Mitigating the impacts of rainforest roads in Queensland’s Wet Tropics: Effective or are further evaluations and new mitigation strategies required?

Summary Research into mitigation of the ecological impacts of rainforest roads in North Queensland has a long history, commencing during the formative years of Australian road ecology. In Queensland’s Wet Tropics and throughout Australia, installation of engineered structures to ameliorate ecological road impacts is now common during larger construction projects, but unusual in smaller road projects. Retro‐fitting of engineering solutions to roads that are causing obvious impacts is also uncommon. Currently, Australian mitigation measures concentrate on two important impacts: road mortality and terrestrial habitat fragmentation. Unfortunately, other important ecological impacts of roads are seldom addressed. These include edge effects, traffic disturbance, exotic invasions and fragmentation of stream habitats. In North Queensland, faunal underpasses and canopy bridges across rainforest roads have been monitored over long periods. These structures are used frequently by multiple individuals of various species, implying effectiveness for movements and dispersal of many generalist and specialised rainforest animals. However, without addressing population and genetic implications, assessment of effectiveness of these connectivity structures is not holistic. These aspects need sufficient long‐term funding to allow similar systematic monitoring before and after construction. Throughout Australia, more holistic approaches to mitigation of road impacts would routinely examine population and genetic connectivity, consider mitigation against more ecological impacts where appropriate and include landscape‐scale replication.     

Railway ecology: Underrepresented in science?

Over the past two decades, the effects of roads on wildlife have been extensively studied. Theoretically, railways cause similar effects as well, yet ecologists do not understand the magnitude of these effects. Despite the field of road ecology rapidly expanding and the large footprint created by railways, there is a prominent lack of research related to railways and their effects on wildlife. To emphasize gaps between road and railway wildlife studies, we performed a thorough systematic review of twelve peer-reviewed journals in which ecologists and conservation biologists commonly publish. We found a clear underrepresentation of railway studies despite the potential negative ecological effects associated with this important anthropogenic feature. We found 259 road-wildlife articles and only 17 railway-wildlife articles in the journals we assessed with the majority of road studies focused in North America and the majority of railway studies in Europe. Although road-wildlife studies have increased through time, railway-wildlife studies have remained stagnant. In our opinion, the development of research pertaining to ‘Railway Ecology’ is long overdue.     

Road exposure and the detectability of birds in field surveys

Road ecology, the study of the impacts of roads and their traffic on wildlife, including birds, is a rapidly growing field, with research showing effects on local avian population densities up to several kilometres from a road. However, in most studies, the effects of roads on the detectability of birds by surveyors are not accounted for. This could be a significant source of error in estimates of the impacts of roads on birds and could also affect other studies of bird populations. Using road density, traffic volume and bird count data from across Great Britain, we assess the relationships between roads and detectability of a range of bird species. Of 51 species analysed, the detectability of 36 was significantly associated with road exposure, in most cases inversely. Across the range of road exposure recorded for each species, the mean positive change in detectability was 52% and the mean negative change was 36%, with the strongest negative associations found in smaller-bodied species and those for which aural cues are more important in detection. These associations between road exposure and detectability could be caused by a reduction in surveyors’ abilities to hear birds or by changes in birds’ behaviour, making them harder or easier to detect. We suggest that future studies of the impacts of roads on populations of birds or other taxa, and other studies using survey data from road-exposed areas, should account for the potential impacts of roads on detectability.     

Molecular ecology of fungal entomopathogens: molecular genetic tools and their applications in population and fate studies

The power of molecular genetic techniques to address ecological research questions has opened a distinct interdisciplinary research area collectively referred to as molecular ecology. Molecular ecology combines aspects of diverse research fields like population and evolutionary genetics, as well as biodiversity, conservation biology, behavioural ecology, or species-habitat interactions. Molecular techniques detect specific DNA sequence characteristics that are used as genetic markers to discriminate individuals or taxonomic groups, for instance in analyses of population and community structures, for elucidation of phylogenetic relationships, or for the characterization and monitoring of specific strains in the environment. Here, we summarize the PCR-based molecular techniques used in molecular ecological research on fungal entomopathogens and discuss novel techniques that may have relevance to the studies of entomopathogenic fungi in the future. We discuss the flow chart of the molecular ecology approaches and we highlight some of the critical steps involved. There are still many unresolved questions in the understanding of the ecology of fungal entomopathogens. These include population characteristics and relations of genotypes and habitats as well as host-pathogen interactions. Molecular tools can provide substantial support for ecological research and offer insight into this far inaccessible systems. Application of molecular ecology approaches will stimulate and accelerate new research in the field of entomophathogen ecology.     

