⁻¹. To gain mobility and speed, the spermatozoa likely utilize the relatively small diameter of the spermathecal duct to push themselves off the duct walls, rather than swimming freely in seminal fluid. The spermatozoa (approximately 1,250 μm) are considerably longer than the distance they have to travel along the spermathecal duct (approximately 800 μm). Our study provides the first direct observation of active sperm migration within the female of an insect stressing the importance of the genital tract as a prerequisite for functional sperm motility.     

Requirements for adaptive governance of groundwater ecosystem services: insights from Sandveld (South Africa), Upper Guadiana (Spain) and Spree (Germany)

The over-abstraction of aquifers and the modification of landscape–water systems often result in the degradation of groundwater resources and the loss of related ecosystem services. Many of these problems are associated with failure of governance and management regimes. Thus, groundwater resources require innovative approaches that deal with system complexity moving governments toward adaptive and integrated management. Vertical (hierarchical) and horizontal (cross-sectoral) integration structures are crucial characteristics of adaptive governance and support sustainable management of groundwater ecosystem services. The research objective of this article is to investigate linkages between these integration structures, the governance regime and the state of groundwater ecosystem services across three case studies: Sandveld (South Africa), Upper Guadiana (Spain) and Spree (Germany). First, we developed a set of criteria indicating vertical and horizontal integration and then applied a conceptual and analytical approach, the Management and Transition Framework, specifically developed to support a systematic and consistent investigation of policy and management processes. Results indicate that higher degrees of integration during management activities do not identify a direct improvement of groundwater ecosystem services. But evidence highlights that integration (1) opens up the political arena for environmental perspectives, (2) increases the quality of groundwater and conservation plans, (3) accelerates the implementation of policies, (4) mitigates conflicts between different groundwater users and (5) increases the awareness of different ecosystem services. Finally, we conclude that compared with other natural resources, groundwater management still lacks participation, multi-level interactions and sectoral integration, especially at higher levels of management.