Analytical procedure for physicochemical parameters of NDWC during 2015.
The Nara Desert Wetland Complex (NDWC) includes sandy dunes, steep hills and occupies low lying flat zones associated with different natural wetlands formed from the seepage of Nara Canal. These different wetlands are the major perennial source of water to the agricultural lands, local communities, wildlife and for grazing livestock. The NDWC encompasses more than 225 seasonal and permanent small, medium and large sized lakes/wetlands. The total area of Nara Canal is distributed about (108,960 hectares) which starts from Sorah to Head Jamrao. The NDWC was declared in 1972 as a Game Reserve area for the protection of wild animals. The NDWC is also recognized an important potential Ramsar Site. The different floral habitation in the Nara Desert consists of mostly drought resistant vegetation of phytoplankton, reed vegetation, herbs, shrubs and trees. The area is ecologically rich with the faunal biodiversity that includes zooplankton, invertebrates, fishes, amphibians, reptiles, birds, and small and large mammals. The NDWC has received high values for its economic, social, floral and faunal habitat, aquatic biodiversity since the local communities are directly or indirectly dependent on these natural sustainable resources. During the sampling of environmental parameters, most of the wetlands were determined to be seasonal and permanent freshwater, brackish and hypersaline lakes.
- Nara Desert wetland complex
- Nara Canal
- ecologically-sustainable resources
- environmental parameters
1.1. Nara Desert wetland complex (NDWC)
The Nara Desert Wildlife Sanctuary is located between 26°28° N and 68°70° N (Elevation 50–115 m) in the province of Sindh, Pakistan. The desert area is approximately 23,000 km2 semiarid, receiving most of its water 88–135 mm of annual rainfall sporadically during the season of monsoon. These wetlands have rich variety of floral and faunal life such, as various aquatic plant species and different animal species of fishes, amphibians, reptiles, birds and mammals. However, the region is of diverse ecological value for the biodiversity of plant and animal species. These wetlands are distributed in different districts which usually start from Ghotki, Sukkur, Khairpur and ends in Sanghar District [1, 2, 3, 4]. In the Nara Canal region, the ground water level usually varies around 76 mm. The capacity of recharging these wetlands in the region is very low due to low rainfall. The level of water table varies between 2.5 and 5 m. In the nearest lands to the Nara Canal, the water level increases up to 10–18 m. Most of the wetlands were developed from sand dunes while a few were developed by deposition of silt . Irrigation system on Nara Canal is contained from upper Nara between Sukkur Barrage to the south Jamrao Headwaters and includes major canals such as Jamarao, Mithrao, Khipro and Thar [1, 2, 3, 4, 5, 6]. The area is geographically part of the Indus Basin and is composed of alluvial sediments which are deposited by previous and current different branches of the rivers. The sediments of the area are carried by Indus River which have tertiary shale and limestone basement. The sediments are composed of acolin sands that have previously been deposited during the Pleistocene Epoch. The composition of soil is from sandy to loamy and some part of soil is scarcely made up with the loamy sands. The color of soils is generally from brown to gray brown with the 5–15% mixture of CaCO3. The soil is usually composed of nan-saline, non-sodic mixed with poor organic materials having range of pH from 7.8 to 8.4. The developing hypersaline wetlands are common due to the overflow from Nara Canal . The region is distributed with the sandy and steep hills which are locally famous as “patt”, “Tars” or “Tals”. The main source of water for the agriculture and other activities is Nara Canal which extends up to 4–5 km from both sides of canal  (Figure 1).
The area has high wind velocity with the huge amounts of shifting of sand hills and have high temperature with higher soil radiation in the summer and observed very short rainfall and high evapo-transpiration. In the Nara Desert the average minimum temperature is 20°C and the maximum temperature is 45°C. In the summer, the hottest months are from May to July, when the temperature increases from 45 to 51°C. In the winter season, the lower temperature ranges from 20 to 28°C for the months of December to January. In the region, the annual rainfall from 88 to 135 mm occurs during the months from July to September [1, 2, 3, 4, 6]. The region of NDWC includes about more than 225 small to medium and some large sized-wetlands; some of these are seasonal and most are permanent. The Nara Canal is the largest canal of Sindh Province and covers more than 108 million hectares. On the both sides of Nara Canal the area is covered with woodland, riverine forest, scrub and desert scrubs. In the region, the source of water for wetlands is the seepage from the Nara Canal [1, 2, 3, 4, 7].
