Sampling And Plot Design

The center point of each plot constitutes the primary sampling unit PSU described in section 2.2.5. The area and vegetation data gathered on each plot serve to support and quantify the information associated with each PSU. Parent Publication. The enhanced forest inventory and analysis program - national sampling design and estimation procedures

The design must be analysed in more detail because the landscape contains many objects with different shapes. Sample plots can consider as a point or an area. The choice of a plot is influenced by both the land use category on it and the objects on it. If the plot is considered as a point, it is possible to easily estimate the land use category

1.4 Choosing a sampling frame Three terms can be distinguished sampling frame, sampling design and plot configuration. Sampling frame refers to the set of all possible sample units sampling design refers to the selection of a subset of sample units to represent the population and plot configuration refers to the size, shape and

Sampling Design Plot location. Completely random sampling, in which sample plots are located independently of one another, minimizes bias and satisfies statistical assumptions. However, random sampling is more difficult and time consuming than other samplinamp designs. Systematic grid sampling is probably the easiest

The tri-areal design is a departure from the polyareal plot sampling pps approach Husch and others 1982 originally implemented by FIA in the early 1960s. The pps design is more efcient for sampling timber and esti- mating volume, but xed-radius plots add versatility by preserving informa- tion about the spatial relationships among trees.

obscure aspects of the sampling and estimation system, as well as examples of calculations for most of the common estimators produced by FIA. Keywords Annual inventory, FIA, forest health monitoring, forest inventory, plot design, sampling frame. Acknowledgments The authors extend special thanks to the nine subject-matter specialists who

Instead, we do plot sampling. By measuring trees in small areas of the forest, called sample plots, we can extrapolate the sampled information and get information about the forest as a whole. Learning Objectives By the end of this lesson, you will be able to 1. Establish a plan to systematically sample the stands in your forest 2.

In this lesson, you will implement a theoretical inventory based on a systematic sampling plot design. The goal for this lesson To create a systematic sampling plot design to survey the forest area. 14.5.1. Inventorying the Forest There are several methods to inventory forests, each of them suiting different purposes and conditions.

sampling intensities less than 1 km apart, a single set of nested subplots can be more efficient i.e., using only the center set of subplots. Figure 2 FIA plot design including both Phase 2 and Phase 3 subplots. Optimization of the plot design features attempts to avoid over-sampling one attribute while under-sampling another.

Plot Layout. An FIA plot consists of a cluster of four circular subplots spaced out in a fixed pattern. The plot is designed to provide a sampling frame for all P2 and P3 measurements. Most tree measurements are taken within the subplots. Seedlings, saplings and other vegetation are measured on the microplots. Annular plots are used for tree