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ISSN 00978078, Water Resources, 2015, Vol. 42, No. 7, pp. 897–908. © Pleiades Publishing, Ltd., 2015.
Original Russian Text © E.G. Egidarev, E.A. Simonov, 2014, published in Geoekologiya. Inzhenernaya Geologiya. Gidrogeologiya. Geokriologiya, 2014, No. 5, pp. 429–441.
897
INTRODUCTION
Rivers in the Amur basin are rich in gold placers,
which have been developed over more than a century
[14]. Since the 1960s, heavy equipment have been in
use in gold mining in the Amur basin, accompanied by
the involvement of technologies that damage river
channels and, thus, river ecosystems. Notwithstanding
the large number of scientific publications on the envi
ronmental impact of gold mining [1, 4, 7, 9, 11, and
many others], an integral estimate of the impact of
goldmining facilities on ecosystems in Amur river
basin is still to be made. The experience of control
organizations shows that, because of the large number
of teams and the remoteness of their operation areas,
it is impossible to implement permanent monitoring
of water quality and watercourse conditions under the
effect of gold mining. The result is that there is no
objective picture of the effect of gold mining on water
courses, and the government fails to see the acute
environmental, economic, and social problems
caused by such activities. The coalition Rivers without
Boundaries (RwB) in cooperation with the Pacific
Institute of Geography, Far East Branch, Russian
Academy of Sciences, supported by the Whitley Fund
for Nature, Global Green Grants Fund, and the Amur
Branch of WWF, analyzed the effects of gold mining in
the Amur basin, which are visible from the space with
the aim to assess the extent and distribution of such
effects and to determine the possible managerial
actions to minimize it. This article gives the results of
the thematic mapping of the effect of gold mining
based on space photographs and the primary analysis
of their distribution and potential impact on river
basins.
METHODS
The scale and spatial distribution of placer gold
mining on the natural complexes were determined
through the interpretation of various space photo
graphs (SPh) made from GeoEye, Spot, Aster, and
Landsat (5 and 7). The study involved more than
1000 SPh scenes, which underlay thematic mapping
of watercourses transformed by gold mining. The
extraction of placer gold by dredging causes radical
changes in river valleys, removes fertile soil layer along
with vegetation and outwashes sands on valley bed.
Such environmental changes are recorded by SPh of
medium and high resolution and next identified and
mapped by interpretation indices. On the site, the
watercourses affected by mining represent anthropo
genic landscape with predominant deposits of out
washed rocks with small dams. On SPh, they can be
seen as a light band along the river, sometimes, with
black spots (Figs. 1, 2). This is a picture most often
seen in the Russian territory, where reclamation oper
ations are not fully implemented. In China, a consid
erable portion of affected watercourses is reclaimed,
and others do not contain chains of dams because
hydraulic monitor operation or dredging gold extrac
tion predominates.
ENVIRONMENTAL POLLUTION
Assessment of the Environmental Effect of Placer Gold Mining
in the Amur River Basin
E. G. Egidarev
a
and E. A. Simonov
b
a
Pacific Institute of Geography, Far East Branch, Russian Academy of Sciences/Amur Branch of the World Wildlife Fund
(WWF–Russia), ul. Radio 7, Vladivostok, 690041 Russia
Email: egidarev@yandex.ru
b
International Coalition Rivers without Boundaries; Dalian, China,
Email: esimonovster@gmail.com
Received December 10, 2012; in final form April 16, 2013
Abstract
—Data of remote sensing of the Earth surface were used to carry out thematic mapping of water
courses affected by gold mining in the Amur R. basin and to evaluate their characteristics. GIStechnology
underlay an attempt to give an overall estimate of the extent and distribution of the impact of goldmining
activities and to determine potential managerial actions to minimize it. The obtained data were used to con
struct a pioneer estimate of the effect of placer gold mining in the Far East region. Input data on gold mining
for different river basins are given.
Keywords
: deposits, gold, placers, geoenvironmental mapping, Amur basin
DOI:
10.1134/S0097807815070039
898
WATER RESOURCES
Vol. 42 No. 7 2015
EGIDAREV, SIMONOV
To evaluate the characteristics of the rivers affected
by gold mining, a model of river network in the Amur
basin should be created, containing the morphometric
data on all watercourses. Watercourses and the bound
aries of drainage basins were identified by using soft
ware module Hydrosheds, developed by the World
Wildlife Fund in cooperation with US Geological Sur
vey and operating with digital elevation models
(DEM) [18]. A reliable DEM was chosen to be based
on data of radar satellites, i.e., the most recent version
of Shuttle Radar Topography Mission (SRTM) [17].
The thalweg network is constructed in ArcGIS envi
ronment with the use of two raster matrices derived
from DEM: flow direction grid and flow accumulation
(net grid). Next, all identified transformations of
watercourses were projected onto a model of river net
work and the shares of watercourses damaged by gold
mining and lying further downstream were calculated.
In Mongolian territory, the identification of placer
mines by SPh in treeless areas was unsatisfactory.
