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Human impacts in catchments and lakes of the Antarctic oases Schirmacher , Thala and Larsemann Enn Kaup Institute of Geology at Tallinn University of Technology, Estonia Review of research during 1976-1998 at Novolazarevskaya, Molodezhnaya, Progress, Zhong Shan, Law Base

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Human impacts in catchments and lakes of the Antarctic oases

Schirmacher , Thala and Larsemann

Enn Kaup Institute of Geology at Tallinn University of

Technology, Estonia

Review of research during 1976-1998at Novolazarevskaya, Molodezhnaya,

Progress, Zhong Shan, Law Base

Bunger Hills, March 1989: a view to SW from the Oasis-2 Station over Lakes Algae and Dolgoje

Transfer of human impacts to antarctic lakes and their catchments

● Long-range pollutant transfer by global oceanic and atmospheric circulation. Decrease of ozone layer.

● Local impacts through construction and running scientific stations and field camps

● Connected recreation activity of stations' staff and recreation activity of visiting tourists

● Direct research activity of scientists, limnologists included

Direct impacts of scientific stations

● Modification (leveling, crushing, using as building material) of surface by construction of facilities and road networks and operating transport. Including the use of tracked, wheeled vehicles and trampling by pedestrians. Damaging of catchment vegetation has been common.

● This can change hydrological patterns (direction of flow, quantity and quality of flowing waters). An example is increasing of fine sediment (e.g.silt) in the flowing water as a result of rock crushing.

Direct impacts of scientific stations

● Spilling of various construction and exploitation materials and wastes onto the catchments and directly into the lakes. Examples are:

● Cement, metal and wood particles, paints, fuels, lubricants & other liquids

● Solid and liquid domestic wastes● Emissions of various engines (power stations,

vehicles) and waste incinerators

Novolazarevskaya Station in the E part of Schirmacher Oasis, 1961-84

Lake Stancionnoye: water pipe with power plant, sauna-laundry and kitchen as sources of

pollution

Diesel oil discharges were not unusual; one was told to have been 10 tons

A tracked vehicle was driven into L. Stancionnoye without a reason and had to

be rescued by another one

During 1961-76 were station's wastes (food, faeces, oils, H

2-production tails, etc.) stored

on the ice cover of Lake Glubokoye

Loads of nutrients (mmol m-3 of lake) into the lakes during summer flow periods of 1976/77 and

1983/84. Pt - total phosphorus, DRP - dissolved

reactive phosporus, Ninorg

- inorganic nitrogen.

Lake, period Pt DRP Ninorg

Glubokoye 76-77 - 0.740 7.130Glubokoye 83/84 0.074 0.027 1.322Pomornik 83/84 0.530 0.110 4.703Verkhneye 83/84 0.010 0.006 0.348

In 14 years mixing of most of water column was replaced by anaerobic mesothermy

Depth(m)Date

15 May 62 30 Jan 62 28 Aug 76 19 Jan 77

temp temp temp/O2 temp/O2

0.5 2.5 2.6 0.3 / 22.4 2.0 / 13.63 0.4 3.7 1.2 / 17.1 2.1 / 13.75 1.3 4.4 3.2 / 15.1 2.7 / 14.110 4.0 4.2 4.0 / 14.6 3.9 / 14.515 4.0 4.2 3.9 / 14.4 3.9 / 14.520 3.9 4.2 4.0 / 12.8 4.0 / 14.325 4.0 4.2 3.9 / 1.8 4.2 / 2.730 4.2 4.3 3.5 / 0.0 3.6 / 0.032 3.3 / 0.0 3.2 / 0.035 3.0 / 0.0 3.1 / 0.0

Data of Simonov & Fedotov (1964) shows mixing of water column during 1962

Isotherms in Lake Glubokoye during March 1976 – Jan 1977: a case for

anthropogenic meromixis

Dissolved oxygen (mg/l) in Lake Glubokoye during March 1976 – Jan 1977

Dissolved reactive phosphorus (μg P/l)in Lake Glubokye during March 1976 – Jan 1977

