Ubugunov V.L., Merkusheva M.G. Content, accumulation and distribution lead in alluvial soils and flood-plain communities within Western Transbaikalian // Ecology of Siberia the Far East and the Arctic / Int. conf. (Sept. 5-8). – Tomsk, 2001. – P.289.

 

CONTENT, ACCUMULATION AND DISTRIBUTION

LEAD IN ALLUVIAL SOILS AND FLOOD-PLAIN COMMUNITIES

WITHIN WESTERN TRANSBAIKALIAN

Ubugunov V.L., Merkusheva M.G.

Institute Of General And Experimental Biology SB RAN,

670047, Ulan-Ude, Sakhyanova st., 6, E-mail: ioeb@bsc.buryatia.ru,

Ph.: (301-2) 335065, fax: (301-2) 330134

Section " Rational  using of nature and planning of territory development,  technologies of nature saving .

The oral report

 

The are large territories of Western Transbaikalian, used as hayfields and pastures, in the river flood-plains. Therefore the study of grass fodder value of flood-plain communities is of great interest in regions, where cattle breeding is highly developed. One of criteria of grass fodder value estimation is Pb content in it.

Purpose of investigation – study of lead content, accumulation and distribution in soil – root mass – overground phytomass system of flood-plain (бескильницево-ползунково-осокового, бескильницевого-лапчаткового, чиевого и осоково-разнотравного) communities, growing on the alluvial marshy, meadow and meadow-soddy soils and alluvial wet solonchak.

The Pb contents in alluvial soils varied in limits 0.8-13.2. Pb distribution in the soil structure was uneven and correlated with the contents of physical clay (r = 0.46).

Root mass of flood-plain communities is equaled to 82-92% of total phytomass.  Lead content in root mass is equaled to 8.4-15.4 mg/kgs, in oveground phytomass – 1.2-5.2 мг/kg or 1.7-7.9% from total stocks.

Accumulation coefficient, that showed root system protective functions of flood-plain phytocenoses, tantamount to 2.8-4.8. The species specificity of plant-dominants lead accumulation is established. So, highest quantity of the element is accumulated by бескильница тонкоцветная and осока вздутая, (5.2 mg/kgs), lowest - by лисохвост вздутый and чий блестящий (1.2 mg/kgs).

In that way it’s established, that alluvial soils of Western Transbaicalin didn’t contain toxic  concentration of Pb. Overground phytomass of flood-plain communities didn’t accumulate superfluous and exceeding limit admissible concentration of the element. Major factors of lead accumulation and distribution are in soils – the contents of physical clay, in plants - barrier functions of underground mass – overground phytomass system and species specificity of flood-plain phytocenoses.