Therefore, public data on current licenses as of 2009
was used, enabling the exact location of 70% of placer
mines and territories of current licenses. Considering
the short prehistory of gold mining in Eastern Mongo
lia, the result of mapping did not differ significantly
from the interpretation of space photographs made for
Russia and PRC.
The data were verified using inquiries among
experts and residents, field surveys of selected gold
mining areas in the three countries, analysis of appro
priate literature and documentation on mining activi
ties and deposits [3, 6, 10]. The study did not reveal old
placer mines not involved in development within the
recent 10–20 years and those overgrown with vegeta
tion, as well as the newest development sites, for which
new SPh were not been found. Theoretically, the over
growing is faster in the southern part of the basin;
therefore, the percentage of identified placer mines in
northern regions was supposed to be higher. However,
the authors have no sufficient factual data to support
Fig. 1.
The valley of the Kirkun R., affected by gold mining, at the mouth of its tributary, the Vereya R. (photo Aster August 4,
2011).
WATER RESOURCES
Vol. 42 No. 7 2015
ASSESSMENT OF THE ENVIRONMENTAL EFFECT 899
this assumption. The percentage of identified old min
ing sites (10 and more years ago) depends on the type
of landscape: in mountain areas, the signs of mining
persist longer than on plains or in swamps, which
faster overgrow with meadow of bog vegetation.
For the analysis of the impact, the Amur basin was
divided into freshwater ecological regions, which, in
turn, were divided into large subbasins [15]. The total
of 15 subbasins was considered. Transboundary basins
were divided into parts belonging to different coun
tries, and the boundary watercourses were analyzed
individually or were excluded from evaluation of sta
tistics for the country. The distribution of damaged
basins of watercourses was calculated for both subba
sins and countries. The major computations were car
ried out in the ArcGIS 9.2 environment.
RESULTS OF THE STUDY
Overall, 1123 sites of damaged river valleys, distin
guishable from the space, were identified in the Amur
Basin, their total area being 2111 km
2
, or 3.4% of the
area of all natural water bodies in the basin (Fig. 3).
The area of all water bodies was evaluated by combin
ing vector topographic layers of the scale of 1 : 500000
and a database on large water bodies SRTM Water
Body Database (SWBD) [21]. This model of the area
of all natural water bodies in the basin during dry (low
water) season was developed in the course of the anal
ysis of the effect of HPP on the Amur Basin [2]. The
transformed territories are comparable with the area of
the Zeiskoe Reservoir, the largest in the basin
(2400 km
2
) or with the total area of all populated
localities in the Russian part of the basin (2131 km
2
,
according to the cartographic data Vmap0) (Table 1).
River valleys are damaged over a total distance of
6537 km, which amounts to 1.6% of the total length of
the river network in the Amur Basin. This is 2000 km
longer than the Amur R. from its source to mouth
(4444 km). The preliminary analysis has shown that
Fig. 2.
River valleys affected by dredging gold mining, Zeya
district, Amur oblast. 2010 (photo Landsat7 ETM).
Table 1.
The areas of the transformed river valleys in the Amur basin
River basin Basin area,
km
2
The number
of affected
watercourses
Percentage
of affected areas
in the basin
The area
of affected
watercourses/
territories, km
2
The area
of water bodies
in the basin, km
2
The percentage
of the area
of affected water
bodies in the basin
Amgun 54752 55 0.19 106 2011 5.3
Argun 294725 121 0.06 180 6655 2.7
Bureya 70393 34 0.07 52 2100 2.5
Lower Amur 213474 89 0.04 85 1144 0.7
Middle Amur 187117 249 0.25 467 3960 11.8
Selemdzha 68714 109 0.49 339 1469 23.1
Shilka 201619 137 0.17 345 3182 10.9
Sungari 554081 89 0.02 100 15748 0.6
Ul'dza 70512 22 0.02 18 1809 1
Ussuri 195669 25 0.01 21 8822 0.2
Zeya 164306 193 0.24 397 5368 7.4
Amur, total 2075 360 1123 0.1 2111 62 573 3.4
Russia 1008 125 763 0.16 1618 33778 4.8
China 882788 322 0.05 448 25851 1.7
Mongolia 184981 38 0.02 44 2943 1.5
900
WATER RESOURCES
Vol. 42 No. 7 2015
EGIDAREV, SIMONOV
the ratio of the length of damaged reaches to all water
courses of the river is a more reliable characteristic
than the ratio of the area of damaged sites to the area
of all water bodies in the basin (Table 2).
The distribution of the intensity of damage in river
valleys over its subbasins is very uneven. The percent
age of damaged areas is maximal in the subbasins of
the rivers Selemdzha, Middle Amur, and Shilka,
where it exceeds 10%; the percentage of the length of
river network most damaged by gold mining is largest
in the Selemdzha, Middle Amur, Zeya, and Amgun,
where this characteristic is in excess of 3%. The least
percentages of damages were recorded in the subbasins
of the Ussuri, Sungari, and Lower Amur (all less than
1%).
