Geographic Zones

Water

Domestic Animals

Domesticated plants in Afghanistan

Fauna in Afghanistan

Medical Plants in Afghanistan

Calenders used in Afghanistan

The diverse geographic zones of Afghanistan are discussed from the point of view of total ecology, emphasizing lines of human contact and communication in reference to zones of accessibility and relative inaccessibility.

The Danish geographer Humlum (1959) divided Afghanistan into ten natural provinces: East, South, Central, West, Northwest, North, Nüristan, Badakhshan, Wakhan, Monsoonal Afghanistan (Map 2-B). Those who wish to savor Humlum's fine work and detailed descriptions of the geographic areas are invited to consult his volume, and recommended to read Michel's review (1960), in which he primarily disagrees with, the inclusion of Jalalabad in Monsoonal Afghanistan. Michel feels that Jalalabad, with less than eight inches of rainfall, almost dry summers, and infrequent frosts, should, on the Koppen-Trewartha system, be called "subtropical steppe, dry summer" (Michel, 1960).

Climate varies considerably, both diurnally and annually. Generally, however, Afghanistan has hot, dry summers and cold winters with heavy snowfalls in the mountains. In November, the snow line begins In creep down the mountains, and stops at about 6,000 feet (1,830 meters) above sea level. Average annual precipitation registers less than 13 inches (21 centimeters). Extremes vary from about two inches (3.2 centimeters) in the southwestern deserts to 13 inches (21 centimeters-plus) in the eastern part of Afghanistan. Maximum precipitation, about 36 inches (58 centimeters) annually, occurs in the Salang Pass area. The wettest months occur regionally at different times during the year, a phenomenon related to location, elevation, and exposure. Much of the rain falls during the winter months (December to February). In the Kabul Valley, however, summer Indian monsoons occasionally push rains into the area. Precipitation increases with elevation, and most water resources of Afghanistan result from the melt waters flowing out of the Hindu Kush.

From November to March, snow blankets the mountains. Peaks over 18,000 feet (5,500 meters) are permanently snow-covered and several sizable glaciers still exist in northeastern Afghanistan. When snow begins to melt in March, the rivers begin to rise. Seasonal fluctuations occur simultaneously because the rivers get their waters from the same geographic source. Most rivers have maximum flow in the spring and minimum in summer, autumn, and winter. The major exception, the Wakhan Corridor, has maximum melt in late August, and daily fluctuations are spectacular. Small, fordable streams in early morning become torrents in the late afternoon, as water from snow melted by the midday heat flows down to the high valley plains of the Wakhan.

In many instances, minimum precipitation means drying up, or reduction of a river to a series of isolated pools in the streambed. At times, premature warm weather or sudden rainstorms cause flash floods, which catch and destroy whole semi-nomadic or nomadic camps as they pause seasonally in arroyos. Such a flash flood caught Alexander the Great during his invasion of the Afghan area (Burn, 1962).

The Eleven Geographic Zones

The first six zones (the Wakhan Corridor.-Pamir Knot, Badakhshan, Central Mountains, Eastern Mountains, Northern Mountains and Foothills, Southern Mountains and Foothills) relate to the. Hindu Kush Mountain system, young rugged ranges (like the Rocky Mountains) with sharp peaks, deep valleys, and many almost impenetrable barriers. The remaining five zones (Turkestan Plains, Herat—Farah Lowlands, Sistan Basin—Hilmand Valley, Western Stony Deserts, . Southwestern Sandy Deserts) embrace the deserts and plains, which surround the mountains in the north, west, and southwest.

The Wakhan Corridor and the Pamir Knot:

This unique area belongs geographically to the greater PatUir Mountain system. The Anglo-Russian Boundary Commission of 1895—96 politically force4 this zone on Amir Abdur Rahman Khan, so that at no point would British India and Tsarist Russia touch.

Many writers indiscriminately lump. the Wakhan Corridor and the Pamir Mountains together and fail to distinguish between the sub-zones. In reality, the Corridor is one geographic entity and the Pamir Mountains another, although the Wakhan leads directly into the Pamir. I have been reminded (Michel, 1968) that "Pamir" actually refers to the high and relatively flat valleys between the mountain ranges, where the Kirghiz graze their flocks.