The climate of the area is mainly arid having high temperatures and late summer rains observed. The seasonal rainfall is varied and is less than 250–300 mm and rainy season usually starts from June to September. Before the monsoon season, the average temperature is exceeding 45°C in the desert region and in the plains of NDWS the average temperature between 30 and 40°C. The wetland complex is recognized of great hydrological values as 98% Nara Canal water is used for agriculture and only 2% water is used for domestic and drinking purposes. The wetland complex of Nara Canal is 361.6 km long and 90–135 m wide. The maximum water depth of wetland complex is 7.5 m. The highest water discharges of Nara Canal are reported in the months of May–July and the minimum water flow in the August [1, 2, 5].
1.2. Socio-economic status of area
According to the census survey report of 2016, the total population of Nara Taluka is counted 160,985. The target area of Nara Taluka the total population can be estimated to be more than 60,000. The major communities are living in the area study are Baradin, Baloch, Chang, Shard, Syed, Rapper, Dashi, Maleah, Khaskheli, Channa, Sahta, Gopang, Bhurgari, Rind, Nizamani, Mirbahar, Khoso, Wassan, Deewan, Ibupoto, Kakepoto, Rajar, Mirani, and Macchi. From these communities, a few numbers of people are engaged in artisan work, trade, business and job in government departments etc. The Livestock and agriculture are the major source of income of local communities. Cotton and wheat are the main crops cultivated in the Nara while sugarcane, barely, oil seed, pulses, vegetable and fodder are also cultivated. The peoples of the area are living in the worst condition and they have least health facilities, drinking water, education and they do not have available basic life facilities. In spite of low productivity of area, the desert area sustains relatively higher human (1.05 m) and livestock (1.25 m) populations was reported, respectively. The livestock is the major source of income, meat and wool in the area. The overexploitation of vegetation by the grazing animals and the cutting of trees and shrubs for fuel purposes have resulted in environmental degradation that threatens the natural resources in this area. There is no developed transportation system in the Nara Desert. Due to low literacy rate in the area, there is a lack of employment opportunities .
1.3. Floristical and faunilistical assessment of Nara Desert wetland complex
In the region of NDWC the richest biodiversity comprises a mosaic habitat of sandy hills, canals, forests, agriculture fields, freshwater and hypersaline wetlands. The area has the richest plant biodiversity consisting of 160 plant species belonging to 118 genera and 45 families were recorded [8, 9, 10]. The seasonal crops include sugarcane, cotton, wheat, barley and sunflower. The major vegetation in the sandy habitats are Prosopis cineraria, Acacia niloticus, Salvadora oleoides, Dalbergia sissoo, Tamarix aphylla, Melia azedarach, Populus spp. and Calotropis procera [5, 6, 11, 12, 13]. In the Nara Desert, the various drought-tolerant plant species, such as cactuses and succulents (Agaves spp.), Aerva javanica, Calligonum polygonoides, Crotalaria burhia, Capparis decidua, Dipterygium glaucum, Tephrosia villosa, Aristida adscensionis, Cassia, Tephrosia uniflora and Cassia italic were recorded . In the zone of Nara Desert, a mixed vegetation of shrubs and plants, such as Typha spp., Hydrilla verticillata, Paspalum distichum, Polygonum hyaropier, Urticularia lotus, Nelumbium nuciferum, Desmostachya bininata, Phragmites karka, Saccharum bengalensis and Tamarix indica were also reported [5, 8, 9, 10, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23].
