Contents
xv
Wet Deposition
267
Dry Deposition
268
Cloud Deposition
270
Mass-Balance Techniques
271
Stable Isotope and Other Tracer Techniques
272
Summary and Prospects
273
References
274
18 Landscape and Regional Biogeochemistry: Approaches
277
Ingrid C. Burke
Introduction
277
Pattern Analysis: Design for Field Studies
278
Stratified Sampling and Discrete Units
278
Sampling Continuous Variation
279
Spatially Explicit Analyses
280
Field Analyses
280
Modeling Movement
281
Extrapolating to the Regional or Landscape Scale
282
Field Analysis
282
Modeling
283
Summary
283
References
284
Part 3. Manipulative Ecosystem Experiments
289
19 Nutrient Manipulations in Terrestrial Ecosystems
291
Valerie T. Eviner, F. Stuart Chapin III, and Charles E. Vaughn
Introduction
291
Ecological Questions Addressed by Nutrient Addition
291
Nature of Nutrient Limitation
292
Commonly Limiting Nutrients
293
Single Versus Multiple Nutrient Limitation
293
Experimental Design
293
General Approach
293
Experimental Setup
294
Experimental Design
294
Time Scale of Response
295
Addition Rates
295
How to Add?
295
Form of Nutrients Added
296
Nitrogen
296
Phosphorus
298
Potassium
299
Sulfur
299
Isotopes
300
Alternatives to Nutrient Addition Experiments
302
Summary and Conclusions
303
References
303