Two relatively wide valleys exist in Wakhan: one at Ishkashim (two miles across, three miles long); another at Qala Panja (less than a mile in all directions).

"Pamir Knot," although scientifically unacceptable to many, aptly describes the fist-like ranges which pivot off the Karakorum, Kunlum, and Himalayan mountains, shifting the trend from roughly southeast— northwest to northeast—southwest through Afghanistan. According to Humlum (1959, 17) 82.9 percent of the Wakhan—Pamir area is above 10,000 feet (3,000 meters), and 17.1 percent between 6,000 and 10,000 feet (1.800 to 3,000 meters). Perpetual snow covers all the Pamir above 16,500 feet (5,000 meters) above sea level. Many glaciers nestle at the higher elevations. Blue-green glacial lakes, such as Sar-i-Koll, shimmer. Passes thread through the high mountains at between 11,500 and 14,800 feet (3,500 to 4,500 meters), often 1,700 to 3,000 feet (500 to 1,000 meters) higher than the valley bottoms (Humlum, 1959,112).

Mountain climbing in the Hindu Kush has increased considerably during the past few years. Several recent expeditions have climbed many peaks in the mountains south of the valley of the Ab-i-Panja (border with the USSR), which later becomes the Amu Darya. In 1965, for example, at least twenty major foreign expeditions, including groups from West Germany, Japan, Poland, the United States, the United Kingdom, Czechoslovakia, Austria, and Italy, climbed mountains in the Afghan Hindu Kush.

Travel in the Pamir, which begins east of Qala Panja, is difficult, even with the hardy yak used by the Kirghiz nomads. In the sparsely populated Wakhan along the Ab-i-Panja, the people use the Bactrian (two-humped) camel and the horse. An unpaved, natural road follows the high, alpine valley of the Ab-i-Panja from the entrance of the Wakhan to Oak Panja. Trucks occasionally travel between Ishkashim and Qala. Panja and a Land Rover can breeze along the road at fifty kilometers an hour.

Often, however, the river narrows to less than one hundred yards and the ubiquitous Soviet watch towers stretch to cast shadows on Afghan soil, which accounts for the Afghan reluctance to permit foreign visitors to hunt in the home of the Ovis polii (Marco Polo sheep). Incidentally, evdn Russians have difficulty visiting the Pamir, because of the Afghan—Chinese border.

Several seasonally closed passes lead from Wakhan to Hunza and Chitral in Pakistan: Baroghil Pass; Dorah An (called Kach in Pakistan) Pass. The Kilik (or Wakhjir) Dawan leads from Kashmir. into Chinese Sinkiang and on to Tiwa and Urumchi, following former important trade and communication routes traveled by Marco Polo and earlier a flanking force of Genghis Khan, among others. In August 1969, the Pakistanis, in cooperation with the People's Republic of China, reopened an old route between Chinese Sinkiang and Gilgit, which can be utilized only seasonally, however.

Badakhshan:

Geographically, Badakhshan stretches from the entrance of the Wakhan to Kotal-i-Anjuman in the south and west, with the Amu Darya as boundary to the north. The Ab-i-Panja flows to the north near Ishkashim (entrance to the Wakhan) and cuts a large salient out of Central Asia as it patiently makes a parabolic swing to the west and south, thus avoiding the northeast mountains of Badakhshan.

High elevations over 10,000 feet (3,000 meters) constitute 27.5 percent of the terrain; 6,000 to 10,000 feet (.1,800 to 3,000 meters), 36.2 percent; 2,000 to 6,000 feet (600 to 1,800 meters), 32 percent; 1,000 to 2,000 feet (300 to 600 meters), 42 percent, as one approaches the Turkestan Plains (Humlum, 1959, 17).

The sharp, rugged Koh-i-Khwaj a Mohammad range in northern Badakhshan has been cut in many places by the Kokcha River 30 to 80 feet (9 to 25 meters) into the rock of the valley floor. The steep mountain slopes are covered with rockfall and talus. In the river valleys, up to three series of stream-laid gravel terraces occur, often cut several times by recurrent, spring melt-water floods.