The region has been received the high socio-economic values for the local community which is dependent on the agriculture, livestock, fish farms and freshwater wetlands. In this area, the small to medium villages are scattered and their major economies are agriculture and livestock [1, 2, 5, 17, 24]. In this zone, the variety of different wild mammalian species includes Hemiechnus auritus, Caracal caracal, Felis chaus, Felis margarita, Herpestes edwardsi, Herpestes javanicus, Canis lupus pallipes, Vulpes zerda, Hyaena hyaena, Mellivora capensis, Manis crassicaudata, Gazella bennettii, Hyelaphus porcinus, Sus scrofa cristatus, Lepus tibetanus, Funambulus pennantii, Hystrix indica, Lutrogale perspicilletta, Lutra lutra and Prionailurus viverrinus [5, 25, 26, 27]. The NDWC has the richest biodiversity of native and migratory avian fauna of which more than 78 avian species were recorded [5, 7, 24, 25, 28, 29, 30]. From this region, two threatened species of Indian-backed vulture and houbara bustard were recorded. The indigenous bird species of myna, crow, sparrow, red-wattled lapwing, white-tailed plover, and stilt were commonly observed. Two bird species of large-pied wagtail (Motacilla maderaspatensis) and rock bunting (Emberiza cia) were the first time reported in this region . Some important bird species categorized by International Union for Conservation of Nature (IUNCN) Red List as Least Concern species include the Indian darter, black or red-naped ibis, ruddy Shel duck; as Vulnerable, the marbled teal, and as Near Threatened, the ferruginous duck [5, 23, 24, 28, 29, 30, 31, 32].
2. Material and methods
For the collection of data the study was carried out in Nara Desert Wildlife Sanctuary which is located between 26°28° N and 68°70° N (Elevation 50–115 m) in the province of Sindh, Pakistan For the collection of flora species, the direct method/observation was applied during the diurnal period. To collect the faunal species, the direct and indirect methods were applied. For the collection of important ecological data of floristical and faunistical species, the field work for diurnal and nocturnal surveys were conducted randomly.
For the various physicochemical parameters, water from 10 randomly selected stations from a few selected lakes of NDWC were sampled monthly from January to December 2015. The samples were collected from two different sampling sites of upper surface and lower bottom layers and were kept in (Van Dorn Plastic Bottles 1.5 liter) during the collection period. After the samples were kept in 10% nitric acid for 24 hours and rinsed with the distilled water. Water samples were mixed in acid-washed container, rinsed with distilled water, and then stored at 4°C for further analysis. For quality assurance, the samples were analyzed in duplicate through careful standardization and samples examined. Physicochemical analysis was performed by the standardized methods . Chemical properties of water samples including water temperature, depth, and transparency were measured with the Secchi Disk. The temperature was measured by a mercury thermometer immersed into a water depth of 15 cm for 2–5 mins. The pH was measured by of an Orion Model 420 pH meter. The EC, TDS, and Na parameters were measured by a WTW 320 conductivity meter. Alkalinity, hardness, Cl and phosphate were analyses conducted by the standardized methods as recognized by WHO . Titration method (2310) was used to measure Ca, HCO3 and HCO. Mg and K were analyzed by spectrometry. For the analysis of BOD and DO, the Winkler method and a Jenway Model 9071 Oxygen Meter were used, respectively (Table 1).
|pH||pH||pH Unit||pH meter|
|Electrical conductivity||EC||Mu/Scm||Conductivity meter|
|Total dissolved solids||TDS||mg L−1||WTW 320|
|Turbidity||Turb||NTU||Nephlometric turbidity meter|
|Calcium||Ca||mg L−1||Titration method (EDTA)|
|Magnesium||Mg||mg L−1||Titration method (EDTA)|
|Hardness||Hard||mg L−1||Titration (silver nitrate)|
|Alkalinity||Alkal||mg L−1||Titration (silver nitrate)|
|Chlorides||Cl||mg L−1||Titration (silver nitrate)|
|Sodium||Na||mg L−1||WTW (320)|
|Potassium||K||mg L−1||Titration method (EDTA)|
|Sulphate||SO4||mg L−1||Titration (2310)|
|Biological oxygen Demand||BOD||mg L−1||Winkler method|
|Dissolved oxygen||DO||mg L−1||Winkler method|
3.1. Ecological assessment: (Flora and Fauna)
Flora: In the region of Nara Desert a variety of different floral species of aquatic as well as terrestrial plants, herbs, shrubs and drought resistant plant species were recorded (Table 2).
