Scholarlink

<p>The vegetation history of western Mexico during the Holocene has been determined by climate changes and human activities. This study reconstructs these changes through a multiproxy analysis of pollen, diatoms and charcoal from a sedimentary sequence from the La Alberca maar, Guanajuato state, and uses the <i>Alnus</i>/(<i>Alnus</i> + <i>Quercus</i>) ratio (A/A + Q) as an indicator of moisture conditions. The results reveal that from ~ 10,000–6,000&#xa0;cal <span>bp</span> this area had a cool, damp climate, with temperate forests of <i>Pinus</i>, <i>Quercus</i> and <i>Alnus</i>, low fire frequencies, and deep freshwater lakes dominated by benthic diatoms. A significant change in the stratigraphy at 6,000&#xa0;cal <span>bp</span> marked the transition towards aridification with the establishment of dry forests and shrubland , associated with an increase in salinity of water bodies and a high frequency of fires. During the last 4,000&#xa0;years, the climate was arid and variable, and there was intense pre-Hispanic human impact. There were severe drought events, high evaporation and low river flows which affected the ecosystems and are connected with various sociocultural changes in Mesoamerica, resulting in the open landscape that predominates today.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Vegetation history of the Holocene from a maar lake in Guanajuato state, México

  • 期刊论文

  • 发表日期：

    2026年4月7日

查看全文
  • Valerio Castro-López,
  • Gabriela Domínguez-Vázquez,
  • Isabel Israde-Alcántara,
  • Verónica Osuna-Vallejo

摘要

The vegetation history of western Mexico during the Holocene has been determined by climate changes and human activities. This study reconstructs these changes through a multiproxy analysis of pollen, diatoms and charcoal from a sedimentary sequence from the La Alberca maar, Guanajuato state, and uses the Alnus/(Alnus + Quercus) ratio (A/A + Q) as an indicator of moisture conditions. The results reveal that from ~ 10,000–6,000 cal bp this area had a cool, damp climate, with temperate forests of Pinus, Quercus and Alnus, low fire frequencies, and deep freshwater lakes dominated by benthic diatoms. A significant change in the stratigraphy at 6,000 cal bp marked the transition towards aridification with the establishment of dry forests and shrubland , associated with an increase in salinity of water bodies and a high frequency of fires. During the last 4,000 years, the climate was arid and variable, and there was intense pre-Hispanic human impact. There were severe drought events, high evaporation and low river flows which affected the ecosystems and are connected with various sociocultural changes in Mesoamerica, resulting in the open landscape that predominates today.