ENVIRONMENTAL FLOWS FOR FIGHTING AGAINST DESERTIFICATION IN ARID RIVER DELTAS

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3 ENVIRONMENTAL FLOWS FOR FIGHTING AGAINST DESERTIFICATION IN ARID RIVER DELTAS 3

4 OBJECTIVES Negative changes in the arid river deltas after runoff regulation of water flows and possible ways of mitigation or prevention of landscape desertification processes 4

5 Desertification of soils in the river deltas of arid regions becomes the largest ecological, economic and social problem. 5

6 Powerful degradation processes occur in deltas of the rivers which run into lakes and internal seas, for example, the river Ili The Ili River basin 1- plains; 2 inter-mountain valley; 3 foothills; 4 water area; 5 mountains. 6

7 In delta of the river Ili desertification processes are connected with a construction of the large (28 km3) Kapchagay water reservoir in the middle stream, and also intensive development of irrigation in China and Kazakhstan. 7

8 Long-term and seasonal distribution of the water discharge in the Ili River. It is became adverse for a delta flooding. 8

9 Long-term and seasonal changes in suspended solids in the Ili River shows that after runoff regulation the solid flow accumulated in the Kapchagay reservoir 9

10 Water regime of hydromorphic soils in the Ili River delta at desertification Soil indexes: Am alluvial-meadow, Sm swampy-meadow, Ms meadowswampy, S swampy, Tl takyr-like soils, Sn sands loose and poorly fixed, Sk solonchaks (saline soils). Texture of soils: 1 clay and heavy loam, 2 loam, 3 light loam, 4 loamysand, 5 sand. Forms of moisture in soils: 6 free water, 7 TMC-CMC (total moisture capacity capillary moisture capacity), 8 CMC-FMC (capillary water capacity field moisture capacity). 9 FMC-CBMC (field moisture capacity capillary-break moisture capacity), 10 CBMC-WMC (capillary-break moisture capacity wilting moisture capacity), 11 less WMC (wilting moisture capacity or wilting point). 10

11 Soil area changes in the Ili River delta at desertification Soil inde -xes Аt Аm Аm dr Аm des Sm Sm dr Sm des Ms Ms dr Ms des S Sk Tl Sn L (thousands of ha) Soils Alluvial-meadow tugai Alluvial-meadow Alluvial-meadow dried Alluvial-meadow desertificating Swampy-meadow Swampy-meadow dried Swampy-meadow desertificating Meadow-swampy Meadow-swampy dried Meadow-swampy desertificating Swampy Solonchaks Takyr-like soils Sands Lakes Years of survey Predict Total

12 Prognostic schematic soil map of the Ili River delta 1 sands in a combination with desertificating soils, sands in a combination with hydromorphic soils, 3 saline soils, 4 takyr-like soils, 5 desertificating soils, 6 alluvial-meadow tugai soils, 7a alluvial-meadow soils, 7b alluvial-meadow dried soils, 8a swampy-meadow soils, 8b swampy-meadow dried soil, 9a meadow-swampy soils, 9b meadow-swampy dried soils, 10a swampy soils, 10b swampy dried soils, 11 lakes. 12

13 But in 80s filling of the Kapchagay reservoir had been suspended and environmental flows to delta Ili were increased. 13

14 And in 90s (after disintegration of the USSR) water consumption had sharply decreased for irrigation in the Kazakhstan part of basin. All it was allowed to weakening degradation processes in Ili delta. 14

15 Zoning of the soil cover changes in the Ili River delta in Wetlands; 2-Soil drying-up & salinization; 3-Soil drying-up, desertification & salinization; 4-Wetlands desertification & salinization; 5-Soil desertification & salinization; 6-Coastal wetlands; 7-Desert soils of the ancient delta. 15

16 Preservation of hydromorphic landscapes For preservation unique hydromorphic the delta Ili landscapes it is necessary application of all measure complex for protection, rational use of water and soil resources in all basin, and also optimization of a runoff distribution in delta (so-called Integrated Water Resources Management) 16

17 In 60s of last century conditions for even more grandiose ecological accident in the Aral Sea basin were created. But the real ecological accident had burst in 80s when inflow of river water to the Aral Sea decreased for 48 km3 per year. Prompt desertification of hydromorphic landscapes had begun. 17

