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881.
Summary. Female Photuris fireflies contain defensive chemicals of two types. They sequester steroidal pyrones (lucibufagins) from male fireflies of
the genus Photinus that they eat, and themselves produce the defensive betaine N-methylquinolinium 2-carboxylate. Chemical analyses of Photuris eggs showed that females that fed on Photinus males endow their eggs with both lucibufagin and the betaine, while those that did not feed on Photinus lay eggs that contain betaine, but virtually no lucibufagin. Photuris females collected in the field during the Photinus flight season laid eggs that invariably contained betaine, but lucibufagin only at times. Predation experiments showed that
Photuris eggs are essentially unacceptable to larvae of a coccinellid beetle (Harmonia axyridis) and an ant (Leptothorax longispinosus), but moderately acceptable to an earwig (Forficula auricularia). When applied experimentally to palatable insect eggs, lucibufagin proved deterrent to these three predators, while the
betaine proved deterrent to the ant and coccinellid larva only. Both types of defensive compound decreased egg predation in
the field. By endowing their eggs with both exogenous and endogenous chemicals, Photuris females are essentially “maximizing their options”– when feeding on Photinus, their eggs are doubly protected, but they are not entirely defenseless when the females are unable to procure lucibufagin.
Received 12 August 1999; accepted 27 August 1999 相似文献
882.
Jared D. Margulies Francesca R. Moorman Bárbara Goettsch Jan C. Axmacher Amy Hinsley 《Conservation biology》2023,37(3):e14030
Although illegal wildlife trade (IWT) represents a serious threat to biodiversity, research into the prevalence of illegal plant collection and trade remains scarce. Because cacti and succulents are heavily threatened by overcollection for often illegal, international ornamental trade, we surveyed 441 members of the cacti and succulent hobbyist collector community with a mixed quantitative and qualitative approach. We sought to understand collector perspectives on the Convention on the International Trade in Endangered Species of Wild Flora and Fauna (CITES) and on the threats IWT poses to cactus and succulent conservation. Most respondents (74% of 401 respondents) stated that illegal collection in cacti and succulents represents a “very serious problem” and that the problem of wild plant collection is increasing (72% of 319 respondents). Most forms of illegal collection and trade were seen as very unacceptable by respondents. Self-reported noncompliance with CITES rules was uncommon (11.2% of 418 respondents); it remains a persistent problem in parts of the cacti and succulent hobbyist community. People engaging in rule breaking, such as transporting plants without required CITES documents, generally did so knowingly. Although 60.6% of 381 respondents regarded CITES as a very important tool for conservation, sentiment toward CITES and its efficacy in helping species conservation was mixed. Collectors in our survey saw themselves as potentially playing important roles in cactus and succulent conservation, but this potential resource remains largely untapped. Our results suggest the need for enhanced consultation with stakeholders in CITES decision-making. For challenging subjects like IWT, developing evidence-based responses demands deep interdisciplinary engagement, including assessing the conservation impact of species listings on CITES appendices. 相似文献
883.
Mining activities are compatible with other activities in space and time if they are developed together and adapted to each other. If permits are required for two projects that are not considered to be compatible, the authorities will be forced to decide which one has prevalence. In the event of conflict or dispute, it is always preferable to attempt to seek compatibility between projects rather than waste time, effort and money on contesting the prevalence decision, as costly and lengthy lawsuits will only delay the development of both projects, with the resulting loss of business opportunities. In this article, technical solutions designed to achieve mining compatibility with other projects are described in terms of benefits and synergies for the projects and benefits for the government that avoid complex decisions and proceedings and optimize revenues. 相似文献
884.
Jøn Holm-Hansen 《Environmental Impact Assessment Review》1997,17(6):449-463
Authorities in Eastern European countries are looking for the best available policy tools from the West, and policy instruments tailored for a Western context are being introduced massively in the former state socialist countries of Europe. This study examines some of the contextual factors that hamper the introduction of modern, Western tools of environmental management within previously state socialist countries. These are highlighted through a comparison of how environmental impact assessment (EIA) is put into practice in Estonia and Norway. Estonia and Norway belong to the same European Baltic-Nordic region, but the two countries have a dramatically different history for most of this century. 相似文献
885.
