青海锡铁山矿区铅、锌的植物地球化学特征及其与矿的关系

 通过青海锡铁山铅、锌矿区植物群落和植物中铅,锌含量特征的调查研究表明：该区植被为荒漠植被类型。矿带上的植物群落与非矿带上的相比较,群落中种属数目更少,覆盖度更低,植物生长更低矮。植物灰分中的锌含量(平均)为125.9—1144ppm。膜果麻黄(Ephedra przewalskii)含量最高,变化范围最大,为86.11—5871.88ppm。植物中的铅含量为31.32—1129.6ppm。黑柴(Sympegma regelii)含量较高,变化最大,平均为746ppm,极值为14.3—5561.70ppm。在矿带上含量最高,非矿带对照区含量最低。植物及其生长的土壤中金属元素含量之间的关系,无论是铅还是锌含量都有很好的线性关系。膜果麻黄、黑柴、优若藜(Eurotia ceratoides)和中亚紫菀木(Asterothamnus centrali-asiaticus)等植物相关系数均达显著相关水平(α≤0.05)。 这在植物地球化学勘探上是非常有用的。例如中亚紫菀木和琵琶柴(Reaumuria soongorica)中铅的植物地球化学异常,准确地圈出了铅、锌矿的位置,衬度高,异常范围与矿化区基本吻合。     

Characteristics of Plant Communities and Element Contents in Plants at Mengentaoligai Ag,Pb, Zn Mine area in Inner Mongolia

The types of plant communities in Mengentaoligai mine area are disscussed. Arenaria juncea, densely grown in the phytocommunities of the mineralized zone, is found closely related to the presence of Pb and Zn mineral deposits. Analytical results of seven element contents (in ash) for 34 species (or part of plant) show that: levels of element contents in sequence in. the plants are Fe>Mn > Zn > Pb > Cu > Ni>Co; variable ranges of element contents in the plants are Pb, Zn>Fe,Mn> Cu> Co > Ni; and variable ranges of Pb, Zn contents in the same species at different sites are respectively larger than that among species. For example, Pb and Zn contents of Arenaria juncea, l145ppm and 3087ppm respectively, are the highest; the difference among Pb contents of Ulmus macrocarpa, Arenaria ?uncea and PotentiUa chinensis at different sites are more than 10 folds. The difference of Co and Ni contents in the species is less than two to one- Striking correlation is found between elements in plants and in soils, such as the Pb and Zn contents between leaves and twigs of Ulmus macrocarpa, twigs of Prunus sibirica, Artemisia halodendron and soils (lrl≤α 0.05 or≤α 0.01). It is found that Pb and Zn phytogeochemical anomalies, correlate closely with Pb and Zn mining deposits. In addition, analysis of principal component was conducted among seven elements contents of 14 species (or part of plant) in the mineralized zone and 12 species in the unmineralized zone.