|S. No#||Scientific Name||Common Name||Local Name|
|1.||Acacia nilotica||Thorn mimosa, Bubul||Bubar|
|2.||Dalbergia sissoo roxb||Sisu, Tali||Talehi|
|3.||Alhagi maurorum||Camel-thorn bush||Kandero|
|5.||Mimosa pudica L.||Chui-mui, Lajwanti||Sharam Booti|
|7.||Prosopis cinreria||Jamal gotha||Kandi|
|8.||Tamarind indica linn||Imli||Gidaamri|
|9.||Trigodela L.||Proshan, kakpie||Hurbo|
|13.||Ficus benghalensis L.||Banyan tree||Barr|
|14.||Ficus religiosa L.||Sacred Fig||Pipal|
|15.||Morus alba L.||White Mulberry||Toot|
|16.||Eucalyptus camaldulensis||Red Gum, Eucalyptus||Safedo|
|17.||Zizephus mauritiana Lam||Berry||Baer|
|18.||Salvadora persica L.||Peelu||Khabbar|
|21.||Pennisatum glaicum L.||Bajra||Bajhari|
|22.||Zea mays L.||Corn||Makai|
|23.||Desmostachya bipinnata||Dub, Halfa grass||Drubh|
|24.||Calotropis procera||Milk Weed||Akk|
|25.||Eruka sativa||Salad Rocket||Janmbho|
|26.||Opentia ficus indica L.||Cactus||Thohar|
|28.||Suaeda fruiticosa||Shrubby Seablight||Laani|
|29.||Citrullus colocynchis L.||Bitter Apple||Tooh|
|31.||Aerva javanica||Kopak Bush||Booh|
|33.||Crotolaria burhia||Burhia Rattlepod||Soma|
|35.||Aristida adscensionis||Sixweeks Threeawn||Lumb Gaah|
|36.||Cassia italic||Cassia, Golden tree||Ghora wal|
|38.||Teophrotia villosa||Creeping Thistle||Phoodno|
|41.||Paspalum distichum||Knotgrass||Naru Gaah|
|43.||Nyphaea lotus||White Lotus||Kanwal|
|44.||Polygonum hyaropier||Blake’s Knotweed||Anjbar|
|45.||Urticulara lotus||Water Lotus||Kanwal|
Fauna: Amphibians: In the Nara Desert three amphibian species belonging from two families of Ranidae and Bufonidae were reported (Table 3).
|S. No#||Scientific Name||Common Name|
|1.||Crocodylus palustris||Mugger crocodile|
|2.||Kuchuga tecta||Saw-back turtle|
|3.||Kuchuga smithi||Brown turtle|
|4.||Geoclemys hemiltonii||Spotted-pond turtle|
|5.||Canis aureus||Asiatic jackal|
|6.||Fellis chaus||Jungle cat|
|7.||Prionailurus viverrinus||Fishing cat|
|8.||Felis silvestris||Desert cat|
|9.||Vulpes vulpes||Red fox|
|10.||Lutrogale perspicillata||Smooth-coated otter|
|11.||Herpestes javanicus||Small Indian mongoose|
|12.||Herpestes edwardsi||Gray mongoose|
|13.||Axis porcinus||Hog deer|
|14.||Sus scrofa||Indian wild boar|
|15.||Funambulus pennanti||Palm squirrel|
|16.||Gerbilus nanus||Balochistan gerbill|
|17.||Hemiechinus collaris||Long-eared hedgehog|
|18.||Hystrix indica||Indian crested porcupine|
|19.||Lepus nigricollis||Desert hare|
|20.||Meriones hurrianae||Indian desert jird|
|21.||Mus musculus||House mouse|
|22.||Tatera indica||Indian gerbil|
|23.||Aspiderestes gangeticus||Indian soft shell turtle|
|24.||Lissemys punctate punctata||Indian flapshell turtle|
|25.||Naja naja naja||Indian cobra|
|26.||Echis carinatus||Saw-scaled viper|
|27.||Eryx johni||Indian sand boa|
|28.||Lytorhynchus paradoxus||Sindh awlheaded sand snake|
|29.||Platyceps rhodorchis||Cliff racer platyceps|
|30.||Platyceps ventromaculatus||Glossy-bellied racer|
|31.||Xenochrophid piscator||Checkered keelback|
|31.||Calotes versicolor||Tree lizard|
|32.||Trapelus megalonyx||Afghan ground agama|
|33.||Hemidactylus brookii||Yellow-bellied house gecko|
|34.||Hemidactylus brooki||Spotted Indian house gecko|
|35.||Cyrtopodion scaber||Keeled rock gecko|