An inhospitable but beautifully sculptured region, Badakhshan consists mainly of metamorphic and plutonic rocks, dissected by V-shaved valleys, which funnel most life into narrow trails.

Several of the open valleys surrounded by mountains and watered by streams, but mainly by springs, appear to have been glacial lakes during the Late Pleistocene, One such series of valleys lie west of Kishm, just north of the great mountain, Takht-i-Sulaiman (Throne of Solomon).

Several significant lakes exist in Badakhshan, the subject of many learned papers by British explorers in the nineteenth and early twentieth centuries. Thousands of nomads gather at the largest, Lake Shewa, in the summer, and return to the Turkestan Plains (near Chahar Darra, west of Kunduz) or eastern Afghanistan (Laghman), in the winter. Most Laghman nomads, however, go to the Central Mountains in the summer.

Central Mountains:

The Central Mountains (mainly the Central and Western Hazarajat) extend roughly from Shibar Kotal through the Koh-i-Baba range. A series of passes leads across this great range, crossed by many conquerors, including Alexander, Genghis Khan, Babur, and Tamerlanc. The two major passes are Shibar and Salang. No motorable road went through the Hindu Kush until the reign of King Mohammad Nadir Shah (1929—33), when the Afghans completed a long-time dream by building a road, which traveled circuitously via Shibar Pass through the Hindu Kush. The road followed the Ghorband and Surkh Ab river valleys for most of its course. But a major engineering miracle occurred in the late 1960s when, with Soviet financial and technical assistance, the Afghans constructed a tunnel through the heart of the Hindu Kush, just south of the summit of Salang Pass at an altitude of 11,100 feet (3,363 meters) above sea level

West of Shibar Pass, the Koh-i-Baba mountains, backbone of Afghanistan and a rugged, barren elevated tableland, contain sources of several of the country's more important river systems: the Kabul, Hilmand-Arghandab, and Han Rud.

The highest peaks in the Central Mountains vary between 14,000 and 17,000 feet (4,270 and 5,180 meters), with the summit of the Koh-i-Baba range at Shah Foladi, about twenty miles from Ak Sarat Pass. Slopes on the north are gentler than those to the south.

Talus covers the lower mountain slopes of the Hindu Kush and the river valleys are choked with boulders and gravels laid down in winter and moved along with great rapidity by spring snow melt. The few wide valleys are usually inhabited and cultivated or, if at high altitudes, used as summer grazing lands for livestock. These high altitude summer pasturelands are usually called yilaq.

Eastern Mountains:

The Eastern Mountains (as well as the others in Afghanistan) were presumably subjected to the same orogenic movements which uplifted the Himalayas proper (probably during the Middle Tertiary and later, or between 15 to 40 millions of years ago), folding and distorting the original sedimentary deposits, laid down in the Tethys Sea and extensive Middle Eastern Mesozoic (70 to 225 millions of years ago) marine basins.

At times, the uplifted mountainous areas were subjected to intensive glacial and fluvial erosion during the Pleistocene (Ice Age), which began about a million or a million and a half years ago. In addition, repeated tectonic stress during the mountain building movements created great fault systems. Most valleys (such as Ghorband, Kabul, Panjsher) are marked by fault lines created chiefly by Alpidi (Tertiary) movements. Although many valleys are narrow, some wider intermontane basins do permit agriculture. Frequent earthquakes, about fifty shakes of varying intensity per year, still occur.

To call the mountain systems of Afghanistan tortured is not trite, but concise.

Four major valleys dominate the human geographic patterns of the Eastern Mountains.

Kabul (an area of high level basins, with altitudes varying from 5,000 to 12,000 feet—1,500 to 3,600 meters—filled with probable Neogene and Pleistocene sediments) is surrounded by mountains of old rugged crystalline and metamorphic Palaeozoic rocks. The Paghman Range sits northwest of Kabul, with the Safed Koh to the southeast and the Kohi-Baba rising in the west. The Kabul River flows through Tang-i-Gbaru, one of the more spectacular gorges in Afghanistan, to Salalabad.

