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71.
In this study the authors analyse the incidence inthe airborne pollen from exotic plants that grow inthe Botanical Gardens of the University of Cagliari.It was possible to collect the pollen grains of 52 ofthe species cultivated in the Botanical Gardens, mostof which belong to the Leguminosae, the Moraceae and the Myrtaceae. Casuarinastricta Aiton of Australian origin shows the highestconcentration with 137 grains per cubic metre of air. 相似文献
72.
Summary Samples of shoots ofPistacia lentiscus carrying galls of the aphid,Aploneura lentisci, were collected at three localities in Israel.
Shoots growing near pruning scars carried more galls than elsewhere on the plant, but these galls weighed less and contained
fewer aphids (smaller clones). The proportion of empty galls increased with gall density. Crowding of galls at such sites
may be due to the early burst of buds at the time of aphid emergence from the overwintering eggs, and not to active search
for preferred sites.
Shoots bearing larger numbers of leaves carried heavier galls, which contained larger aphid clones. The position of the galled
leaf on the shoot had no effect on gall weight nor on clone size.
The physiological condition of the plant may be an important environmental (ecological) factor affecting the variation in
clone-size and in aphid morphology among galls. 相似文献
73.
Melissa Glackin 《Journal of biological education》2018,52(3):283-293
Teachers conceptualise inquiry learning in science learning differently. This is particularly evident when teachers are introduced to inquiry pedagogy within a new context. This exploratory study draws on semi-structured interviews conducted with eight pre-service secondary biology teachers following a day visit with university tutors to the Royal Botanical Gardens, Kew. Emerging findings were: first, pre-service biology teachers’ views of inquiry learning range in sophistication from simple notions of ‘learning from doing’ to complex multi-notions such as student generated questions, developing curiosity and encouraging authentic scientific practices. Second, similarly their views of inquiry learning opportunities in botanical gardens ranged from simply places that offered ‘memorable experiences’ to enabling autonomous learning due to the organism diversity and multiple climates. Pre-service teachers categorised as having unsophisticated views of inquiry learning had limited expectations of botanical gardens as productive learning environments. Third, the majority of pre-service teachers were concerned about managing inquiry learning. A tension was identified between how open-ended an inquiry activity could be whilst ensuring student focus. Further, participants were concerned about the practical management of inquiry learning. We discuss implications for teacher educators and botanical garden educators and the requirement for curriculum development and promotion. 相似文献
74.
MARIA HELENA PEREIRA‐PEIXOTO GESINE PUFAL MICHAEL STAAB CELSO FEITOSA MARTINS ALEXANDRA‐MARIA KLEIN 《Ecological Entomology》2016,41(3):241-252
1. Urbanisation and agricultural intensification cause the replacement of natural ecosystems but might also create novel habitats in urban and rural ecosystems promoting some insect communities by providing food and nesting resources. 2. This study investigated how host–natural enemy communities change in urban and rural landscapes and their transitional zone, the urban–rural interface, by using trap nests for cavity‐nesting Hymenoptera in gardens and rapeseed fields that were either isolated or paired in the urban–rural interface. 3. Host dynamics were important for natural enemy occurrence, species richness and parasitism rates, and landscape effects were evident for natural enemy variables except for the richness of bee natural enemies. The number of parasitised brood cells was at its highest in the urban–rural interface, but the highest parasitism rates of bees were observed in isolated gardens. Parasitism rates of bees were negatively affected by host abundance, while parasitism rates of wasps were positively affected. 4. Higher specialisation and lower connectivity of host–natural enemy interactions were found in paired habitats than in isolated habitats. This indicates that paired habitats comprise more specific natural enemies and vulnerable interactions, while isolated habitats comprise more generalist natural enemies, and thus interactions appear more stable. 5. These results confirm that host dynamics play an essential role in the abundance and richness of natural enemies and drive parasitism. However, high habitat heterogeneity found in the urban–rural interface can also have an effect on host–natural enemy communities. This highlights that the provisioning of resources in the urban–rural interface can benefit insect communities in these areas. 相似文献
75.
David J.MABBERLEY 《云南植物研究》2011,33(1):31-38
The history of botanic gardens in the United Kingdom is sketched out with particular reference to the Royal Botanic Gardens Kew and its changing role to meet societal requirements over 250 years. Kew's position as a modem scientific institution confronting today's environmental issues through its Breathing Planet Programme yet retaining its heritage buildings and collections is pinpointed. 相似文献
76.
