DEPARTMENT OF WATER RESOURCES OF THE PYANJ BASIN ZONE

05:13:52

June    
Mon 27-06-2022

ENVIRONMENT OF THE BASIN

1.1       Natural Environmental Conditions

  1. The Pyanj River Basin is a substantially pristine natural environment, preserved because of its remote location and sparse density of population. Its mountains and steep river valleys are stark and rugged, and formidable. Key features of the natural environment (soils, forests, ecosystems, landscapes and protected areas) are described in following sections.
  2. Population centers in the Pyanj Basin in Tajikistan include Khorog in the upper basin, and the Vose-Kulyab region in the lower basin. In Khorog there is little industrial development, and the changes to the natural environment in the city area are largely due to the establishment of residential areas on the banks of the Pyanj River and its tributaries.
  3. In the Vose-Kulyab Region there is more significant change to the natural environmental conditions due to the extensive irrigated lands located in the plains there, and minor industrial development within the urban areas. There has also been pressure from the population on the hillsides around the population centers from livestock grazed on pasture lands, and from the felling of trees on the hillsides essentially removing all-natural forests from these areas. The alluvial floodplain of the lower Pyanj, and the floodplain of the Yakhsu and Kizilsu rivers have also been significantly impacted by the development of irrigated lands, farming and livestock rearing activities.
  4. Natural mineral resources of the basin are largely unexploited, with no large-scale mining activities yet developed.

1.2       Ecosystems of the Upper Reaches of Pyanj River

  1. Mountain ecosystems occupy altitudes from 600 to 7,000 m above sea level. In this zone are more than 90% of them. At the same time, water resources are formed in mountain ecosystems, they contain more than 80% of biodiversity. Mountain ecosystems include nival-glacial, highland-desert, meadow-steppe, forest, most of the water-coastal, ruderal, and sometimes urbanized ecosystems. It is estimated that more than 80% of the country’s natural water bodies are located in mountainous and highland areas.
  2. According to the National Strategy and Action Plan for the Conservation and Sustainable Use of Biodiversity (2003), the following types of natural ecosystems are identified in the highlands of the Pamirs:
  • Nival-glacial ecosystem occupies a significant part of the Eastern and Western Pamirs and has great climate-forming and ecological significance at the regional and global levels. This is where the main water resources of Central Asia are formed. Despite the severity of climate, 17 plant species and 180 animal species inhabit this ecosystem.
  • Highland-desert ecosystems occupy mainly the vast territories of the Eastern and Western Pamirs. They are used as summer pastures. The plant cover of these ecosystems is dominated by eurotia, wormwood, Ajan spruce, white locoweed, feather grass and thorn cushion plant formations. These types of plants mainly maintain ecological balance and are forage lands.
  • The highland meadow-steppe ecosystem is distributed on all mountain ranges of Tajikistan and is of great economic importance. Most of the territory of this ecosystem is inhabitation to rare endemic species of plants and animals. The productivity of grass stand in meadow and meadow-steppe ecosystems is 5-6 times higher than in other ecosystems. However, in places of grazing, the ecosystems are highly degraded (more than 30% of the territory), the productivity of the grass stand has decreased from 20-25% q/ha to 10-12 q/ha.
  • The middle mountain coniferous-forest ecosystem covers about 50% of the total forest cover of the country. In the project area, this ecosystem is represented only in the Western Pamirs. Juniper forests and thin forests have water regulating, water conservation, slope-soil-saving and anti-mudflow value. According to the forestry authority, the slope areas of juniper forests and thin forests are annually reduced to 3%.
  • The middle mountain mesophilic-forest ecosystems are represented by maple-walnut, willow-poplar-birch forests with thin forest mesophilous shrubs. The project area is also located in the Western Pamirs. These ecosystems are of great economic importance (fruits and berries) and support the ecological balance. They are favor the development of recreational areas.
  • Rare and endangered species of the flora of this ecosystem includes Ungernia Victor, Ostrowskia magnifica, kuziniya darvazskaya (кузиния дарвазская); the fauna includes lynx, snow leopard, urial, brown bear, Indian crested porcupine; of birds – pheasant, common pigeon, golden eagle, etc. Forest area ecosystems are reduced annually, but adequate restoration work is not conducted.

