Nitrogen removal from urban stormwater runoff through layered bioretention columns.

Bioretention is a low-impact technology used for the treatment of stormwater runoff in developed areas. The fates of mineral nitrogen compounds in two bioretention columns (RP1 and RP2) with different media-layering characteristics were investigated under multiple loadings of simulated urban runoff. The immediate capture of nitrogen was evaluated, with nitrogen transformation reactions that occurred during the drying periods between rainfall events. A greater proportion of ammonium was removed from runoff in RP2 (68 +/- 16%), which had a high permeability layer over a lower permeability layer, than in RP1 (12 +/- 6%), which had the inverse configuration. Both column systems demonstrated nitrate export (9 +/- 32% and 54 +/- 22% greater than input for RP1 and RP2, respectively), attributed to washout of nitrate resulting from nitrification processes between runoff loading events. Bioretention media with a less permeable bottom soil layer could form an anoxic/anaerobic zone for promoting nitrification/denitrification processes.     

Male aggression varies with consortship rate and habitat in a dolphin social network

Behavioral Ecology and Sociobiology - In many species, outcomes of male duels determine access to females and, ultimately, male reproductive success. Ritualization of behavior in male contests can...     

Initial progress in implementing the Sustainable Development Goals (SDGs): a review of evidence from countries

The global Sustainable Development Goals (SDGs) commenced in 2016 and provide an evidence-based framework for sustainable development planning and programming until 2030. There is emerging international practice and a growing catalogue of related reviews, assessments, guidelines and publications. While the expert community is clearly emphasising the need to adopt evidence- and science-based approaches to SDG implementation, policymakers now face the challenge of implementing the SDGs simultaneously in a coherent and integrated manner. Regular systematic reviews of national progress and approaches to implementing the SDGs are advisable to ensure that emerging science and knowledge is effectively informing national practice. This paper reviews the recent academic and expert literature as well as national experience in implementing the SDGs in 26 countries. It uses a systematic approach to analyse the degree to which key implementation stages and approaches recommended in the expert literature are being adopted and applied to support national SDG implementation on-the-ground. The review highlights that while progress has been made in some initial planning stages, key gaps remain in terms of the assessment of interlinkages, trade-offs and synergies between targets. Gaps are also clearly evident in the adoption of systems thinking and integrated analytical approaches and models. This is problematic as it may undermine effective implementation and the transformative potential of the SDGs. As more countries turn their attention to the SDGs, the review underscores the considerable risk that they will pursue the same ‘siloed’ or ‘linear’ approaches to sustainable development that have met with limited success in the past.     

The perpetual state of emergency that sacrifices protected areas in a changing climate

A modern challenge for conservation biology is to assess the consequences of policies that adhere to assumptions of stationarity (e.g., historic norms) in an era of global environmental change. Such policies may result in unexpected and surprising levels of mitigation given future climate‐change trajectories, especially as agriculture looks to protected areas to buffer against production losses during periods of environmental extremes. We assessed the potential impact of climate‐change scenarios on the rates at which grasslands enrolled in the Conservation Reserve Program (CRP) are authorized for emergency harvesting (i.e., biomass removal) for agricultural use, which can occur when precipitation for the previous 4 months is below 40% of the normal or historical mean precipitation for that 4‐month period. We developed and analyzed scenarios under the condition that policy will continue to operate under assumptions of stationarity, thereby authorizing emergency biomass harvesting solely as a function of precipitation departure from historic norms. Model projections showed the historical likelihood of authorizing emergency biomass harvesting in any given year in the northern Great Plains was 33.28% based on long‐term weather records. Emergency biomass harvesting became the norm (>50% of years) in the scenario that reflected continued increases in emissions and a decrease in growing‐season precipitation, and areas in the Great Plains with higher historical mean annual rainfall were disproportionately affected and were subject to a greater increase in emergency biomass removal. Emergency biomass harvesting decreased only in the scenario with rapid reductions in emissions. Our scenario‐impact analysis indicated that biomass from lands enrolled in the CRP would be used primarily as a buffer for agriculture in an era of climatic change unless policy guidelines are adapted or climate‐change projections significantly depart from the current consensus.     

