WSP00036

• File Number: 8200.750
• Description: San Juan River General
• State: CO
• Basin: San Juan/Dolores
• Water Division: 7
• Date: 3/1/1975
• Author: BOR
• Title: San Juan Ecology Project - Interim Progress Report - March 1975
• Water Supply Pro - Doc Type: Report/Study

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001571

5. .THE EFFECTS OF WEATH~ MODIFICATION ON THE ALPINE ECOSYSTEM

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5.1

INTRODUCTION

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5.2

THE INFLUENCE OF SNOW AND INCREASED SNOWFALL ON CONTEMPORARY GEOMORPHIC PROCESSES IN ALPINE AREAS
5.2.1 Introduction
5.2.2 Quasi - continuous processes
5.2.2.1 Hypothesis 1
5.2.2.2 Hypothesis 2
5.2.2.3 Quasi - continuous processes: summary
5.2.3 Episodic Processes
5.2.3.1 Snow avalanches
5.2.3.2 Rockfall
5.2.3.3 Mudflows
5.2.3.4 Episodic processes: summary
5.2.4 The Geomorphic Effects of WOSA
5.2.4.1 Quasi - continuous processes
5.2.4.2 Episodic processes
5.2.5 Conclusion

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5.3

PREDICTING SOME EFFECTS OF WEATHER MODIFICATION ON ALPINE VEGETATION

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5.3.1
5.3.2
5.3.3

Proj ec t Design
Phytocoenology and Ordination Studies
Snow Fence Experiments: Primary Production Modeling
5.3.3.1 The function of primary,production in the ecosystem
5.3.3.2 Anticipated effects of snow fences on production
5.3.3.3 Methods
Site selection and plot description
Canopy ,description and biomass estimates
Abiotic measurements
Modeling
5.3.3.4 Results
5.3.3.5 Discussion
Snow Fence Experiments: Decomposition Studies
5.3.4.1 the function of decoIDposition in the ecosystem
5.3.4.2 Anticipated effects of increased snow cover on ,decomposition rates
5.3.4.3 Methods
5.3.4.4 Results and discussion
Williams Lake Basin
Eldorado Lake Basin
Snow Fence effects
Conclusions From This Interim Progress Report
Recommendations For Future Studies

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5.3.5
5.3.6

5.4

THE EFFECTS OF INCREASED SNOWPACK ON THE PHENOLOGY OF SELECTED ALPINE SPECIES
5.4.1 Introduction
5.4.2 History of the Work
5.4.3 Summary of the Results
5.4.3.1 Phenology and physical factors
5.4.3.2 Evaluation of phenological techniques
5.4.3.3 Increased snow accumulation and seed germinability
5.4.3.4 Relevance of this research

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5.5

DENDROCHRONOLOGY AND DENDROECOLOGY
5.5.1 Introduction
5.5.2 Coring Stations
5.5.3 Analysis
5.5.4 Trend Analysis - A Preliminary Evaluation
5.5.4.1 Description of the Trend Method
5.5.4.2 Application of the Trend Method
5.5.5 Climatic Correlation Analysis
5.5.5.1 Data Evaluation
5.5.5.2 Data Analysis
5.5.6 Recommendation

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5.6

ECOLOGICAL OVERVIEW. PART 1. VEGETATION MAPPING
5.6.1 Introduction
5.6.2 Mapping Methodology
5.6.3 Human Influence on Vegetation Cover
5.6.4 Climatic Factors
5.6.5 Successional Factors
5.6.6 Cover Types
5.6.7 Map Products
5.6.8 Areal Distribution of Cover Types - Detailed Maps

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