The publication of this Handbook was supported by the Russian Federation


Impacts and risks of  soil salinity



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Impacts and risks of  soil salinity
The  productivity  of   agricultural  lands  in  arid  and  semi-arid  environments  is  affected  by  the 
accumulation of  salts and the loss of  soil organic matter (SOM). The latter leads to the loss of  
soil fertility and deterioration of  its agrophysical, biological and other properties. Salinization 
processes have a serious impact on soil functions such as its ability to act as a buffer and filter 
against pollutants, its participation in the water and nitrogen cycles and its ecosystem services in 
supporting the health of  the environment and biodiversity.
Soil salinization impacts on the agricultural productivity by causing disruptions to the processes of  
nitrogen uptake and plant growth development. The loss of  biological activity of  soils is associated 
with  the  decline  of   food  supplies  for  soil  microflora  necessary  for  ecosystem  functioning.  The 
abandonment of  arable soils is associated with high risks for soil and environment health and 
significant ecological stress. An increase in soil salinity further deteriorates soil ecosystem services 
and decreases revenues for farmers and smallholders. The loss of  natural vegetation and forests is 
the ultimate consequence of  salinization of  arid agricultural lands.
In cases of  the occurrence of  a shallow groundwater table, salinization affects the soil's infiltration 
capacity, which creates flood risks at different scales. Flooding can lead to the damage of  roads, 
dams, agricultural fields and wetlands as well as the destruction of  buildings.
Salt accumulation can cause damage to infrastructure including roads, buildings and other 
constructions. If  the groundwater table occurs at a depth of  less than 1-2 m, the presence of  salts in 
the ground can cause a significant decrease in road tarmac durability. Salts also cause the corrosion 
of  asphalt, concrete and brick constructions.
Soil salinization results in significant limitations to agricultural crop production and, therefore, 
negatively  affects  food  security.  The  salinity-induced  losses  of   yields  within  dry  territories  vary 
from 18 - 26% to 43% [25], which can undermine the quality of  life for local people and aggravate 
damage caused by land degradation and climate change. The annual loss of  agricultural productivity 
is estimated to be 31 million USD, while the financial loss due to land abandonment following soil 
salinization, infrastructure deterioration and a lack of  water for soil leaching is estimated at 12 
million USD (World Bank, 2009).
The current trends of  climate change with increases in the frequencies and severities of  droughts 
represent a serious threat and create significant risks for fragile ecosystems in arid and semiarid 
areas. Droughts accelerate and spread the processes of  salt mobilization and accumulation within 
the upper horizons of  soils. More frequent droughts with extremely high temperatures and low 
humidity are especially dangerous in combination with a lack of  water for land irrigation, which 


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Chapter 1.Salt-affected soils of the Eurasian Region: diagnostics, criteria and distribution 
causes the suppression of  seedling growth, partial or complete losses of  yields over vast areas of  
soils affected by salinization. For example, a severe drought in the lower reaches of  the Amu Darya 
River in 2000-2001 caused losses of  yield of  14-17% in cereal crops and from 45- 52% to 75% in 
other crops. Orchards and vineyards are especially prone to yield loss due to soil salinization and a 
lack of  water. A lack of  water also affects the productivity of  cattle, as the poorer quality of  fodder 
crops causes a decrease in animal weight gain [8].
Efforts to prevent soil salinity should be directed at changing the land use and management towards 
decreasing the risks of  soil salinization in fragile agricultural environments during certain periods 
of  time. The assessment of  risks of  irrigation salinity can be useful in designing management 
techniques for different ecosystems. Comparing such risks can help in prioritizing the management 
options.
1.4. Distribution of salt-affected soils within the Eurasian Region
Salt-affected soils occur in almost all countries of  the Eurasian Region (Fig. 1.3). Soils with sulphate-
dominated salinity are most widespread (Fig. 1.4). According to calculations based on the digital 
map of  saline soils of  the Eurasian Region [16], the total area of  salt-affected lands is estimated 
at about 242 million hectares. Such lands are found mainly in Kazakhstan, Russia, Turkmenistan, 
Uzbekistan, Ukraine and Azerbaijan. There are very few saline soils in Armenia, Georgia, the 
Kyrgyz Republic and Moldova. The data on saline and alkaline soils in the Eurasian Region 
countries are presented in Annex A. Brief  notes on some countries are given below.
In  Azerbaijan  (B.G.  Aliev  and  S.A.  Safarli,  2016)  salinization  affects  about  633.8  thousand  ha 
(43.8%) of  irrigated lands, of  which 429.8 thousand ha (68%) and 139.8 thousand ha (22%) are 
assigned weak and medium grades of  soil salinity and about 66.2 thousand ha (0.4%) are strongly 
saline soils, the latter being found mostly within the Kura-Aras Lowland.
In Georgia (E. Sanadze, 2016) there are two large groups of  salt-affected soils, Solonchaks and 
Solonetz, with a total area of  112.6 thousand ha (1.6% of  the country). These are found mostly 
within the zone of  dry subtropics on plains, especially in Alazani, Eldari and other regions.


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Soil salinity manаgement manual | Part I.Soil salinity management in the Eurasian Region 
In the Republic of  Moldova (B.M. Ropot, Yu.G. Rozloga and other specialists) the main areas of  
distribution of  saline soils are located on the floodplains of  internal and transboundary rivers, 
where 180 out of  the total of  250 thousand ha of  saline soils are involved in agricultural use. As a 
result of  river damming, the floodplain environments are gradually turning into steppe, which is 
accompanied  firstly  by  the  acceleration  of   evaporation-induced  salt  formation  within  the 
groundwater – soil system and then by the intensification of  soil solonetzization processes. An 
analysis of  hydrogeological data shows that about a half  of  the area of  cultivated alluvial soils of  
the Republic has an unsatisfactory agricultural state, with the soils being affected by the processes 
of  salinization, solonetzization and slitization (reversible cementation of  clay soils).

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