The second major valley, Kohistan—Panjsher, includes the wide basin of Koh Daman and Charikar and leads to the steepsided valleys of Nijrao and Tagao, where farmers practice terraced agriculture. This region consists mainly of faulted, dissected limestone, with some intrusive epliolites bordered by gneisses and igneous rocks in the east.

The Panjsher Valley serves as a major note-south route used by nomads summering in Badakhshan and wintering in the Laghman— Jalalabad area. Until 1961, many of these groups crossed the border into Pakistan to winter in the Peshawar Valley and points south.

The third major valley, Ghorband, lies in an east—west trend from Charikar to Shibar Pass. Here the sedimentary basin is flatter and with higher terraces than the Panjsher. Farther, west, near Bulola, limestone, and near Bamiyan, sandstone and conglomerate, cliffs are encountered, but farther east, the formations become increasingly undifferentiated metamorphic.

Nuristan (formerly called Kafiristan)

A region of wild, narrow mountain valleys, accessible only by foot trails except on the periphery where new roads have been constructed, consists of five major north—south valleys (from east to west: Bashgal-Landai Sin-Kunar River complex; Waigal; Pekh-Parun-Kantiwa; Alinga-r-Kulam; Darra-yi-Nur), and about thirty east—west lateral valleys leading into the major valleys. Nuristan is a complex country of gneisses, dioritic and granitic pegmatites, undifferentiated metamorphics, some -Mesozoic limestone beds, slates, and recent deposits in the valleys. The five major north—south valleys (Bashgal, Waigal, Pech, Alingar, Alishang) support streams which swell the Kunar River as it flows southwesterly until it joins the Kabul River. Many passes lead into Nuristan from all directions.

In addition, Kotal-i-Uriai, a, relatively easy pass, leads from Kabul into tile eastern Hazarajat. Several passes lead from Paktya into the Kurram Valley of Pakistan, through Parachinar to Thal.

Snow usually begins to fall in October, blocking most mountain passes for at least part of the winter. The permanent snow line varies between 10,000 and 12,000 feet (3,000 and 4,600 meters) above sea level. The winter snow line creeps down to about 6,000 feet (1,800 meters). Even hi the summer, snow flurries occasionally occur at altitudes above 12,000 feet (3,600 meters). Snow fields and permanent glacier breed unfavorable conditions in some areas above 14,000 feet (4,300 meters).

Blizzards dominate the winter months, and snow blocks most passes above 7,000 to 8,000 feet (2,100 to 2,400 meters). Systematically accurate snow depths are not available, but drifts of ten' feet (three meters) and deeper have been reported. Winds accompanying winter storms reach gale proportions and continue to slice down the valleys, even when not transporting snow. Strong steady winds also occur in spring, summer, and autumn, especially in the higher altitudes, but are less hence below 6,000 feet (1,800 meters). The local population knows all the seasonal winds and has names for the more vicious and gentler ones.

In the spring (March-May), the snowmelts and rushing streams become raging torrents. The winter months (December—March) are intensely cold and snowy in the Eastern Mountains, although much less snow falls in the main basins, such as Kabul, Kohistan, and Ghorband. Temperatures average around freezing but sometimes drop as low as 10F. (-30⁰C.).

Spring temperatures increase tremendously. Freezing weather is found in April in the highest passes, but below 7,000 feet (2,100 meters) temperatures are more comfortable, averaging 55⁰ to 65⁰F. (130 to 180C.) at noon. Actually, the high, dry, sunny climatic face of Afghanistan is more often comfortable than not in habitation areas. May is seasonally warm up to heights of 11,000 feet (3,350 meters), though the temperature fluctuates and freezing weather does occur.

Summers are relatively warm and comfortable. Autumn (October—November) brings intense cold to heights above 6,000 feet (1,800 meters). Snow filters down on - the northern slopes, while the southern slopes still have warm (55⁰F. or l3⁰C.) days. Changes in altitude as well as season produce great temperature differences. A descent from 11,000 feet (3,350 meters) to 5,000 feet (1,520 meters) can involve a 700 to SOW. (210 to 26"C.) change in a few hours. High in the permanent snowfields and glaciers, day temperatures can be warm (up to 65⁰. or 18⁰C.) if no winds blow. The wind-chill factor becomes important as altitude increases.

