10 Moscow, Ecology, Plants and habitats of European cities
[ Pobierz całość w formacie PDF ]
Moscow
Alexander Shvetsov
Fig. 1
The Kremlin
Abstract
The city, as part of the cultural landscape, is a mobile and highly dynamic
system, the changes of which are related to a variety of economic and social factors.
Periods of stabilisation alternate with periods of fast changes and development of
the city. Vegetative cover as an element of urban environment is directly or indirectly
affected by all these factors and phenomena. Species of natural communities are of
special concern. The reduction in the population size and frequency of many native
species can adversely affect their survival. It is possible that many rare species will
Alexander Shvetsov (
*
)
Main Botanical Garden Russian Academy of Sciences, Botanicheskaya St.,
4, 127276 Moscow, Russia
e-mail: floramoscow@mail.ru
J.G. Kelcey and N. Müller (eds.),
Plants and Habitats of European Cities
,
DOI 10.1007/978-0-387-89684-7_10, © Springer Science+Business Media, LLC 2011
321
322
A. Shvetsov
disappear from the city, primarily those of wet and dry meadows, forest edges,
meadows and marsh communities. There is also another danger, which is generally
overlooked – the loss of native genotypes and their replacement by alien genotypes
of the same taxon. These negative processes can also affect non-native species,
for example, plants of old parks and “relics of cultivation” such as
Chenopodium
bonus-henricus, Luzula luzuloides, Phyteuma spicatum
and
Poa chaixii
.
Natural Environment of the City
Moscow is located at 55°45′ north and 37°37′ east, in the centre of the Russian
Plain and in the watershed of the rivers Volga and Oka. Moscow, the capital of the
Russian Federation, is the largest city of the country and the most northern of the
largest cities in the world. In 1996, it occupied 994 km
2
of which 878 km
2
are
within the boundaries of the Moscow ring road (MKAD), which is 109 km long.
Within the ring road, the city has an oval shape; 42 km north/south and 35 km west/
east. With the new area around the MKAD, these figures are likely to increase to
38 and 52 km, respectively (see Fig.
2
). In 1995, the population was 8.8 million
(Moscow: Encyclopedia
1997
). In the central part of the city, the developed surface
is 7,128 m
−2
h a
−1
, which is reduced to 4,460 m
−2
h a
−1
in the peripheral areas.
By 1997, the average numbers of floors per apartment block was five.
Fig. 2
The territory of Moscow
Moscow
323
Geology
The territory of Moscow is located in the Russian Platform and is founded on
crystalline schists formed by orogenesis during the Archaean and Proterozoic
times. The formation is overlain by 1,650 m of the Riphean, Vendian, Cambrian,
Devonian, Carboniferous, Jurassic, Cretaceous and Quaternary sedimentary rocks.
The Carboniferous deposits are extensive and comprises mainly limestone
up to 350 m deep. Prior to the construction of the Moskva – Volga channel, Coal
Measures outcropped in the river bank above the city centre; at present it is below the
level of the river. The Carboniferous deposits are overlain by Jurassic sands and clays up
to 80 m thick, which in turn are covered by 75 m of Cretaceous sands and clays.
Outcrops of Jurassic and Cretaceous deposits occur in the valley of the Moskva
River and some of its tributaries above and below the city centre.
Virtually, all of the surface geology of the city comprises glacial deposits
40–60 m thick resulting from three glacial periods of the early to mid-Pleistocene.
The deposits include moraines, fluvio-glacial sandy sub-moraines and lacustrine-
glacial formations. Alluvial deposits are represented by sand and clay. Hundreds
of years of human activities have resulted in the formation of technogenic
deposits (cultural layer) (0.5) 4–6 (20) m deep which occupy about 70% of the
city’s territory, including the whole of the city centre. The thickest deposits are
characteristic of landfill sites of old quarries, river valleys, ravines and swamps.
In some areas of the city, a modern technogenic sediment deposit is growing at
an estimated 10 cm/year.
Changes in hydro-geological conditions resulted in a rise in the level of the
groundwater, which is most widespread in the northern and eastern parts of the city,
where a high watertable occupies 40% of the territory and relates mostly to the
watershed spaces of moraine and fluvio-glacial plains.
Topography
The relief of Moscow is formed by Quaternary glaciations and by river erosion
(see Fig.
4
).