Yngve Malmén Minna Nissilä Kimmo Virolainen Pasi Repola 《Journal of Loss Prevention in the Process Industries》2010,23(2):249-252
Chemical accidents during process plant shutdowns may have severe consequences. In spite of this, the safety management systems in place in many companies still mainly cover the normal operations and little explicitly addresses the maintenance shutdown and plant start-up phases. A Finnish research project found that the level of safety during shutdowns is more closely related to the skills of key individuals at the plants and less due to the systematic safety management system of the companies. A guidebook on the topic in conjunction with tools to improve the situation were developed during the project in order to help the companies improve their documentation associated with chemical safety during shutdowns. 相似文献
886.
Růžičková Jana Raclavská Helena Juchelková Dagmar Šafář Michal Kucbel Marek Švédová Barbora Slamová Karolina Grobelak Anna 《Environmental science and pollution research international》2023,30(4):8582-8600
Environmental Science and Pollution Research - The utilisation of waste wood from furniture production brings new problems connected with an incomplete thermochemical decomposition of additives... 相似文献
887.
Artisanal and small-scale gold mining (ASGM) is the principal anthropogenic activity that globally contributes to overloading our environment with mercury. Although the Minamata Convention, led by the United Nations, is a crucial instrument to eliminate its use progressively, novel approaches to accelerate this difficult transition are welcome. This article proposes a framework for policy-making or improvement, fostering the enforcement of mercury elimination through the lens of the 17 Sustainable Development Goals (SDGs), focusing on the excluded artisanal and small-scale gold miners and their dependents. We move forward with a literature review of the Artisanal and Small Mining topic, taking each SDG as a unit of analysis. Understanding the problem as a puzzle of four sets of pieces, namely: (1) social, (2) environmental, (3) economic, and (4) institutional, the paper offers potential opportunities for the decision-makers and practitioners to accelerate the substitution of this heavy metal and develop sustainable futures for the ASGM communities. We conclude by proposing a pragmatic framework that synthesizes the means, actions, and ends to accelerate a sustainable transition. 相似文献
888.
Towards a long-term integrated monitoring programme in Europe: network design in theory and practice
Parr TW Ferretti M Simpson IC Forsius M Kovács-Láng E 《Environmental monitoring and assessment》2002,78(3):253-290
Long-term integrated monitoring is an important approach forinvestigating, detecting and predicing the effects ofenvironmental changes. Currently, European freshwaters,glaciers, forests and other narural and semi-natural ecosystemsand habitats are monitored by a number of networks establishedby different organisations. However, many monitoring programmeshave a narrow focus (e.g. targeting individual ecosystems) andmost have different measurement protocols and sampling design.This has resulted in poor integration of ecosystem monitoring ata European level, leading to some overlapping of efforts and alack of harmonised data to inform policy decisions. The need fora consistent pan-European long-term integrated monitoring ofterrestrial systems programme is recognised in the scientificcommunity. However, the design of such a system can be problematic, not least because of the constraints imposed bythe need to make maximum use of existing sites and networks.Based on the outcomes of the NoLIMITS project (Networking ofLong-term Integrated Monitoring in Terrestrial Systems), thisarticle reviews issues that should be addressed in designing aprogramme based on existing monitoring sites and networks. Fourmajor design issues are considered: (i) users' requirements,(ii) the need to address multiple objectives, (iii) role ofexisting sites and (iv) operational aspects. 相似文献
889.
Fernández-Landero Sandra Giráldez Inmaculada Fernández-Caliani Juan Carlos 《Environmental geochemistry and health》2021,43(10):4251-4264
Environmental Geochemistry and Health - Chestnut soils developed over mineralized areas of southwestern Spain are characterized by high baseline concentrations of geogenic trace elements, notably... 相似文献
890.
Andráš Peter Dadová Jana Romančík Roman Borošová Daniela Midula Pavol Dirner Vojtech 《Environmental geochemistry and health》2021,43(9):3675-3681
Environmental Geochemistry and Health - The abandoned Malachov deposit belongs among the most important historic Hg deposits in the world. The soil, groundwater, surface water, plants, and animals... 相似文献