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1.
Scientists engaged in the research of natural products often either conduct field collections themselves or collaborate with partners who do, such as botanists, mycologists, or SCUBA divers. The information gleaned from such collecting trips (e.g. longitude/latitude coordinates, geography, elevation, and a multitude of other field observations) have provided valuable data to the scientific community (e.g., biodiversity), even if it is tangential to the direct aims of the natural products research, which are often focused on drug discovery and/or chemical ecology. Geographic Information Systems (GIS) have been used to display, manage, and analyze geographic data, including collection sites for natural products. However, to the uninitiated, these tools are often beyond the financial and/or computational means of the natural product scientist. With new, free, and easy-to-use geospatial visualization tools, such as Google Earth, mapping and geographic imaging of sampling data are now within the reach of natural products scientists. The goals of the present study were to develop simple tools that are tailored for the natural products setting, thereby presenting a means to map such information, particularly via open source software like Google Earth.  相似文献   

2.
This is a paper about how men from Panapompom, an island in Milne Bay Province of Papua New Guinea (PNG), understand how they relate to white people and imagine the future. Until recently, men from Panapompom understood themselves to be engaged in a project of ‘development’, in which they would become more and more similar to white people. This was a desirable future. However, changes in the way Panapompom men work for money have resulted in a very different imagination of the future—one in which Panapompom people are not getting whiter, but blacker, and hence more and more excluded from the lives to which they aspire. Men now dive for bêche‐de‐mer, work which they regard as being particularly hard and dangerous. Diving has profound effects on the skin, blackening and hardening it, leading Panapompom men to liken themselves to the machines that create the wealth that white people use. These ‘mechanising’ effects that diving has on the black body lead men to see white people as the sole beneficiaries of the bêche‐de‐mer industry, and black people as mere tools or extensions. For bêche‐de‐mer divers, value and desired forms of life are lodged in Australia, Europe or America, while they find themselves excluded from this future by their growing blackness.  相似文献   

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Microarrays offer biologists comprehensive and powerful tools to analyze the involvement of genes in developmental processes at an unprecedented scale. Microarrays that employ defined sequences will permit us to elucidate genetic relationships and responses, while those that employ undefined DNA sequences (ESTs, cDNA, or genomic libraries) will help us to discover new genes, relate them to documented gene networks, and examine the way in which genes (and the process that they themselves control) are regulated. With access to broad new avenues of research come strategic and logistical headaches, most of which are embodied in the reams of data that are created over the course of an experiment. The solutions to these problems have provided interesting computational tools, which will allow us to compile huge data sets and to construct a genome-wide view of development. We are on the threshold of a new vista of possibilities where we might consider in comprehensive and yet specific detail, for example, the degree to which diverse organisms utilize similar genetic networks to achieve similar ends.  相似文献   

5.
Several sustainable building rating systems were created worldwide during the last decades due to economic growth and the significance of environmental impact associated with the building industry. Similar infrastructure rating tools have started to be developed and implemented, being highly necessary to promote its development. Even though the existing sustainable infrastructure rating systems are focused on advanced economies, growing environmental concerns are increasing the need for new systems in the Developing World. This research analyses some of the mainstream infrastructure rating frameworks such as Envision (USA), Civil Engineering Environmental Quality (CEEQUAL) assessment (UK) and Infrastructure Sustainability (IS) Rating Tool (Australia) from the perspective of the Triple Bottom Line (economy, environment and society), in order to determine the effectiveness of their application in the context of the least developed countries. The analysis revealed that the three tools are biased towards the environmental dimension and are mainly oriented to developed countries. Consequently, the foundations on which these systems are based need to be further developed and enhanced to be of real relevance in poorer nations by balancing the weight of sustainable pillars, incorporating effective management guidelines and development goals set by United Nations declarations, and considering impacts beyond the single project framework.  相似文献   

6.
Ecologists have long been concerned that contemporary fire regimes of central Australia have poor consequences for some plant species, vegetation communities and the native animals they support. Fire frequency, size and intensity (the ‘fire regime’) have all been implicated in the decline of native biota and in vegetation changes that potentially constitute ecological drift. However, not all perceived declines and changes are quantified or proven. The fire regimes themselves defy quantification and are arguably unknowable. We examine the relationships between fire, vegetation and the physical landscape and consider the adequacy of available knowledge for guiding fire management. Devising targeted ‘fire management regimes’, which take into account vegetation type and management objectives such as pastoral production, conservation and cultural observance, and which actively use fire to achieve those objectives, is a more realistic goal than controlling unquantifiable fire regimes in spatially diverse landscapes.  相似文献   