|36.||Ophoimorus raithmai||Three-fingered sand-fish|
|37.||Ophoimorus tridactylus||Indian sand swimmer|
|38.||Eutrophis macularia||Bronze grass skink|
|39.||Varanus bengalensis||Bengal monitor|
|40.||Varanus griseus||Desert monitor|
|41.||Acanthodactylus cantoris||Indian fringetoed sandy lizard|
|42.||Bufo stomaticus||Marbled toad|
|43.||Hoplobatrachus tigerinus||Bull frog|
|44.||Rana cyanophlyctis||Skittering frog|
|45.||Tachybaptus ruficollis||Little grebe|
|46.||Podiceps nigricollis||Black-necked grebe|
|47.||Phalacrocorax niger||Little cormorant|
|48.||Phalacrocorax carbo||Large cormorant|
|49.||Phalacrocorax fuscicollis||Indian darter|
|50.||Ardea cinerea||Gray heron|
|51.||Ardea purpurea||Purple heron|
|52.||Ardeola grayii||Indian pond heron|
|53.||Bubulcus ibis||Cattle egret|
|54.||Egretta alba||Large egret|
|55.||Egretta intermedia||Intermediate egret|
|56.||Egretta garzetta||Little egret|
|57.||Egretta gularis||Reef heron|
|58.||Ixobrychus minutus||Little bittern|
|59.||Ixobrychus sinensis||Yellow bittern|
|60.||Tadorna ferruginea||Ruddy shelduck|
|61.||Marmaronetta angustirostris||Marbled teal|
|62.||Anas crecca||Common teal|
|66.||Aythya ferina||Common pochard|
|67.||Aythya nyroca||Ferruginous duck|
|68.||Aythya fuligula||Tufted duck|
|69.||Aythya collaris||Ring-necked duck|
|70.||Elanus caeruleus||Blackwinged kite|
|71.||Milvus migrans||Common kite|
|72.||Haliastur indus||Brahminy kite|
|73.||Accipiter badius||Central Asian shikra|
|74.||Butastur teesa||White-eyed buzzard|
|75.||Circus aeruginosus||Marsh harrier|
|76.||Falco tinnunculus||Common kestrel|
|78.||Francolinus pondicerianus||Gray partridge|
|79.||Francolinus francolinus||Black partridge|
|80.||Amaurornis phoenicurus||White-breasted waterhen|
|81.||Gallinula chloropus||Indian moorhen|
|82.||Porphyrio porphyrio||Purple moorhen|
|83.||Fulica atra||Common coot|
|84.||Charadrius leschenaultia||Greater sand plover|
|85.||Vanellus indicus||Redwattled lapwing|
|86.||Vanellus leucurus||White tailed plover|
|87.||Charadrius dubius||Little ringed plover|
|88.||Charadrius alexadrinus||Kentish plover|
|89.||Charadrius mongolus||Lesser sand plover|
|92.||Limosa lapponica||Bartailed godwit|
|93.||Tringa totanus||Common redshank|
|94.||Tringa stagnatilis||Marsh sandpiper|
|95.||Tringa nebularia||Green shank|
|96.||Tringa glareola||Wood sandpiper|
|97.||Tringa hypoleucos||Common sandpiper|
|98.||Gallinnago gallinago||Common snipe|
|99.||Calidris minutus||Little stint|
|102.||Himantopus himantopus||Blackwinged stilt|
|103.||Larus heuglini||Heuglin’s gull|
|104.||Larus brunnicephalus||Brown headed gull|
|105.||Larus ridibundus||Black Headed gull|
|106.||Larus genei||Slenderbilled gull|
|107.||Gelochelidon nlitica||Gull-billed tern|
|108.||Hydroprogne caspia||Caspian tern|
|109.||Sterna aurantia||Indian River tern|
|110.||Sterna acuticauda||Blackbellied tern|
|111.||Sterna albifrons||Little tern|
|112.||Sterna sendvicensis||Sandwitch tern|
|113.||Columba livia||Blue rock pigeon|
|114.||Streptopelia decaocto||Ring dove|
|115.||Sterptopelia senegalensis||Little brown dove|
|116.||Centropus sinensis||Crown pheasant|
|117.||Ketupa zeylonensis||Brown fish owl|
|118.||Athene brama||Spotted owlet|
|119.||Ceryle rudis||Pied kingfisher|
