Home range shifts by breeding female Townsend's voles (Microtus townsendii ): a test of the territory bequeathal hypothesis

Numerous accounts of partial or complete breeding dispersal by adult females reported in the literature on microtines have been interpreted as maternal bequeathal. However, for most species, no causal relationship between a female's movements between successive litters and the settlement of her offspring in the natal range has been demonstrated. I tested predictions from the bequeathal hypothesis using data from an intensive study of Townsend's voles where genetical relationship had been determined by marking most pups in the maternal nest before weaning. After correcting statistically for temporal changes in the distance moved between successive litters I rejected the following predictions: (1) that females with one or several daughters of reproductive age should be more likely to disperse or disperse farther between successive births than females without such daughters; (2) that mothers should be more likely to bequeath their range to their daughters in spring when the latter would gain most from having ready access to a breeding range; (3) that daughters benefit from their mother abandoning the natal range through an increase in their probability of recruitment; and (4) that daughters actually use the home range vacated by their mother. I critically reassess the empirical studies quoted as evidence that breeding dispersal is a form of parental investment in microtines and other mammals. Most empirical studies cited in support of the bequeathal hypothesis often only contain anecdotal reports of movements by breeding females or do not mention it as one of its possible adaptive functions. Some studies contain evidence only consistent with the bequeathal hypothesis whereas others are incompatible with this explanation. Documented evidence of bequeathal comes exclusively from species which rely on a semi-permanent resource such as a midden, mound or burrow. I conclude that there is no indication from Townsend's voles or any other microtines that females abandon their breeding range to their female offspring as a form of parental investment. Received: 27 February 1996 / Accepted after revision: 1 March 1997     

Effects of pesticides on soil enzymes: a review

The use of pesticides in agriculture has highly increased during the last 40 years to increase crop yields. However, today most pesticides are polluting water, soil, atmosphere and food. Pesticides are also impact soil enzymes, which are essential catalysts ruling the quality of soil life. In particular, the activity of soil enzymes control nutrient cycles, and, in turn, fertilization. Here, we review the effects of pesticides on the activity of soil enzymes in terrestrial ecosystems. Enzymes include dehydrogenase, fluorescein diacetate hydrolase, acid phosphatase, alkaline phosphatase, phosphatase, β-glucosidase, cellulase, urease and aryl-sulfatase. Those enzymes are involved in the cycles of carbon, nitrogen, sulfur and phosphorus. The main points of our analysis are (1) the common inhibition of dehydrogenase in 61 % of studies, stimulation of cellulase in 56 % of studies and no response of aryl-sulfatase in 67 % of studies. (2) Fungicides have mainly negative effects on enzymatic activities. (3) Insecticides can be classified into two groups, the first group represented by endosulfan having an overall positive impact while the second group having a negative effect. (4) Herbicides can be classified into two groups, one group with few positive effect and another group with negative effect.     

Discussion of “Tang,H., Zhang,H., & Yuan,S. (2018). Hydrodynamics and contaminant transport on a degraded bed at a 90-degree channel confluence. Environmental Fluid Mechanics, 18(2), 443–463”

The authors measured and computed the hydrodynamics and passive scalar dispersion in 90-degree open channel confluences over flat and degraded beds with a dominant upstream or tributary inflow. The present discussion essentially deals with the direction of rotation of the secondary currents, reported for the flat bed configuration with dominant tributary inflow. This rotation direction is indeed surprisingly opposite to the ones reported in the literature, both from calculations and measurements, even if present geometry slightly differs from literature geometries.     

欧洲零售业如何有助于促进可持续生产与消费

零售商的重要作用是对消费需求作出回应和提供各种产品.零售商是制造商和消费者之间的纽带,他们把消费需求上传给供应商,把产品和服务下传给他们的消费者.他们可以在很大程度上影响生产过程和消费方式的改变,他们所处的位置有利于向生产商施加压力,让他们支持更可持续的消费选择.许多零售商认识到了可持续发展战略的重要性,已经采取措施来满足对"绿色"产品的潜在需求.支持可持续发展战略的手段之一是法人的社会责任(CSR).虽然CSR概念的定义尚不明确,但是它关系到促进企业在基本立法要求以外的行动.欧洲贸易(EuroCommerce)成立了CSR问题工作小组.该工作组帮助确保主动代言零售部门,尤其是在欧洲委员会(EC)于2002年新创建的欧洲多利益相关者论坛中.EuroCommerce也是有效消费回应(ECR)运动的发起者之一.     

Life cycle assessment of biogas upgrading technologies

This article evaluates the life cycle assessment (LCA) of three biogas upgrading technologies. An in-depth study and evaluation was conducted on high pressure water scrubbing (HPWS), as well as alkaline with regeneration (AwR) and bottom ash upgrading (BABIU), which additionally offer carbon storage. AwR and BABIU are two novel technologies that utilize waste from municipal solid waste incinerators - namely bottom ash (BA) and air pollution control residues (APC) - and are able to store CO(2) from biogas through accelerated carbonation processes. These are compared to high pressure water scrubbing (HPWS) which is a widely used technology in Europe. The AwR uses an alkaline solution to remove the CO(2) and then the solution - rich in carbonate and bicarbonate ions - is regenerated through carbonation of APC. The BABIU process directly exposes the gas to the BA to remove and immediately store the CO(2), again by carbonation. It was determined that the AwR process had an 84% higher impact in all LCA categories largely due to the energy intensive production of the alkaline reactants. The BABIU process had the lowest impact in most categories even when compared to five other CO(2) capture technologies on the market. AwR and BABIU have a particularly low impact in the global warming potential category as a result of the immediate storage of the CO(2). For AwR, it was determined that using NaOH instead of KOH improves its environmental performance by 34%. For the BABIU process the use of renewable energies would improve its impact since accounts for 55% of the impact.     

