2013年环境影响评价技术方法：植物的样方调查和物种重要值

<p style="text-align:center;" class="MsoNormal" align="center"> <span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">2013</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">年环境影响评价技术方法：植物的样方调查和物种重要值</span> </p> <p class="MsoNormal"> <span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">植物的样方调查和物种重要值</span> </p> <p class="MsoNormal"> <span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">自然植被经常需进行现场的样方调查，样方调查中首先须确定样地大小，一般草本的样地在</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">1m2</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">以上，灌木林样地在</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">10m2</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">以上，乔木林样地在</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">100m2</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">以上，样地大小依据植株大小和密度确定。其次须确定样地数目，样地的面积须包括群落的大部分物种，一般可用物种与面积和关系曲线确定样地数目。样地的排列有系统排 列和随机排列两种方式。样方调查中</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">“</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">压线</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">”</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">植物的计量须合理。</span> </p> <p class="MsoNormal"> <span style="font-family:;font-size:16px;"><span style="line-height: 2; font-family: ;" line-height:2;?="" microsoft="" yahei?;?="">在样方调查（主要是进行物种调查、覆盖度调查）的基础上，可依下列方法计算植被中物种的重要值：</span><span style="font-family:SimSun;"><span style="line-height:2;font-family:SimSun;"></span><span style="line-height:2;font-family:SimSun;"></span></span></span> </p> <p class="MsoNormal"> <span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">（1） </span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">密度</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">=</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">个体数目</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">/</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">样地面积；</span> </p> <p style="text-indent:36pt;" class="MsoNormal"> <span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">相对密度</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">=</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">一个种的密度</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">/</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">所有种的密度</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">。</span> </p> <p class="MsoNormal"> <span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">（2） </span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">优势度</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">=</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">底面积（或覆盖面积总值）</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">/</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">样地面积；</span> </p> <p style="text-indent:36pt;" class="MsoNormal"> <span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">相对优势度</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">=</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">一个种的优势度</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">/</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">所有种的优势度</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">。</span> </p> <p class="MsoNormal"> <span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">（3） </span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">频度</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">=</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">包含该种样地数</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">/</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">样地总数；</span> </p> <p style="text-indent:36pt;" class="MsoNormal"> <span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">相对频度</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">=</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">一个种的频度</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">/</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">所有种的频度。</span> </p> <p class="MsoNormal"> <span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">（4） </span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">重要值</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">=</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">相对密度</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">+</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">相对优势度</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">+</span><span style="line-height: 2; font-family: ; font-size: 16px;" line-height:2;?="" microsoft="" yahei?;?="">相对频度。</span> </p>