针对历史园林遗产中植物景观保护面临的现存问题,从国际公约方面着手分析,指出中国古典园林营造修复的要点与相关国际宪章之间的差异,尤其是如何对待历史园林“真实性”的问题。并借助欧洲、美国、日本与中国相关案例研究,论述国内外在该方面研究实践的共性、差异及其成因。最后在分析国际同行经验基础上,结合中国历史文化背景,总结并提出了可供中国园林遗产保护与修复工作参考的经验及思想。 相似文献
77.
A novel yeast species was isolated from leaf litter of Macropanax dispermus obtained from the Cibodas Botanical Garden, West Java, Indonesia. The two strains of the species displayed typical characteristics of the genus Citeromyces. Phylogenetic analysis based on the gene sequences of the D1/D2 domains of large subunit (LSU) rDNA, internal transcribed spacer (ITS) including 5.8S rDNA, mitochondrial small-subunit rRNA gene (MtSm), and translation elongation factor-1α (EF-1α) showed that the novel strains were clearly separated from the other four existing species of the genus Citeromyces. Therefore, the two strains were proposed to represent a novel species within the genus Citeromyces, for which the name Citeromyces cibodasensis is proposed; the type strain is NBRC 110244T (= CBS 14272T?=?InaCCY703T?=?AK 01). 相似文献
78.
Dietary supplement Standard Reference Materials 总被引:1,自引:0,他引:1
A new category of Standard Reference Materials (SRMs) based on dietary supplements is under development by the National Institute of Standards and Technology (NIST), with certified values for organic constituents and selected trace elements. These materials are provided primarily for use in method development and as control materials. The SRMs will assist manufacturers of dietary supplements in characterizing raw materials for potency, authenticity, and contamination or adulteration. In addition, the SRMs will assist in assessment of consistency and quality in finished products. The goal of this ongoing effort is to provide tools to the dietary supplement industry and measurement communities that will lead to improved quality of dietary supplements, and ultimately reduce public health risks that could potentially be associated with these products. 相似文献
79.
Govindjee 《Photosynthesis research》2006,87(2):151-158
This Editorial has four goals: (1) to inform the readers of ‘Photosynthesis Research‘ about the past of the ‘Historical corner’; which began 20 years ago; (2) to encourage photosynthesis researchers and historians of science to contact me for publishing papers of historical interest; these include: (a) Obituaries and Tributes; (b) historical papers on current and past discoveries and controversies; (c) history of research in specific laboratories, or in specific countries, or at specific conferences; (d) Personal perspectives (not discussed any further); (3) to encourage researchers not to discard, but to save correspondence and data of their discoveries for the future historians by donating them to their Archives, when appropriate (not discussed any further); and (4) to reinforce to the readers that the concept of two-light reaction and two-pigment system was already there in 1959. I mention here three key papers presented at the IXth International Botanical Congress, held at Montreal Canada (in August, 1959) prior to the famous April 9, 1960 paper by Robert Hill and Fay Bendall on the ‘Z-scheme’ of photosynthesis, that was based on thermodynamic and energetic considerations.
★ This Historical corner Editorial is dedicated to Bessel Kok (1918–1978). 相似文献
80.
Welmoed A. Out 《Vegetation History and Archaeobotany》2008,17(1):25-39
Brandwijk-Kerkhof (ca. 4600 to 3630 cal b.c.) is a Neolithic site, located on a river dune in the Dutch Rhine/Maas river area. The natural vegetation and human impact
upon it have been investigated by analysis of pollen and macroremains from four cores that are located at increasing distances
up to 20 m from the site. The relationship between the strength of human impact on the vegetation and the distance of the
cores from the river dune has been investigated as well. The results show that the natural vegetation on top of the river
dune consisted of deciduous woodland, while in the surrounding wetlands alder carr and eutrophic marsh vegetation dominated.
Human impact of limited strength resulted in more open and disturbed vegetation. There is no correlation between the strength
of the evidence of human impact in the pollen diagrams and the distance of the cores from the river dune. The evidence for
presence of crop plants from the cores is compared with evidence from the excavation. The first presence of crop plants from
ca. 4200 b.c. onwards corresponds with data from other Dutch wetland sites. Large-scale local crop cultivation cannot however be demonstrated.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献