A study was conducted by collecting eight seepage water samples that drain through the sedimentary rocks, mainly sandstone and shale, to evaluate the hydro- geochemical characteristics. The collected samples were anal...A study was conducted by collecting eight seepage water samples that drain through the sedimentary rocks, mainly sandstone and shale, to evaluate the hydro- geochemical characteristics. The collected samples were analyzed for physico-chemical parameters using standard procedures. Three water types were identified in the Piper plot and the hydrogeochemical evolution starts from a Ca- C1 facies （type 1） via mixed Ca-Mg-C1 and Ca-Na-HCO3 facies （type 2） to Na-C1 facies （type 3）. Increasing trend of electrical conductivity （EC） values were observed from type 1 water to type 3 water. Lower ionic concentrations with an average EC value of 35.7 kts/cm in Ca-C1 facies indicate the recharge water by monsoonal rainfall, and ion exchange/weathering process is reflected in the mixing zone. Higher ionic concentration with an average EC value of 399 kts/cm is noted in Na-C1 facies, which indicates the ion exchange during water-rock interaction. Higher log pCO2 values are also found in this facies, revealing the longer residence time of seepage water in the rock matrix, which release more ions into the water. The relative mobility of elements during weathering suggest that the order of mobility in both sandstone and shale is Na 〉 Ca 〉 Mg 〉 K. It was observed that thehydrogeochemistry of seepage water is mainly controlled by the bedrock geology.展开更多
Allelopathy is one of the most important interactions between plants. Weeds are famous plants from this viewpoint, which can decrease crop production in farms by their allelopathic effects. Research has shown that dif...Allelopathy is one of the most important interactions between plants. Weeds are famous plants from this viewpoint, which can decrease crop production in farms by their allelopathic effects. Research has shown that different plant organs have different allelopathic effects. Redroot pigweed （Amaranthus retroflexus L.） is one of the most common weeds with well-known allelopathic potential. This experiment aimed to study the allelopathic effects of different organs＇ leachate of redroot pigweed on germination and growth of cucumber （Cucumis sativus L.） and wheat （Triticum aestivum L.） as two important crop species. The effect of different organs＇ leachate on seed germination and seedlings growth parameters of tested plants was significantly different. In addition, the effects on cucumber were not the same as wheat. According to the results, wheat plant was more resistant at both seed germination and seedling growth stages in comparison to cucumber. Cucumber only showed normal growth potential when treated with the stem leachate, while wheat showed measurable growth potential in all treatments and leaf leachate showed the highest negative effect on wheat. Accordingly, allelopathic effects of redroot pigweed are dependent not only on leachate concentration and plant species, but also on plant organ from which the leachate was released. Therefore, understanding the altelochemical source （organ） of a donor plant is essential for accurate evaluation ofallelopathic interactions between plants.展开更多
基金University of Malaya for the rock analysis by payment basis through RPI fund
文摘A study was conducted by collecting eight seepage water samples that drain through the sedimentary rocks, mainly sandstone and shale, to evaluate the hydro- geochemical characteristics. The collected samples were analyzed for physico-chemical parameters using standard procedures. Three water types were identified in the Piper plot and the hydrogeochemical evolution starts from a Ca- C1 facies （type 1） via mixed Ca-Mg-C1 and Ca-Na-HCO3 facies （type 2） to Na-C1 facies （type 3）. Increasing trend of electrical conductivity （EC） values were observed from type 1 water to type 3 water. Lower ionic concentrations with an average EC value of 35.7 kts/cm in Ca-C1 facies indicate the recharge water by monsoonal rainfall, and ion exchange/weathering process is reflected in the mixing zone. Higher ionic concentration with an average EC value of 399 kts/cm is noted in Na-C1 facies, which indicates the ion exchange during water-rock interaction. Higher log pCO2 values are also found in this facies, revealing the longer residence time of seepage water in the rock matrix, which release more ions into the water. The relative mobility of elements during weathering suggest that the order of mobility in both sandstone and shale is Na 〉 Ca 〉 Mg 〉 K. It was observed that thehydrogeochemistry of seepage water is mainly controlled by the bedrock geology.
文摘Allelopathy is one of the most important interactions between plants. Weeds are famous plants from this viewpoint, which can decrease crop production in farms by their allelopathic effects. Research has shown that different plant organs have different allelopathic effects. Redroot pigweed （Amaranthus retroflexus L.） is one of the most common weeds with well-known allelopathic potential. This experiment aimed to study the allelopathic effects of different organs＇ leachate of redroot pigweed on germination and growth of cucumber （Cucumis sativus L.） and wheat （Triticum aestivum L.） as two important crop species. The effect of different organs＇ leachate on seed germination and seedlings growth parameters of tested plants was significantly different. In addition, the effects on cucumber were not the same as wheat. According to the results, wheat plant was more resistant at both seed germination and seedling growth stages in comparison to cucumber. Cucumber only showed normal growth potential when treated with the stem leachate, while wheat showed measurable growth potential in all treatments and leaf leachate showed the highest negative effect on wheat. Accordingly, allelopathic effects of redroot pigweed are dependent not only on leachate concentration and plant species, but also on plant organ from which the leachate was released. Therefore, understanding the altelochemical source （organ） of a donor plant is essential for accurate evaluation ofallelopathic interactions between plants.
