Assessing ecosystem vulnerability to invasive rusty crayfish (Orconectes rusticus)

Despite the widespread introduction of nonnative species and the heterogeneity of ecosystems in their sensitivity to ecological impacts, few studies have assessed ecosystem vulnerability to the entire invasion process, from arrival to establishment and impacts. Our study addresses this challenge by presenting a probabilistic, spatially explicit approach to predicting ecosystem vulnerability to species invasions. Using the freshwater-rich landscapes of Wisconsin, USA, we model invasive rusty crayfish (Orconectes rusticus) as a function of exposure risk (i.e., likelihood of introduction and establishment of O. rusticus based on a species distribution model) and the sensitivity of the recipient community (i.e., likelihood of impacts on native O. virilis and O. propinquus based on a retrospective analysis of population changes). Artificial neural networks predicted that approximately 10% of 4200 surveyed lakes (n = 388) and approximately 25% of mapped streams (23 523 km total length) are suitable for O. rusticus introduction and establishment. A comparison of repeated surveys before vs. post-1985 revealed that O. virilis was six times as likely and O. propinquus was twice as likely to be extirpated in streams invaded by O. rusticus, compared to streams that were not invaded. Similarly, O. virilis was extirpated in over three-quarters of lakes invaded by O. rusticus compared to half of the uninvaded lakes, whereas no difference was observed for O. propinquus. We identified 115 lakes (approximately 3% of lakes) and approximately 5000 km of streams (approximately 6% of streams) with a 25% chance of introduction, establishment, and extirpation by O. rusticus of either native congener. By identifying highly vulnerable ecosystems, our study offers an effective strategy for prioritizing on-the-ground management action and informing decisions about the most efficient allocation of resources. Moreover, our results provide the flexibility for stakeholders to identify priority sites for prevention efforts given a maximum level of acceptable risk or based on budgetary or time restrictions. To this end, we incorporate the model predictions into a new online mapping tool with the intention of closing the communication gap between academic research and stakeholders that requires information on the prospects of future invasions.     

Trace metals and radionuclides in macroalgae from Moroccan coastal waters

Macroalgae species Codium sp, Bangia atropurpurea, Membranoptera alata, Plocamium cartilagineum, Dictyota dichotoma, Fucus spiralis and Stypocaulon scoparia were collected from seven stations along the north coast of Morocco. Samples were analysed to determine activities of naturally occurring radionuclides ((210)Pb, U isotopes and (40)K) and concentrations of metals (Zn, Fe, Co, Cu, Ni, Mn, Pb, Cd, As and Cr) using radiometric and ICP-OES techniques, respectively. Metal concentrations were within ranges reported in the scientific literature, and concentrations of bio-essential elements were in the order Mn>Fe> Zn>Cu in all samples. Brown algae had the highest concentrations of almost all metals, and concentrations decreased in the order brown>red>green algae. With respect to radionuclides, the red alga P. cartilagineum had the highest activities of (210)Pb, in most cases an order of magnitude higher than for the green alga Codium sp. (234)U and (238)U activities in all algae samples were in the range 0.96- 7.61 and 1.16-6.14 Bq/kg dry weight, respectively. Our analyses of radionuclide activities and metal concentrations in marine macroalgae showed large differences among taxa. These results provide insights into which algal species should be used for biomonitoring programmes.     

Reducing climate change gas emissions by cutting out stages in the life cycle of office paper

The paper industry's climate change gas emissions are growing. This article considers how to reduce emissions from cut-size office paper by bypassing stages in its life cycle. The options considered are: incineration, which cuts out landfill; localisation, which cuts out transport; annual fibre, which cuts out forestry and reduces pulping; fibre recycling, which cuts out landfill, forestry and pulping; un-printing, which cuts out all stages except printing; electronic-paper, which cuts out all stages. Un-printing may offer the greatest climate change emission reduction. There are uncertainties in this result, particularly in estimating the proportion of waste office paper would be suitable for un-printing.     