The analysis of parts of the subbasins belonging to
different countries shows a radical distinction of the
Russian part of the Argun Basin, where 11% of the
area of water bodies and 3.3% of the length of river
network is damaged. The distribution of damaged
areas of water bodies and the lengths of river networks
over countries is very uneven. The Russia’s share is
1618 km
2
in 763 damaged areas, occupying 4916 km of
river network. This accounts for 4.8% of the length of
natural water bodies and 2.4% of the length of river
network (less the boundary rivers). The same charac
teristics in China and Mongolia are appreciably less
(Table 3).
The mining of placer gold has various effects on
downstream segments of river network both during the
mining and many years after its cessation. The erosion
of damaged segments leads to the downstream trans
portation of large amounts of fine silt and sand parti
cles, affecting both the transparency of water and the
formation of channel ecosystems. The damaged areas
hamper the migration of fish either upstream or down
stream and changes the temperature regime of river
water. The riverine ecosystems downstream of the
mining sites are appreciably polluted by mercury,
which has accumulated over a century of gold mining
and releases during the development of technogenic
placers and erosion of dumps. In this context, one
should take into account the percentage of river net
work subject to the impact of upstream damaged valley
segments. Table 4 gives the percentage of the river net
work length under such effect in each subbasin.
The relative intensity of such impact is more diffi
cult to assess. Different impacts manifest themselves
over different characteristic periods and spread over
different distances downstream the watercourses [12].
50
°
40
°
130
°
120
°
110
°
120
°
130
°
140
°
IRKUTSK
Baikal
Selenga
ULANUDE
Buryatiya
R
SAKHA (Yakutia)
Zeiskoe Reserv.
Chita
Ingoda
Shilka
Zabaikal'skii krai
Amur
Amurskaya oblast
Uda
Maya
Tuve
Onon
Argun
MONGOLIA
Henty
UNDERKHAAN
Kerulen
Dornod
CHOIBALSAN
Inner Mongolia
Nonni
BLAGOVESHCHENSK
Bureiskoe Reserv.
Boundary
State
Regional
Amur Basin
City
Gold mining on rivers visible on SPh
Basins of large rivers
Shilka
Sungari
Ul'dza
Ussuri
Zeya
Drainless basin
Amgun
Argun
Bureya
Lower Amur
Middle Amur
Selemdzha
CHANGCHUN
Jilin
Shenyang
Liaoning
KOREA
CHONGJIN
VLADIVOSTOK
Primorskii krai
Sea of Japan
Edigarev E.G.
Simonov E.A.
km
Zeya
Khabarovsk krai
BIROBIDZHAN
Evreiskaya AO KHABAROVSK
Heilongjiang
Sungari
HARBIN.
Amgun
Ussuri
Onon
USSIA
CHINA
0100 200 400 600 800
©
©
E
W
N
S
Fig. 3.
River segments affected by gold mining and visible from the space.
WATER RESOURCES
Vol. 42 No. 7 2015
ASSESSMENT OF THE ENVIRONMENTAL EFFECT 901
However, in general, we think it reasonable and justi
fied to take the sum of lengths (or areas) of river
reaches damaged by gold mining as a measure of
potential impact on the downstream reaches (Fig. 4).
The summing was implemented by a standard
function “downstream accumulation” with the use of
HydroSHEDS tool. Such estimate better demon
strates the accumulating effect (migration of mercury,
heavy metals, etc.). The same effect can be expressed
by the percentage of the length of damaged upstream
reaches in the length of the river network (Fig. 5),
which better illustrates the potential concentrations of
suspended matter, the watercourse load due to ero
sion, etc.
The expert interpretation of space photographs
reveals only a portion of river valleys damaged by gold
mining. For example, the destroyed areas in
Heilongjiang province were mostly floodplain com
plexes, bogs, meadows, as well as various forest com
munities. In the Bol’shoi and Malyi Khingan, the
mining has led to largescale soil erosion, silting of
downstream watercourses, and heavy pollution of
water. Placer gold mining has seriously affected the
environmental balance in large forest areas of Khin
gan, where the valleys of forest rivers have changed
beyond recognition. The area of dumps on 700 rivers
and creeks in the province amounted to 70–100 thou
sand ha [16]. The interpretation of space photographs
in this area revealed 260 affected watercourses with a
total damaged area of 38 thousand ha. According
to the official Chinese statistics, the damaged area is
2–3 times greater than that identified on the space
photographs in this study. We assume that the percent
age of damaged river valleys identified in our study
accounts for 40–50% of those recorded by Chinese
experts immediately after the cessation of placer gold
mining in Heilongjiang province. The field studies in
August 2011 included the collection of data and anal
ysis of the causes of the failure to identify the areas
affected by gold mining. This is the overgrowth of old
dredging areas by grass and brush, and biological and
agricultural reclamation in some such areas.
An important issue is the rate of recovery of riverine
and valley ecosystems. The opinions of experts regard
Table 2.
The percentage of affected length of river network
River basin The length of affected
watercourses, km
The percentage
of the length
of affected watercourses
in the basin
The length of all watercourses
in the Amur Basin according
to HydroSHEDS 15c, km
Amgun 396 3.5 11404
Argun 644 1.1 60074
Bureya 178 1.3 14044
Lower Amur 348 0.8 43978
Middle Amur 1484 4 37464
Selemdzha 730 5.3 13813
Shilka 975 2.4 41076
Sungari 397 0.4 110644
Ul'dza 60 0.4 13938
Ussuri 109 0.3 37055
Zeya 1250 3.6 34596
Amur, total 6573 1.6 418085
Russia 4916 2.4 202500
China 1514 0.9 174688
Mongolia 138 0.4 37647
Table 3.