Even when there is no snow lying, - persons unaccustomed to high-altitude glare require sunglasses. Caravaneers consider western-style sunglasses as prestige items. Many1 however, still utilize homemade types similar to those made by the Eskimo: a strip of leather or wood with thin slits cut to limit the amount of sunlight striking the eye. In addition, the epicanthic eyefold of the Central Asian Mongoloid serves as a natural biological adaptation to protect the eye against snow and sun glare.

Nuristan and Paktya are the most heavily, forested areas in Afghanistan. 'The Panjsher Valley, as historical references attest (Le Strange, 1930, 350), had large forests until they were destroyed by the greedy hand of man, who cut down and burned' trees to smelt silver, copper, and other ores during the heyday of the early Islamic period before the thirteenth-century Mongol invasions. Man remained, but the forests never returned.

Modern vegetation patterns in the Eastern Mountains consist mainly of thin grasses and stunted bushes. Actually, about 40 percent of all Afghanistan is covered with sparse greenery.

There is a geographic anomaly, the so-called Reg-i-Rawan, an area of sand dunes, near Begram, just south of Charikar.

Southern Mountains and Foothills:

This region is formed as the river systems of the Kabul ant' Hilmand debouch into the plains, and semi-desert becomes desert, with agricultural villages studding the "toothpaste squeezes" of the rivers and tributaries. The area mainly embraces Qandahar, Ghazni; and much of Paktya.

Northern - Mountains and Foothills:

A broad zone of mountain plateaus and foothills north of the Hindu Kush watershed stretches from the 70⁰E meridian west to the Iranian border. Low, bare limestone, shale, and Sandstone Mountains with rounded summits dominate. Soils are usually thin and stony, except on lower, recent flood plains with silt, clay, and loess deposits. In winter and -spring these soils turn into deep muds.

The Band-i-Turkestan Range rises south of Maimana to heights of 11,000 feet (3,350 meters),and runs-almost due east—west for about 125 miles (200 kilometers). The northern slopes drop abruptly onto the Turkestan Plains. In the foothills a loessy-sand called chol covers the bare rock.

South of the Band-i-Turkestan Mountains lies the Murghab River valley, a rolling limestone region parallel to the mountains, and never more than six to eight miles wide.

To the east the Paropamisus (plus Koh-i-Changar and Firozkoh) -Mountains cut off Afghan - Turkestan from the high valleys of the Central Mountains, and are the northern extremity of the main watershed complex. The region, characterized by deep valleys and rounded summits, consists mainly of barren scarps of metamorphic rock with peaks upto 11,500 feet (3,500 meters).

East of the Firozkoh lie the Kunduz, Andarab, and Surkh Ab valleys, which vary from narrow gorges to broad flat-bottomed valleys. The Andarab Valley pushes east toward Doshi. Between Doab and Bulola, the Surkh Ab Valley moves through a series of narrow gorges. Above Bubola, the valley divides: Shibar Pass lies to the east, and Bamiyan, -Nil Kotal, and Aq Ribat to the west.

Turkestan Plains:

The northern foothills abruptly drop from 4,000 to 6,000 feet (1,220 to 1,830 meters) into stony plains about 1,200 feet (370 meters) above sea level.

The elevation drops less -than 1,000 feet (305 meters) in 50 miles (80 kilometers). Scattered dunes sometimes occur in the pebbly deserts and conversely. Sand drifts and dunes begin near Andkhui less than 20 miles or (32 kilometers) from the Amu Darya. To the east, near Khist Tapa, the sand pinches out about 2 miles (3.2 kilometers) from the Soviet border. The long, shifting dunes reach heights of 30 feet (9 meters). Almost level, the floodplain of the Amu Darya varies from 2 to 10 miles \3.2 to 16 kilometers) in width. Marshy, alluvial terraces, 10 to 20 feet (3 to 6 meters) high, often separate the floodplain from the desert. West of Termez, USSR, a number of islands dot the river. North of Tashkurghan and southwest of Andkhui sit expanses of salt flats which become wet marshes in winter, but dry, crusty zones in summer.

