共查询到20条相似文献，搜索用时 15 毫秒
1.
Nilsson Anna L. K. Skaugen Thomas Reitan Trond L’Abée-Lund Jan Henning Gamelon Marlène Jerstad Kurt Røstad Ole Wiggo Slagsvold Tore Stenseth Nils C. Vøllestad L. Asbjørn Walseng Bjørn 《BMC ecology》2020,20(1):1-12
While nitrogen and carbon stable isotope values can reflect ecological segregation, prey choice and spatial distribution in seabirds, the interpretation of bulk stable isotope values is frequently hampered by a lack of isotopic baseline data. In this study, we used compound-specific isotope analyses of amino acids (CSIA-AA) to overcome this constraint and to study interspecific differences, seasonal and historical changes in trophic positions of five seabird species, three penguins and two petrels, from a sub-Antarctic seabird community. CSIA-AA allowed comparing trophic positions of seabirds with temperate and polar distributions. Gentoo and Magellanic penguins had the highest trophic positions during the breeding season (3.7 and 3.9), but decreased these (2.9 and 3.3) during the feed-up for moult. Intra-specific differences were also detected in Thin-billed prions, where carbon isotope values clearly separated individuals with polar and temperate distributions, both in the breeding and interbreeding periods. Thin-billed prions that foraged in polar waters had lower trophic positions (3.2) than conspecifics foraging in temperate waters (3.8). We further investigated historical changes by comparing museum samples with samples collected recently. Our pilot study suggests that Rockhopper penguins, Magellanic penguins and Thin-billed prions with temperate non-breeding distributions had retained their trophic levels over a 90–100 year period, while Gentoo penguins and Thin-billed prions with polar non-breeding distributions had decreased trophic levels compared to historical samples. In contrast, Wilson’s storm-petrels had slightly increased trophic levels compared to samples taken in 1924–1930. We applied compound-specific stable isotope analyses across a range of contexts, from intra-specific comparisons between stages of the breeding cycle to inter-specific seabird community analysis that would not have been possible using bulk stable isotope analyses alone due to differences in isotopic baselines. 相似文献
2.
Recep Karakaş 《Paddy and Water Environment》2017,15(4):919-930
The birds of Kabakl? Pond and its near surrounding were surveyed between October 2014 and December 2015 periods. During the study period, 105 bird species that belong to 12 orders and 34 families were detected and represented. Among these species determined, 17 of them certainly, 19 probably and 11 possibly breed in the area, while 58 of them are wintering or transitory migrating birds for the area. Among the recorded species, seven are globally threatened, while 20 are threatened for Turkey without least concern species. Obtained information suggests that this small artificial area has a great importance for many bird species related to habitat that have. Habitat preferences of species were analysed, and it was determined that the most preferred habitats are pond (water surface), wooded and agricultural zones, respectively. Also, the maximum bird number obtained during April and December, while maximum bird species richness observed during April. Results suggest that artificial ponds can be important for birds as feeding, resting and breeding area due to rapidly decline in natural wetland areas. Effective protection of the area requires the prevention of illegal hunting, fishing, human disturbance and pasturing. Also, in order to extend the existing reed and meadow areas, convenient plantation of natural plants at around of pond has a critic role for waterfowl. 相似文献
3.
Andrew C. Huang Christine A. Bishop René McKibbin Anna Drake David J. Green 《BMC ecology》2017,17(1):29
Background
Long-distance migratory birds in North America have undergone precipitous declines over the past half-century. Although the trend is clear, for many migrating species underpinning the exact causes poses a challenge to conservation due to the numerous stressors that they encounter. Climate conditions during all phases of their annual cycle can have important consequences for their survival. Here, using 15 years of capture-recapture dataset, we determined the effects of various climate factors during the breeding, wintering, and migrating stages on the annual survival of a western yellow-breasted chat (Icteria virens auricollis) population breeding in southwestern Canada.Results
El Niño effects over the entire annual cycle had little influence on the annual apparent survival of yellow-breasted chats. However, we found evidence that wind conditions during migration, specifically average westerly wind speed or the frequency of storm events, had significant adverse effects on adult annual apparent survival. In comparison, precipitation levels on wintering ground had little to no influence on adult annual apparent survival, whereas growing degree days on the breeding ground had moderate but positive effects.Conclusions
In the face of climate change and its predicted impacts on climate processes, understanding the influence of weather conditions on the survival of migrating birds can allow appropriate conservation strategies to be adopted for chats and other declining neotropical migrants.4.
