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ObjectivesObjectives1.1. Why quantitative data?Why quantitative data?

2.2. Relationship to attributes and Relationship to attributes and indicatorsindicators

3.3. Accuracy and precision of Accuracy and precision of qualitative and quantitative qualitative and quantitative indicatorsindicators

4.4. Selected measurements Selected measurements (overview)(overview)

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Quantitative measurements Quantitative measurements should be made:should be made:

– where it is necessary to where it is necessary to document assessments document assessments

– for direct comparisons with other for direct comparisons with other locationslocations

– where monitoring data are where monitoring data are required to determine trend required to determine trend

Why quantitative data? - page Why quantitative data? - page 1212

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Intended Applications – Intended Applications – page 1page 1

“This technique, in association with quantitative monitoring and inventory information, can be used to provide early warnings of resource problems on upland rangelands”.

However, “this protocol is NOT to be used to … monitor land or determine trend”

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Indicators and Attributes – page Indicators and Attributes – page 1212

““The best approach to designing a The best approach to designing a quantitative monitoring program that quantitative monitoring program that is compatible with this qualitative is compatible with this qualitative assessment protocol is to select the assessment protocol is to select the best quantitative indicators for each best quantitative indicators for each of the three attributes, rather than of the three attributes, rather than selecting an equivalent quantitative selecting an equivalent quantitative indicator for each qualitative indicator for each qualitative indicator”. indicator”.

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Quantitative are Quantitative are more more preciseprecise

Accuracy and PrecisionAccuracy and Precision

Either qualitative OR Either qualitative OR quantitative can be quantitative can be more more accurateaccurate

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Watters, Weltz, and Smith (1996)Watters, Weltz, and Smith (1996)– Standing biomass, basal cover, nearest pern. Standing biomass, basal cover, nearest pern.

plant, and freq. with no rooted plant showed plant, and freq. with no rooted plant showed strong relationships to the strong relationships to the subjective subjective Site Site Stability Rating.Stability Rating.

Lane, Nichols, and Levick (1999)Lane, Nichols, and Levick (1999) – Verified qualitative Soil and Site Stability Verified qualitative Soil and Site Stability

indicators with quantitative data.indicators with quantitative data.– ““range health assessment methodology is a range health assessment methodology is a

significant advance over previous…significant advance over previous…procedures..”procedures..”

Liebig & Doran (1999)Liebig & Doran (1999) – Farmers perceptions of soil quality were Farmers perceptions of soil quality were

closely related to most lab results…useful closely related to most lab results…useful screen for further evaluations.screen for further evaluations.

Qualitative Indicator ResearchQualitative Indicator Research

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Compaction layerCompaction layer

Soil surfaceSoil surface

NOT a compaction layer*NOT a compaction layer*Soil surfaceSoil surface

*Even though it has a *Even though it has a high (quantitative) bulk high (quantitative) bulk densitydensity

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USDA 1997 (NRCS Pasture & USDA 1997 (NRCS Pasture & Range Handbook)Range Handbook)

Elzinga et al. 1998 (Measuring & Elzinga et al. 1998 (Measuring & Monitoring Plant Populations)Monitoring Plant Populations)

Herrick et al. 2005 (Monitoring Herrick et al. 2005 (Monitoring Manual for Grassland, Shrubland Manual for Grassland, Shrubland and Savanna Ecosystems)and Savanna Ecosystems)

Bureau of Land Management. 1996 Bureau of Land Management. 1996 (Sampling Vegetation Attributes) (Sampling Vegetation Attributes)

Resources – page 112Resources – page 112

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