道路生态学中的景观生态问题

道路具有重要的景观生态影响,是道路生态学研究的热点问题之一。本文综述了道路生态学的研究历程和概况,从基础理论研究、道路对生物和理化环境的影响、道路与景观格局以及道路与土地利用/覆盖变化4个方面论述了目前道路生态学中景观生态问题的主要研究内容,并根据现有的研究成果概括了该领域的主要研究方法,即生物调查、道路缓冲区/影响区分析、叠图分析和综合分析。提出中国道路生态学中景观生态问题研究存在的主要问题,并对该领域未来的研究热点进行了展望。     

Ecological genetics of invasive alien species

There is growing realisation that integrating genetics and ecology is critical in the context of biological invasions, since the two are explicitly linked. So far, the focus of ecological genetics of invasive alien species (IAS) has been on determining the sources and routes of invasions, and the genetic make-up of founding populations, which is critical for defining and testing ecological and evolutionary hypotheses. However an ecological genetics approach can be extended to investigate questions about invasion success and impacts on native, recipient species. Here, we discuss recent progress in the field, provide overviews of recent methodological advances, and highlight areas that we believe are of particular interest for future research. First, we discuss the main insights from studies that have inferred source populations and invasion routes using molecular genetic data, with particular focus on the role of genetic diversity, adaptation and admixture in invasion success. Second, we consider how genetic tools can lead to a better understanding of patterns of dispersal, which is critical to predicting the spread of invasive species, and how studying invasions can shed light on the evolution of dispersal. Finally, we explore the potential for combining molecular genetic data and ecological network modelling to investigate community interactions such as those between predator and prey, and host and parasite. We conclude that invasions are excellent model systems for understanding the role of natural selection in shaping phenotypes and that an ecological genetics approach offers great potential for addressing fundamental questions in invasion biology.     

分子标记技术在昆虫入侵研究中的应用

遗传变异与种群持续性及其进化潜力密切相关,而生物入侵导致种群遗传变异或遗传多样性的改变为研究自然界中各种生态和进化问题提供了理想模式。分子标记技术是调查种群遗传变异的重要工具,揭示了入侵种的入侵过程和结果,并预测未来的发生情况。本综述归纳了分子标记技术在昆虫入侵机制研究中的应用,以典型的研究个案为例,分别综述了分子标记技术在隐蔽入侵的监测应用,分子标记技术在重构入侵历史研究中的推算方式,分子标记技术在探索种群遗传变异与成功入侵机制方面取得的重要进展,并进一步介绍了高分辨率熔解曲线（high-resolution melting, HRM）分析在昆虫入侵研究中的应用前景。     

The genetic effects of roads: A review of empirical evidence

Roads exert various effects of conservation concern. They cause road mortality of wildlife, change the behaviour of animals and lead to habitat fragmentation. Roads also have genetic effects, as they restrict animal movement and increase the functional isolation of populations. We first formulate theoretical expectations on the genetic effects of roads with respect to a decrease in genetic diversity and an increase in genetic differentiation or distance of populations or individuals. We then review the empirical evidence on the genetic effects of roads based on the available literature. We found that roads often, but not always, decrease the genetic diversity of affected populations due to reduced population size and genetic drift. Whether the reduction in genetic diversity influences the long-term fitness of affected populations is, however, not yet clear. Roads, especially fenced highways, also act as barriers to movement, migration and gene flow. Roads therefore often decrease functional connectivity and increase the genetic differentiation of populations or the genetic distance among individuals. Nevertheless, roads and highways rarely act as complete barriers as shown by genetic studies assessing contemporary migration across roads (by using assignment tests). Some studies also showed that road verges act as dispersal corridors for native and exotic plants and animals. Genetic methods are well suited to retrospectively trace such migration pathways. Most roads and highways have only recently been built. Although only few generations might thus have passed since road construction, our literature survey showed that many studies found negative effects of roads on genetic diversity and genetic differentiation in animal species, especially for larger mammals and amphibians. Roads may thus rapidly cause genetic effects. This result stresses the importance of defragmentation measures such as over- and underpasses or wildlife bridges across roads.     