The objectives of this study were to investigate physiological and psychological responses to the rustling sound of Korean
traditional silk fabrics and to figure out objective measurements such as sound parameters and mechanical properties determining
the human responses. Five different traditional silk fabrics were selected by cluster analysis and their sound characteristics
were observed in terms of FFT spectra and some calculated sound parameters including level pressure of total sound (LPT),
Zwicker’s psychoacoustic parameters — loudness(Z), sharpness(Z), roughness(Z), and fluctuation strength(Z), and sound color
factors such as ΔL and Δf. As physiological signals, the ratio of low frequency to high frequency (LF/HF) from the power spectrum
of heart rate variability, pulse volume (PV), heart rate (HR), and skin conductance level (SCL) evoked by the fabric sounds
were measured from thirty participants. Also, seven aspects of psychological state including softness, loudness, sharpness,
roughness, clearness, highness, and pleasantness were evaluated when each sound was presented. The traditional silk fabric
sounds were likely to be felt as soft and pleasant rather than clear and high, which seemed to evoke less change of both LF/HF
and SCL indicating a negative sensation than other fabrics previously reported. As fluctuation strength(Z) were higher and
bending rigidity (B) values lower, the fabrics tended to be perceived as sounding softer, which resulted in increase of PV
changes. The higher LPT was concerned with higher rating for subjective loudness so that HR was more increased. Also, compression
linearity (LC) affected subjective pleasantness positively, which caused less changes of HR. Therefore, we concluded that
such objective measurements as LPT, fluctuation strength(Z), bending rigidity (B), and compression linearity (LC) were significant
factors affecting physiological and psychological responses to the sounds of Korean traditional silk fabrics. 相似文献
5.
The objectives of this study were to investigate the effect of frictional sound of Korean combat uniform fabrics on the human responses of ANS and to relate them to the mechanical properties of fabrics in order to find out the way to reduce frictional sound of combat uniform fabrics. Three different frictional sounds of combat uniform fabrics were selected by cluster analysis and their sound characteristics were calculated using Sound Quality System. Ten participants’ ANS responses such as heart rate (HR), the ratio of LF/HF, skin conductance level (SCL), and pulse volume (PV) were measured during presenting the frictional sound as stimuli. Mechanical properties were measured by KES-FB system. Response differences (ANS responses after stimuli — those before stimuli) of HR and LF/HF significantly were positive to all of the fabric sounds, while the differences of pulse volume (PV) were negative. This phenomenon explains that sympathetic nerve system of all participants stimulated and they might feel nervous or bad with the frictional sound of fabric. WC, MMD, SMD and weight of fabric were negatively correlated with ANS, but RT, B and RC were positively correlated. They appeared to be influential factors affecting ANS responses. 相似文献
6.
JA Drew CL Buxman DD Holmes JL Mandecki AJ Mungkaje AC Richardson MW Westneat 《BMC ecology》2012,12(1):15
ABSTRACT: BACKGROUND: The effective management and conservation of biodiversity is predicated on clearly defined conservation targets. Species number is frequently used as a metric for conservation prioritization and monitoring changes in ecosystem health. We conducted a series of synoptic surveys focusing on the fishes of the Bootless Bay region of Papua New Guinea to generate a checklist of fishes of the region. Bootless Bay lies directly south of Port Moresby, the capital of Papua New Guinea, and experiences the highest human population density of any marine area in the country. Our checklist will set a baseline against which future environmental changes can be tracked RESULTS: We generated a checklist of 488 fish species in 72 families found in Bootless Bay during a two-week sampling effort. Using incident-based methods of species estimation, we extrapolate there to be approximately 940 fish species in Bootless Bay, one of the lowest reported numbers in Papua New Guinea. CONCLUSIONS: Our data suggest that the Bootless Bay ecosystem of Papua New Guinea, while diverse in absolute terms, has lower fish biodiversity compared to other shallow marine areas within the country. These differences in faunal diversity are most likely a combination of unequal sampling effort as well as biophysical factors within Bootless Bay compounded by historical and/or contemporary anthropogenic disturbances. 相似文献
7.
