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1.
GENERALCoNDlTloNABoUTCLI-MATECHANGEINHElLoNGJIANGPRoVINCEDtlrlngthepasscdll)()}ears(l88l-l`)8(j)ors().tllctcndenc}'ofmcanairtc111pcraturcincrcasct\ithfluctuationcl11ergcdin\ariousrcglonsofHcllonViangproxincc.Airtcmpcra-turcinl98()s-rcachcdtl1emaxil11un1uithinthcpasscdll)()y'cars.Thisphcl1ol11enonaccordcd``iththctcndenc}'ofglobalclil11ate\"ar1ni11g.Thel11eanairtc111peralurcil1tl1creccl1tl()}car(l()8()-l()8`))incrcascdb}l).6"Cascom-pal-cd\`ltl1tl1atll1tl1clbrl11er3())'carsacc…  相似文献   
2.
INTRODUCTIONIntheworldoftoday,theglobalclimatechangeanditsinfluenceonecologyhavebe-comeaveryimportantproblem,towhichmanyscientists,governnentleadersandordinarypcoplepaycloseattentionI1-'].Inl979,theWorldClimateResearchProgram(WCP)waslaiddowninthefirstworldclimatemeeting.lnl99(),thesecondworldclimatemeetingwasconvcl1edinGencva,andalltl1eexpertsagreedthattheglobalwarmlngwillbeextremelyseriousdisasterthananynatUralcalamityever.Attl1eMectingof"WorldEnvironmentandDevelopment,"holdinBrazil…  相似文献   
3.
铅、镉和铬在叶类蔬菜中的累积及对其生长的影响   总被引:68,自引:3,他引:68  
 研究结果表明: 重金属元素铅(Pb) 、镉(Cd) 、铬(Cr) 对几种叶类蔬菜生长和产量都有明显的影响, 且其影响因蔬菜种类、元素种类和浓度的不同而有很大差异, 叶用莴苣> 苋菜> 芥菜> 菜薹>蕹菜, Cr > Cd > Pb ; 不同蔬菜类型可食部位积累重金属元素的顺序为苋菜> 叶用莴苣> 菜薹> 蕹菜> 芥菜;各元素从营养液向蔬菜体内转移的迁移累积率顺序为Cd > Cr > Pb。随着各元素浓度的增大, 对蔬菜生长的影响和其可食部分的富集量随之加大。  相似文献   
4.
为研究炭化竹原纤维的特性,进一步提升竹原纤维的使用性能,拓宽竹原纤维的应用领域,采用可控电炉制备了不同炭化温度和不同保温时间条件下的炭化竹原纤维,利用全自动比表面积及孔隙度分析仪测试了炭化竹原纤维的比表面积、比孔容及平均孔径,探讨了炭化条件对其性能的影响。结果表明:随炭化温度的升高和保温时间的延长,炭化竹原纤维的比表面积、比孔容和孔径分布先增大后减小,在较优的工艺条件下,炭化竹原纤维的比表面积和比孔容最大值分别可达819.35m2/g和0.7358cm3/g,平均孔径最小可达2.0836nm。  相似文献   
5.
为研究生物刺激剂对玉米的增产提质效果,试验探讨不同生物刺激剂对玉米的产量和品质方面的影响,为鲜食玉米的优质高产栽培提供技术支撑。以鲜食玉米‘钱江糯3号’为试验品种,以3种生物刺激剂(阿美滋、美基、保康灵1号)为供试药剂,设置6个处理(阿美滋1000倍液、阿美滋1500倍液、阿美滋2000倍液、美基3000倍液、保康灵1号300倍液、清水对照),研究大田常规施肥水平下药剂对‘钱江糯3号’的经济性状、产量及品质的影响。在阿美滋1500倍液喷施下,玉米的行粒数、单穗鲜重和单穗净重、产量均最高,蛋白质含量、粗纤维含量、还原糖含量、淀粉含量均居第3位;在保康灵1号300倍液喷施下,玉米的穗粗最高,单穗鲜重、单穗净重、产量均居第2位,蛋白质含量最高,脂肪含量最低,还原糖含量居第2位。阿美滋1500倍液在增加玉米产量上是最佳选择,保康灵1号300倍液则对提升玉米品质最有效果。建议生产上将阿美滋1500倍液与保康灵1号300倍液配合施用,这对鲜食玉米的增产提质效果最好。  相似文献   
6.
