Phytostabilization for Sustainable End-Use of Arsenic-Rich Mine Tailings in the Victorian Goldfields, Australia - Environmental Contamination: Health Risks and Ecological Restoration - page 438

plough..Ten.eucalypt.seedlings.were.planted.at.1.5.m.spacing.along.the.rip.
line.and.cereal.rye.was.seeded.in.parallel.bands.alongside.the.rip.to.provide.
a.cover.nurse.crop.to.reduce.wind.blasting.
The.survival,.establishment,.and.growth.of.trees.and.grasses.were.moni-
tored. in. parallel. with. physical.and. chemical.changes.occurring. in.the.sul-
idic.tailings.determined.from.sampled.cores..Field.plots.were.excavated.to.
measure.the.extent.of.root.proliferation.by.tree.species.
Results
Establishment of Perennial Pastures
Native Grasses
Native. grass. establishment. was. generally. poor. on. all. treatments. in. the.
Proto-TERF.trial..Of.the.three.species,.only. M. stipoides .was.initially.able.to.
establish..No.seedlings.of.the.other.two.species.were.observed.in.December.
2001,. 5. months. after. seeding.. After. 10. months,. the. exotic. grass. cover. was.
very.dense.preventing.reliable.estimation.of.emergence.of.the.native.species..
Germinability.of.seed.of. A. caespitosa .and. T. triandra .was.<10%.and.was.the.
main.reason.for.lack.of.establishment.of.these.species..Competition.from.the.
exotic.species.may.have.also.limited.growth.of.the.native.grasses..Only.the.
coverage. of. M. stipoides . was. monitored. and. the. heterogeneity. of. variance.
of. measurements. was. considerable.. Data. for. consecutive. May. assessments.
of. M. stipoides . are. summarized. in. Figure. 20.3b.. The. treatments. with. oxide.
waste.plus.biosolids.resulted.in.the.greatest.cover;.however,.there.were.very.
large.standard.errors..Estimated.percentage.cover.in.the.oxide.plus.low.bio-
solids.treatment.was.36.7%.±.20.5%.in.2002.and.32.3%.±.31.3%.in.2003,.while.
the.equivalent.coverages.for.the.oxide.plus.high.biosolids.were.45.0%.±.18.9%.
and. 50.0%.±.28.9%.. Adding. biosolids. directly.to. the.tailings. produced.less.
native. pasture. coverage. with. further. reduction. apparent. after. the. second.
year..Estimated.cover.on.tailings.treated.with.low.biosolids.was.10.0%.±.2.9%.
in. 2002. and. undetected. in. 2003,. while. the. equivalent. igures. for. tailings.
treated. with. high. biosolids. were. 12.0%. ±. 7.0%. and. 8.3%. ±. 8.3%.. Covers.
formed.of.oxide.alone,.or.oxide.plus.topsoil,.produced.minimal.foliage.cover.
(<2%).in.both.years.
Leaf. material. for. native. grasses. was. harvested. from. most. trialed. cov-
ers.with.the.exception.of.unamended.tailings.or.oxide.treatments..Biomass.
yields. ranked:. oxide. with. high. biosolids. (0.64.±.0.25.kg/m 2 ).>.oxide. waste.
with. low. biosolids. (0.39.±.0.19.kg/m 2 ).>.high. biosolids. (0.13.±.0.06.kg/m 2 ).>.
low. .biosolids. (0.06.±.0.03.kg/m 2 ).>.fertilized. oxide. waste. with. topsoil.
(0.04.±.0.02.kg/m 2 ).>.oxide.waste.with.topsoil.(0.03.±.0.01.kg/m 2 ).=.fertilized.
oxide.waste.(0.03.±.0.01.kg/m 2 )..The.concentration.of.arsenic.in. M. stipoides .