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1.
应用线性倾向估计、M-K突变检验和Morlet小波函数变换分析了海南岛1961~2011年的年平均和四季平均气温、年平均最高气温、年平均最低气温、年平均和四季降水量、年降水日数、年强降水日数、年降水强度等气象要素的时间序列变化特征。结果表明:(1)近51 a来海南岛气候变暖趋势明显,通过信度为0.05的显著性水平检验,其中,年平均最低气温和冬季平均气温的上升趋势最为显著,气候倾向率分别为0.28℃/10 a和0.29℃/10 a;各气温要素均在20世纪80年代后期发生突变,并存在3~4 a和12 a时间尺度的周期变化。(2)年平均和四季降水量呈微弱的线性增加趋势,而达到暴雨等级的年强降水日数和年降水强度线性增加趋势明显,分别通过了信度为0.05和0.01的显著性水平检验。(3)四季降水量和年降水日数存在12~14 a时间尺度的周期变化,年降水量、年强降水日数和年降水强度存在8~10 a时间尺度的周期变化,同时,各个要素均叠加有周期较小的高频振荡。 相似文献
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为林下种植铁皮石斛的生产管理提供气象参考,2014-2015年对龙眼树下不同栽培方式种植的铁皮石斛茎生长和同期气象条件进行观测,分析林下气象条件对铁皮石斛茎生长的影响。结果表明:(1)龙眼树林下种植铁皮石斛茎伸长生长变化过程表现为S型生长曲线,表现为"慢——快——慢"的生长规律。龙眼树上绑扎种植铁皮石斛的茎性状均优于林下苗床种植的。(2)气象条件对铁皮石斛的茎生长有明显的影响,茎增长量和过程日平均气温、日平均气温最低值、日平均气温最高值、平均日最高气温、平均日最低气温之间存在显著的相关关系,试验林下的平均相对湿度基本保持在80%以上,基本适宜铁皮石斛的生长。在日平均气温24~30℃、日最高气温27~36℃和日最低气温20~26℃的条件下,铁皮石斛茎生长较快。生长高峰期出现时的日平均气温在27~29℃、日最高气温在32~34℃和日最低气温在24~26℃。 相似文献
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《福建热作科技》1978,(2)
根据我站气象资料分析,77/78年冬期气候有如下几个特点:1,秋凉冬暖倒春寒.秋末天高云淡,气候凉爽.77年11月10日开始,日均温降到20.0℃以下,21日后降到15.0℃以下,中下旬的平均气温比历年平均值低1.2℃—2.0℃,胶树生长受到抑制.冬季(12月—2月)温度较高,12月气温有明显回升,旬平均温度升到15.0℃—18.0℃,与历年比较,月平均气温高1.8℃,月平均最低温度高1.9℃.1月和2月温度有所下降.最冷月(1月)平均气温为12.8℃,月平均最低气温为8.8℃,都比历年平均值高O.2℃;2月份平均气温和平均最低气温均比历年平均值高0.4℃.由于12月至2月气温连续偏高,春意盎然,多数冬眠作物陆续开始活动,胶树也提早萌芽.3月初开始,天气转为阴冷潮湿,中下旬的平均气温比历年平均值低1.2℃—1.6℃,胶树物候发育受到抑制.如表—1. 相似文献
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北疆机采棉喷施脱叶剂适期与气象适宜指标研究 总被引：1，自引：0，他引：1
《棉花科学》2018,(6)
为了提高北疆机采棉的脱叶效果,并保证棉花品质和产量的下降程度最低。通过研究脱叶效果与喷施脱叶剂时气象条件的关系,以获得棉花喷施脱叶剂最适宜时间。结果表明,喷施后5至15天是脱叶剂关键期,日平均气温18℃,日最低气温15℃时,棉花脱叶率最高,脱叶率为98%～99%,但对棉花产量影响较大;日平均气温17℃,日最低气温13℃,满足这个气象条件脱叶效果较好,脱叶率达98%～99%,棉花产量和品质也都达到试验要求。石河子地区以9月10日左右把握适宜的温度条件进行喷脱叶剂是最适宜时间 相似文献
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为探索佳木斯地区冬季保管暖菜方法和不经劈堆散热、直接转为冻藏的可能必,我们于1984～1985年生产期进行了暖菜大堆积量的保管试验。保藏时间为1985年10月5日至1986年2月26日,计143天。做堆时最高气温为22℃,最低气温为-6℃,平均气温为5.85℃。堆积规格:底宽18～20m,上宽10～12m,高3.15m,堆长40～100m,堆 相似文献
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长沙地区宜用育性转换临界光长＞１３小时３０分，临界温度为连续４天日平均气温＞２４℃，或连续２天日平均气温＞３℃，或连续４天日最低气温＞２２℃，或连续３天日最低气温＞２１℃的光温型不育系，长沙地区制种，敏感期直安排在 ８月中旬，抽穗期在 ８月下旬和 ９月初；繁殖则敏感期安排在８月下旬和９月初，抽穗期在９月上、中旬。 相似文献