Kinh Bac Dang Benjamin Burkhard Felix Müller Van Bao Dang 《Paddy and Water Environment》2018,16(4):767-781
Land use change due to the development of agriculture and community-based tourism has resulted in an increase in natural hazards (e.g. erosion and landslides) that affect sustainability in the Sapa mountainous area in northern Vietnam. Natural hazard regulating ecosystem services have protected the local people from the destruction of their villages, goods and natural resources, especially in the rainy season. However, it is difficult to identify which kinds of anthropogenic constructions support a co-production of regulating services in human-influenced social–ecological systems and in which specific types of land use and land cover the supply of such services takes place, especially in heterogeneous mountainous areas. Therefore, this research attempts to (1) distinguish between the potential and actual use (flow) of natural hazard regulating ecosystem services and (2) understand how soil erosion and landslide regulating ecosystem services can contribute to a sustainable management of different ecosystems, especially in rice fields and forest areas. Two models (InVEST for soil erosion, Analytic Hierarchy Process for landslide analysis) were used to analyze and map the contributions of natural versus anthropogenic components for regulating natural hazards in Sapa. The results show the incoherent distribution of erosion regulating services and low capacities of landslide regulating services in areas that have seriously been affected by human activities, especially forestry and agricultural development. The contribution of rice ecosystems to soil erosion mitigation is higher than in the case of landslides. Nevertheless, one-third of the area of paddy fields in the case study area have “no” capacity to supply natural hazard regulating ecosystem services and should therefore be re-forested. 相似文献
8.
亚麻品种资源对枯萎病的抗性评价 —06 总被引：1，自引：0，他引：1
利用亚麻枯萎病病圃,对508份国内外亚麻品种资源进行了抗枯萎病的鉴定和评价,按照参试品种较统 一感病对照发病率的降低率,把抗枯萎病程度划分为高抗(HR) 、中抗(MR) 、低抗(LR) 、低感(LS) 、中感(MS)和高 感(HS)共6个级别。各个级别的品种资源数分别为45、38、64、92、112 和157;分别占试验资源总数的8. 9%、 7. 5%、12. 5%、18. 1%、22. 1%和30. 9%。高、中抗资源共计16. 4%。筛选出的高抗和中抗枯萎病资源中有41份 属于首次报道,其中包括13份国外引进品种、7份国内地方品种和21份国内育成品种,一些重点抗源已成功地应 用于亚麻抗枯萎病育种实践。 相似文献
9.
This research presents the results of the study of seeds quality of two Polish native species of the genus Betula L. (Betula pendula Roth and Betula obscura Kotula), growing on the semi-natural (low human activities) and anthropogenic (high human activities) habitats. In this study the generative phase has been investigated to find differences between studied taxa and try to find out why population of B. obscura is very rare. In this research we have checked the quality of the seeds from B. obscura and B. pendula and test the survival of seedlings sowed into the ground researched in laboratory conditions. Results of germination capacity shown significant difference between trees from the anthropogenic and semi-natural sites; the energy capacity indicated significant difference between trees: B. pendula and B. obscura from all study areas. Mixed-model ANOVA/MANOVA for seedlings growth showed statistically important effects of factors (species, area, months). The results show that B. obscura grows better on the anthropogenic habitats than B. pendula, but the latter had more of the fully developed seeds and higher germination and seeds energy capacity. 相似文献
10.
2020年我国玉米生物学研究继续保持高速发展态势,创新研究成果不断涌现,我国玉米研究团队在国际顶尖学术期刊发表的文章数量稳步提升。在89个SCI或SCIE期刊上发表玉米生物学研究论文369篇,相对于2019年的366篇略有增加,其中,5年平均影响因子超过5.0的高水平论文有86篇,比2019年的83篇增加了3篇,论文质量稳步提升。369篇论文的研究内容涉及玉米基因组学、玉米株型相关性状遗传调控、玉米子粒发育遗传调控、玉米雌穗和雄穗穗性状遗传调控、玉米抗生物和非生物胁迫遗传调控、玉米养分利用遗传调控和玉米育种技术研究等。本文概括性地综述2020年我国科学家在玉米生物学研究领域取得的代表性研究成果。 相似文献
11.