“973”项目“农林危险生物入侵机理与控制基础研究”简介

2002年12月,国家重点基础研究发展计划("973"项目)"农林危险生物入侵机理与控制基础研究"经科技部批准正式立项,2003年启动。文章主要介绍该项目的立项背景、主要研究内容、研究方案和技术路线、总体研究目标及研究进展。     

Measures to reduce population fragmentation by roads: what has worked and how do we know?

Roads impede animal movement, which decreases habitat accessibility and reduces gene flow. Ecopassages have been built to mitigate this but there is little research with which to evaluate their effectiveness, owing to the difficulty in accessing results of existing research; the lack of scientific rigor in these studies; and the low priority of connectivity planning in road projects. In this article, we suggest that the imperative for improving studies of ecopassage effectiveness is that road ecology research should be included from the earliest stages of road projects onwards. This would enable before-after-control-impact (BACI) design research, producing useful information for the particular road project as well as rigorous results for use in future road mitigation. Well-designed studies on ecopassage effectiveness could help improve landscape connectivity even with the increasing number and use by traffic of roads.     

Application of proteomics to ecology and population biology

Proteomics is a relatively new scientific discipline that merges protein biochemistry, genome biology and bioinformatics to determine the spatial and temporal expression of proteins in cells, tissues and whole organisms. There has been very little application of proteomics to the fields of behavioral genetics, evolution, ecology and population dynamics, and has only recently been effectively applied to the closely allied fields of molecular evolution and genetics. However, there exists considerable potential for proteomics to impact in areas related to functional ecology; this review will introduce the general concepts and methodologies that define the field of proteomics and compare and contrast the advantages and disadvantages with other methods. Examples of how proteomics can aid, complement and indeed extend the study of functional ecology will be discussed including the main tool of ecological studies, population genetics with an emphasis on metapopulation structure analysis. Because proteomic analyses provide a direct measure of gene expression, it obviates some of the limitations associated with other genomic approaches, such as microarray and EST analyses. Likewise, in conjunction with associated bioinformatics and molecular evolutionary tools, proteomics can provide the foundation of a systems-level integration approach that can enhance ecological studies. It can be envisioned that proteomics will provide important new information on issues specific to metapopulation biology and adaptive processes in nature. A specific example of the application of proteomics to sperm ageing is provided to illustrate the potential utility of the approach.     

旅游地道路生态持续性评价——以云南省玉龙县为例

从生态效应与连通功能两个角度,综合运用景观格局指数、总体变异系数、稳定性系数等方法,以云南省玉龙县为例,构建旅游地道路生态持续性评价体系,定量评价全县主要旅游道路生态持续性状态及其空间分异。结果表明,研究区道路的生态持续性状态总体良好,有助于旅游业发展,同时对生态系统影响有限;受承载游客规模不同、沿线生态系统敏感性差异等因素影响,玉龙县道路的生态持续性具有明显的空间差异;旅游地道路生态持续性的影响因素主要包括道路所承载的旅游活动强度,道路的坡度,道路周边山体的地质构造,道路所经过区域的生态系统敏感程度等。     

Large Roads Reduce Bat Activity across Multiple Species

Although the negative impacts of roads on many terrestrial vertebrate and bird populations are well documented, there have been few studies of the road ecology of bats. To examine the effects of large roads on bat populations, we used acoustic recorders to survey bat activity along ten 300 m transects bordering three large highways in northern California, applying a newly developed statistical classifier to identify recorded calls to the species level. Nightly counts of bat passes were analyzed with generalized linear mixed models to determine the relationship between bat activity and distance from a road. Total bat activity recorded at points adjacent to roads was found to be approximately one-half the level observed at 300 m. Statistically significant road effects were also found for the Brazilian free-tailed bat (Tadarida brasiliensis), big brown bat (Eptesicus fuscus), hoary bat (Lasiurus cinereus), and silver-haired bat (Lasionycteris noctivagans). The road effect was found to be temperature dependent, with hot days both increasing total activity at night and reducing the difference between activity levels near and far from roads. These results suggest that the environmental impacts of road construction may include degradation of bat habitat and that mitigation activities for this habitat loss may be necessary to protect bat populations.     

