在土地利用系统中的土壤中金属元素的分解和表征
Farid Ul Haq1, Faridullah Faridullah1, Muhammad Irshad1
1Department of Environmental Sciences, COMSATS University Islamabad, Abbottabad Campus, Abbottabad 22060, Pakistan.
Toxics
|February 23, 2024
概括
土地使用显著改变了中部卡拉科拉姆土壤中的金属元素 (ME) 分布. 农业用地显示出 (Zn), (Ni) 和铜 (Cu) 的最高度,其中Zn占主导地位.
科学领域:
- 环境科学 环境科学
- 土壤科学 土壤科学
- 地质化学 地质化学
背景情况:
- 土地利用实践和覆盖面的变化对卡拉科鲁姆中部的土壤施加了巨大的压力.
- 人类活动影响金属元素 (ME) 在各种土壤类型的空间分布.
- 了解ME分布对于评估土壤健康和环境影响至关重要.
研究的目的:
- 为了调查金属元素 (铜,,) 在土壤中的存在和分布,在中央卡拉库拉姆的不同土地用途.
- 确定土地利用对所选中小企业的度和物种化的影响.
- 为了在各种土地利用系统中比较ME度和提取效率.
主要方法:
- 土壤样本从卡拉科鲁姆中部的永久土,牧场,森林和农田中收集.
- 金属元素 (Cu, Zn, Ni) 采用顺序提取方法 (可交换,吸附,有机结合,碳化,沉,残留) 提取.
- 使用适当的分析技术确定了ME度,并比较了提取效率.
主要成果:
- 根据提取方法,ME度有很大的差异,EDTA > HNO3 > KNO3 > NaOH > H2O.
- 在所有提取方法和土地用途中, (Zn) 的度高于 (Ni) 和铜 (Cu).
- 农业用地显示ME度最高,其次是永久土,森林和牧场. 在农业土壤中,Zn,Ni和Cu的总量分别达到712,656和163 mg/kg.
结论:
- 土地利用是控制中央卡拉科拉姆土壤中金属元素的空间分布和度的关键因素.
- 农业实践导致土壤中金属元素,特别是的含量增加.
- 这项研究提供了基础数据,以了解山区生态系统中的金属元素动态,并为全球研究提供了见解.
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