Hydrogeology and water quality of the Chakari Basin, Afghanistan

Abstract

Delta notation for reporting of isotope data.-Stable isotope data are reported as a ratio relative to the ratio of a standard. For example, 18 O/ 16 O of a sample is compared with 18 O/ 16 O of a standard by the relation: δ 18 O = (Rsample/Rstandard-1) × 1,000, where Rsample = 18 O/ 16 O in the sample, Rstandard = 18 O/ 16 O in the standard, and δ 18 O = relative difference in concentration, in parts per thousand (per mil). Delta 18 O (δ 18 O) is referred to as delta notation and is the value reported by isotopic laboratories for stable isotope analysis. Deuterium, designated as δ 2 H, can be derived by analogy to δ 18 O where the ratio 2 H:H replaces 18 O/ 16 O in Rsample and Rstandard. The standard used for determining δ 18 O and δ 2 H in water used in this report is Vienna standard mean ocean water (VSMOW). If δ 18 O and δ 2 H samples contain more of the heavier isotopes (18 O or 2 H) than the reference material, the samples have positive per mil values and are referred to as heavier than the reference material or as being enriched in the heavier isotope. Conversely, if the samples contain more of the lighter isotopes (16 O or H) than the reference material, the samples have negative per mil values and are referred to as lighter than the reference material or as being depleted in the heavier isotope. For example, a δ 18 O value of-18.15 per mil can be referred to as lighter than VSMOW or depleted in 18 O relative to VSMOW. Place names given in this report are anglicized translations from the Dari language; however, there may not be a universally accepted English language translation for many names. This report attempts to use the most commonly used translation where possible, but the reader is cautioned that other variants of names may be in use.

Review of climate change science, knowledge and impacts on water resources in South Asia. Background Paper 1

“…Groundwater quality in the Kabul Basin varies greatly from one locale to another, with high concentrations of dissolved solids in some areas (Broshears et al 2005). A significant factor aggravating groundwater pollution in this semiarid country is the limited renewal of groundwater due to inadequate recharge and storage capacities (Mack et al 2014). High concentrations of contaminants are maintained with no dilution.…”

Identification and apportionment of groundwater nitrate sources in Chakari Plain (Afghanistan)

“…Intrusive igneous rocks such as peridotite, mafic ring dike and amphibolite in the investigated area are mainly in small areas near the northwestern corner of the study area. Figure 1 provides a hydrogeologic map of the study area (Mack et al, 2014), modified from Bohannon's geologic map (2010), where geologic units were grouped based on similar hydrologic properties. The unconsolidated sediments in the study area were deposited as a result of erosion processes.…”

“…The unconsolidated sediments which consist of sand, gravel, cobble, and silt are considered the main aquifer. The basin-fill aquifer thickness is estimated to be 5 to 95 m. Depths to water level vary from 4 to 42 m below the land surface in 2013 (Mack et al, 2014). The generalized groundwater flow directions are shown in Fig.…”

“…Nutrients (NO3, NO2, NH3 + , and NH4 + ), major ion, stable isotope ratios of nitrate (δ 15 N-NO3̄ and δ 18 O-NO3), water stable isotope ratios (δ 2 H-H2O and δ 18 O-H2O), and trace elements were determined from filtered samples by the USGS National Water Quality Laboratory in Lakewood, Colorado (USA). Detailed information about sampling procedures and analytical analyses was presented by Mack et al (2014). Some field blanks and duplicates were gathered and analyzed as well for quality control purpose.…”

Quality of groundwater resources in Afghanistan

“…,Broshears et al (2005),Mack et al (2010a),Sundem (2014),Frahmand (2011), andMack et al (2014b). For other provinces,Ansari (2014) assessed physico-chemical characteristics and groundwater quality index in Lashkar Gah City in the Helmand Province,Saffi and Eqrar (2016) investigated groundwater contamination due to arsenic in Maidan Wardak and Ghazni provinces, and Sundem (2014) examined groundwater quality in both Kabul and Maimanah provinces.…”