道路生态研究进展

道路广泛分布在各种景观中,其密度和交通量都不断增加,随之带来多方面的生态影响:道路建设导致动植物死亡和生境丧失、物理化学环境变化、路旁植被改变.对动物种群产生的生态影响包括道路致死、道路回避和巢区转移、移动格局改变、障碍作用导致生境和种群的破碎化.道路还强烈地改变景观格局和过程.道路生态影响的定量化测度指数包括道路密度、道路位置和道路影响域,道路生态研究在道路规划和野生动物保护中有很广阔的应用前景,成为生态学的一个重要领域.     

道路生态研究进展

道路广泛分布在各种景观中,其密度和交通量都不断增加,随之带来多方面的生态影响：道路建设导致动植物死亡和生境丧失、物理化学环境变化、路旁植被改变。对动物种群产生的生态影响包括道路致死、道路回避和巢区转移、移动格局改变、障碍作用导致生境和种群的破碎化。道路还强烈地改变景观格局和过程。道路生态影响的定量化测度指数包括道路密度、道路位置和道路影响域,道路生态研究在道路规划和野生动物保护中有很广阔的应用前景,成为生态学的一个重要领域。     

Advancing ecological understandings through technological transformations in noninvasive genetics

Noninvasive genetic approaches continue to improve studies in molecular ecology, conservation genetics and related disciplines such as forensics and epidemiology. Noninvasive sampling allows genetic studies without disturbing or even seeing the target individuals. Although noninvasive genetic sampling has been used for wildlife studies since the 1990s, technological advances continue to make noninvasive approaches among the most used and rapidly advancing areas in genetics. Here, we review recent advances in noninvasive genetics and how they allow us to address important research and management questions thanks to improved techniques for DNA extraction, preservation, amplification and data analysis. We show that many advances come from the fields of forensics, human health and domestic animal health science, and suggest that molecular ecologists explore literature from these fields. Finally, we discuss how the combination of advances in each step of a noninvasive genetics study, along with fruitful areas for future research, will continually increase the power and role of noninvasive genetics in molecular ecology and conservation genetics.     

Phytochemical diversity and synergistic effects on herbivores

Synergistic effects of multiple plant secondary metabolites on upper trophic levels constitute an underexplored but potentially widespread component of coevolution and ecological interactions. Examples of plant secondary metabolites acting synergistically as insect deterrents are not common, and many studies focus on the pharmaceutical applications of natural products, where activity is serendipitous and not an evolved response. This review summarizes some systems that are ideal for testing synergistic plant defenses and utilizes a focused meta-analysis to examine studies that have tested effects of multiple compounds on insects. Due to a dearth of ecological synergy studies, one of the few patterns for synergy that we are able to report from the meta-analysis is that phytochemical mixtures have a larger overall effect on generalist herbivores than specialist herbivores. We recommend a focus on synergy in chemical ecology programs and suggest future hypothesis tests and methods. These approaches are not focused on techniques in molecular biology to examine mechanisms at the cellular level, rather we recommend uncovering the existence of synergy first, by combining the best methods in organic synthesis, isolation, chemical ecology, bioassays, and quantitative analyses. Data generated by our recommended methods should provide rigorous tests of important hypotheses on how intraclass and interclass compounds act synergistically to deter insects, disrupt the immune response, and ultimately contribute to diversification. Further synergy research should also contribute to determining if antiherbivore synergy is widespread among plant secondary metabolites, which would be consistent with the hypothesis that synergistic defenses are a key attribute of the evolved diverse chemical mixtures found in plants.     