爱尔兰共和国境内的湖泊调查:水化学特性和酸敏感性

1997年在爱尔兰共和国进行了一项湖泊调查活动,本活动是确定并则绘临界负载的一个国家项目的一部分内容.共选取了200个湖泊作为调查的对象,约占湖泊总数的3.3‰.这个国家中的多数湖泊位于沿海岸带边缘的偏僻、高海拔、对酸具有敏感性的地区.在湖泊化学中来自海洋的物质的输入占据了主导地位.由于在大部分集水区中存在有机土壤,约有一半的湖泊中溶解有机碳(DOC)的含量大于5mg/L.在一半的湖泊中,非海洋硫酸盐的浓度处于背景水平上(＜20μeq/L).在7‰的抽查湖泊(13个湖泊)中发现临界负载超量.但由于海盐和有机酸之间的相互干扰,对临界负载的计算仍存在着不稳定性.在这种情况下如果进行精确的估计,就需要借助于长期的湖泊与沉积化学.     

Industrial relations stress and job satisfaction: Concurrent effects and mediation

We examine the effects of negative and positive industrial relations stress on both mood (negative and positive) and job satisfaction. Twenty industrial relations practitioners completed daily reports of industrial relations stress, mood, and job satisfaction over a 20-day period. After controlling for serial correlation, negative industrial relations stress affected negative mood and, in turn, job satisfaction. Positive industrial relations stress had direct effects on both positive mood and job satisfaction with positive mood also affecting job satisfaction. All effects were concurrent with no next-day effects of stress on mood or job satisfaction. Further research on industrial relations stress is both warranted and encouraged.     

Disentangling the relationship between the achievement striving and impatience—irritability dimensions of type A behavior,performance and health

This study was conducted to replicate and extend previous findings that two independent dimensions of type A behavior, namely Impatience—Irritability (II) and Achievement Striving (AS), differentially predict health and performance. One hundred and thirteen university students provided their grade point average and completed questionnaires to measure II, AS and several health measures. They also performed a five-minute proof-reading task which yielded a behavioral measure of attention and concentration. As predicted, after partialling out the effects of II, AS predicted GPA and proof-reading performance, but not health. After controlling for age and AS, II predicted headaches and sleep habits, but neither respiratory infections nor digestive problems. Implications for the differential prediction of health and performance by AS and II, and interventions designed to decrease risk from type A behavior by reducing II but not AS, are discussed.     

Evaluating complementary networks of restoration plantings for landscape‐scale occurrence of temporally dynamic species

Multibillion dollar investments in land restoration make it critical that conservation goals are achieved cost‐effectively. Approaches developed for systematic conservation planning offer opportunities to evaluate landscape‐scale, temporally dynamic biodiversity outcomes from restoration and improve on traditional approaches that focus on the most species‐rich plantings. We investigated whether it is possible to apply a complementarity‐based approach to evaluate the extent to which an existing network of restoration plantings meets representation targets. Using a case study of woodland birds of conservation concern in southeastern Australia, we compared complementarity‐based selections of plantings based on temporally dynamic species occurrences with selections based on static species occurrences and selections based on ranking plantings by species richness. The dynamic complementarity approach, which incorporated species occurrences over 5 years, resulted in higher species occurrences and proportion of targets met compared with the static complementarity approach, in which species occurrences were taken at a single point in time. For equivalent cost, the dynamic complementarity approach also always resulted in higher average minimum percent occurrence of species maintained through time and a higher proportion of the bird community meeting representation targets compared with the species‐richness approach. Plantings selected under the complementarity approaches represented the full range of planting attributes, whereas those selected under the species‐richness approach were larger in size. Our results suggest that future restoration policy should not attempt to achieve all conservation goals within individual plantings, but should instead capitalize on restoration opportunities as they arise to achieve collective value of multiple plantings across the landscape. Networks of restoration plantings with complementary attributes of age, size, vegetation structure, and landscape context lead to considerably better outcomes than conventional restoration objectives of site‐scale species richness and are crucial for allocating restoration investment wisely to reach desired conservation goals.