选修6 Unit 5 The power of nature-【优化探究】2024高考英语一轮复习高考总复习配套课件（人教版 老教材 老高考）

一轮· 英语 1 必备知识 自主梳理 核心考点 互动探究 跟踪检测 巩固提升 课时作业 即时演练 精读真题提素养/主题下的高考拓展运用 (2019·浙江卷) California has lost half its big trees since the 1930s，according to a study to be published Tuesday and climate change seems to be a major factor (因素)． 一轮· 英语 1 必备知识 自主梳理 核心考点 互动探究 跟踪检测 巩固提升 课时作业 即时演练 The number of trees larger than two feet across has declined by 50 percent on more than 46,000 square miles of California forests，the new study finds.No area was spared or unaffected，from the foggy northern coast to the Sierra Nevada Mountains to the San Gabriels above Los Angeles.In the Sierra high country，the number of big trees has fallen by more than 55 percent；in parts of southern California the decline was nearly 75 percent. 一轮· 英语 1 必备知识 自主梳理 核心考点 互动探究 跟踪检测 巩固提升 课时作业 即时演练 Many factors contributed to the decline，said Patrick McIntyre，an ecologist who was the lead author of the study.Woodcutters targeted big trees.Housing development pushed into the woods.Aggressive wildfire control has left California forests crowded with small trees that compete with big trees for resources (资源)． 一轮· 英语 1 必备知识 自主梳理 核心考点 互动探究 跟踪检测 巩固提升 课时作业 即时演练 But in comparing a study of California forests done in the 1920s and 1930s with another one between 2001 and 2010，McIntyre and his colleagues documented a widespread death of big trees that was evident even in wildlands protected from woodcutting or development. 一轮· 英语 1 必备知识 自主梳理 核心考点 互动探究 跟踪检测 巩固提升 课时作业 即时演练 The loss of big trees was greatest in areas where trees had suffered the greatest water shortage.The researchers figured out water stress with a computer model that calculated how much water trees were getting in comparison with how much they needed，taking into account such things as rainfall，air temperature，dampness of soil，and the timing of snowmelt (融雪)． 一轮· 英语 1 必备知识 自主梳理 核心考点 互动探究 跟踪检测 巩固提升 课时作业 即时演练 Since the 1930s，McIntyre said，the biggest factors driving up water str