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1.
In the Anthropocene, coupled human and natural systems dominate and only a few natural systems remain relatively unaffected by human influence. On the one hand, conservation criteria based on areas of minimal human impact are not relevant to much of the biosphere. On the other hand, conservation criteria based on economic factors are problematic with respect to their ability to arrive at operational indicators of well‐being that can be applied in practice over multiple generations. Coupled human and natural systems are subject to economic development which, under current management structures, tends to affect natural systems and cross planetary boundaries. Hence, designing and applying conservation criteria applicable in real‐world systems where human and natural systems need to interact and sustainably coexist is essential. By recognizing the criticality of satisfying basic needs as well as the great uncertainty over the needs and preferences of future generations, we sought to incorporate conservation criteria based on minimal human impact into economic evaluation. These criteria require the conservation of environmental conditions such that the opportunity for intergenerational welfare optimization is maintained. Toward this end, we propose the integration of ecological–biological thresholds into decision making and use as an example the planetary‐boundaries approach. Both conservation scientists and economists must be involved in defining operational ecological–biological thresholds that can be incorporated into economic thinking and reflect the objectives of conservation, sustainability, and intergenerational welfare optimization.  相似文献   
2.
Abstract: High‐latitude coral reefs (HLRs) are potentially vulnerable marine ecosystems facing well‐documented threats to tropical reefs and exposure to suboptimal temperatures and insolation. In addition, because of their geographic isolation, HLRs may have poor or erratic larval connections to tropical reefs and a reduced genetic diversity and capacity to respond to environmental change. On Australia's east coast, a system of marine protected areas (MPAs) has been established with the aim of conserving HLRs in part by providing sources of colonizing larvae. To examine the effectiveness of existing MPAs as networks for dispersal, we compared genetic diversity within and among the HLRs in MPAs and between these HLRs and tropical reefs on the southern Great Barrier Reef (GBR). The 2 coral species best represented on Australian HLRs (the brooding Pocillopora damicornis and the broadcast‐spawning Goniastrea australensis) exhibited sharply contrasting patterns of diversity and connectedness. For P. damicornis, the 8‐locus genetic and genotypic diversity declined dramatically with increasing latitude (Na= 3.6–1.2, He= 0.3–0.03, Ng:N = 0.87–0.06), although population structure was consistent with recruitment derived largely from sexual reproduction (Go:Ge= 1.28–0.55). Genetic differentiation was high among the HLRs (FST[SD]= 0.32 [0.08], p < 0.05) and between the GBR and the HLRs (FST= 0.24 [0.06], p < 0.05), which indicates these temperate populations are effectively closed. In contrast for G. australensis, 9‐locus genetic diversity was more consistent across reefs (Na= 4.2–3.9, He= 0.3–0.26, Ng:N = 1–0.61), and there was no differentiation among regions (FST= 0.00 [0.004], p > 0.05), which implies the HLRs and the southern GBR are strongly interconnected. Our results demonstrate that although the current MPAs appear to capture most of the genetic diversity present within the HLR systems for these 2 species, their sharply contrasting patterns of connectivity indicate some taxa, such as P. damicornis, will be more vulnerable than others, and this disparity will provide challenges for future management.  相似文献   
3.
The side-effects of pesticides on predatory mites have been investigated at various levels and international teams (e.g., the IOBC/wprs Working Group “Pesticides and beneficial organisms”) have selected a few species of predatory mites occurring in Central and Northern Europe as representative for such studies. Key biocontrol species occurring in Southern Europe have received much less attention. Kampimodromus aberrans is the most important predator of herbivorous mites in South-European vineyards treated with selective pesticides. The impact of pesticides on K. aberrans populations has been studied in field conditions whereas few toxicological tests have been conducted in the laboratory because of difficulties in rearing this species. A method for rearing K. aberrans in the laboratory has recently been set up allowing toxicological studies to be conducted. In this paper, a toxicological method to assess the effects of pesticides on K. aberrans is described and the effects of insecticides frequently used in European vineyards on two K. aberrans strains are reported. These strains were collected from vineyards treated with organophosphates. Insecticides characterized by different modes of action were selected for trials. Among these, etofenprox and spinosad were classified as harmful to predatory mites. Chlorpyrifos reduced predatory mite fecundity, and was classified as moderately harmful for both strains. The toxicity of thiamethoxam and flufenoxuron varied with the strain (low to moderate). Indoxacarb and methoxyfenozide appeared to be harmless or slightly harmful. Implications of this study for adopting IPM tactics with a reduced risk for K. aberrans are discussed.  相似文献   
4.
Abstract

Oil products are widely used in orchards and on grapevine as pesticides, or adjuvants to pesticides. We aimed to get information on the efficacy of formulated rape seed oil against phytophagous mites in grapevine and its effect on predatory mites. Formulated rape seed oil (TELMIONR) from the Temmen GmbH, Germany was used in field trials at 0.5% and 1 %.

For phytophagous mites TELMIONR had an efficacy of 90,1% and 91,2% for 05% and for 1%, respectively. For Phytoseiidae there was no side effect at 0.5% and 1%. For Tydeiidae there was no side effect at 0.5% and a moderate toxicity (43.1%) at 1%. On the basis of our results TELMIONR seems to fit well into Integrated Pest Management or Organic Production in grapevine.  相似文献   
5.