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农业气象条件对苦丁茶生长及产量形态的影响 总被引：4，自引：0，他引：4
采用平行观测法分析研究了苦丁茶的生长习性与农业气象条件的关系；通过相关关系模拟，建立了苦丁茶的叶片、株高、茎围生长量与农业气象条件间的数学模拟模型，得出了苦丁茶生长适宜的农业气象条件指标，研究发现苦丁茶叶片、茎转芳要受水分条件的影响，株高主要受热量条件的影响；月平均气温20.0℃以上，最低气温17℃以上，最高气温35℃以下，降水量100mm以上，雨日18d以上，空气相对湿度87％以上，土壤含水量15％－16％最适宜苦丁茶生长，最低气温小于10℃,苦丁茶嫩叶有轻微寒害现象；最高气温超过35℃，各和修生长普遍受到伤害。土壤含水量12％以下，苦丁茶出现旱害，叶片变黄，枝条干枯甚至死亡。 相似文献
10.
假眼小绿叶蝉主害峰危害趋势的预测 总被引：1，自引：0，他引：1
根据1978～1992年的资料,影响假眼小绿叶蝉第1峰(主害峰)危害趋势的主要影响因子有:冬季日平均气温在0℃及0℃以下的天数(x_1),1月份平均气温(x_2),冬季日均温的负温和(x_3),负温平均(x_4=(x_3)/(x_1))。预测方法采用加权列联表法,其历年回报的理论值完全符合实际。本文系补充和修正了作者1986年提出的预测方法,以提高预测的准确性及使用范围。 相似文献
11.
Joseph E. Laferriere Charles W. Weber Edwin A. Kohlhepp 《Plant foods for human nutrition (Dordrecht, Netherlands)》1991,41(3):277-282
Teas of plant origin traditionally consumed by the Mountain Pima of Chihuahua, Mexico, were analyzed for mineral nutritional content. Fe, Cu, Zn, Ca, and Mg composition was determined for native teas made from shoots ofTagetes lucida, T. filifolia, Elytraria imbricata, andHolodiscus dumosus, and from root xylem ofCeanothus depressus andPhaseolus ritensis. Native uses of these teas are also described. 相似文献
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Lakshman Lal 《Potato Research》1987,30(2):329-334
Summary The effects of the leaves of five plant species, one from each of the generaAmbrosia, Anemone, Eupatorium, Eucalyptus andLantana, on potato tuber moth were investigated under indigenous storage conditions at the Central Potato Research Station, Shillong
(1800 m above sea level). Their action was compared with that of a biological insecticide (spores ofBacillus thuringiensis), a chemical insecticide (carbaryl), and an untreated control. The data collected after six months storage on tuber damage,
sprout damage and the rotting indicated that the leaves ofLantana aculeata provided most protection to the tubers, reducing damage from over 70% in the check to below 5%, and sprout damage from over
45% to below 3%. Next best wasEucalyptus globulus followed byB. thuringiensis. They may be used on tubers stored for table use or for seed as they had no adverse effect on germination or on the yield
of a subsequent crop. 相似文献
14.