1.3       Ecosystems of the Lower Reaches of Pyanj River

  1. Ecosystems of the tugai complex are represented mainly in the floodplain lower reaches of the Pyanj and Vakhsh rivers. The ecosystems of the tugai complex are well preserved in the territory of the Tigrovaya Balka Reserve. There is also a large number of loop lakes, where large colonies of migratory birds are observed in winter. Amphibians are represented by the green toad and the lake frog. Of the reptiles, there is dice snake, steppe ribbon snake, blunt-nosed viper, Oxus cobra, mountain racer, Clifford’s rat snake, etc. Among the birds there are: white heron, bittern, common teal, marsh harrier, rail, waterhen, pheasant, common starling, black cormorant, kestrel, great reed warbler, rufous warbler, common reed bunting, Turkestan tit, kingfisher, roller, blue-cheeked bee eater, gull-billed tern, least tern, swallow, magpie, spotted flycatcher, Eurasian blackbird, red-backed shrike, white-rumped swift, common swift, snake eagle and etc.
  2. The typical mammals are: nutria, otter, wolf, wild boar, jungle-cat, Bukhara deer, porcupine, fox, striped hyena, badger, jackal, weasel, Asiatic bandicoot rats, Turkestan rat, house mouse, hare gerbil, hedgehog rat, Turkestan rat, house mouse, tamarisk gerbil, mole vole, tolai hare, eared hedgehog, common pipistrelle, common serotine, Hemprich’s arrow-eared bat, etc. In the valley of the Pyanj River over the past decades, tugai area have sharply decreased. Meanwhile, the tugai complex performs a bank-strengthening, moisture-preserving function and is the main habitat of a number of unique animal species.
  3. The ecosystems of the desert and semi-desert landscape. A unique complex of animals is found in hot lowland deserts and plains. Ecological living conditions here are extremely high summer temperatures, poor vegetation, lack of moisture in the soil and air. Ecosystems of desert and semi-desert landscapes dominate mainly in the flood plain and the lower reaches of the Pyanj River at an average height of 300 to 500 m. Due to the limited amount of land suitable for development, in Tajikistan in recent years there has been an intensive water-supply and development of the ecosystems of this altitude zone.
  4. The typical reptiles are the Central Asian tortoise, steppe agama, sunwatcher, rapid fringe-toed lizard, saw-scaled viper, spotted desert racer, steppe ribbon snake, sandy agama, Transcaspian desert monitor, Turkestan plate-tailed gecko, and Caspian desert lacerta.
  5. The birds of the semi-desert ecosystem are represented by Eurasian tree sparrow, corbie, common crested lark, red-backed shrike, European black vulture, Eurasian nightjar, black-bellied sandgrouse, striated scops-owl, dikkop, houbara, common crested lark and chestnut-headed finch-lark.
  6. Of the mammals, the main species here are the Persian gazelle, fox, jackal, tolai hare, long-clawed ground squirrel, gerbil, jerboa, eared hedgehog, marbled polecat, Caffre cat, greater horseshoe bat, Buhara horseshoe bat, lesser mouse-eared bat, etc.
  7. The Piedmont-plain ecosystems are located on gentle mountain areas and include piedmont semidesert-desert, water-coastal, agroecosystems, urbanized and ruderal-degraded ecosystems. By the use regime these ecosystems are divided into natural and anthropogenous. Because of the inaccessibility, a large territory of the country is occupied by natural, relatively undisturbed ecosystems, but there are small fragments of them in easily accessible places.
  8. The middle-mountain xerophytic-thin-forests ecosystems consist of pistachio, regeleklinovnik (регелекленовники), nettle-tree, horsetail ephedra, and kalofashniki (калофашники) plant formations. Pistachio-woodlands in dry hot areas perform water regulating functions and are the best habitat for wildlife in arid zones. Due to the intensive use as pastures and hayfields, there is almost no natural regeneration in the pistachio woodlands. Significant areas (up to 80%) previously occupied by pistachio communities are overgrown with shrubs.
  9. The fauna of this ecosystem is much richer than of others. Large mammals are represented by the Persian gazelle (Gazella subgutturosa), urial (Ovis vignei bochariensis), wolf (Canis lupus), fox (Vulpes vulpes), reptiles – by Oxus cobra (Naja oxiana), Central Asian tortoise (Testudo horsfieldi) and others. Among the animals listed in the Red Book of Tajikistan, here live such species as: markhoor (Capra falconeri heptnerii), urial (Ovis vignei), wild boar (Sus scrofa), Eurasian badger (Meles meles), fox (Vulpes vulpes), lynx (Haus felix), blunt-nosed viper (Vipera lebetina), cobra (Naja oxiana) tian-shan brown bear (Ursus arctos), Central Asian otter (Lutra lutra), rock pigeon (Coluba palumbus), chukar (Alektoris kakelik) and many others. Trout (Salmo trutta morfa fario) and marinka (Schizothorax intermedius) live in the rivers.
  10. Wild conspecifics are found in this ecosystem, such as: barley (Hordeum spontaneum), everlasting pea (Vicia tenuifolia), almond (Amygdalus bucharica), persimmon (Diospyros lotus), Chinese jujube (Zizyphus jujuba), pomegranate (Punica granatum), grapes (vius and vius) and others. In the Red Book, 39 species are listed, such as geerah (Bunium persicum), giant bell (Ostorwskia magnifica), Sophora, fissidens karate (Fissidens karataviensis), Korolkov saffron (Crocus korolkovii), Tulipa praestans, Vavilov almond (Amugdalus vavilovii). From species of medicinal plants grow kuchistan ferula (Ferula kuchistanica), Rosenbach onion (Allium rosenbachianum), common licorice (Glycurhysa glabra), sea buckthorn (Hippophae rhamnoides), yellow gowan (Taraxacum offisinalis), etc. Because of heavy cutting, they become secondary communities. Large areas of winter pastures, rainfed crops and human settlements located within these ecosystems lead to a reduction in the area of xerophytic thin forests.
  11. In order to preserve and sustain the use of this ecosystem, it is necessary to stop grazing in young pistache-woodlands, to create a preserved area to protect unique highly located communities and rare endemic species of animals (urial, markhoor, Persian gazelle and others).