Chlorophyll a and primary production of phytoplankton in human impacted and natural

lakes

Lake, period Chl a, mgm-3 PP, mgCm-3d-1

Glubokoye 76-77

0.1-2.10.5

0.1-26.12.8

Stancionnoye76-77

- 2.7-81.528.2

Verkhneye 76-77

<0.05-0.40.07

0.1-2.00.6

Pomornik 76-77

0.1-0.90.3

0.1-2.50.8

Molodezhnaya St. in Thala Hills (ca 10 km2 but many lakes)

Station operated 1962-98, in 70-80s wintering staff 100-150, in summers a few

hundred people

Lakes had stronger impact in 60s, later sewage and wastes were removed into sea

● In 1967-68 the 2 impacted lakes revealed (MacNamara 1970):

● P-PO4 65-460 µg P/l

● N-NH4 620-1320 µg N/l

● Phytoplankton PP 140-370 mgC m-3day-1

● In 1988-89: ● These characteristics were at 1-2 orders of

magnitude lower levels

In 1988 this recreation activity had only a minor and transitory impact on a lake from

where drinking water was pumped

Larsemann Hills were almost pristine until 1986 when...

...ANARE started with summer-only Law Base,

In 1986 SAE started Progress I (1992 abandoned) and 1989 started Progress II

Since 1988 CHINARE operates continuously Zhong Shan

4 stations & road network on ca 5 km2 with many lakes have various impacts

● Change of meltwater flow patterns by road paving resulting:

● Water inflow volumes into lakes changed● Salinity of lake water changed

● Rock crushing by vehicles:● Increased inflow of silt with meltwater and -

decrease of transparency in lake waters● Increased leaching of solutes from crushed rock -

- salinity increase in surface & lake waters

The road far side of small lake: chanelling water flow, rock crushing, increased inflow of water and solutes into lakes

Redirected inreased inflow has progressively desalienated Heart Lake

where sediments pre-dating the LGM were cored (Hodgson et al. 2001)

Monitoring meltwater flows on surface and subsurface (piezometers in active

layer) showed that:● Max levels of DIN and DRP were much

higher in impacted than natural catchments: e.g. 2000 vs 315 µgN/l in subsurface flows; 46 vs 29 µgP/l in surface flows or 108 vs 3 µgN/l of N-NO

2in surface flows

● Max conductivity levels steeply higher in impacted than natural catchments: 4400 vs 380 µS/cm in subsurface flows 2280 vs 230 µS/cm in surface flows

Increased nutrient and conductivity levels were found at all stations in the LH:

Progress I and II, Zhong Shan, Law Base● Their origins had been:

waste (grey) water and urine, chemicals, building materials – direct inputs from stations; rock crushing by tracked vehicles and subsequent increased weathering, showed by silt increases

● Activities causing these changes: happened before Madrid Protocol came into force on 17 January 1998; unlikely that they changed radically after the date

Meltwater flowing on surface and subsurface on slope ZhongShan-No

Worries Lake much enriched with salts and nutrients

2 J

an

11

Jan

13

Jan

17

Jan

24

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31

Jan

0200400600800

1000

Co

nd

uct

ivit

y (

µS

/cm

)

-25-20-15-10-5

0

a Lake No Worries, station inflow2

Jan

19 J

an

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an

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an

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duct

ivit

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µS

/cm

)

b Lake No Worries, piezometers

2 J

an

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Jan

0

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0

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a Station inflow

6 J

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4 F

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b Piezometers

N-NH4

N-NO2

N-NO3

DRP

N-NH4

N-NO2

N-NO3

N-N

H4, N

-NO

3 (g

l-1)

N-N

H4, N

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3 (g

l-1)

N-N

O2, D

RP

(g

l-1)

N-N

O2, D

RP

(g

l-1)

DRP

No Worries Lake at Zhong Shan the most impacted lake at LH: inflow of silt, salts, nutrients, thermal pollution

Consequenses of human impact in No Worries Lake

● Sharp decrease in transparency with silt inflow● Warming lake water, prolonged ice-free period● Temperature increase with depth changed to

temperature decrease with depth● Water salinity increase● Increased inflow of organics, nutrients and

warming have promoted heterotrophic microbial activity (Ellis-Evans et al. 1997)

An example of deep, even profound but still very limited impact of scientific

activity in a lake catchment...

...and tourists invading LH in big numbers (over 100 on a day). Their impact on lakes

was limited to footprints on lakeside...

...leaving the most of their Antarctic impact diluted into the Southern Ocean.