7.
The control of vertebrate pests by vertebrate predators   总被引:1,自引:0,他引:1  
Carnivores can control mammalian pests for long periods, but only after pest numbers have been reduced by other means. In Australia, the cause is prolonged dry weather. The consequent low populations of rabbits can then be regulated by European foxes, feral cats and dingoes. Kangaroos, and probably feral goats and pigs, succumb to dingoes at the same time, as substitute prey for rabbits. In the general case, such regulatory predation may be triggered climatically, by disease or by human intervention. When predators are themselves pests to be controlled, integrated pest management may be required to avoid unwanted resurgences of other pests.  相似文献   

8.
Science-based management confers a variety of benefits to wildlife populations that are cooperatively managed by zoos and aquariums, including those managed through the Association of Zoos and Aquariums. Briefly, when management strategies are successful, they result in reproductively robust populations that better retain genetic diversity and limit inbreeding than unmanaged populations. Although the benefits of demographic and genetic management have been well documented throughout both the scientific and popular literature, it has also been established that the majority of managed populations in zoos and aquariums are not meeting the minimum criteria believed to convey long-term biological viability. For most of these populations, an inability to meet viability criteria is not an inherent failure of how cooperative management is implemented. Furthermore, in recent years, we have perceived that the need to meet specific viability goals sometimes has obscured the benefits that these populations receive from rigorous, science-based management. To better clarify the conversation surrounding population viability in zoos and aquariums, we seek to decouple viability measures and how they predict population persistence from the benefits conferred to populations through science-based management. A primary goal of population management is to facilitate the persistence of priority species for longer than would be expected if no such management were implemented. Although current viability measures and future projections of viability are important tools for assessing the likelihood of population persistence, they are not indicators of which populations may most benefit from science-based management. Here, we review the history and purpose of applying science-based management to zoo and aquarium populations, describe measures of population viability and caution against confusing those measures of viability with population management goals or long-term population sustainability, and clearly articulate the benefits conferred to zoo and aquarium populations by science-based management.  相似文献   

9.
Marine telemetry expands the knowledge of the biology of marine species at risk: their life cycles, activities, interactions, habitats, and threats. Four seal species in Canada and Australia are faced with distinctive and divergent management problems. This article examines their conservation status, legal protection, and the role that telemetry has played, or could play, in providing previously unavailable information to help meet conservation goals. The value of telemetry data to minimize fisheries mortality of one species has been demonstrated in Australia. Despite there being significant telemetry data for the other species, policy and management have not yet responded.  相似文献   

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It is now accepted that most of the rivers and streams of Australia have been degraded to varying extents by European settlement. The scale and level of this degradation have been documented by State and Federal government authorities. To halt and reverse the degradation in the next two decades, it is crucial that the conservation and restoration of streams, rivers, riparian zones, and catchments become paramount in land and water management. Effective stream restoration requires a coordinated effort at the catchment level rather than at the level of many individual local sites. Monitoring, including the gathering of before-restoration data, and the setting of feasibly-attainable goals are key components of effective restoration. In planning projects and setting goals, it needs to be recognized that some goals may only be attained in the long-term. Large-scale restoration projects will require partnerships to be formed between resource managers and scientists, with other stakeholders possibly involved. Selected projects could be adaptively managed with the emphasis on gaining scientific knowledge on the effects of management interventions.  相似文献   

12.
In contrast to other approaches, evolutionary perspectives on understanding the power and wealth inequalities in human societies view wealth and power not as ends in themselves but as proximate goals that contribute to the ultimate Darwinian goal of achieving reproductive success. The most successful means of achieving it in specific times and places depend on local conditions and these have changed in the course of human history, to such an extent that strategies focused on the maintenance and increase of wealth can even be more successful in reproductive terms than strategies directed at maximizing reproductive success in the short term. This paper argues that a major factor leading to such changes is a shift in the nature of inter-generational wealth transfers from relatively intangible to material property resources and the opportunities these provided for massively increased inequality. This shift can be seen as a process of niche construction related to the increasing importance of fixed and defensible resources in many societies after the end of the last Ice Age. It is suggested that, despite problems of inference, the evidence of the archaeological record can be used to throw light on these processes in specific places and times.  相似文献   