Much variability in temperature occurs in winter (December-February). A series of warm days (60⁰ to 70⁰F. or 15⁰ to 21⁰C.) gives way to a three- to four-week period of freezing weather.

Spring (March-May) exhibits great climatic variability. March and April temperatures often drop to freezing, and maximum readings for two consecutive days in May may vary as much as SOW. (28⁰C.). Snow, sleet, and cold rain fall, but the snow seldom sticks. Throughout the spring, average temperatures increase gradually. Daytime temperatures sometimes exceed 80⁰F (26⁰C) in March, 90⁰ (32⁰C) in April, 100W. (37⁰C) in May.

Diurnal summer - (June—September, the least variable of the seasons) temperatures still fluctuate greatly. Day temperatures often reach 105⁰F. (40⁰C.), with nights much colder. However, by the middle of September, nighttime freezing temperatures commonly occur.

Autumn (October—November), like spring, exhibits variable temperatures, and a shift from hot to freezing weather can strike abruptly.

Rainfalls sporadically in autumn and winter, but most fall in spring as thundershowers, increasing the danger of floods. Disastrous floods sometimes result as snowmelts in the mountains south of the plains during - April and - May. The average annual precipitation in the Turkestan Plains seldom reaches 10 inches (25.4 centimeters), however.

In late summer and early autumn soft winds from the north shift rich loess to the plains and foothills of north Afghanistan, permitting extensive highland agriculture. For centuries, this unscheduled aid program has been annually giving Afghanistan tons of topsoil from the Russian Central Asian steppes. The loess often seems to hang in the air, and penetrates everything, skin and clothing, with an almost oily consistency, and sometimes even blocks out the sun in the afternoon. Such windblown, natural phenomena, however, cause grasslands to flourish into farmlands and into seasonal flowering grasses to feed the flocks of the nomads.

Heart-Farah Lowlands:

Actually an extension of the Khurasan Region of the Iranian Plateau, the Herat—Farah complex consists mainly of mountain ranges and low hills, sporadically rugged but generally rounded, separated by broad, flat valleys. The area is approximately-enclosed by the Had Rud to the north, the Khash Rud to the south, and the Central Mountains to the east.

The region is intensively cultivated where water is available.

The low hills near Herat are crystalline rocks and undifferentiated metamorphic of the Upper Paleozoic, with Mesozoic limestones and shales north of the Had Rud. Mesozoic limestones and shales, Tertiary sandstones, clastics, and basic to intermediate volcanic intrusions and extrusions abound in the south. Desert basins of sandy clay covered with loose - gravels and pebbles surround the hills. Near the Irano-Afghan boundary exist a number of salt- and mudflats, more extensive than those of the Turkestan Plains.

Winter (December-February) finds freezing temperatures common at night. Warm spells do occur, however, and temperatures above 70⁰F (21⁰C) have been reported for December—January, and 80⁰F (26⁰C) in February. Spring (March—May), more variable than winter, has some freezing temperatures in March, but the average gradually increases to about 700F. (210C.) in May. Day temperatures in the hot, dry summer (June—September) sometimes reach 12⁰F (45⁰C.). A June midnight temperature of 12⁰F (45⁰C.) has been recorded at Farah, In September, a noticeable decrease in temperature occurs, and nights become chilly and even cold, although the days remain relatively warm. Transitional autumn (October—November) has decreasingly warmer days and increasingly colder nights, especially in the Herat 'area.

Annual precipitation averages 7 inches (18 centimeters) in Herat. Both snow and rain fall in the Herat area during winter, but snow melts and seldom remains on the ground for long. Although Less rain falls in the spring, rivers swollen with melt-water often cause floods as early as February and climax in April. Summer thunderstorms and flash rains occur, but autumn is almost rainless.

Hilmand Valley-Sistan Basin:

Most of the low lying (average elevation about 1,700 feet, or 520 meters) Sistan Basin lies in Iran. The eastern boundary of the Sistan Basin penetrates the edge of the Dasht-iMargo ("Desert of Death") along a sharp scarp with the height varying from 30 feet (9 meter) to several hundred feet. The Sistan Basin, a zone of intermittent lakes, fresh water and brackish marshes interspersed between stony and sandy deserts, forms a part of the great inland Hilmand drainage basin. The river flows into the Hamun-i-Hilmand, a-series of marshes and connecting lakes. Fresh water overflows from the Hamun, and empties into the Gaud-i-Zirreh, an ephemeral brackish lake.

