Field survey and sampling were conducted in October
2008. 22 plant species from 13 families species encountered
were recorded and their relative abundances were
estimated visually and described as 1–5 (from very rare to
very abundant). The mineland was divided into seven
subareas in terms of the dominant plants colonized and
mineland purpose (Fig. 1): (1) A natural restoration area
(soil sampling site: S1), the soil surface has slumped in
many plots due to the impact of groundwater while mining.
Many natural Rhizoma imperatae and Arthraxon bispidus
were collected; (2) The area around smelt factory was set
as S2. The wastewater from smelt factory was drained into
a small river which is about 10 m apart from the factory.
The Phragmites communis Trin and Acorus calamus L.
were collected on the shoreside; (3) The area polluted by
wastewater from a drainage tube located on the hill adjacent
to La Qiong village (S3), the wastewater flowed along
the hill and led to form a zone about 300 m2 with grey and
black sludge. Only Pteris vittata and Rosa laevigata were
collected near the zone; (4) The flat ground lies at the foot
of the hill above (S4). A dense shrub belt is canopy closed,
where Equisetum ramosissimum and P. vittata were collected.
(5) Tailing dump (S5), there four types of plant,
Taraxcum mingolicum, Ficus tikoua, Miscanthus floridulus
(Labill) Warb and Ageratum conyzoides were gathered. (6)
Hole tailing dump (S6), ounce tailings still remained. The
Flos buddlejae and Pteris multifida were collected. (7)
Artificial agricultural restoration field (S7). The Brassica
chinensis, Zea mays L. and Arachis hypogaea L. were
collected. For each sampling site, surface soils (0–20 cm)
were sampled separately. The 3–5 subsamples were
merged into one single sample and three parallel samples
were collected. Samples of dominant plants for each area,
including some agronomic species, were collected. All soil
and plant samples were sealed with polythene bags and
transported into laboratory.
Soil samples were air-dried, ground and passed through
100 mesh plastic sieve. Plant samples were gently rinsed
with deionized water. Dried plant tissues were ground into
fine powder. Soil samples were digested with concentrated
HCl ? concentrated HNO3 ? HF ? HClO4 (10:5:5:3,
v/v) and plant tissues digested with concentrated
HNO3 ? HClO4 (10:3–5, v/v). The total metal concentrations
(Pb, Zn, Fe, Mn, Cu, and Cr) in the digestates were
then determined by PE-AA700 Atomic Absorption Spectrophotometer.
Analytical limits of detection were
0.03 mg L-1 for Zn, 0.06 mg L-1 for Cu and Mn,
0.1 mg L-1 for Fe and 0.2 mg L-1 for Pb and Cr. The
analytical recovery range of six kinds of metal was 98.7%–
106.4%, which was measured up to the analytical demand
(QA/QC). Data with replicates were presented as
mean ± standard deviation (SD).
2008. 22 plant species from 13 families species encountered
were recorded and their relative abundances were
estimated visually and described as 1–5 (from very rare to
very abundant). The mineland was divided into seven
subareas in terms of the dominant plants colonized and
mineland purpose (Fig. 1): (1) A natural restoration area
(soil sampling site: S1), the soil surface has slumped in
many plots due to the impact of groundwater while mining.
Many natural Rhizoma imperatae and Arthraxon bispidus
were collected; (2) The area around smelt factory was set
as S2. The wastewater from smelt factory was drained into
a small river which is about 10 m apart from the factory.
The Phragmites communis Trin and Acorus calamus L.
were collected on the shoreside; (3) The area polluted by
wastewater from a drainage tube located on the hill adjacent
to La Qiong village (S3), the wastewater flowed along
the hill and led to form a zone about 300 m2 with grey and
black sludge. Only Pteris vittata and Rosa laevigata were
collected near the zone; (4) The flat ground lies at the foot
of the hill above (S4). A dense shrub belt is canopy closed,
where Equisetum ramosissimum and P. vittata were collected.
(5) Tailing dump (S5), there four types of plant,
Taraxcum mingolicum, Ficus tikoua, Miscanthus floridulus
(Labill) Warb and Ageratum conyzoides were gathered. (6)
Hole tailing dump (S6), ounce tailings still remained. The
Flos buddlejae and Pteris multifida were collected. (7)
Artificial agricultural restoration field (S7). The Brassica
chinensis, Zea mays L. and Arachis hypogaea L. were
collected. For each sampling site, surface soils (0–20 cm)
were sampled separately. The 3–5 subsamples were
merged into one single sample and three parallel samples
were collected. Samples of dominant plants for each area,
including some agronomic species, were collected. All soil
and plant samples were sealed with polythene bags and
transported into laboratory.
Soil samples were air-dried, ground and passed through
100 mesh plastic sieve. Plant samples were gently rinsed
with deionized water. Dried plant tissues were ground into
fine powder. Soil samples were digested with concentrated
HCl ? concentrated HNO3 ? HF ? HClO4 (10:5:5:3,
v/v) and plant tissues digested with concentrated
HNO3 ? HClO4 (10:3–5, v/v). The total metal concentrations
(Pb, Zn, Fe, Mn, Cu, and Cr) in the digestates were
then determined by PE-AA700 Atomic Absorption Spectrophotometer.
Analytical limits of detection were
0.03 mg L-1 for Zn, 0.06 mg L-1 for Cu and Mn,
0.1 mg L-1 for Fe and 0.2 mg L-1 for Pb and Cr. The
analytical recovery range of six kinds of metal was 98.7%–
106.4%, which was measured up to the analytical demand
(QA/QC). Data with replicates were presented as
mean ± standard deviation (SD).
Tidak ada komentar:
Posting Komentar