13.
A large collection of genetic tools are available for those who wish to manipulate laboratory strains of cyanobacteria. These tools have not yet been applied to strains that might be used for more practical ends. Applications in which a natural ability of a cyanobacterial strain is exploited would require different genetic tools than those in which a cyanobacterial strain is called upon to produce a foreign product. DNA can be transferred into cyanobacteria by three methods: transformation, conjugation, and electroporation. With each, efficiency is greatly affected by restriction enzymes within the recipient cyanobacterium. Transferred DNA may be propagated in the recipient strain if carried on a replicating plasmid or if integrated into the host chromosome. Different means of integration offer different advantages. Methods are available to increase and control the expression of genes of interest. These genetic tools are discussed with reference to specific problems that might be faced in the exploitation of cyanobacteria.  相似文献   

14.
Under discussion are such population groups as management unit (stock) and evolutionarily significant unit, along with the problem of short-term ans long-term goals of conservation activities and wildlife management. The short-term goals may differ from the long-term goals. Management units (stocks) are demographically independent populations, though genetically they may be interconnected to a high degree. It is at this level of population organization that the short-term nature management goals are reached: the preservation of stable reproduction of management units, and the exclusion of excessive pressure on small groups. The evolutionarily significant units have independent conservation status determined by significant reproductive isolation and unique adaptations. It is at this level that long-term management goals are reached: the conservation of the native population structure, the evolutionarily significant differences, the maximum genetic diversity, and, thus, the evolutionary potential.  相似文献   

15.
Maritime security concerns in the South China Sea are increasing for several reasons: higher volumes of shipping traffic, protection of exclusive economic zone resources, piracy, terrorist threats, greater international scrutiny of ports and shipping, and the modernization of regional naval and coast guard forces. Coastal states and international user states have many overlapping interests in the South China Sea, for example, in promoting safe navigation through its busy sea-lanes. On other issues, in particular, antipiracy or anti-maritime terrorism measures, they have different views about the seriousness of the threats and the responses necessary to address them. This article examines the convergent and divergent maritime security interests of coastal states (China, Indonesia, Malaysia, and Singapore) and international user states (Australia, India, Japan, and the United States) in the South China Sea. It finds that multiple stakeholders pursuing diverse interests have yet to close the gap between goals and means of achieving maritime security.  相似文献   

16.
Summary Conservation management in agricultural landscapes involves identification and prioritization of assets, and interventions to reverse or arrest decline. Planning requires synthesis of hydrological, ecological and agronomic information and intuitions. We provide a case study involving the Lake Warden Wetland System, a Ramsar‐listed site on the south coast of Western Australia threatened by salinity and flooding. As the relative merits of management options (including engineering‐based solutions and catchment revegetation) may be sensitive to climate change, we captured our knowledge and understanding of the effectiveness of options under different climate change scenarios using Bayesian belief networks. We insulated against overconfidence by an info‐gap analysis that describes the trade‐off between aspiration and immunity to uncertainty. Only engineering‐based solutions offer reasonable prospects for achieving stated conservation goals in the Lake Warden Wetland System within a 25‐year time horizon. Marginal gains derived from co‐investment in revegetation varied among the assets. We advocate explicit treatment of uncertainty and risk‐based approaches to decision‐making to equip managers with a means of progressing conservation goals. The complementary insights offered by Bayesian belief networks and info‐gap analysis provide a sound basis for managers to assess the extent to which candidate management actions are robust to uncertainty.  相似文献   