|120.||Alcedo athis||Common kingfisher|
|121.||Halcyon smyrnensis||Whitebreasted kingfisher|
|122.||Merops orientalis||Green-bee eater|
|123.||Merops persicus||Blue-cheeked bee eater|
|124.||Corcias benghalensis||Indian roller|
|125.||Upupa epops||Common hoopoe|
|126.||Amomanes deserti||Desert lark|
|127.||Calendrella brachydactyla||Great short-toed lark|
|128.||Galerida cristata||Crested lark|
|129.||Riparia diluta||Pale sand martin|
|130.||Hirundo fuligula||Crag/rock martin|
|131.||Hirundo rustica||Barn or common swallow|
|132.||Lanius isabellinus||Rufous tailed or Isabelline shrike|
|133.||Lanus meridionalis||Southern gray shrike|
|134.||Lanius vittatus||Bay backed shrike|
|135.||Dicrurus adsimilis||Black drongo|
|136.||Acridotheres adsimilis||Indian myna|
|139.||Oenanthe albonigra||Hume’s wheatear|
|140.||Saxicoloides fulicata||Indian robin|
|141.||Saxicola caprata||Pied robin chat|
|142.||Oenanthe isabellina||Isabelline wheatear|
|143.||Oenanthe sdeserti||Desert wheatear|
|144.||Corvus splendens||House crow|
|145.||Dendrocitta vagabunda||Tree pie|
|146.||Prinia flaviventris||Yellow bellied prinia|
|147.||Prinia burnesii||Rufous vented prinia|
|148.||Pycnonotus leucogenys||White-cheeked bulbul|
|149.||Pycnonotus cafer||Red-vented bulbul|
|150.||Turdoides caudatus||Common babbler|
|151.||Turdoides earlie||Striated babbler|
|152.||Turdoides striata||Jungle babbler|
|153.||Rhipidura aureola||White browed fantail|
|154.||Phylloscopus collybita||Common chiffchaff|
|155.||Acrocephalous stentoreus||Clamorous reed warbler|
|156.||Sylvia curruca||Lesser whitethroat sylvia|
|157.||Phylloscopus trochiloides||Greenish warbler|
|158.||Motacilla alba||White wagtail|
|159.||Motacilla flava||Yellow wagtail|
|160.||Nectarinia asiatica||Purple sunbird|
|161.||Passer domesticus||House sparrow|
|162.||Passer pyrrhonotus||Sindh jungle sparrow|
Reptiles: Region of Nara Desert is considered rich in herpeto-fauna with 24 reptilian species belonging to three orders and 12 families. Out of the 24-reptilian species, 2 were herbivores, 13 were carnivores and 9 were insectivores. A famous indigenous Vulnerable reptilian species of marsh crocodile (Crocodylus palustris) was also reported from the Nara Canal and its adjacent territories (Figure 2) (Table 3).
Birds: In the region of NDWC, these wetlands are recognized as the major habitats for the variety of rare and endangered migratory birds. In NDWC, 118 bird species belonging to 13 orders and 35 families belonging were reported. Fifty-nine birds were native species while 53 birds were migratory species. The important migratory birds were the marbled teal, Anan angustirostris (Vulnerable-threatened) and the ferruginous duck, Aythya nyroca and the Indian darter, Anhyinga rufa (Near-threatened) (Table 3).
Small mammals: From the habitat of NDWC the small mammal populations belonging to 3 orders and 5 families were also reported. The small mammals included 5 granivores, 2 herbivores and 1 omnivore (Table 3).
Large Mammals: Large Mammals: Twenty-five species of large mammals were reported. From order Carnivora, 10 species included the jungle cat, jackal, small Indian mongoose, gray mongoose, wolf and red fox and from the Order Artiodactyla, the wild boar (Table 3) (Figure 3–6).
