...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Arboriculture >Comparison of two sampling methods for estimating urban tree density.
【24h】

Comparison of two sampling methods for estimating urban tree density.

机译：两种估计城市树木密度的采样方法的比较。

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Sampling can be used as a method for urban tree inventory estimation. There are several sampling methods available, and choices for urban tree inventory methods vary according to the place to be studied and the urban tree conditions. This study compared the results of simple and stratified random sampling methods with those of a total district tree census in Piracicaba, Sao Paulo, Brazil. The simple random sampling error was 17%, and the coefficient of variation was 47%. The stratified random sampling errors varied from 19 to 60%, and their coefficients of variation ranged from 32% to 70%, depending on the stratum. The Shannon diversity index was low in the census (3.07), as in the simple random sampling (1.27). The total number of trees and the number of trees per kilometer of sidewalk calculated by the simple random sampling were similar to those obtained by the census. Because the sampling error obtained by stratified random sampling was higher than for that obtained by simple random sampling, the use of stratified random sampling was not advantageous when compared with simple random sampling. Furthermore, the stratified random sampling procedure was more complex..
机译：采样可以用作城市树木清单估算的方法。有几种可用的采样方法，城市树木清查方法的选择会根据要研究的地点和城市树木的状况而有所不同。这项研究将简单分层的随机抽样方法的结果与巴西圣保罗的皮拉西卡巴的区域树普查的结果进行了比较。简单随机抽样误差为17％，变异系数为47％。分层随机抽样误差范围从19％到60％不等，其变异系数范围从32％到70％不等。与简单随机抽样（1.27）一样，普查中的Shannon多样性指数较低（3.07）。通过简单的随机抽样计算出的树木总数和每公里人行道的树木数与人口普查所得的相似。因为通过分层随机抽样获得的抽样误差高于通过简单随机抽样获得的抽样误差，所以与简单随机抽样相比，分层随机抽样的使用没有优势。此外，分层随机抽样程序更加复杂。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号