关键词： LIRIODENDRON tulipifera   BIOLOGICAL control of insects   INSECT pest control   BIGNONIACEAE   ERIOPHYIDAE  

摘要： The article presents some of the promising biological control agents against the invasive African tulip tree, Spathodea campanulata Beauv. (Bignoniaceae), in some Pacific Islands countries like Papua New Guinea, Fiji and Samoa. Among the West Africa arthropods which are potential agents are the Paradibolia coerulea Bryant (Chrysomelidae) flea-beetle, the Bunia pagnana (Drake) (Tingidae) sap-sucking bug, and the Colomerus spathodeae Carmona (Eriophyidae) leaf- and shoot-galling mite.

关键词： amino acids   BEF-China   choice experiment   formicidae   HPLC chemical analysis  

摘要： Aims Plants with extrafloral nectaries(EFNs)are common in tropical and subtropical habitats and,despite many other arthropods also forage for EFN,most studies solely focused on the defense mutualisms between EFN plants and *** study aims at a quantitative assessment of the entire arthropod community that visits EFN trees to compare visitor communities between different tree species to disentangle the mechanisms that may drive EFN visitor community *** also test for tree diversity effects on EFN visitors,as it is unknown if local tree species richness relates to the abundance and species richness of arthropods foraging for *** We sampled EFN-visiting arthropods in the experimental tree species richness gradient of the BEF-China Experiment,the currently largest forest diversity experiment in the world,and tested if tree species richness affects EFN visitors and if visitor community composition differs between EFN tree *** a second step,we analyzed the EFN of Ailanthus altissima and Triadica cochinchinensis,the two EFN tree species with highest visitor abundance,for sugars and amino acids(AA)to test if tree species-specific differences in nectar chemistry translate to differing visitor ***,we conducted a choice experiment using different artificial nectar solutions to test if nectar quality affects foraging decisions of ants,the most frequent EFN visitors in our study *** Findings EFN trees in young successional forests in subtropical South-East China are visited by a diverse assemblage of arthropods including ants,beetles,flies,and *** ants accounted for about 75%of all individuals,non-ant visitors were by far more species *** abundance and species richness declined with increasing tree species richness,suggesting a resource dilution effect,because plots with more tree species had proportionally less EFN tree individuals and thus lower nectar *** altissima and ***

关键词： arthropod herbivore damage   feeding guilds   forest canopy   generalist herbivores   leaf biomass   resource dilution   specialist herbivores   tree species richness   tree phylogenetic diversity  

摘要： Aims Plant diversity has been linked to both increasing and decreasing levels of arthropod herbivore damage in different plant *** far,these links have mainly been studied in grasslands or in artificial tree plantations with low species ***,most studies provide results from newly established experimental plant communities where trophic links are not fully established or from stands of tree saplings that have not yet developed a ***,we test how tree diversity in a species-rich subtropical forest in China with fully developed tree canopy affects levels of herbivore damage caused by different arthropod feeding *** We established 27 plots of 30×30 m *** plots were selected randomly but with the constraint that they had to span a large range of tree diversity as required for comparative studies in contrast to sample *** recorded herbivore damage caused by arthropod feeding guilds(leaf chewers,leaf skeletonizers and sap feeders)on canopy leaves of all major tree *** Findings Levels of herbivore damage increased with tree species richness and tree phylogenetic *** effects were most pronounced for damage caused by leaf *** the two diversity measures were highly correlated,we additionally found a significant interaction between them,whereby species richness increased herbivory mostly at low levels of phylogenetic *** species with the lowest proportion of canopy leaf biomass in a plot tended to suffer the highest levels of herbivore damage,which is in contrast to expectations based on the resource concentration *** results are in agreement with expectations of the dietary mixing hypothesis where generalist herbivores with a broad spectrum of food plants benefit from increased resource diversity in tree species-rich forest patches.