2.          PROTECTED AREAS

  1. Protected natural territories and objects can be of international, national and local importance. The assignment of specially protected natural territories and objects to the category of international, national and local importance is made in accordance with legislation and decisions of Tajikistan. The following categories of specially protected natural territories are established:
  • state nature reserves, including state biosphere reserves;
  • state natural parks of national (national parks) and local significance (provincial parks);
  • state reserves of national and local significance;
  • state natural monuments of national and local significance;
  • ecological and ethnographic zones;
  • dendrological parks and botanical gardens;
  • natural, resort and health improving zones;
  • natural recreation zones.

2.1       Zoological Parks of National and Local Importance

  1. The legislation of the Republic of Tajikistan and decisions of state bodies may provide for other categories of specially protected natural territories and objects, as well as other territorial forms of protection of natural territories from adverse anthropogenic impacts. Protective zones with regulated and controlled regime of economic activity can be created on the adjacent areas.
  2. Specially protected natural territories are taken into account when developing forecasts, action plans, long-term plans for economic and social development, land management schemes and area planning.
  3. Three million ha of specially protected natural territories (SPNTs) make up approximately 21.58% of the territory of Tajikistan. Improving the management of existing 20 SPNTs is a much more urgent task than creating new SPNTs. The only exception is the creation of small state nature reserves to protect rare and endangered species and plant communities.
  4. The territory of the state nature reserve “Tigrovaya Balka” with an area of 49,786 ha, in 2011, was expanded to another 12,462 ha.
  5. In 2013, status of 12 of 13 natural reserves was expired, and extended only at the end of 2015. In 2013–2015, the unclear status of these territories led to increased pressure factors (for example, for pastures), with the result that, in some cases, condition of those pastures worsened.

2.2       National Parks and Reserves

  1. Tajikistan, having a relatively small area, has a sufficient and extensive system of specially protected natural territories (SPNTs). These are shown in the map in the following figure.

