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11.
  1. The mangrove horseshoe crab, Carcinoscorpius rotundicauda, has divergent populations between the east and west coasts of Peninsular Malaysia, with the southern coast acting as a land barrier. The actual position of such a genetic break along Peninsular Malaysia as well as the connectivity status of the southernmost C. rotundicauda populations with east and west coast populations remain unexplored, however.
  2. The aim was to investigate the genetic diversity and structure of C. rotundicauda populations from the west (Kuala Sepetang in State Perak), east (Balok in State Pahang), and southern (Pendas in State Johor) coasts of Peninsular Malaysia. Haemolymph samples from adult C. rotundicauda specimens (n = 152) and eggs from their freshly deposited nests (n = 190) were collected monthly (from January 2016 to January 2017) for the sequencing of mitochondrial cytochrome c oxidase subunit I (COI).
  3. Gene isolates of C. rotundicauda from the present study were compared with National Center for Biotechnology Information (NCBI) GenBank sequences to cover most of the range of the species in Asia. A neighbour-joining tree strongly supported two clades, separating the west-coast populations from the south- and east-coast populations, with further substructure patterns.
  4. Both haplotype network and barrier analyses revealed a genetic break within the Strait of Malacca instead of the southern tip of Peninsular Malaysia. The southernmost samples from the Strait of Johor formed a haplotypic diverse gene pool that appeared only as a subclade of the eastern populations. In a detailed haplotype network of 347 individuals, individuals with similar COI sequences indicate connectivity between C. rotundicauda on the east and C. rotundicauda on south and south west of Peninsular Malaysia.
  5. Overall, the genetic break between C. rotundicauda populations is better explained by the convergent ocean currents and available mangrove habitats on the west coast (i.e. Strait of Malacca), rather than the point of the Malay Peninsula acting as a land barrier alone.
  相似文献   
12.
The main goal of this article is to identify and classify institutional barriers which prevent the use of urban green spaces (UGS) at three levels: availability (whether a UGS exists), accessibility (whether it is physically and psychologically accessible, e.g., not fenced off), and attractiveness (whether it is attractive enough for potential users to visit). We reviewed the impacts on UGS provision exerted by different actors (individuals, formal and informal groups, community councils, city authorities, national governmental and non-governmental organizations), along with the relevant institutional foundations of those impacts. As a result, we identified and classified the different barriers for which these actors are responsible in the case of fifteen UGS types in our case study city, Lodz (Łódź) in Poland. The main barriers at different levels concern conflicting interests, physical barriers (private green spaces), and the lack of funds, together with legal and governmental failures (public green spaces). These barriers result from the different actors’ mandates or lack thereof. Our analysis has implications for the operationalization of UGS availability, accessibility and attractiveness, and, in particular, for mapping UGS and setting the relevant indicators and thresholds for UGS availability, accessibility and attractiveness.  相似文献   
13.
14.
《Scientia Horticulturae》2005,105(2):213-221
Young leaf samples were taken from susceptible and resistant pear varieties in June and August for 2 years in 2000 and 2001 and were analyzed for phenolic compounds by using thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC) after artificial inoculation with Erwinia amylovora. The distribution of spots in relation to phenolic compounds on TLC plates showed differences in resistant varieties compared to susceptible ones. The number of spots in resistant varieties was generally higher than the other group. Some spots were peculiar for distinguishing resistant and susceptible ones. Similarly, on HPLC dendograms, mean arbutin value was higher in the resistant group than the susceptibles both in 2000 and 2001. Additionally, arbutin content was found to be higher than chlorogenic acid content both in resistant and susceptible varieties.  相似文献   
15.
Coelioscopy is a surgical technique in which small incisions are made into the coelomic cavity through which specific instrumentation is inserted to evaluate the internal structures within. For this reason, coelioscopy must be considered a less-invasive surgical method than traditional abdominal surgery. This study was aimed at evaluating and adapting the general coelioscopic principles of the technique to teleosts (10 European eels [Anguilla anguilla]). All the examined fish were anaesthetized with tricaine methanesulfonate solution. The coelioscopic procedures were performed with a rigid, 30° offset, 1.9-mm diameter endoscope connected to a portable video system. The results confirm that coelioscopy represents an imaging technique with high sensitivity in evaluating the coelomic organs in European eels.  相似文献   
16.