3.2. Analysis of physicochemical parameters
The highest air temperature of 45°C was measured in July and the lowest of 20°C was measured in January (Tables 4, 11). The highest and lowest water temperatures were 42 and 17°C, respectively (Table 4). The highest and lowest values (9.3 and 6.9) for pH were measured in November and December, respectively (Tables 11, 12). The highest and lowest values (9120 and 364 mu/Scm) for EC were measured in November and May, respectively (Tables 11, 13). The highest and lowest values (1042 and 214 mg/L) for TDS were measured in March and May, respectively (Tables 7, 13). The highest and lowest values (186 and 0.20 NTU) for turbidity were measured in the months of January – September, respectively (Tables 7, 9). The highest and lowest values (1214 and 6 mg/L) for Ca were measured in January and November, respectively (Tables 8, 10). The highest and lowest values (876 and 12 mg/L) for Mg were measured in March and May, respectively (Tables 8, 13). The highest and lowest values (5536 and 140 mg/L) for hardness were measured in March and May, respectively (Tables 7, 13). The highest and lowest values (71.6 and 2.0 mg/L) for alkalinity were measured in November and September, respectively (Tables 8, 11). The highest and lowest values (3418 and 22 mg/L) for Cl were measured in March and May, respectively (Tables 7, 13). The highest and lowest values (1231 and 21 mg/L) for Na were measured in November and May, respectively (Tables 10, 13). The highest and lowest values (182 and 3 m/L) for K were measured in January and July, respectively (Tables 7, 13). The highest and lowest values (2980 and 38 mg/L) for SO4 were measured in November and May, respectively (Tables 7, 13). The highest and lowest values (3580 and 0.5 mg/L) for HCO3 were measured in November and July (Tables 8, 11) while the value of 0 for HCO was measured in all the months of the study period (Tables 4–13). The highest and lowest values (4.6 and 2.7 mg/L) for BOD were measured in January and July, respectively (Tables 9, 10). The highest and lowest values (6.1 and 3.7 mg/L) for DO were measured in November and July, respectively (Tables 4, 10).
4. Discussion and conclusion
The Nara Desert Wetland Complex (NDWC) encompasses sandy dunes, steep hills and includes low lying flat zones associated with different natural wetlands formed from the seepage of Nara Canal. These different wetlands are the major perennial source of water for the agricultural lands, local communities, wildlife and grazing livestock. NDWC comprises more than 225 seasonal and permanent, small, medium and large-sized lakes/wetlands. The total area of Nara Canal is distributed from Sorah (Sukkur) to Head Jamrao about 108,960 hectares and Nara Canal was declared in 1972 as a Game Reserve area for the protection of wild animals. The NDWC is also recognized as an essential potential Ramsar Site [1, 2, 3, 4, 5]. The different floral habitation distributed in the Nara Desert includes phytoplankton, reed vegetation, herbs, shrubs and trees. The area is ecologically-rich with the faunal biodiversity which includes zooplankton, invertebrates, fishes, amphibians, reptiles, birds, small and large mammals. The NDWC has received high economic, social, floral and faunal habitats, and aquatic biodiversity values because the local communities are directly or indirectly dependent on these natural sustainable resources [1, 2, 3, 4, 7, 29, 35] (Figure 7).
In the area the water quality and recharged by the Nara Canal is mainly sweet and acceptable ranges of TDS between 500 and 800 ppm except hypersaline lakes. The hypersaline water of desert area is mainly observed brackish which have TDS between 10,000 and 28,000 pp. [5, 36].
The climate of the area is mainly arid having high temperatures and late summer rains observed. The seasonal rainfall is varied and is less than 250–300 mm and rainy season usually starts from June to September. Before the monsoon season, the average temperature is exceeding 45°C in the desert region and in the plains of NDWS the average temperature between 30 and 40°C. The wetland complex is recognized of great hydrological values as 98% Nara Canal water is used for agriculture and only 2% water is used for domestic and drinking purposes. The wetland complex of Nara Canal is 361.6 km long and 90–135 m wide. The maximum water depth of wetland complex is 7.5 m. The highest water discharges of Nara Canal are reported in the months of May–July and the minimum water flow in the August [1, 2, 3, 4, 7].
The assessment of physicochemical parameters such as pH and alkalinity revealed that the lake water has mostly remained alkaline during the whole study period except the Nara Canal station due to its input of rain water. The range of hardness was higher in most of the selected lakes of NDWC. The acceptable level of hardness in lake waters is recognized as 200 mg/L by the World Health Organization . The physicochemical parameters of Na and Mg, as well as the EC, TDS concentrations were found to be higher than the WHO standard. The Na is the major solute that can also affect aquatic biodiversity ; Na concentrations during the study period were higher than WHO accepted standard in most of the wetlands in the NDWC. The WHO recommended that the tolerable level of Cl is 250 mg/L . In this study, the various wetlands had higher Cl concentration than the acceptable WHO standard. However, the concentrations of Ca, K, SO4, HCO3, BOD and DO were higher than the acceptable WHO standard in the most of selected wetlands during the study period.