Distribution of affected sites over countries in the basin
Country Affected area, km
2
The length of affected
river network, km
The percentage of the area
of natural water bodies
The percentage
of the length of river network
Russia 1618 4916 4.8 2.4
China 448 1514 1.7 0.9
Mongolia 44 138 1.5 0.4
902
WATER RESOURCES
Vol. 42 No. 7 2015
EGIDAREV, SIMONOV
Table 4.
The percentage of the length of affected river network downstream of the affected valleys
River basin (ecoregions)
The length of all watercourses
in the basin according
to HydroSHEDS 15s, km
The length of all affected
watercourses further
downstream, km
The percentage of the length
of affected watercourses
Amgun 11404 2122 19
Argun 60074 4131 7
Bureya 14044 1654 12
Lower Amur 43978 4607 10
Middle Amur 37464 6415 17
Selemdzha 13813 2544 18
Shilka 41071 5824 14
Sungari 110644 4012 4
Ul'dza 13938 717 5
Ussuri 37055 2545 7
Zeya 34596 5322 15
Amur, total 418 080 39894 10
Russia 202500 25868 13
China 174688 7941 5
Mongolia 37647 2843 8
Transboundary rivers 3246 3242 99
ing this point are diametrically opposed, depending on
what state and what components of the environment
are taken as recovered. In addition, geologists often
mention an “increased diversity” of monotype taiga
ecosystems, i.e., the immigration of foreign species
and communities to the sites affected by gold mining.
Overall, the placer gold mining is among the most rad
ical anthropogenic impacts, leading to the destruction
of all components of the local ecosystem. Gold mining
considerably affects the geomorphological structure of
river valleys and, as a rule, completely destroys the fer
tile soil layer that has formed on river banks over
decades and centuries. Thus, even if the return to the
natural state is possible, it will take geological time
intervals, i.e., decades and centuries. In this case, the
recolonization of pebble wastelands by pioneer com
munity and some species of fauna can start only after
the cessation of active mining. In most cases, the eco
systems that form on the mining sites differ signifi
cantly in terms of their relief, the composition of flora
and fauna, as well as geochemical processes, from eco
systems not affected by gold mining. Therefore, this
article does not consider the recovered river valleys
that have not been developed for at least the recent
50 years.
The results of interpretation showed that the mean
percentage of identifying the river valleys damaged by
gold mining in the recent 20–40 years is 40–50% for
PRC and 50–60% for Russia. This difference is due to
the slightly slower overgrowing of the Russian gold
mine areas, which are situated a little further north
ward, and the extremely rare effective biological recul
tivation on them. The actual percent of identification
widely varies over the subbasins because of the differ
ence in the history of activities, the life of the gold
mine, and the processes applied. Extrapolation at least
doubles the previous estimate of the area and length of
disturbed segments, though this can be an underesti
mate, considering the long history of gold mining in
the Russian part of the basin (Table 5).
Thus, the most likely total area damaged by placer
gold mining in the Amur Basin is 4200 km
2
and it
directly affects about 13000 km of river network. This
amounts to about 7% of the area of water bodies and
about 3% of the total length of the rivers. Two thirds of
the length of the damaged rivers and three quarters of
damaged areas lie in Russia. Here the damaged area
accounts for about 10% of the total area of water bod
ies and about 5% of the total length of river network.
For comparison: all large reservoirs in the Amur
Basin occupy less than 8% of the total area of water
bodies in the basin, of which the Russian reservoirs
alone occupy 9% of the area of water bodies in the
Russian part. If we compare this with the impact on
terrestrial ecosystems, the cutting in the last decade of
the XX century affected 1% of forest areas in the
southern Russian Far East [19]. At the turn of the cen
tury, the populated localities and infrastructure occu
pied 0.4% of the Russian territory of the Amur Basin,
while the plough land occupied 4.4% [5]. Compared
with the same part of the basin, the area damaged by
gold mining will account for 0.3%. All this allows us to
conclude that placer gold mining is among the most
WATER RESOURCES
Vol. 42 No. 7 2015
ASSESSMENT OF THE ENVIRONMENTAL EFFECT 903
important transformation impacts on terrestrial and
aquatic ecosystems in the Amur Basin.
In this study, we analyze the impact only on heavily
damaged areas, where soil cover is completely
removed and the transformation involved 85–100% of
50
°
40
°
115
°
125
°
130
°
140
°
135
°
IRKUTSK
Baikal
Selenga
ULANUDE
Buryatiya
R
SAKHA (Yakutia)
Zeiskoe Reserv.
Chita
Ingoda
Shilka
Zabaikal'skii krai
Amur
Amurskaya oblast
Uda
Maya
Tuve
Onon
Argun
MONGOLIA
Henty
UNDERKHAAN
Kerulen
Dornod
CHOIBALSAN
Inner Mongolia
Nonni
BLAGOVESHCHENSK
Bureiskoe Reserv.