Radioactive contamination affects soil organisms and causes profound structural rearrangements in soil zoocenoses, which are manifested in the decreased species diversity of invertebrate communities and low relative abundance of large soil invertebrates. However, these communities gradually recover their initial structure. The soil biota near the epicenter of an underground nuclear explosion performed 30 years ago in Perm oblast has been studied to reveal specific structural features of the soil macro- and microfauna. Its structural diversity is considered with regard to such components as species (taxonomic) composition, the structure of dominance, and the ratio of ecological and trophic groups.__________Translated from Ekologiya, No. 3, 2005, pp. 171–179.Original Russian Text Copyright © 2005 by Kolesnikova, Taskaeva, Krivolutskii, Taskaev.  相似文献   
6.
Nature reserves (NR) are the cornerstone of biodiversity conservation. Over the past 60 years, the rapid expansion of NRs in China, one of the world's megadiverse countries, has played a critical role in slowing biodiversity loss. We examined the changes in the number and area of China's NRs from 1956 to 2014 and analyzed the effect of economic development on the expansion of China's NRs from 2005 to 2014 with linear models. Despite a continuing increase in the number of NRs, the total area of China's NRs decreased by 3% from 2007 to 2014. This loss resulted from downsizing and degazettement of existing NRs and a slowdown in the establishment of new ones. Nature reserves in regions with rapid economic development exhibited a greater decrease in area, suggesting that downsizing and degazettement of NRs are closely related to the intensifying competition between economic growth and conservation. For example, boundary adjustments to national NRs, the most strictly protected NRs, along the coast of China's Yellow Sea, a global biodiversity hotspot with a fast-growing economy, resulted in the loss of one-third of the total area. One of the most important ecosystems in these NRs, tidal wetlands, decreased by 27.8% because of boundary adjustments and by 25.2% because of land reclamation. Our results suggest conservation achievement, in terms of both area and quality, are declining at least in some regions in the Chinese NR estate. Although the designation of protected areas that are primarily managed for sustainable use has increased rapidly in recent years in China, we propose that NRs with biodiversity conservation as their main function should not be replaced or weakened.  相似文献   
7.
A species is not native outside its native range, but native range is not precisely defined. The invasion literature contains wide discussion of the core concepts such as naturalization, invasiveness, and ecological impact, but the concept of native range has received so little attention that a formal definition does not exist. I considered, among other impediments to a formal definition of native range, the sometimes arbitrariness of the spatial and temporal limits assigned to native range. Broad questions that remain include whether invasion theory can be used to define the native range for species without non-native ranges.  相似文献   
8.
Host specificity of mites with respect to different species of small mammals in forest ecosystems was studied. The preferences of some parasites for certain host species differed from those described previously. In some cases, most parasites preferred to feed on the species that were most numerous in a certain biogeocenosis, rather than on their specific hosts. Conversely, other species of mites fed mostly on their specific hosts, irrespective of their low abundance, thus manifesting close connections with these mammals. Two mite species, Myonyssus dubinini and M. rossicus, were found in the study region for the first time.  相似文献   
9.
Abstract: Achieving multiple conservation objectives can be challenging, particularly under high uncertainty. Having agreed to limit seahorse (Hippocampus) exports to sustainable levels, signatories to the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) were offered the option of a single 10‐cm minimum size limit (MSL) as an interim management measure for all Hippocampus species (≥34). Although diverse stakeholders supported the recommended MSL, its biological and socioeconomic implications were not assessed quantitatively. We combined population viability analysis, model sensitivity analysis, and economic information to evaluate the trade‐off between conservation threat to and long‐term cumulative income from these exploited marine fishes of high conservation concern. We used the European long‐snouted seahorse (Hippocampus guttulatus) as a representative species to compare the performance of MSLs set at alternative biological reference points. Our sensitivity analyses showed that in most of our scenarios, setting the MSL just above size at maturity (9.7 cm in H. guttulatus) would not prevent exploited populations from becoming listed as vulnerable. By contrast, the relative risk of decline and extinction were almost halved—at a cost of only a 5.6% reduction in long‐term catches—by increasing the MSL to the size reached after at least one full reproductive season. On the basis of our analysis, a precautionary increase in the MSL could be compatible with sustaining fishers' livelihoods and international trade. Such management tactics that aid species conservation and have minimal effects on long term catch trends may help bolster the case for CITES trade management of other valuable marine fishes.  相似文献   
10.
The social spider mites (Acari: Tetranychidae) of Stigmaeopsis weave dense nests on the underside of host leaves. Four species occur on the leaves of bamboo in Japan: Stigmaeopsis longus, S. celarius, S. takahashii and S. saharai. We initially reconfirmed the occurrence of distinct variation in nest size among the species. Based on the hypothesis that this variation plays a role in protecting the spider mites from predators, we looked at the behavior of the natural enemies that occur on the host plants along with members of Stigmaeopsis. We found considerable variation in the ability of nests to protect the spider-mite eggs. The smallest nests protected the eggs against three predators, whereas the largest nests protected the eggs against only one predator species. So, decreases in nest size increased egg defense. Thus we concluded that nest-size variation reflects a strategy for reducing predation.Communicated by D. Gwynne  相似文献   
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