Level, fertile plains, the ancient beds of extinct lakes, surround the modern lakes. A numbct of volcanoes erupted in the early Pleistocene, covering much of the bottom with lava flows and caps. In well-exposed vertical sections, several layers of Neogene and Pleistocene sediments can be differentiated. Reddish- and greenish clay alternate interspersed with bands of gravels and -sands. Gravel deposits and fine silts overlay the clays. -

Spring floods often cover wide areas, and the uncontrolled Hilmand flushes downstream from the mountains. But the huge dams at Kajakat on the Hilmand and Dahla on the Arghandab have helped gain moderate control since the mid-1950s.

Tamarisk bushes grow in abundance along sections of the Hilmand flood plain not utilized for agriculture The Afghans call such tamarisk groves, where wild boar still thrive, Jan gal (jungle).

The vicious bad-i-sad-o-bist-roz ("wind of 120 days"), a seasonal natural phenomenon, emphasizes the inhospitability of southwestern Afghanistan. Born of the differential pressures between the northern plains and the southern and southwestern lowland deserts, and - blocked by the Central Mountains of Afghanistan and the Elburz of Iran, the winds whip down the natural corridor along the Irano—Afghan border, stirring up violent sandstorms from Herat to Pakistani Baluchistan. Velocities - vary from day to day and week to week, but sometimes exceed 100 knots. Beginning in July, the winds gradually increase and blow through September.

Other strong, cold winds push out of, the high-pressure areas south of Central Asia and the Turkestan Plains in autumn, winter, and spring, but seldom with the force of the bad-i-sad-o-bist-roz.

Another phenomenon of the lowlands of Afghanistan, both north and south, is the khakbad ("dust wind"), or small whirlwind of sand. At times, tens of these miniature tornados can be seen swaying across desert and semi-desert areas.

Western Stony Deserts:

Mainly uninhabited and - relatively unexplored, the Dasht-i-Kash, Dasht-i-Margo, and adjacent areas are hot, waterless, barren, varnished-pebble-strewn deserts, which (like the Southwestern Sandy Deserts) seldom rise over 3,000 feet (915 meters) above sea level, usually ranging between 1 and 3,000 feet (305—9 15 meters). Scattered lenses of volcanic ash a few inches thick alternate with volcanic lavas in the region. Spring flash floods cut deep depressions in the sandy clay and silt underlying the heavily cemented, blackish wind-polished basaltic pebbles. Seasonal overflow from the Hilmand creates shallow ponds throughout the fringes of the desert. -

Great diurnal changes of temperature occur, and water sometimes freezes at night in summer in spite of-noon maxima of 12⁰F (45⁰C), or higher.

Limited flora and fauna can survive in the Sistan Basin, Western Stony Deserts, or Southwestern Sandy Deserts. Desert plants are xerophytic and adapt to extremes of aridity and salinity. Only thorny, deep-rooted plants exist perennially. The commonest and most widespread is camel grass or thorn, a member of the pea family, which is greenish-gray in color. Camels grass exudes a combustible sap, which hardens on contact with the air and can be used as an emergency food. Some such manna must have assisted the Israelites in their trek through Sinai to Canaan. Camel grass itself can be used to quick-broil small -animals and birds, for it burns rapidly at a very high temperature.

Southwestern Sandy Deserts:

South and east of the Hilmand River lies Registan, the "Land of Sand," an area of shifting sand dunes with an underlying pebble-conglomerate floor. The moving dunes reach -heights of between 50 and 100 feet (-15 and 30 meters). However, some fixed dunes exist in central Registan. Level areas between the dunes, called pat (which also means desert in Baluchi) menaa travelers. Treacherous, sandy-clay mush when wet, pat becomes a hard-topped pan when dry, but remains mushy underneath.

The Hilmand system to the north and west, the Chaman-Qandahar road to the east, and the Chagai Hills of Pakistan to the south encloses the sandy deserts.