Boundary;
State
Regional
Amur Basin
City
Gold mining on rivers visible on SPh
CHANGCHUN
Jilin
Shenyang
Liaoning
KOREA
CHONGJIN
VLADIVOSTOK
Primorskii krai
Sea of Japan
Edigarev E.G.
Simonov E.A.
km
Zeya
Khabarovsk krai
BIROBIDZHAN
Evreiskaya AO KHABAROVSK
Heilongjiang
Sungari
HARBIN.
Amgun
Ussuri
Onon
USSIA
CHINA
0100200
Amur
45
°
120
°
125
°
130
°
135
°
140
°
30050100
E
W
N
S
The length of the affected watercourse (km)
@СухеБатор
@БАРУУНУРГ
@Далайнор
120
°
115
°
110
°
105
°
@Ханка
55
°
50
°
45
°
©
©
1–100
101–450
451–1200
1201–2000
2001–6742
Fig. 4.
Downstream impact. The thickness of the line is proportional to the sum of the lengths of segments affected by gold mining
in upstream river reaches.
Table 5.
Extrapolation of affected areas
River basin
Basin area, km
2
The percentage
of the affected basin area
The area of affected
watercourses/territories, km
2
The area of water bodies i
n the basin, km
2
The percentage of the area
of affected water bodies
in the basin
The length
of the affected
watercourses, km
The length of all watercourses
in the Amur Basin
by the model
of river network, km
The percentage of the length
of affected water bodies
in the basin
Amur, total 2075360 0.2 4221 62573 6.7 4492 418085 3.1
Russia 1008125 0.32 3236 33778 9.6 3052 202 500 4.9
China 882788 0.1 896 25851 3.5 1288 174 688 1.7
Mongolia 184981 0.05 8 2943 3 152 37647 0.7
904
WATER RESOURCES
Vol. 42 No. 7 2015
EGIDAREV, SIMONOV
the area, not taking into account the much larger areas
of terrestrial ecosystems transformed partially or suf
fering an indirect effect of mining. The studies of S.D.
Shlotgauer [13] show that the area of landscapes sub
ject to partial transformation and indirect effects can
be 50 times greater than the size of heavily transformed
areas [13].
Gold mining shows different environmental effect
in different countries. For example, in China, agricul
ture, municipal infrastructure, and industrial pollu
tion have larger effect on the local aquatic ecosystems
than gold mines. In Mongolia, gold mining is much
more widespread in the boundary basins, such as that
of the Selenga R., while the Amur Basin contains as
little as 30–50 license areas, half of which are aban
doned. In Russia, gold mining has most considerable
effect on aquatic ecosystems in the majority of subba
sins, and it is only in 3 subbasins, that its impact is not
dangerous.
The extent of gold mining in many subbasins can be
compared with the use of an index of overall distur
bance, evaluated as the sum of the percentage of the
lengths of damaged watercourses plus the percentage
of the river network affected by gold mining further
downstream. This index has a direct physical meaning:
these are all river network segments subject to the
impact of gold mining (Table 6).
RESULTS AND DISCUSSION
The effect of gold mining is unevenly distributed
over fragments of river network and, accordingly, dif
ferent types of riverine ecosystems. To illustrate this,
let us divide the watercourses into 3 dimensional
classes (the source, the upper reaches, the lower and
middle reaches) and consider the disturbances
observed in those classes within elevation ranges of
below and above 500 m above sea level. These two
characteristics remain significant for distinguishing
between the types of ecosystems as they reflect the dif
ference between temperature regimes, the position in
the river network, the dimensions of the watercourse,
runoff volumes, etc. There are good reasons to sup
pose that, within the same ecoregion, watercourses
with different orders and elevation above sea level dif
50
°
40
°
130
°
120
°
105
°
130
°
135
°
140
°
IRKUTSK
Baikal
Selenga
ULANUDE
Buryatiya
R
SAKHA (Yakutia)
Zeiskoe Reserv.
Chita
Ingoda
Shilka
Zabaikal'skii krai
Amur
Amurskaya oblast
Uda
Maya
Tuve
Onon
Argun
MONGOLIA
Henty
UNDERKHAAN
Kerulen
Dornod
CHOIBALSAN
Inner Mongolia
Nonni
BLAGOVESHCHENSK
Bureiskoe Reserv.
Boundary;
State
Regional
Amur Basin
City
CHANGCHUN
Jilin
Shenyang
Liaoning
KOREA
CHONGJIN
VLADIVOSTOK
Primorskii krai
Sea of Japan
Edigarev E.G.
Simonov E.A.
km
Zeya
Khabarovsk krai
BIROBIDZHAN
Evreiskaya AO KHABAROVSK
Heilongjiang
Sungari
HARBIN
Amgun
Ussuri
Onon
USSIA
CHINA
0100200
Amur
@СухеБатор
@БАРУУНУРГ
@Далайнор
@Ханка
300100 50
©
©
45
°
50
°
55
°
110
°
115
°
120
°
125
°
115
°
125
°
135
°
140
°
45
°
E
W
N
S
0–1
1–2
2–3
4–5
6–10
11–100
The percentage of the length of river network
affected by gold mining in upstream river
segments
Fig. 5.