关键词： Biodiversity and ecosystem function   Host specialization   Plant species richness   Sustainable forest management   Trophic interactions  

摘要： Stand diversification is considered a promising management approach to increasing the multifunctionality and ecological stability of forests. However, how tree diversity affects higher trophic levels and their role in regulating forest functioning is not well explored particularly for (sub)tropical regions. We analyzed the effects of tree species richness, community composition, and functional diversity on the abundance, species richness, and beta diversity of important functional groups of herbivores and predators in a large-scale forest biodiversity experiment in south-east China. Tree species richness promoted the abundance, but not the species richness, of the dominant, generalist herbivores (especially, adult leaf chewers), probably through diet mixing effects. In contrast, tree richness did not affect the abundance of more specialized herbivores (larval leaf chewers, sap suckers) or predators (web and hunting spiders), and only increased the species richness of larval chewers. Leaf chemical diversity was unrelated to the arthropod data, and leaf morphological diversity only positively affected oligophagous herbivore and hunting spider abundance. However, richness and abundance of all arthropods showed relationships with community-weighted leaf trait means (CWM). The effects of trait diversity and CWMs probably reflect specific nutritional or habitat requirements. This is supported by the strong effects of tree species composition and CWMs on herbivore and spider beta diversity. Although specialized herbivores are generally assumed to determine herbivore effects in species-rich forests, our study suggests that generalist herbivores can be crucial for trophic interactions. Our results indicate that promoting pest control through stand diversification might require a stronger focus on identifying the best-performing tree species mixtures.

关键词： PREDATION (Biology)   BEETLES   SPATIO-temporal variation   POPULATION dynamics   FOREST ecology  

摘要： Resolving linkages between local-scale processes and regional-scale patterns in abundance of interacting species is important for understanding long-term population stability across spatial scales. Landscape patterning in consumer population dynamics may be largely the result of interactions between consumers and their predators, or driven by spatial variation in basal resources. Empirical testing of these alternatives has been limited by the lack of suitable data. In this study, we analyzed an extensive network of spatially replicated time series to characterize the local and regional processes affecting spatio-temporal dynamics of a tree-killing bark beetle (Dendroctonus frontalis or SPB) and its key predator (Thanasimus dubius) across the southeastern United States. We first used a mechanistic model to evaluate factors affecting the stability of 95 predator-prey time series and then conducted spatial analyses to evaluate scale dependence in the factors affecting the geographical patterning of this system. Across the region, population fluctuations of both species were correlated in space beyond 400 km but there was notable spatial variation in the deterministic and stochastic processes influencing forest-scale (local) fluctuations. Time series analyses indicated that local dynamics of SPB and T. dubius are not cyclical. Instead, the abundance of T. dubius responded almost instantaneously to changes in SPB abundance. Spatial variation in long-term forest-scale abundance of both species was linked most strongly to the abundance of pine habitat indicating a stronger role for resource availability in SPB population dynamics than top-down effects. Our results are consistent with other studies indicating that animal populations tend to be synchronized in space via spatially correlated processes such as weather;yet local dynamics tend to be linked to smaller-scale host patterns. Our study provides a rare empirical assessment of how local processes scale up to produce la

关键词： grazing   Great Plains   oak savannas   regeneration   Quercus macrocarpa Michx  

摘要： Oak savanna remnants contribute substantially to the biodiversity of graminoid-dominated landscapes in the Great Plains Region. Most of these ecologically important ecosystems have either been altered or lost altogether since the arrival of Europeans in the early to mid-1800s. Changes in land use have been accompanied by reduced oak regeneration, which may be attributable to grazing and other management practices. At present, numbers of surviving oak seedlings are insufficient for sustaining the recruitment of oaks into savanna overstory strata. Herbivore exclosures were used to distinguish sources of mortality in first-year bur oak (Quercus macrocarpa) seedlings to determine the impacts of large mammalian herbivores, small mammals, and drought on oak regeneration in savanna remnants in Custer County, Nebraska. Results suggested an uncertain future for extant oak savannas on private land in central Nebraska. Seedlings without exclosures exhibited 97% mortality over the first growing season, and 100% mortality was observed during the subsequent dormant season in seedlings without exclosures that had survived the growing season. Although drought and small mammals contributed to overall oak seedling mortality, cattle and deer impacts were the leading causes of mortality in seedlings without exclosures. Trampling, grazing, and browsing may compromise efforts to restore and sustain these ecologically valuable ecosystems. However, effects of these factors may be reduced through management involving exclosures and limiting grazing to seasons when young oaks are less susceptible to damage.