Total organic halogen (TOX) in human urine: A halogen-specific method for human exposure studies

Disinfection by-products(DBPs) are a complex mixture of compounds unintentionally formed as a result of disinfection processes used to treat drinking water. Effects of long-term exposure to DBPs are mostly unknown and were the subject of recent epidemiological studies. However,most bioanalytical methods focus on a select few DBPs. In this study, a new comprehensive bioanalytical method has been developed that can quantify mixtures of organic halogenated compounds, including DBPs, in human urine as total organic chlorine(TOCl), total organic bromine(TOBr), and total organic iodine(TOI). The optimized method consists of urine dilution, adsorption to activated carbon, pyrolysis of activated carbon, absorption of gases in an aqueous solution, and halide analysis with ion chromatography and inductively coupled plasma-mass spectrometry. Spike recoveries for TOCl, TOBr, and TOI measurements ranged between 78% and 99%. Average TOCl, TOBr, and TOI concentrations in five urine samples from volunteers who consumed tap water were 1850, 82, and 21.0 μg/L as X~-, respectively.Volunteers who consumed spring water(control) had TOCl, TOBr, and TOI average concentrations in urine of 1090, 88, and 10.3 μg/L as X~-, respectively. TOCl and TOI in the urine samples from tap water consumers were higher than the control. However, TOBr was slightly lower in tap water urine samples compared to mineral water urine samples, indicating other sources of environmental exposure other than drinking water. A larger sample population that consumes tap water from different cities and mineral water is needed to determine TOCl, TOBr, and TOI exposure from drinking water.     

Ontogeny of fetal liver glucose-6-phosphatase activity

A reliable and sensitive microassay for the measurement of liver glucose-6-phosphatase is described. Human fetal liver was assayed for glucose-6-phosphatase activity from 7.5 to 24 weeks of gestation and was found to have a mean activity of 2.11 nmol per min per mg of protein. This was approximately 30 per cent of the postnatal controls assayed by the same method, but there was no evidence of a change in activity during the gestational period examined. If fetal liver tissue can be reliably obtained, it may be possible to determine a deficiency of glucose-6-phosphatase in fetuses who are at risk.     

Molecular systematic and phylogenetic assessment of 34 calanoid copepod species of the Calanidae and Clausocalanidae

DNA sequences for a 639 bp region of mitochondrial cytochrome oxidase I (mtCOI) were determined for 34 species of ten genera in two families of calanoid copepods, including: Calanoides, Cosmocalanus, Meoscalanus, Nannocalanus, Neocalanus, and Undinula (family Calanidae); and Clausocalanus, Ctenocalanus, Drepanopus, and Pseudocalanus (family Clausocalanidae). MtCOI gene sequences proved to be diagnostic molecular systematic characters for accurate identification and discrimination of the species. Levels of mtCOI variation within species (range: 1-4%) were significantly less than those between species (9-25%). Higher levels of intraspecific variation (>2%) usually resulted from comparisons between ecologically distinct or geographically isolated populations. MtCOI sequence variation resolved evolutionary relationships among species of Clausocalanus, Neocalanus, and Pseudocalanus, although there was evidence of saturation at some variable sites. Phylogenetic relationships among 11 copepod genera (adding Calanus to the list above) were reconstructed using a 660 bp region of nuclear small-subunit 18S rRNA, a slowly evolving gene that showed no variability within a species and differed by <1-6% among the genera. The 18S rRNA molecular phylogeny was consistent with the accepted limits of the Calanidae and Clausocalanidae and clearly resolved relationships among genera within each family. This molecular systematic and phylogenetic study was part of the ZooGene project, an international partnership to create a DNA sequence database as a tool for uniform, molecularly based species identification of planktonic calanoid copepods and euphausiids.     

Polyandry in the genus Apis, particularly Apis andreniformis

Using four polymorphic microsatellite loci, we found that four Apis andreniformis queens collected in Thailand each mated at least 10–20 times, producing an average relatedness, g _ww, of workers of 0.30 ± 0.007, and an average effective number of matings of 9.1 ± 2.2. The degrees of polyandry and intra-colonial genetic relatedness in A. andreniformis are similar to those in A. mellifera, slightly more than in A. florea, and up to 6 times less than in A. dorsata. We argue that while presently favoured hypotheses for the evolution of polyandry in monogynous social insects may adequately explain the evolution of up to five or six matings, they are inadequate to explain the extreme polyandry (10–60 matings) observed in Apis. One alternative possibility is that colony fitness is a non-additive function of the fitness of individual subfamilies. Such behavioral over-dominance may mean that queen fitness is increased by high levels of polyandry, which increase the probability of desirable combinations of worker genotypes occurring in one colony. The special attributes of honey bees which may lead to behavioral over-dominance include colony aggregation (which may increase the incidence of disease), and frequent long-distance migration. Received: 8 May 1996/Accepted after revision: 9 August 1996