Linking local impacts to changes in climate: a guide to attribution

Assessing past impacts of observed climate change on natural, human and managed systems requires detailed knowledge about the effects of both climatic and other drivers of change, and their respective interaction. Resulting requirements with regard to system understanding and long-term observational data can be prohibitive for quantitative detection and attribution methods, especially in the case of human systems and in regions with poor monitoring records. To enable a structured examination of past impacts in such cases, we follow the logic of quantitative attribution assessments, however, allowing for qualitative methods and different types of evidence. We demonstrate how multiple lines of evidence can be integrated in support of attribution exercises for human and managed systems. Results show that careful analysis can allow for attribution statements without explicit end-to-end modeling of the whole climate-impact system. However, care must be taken not to overstate or generalize the results and to avoid bias when the analysis is motivated by and limited to observations considered consistent with climate change impacts.     

Biodiversity and food security: from trade-offs to synergies

Regional Environmental Change -     

我们怎样才能实质性地提高生态效率?

本文论述我们怎样才能实质性地提高工艺、产品和服务的生态效率这一问题.据认为,在环境改善方面显著向前跃进需要环境与其它政策领域的一体化,同时把长远可持续性牢记心中.这种思路称为"可持续性战略",是在荷兰的两个实例(来自蒂尔堡市和飞利浦公司声像/消费电子分公司)基础上制订的.为了评价该思路总体上的优点,建议进行更多的实验.     

Instruments and strategies to improve the eco-efficiency of products

This article examines what tools can be used to analyze and improve the environmental performance of a product. It discusses how companies can upgrade the environmental performance of products in a cost-effective way and enhance their competitive position in the market through product innovation. Based on current examples, it is concluded that a complete toolbox is available to assist companies in developing more eco-efficient products. Which combination of practices can best be applied depends on various factors, particularly the type of external demand(s) the company is facing, its available resources, its time horizon, and its environmental strategy. Experience shows that it is better for companies to be ahead of external criticism and act more proactively. This article shows how companies can follow four main strategies in which eco-efficient product development goes hand in hand with a better competitive position in the market: (1) an efficiency improvement strategy; (2) a market share improvement strategy; (3) a market development strategy; and (4) a product diversification strategy. Finally, the importance of product innovation is stressed in order to implement the eco-efficiency strategies mentioned above.     

Making sense of Corporate Social Responsibility: Exploring organizational processes and strategies

This article describes and analyzes how company members make sense of Corporate Social Responsibility (CSR). The research question focuses on organizational processes of structuring CSR in practice: How do CSR sensemaking processes in companies work and is it possible to discern process strategies?Based on universal sensemaking theories, a conceptual framework is developed to analyze CSR sensemaking in practice. When the framework is used to analyze the experiences of 18 companies we are able to characterize internal CSR sensemaking as a process that consists of a three-stage cycle with an important role for change agents. Further, we conclude that the companies develop unique interpretations of the three-stage cycle. Grouping the processes, we discern two strategies of communicating and acting that stimulate the involvement of people and embed CSR values in the company.     

Testing a post-copulatory pre-zygotic reproductive barrier in a passerine species pair

Sexual selection may drive speciation, but most research focuses on pre-copulatory sexual selection, overlooking post-copulatory processes. Post-copulatory sexual selection in allopatric populations could drive divergence in post-copulatory pre-zygotic (PCPZ) phenotypes, limiting gene flow upon secondary contact. Here, we performed in vitro experiments examining one potential PCPZ barrier between two closely related passerine species, house sparrows (Passer domesticus) and Spanish sparrows (Passer hispaniolensis). In birds, crossing in the vagina may be particularly challenging for sperm, so we tested the effect of female reproductive tract fluids on sperm swimming speed and motility. If a PCPZ barrier exists at this stage of the fertilization process, heterospecific female fluids are predicted to reduce sperm swimming speed or motility relative to conspecific female fluid. We found that house sparrow female fluids affected the two species’ sperm asymmetrically, depending on the control sperm velocity and male species. Overall, however, sperm performed equally in conspecific and heterospecific female fluids, and the species had similar sperm morphology and sperm swimming performance. Low divergence in PCPZ phenotypes between species, perhaps because post-copulatory sexual selection is stabilizing or only moderately strong in these taxa, may be insufficient to cause an overall PCPZ barrier. Reinforcement may be unlikely to drive PCPZ barriers for this species pair, because relatively effective pre-copulatory barriers exist between the species, and because hybrids can be quite successful. Testing the role of PCPZ barriers in birds with more divergent PCPZ phenotypes will improve our understanding of speciation in passerines.