关键词： Conservation   forest management   habitat variables   tracks  

摘要： We examined the influence of tree thinning on the abundance of mammals in a Japanese larch Larix kaempferi plantation in Mt Gariwang, Pyeongchang, South Korea. In 2014 and 2015, from April to October, we recorded the presence of tracks as a proxy for abundance, for the following seven mammalian species: Korean hare Lepus coreanus, raccoon dog Nyctereutes procyonoides, Siberian weasel Mustela sibirica, Eurasian badger Meles meles, water deer Hydropotes inermis, roe deer Capreolus pygargus, and wild boar Sus scrofa. We also assessed how the intensity of tree thinning affected vegetation cover;there were significant differences in number of standing trees, basal area, coverage of vegetation layers, and number and volume of downed trees among the control, moderately thinned, and intensively thinned stands. We found significant differences in the abundance of tracks among the stands for three mammal species. In four mammal species, the abundance of track was significantly correlated with volume of downed trees, coverage of ground vegetation, number of downed trees, and number of standing trees, according to stepwise analysis. The presence and abundance of mammals is linked to habitat variables and forest managers should consider how habitat modifications will affect wildlife.

关键词： Anti-cancer   Anti-inflammatory   Analgesic   Ethnopharmacology   Traditional medicines   Animal models  

摘要： Ethnopharmacological relevance: Phytochemicals with anti-oxidative and anti-inflammatory properties are known to inhibit tumour initiation, promotion and progression. Hence, there is an increasingly-convincing rationale for employing remedies containing those phytochemicals in the treatment of cancers and also as analgesic and anti-inflammatory adjuvants in therapy. The plants Garcinia kola Heckel (Clusiaceae), stem bark;Uvaria chamae P. Beauv. (Annonaceae), root;and Olax subscorpioidea Oliv. (Olacaceae), root, have been documented to be part of various indigenous anti-cancer regimens. Aim of the study: To determine if the three plants exhibit significant anti-oxidative and anti-inflammatory properties. Materials and methods: Using established models, the analgesic and anti-inflammatory activities of the three plants were investigated. Results: Pre-treatment with the plant extracts at 100, 200 and 400 mg/kg produced inhibition of writhes;G. kola and U. chamae showed no significant effect on formalin-induced pain, but O. subscorpioidea produced inhibition in both phases of the formalin test. Similarly, while G. kola and U. chamae did not produce any significant inhibitory effect in the xylene-induced ear oedema model, the oedema was significantly reduced by O. subscorpioidea pre-treatment. However, all the three plants significantly inhibited the time-dependent increase in paw circumference in the carrageenan- and formaldehyde-induced rat paw oedema tests, with peak effects observed at 400 mg/kg, 6 h after the induction of oedema, comparable in some cases to the effects of two standard drugs, the non-steroidal anti-inflammatory drug diclofenac and the anti-inflammatory antibiotic doxycycline. Conclusion: We conclude that the three plant extracts possess analgesic and anti-inflammatory properties, thus providing a scientific rationale for their inclusion in some traditional anti-cancer regimens.

关键词： 树鼩   小型哺乳动物   模式动物  

摘要： 树鼩作为一类具有潜在应用价值的新型模式动物,已越来越多地受到人们的关注。简述树鼩的形态学特征、生存环境、活动特征及研究价值。

关键词： INVERTEBRATE communities   BIOMASS   HONEY mesquite   BIODIVERSITY   INVERTEBRATES  

摘要： Effects of frequency of prescribed burning on invertebrate abundance, diversity, and biomass were investigated in a shortgrass prairie encroached by mesquite, Prosopis glandulosa Torr., at Cross Bar Management Area in Potter County, TX. Invertebrates were collected from three burn treatments (frequencies of 2-3, 4-6, and 8-12 years) by using pitfall traps in 2007 and 2008. Analysis of variance was used to compare abundance, diversity, and biomass at the order and family levels using fire frequency, season, and year as main effects. In general, the season and year had more effect on abundance, diversity, and biomass than did burn frequency. These patterns are consistent with the idea that weather has more impact than fire on invertebrate biomass in shortgrass prairie. Longer-term monitoring of the effects of fire frequency is necessary to better elucidate long-term effects of burning on invertebrate communities in mesquite-encroached shortgrass prairie.