Downstream impact. The thickness of river lines is proportional to the percentage of the length of the river network affected
by gold mining in upstream river segments.
WATER RESOURCES
Vol. 42 No. 7 2015
ASSESSMENT OF THE ENVIRONMENTAL EFFECT 905
fer in their role in the river ecosystem and often serve
as habitats for different communities and species.
The study considers the principles of the order
based classification of river systems as a method for
measuring river network by the orders of watercourses,
including the distribution of the measured water
courses in the river network by Strahler system [20].
The Strahler’s orders suggest the much higher distur
bance of the watercourses of the first three orders, as
can also be seen from the obtained data (the analysis
embraced only the Russian territory, Table 7).
Overall, the disturbance by 80% can be seen more
frequently in watercourses with elevations more than
500 m above sea level; among those, space photo
graphs show 3.3% of damaged segments in the total
length. In the Middle Amur and Selemdzha, the dis
turbances in such watercourse reach 10% of their
length. In the Argun basin, the percentage of damaged
watercourses above 500 m is almost 5 times as large as
that for rivers below 500 m.
However, the Shilka Basin shows a radically differ
ent trend: the disturbance in the watercourses less than
Table 6.
Characteristic of the overall disturbance of river ecosystems
River basin
The length of all
watercourses in
the basin by
river network
model, km
The percentage
of the length
of affected
downstream
watercourses*
The percentage
of the length
of affected
watercourses
in the basin
Extrapolation,
percent
of the length
of affected
watercourses
in the basin
Total percent
age of affected
objects, %
Total percentage
of affected
objects
with extrapola
tion taken
into account, %
Amgun 11 403.9 18.6 3.5 7 22.1 25.6
Argun 60 073.7 6.9 1.1 2.1 7.9 9
Bureya 14044 11.8 1.3 2.5 13 14.3
Lower Amur 43978.4 10.5 0.8 1.6 11.3 12.1
Middle Amur 37464 17.1 4 7.9 21.1 25
Selemdzha 13812.8 18.4 5.3 10.6 23.7 29
Shilka 41070.9 14.2 2.4 4.7 16.6 18.9
Sungari 110 643.6 3.6 0.4 0.7 4 4.3
Ul'dza 13 937.6 5.1 0.4 0.9 5.6 6
Ussuri 37 055.4 6.9 0.3 0.6 7.2 7.5
Zeya 34596 15 3.6 7.2 19 22.6
Amur, total 418080 10 1.6 3.1 11 12.7
Russia 202500 13 2.4 4.9 15 17.6
China 174 688 5 0.9 1.7 5 6.3
Mongolia 37647 8 0.4 0.7 8 8.3
* The extrapolation method cannot be used to improve the estimates of the lengths of watercourses affected downstream, so data given
in Table 4 were used.
Table 7.
Difference in the disturbance and the order of a watercourse (Strahler) in the Russian part of the basin
Order of the watercourse
(Strahler)
The length
of all watercourses, km
The length
of affected watercourses, km
The percentage of affected
watercourses of this order
1 104 821.7 2632.4 2.5
2 49800.8 1371.6 2.8
3 23169.9 646.6 2.8
4 13082.9 164.2 1.3
5 6716 88.7 1.3
6 3254.9 12.5 0.4
7716.400
8937.200
Total 202 499.8 4916 2.4
906
WATER RESOURCES
Vol. 42 No. 7 2015
EGIDAREV, SIMONOV
500 m above sea level is almost twice as large, reaching
almost 5% of the total length of the watercourses.
Of greatest interest is the result of consideration of
six conditional types of riverine ecosystems classified
by a combination of elevation above sea level and
aggregate orders (Table 8). The maximal impact for
watercourses less than 500 m above sea level was
revealed for 1storder watercources in the Amgun
Basin (4.54%) and 2nd–3rdorder water bodies in the
Shilka basin (11.6%). The largest effect in water
courses higher than 500 m above sea level was revealed
for 1storder water bodies in the basins of the Middle
Amur (9.1%) and the Selemdzha (8.5%), 2nd–3rd
order watercourses in the basins of the Zeya (5.27%),
Amgun (6.26%), Middle Amur (11.6%), Selemdzha
(12.9%), and the 4th and higher orders in the Selem
dzha (7.81) and the Middle Amur (15.8%).
It should be remembered that the use of SPh can
not ensure the identification of all disturbances. As to
the Amur basin, the damaged area is supposed to be
about half as large again as that identified in this study.
Thus, the effect of gold mining is very different in dif
ferent types of riverine ecosystems, which, in some
cases, may lead to a considerable decrease in the areas
of individual types and, accordingly, the area of species
inhabiting them.
The damages of individual habitats caused by gold
mining require detail analysis. For example, Guo
Yumin showed that the damage to wetland valleys,
habitats of the hooded crane (
Grus monacha
) is dispro
portionally large in the Chinese part of the Malyi
Hinggan. It is very likely that the same tendency is typ
ical of the Russian part of its area. The relatively wide
and gentle midland river valleys with beds covered by
alluvial deposits and sedge moors with larches, are the
favorite nestling area of this crane and, at the same
time, the very likely area of primary accumulation of
goldbearing material. Water brings it from the nearby
steep mountains and leaves it in the nearest river seg
ments with conditions favorable for the accumulation
of alluvium. To verify this hypothesis requires a wide
inquiry among the personnel of goldmining teams.