In the study area, quality of water is mainly sweet and acceptable for drinking purposes. The range of Total Dissolved Solids (TDS) reported between 500 and 800 ppm. In the area, there are also few brackish wetlands reported and TDS varies between 10,000 and 28,000 due to recharge of insufficient amount of water. The quality of ground water is mainly dominated by sulfate, chloride, calcium and magnesium ions [16, 38, 39]. The conductivity (or TDS) is major parameter along with pH in recognizing the water quality. The values of both parameters is considered acceptable in freshwater lakes while it is otherwise considered the saline lakes. If the value of turbidity is higher than considering alkaline water while above the WHO standard level of 5 NTU. The value of higher turbidity may be due to discharge of waste materials and agriculture run off. The Nara Canal is originates from the Indus River. The water in the Indus River is generally contaminated carrying organic and inorganic polluted particles load from the upstream due to anthropogenic activities. The Sindh Environmental Protection Agency (SEPA 2002) recorded that the value of BOD in Indus River is exceeds more than 6.5 mg/L, which is also recognized by Global Environmental Monitoring System (GEMS) the water of Indus River is highly polluted. According to microbiological analysis of water by WWF-Pakistan (2007) confirmed that in the two sites the presence of fecal coliform. The availability of Fecal coliform in the water system is considering harmful for the human population consumption which may cause water borne disease. In freshwater bodies the availability of Fecal coliform is an indicator of contamination with the human and animal excreta [5, 7, 36, 38, 40, 41].
The parameters of water were only collected to examine the quality of water for the purpose of drinking. Although, it has also been reported that the more than 100,000 fisherman population who were directly associated with the fishery occupation have suffered a lot in the recent decades. In the wetland complexes the higher amount of inflow of saline effluent has causing in the devastation of the lake [7, 40].
Hunting: In the study area, the hunting for recreation is observed common and uncontrolled. However, the region is protected but there is no effective implementation of the wildlife laws for the wild animals. Due to hunting pressure, this is also leading to imbalance between the predator and prey species.
Foraging of Livestock: The large amount of grazing livestock in the area together with the recent climatic changes is degrading the food chain in the ecosystem dynamics.
Cutting trees: In the study area, the cutting of trees in the adjoining desert region for continuous practice of conversion of lands into agricultural fields which is affecting the wild population.
Developmental activities: In this modern era the human population is increasing in higher rate and habitation, the developmental activities in the region and conversion of land for the purpose of agriculture has been damaging the wild habitat and ultimately increasing stress on the existing wildlife.
Controlled hunting: To control the hunting the check posts should be established for keeping vigilance at important points on uncontrolled hunting. Due to shortage of infrastructure in Sindh Wildlife Department like as transport system and staff failed to stop hunting so that the officials must enhance staff and transport. The Wildlife authorities must consider strengthening of Sindh Wildlife Department in the region.
Ecotourism: The area of Nara Wetland Complex is a best site for promoting ecotourism. For sighting of wildlife and bird watching the watch towers at potential points and other facilities should be developed for promoting community based conservation tourism. The people of local community should be participated and benefited from all this tourism activates. From local community the youth should be trained as a volunteers and co-guides. These health activities will provide the incentives to the local community as a source of income generating activity and an alternative livelihood source.
Promote participatory wildlife management and conservation: For promoting participation in wildlife management and conservation the institutional capacity of community based organizations in the region should be developed.
This research study on “Ecology and Environmental Assessment of Nara Desert Wetland Complex, (NDWC) Khairpur, Sindh-Pakistan” was financially supported by University of Sindh Jamshoro, Sindh- Pakistan.
Conflict of interest
The research study of “Ecology and Environmental Assessment of Nara Desert Wetland Complex, (NDWC) Khairpur, Sindh-Pakistan”; has there is no conflict of interest.
I am very thankful to WWF-Pakistan and Sindh Wildlife Department for their support during the collection of data in the studied areas of NDWC.
Acronyms and Abbreviations
|TDS||total dissolved solids|
|BOD||biological oxygen demand|
|NDWC||Nara Desert wetland complex|
|WHO||World Health Organization|
|WWF||Worldwide Fund for Nature|