Figure 1: National Parks

  1. One of the most important functions of this system is the preservation of the country’s unique natural, historical and cultural heritage for future generations and its multiplication. As of 2019, all nature conservation areas of Tajikistan occupy a total area of 3.1 million ha or 22% of the territory of the country, and include 4 reserves with a total area of 173418 ha, 13 reserves on an area of 313,260 ha, 1 national park with a total area of 2.6 million ha, 1 historical-natural park on an area of 3000 ha and 1 natural park of 3805 ha. System of SPNTs of the Republic of Tajikistan covers almost the entire diversity of natural landscapes. Thanks to the system of protected areas, about 1,200 plant species, 85 mammal species, 10 thousand invertebrate species, 44 reptile species, 49 fish species, 346 bird species, many of which are of international importance, came under protection and control.
  2. Natural monuments, occupying small areas, are represented by various unique objects of nature and are taken under state protection. In total, 162 objects have been assigned this status in the country.
  3. The Tajik National Park was established in 1992. It is the largest specially protected natural area of the country (and in Central Asia): its area of 2.6 million ha is 18% of the total area of Tajikistan, 60% of the area of the Gorno-Badakhshan Autonomous Region. The Tajik National Park was inscribed on the UNESCO World Heritage List in 2013, becoming the first World Natural Heritage Site in Tajikistan.
  4. The Dashti Dzhum Natural Reserve was organized in 1983 on the southern slope of the Darvaz Range, on the area of 19.7 thousand ha. The purpose of the organization of the reserve was the preservation of the latter in the territory of Central Asia of viable population of the morhur goats, as well as the Central Asian mouflon. The reserve is located in the Shurabad district of the Khatlon region of the country, which is located 40 km from the city of Kulyab and 240 km from the city of Dushanbe. The mountain massifs of Shurabad are scenic wooded hills and in some areas rocky terrain. The most pronounced feature of the area is the presence of a diverse flora and fauna, as well as unique landscapes. A special attraction of the region is the habitat of the morhur goat, whose population in the world is extremely limited. The task of the reserve is to preserve and increase the population of morkhur, listed in the International Red Book and the Red Book of the Republic of Tajikistan.
  5. The Tigrovaya Balka Natural Reserve was established in 1938, with the total area of 49,700 ha located in the very south of the country, at an altitude of 300-500 m. The reserve is organized to preserve the unique communities of the tugai forest. As a result, tugai forests remained on a relatively large area (more than 24 thousand ha). Unfortunately, tigers could not be preserved in the reserve, however, on the territory of the reserve, such animals as Bukhara deer, Persian gazelle, jungle cat, striped hyena, pheasant, as well as the usual representatives of the fauna of these places were successfully preserved.
  6. The Romit Natural Reserve was set up in 1959, on a total area of 16,200 ha. The territory of the reserve is occupied by rocky and stony landscapes at an altitude of 1176-3195 meters above sea level. One of the significant achievements of the reserve is the creation of an artificial population of Bukhara deer, the preservation of the gene pool of natural complexes. The reserve is located in the scenic Romit Gorge, near the town of Vahdat. The reserve is located more than 80 km from the city of Dushanbe.
  7. The Zorkul Natural Reserve was created in 2000 on an area of 87,700 ha and covers the territories of the Murgab and Ishkashim districts of the GBAO. The reserve is organized with the aim of preserving the unique East Pamir natural complex and practically the last fairly large breeding colony of bar-headed goose, which are listed in the International Red Book.

2.3       Land Use Changes and Catchment Degradation

  1. The development of large-scale irrigation systems within the lower Pyanj Basin date from the 1950s (the Chubek main canal was constructed in 1950, for example) and continued to be developed until the 1980s. This heralded the major land use changes within the basin, and the population growth where such developments occurred. Since the 1980’s investment in infrastructure development in the basin were drastically curtailed.
  2. Areas outside the extensive irrigation developments have not been significantly impacted by land use changes. Degradation of lands in the basin has occurred in places around centers of population – largely caused by overgrazing of livestock and removal of trees.

2.4       Water Quality

  1. The largely pristine nature of the Pyanj Basin means that in general chemical and bacteriological water quality are fully natural. These are not necessarily good quality, though.
  2. The key constraint on achieving good ecological water quality is the heavy sediment content of the rivers which are described in the following section.
  3. There is a significant issue of bacteriological quality of water around centers of population as treatment of sanitation effluent and livestock wastes is minimal at best. However, with low population densities, the impact of these problems is small through most of the basin. It is a greater issue within the lower Pyanj Basin.
  4. Data on quality of surface waters is only collected intermittently, with the data obtainable for the main Pyanj River shown in Table 4. The data (obtained from Center for Analytical Control of the Committee for Environmental Protection under the Government of the Republic of Tajikistan, and the Agency for Land Reclamation and Irrigation [ALRI]) indicates good general chemical quality, but the problems with suspended sediment and turbidity.

Table 1: Chemical Quality of Water in Pyanj River

Name of ingredients Unit Pyanj River
Allowable rate (mg/l) Number of points Number of samples In 2005 In 2015
Biochemical Oxygen mg / l 3.0         6       24 0.28 2.0
Dissolved oxygen mg / l winter-4.0

summer-6.0

        6       24
Ammonium Nitrogen, NH4 mg / l 0.39          6        24 0.005 0.003
Nitrite Nitrite, NO2 mg / l 0.02          6        24 0.008 0.01
Nitrate Nitrate, NO3 mg / l 9.1          6        24 0.03 0.23
Phosphates, PO4 mg / l 3.5          6         24 0.09 0.26
Chlorides, Cl mg / l 300          6         24 12.5 37.3
Zinc, mg / l 0.01          6         24 0.005 0.005
Mineralization mg / l 200.0 <200.0 <200.0
Suspended substances mg / l 1,000.0 3,000.0 3,300.0
Turbidity (max. annual) mg / l 150.0 1,920.0 1,950.0