通过对水松各分布区实地调查,从生殖生物学、生态因子胁迫、人为干扰和遗传多样性等方面探讨水松濒危的主要原因。研究表明：水松原始的生物学特性制约了其生存规模,对生境的高要求影响了其持续繁衍,人为干扰引起的生境破碎化和过度砍伐所导致的个体数量下降是其濒危的直接因素,较低的遗传多样性水平是其濒危的内在因素。针对水松濒危的原因和现状,提出在种群规模大、遗传多样性高的分布地设立保护点,对生境退化、规模较小的种群采取迁地保护措施,并通过人工繁育幼苗扩大种群规模。 相似文献
12.
David G. Fisher Kenneth L. Deahl Maxwell V. Rainforth 《American Journal of Potato Research》2002,79(4):281-293
Horizontal resistance (HR) was assessed as a strategy to reduce potato defoliation by the Colorado potato beetle (CPB). Hybrids amongSolanum tuberosum varieties grown in Iowa were first evaluated with a detached leaflet feeding bioassay. Beginning in 1998, resistance was increased annually over three years by intermating and selecting the most resistant l%–2% of each generation of 300–400 plants using the bioassay. When C (= mg leaf tissue consumed* neonate larva-1 over 48 h) was measured for the 1% most-resistant genotypes of all generations grown side by side in 2000, it ranged from 6.1 mg* larva-1 in the parents to 2.3 for progeny of the F3 generation compared to 2.7 in ND2858-1, a resistant check. Field trials in Wisconsin showed less defoliation in the F1 and F2 selected genotypes than in the parents. A second breeding program using moreS. tuberosum parents with greater genetic diversity, and much larger breeding populations, resulted in significantly faster accumulation of resistance, further suggesting that recurrent mass selection is effective. Foliar glycoalkaloid analyses revealed low levels of solanine and chaconine in the F3 selections; no leptines or leptinines were detected. Because the parents wereS. tuberosum varieties in which vertical resistance to CPB is unknown, and because the resistance to feeding from parents to the F3 resistant plants was linear and gradual while ranging from initially very low to considerably higher in the third year, horizontal resistance is strongly implicated. The development of a significant degree of resistance after three rounds of breeding using relatively small breeding populations suggests that HR can be developed from varieties ofSolanum tuberosum lacking initial high levels of resistance to CPB. 相似文献
13.
14.
大豆是世界上重要的豆类作物,是人类植物性蛋白和食用油的主要来源.大豆花叶病毒(soybean mosaic virus,SMV)是大豆重要的病原物之一,广泛分布于世界各大豆产区,严重影响大豆的产量和品质.目前尚无有效的化学药剂可以防治大豆花叶病毒病,培育抗病品种是最经济、安全、有效的途径.然而,传统的抗病育种周期漫长,... 相似文献
15.
育种技术的研究和发展有力地推动了优良品种的更新换代。本文通过对2017-2021年间全球玉米育种技术领域相关专利数据挖掘与分析,重点从主要专利布局区域、权利人、技术分布、热点分布以及高价值专利等方面分析发展动态与竞争态势。分析表明,美国是玉米育种技术的专利领先国,专利申请和高价值专利分别占全球的40%和69%,专利研发机构为跨国种业企业集团为主。我国玉米育种技术专利申请排名全球第3,研发机构以科研院所、大学为主,但高价值专利偏少,仅为美国的5.86%。提出要增强玉米育种技术研发与专利布局等3方面建议。 相似文献
16.