This study describes a radiographic survey of the anatomical development of the distal extremity of the manus in the donkey from 0 to 2 years of age. The right distal limb of 10 donkey foals, born in the spring of 2012, underwent radiographs every month for the first 6 months of age and every 3 months during the following 18 months. Latero‐medial radiographs with and without barium marker at the coronary band and dorso‐palmar radiographs with both front feet in weight bearing were obtained. The distal physis of the third metacarpal bone and the proximal physis of the proximal phalanx (phalanx proximalis) were closed at the mean age of 18.6 months. The distal physis of the proximal phalanx appeared as a clear radiolucent line at 2 weeks of age and was still subtly visible in some donkeys at 24 months. The proximal physis of the middle phalanx (phalanx media) was closed at the mean age of 16.7 months. The distal physis of this phalanx was visible at birth, but closed at 4 days. The distal phalanx (phalanx distalis) was triangular at birth. At the age of 20–21 months, the palmar processes (processus palmares) were both developed. The navicular bone (os sesamoideum distalis) was developed at the mean age of 9 months. The proximal sesamoid bones (ossa sesamoidea proximalia) were seen in continuously development during the 24 months. It seems that the physes in the distal extremity of the manus in the donkey close at an older age than the physes in the horse.  相似文献   
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18.
Forest structure and productivity was investigated in a 12-year-old Rhizophora mucronata Lam. plantation at Gazi Bay, Kenya. Sampling was carried out in 22, 10 m × 10 m quadrats laid along belt transects perpendicular to the waterline. Within each quadrat all trees with stem diameter greater than 2.5 cm were identified, position marked and counted. Vegetation measurements included tree height (m), canopy cover (%) and stem diameter measured at 1.3 m above the ground (D130); from which were derived basal area (m2/ha); stand density (stems/ha) and biomass (t/ha). Information regarding composition and distribution of juveniles was derived using linear regeneration sampling (LRS). The replanted forest had a stand density of 5132 stems/ha; with a mean canopy height and stem diameter of 8.4 ± 1.1 m (range: 3.0–11.0 m) and 6.2 ± 1.87 cm (range: 2.5–12.4 cm), respectively. The total juvenile density was 4886 saplings per hectare; 78.6% of which constituted the parental canopy. The standing biomass for the 12-year-old R. mucronata plantation was 106.7 ± 24.0 t/ha, giving a biomass accumulation rate of 8.9 t/(ha year).  相似文献   
19.
从吸附膜的设计、采样装置的设计和分析方法三个方面系统介绍了梯度扩散薄膜技术(DGT)在土壤和沉积物介质中原位高分辨研究的方法学,并回顾了DGT自诞生以来在根际土壤和沉积物中原位高分辨应用所取得的重要研究成果,最后探讨了DGT在原位高分辨研究中的发展前景。DGT技术在沉积物和土壤中对污染物微界面机制的原位高分辨率研究,能够揭示控制重金属污染的关键过程,为针对性地做出管理控制方案提供了重要理论支持,从而推动我国对土壤、沉积物污染的防治和粮食安全的控制。  相似文献   
20.
Cities around the world are increasingly expanding their sustainability agendas and adopting urban green and blue infrastructure planning as a strategy to become more resilient, healthy and sustainable. However, the development of urban greening governance often lacks a holistic vision that considers social inequities within the planning, implementation and management of green and blue spaces. Further, gender inequities have been a specific dimension particularly overlooked in urban greening planning, despite gender concerns gaining increasing political relevance in recent years. In this research, we assessed the extento to which social and gender equity are being considered in urban greening plans and projects at the local level. We chose Barcelona (Spain) as main case study due to its pioneering role in implementing crosscutting equity and gender policies at the municipal level. Building on document analysis and semi-structured interviews with key stakeholders, we examined how social justice and gender are understood and operationalized in practice, from the design phase to implementation and maintenance of greening projects. Our findings suggest a shift in the role of urban greening which evolved from an ornamental role to a multifunctional vision of greening and is recently incorporating equity and inclusivity concerns. We identified three action areas of inclusive, gender-sensitive urban green planning practices: first, the incorporation of inclusivity and care as guiding visible values to recognize multiple needs of city residents; second, urban design for different uses and perceptions of greenspaces, particularly in relation to accessibility and autonomy; and third, the awareness and expertise from municipal staff vis-à-vis the consideration of social and gender equity in green planning and participatory approaches. Finally, we provide practical examples of the strategies that the City of Barcelona is implementing in each area and discuss some challenges and limitations, including what we identify as ad hoc intersectional greening.  相似文献   
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