2.5       Sediment Movement in the Pyanj River Basin

  1. Geologically, the Pyanj Basin topography is a recent landscape that is unstable and eroding rapidly. Slopes are steep, with significant rockfall and soil movement to the main natural drainage systems. This means there is a large rock and finer sediment flow within the runoff within the Upper Pyanj Basin. Measurements of sediment within the Pyanj River system have been few, and infrequent especially in recent years.
  2. Sediment deposition in small tributaries and surface slopes in the upper and middle parts of the basin occurred as a result of floods and mudflows containing fragments of rock. Roughly milled materials remained in the composition of the alluvial cone to the middle part of the river basin. In addition, part of the sediment, not deposited to the middle part of the basin, could accumulate in the riverbed, in a relatively wide valley or in a small flood plain. Moreover, lakes such as Sarez, Yashikul and Zorkul also give sediments from the upper reaches, which accumulate in the wide part of the main channel of the Pyanj River, or in its main channels.
  3. As described above, sediments are held in various ways and temporarily stored in the upper and middle parts of the basin. Consequently, a possible theory of sediment transport is that solid runoff formed in the lower part of the basin is transferred from a narrow valley through the Khirmanjo area and contributes to the accumulation of sediments on the alluvial fan of the river, in the Hamadoni district. Part of the sediment flowing through a narrow valley accumulates on the alluvial fan or is transported further downstream.
  4. The sediment transport capacity was calculated at the top along the edges of the river fan. According to calculations, the amount of sedimentation on the alluvial fan is estimated at approximately 5 million cubic meters. annually, which corresponds to sediment deposition per year with a thickness of 2 cm to 3 cm. (Source. Committee for Emergency Situation and Civil Defense under the Government of the Republic of Tajikistan). According to the record available at Khirmanjo Station, the maximum suspended sediment flow in the Pyanj River is observed in August and amounts to 2,767 kg/s (source. ALRI). This is illustrated in Figure 5.

Figure 2: Monthly Volume of Sediments in River Pyanj Measured at Kirmanjo

  1. A study of the sediment movement has been conducted in the vicinity of the Hamodoni alluvial fan (near the headworks of the Chubek irrigation system) in the lower Pyanj that was funded by JICA reporting in 2007, as part of the “Study on Natural Disaster Prevention in the Pyanj River” carried out by CTI Engineering for the Committee of Emergency Situations, dated December 2007.[1] This study reports a sediment balance to effectively the lowest point on the Pyanj River as shown in Figure 6 and in Figure 7.

Figure 3: Sediment Balance of the Pyanj Basin (JICA, 2007)

  1. Sediment movement in rivers is in part through bed load, and in part suspended load. Large particles and rock fragments and boulders move along the bed of the river, and smaller particles are suspended within the water of the river flow. In the Pyanj River, because the river systems are steeply falling and because of the high sediment inputs to the system from unstable slopes are so large, both forms of sediment transport present large problems in water resources management.
  • For irrigation systems using water from the Pyanj or its tributaries, the challenges include:
  • Engineering the off-take of water from the river system;
  • Management of the sediment suspended in the water.
  1. For the off-take, ideally a structure across the river would be built to control the water level at the off-take and allow proper management of the proportion of the river flow directed into the intake canal. In the Pyanj Basin such a structure across a river presents large construction and maintenance problems – in part because of the large sediment bed-load that would also need to be managed. Therefore, surface water irrigation intakes are uncontrolled, and locally engineered to divert water by moving material in the riverbed to make sure as much was as is needed can be directed towards the canal intake.

Figure 4: Sediment Movement through the Pyanj River Basin (JICA, 2007)

  1. Management of the suspended sediment load within the river water can be done in a number of ways:
  • Using sedimentation basins at the head of the canal system to reduce water velocities allowing sediment to drop out of the water, where is can later be removed;
  • Managing the velocities of water in the canals such that the sediment moves through the canal system to be deposited on the fields;
  • Regular maintenance of the canal system to remove sediment that has been deposited on the canal bed and sides in order to maintain the canal carrying capacity; and
  • A combination of the above.
  1. It should be noted that the suspended sediment deposited within canal systems is generally considered beneficial to soil development and can contribute to soil fertility and productivity.

[1] Downloaded from http://open_jicareport.jica.go.jp/pdf/11870730_01.pdf