Muheeb Awawdeh

An Innovative Nitrate Pollution Index and Multivariate Statistical Investigations of Groundwater Chemical Quality of Umm Rijam Aquifer (B4), North Yarmouk River Basin, Jordan

The chemical quality of the groundwater is modified by several factors, such as interaction with solid phases, residence time of groundwater, seepage of polluted river water, mixing of groundwater with pockets of saline water and anthropogenic impacts (Stallord and Edmond, 1983; Dethier, 1988; Faure, 1998; Umar et. al., 2006; Giridharan et al., 2008). Recently, there has been a tendency for groundwater quality deterioration, which has been caused by human activities (Dragon, 2008). The quality of water is of vital importance for humans, since it is directly linked with human welfare (Gupta et al., 2008). Poor water quality adversely affects the plant growth and human health (WHO, 1984; Hem, 1991; Karanth, 1997). Globally, nitrate is among the most common groundwater contaminants (Rajmohan and Elango, 2005). Potential sources of nitrate in groundwater include: fertilizers, septic tank effluent, municipal sewage, animal feedlots, decaying vegetation, and atmospheric deposition (Spalding and Exner, 1993; Wilhelm et al., 1996). In addition to the presence or absence of potential sources, field characteristics such as soil conditions, recharge rates, and depth to groundwater ultimately dictate an aquifer’s vulnerability to nitrate contamination (Enwright and Hudak, 2009). Water quality index (WQI) is defined as a technique of rating that provides the composite influence of individual water quality parameters on the overall quality of water for human consumption (Vasanthavigar et al., 2010). It is an important parameter for demarcating groundwater quality and its suitability for drinking purposes (Mishra and Patel, 2001; Naik and Purohit, 2001; Avvannavar and Shrihari, 2008). There is a wide range of water quality indices that have been developed and used to classify water quality, which can be categorized based on the used variables (Terrado et al. 2010). Based on the considered variables, three classes of WQIs can be recognized:

Integrating morphological characters, molecular markers, and distribution patterns to assess the identity of Blepharis species from Jordan

BackgroundBlepharis constitutes an important part of the vegetation of the Jordanian arid and semi-arid regions, yet whether one or more species of this genus occurs in the Jordanian area is uncertain. We addressed this question by assessing morphological characters and testing Inter-Simple Sequence Repeat (ISSR) markers from three populations of Blepharis: two northern (lower slopes of Kufranjah valley and the Dead Sea region) and one southern (Wadi al Yutm).ResultsShoots from randomly chosen Blepharis plants were harvested from each of the three populations for morphological and molecular analyses. In the northern populations, spikes were lax and bract width was significantly shorter than length of the longest lateral spine compared to the southern population. A multivariate linear discriminant analysis distinguished the northern populations from the southern one by internode length, bract width, longest lateral spine length, and bract width to spine length ratio. The ISSR analysis revealed that 44 markers across eight primers were polymorphic with major allele frequency of 83.6% and an average of 5.5 polymorphic markers per primer. The genetic resemblance among individuals ranged from 0.27 to 0.96. The three Blepharis populations were accordingly clustered into two distinct groups, similar to the analysis of morphological differences and corresponding with the “northern” and “southern” population designations.ConclusionsOur results strongly indicate the occurrence of two discrete Blepharis species in Jordan and reject the hypothesis that the genus is represented by only one species. We propose that the Blepharis species in Jordan are B. attenutata Napper (represented by the northern populations) and B. ciliaris (L.) B. L. Burtt (represented by the southern population). These findings are important for informing and revising floristic work within the region and an updated key has been included in our findings.