Quantitatively Evaluating Restoration Experiments: Research Design, Statistical Analysis, and Data Management Considerations

Conceptual and logistical challenges associated with the design and analysis of ecological restoration experiments are often viewed as being insurmountable, thereby limiting the potential value of restoration experiments as tests of ecological theory. Such research constraints are, however, not unique within the environmental sciences. Numerous natural and anthropogenic disturbances represent unplanned, uncontrollable events that cannot be replicated or studied using traditional experimental approaches and statistical analyses. A broad mix of appropriate research approaches (e.g., long-term studies, large-scale comparative studies, space-for-time substitution, modeling, and focused experimentation) and analytical tools (e.g., observational, spatial, and temporal statistics) are available and required to advance restoration ecology as a scientific discipline. In this article, research design and analytical options are described and assessed in relation to their applicability to restoration ecology. Significant research benefits may be derived from explicitly defining conceptual models and presuppositions, developing multiple working hypotheses, and developing and archiving high-quality data and metadata. Flexibility in research approaches and statistical analyses, high-quality databases, and new sampling approaches that support research at broader spatial and temporal scales are critical for enhancing ecological understanding and supporting further development of restoration ecology as a scientific discipline.     

Accidental experiments: ecological and evolutionary insights and opportunities derived from global change

Humans are the dominant ecological and evolutionary force on the planet today, transforming habitats, polluting environments, changing climates, introducing new species, and causing other species to decline in number or go extinct. These worrying anthropogenic impacts, collectively termed global change, are often viewed as a confounding factor to minimize in basic studies and a problem to resolve or quantify in applied studies. However, these ‘accidental experiments’ also represent opportunities to gain fundamental insight into ecological and evolutionary processes, especially when they result in perturbations that are large or long in duration and difficult or unethical to impose experimentally. We demonstrate this by describing important fundamental insights already gained from studies which utilize global change factors as accidental experiments. In doing so, we highlight why accidental experiments are sometimes more likely to yield insights than traditional approaches. Next, we argue that emerging environmental problems can provide even more opportunities for scientific discovery in the future, and provide both examples and guidelines for moving forward. We recommend 1) a greater flow of information between basic and applied subfields of ecology and evolution to identify emerging opportunities; 2) considering the advantages of the ‘accidental experiment’ approach relative to more traditional approaches; and 3) planning for the challenges inherent to uncontrolled accidental experiments. We emphasize that we do not view the accidental experiments provided by global change as replacements for scientific studies quantifying the magnitude of anthropogenic impacts or outlining strategies for mitigating impacts. Instead, we believe that accidental experiments are uniquely situated to provide insights into evolutionary and ecological processes that ultimately allow us to better predict and manage change on our human‐dominated planet. Synthesis Humans have an increasingly large impact on the planet. In response, ecologists and evolutionary biologists are dedicating increasing scientific attention to global change, largely with studies documenting biological effects and testing strategies to avoid or reverse negative impacts. In this article, we analyze global change from a different perspective, and suggest that human impacts on the environment also serve as valuable ‘accidental experiments’ that can provide fundamental scientific insight. We highlight and synthesize examples of studies taking this approach, and give guidance for gaining future insights from these unfortunate ‘accidental experiments’.     

The impact of global climate change on genetic diversity within populations and species

Genetic diversity provides the basic substrate for evolution, yet few studies assess the impacts of global climate change (GCC) on intraspecific genetic variation. In this review, we highlight the importance of incorporating neutral and non‐neutral genetic diversity when assessing the impacts of GCC, for example, in studies that aim to predict the future distribution and fate of a species or ecological community. Specifically, we address the following questions: Why study the effects of GCC on intraspecific genetic diversity? How does GCC affect genetic diversity? How is the effect of GCC on genetic diversity currently studied? Where is potential for future research? For each of these questions, we provide a general background and highlight case studies across the animal, plant and microbial kingdoms. We further discuss how cryptic diversity can affect GCC assessments, how genetic diversity can be integrated into studies that aim to predict species' responses on GCC and how conservation efforts related to GCC can incorporate and profit from inclusion of genetic diversity assessments. We argue that studying the fate of intraspecifc genetic diversity is an indispensable and logical venture if we are to fully understand the consequences of GCC on biodiversity on all levels.