《Journal of Crop Improvement》2013,27(2):81-114
Summary The efficiency of N fertilizers is usually poor; often less than 50% of the applied N is taken up by the crop. This review focuses on various N fertilizers with respect to the significance of different N loss pathways, namely (i) ammonia volatilization, (ii) dinitrogen and nitrogen oxide emissions, and (iii) nitrate leaching. Further, the significance of biological N immobilization, ammonium fixation and, finally, the impact of nitrate vs. ammonium uptake on crop yield are also discussed. The reviewed literature shows that N fertilizers may differ markedly in their susceptibility to losses. There is, however, considerable scope to improve N efficiency of each N source by proper N management practices. 相似文献
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Tatiana G. Polotow Sandra C. Poppe Cristina V. Vardaris Douglas Ganini Maísa Guariroba Rita Mattei Elaine Hatanaka Maria F. Martins Eduardo F. Bondan Marcelo P. Barros 《Marine drugs》2015,13(10):6117-6137
Health authorities worldwide have consistently recommended the regular consumption of marine fishes and seafood to preserve memory, sustain cognitive functions, and prevent neurodegenerative processes in humans. Shrimp, crabs, lobster, and salmon are of particular interest in the human diet due to their substantial provision of omega-3 fatty acids (n-3/PUFAs) and the antioxidant carotenoid astaxanthin (ASTA). However, the optimal ratio between these nutraceuticals in natural sources is apparently the key factor for maximum protection against most neuro-motor disorders. Therefore, we aimed here to investigate the effects of a long-term supplementation with (n-3)/PUFAs-rich fish oil, ASTA-rich algal biomass, the combination of them, or krill oil (a natural combination of both nutrients) on baseline redox balance and neuro-inflammation indexes in cerebellum and motor cortex of Wistar rats. Significant changes in redox metabolism were only observed upon ASTA supplementation, which reinforce its antioxidant properties with a putative mitochondrial-centered action in rat brain. Krill oil imposed mild astrocyte activation in motor cortex of Wistar rats, although no redox or inflammatory index was concomitantly altered. In summary, there is no experimental evidence that krill oil, fish oil, oralgal biomass (minor variation), drastically change the baseline oxidative conditions or the neuro-inflammatory scenario in neuromotor-associated rat brain regions. 相似文献
17.
Youna Hemery Ulla Holopainen Anna-Maija Lampi Pekka Lehtinen Tanja Nurmi Vieno Piironen Minnamari Edelmann Xavier Rouau 《Journal of Cereal Science》2011
Wheat bran is a composite material made of several layers, such as pericarp, testa and aleurone. It could be fractionated into purified fractions, which might either be used as food ingredients, or serve as a starting material for extraction of bioactive compounds. The aim of this work was to evaluate the potential of using electrostatic separation as a way to obtain purified fractions from wheat bran. Ultrafine-ground bran obtained either by cryogenic grinding or by grinding at ambient temperature was used as starting material. The ultrafine bran was then charged by tribo-electrification and introduced in a chamber containing two high voltage electrodes, where bran particles were separated depending on their acquired charge, allowing positively and negatively charged fractions to be collected separately. The particle size distribution, microstructure and biochemical composition of the obtained fractions were studied. The charge of the particles was influenced by their biochemical composition: particles rich in highly branched and cross-linked arabinoxylans (pericarp) were separated from particles rich in β-glucan, ferulic acid and para-coumaric acid (aleurone cell walls). The testa and the intracellular compounds from aleurone were not highly charged, neither positively nor negatively. The most positively charged fraction represented 34% of the initial bran, and contained 62% of the ferulic acid present in the initial bran. The yield of the separation process was good (5.4% loss), and could be further increased. 相似文献
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M. I. Siri P. Villanueva M. J. Pianzzola L. Franco Fraguas G. Galván M. Acosta F. Ferreira 《Potato Research》2004,47(3-4):127-138