The variation in the topography of the city is due primarily to its location at the
crossroads of three large geomorphological regions. The northern part of the city is
located in the Smolensk-Moscow Upland, which comprises a Middle Quaternary
plain 165–185 m a.s.l. with a fluvio-glacial at a lower level (155–175 m a.s.l).
The southern part of the city is occupied by the Moskvoretsko-Oksky erosion
plain which has a maximum height of 255 m a.s.l. and is 130–140 m above the river
bank. The area is characterised by extensive dissections that form ravines and
small river valleys. The Mescherskaya lake-glacial lowland in the eastern part of the
city is a Middle Quaternary outwash plain with a maximum height of 140–160 m a.s.l.
The outwash plain is characterised by a hollow and undissected relief with rare
moraine butte; almost half of the area (43%) has no run-off.
324
A. Shvetsov
The valley complex of the Moskva river and its major tributaries (Yauza, Setun and
Skhodnya) occupies a third of the total area of the city which is divided into four levels:
the flood plain and three terraces. The greatest area is occupied by the third terrace,
which is 30–35 m above river level and occurs throughout the city. The floodplain of
the Moskva river no longer exists – it was flooded when the canal was built.
Human impact on the terrain started with the first settlement and the emergence
of agriculture and the formation of burial mounds. Some of these “micro-changes”
in the topography still occur in the city. As a result of human economic activity the
natural terrain changed simultaneously in two directions, first lowering, such as
levelling elevations and second, elevations such as the accumulation of the cultural
layer. As a result of these processes, the relief of the city was levelling out more and
more resulting in the loss of the natural micro-relief. The intensity of human activity
and its effect on the natural terrain has continued to increase over the millennia.
In the process of development of the territory a large number of small rivers,
ravines, swamps and ponds have been culverted; especially significant are the
landfill areas, which are 3–8 m deep. A large number of elevations were created
during the construction of highways and railroads, some of the latter reaching
13–15 m. In some cases the relief was lowered to reduce the vertical alignment of
transport routes, for example, some of the railway cuttings are 12–17 m deep and
200 m long. In the central and long inhabited parts of the city the terrain has
changed to a greater extent than in the suburbs. Nevertheless even in the dense and
older parts of the city the relief of the former natural terrain is easily visible.
Climate
Moscow is located in a zone of moderate continental climate, whose character is
significantly stronger relative to other major European cities. The largest annual
amplitude in temperature is 28°C. The dominant air mass is air of moderate lati-
tudes, generally coming from the Atlantic Ocean with the Arctic air from the north
and north-east and tropical air from southern Europe also occurring during the year.
The average monthly temperature and rainfall data are given in Table
1
.
The average annual temperature between 1901 and 2000 was 4.53°C. However,
further analysis shows a gradual warming, the data for 1961 to 1990 and 1991 to 2000
show an average annual temperature of 5.02 and 5.75°C, respectively (Isaev et al. 2002).
There are 141 frost-free days, the frosts generally start about 29 September and end
about 10 May, with severe frosts occurring between 24 November and 10 March.
“Permanent” snow cover occurs around 26 November and finally melts about
11 April – by the end of the winter the depth of the snow is (on average) 30–35 cm.
The length of the growing season (number of days with an average daily
temperature of ≥5°С) is 175 days (from 18 April to 11 October). The average tem-
perature in July is about 18.1°C. During the incursions of the cold air from the
Arctic in June, the temperature might drop to −2 to −4°C. Long-term observations,
which started in 1880, show that there has been a gradual warming in the northern
Table 1
The average monthly temperature and rainfall
Average
annual
Month
I
II
III
IV
V
VI
VII
VIII
IX
X
XI
XII
Temperature (°C)
1901–2000
−9.3
−8.6
−3.4
5.1
12.4
16.7
18.4
16.6
10.9
4.4
−2
−6.8
4.53
1961−1990
−9.4
−7.7
−2.2
5.8
13.3
16.8
18.4
16.7
11.1
4.9
−1.4
−6.2
5.02
1991−2000
−5.9
−5.9
−1
7.3
12.7
17.7
18.8
16.8
11.1
5.6
−2.5
−5.5
5.75
Precipitation (mm)
1901−2000
40
34
36
41
52
75
85
78
61
58
50
47
658
1961−1990
43
36
35
44
50
77
91
78
62
57
56
55
684
1991−2000
56
42
41
35
43
90
73
80
65
74
53
51
702
[ Pobierz całość w formacie PDF ]