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41.
INTRoDUCTIoNAnthasbeenusedasmedicineandhealthprotectionproductsfora1ongtime-Theant(PolyrhachisvicinaRoger)ismostincommon.TheyaremainlylivinginGuangxiProvince.Theyareablack,irri-tateacidityanddelicatefragranceinsects.ThereisakindofantinWandaMountain,Daxing'anMountain,andXiaoxing'anMountain.Itisabig(aboutmorethanl-ocmlong),strongandnonpollutioninsect.alotofbigandblackantswerecollectedfromWandaMountain.Itwasappraisedbyantexpertstobeantfami1yandantcategory.ItwasnamedFormicacuniculariaLa… 相似文献
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连香树人工幼林群落营养元素含量、积累分配和循环 总被引:11,自引:1,他引:11
研究了 1 0年生连香树人工群落 8种营养元素的含量、积累分配和循环。主要结论是 :( 1 )连香树营养器官中各种元素的平均含量顺序为Ca>N >Al>K >Mg>P >Fe >Mn。 ( 2 )元素量在各营养器官的分配顺序为根 >叶 >去皮干 >皮 >枝 ,各元素含量顺序为Ca>N >K >Al>Mg>P >Fe >Mn。 ( 3)连香树群落 8种元素的吸收量、存留量和归还量分别是 72 9 82kg·hm- 2 a- 1 、2 0 6 72kg·hm- 2 a- 1 和 52 3 1 0kg·hm- 2 a- 1 。 ( 4) 51 2 %的归还总K量靠降水淋溶归还 ,其余元素总归还量的 55 7%~ 96 5%靠凋落物归还。Fe、Al归还量的 4 1 3%和 4 4 3%通过死根归还。 ( 5) 8种元素的利用系数、归还比和周转期分别为 0 2 3~ 0 54、0 57~ 0 82和 2 2 6~7 63。文中改进了降水淋溶归还的算法 ,提出了群落归还系数、积累系数和吸收系数 ,讨论了落叶树种元素生物循环的算法 相似文献
45.
福建比利时杜鹃叶片矿质营养含量的研究 总被引:8,自引:0,他引:8
分别用凯氏定氮法、钼蓝比色法、火焰光度法和原子吸收分光光度法,对市场上生长良好的福建比利时杜鹃花叶片N、P、K、Ca、Mg、Fe、Mn、Cu、Zn的含量进行了测定,并运用数理统计方法和SPSS软件对测定结果进行了分析.结果表明,未成熟叶片中各营养元素含量分别为N 32.9 g/kg, P 4.6 g/kg, K 22.6 g/kg, Ca 23.9 g/kg, Mg 3.4 g/kg,Fe 123.3 mg/kg,Mn 249.2 mg/kg, Cu 27.5 mg/kg,Zn 163.2 mg/kg.活性Fe的含量为12.3 mg/kg.N、P、K的比例为1∶0.14∶0.69.成熟叶片中营养元素含量分别为N 28.0 g/kg,P 4.2 g/kg1,K 24.2 g/kg,Ca 24.9 g/kg,Mg 3.6 g/kg,Fe 265.5 mg/kg,Mn 354.3 mg/kg,Cu 19.8 mg/kg,Zn 142.3 mg/kg.活性Fe的含量为18.0 mg/kg.N、P、K的比例为1∶0.15∶0.87.该分析结果可供其他地区生长不良的杜鹃进行营养诊断时参考,以改善杜鹃生长不良的状况. 相似文献
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Functional compatibility between thirteen tropical fruit trees (Afzelia africana Smith., Adansonia digitata L., Aphania senegalensis Radlk., Anacardium occidentale L., Cordyla pinnata (Lepr. ex A. Rich.) Milne-Redhead, Dialium guineensis Wild., Landolphia heudelottii A.DC., Sclerocarya birrea (A.Roch.) Hochst., Saba senegalensis (A. DC.) Pichon and four reference hosts Balanites aegyptiaca (L.) Del., Parkia biglobosa (Jacq.), Tamarindus indica L. and Zizyphus mauritiana Lam.) and two arbuscular mycorrhizal fungi (AMF) (Glomus aggregatum Schenck and Smith emend. Schenck and Glomus intraradices Schenck and Smith), was investigated. Marked differences were found between them in terms of mycorrhizal formation, root colonization, relative mycorrhizal dependency (RMD) and phosphorus concentrations in shoot tissues. A. africana, L. heudelottii and S. senegalensis did not form symbiotic associations, and the growth of A. africana decreased following mycorrhizal inoculation, while L. heudelottii and S. senegalensis showed no dependency. In contrast, A. digitata, A. senegalensis, A. occidentale, B. aegyptiaca and S. birrea were well colonized with AMF, but did not significantly increase in biomass production. Five fruit trees did, however, show dependency by a positive interaction with G. aggregatum, the most effective AMF. Z. mauritiana was found to be very highly dependent (RMD > 75%), T. indica was highly dependent (50–75% RMD), and D. guineensis, P. biglobosa and C. pinnata were moderately dependent (25–50% RMD). Phosphorus absorption probably contributed to this dependency more than the absorption of potassium. These results indicate that some tropical fruit trees do derive benefits from AM inoculation, while others do not.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
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49.