In some subbasins (Shilka, Argun, Selemdzha,
Middle Amur, and Amgun) the primary issue is the
effect of gold mining on the reproduction areas of fish
of salmon family: chum salmon, taimen, lenok, and
Table 8.
The disturbance of different ecological types of watercourses (only for Russian territory)
Elevation Subbasin
The percentage of affected watercourses
the percentage
of the lengths of affected
watercourses (all)
1st order 2nd–3rd orders higher than the 3rd order
All watercourses
below 500 m
Amgun 3.43 4.54 3.11 1.06
Argun 0.74 0 2.6 0.22
Bureya 0.9 1.4 0.81 0
Lower Amur 0.86 1.35 0.51 0
Middle Amur 2.01 2.17 2.07 1.5
Selemdzha 3.52 2.99 4.79 2.26
Shilka 4.86 4.43 11.16 0.88
Ul'dza 0 0 0 0
Ussuri 0.37 0.83 0.13 0.06
Zeya 3.26 3.7 3.87 0.77
Total 1.82 2.17 1.96 0.63
All watercourses
above 500 m
Amgun 3.6 2.27 6.26 0.51
Argun 3.44 3.21 3.99 3.17
Bureya 1.71 1.54 2.22 0
Lower Amur 0.27 0.21 0.42 0
Middle Amur 10.46 9.07 11.57 15.83
Selemdzha 9.94 8.54 12.85 7.81
Shilka 2.6 2.46 3.29 0.97
Ul'dza 0.4 0.66 0 0
Ussuri 0.27 0.31 0.22 0
Zeya 4.42 4.16 5.27 0.67
Total 3.29 2.95 4.12 2.16
WATER RESOURCES
Vol. 42 No. 7 2015
ASSESSMENT OF THE ENVIRONMENTAL EFFECT 907
grayling. It is likely that a considerable portion of best
habitats will be lost and the access to other habitats will
be hampered by higher water turbidity downstream of
those areas.
CONCLUSIONS
This work has been intended to become a starting
point for the future studies and analysis of the environ
mental effect of placer gold mining. Later, it is reason
able to carry out a parallel analysis of the direct and
indirect effects of gold mining on both terrestrial and
aquatic ecosystems. The integral analysis of the impact
of mining on riverine ecosystems should be based on a
basin approach and modern GIStechnologies, which
enable the processing of large bodies of space data.
Placer gold mining is the most widespread source
of considerable adverse effects on water bodies in the
Amur Basin comparable with the effects of HPPs and
municipal infrastructures.
The likely total area affected by placer gold mining
in the Amur Basin is 4200 km
2
, corresponding to about
13000 km of river network. This accounts for about 7%
of the area of water bodies and about 3% of the total
length of watercourses. Two thirds of the affected river
length and three quarters of the affected areas are con
centrated in Russia. Here, the affected area accounts
for about 10% of the total area of water bodies
and about 5% of the total length of river network, i.e.,
2–4 times larger than that in PRC or Mongolia.
Importantly, the mining of placer gold in the boundary
areas of PRC was ceased as contradicting to the policy
of sustainable development of forest regions. A law was
passed in Mongolia, which radically restricts mining
in water protection zones and near river sources. How
ever, in Russia the legislative and executive bodies take
no measures at all to create conditions for preservation
of ecosystems, which may include
⎯
the governmental and public control of nature
use;
⎯
expert estimations (strategic analysis of the list of
deposits) of the advantages and drawbacks and rejec
tion of unfavorable sites, where the drawbacks are
likely to be in excess of the advantages;
⎯
the use of new, environmentally benign technol
ogies in gold mining;
⎯
partial or complete restriction of gold mining in
new areas and inclusion of such deposits in the federal
fund of subsurface reserves (a fund for future genera
tions), as far as the current technologies and organiza
tional conditions fail to enable their development
avoiding considerable damage [8].
The effect of placer gold mining on local areas of
river valleys consists in the complete destruction of the
biotic component of biocenoses and the geomorpho
logical transformation of channels, beds, and valley
slopes. The effect on river network parts downstream
of mining sites is multiplefactor and, obviously, can
accumulate downstream the river. The largest hazard
of this type of nature use is the propagation of the
impact over the river network, which can reduce the
habitats of species and communities and cause mass
pollution of streams (including hightoxicity mercury
pollution) and their partial degradation.
Accordingly, the most effective measures for the
prevention of damage imply the territorial limitations:
a ban to extend the mining to new segments of river
network and most vulnerable and valuable natural
complexes and socially significant parts of river basins.
REFERENCES
1. Bubnova, M.B., A method for integral assessment of
environmental pollution at the development of deposits
of nonferrous and rare metals,
Gorn. Zhurn.
, 2006,
no. 4, pp. 86–91.