Essential oils are plant-derived aromatic volatile oils, and they contain bioactive compounds that have been shown to improve poultry nutrition. In this study, we investigated the effects of oregano essential oil (OEO) on intestinal antioxidative capacity, immunity, and gut microbiota of young yellow-feathered chickens. A total of nine hundred and sixty 1-d-old female Qingyuan partridge chickens were randomly allocated to four treatment groups with six replicates of 40 birds each, and the feeding trial was lasted for 30 d. The controls were fed on a basal diet without in-feed antibiotics; the birds in the antibiotic group were fed the basal diet supplemented with 20 mg/kg virginiamycin; the remaining birds were fed the basal diet containing 150 or 300 mg/kg OEO, respectively. Dietary supplementation with 150 or 300 mg/kg OEO increased average daily feed intake (P = 0.057) and average daily gain (P < 0.05). The activities of glutathione peroxidase and total antioxidative capacity in plasma, jejuna, and ileal mucosa were increased by OEO supplementation (P < 0.05), with a trend of lower jejunal content of malonaldehyde (P = 0.062). Moreover, dietary OEO increased the content of secretory immunoglobulin A (P = 0.078) and the relative expression of Claudin 1, Mucin 2, and Avain beta-defensin 1 in ileum (P < 0.05). Sequencing data of 16S rRNA indicated that dietary OEO increased the relative abundance of Firmicutes phylum, and Clostridium and Lactobacillus genera, and decreasing that of Romboutsia. Functional analyses indicated that microbial amino sugar and nucleotide sugar metabolism, replication, and repair systems were higher in OEO groups than those of controls and antibiotic treatment. In conclusion, dietary supplementation with OEO enhanced growth performance, alleviated local oxidative stress in intestine, improved production of natural antibodies, and favorably modulated intestinal microbiota composition.  相似文献   
7.
The practice of catch-and-release fishing has been widely promoted by angling fraternities as a fisheries manage- ment tool. The aim of this investigation was to determine the physiological response of Orange-Vaal smallmouth yellowfish, Labeobarbus aeneus, to catch-and-release angling in the Vaal River, South Africa. Fish were collected using standard fly-fishing techniques, anaesthetised in clove oil and blood was drawn from the caudal vein; thereafter the fish were weighed, measured, revived and released. Blood plasma was analysed for concentra- tions of glucose, cortisol and lactate to determine the effects of angling duration, fish size and water tempera- ture. Larger fish were angled for a longer duration compared with smaller fish. Levels of glucose were affected by water temperature (influenced by time of year). Plasma glucose concentrations decreased with greater angling duration. Few individuals (n = 12) showed increased plasma cortisol concentrations. In extended-capture fish (angled for >1 min), lactate concentrations increased significantly above values for rapid-capture fish (angled for >30 s). These data suggest that catch-and-release causes physiological stress to fish, but nonetheless this practice can be a valuable fisheries management tool to ensure the sustainability of fish populations. Other factors beyond the ‘angling’ time are likely to contribute to physiological disruptions in homeostasis and therefore handling and air exposure of angled fish should be included in future catch-and–release angling studies. In addition, the longer-term impact of angling on fish health should also be determined.  相似文献   
8.
Mammalian parental investment (i.e. care of descendant offspring) is largely biased towards maternal contributions due to the specific feeding needs of mammalian offspring; however, varying degrees of paternal investment have been reported in about 10% of all mammalian species. Within the order Carnivora, paternal contribution to rearing offspring is particularly high: an estimated 32% of all studied carnivore species exhibit direct paternal care. Despite the prominence of paternal investment in carnivores, the endocrine basis of this behaviour is not well understood. This review examines the current – highly constrained – state of knowledge about the endocrine basis of carnivore paternal investment. We attempt to link changes in androgen and glucocorticoid levels with variation in direct and indirect paternal care behaviour making specific predictions regarding the way forward. Well-studied species, such as bat-eared foxes (Otocyon megalotis), dwarf mongoose (Helogale parvula) and meerkats (Suricata suricatta), where social dynamics are relatively well understood, can act as ideal model systems through which we may further investigate the endocrine basis of paternal investment in carnivores.  相似文献   
9.
沼肥施用对桃树缩叶病的防治效果   总被引:2,自引:0,他引:2  
高燕  乔慧  韩文彪  赵玉柱  陈灏 《北方园艺》2016,(10):112-115
以桃树为供试材料,研究了不同沼液稀释浓度对其缩叶病的防治效果。结果表明:喷施沼液组较对照(CK)均可不同程度降低桃树缩叶病的发生。其中以沼液稀释倍数为1/8处理的效果最好,于第3次喷施后7d,病叶率由50%降低至8%,枝条新叶平均增加5片,枝条生长了4cm,均高于其它处理;其次为沼液稀释倍数为1/4和1/16的处理,病叶率分别由45%降低至10%和52%降低至15%。  相似文献   
10.
温度是影响云厚朴提取物稳定性的主要因素,本研究考察云厚朴提取物的热稳定性。采用高效液相色谱法,测定云厚朴SFE-CO2(二氧化碳超临界流体萃取)工艺萃取物中的和厚朴酚、厚朴酚在不同温度干燥时的含量变化并得出降解规律,干燥时降解为一级反应,在100 ℃降解较快。采用恒温加速实验,得出SFE-CO2萃取液中的和厚朴酚、厚朴酚室温25 ℃贮存期分别为1 125.6 h和975.7 h。在制剂生产中,云厚朴SFE-CO2萃取物不宜长时间贮存,以减少有效成分损失;由于热不稳定性,高温干燥会导致制剂质量不稳定,降低药效,应在较低温度下干燥。  相似文献   
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