Summary The in vitro antimicrobial activity of extracts from accessions ofSolanum commersonii Dun. collected in the south of Uruguay was investigated against five microorganisms including the pathogenRalstonia solanacearum. A total of 30 extracts corresponding to organic and aqueous extracts were studied. Interestingly, most of the positive results
for growth inhibition were againstR. solanacearum. The extracts were also analyzed for the presence of glycoalkaloids and lectins. Six of the ten aqueous extracts showed lectin
presence and a wide variation in the type and amounts of glycoalkaloids, was found. Results indicate that there is no clear
relationship between the antimicrobial activity against the five microorganisms screened and the presence or amounts of lectins
and glycoalkaloids, traditionally regarded as possible antimicrobial metabolites in theSolanum genus, which indicates the presence of as yet unidentified antimicrobial compounds. 相似文献
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Tovar LR Olivos M Gutierrez ME 《Plant foods for human nutrition (Dordrecht, Netherlands)》2008,63(4):189-194
Pulque is made by fermenting the agave sap or aguamiel of Agave atrovirens with a whole array of microorganisms present in the environment including several lactic acid bacteria and yeasts such as
Saccharomyces cerevisiae. Ascorbic acid was determined in pulque and aguamiel, respectively. Phytase activity in lees, liquid and freeze-dried pulque was assayed by measuring the appearance of phosphate from phytate by a colorimetric method likewise phosphate from phytate
present in fresh corn tortilla was measured after in vitro incubation with pulque. Iron, zinc, calcium, magnesium and selenium contents were measured in pulque and corn tortilla as well as in nixtamalized corn flour (NCF), the latter is used to make instant tortilla, since corn provides
most of the energy as well as most of the phytate in the Mexican rural diet. Pulque showed phytase activity but much less ascorbic acid and iron than previously reported; additionally, phytase in pulque hydrolyzed most of phytate’s corn tortilla. Lees, which is mostly made of pulque’s microbiota, significantly accumulated iron and zinc but no selenium. NCF was fortified with iron by the manufacturers but
poorly blended. There were significant differences on selenium content between tortillas samples, apparently some soils in
central Mexico are selenium deficient. Moderate pulque intake appears to increase the bioavailability of iron and zinc bound by phytate in corn. 相似文献
20.
Novel food and non-food uses for sorghum and millets 总被引：4，自引：3，他引：4
Sorghum and millets have considerable potential in foods and beverages. As they are gluten-free they are suitable for coeliacs. Sorghum is also a potentially important source of nutraceuticals such antioxidant phenolics and cholesterol-lowering waxes. Cakes, cookies, pasta, a parboiled rice-like product and snack foods have been successfully produced from sorghum and, in some cases, millets. Wheat-free sorghum or millet bread remains the main challenge. Additives such as native and pre-gelatinised starches, hydrocolloids, fat, egg and rye pentosans improve bread quality. However, specific volumes are lower than those for wheat bread or gluten-free breads based on pure starches, and in many cases, breads tend to stale faster. Lager and stout beers with sorghum are brewed commercially. Sorghum's high-starch gelatinisation temperature and low beta-amylase activity remain problems with regard to complete substitution of barley malt with sorghum malt . The role of the sorghum endosperm matrix protein and cell wall components in limiting extract is a research focus. Brewing with millets is still at an experimental stage. Sorghum could be important for bioethanol and other bio-industrial products. Bioethanol research has focused on improving the economics of the process through cultivar selection, method development for low-quality grain and pre-processing to recover valuable by-products. Potential by-products such as the kafirin prolamin proteins and the pericarp wax have potential as bioplastic films and coatings for foods, primarily due to their hydrophobicity. 相似文献