17.
W. M. Milne 《BioControl》1997,42(1-2):173-183
The spotted alfalfa aphid (SAA),Therioaphis trifolii (Monell)f. maculata, was first recorded in Australia in 1977. It is a major pest of lucerne and other pasture medics but not of clover (Trifolium spp.). The parasitoidTrioxys complanatus Quilis was introduced into Australia in late 1977 as part of a biological control program for SAA and made a substantial contribution to the management of the pest. Since 1989, aphids which are individually indistinguishable from SAA have been causing substantial yield loss to clover pastures in western and south-eastern Australia. This aphid, now known in Australia as the spotted clover aphid (SCA), is genetically distinct from SAA and has a much wider host range. Populations of SCA in clover are rarely parasitised byT. complanatus. A series of experiments was undertaken to determine whether the greater susceptibility of SAA in lucerne than of SCA in clover to parasitisation byT. complanatus is due to the attraction of the parasitoid preferentially to lucerne or to the differential attractiveness of the aphids themselves. SAA and SCA were offered to the parasitoids in arenas of increasing complexity from single trifoliate leaves of lucerne and clover on agar through single potted plants in small cages to groups of potted plants in a large cage. Results showed that the parasitoids exhibited a preference for lucerne though, in the cage situation, they did find and parasitise SCA on clover. They did not differentiate between SAA and SCA on lucerne.  相似文献   

18.
Some Remarks on the Socio-Cultural Background of Restoration Ecology   总被引:2,自引:0,他引:2  
Restoration ecology plays an important role in nature conservation policy in Europe today. It establishes the scientific basis for restoring ecosystems altered or destroyed by man to a more “natural” state. The goals of restoration ecology can generally be described in terms of increased biodiversity, enhanced water retention capacity, avoidance of soil erosion, etc. In practice, however, a discrepancy exists between the high ideals of restoration goals and reality, where one often encounters limiting factors. These limiting factors can include the conflict between different restoration goals, the unpredictability of restoration goals owing to long‐term effects and stochastic events, the insufficient social acceptance of landscape changes during restoration processes, and the use of restoration processes themselves (e.g., undisturbed succession, certain management measures like impoverishment of fertilized areas) as restoration goals in place of a certain resource quality (such as species composition, population sizes, water quality). Two examples from southern Germany show that restoration goals in European cultural landscapes can only be implemented successfully when they are integrated into the respective land use systems.  相似文献   

19.
The study of the natural history of gelatinous zooplankton (‘gelata’) reached a high point at the end of the 19th century, when scientists first began to understand the phylogenetic and ecological links between cnidarians and ctenophores. Siphonophores, carefully figured in their entirety, and gauze-like lobate ctenophores too fragile to touch, were described by the dozens. In the ensuing years, focus on zooplankton shifted toward more ‘industrial’ goals such as quantitative sampling using plankton nets. While plankton scientists were busy summing tattered parts, they lost sight of the whole jellies themselves, and a crustaceocentric view of the ocean came to dominate. During this period, the most dramatic breakthroughs in cnidarian research came from laboratory studies of neurobiology, physiology, and development, particularly of certain model organisms. Now, at the turn of this century, we have the opportunity to bring gelata back into primacy. Submersibles and remotely operated vehicles allow us to study entire life histories of organisms that we did not even know existed. The tools of molecular biology allow us to answer questions about development, evolution, and phylogeny that had reached a stalemate. Even in the surface waters, where it might be thought that there is little left to learn, in situ observations have revealed unexpected interactions and hidden diversity. The critical roles that these organisms play in the health of the oceans, their position at the crux of many evolutionary debates, and the tools for biotechnology that they provide, have led to resurgent public appreciation and awareness. Although advanced tools do not necessitate good science, we have few excuses for failing to bring about another golden age of gelata. A plenary address of the 7th International Conference on Coelenterate Biology.  相似文献   

20.
Prey that are unprofitable to attack are typically conspicuous in appearance. Conventional theory assumes that these warning signals have evolved in response to predator receiver biases. However, such biases might be a symptom rather than a cause of warning signals. We therefore examine an alternative theory: that conspicuousness evolves in unprofitable prey to avoid confusion with profitable prey. One might wonder why unprofitable prey do not find a cryptic means to be distinct from profitable prey, reducing both their risk of confusion with profitable prey and their rate of detection by predators. Here we present the first coevolutionary model to allow for Batesian mimicry and signals with different levels of detectability. We find that unprofitable prey do indeed evolve ways of distinguishing themselves using cryptic signals, particularly when appearance traits can evolve in multiple dimensions. However, conspicuous warning signals readily evolve in unprofitable prey when there are more ways to look different from the background than to match it. Moreover, the more unprofitable the prey species, the higher its evolved conspicuousness. Our results provide strong support for the argument that unprofitable species evolve conspicuous signals to avoid confusion with profitable prey and indicate that peak shift in conspicuousness-linked traits is a major factor in its establishment.  相似文献   

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