Anthony T. Slater Noel O. I. Cogan Brendan C. Rodoni Hans D. Daetwyler Benjamin J. Hayes Brittney Caruana Pieter E. Badenhorst German C. Spangenberg John W. Forster 《Potato Research》2017,60(3-4):337-352
A conventional potato breeding strategy uses targeted outcrossing, followed by phenotypic recurrent selection over a series of generations to identify improved cultivars. This paper reviews recent research in Australia aimed at improving the efficiency of such breeding. To develop marker-assisted selection (MAS) for traits of interest, our initial targets were qualitative disease resistances for potato cyst nematode (Globodera rostochiensis Ro1), Potato virus Y and Potato virus X. We undertook a cost analysis comparison between MAS and conventional screening, confirming that MAS would be cost-effective within a breeding programme. Then, as the majority of target traits are quantitative in nature, we also looked at methods to address these traits, including progeny testing and a quantitative genetic analysis technique to develop estimated breeding values (EBVs). We found the markers were useful for detecting the disease resistance characters, while the EBVs improved the analysis of the complex traits. Using a combination of MAS, EBVs and conventional screening methods, we then designed a breeding scheme for rapid selection of cultivars with multiple desirable traits, reducing the breeding cycle from over 10 to 4 years. We then explored the factors that will affect the application of genomic selection in potato and investigated strategies to incorporate genomic selection in potato breeding, as we found that it would accelerate genetic gain as the breeding cycle can be reduced to 1 year. Improvements in computational power are also flowing on to research capabilities such as sequencing, high-throughput phenotyping and data analysis, which will accelerate germplasm improvement and breeding. High-throughput phenotyping facilities are being developed that include automated glasshouse systems equipped with imaging sensors and in-field high-throughput phenotyping systems with sensors mounted on ground- or aerial-based vehicles. Using these technological improvements in phenotypic and genotypic analysis will reduce the breeding cycle in a cost-effective manner and means that we can now breed differently. 相似文献
17.
《Field Crops Research》1999,60(1-2):143-163
Of all the elements, the most important to consider in terms of food-chain contamination are arsenic (As), cadmium (Cd), mercury (Hg), lead (Pb) and selenium (Se). Where soils are enriched in these elements, it is usually through the agricultural, industrial or urban activities of man, except for Se where high concentrations in soil are often derived from high-Se parent rock materials. The propensity for plants to accumulate and translocate these contaminants to edible and harvested parts depends largely on soil and climatic factors, plant genotype and agronomic management. Elevated As intake, especially of inorganic As, is most likely to arise from high-As drinking water than from ingestion of food. Cadmium and Se are of the greatest concern in terms of terrestrial food-chain contamination, with the former element receiving most attention. Worldwide, the probability of insufficient Se in the human diet exceeds that of toxicity, with deficiency usually associated with monotonous vegetarian diets in areas with Se-deficient soils. Excessive human intake of Cd is of concern as this element accumulates over a lifetime in the body, with impairment of kidney function being the main adverse effect. Cadmium inputs to soil in fertilizer, biosolids, soil amendments and atmospheric deposition often exceed outputs in crops and drainage waters, so that Cd concentrations in many agricultural soils are slowly increasing. However, evidence for increases in Cd concentrations in crops over time is contentious, as is the evidence for human health problems due to low-level Cd contamination of the food chain. Adverse health effects due to Cd intake have been manifest only in situations of gross soil contamination, with a predominantly rice-based diet, where soil–plant and plant–human transfer of Cd would have been enhanced. Human feeding studies have indicated that food Cd bioavailability is dependent on Fe nutrition, and animal studies have indicated that Zn, Ca, P and other elements and food constituents (e.g. fiber, phytate) affect Cd bioavailability. While plant breeding and agronomic management can minimize soil–plant transfer of Cd, and maximize concentrations of antagonists to Cd assimilation in humans, it remains important that inputs of this metal to soil be minimized. 相似文献
18.
Background
In colonially breeding birds, the ability to discriminate between individuals is often essential. During post-fledging care, parents have to recognize their own offspring among many other unrelated chicks in the breeding colony. It is well known that fledglings and food-provisioning parents of many bird species use contact calls to convey their identity. These calls are also often used as hunger-related signals of need in young birds. Here, we investigate how such calls incorporate signals of need and at the same time act as reliable indicators of each chick's identity. 相似文献19.
J. G. Kozub D. R. Lynch G. C. Kozub L. M. Kawchuk D. K. Fujimoto 《American Journal of Potato Research》2000,77(2):95-101
Using a desktop database management system (DBMS), a relational database system was developed to replace outdated systems for data storage, retrieval and summary in a potato breeding research program. The new system allows for easy and efficient access, storage and interrelation of potato data, and automated reporting functions to support presentation and analysis requirements of the research program. DBMS tools and programmed functions provide summary information pertaining to such areas as potato plant genealogy and progeny performance in early selection, regional adaptation and disease resistance trials. Database structures have been implemented to facilitate the collection and verification of new data, interface to a hand-held data collection computer, and transfer report data and charts to standard word processing and presentation software. The concepts and techniques used in the construction of this database system can be applied to other potato and plant breeding programs 相似文献