How does agricultural intensification modulate changes in plant community composition?

Agricultural intensification, at local and landscape scales, has caused a decrease in plant diversity and changes in species composition in cereal fields. To better understand the role of landscape complexity and farming systems in shaping plant assemblages, it is of interest to focus on functional traits rather than on floristic composition, which may help to highlight trends in vegetation patterns. We analysed the relative abundance of various functional attributes (different life forms, growth forms, wind-pollinated species and wind-dispersed species) at three contrasted field positions (boundary, edge and centre) of 29 organic and 29 conventional cereal fields distributed in 15 agrarian localities of NE Spain. Agricultural intensification affected the biological attributes of the vegetation in dryland Mediterranean cereal fields; local factors (farming system and position) had a more prominent role in affecting plant functional composition than the surrounding landscape. Local factors were important for life form distribution, growth form and pollination type, whereas landscape complexity mainly affected the proportion of wind-dispersed species. Therefore, depending on the objective of the study, it is important to select functional attributes sensitive to the different scales of agricultural intensification, especially because landscape complexity and land-use intensity are commonly related.     

Worker size-related task partitioning in the foraging strategy of a seed-harvesting ant species

Messor bouvieri is a seed-harvesting ant species in which workers forage in trails from the nest to a search area. A previous observation of seed transfer events between workers returning to the nest suggested potential task partitioning. In this study, we describe seed transportation and analyze the role of task partitioning in the foraging strategy of this species in terms of seed intake efficiency in relation to costs and benefits based on transport speed and task reliability. We assess the harvesting efficiency of task partitioning by comparing cooperative seed transport (CST) and individual seed transport (IST) events. Our results show task partitioning in the form of a sequence of transfer events among workers going from the search area to the nest. Importantly, and despite the weak worker polymorphism of this species, this sequence involved workers of different sizes, with seeds usually being passed along from smaller to larger workers. In addition, we show that small workers are better at finding seeds (spend less time finding a seed), and large workers are better at transporting them (were faster when walking back to the nest and lost fewer seeds). However, we failed to demonstrate that workers of different sizes are specialized in performing the task in which they excel. Overall, sequential CST in M. bouvieri results in a greater seed intake because seed search time decreases and task reliability increases, compared to IST. The determinants and adaptive benefits of CST are discussed.     

PM source apportionment and trace metallic aerosol affinities during atmospheric pollution episodes: a case study from Puertollano, Spain

Source apportionment study was performed, applying principal component analysis to the results of 221 chemical analyses of PM10 and PM2.5 samples collected daily from the industrial (but low traffic) Spanish town of Puertollano over a 14-month period during 2004-2005. Results reveal compositional variations attributable to different mixtures of natural and anthropogenic materials, mainly soil and rock dust (crustal), marine salt (only in PM10), petrochemical refinery emissions, and particles attributed to the combustion of local coal, which is unusually rich in Pb and Sb. During the study period there were 34 pollution episodes when PM10 exceeded 50 tg m(-3), mostly due to winter air temperature inversions, regional atmospheric stagnation, or African dust incursions (North African, NAF days: usually in summer). Whereas the crustal component during NAF episodes averaged 52% with a PM2.5/PM10 ratio of 0.54, this dropped to 29% and a PM2.5/PM10 of 0.67 during non-NAF days when anthropogenic materials predominated. Abnormally enhanced concentrations of pathfinder metallic trace elements provide additional evidence for source apportionment: thus aerosols with raised levels of Pb and Sb are associated with local coal combustion, Ni and V can be linked to petrochemical PM emissions, and Ti, Mn, Rb, and Ce are particularly characteristic of crustal dust incursions.     

Dissipation kinetics and assessment of processing factor for chlorpyrifos and lambda-cyhalothrin in cardamom

The dissipation kinetics and method for estimation of residues of chlorpyrifos and lambda-cyhalothrin in cardamom were studied and developed. The limit of detection and limit of quantitation arrived for the compounds were 0.01 and 0.025 μg?g^?1, respectively. Gas chromatographic response of chlorpyrifos and lambda-cyhalothrin residues was linear in the range of 0.01–0.50 μg?g^?1 and the mean recovery obtained was 97.3 % for chlorpyrifos and 98.9 % for lambda-cyhalothrin with satisfactory relative standard deviation values. The mean initial residues of chlorpyrifos applied at a concentration of 0.05 % in cardamom was 2.5 μg?g^?1 and the residue was 8.1 μg?g^?1 after processing, with a processing factor of 3.24, while lambda-cyhalothrin when applied at 0.0025 % resulted in initial residues of 1.63 μg?g^?1 that magnified to 4.86 μg?g^?1 on curing, with a processing factor of 2.98. The half-life of chlorpyrifos was in the range of 5.1–5.24 days while that of lambda-cyhalothrin was in the range of 4.40–4.55 days. The processing factor arrived at in the above experiment lead to the conclusion that the residues of chlorpyrifos got magnified to 3.24–3.68 times and that of lambda-cyhalothrin got magnified to 2.98–3.46 times of initial residues, consequent to loss of weight due to dehydration during curing.