2. Egidarev, E.G., Geoinformation simulation of geoen
vironmental situations in the Amur R. basin at HPP
construction,
Ispol’zovanie GIS i DDZZ pri reshenii
prostranstvennykh zadach: sb. nauch. tr
(The Use of GIS
and RS in Solving Spatial Problems: Collection of Sci
entific Papers), Perm: OOO “Uchebnyi tsentr “Infor
matika”, 2011.
3. Zhelnin, S.G., A method for reconstructing the basic
gold sources—a basis for identifying the general regu
larities in their distribution, local forecasting, and
exploration, in
Geologiya i ekologiya basseina reki Amur.
III sovetskokitaiskii simp.
(Geology and Ecology of the
Amur R. Basin. III Soviet–Chinese Symp.), Blagovesh
chensk: “Amurskaya pravda”, 1989, vol. 1, pp. 28–30.
4. Zelinskaya, E.V., Environmental impact of placer min
ing,
Gorn. Zhurn.
, 1998, no. 5, pp. 27–28.
5. Karakin, V.P., Land resources of Amur R. basin,
Vestn .
DO RAN
, 2004, no. 4, pp. 23–37.
6. Moiseenko, V.G. and Eirish, L.V.,
Zolotorudnye mestor
ozhdeniya Vostoka Rossii
(Gold Deposits in Eastern
Russia), Vladivostok: Dal’nauka, 1996.
7. Pashkevich, M.A.,
Tekhnogennye massivy i ikh vozde
istviya na okruzhayushchuyu sredu
(Technogenic Mas
sifs and Their Environmental Effect), St. Petersburg:
St.Pb. Gorn. Inst., 2000.
8. RF Governmental Decree of July 1, 2013, no. 552, “On
the formation of a federal fund of subsurface reserve
areas,” Official Webportal of legal information, Gov
ernmental System of Legal Information.
http://pravo.gov.ru:8080/page.aspx?52527
9. Saksin, B.G., Prediction environmental estimate of the
regional environmental impact of activities for mining
nonferrous and rare metals in Eastern Russia,
Tikhookean. Geol.
, 2008, vol. 27, no. 5, pp. 115–123.
10. Sorokin, A.P., VanVanE, A.P., et al.,
Atlas osnovnykh
zolotorossypnykh mestorozhdenii yuga Dal’nego Vostoka i
ikh gornogeologicheskie modeli
(Atlas of Major Gold
Placers in the Southern Far East and their Mining and
Geological Models), Vladivostok: DVO RAS, 2000.
11. Trubetskoi, K.N., Galchenko, Yu.P., and Burtsev, L.I.,
Ekologicheskie problemy osvoeniya nedr pri ustoichivom
razvitii prirody i obshchestva
(Environmental Problems
in the Development of Mineral Resources under Sus
1
1
908
WATER RESOURCES
Vol. 42 No. 7 2015
EGIDAREV, SIMONOV
tainable Development of the Nature and Society),
Moscow: Nauchtekhlitizdat, 2003.
12. Shvedov, D.S., Evolution of river valley geosystems,
disturbed by placer mining, in
Mater. XIV sov. Sibiri i
Dal’nego Vostoka
(Mater. XIV Meeting of Siberia and
Far East), Vladivostok: Dal’nauka, 2011, pp. 440–443.
13. Shlotgauer, S.D.,
Antropogennaya transformatsiya rasti
tel’nogo pokrova taigi
(Anthropogenic Transformation
of Taiga Vegetation Cover), Moscow: Nauka, 2007.
14. Eirish, L.V., Some geological and geomorphological
features of gold placer formation in the Amur Region,
Tikhookean. Geol.
, 2008, vol. 27, no. 5, pp. 104–114.
15. Abell, R.A., Thieme, M.L., et al., Freshwater ecore
gions of the world: a new map of biogeographic units for
freshwater biodiversity conservation,
BioScience,
May,
2008, vol. 58, no. 5, pp. 403–414.
16. Heilongjiang Mining Plan (2008–2015). 2007.
17. Jarvis, A., Reuter, H.I., Nelson, A., and Guevara, E.,
Holefilled SRTM for the globe Version 4, available
from the CGIARCSI SRTM 90m, 2008. Database:
http://srtm.csi.cgiar.org.
18. Lehner, B., Verdin, K., and Jarvis, A., HydroSHEDS
Technical Documentation. World Wildlife Fund US,
Washington, DC, 2006. Available at http://
hydrosheds.cr.usgs.gov.
19. Sheingauz, A.,
Overview of the Forest Sector in the Rus
sian Far East: Production, Industry, and Illegal Logging:
Asia Pacific Partners Working Paper,
no. 2, Forest
Trends, Washington, D.C., U.S.A. 2004.
20. Strahler, A.N., Quantitative analysis of watershed geo
morphology,
Trans. Am. Geophys. Union
, 1957, vol. 8,
no. (6), pp. 913–920.
21. USGS. Shuttle Radar Topography Mission Water Body
Dataset, 2006. Available online at http://dds.cr.usgs.gov/
srtm/version2_1/SWBD/ (accessed 01/08/2006).
Translated by G. Krichevets
SPELL: 1. OK