Altitudinal gradient incorporates multiple resource gradients, which vary continuously in different fashions. It is important
to study the mountain floristic patterns along altitudinal gradients, which reveal the regular pattern of the flora along
the environmental gradients, the changing trend of biodiversity patterns along the altitudinal gradient, and relevance of
biological fitness. To explore the compositional characteristics and ecological significance of floristic patterns along altitudinal
gradient in China National Nature Reserve of Dawei Mountain in the southeast of Yunnan Province, field investigations have
been made to the flora along the two routes of the southwest slope and the northeast slope of the said reserve, including
a vertical vegetation transect. Meanwhile, further investigations have also been made to the flora of Dawei Mountain, which
has been accounted for in the literature, as Flora Yunnan, The Seed Plant in Yunnan, and so on. The structural characteristics of the flora and the altitudinal distribution pattern of its floristic components
were analyzed. By applying systematic cluster analysis, the altitudinal position of the dividing line of floristic changes
along altitudinal gradient was detected, and the effects of the montane climate on the vertical variation of floristic composition
were studied. Conclusions were put forward. This paper can be summarized as follows: (1) The obvious boundary that differentiates
tropical floristic elements is located at the altitude of approximately 1,500 m; it is reasonable to stipulate the boundary
line between tropical rain forests and the evergreen broad-leaved forests. (2) The vertical vegetation spectrum made by cluster
analysis shows that humid rain forests are below 700 m a.s.l, montane rain forests are between 700 and 1,500 m, monsoon evergreen
broad-leaved forests are between 1,300 and 1,800 m, and montane mossy evergreen broad-leaved forests are above 1,800 m a.s.l.
Nonrepresentative montane mossy dwarf forests (above 2,100 m) in the area are distributed in windward sides and in barren
land on the mountain slopes.
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Translated from Acta Phytoecologica Sinica, 2005, 29(6): 894–900 [译自: 植物生态学报] 相似文献
50.
火炬松人工林养分体内转移与内循环研究 总被引:4,自引:0,他引:4
对江苏省下蜀林场火炬松人工林 (15年生 )地上部分养分体内转移和内循环特点进行了初步研究 ,结果表明 :(1)在体内养分转移中 ,叶的贡献最大 ,N、P、K和Mg元素的平均转移量均大于枝和干 ;地上部分养分N、P、K和Mg元素的转移率分别为 44 9% ,34 5 % ,2 0 8%和 30 7%。 (2 )地上部分养分归还量N、P、K、Ca和Mg元素分别 5 5 787,6 13,2 6 70 ,70 79和 2 0 30kg·hm- 2 ·a- 1 分别占需要量的 36 6 7% ,44 6 5 % 5 5 3% ,78 0 2 %和 42 84% ;地上实际消耗土壤中的养分量N、P、K、Ca和Mg分别为 2 2 48,2 13,4 6 4,2 6 98和 7 41kg·hm- 2 ·a- 1 ,分别占吸收量的 2 3 99% ,2 2 76 % ,11 84% ,2 4 32 %和 2 1 0 9%。 (3)与当地的杉木林和次生栎林相比 ,该火炬松人工林养分利用率高 ,并处于养分消耗阶段。 相似文献