18 Soil area changes in the Syrdaria River delta 18

19 Syrdarya Delta (2002) 1-Soil drying up & salinization: 2-Soil desertification & salinization: 3-Soil drying up, salinization & desertification; 4-Meadow soil restoration; 5-Soil salinization & desertification; 6-Desert grey-brown soils; 7-Saltysand desert formation on the Aral Sea bottom. 19

20 Winter flooding in the Syrdarya Delta Last decade powerful winter flow allowances to the Syrdarya delta from the Toktogul reservoir were carried out. They caused flooding of the large areas. However these environmental flows have serious destructive action on settlements and economic objects in all Southern Kazakhstan. 20

21 Amudarya Delta (2002) 1-Soil drying up & partly salinization; 2-Soil drying up, desertification & salinization; 3-Soil desertification & salinization; 4-Soil salinization & desertification, with artificial water bodies; 5-Sandy desert on the Aral Sea bottom; 6- Salty desert on the bottom; 7-Water Desertification processes in the Amudarya delta as a whole are similar to that in the Syrdarya delta. But they are shown most sharply in the peripheral delta part adjoining the Aral Sea. 21

22 Amudarya Delta (VI-28) Comparison to the space image of 2008 has shown, that the deserted delta part has increased. Moreover, space pictures have shown how promptly the desertification area in the Syrdarya and Amudarya deltas has been extended at the expense of drying bed of the Aral Sea. 22

23 The Aral Sea Salt and dust transfer by the wind on the adjacent territory. Ecological accident in the Aral Sea basin has huge economic and social consequences. 23

24 The Aral Sea bottom In the arid climate conditions there are processes of desertification, salinization and eolian destruction in delta soils. Ships on the dryingup bed of the Aral Sea. 24

25 Heihe Delta (VI-16). The western China Experience of fighting against desertification in the river Heihe delta where for last decade degraded processes have been essentially weakened is very indicative. Thanks to the whole complex of water security measures called as Integrated Heihe River Basin Management, water has returned again to the most remote parts of the chain of deltaic enlargement. 25

26 Colorado Delta (IV-24) A situation in the river Colorado delta on the border of the USA and Mexico is interest. The irrigation of the huge areas in the Imperial Valley in the USA has caused powerful desertification and delta soil salinization. And only in the last time environmental flows to delta (1 km3) are carried out. Also salty waste waters from irrigated fields are directed to the lowering Cienega de Santa Clara where hydromorphic landscapes are formed. The newest space pictures of this region show, that these measures it is possible to restore hydromorphic landscapes (wetlands) only in a narrow strip along the river-bed of the Colorado and in the named bogged up and salted lowering. 26

27 Mesopotamia 2001 (XI) On an extent of decades intensive irrigation development in the top and middle reaches of the Euphrates and Tigris caused the most powerful desertification of huge territory in the lower reaches. Even recently well-known hydromorphic lands at merge of the rivers Euphrates and Tigris by 2001 had completely dried up, salted and degraded 27

28 Mesopotamia 2008 (V-24) But destruction of Iraq economy owing to the war had led to increase of water flow in lower reaches and to partial restoration of these hydromorphic landscapes. It is obviously, that such condition of these landscapes cannot be considered as a steady, and it is necessary to develop an action system for protection and rational use of water and soil resources in all basin. 28

29 Conclusion As a whole it is necessary to notice, that struggle against desertification in arid deltas of the rivers with regulated flow has already got considerable practical experience. Concrete results in technology of environmental flow applications, distributions of river water in deltas have been reached. 29

30 But at present time this experience is obviously insufficient. And abundantly clear, that struggle against desertification in arid deltas can be carried out only on a basis of the basin analysis of water and land resources usage, reconstruction of irrigating systems including basin irrigations, revision of all strategy of economic development in such basin. 30

31 Thank you very much for your attention 31

32 Yu. M. Popov, Ph. Dr., Ass. Professor Ecotera Ltd., Almaty, Kazakhstan V. M. Starodubtsev, Dr. of biology, Professor National Agricultural University, Kiev, Ukraine 32