The Ancient Agroecology of Perry Mesa

269 Pages·2013·22.1 MB·English

The Ancient Agroecology of Perry Mesa:
Integrating Runoff, Nutrients, and Climate
by
Melissa R. Kruse-Peeples

A Dissertation Presented in Partial Fulfillment
of the Requirements for the Degree
Doctor of Philosophy

Approved April 2013 by the
Graduate Supervisory Committee:

Katherine A. Spielmann, Chair
David R. Abbott
Sharon J. Hall
Keith W. Kintigh

ARIZONA STATE UNIVERSITY
May 2013
ABSTRACT
Understanding agricultural land use requires the integration of natural factors,
such as climate and nutrients, as well as human factors, such as agricultural
intensification. Employing an agroecological framework, I use the Perry Mesa landscape,
located in central Arizona, as a case study to explore the intersection of these factors to
investigate prehistoric agriculture from A.D. 1275-1450. Ancient Perry Mesa farmers
used a runoff agricultural strategy and constructed extensive alignments, or terraces, on
gentle hillslopes to slow and capture nutrient rich surface runoff generated from intense
rainfall. I investigate how the construction of agricultural terraces altered key parameters
(water and nutrients) necessary for successful agriculture in this arid region. Building
upon past work focused on agricultural terraces in general, I gathered empirical data
pertaining to nutrient renewal and water retention from one ancient runoff field. I
developed a long-term model of maize growth and soil nutrient dynamics parameterized
using nutrient analyses of runoff collected from the sample prehistoric field. This model
resulted in an estimate of ideal field use and fallow periods for maintaining long-term soil
fertility under different climatic regimes. The results of the model were integrated with
estimates of prehistoric population distribution and geographical characterizations of the
arable lands to evaluate the places and periods when sufficient arable land was available
for the type of cropping and fallowing systems suggested by the model (given the known
climatic trends and land use requirements). Results indicate that not only do dry climatic
periods put stress on crops due to reduced precipitation but that a reduction in expected
runoff events results in a reduction in the amount of nutrient renewal due to fewer runoff
events. This reduction lengthens estimated fallow cycles, and probably would have
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increased the amount of land necessary to maintain sustainable agricultural production.
While the overall Perry Mesa area was not limited in terms of arable land, this analysis
demonstrates the likely presence of arable land pressures in the immediate vicinity of
some communities. Anthropological understandings of agricultural land use combined
with ecological tools for investigating nutrient dynamics provides a comprehensive
understanding of ancient land use in arid regions.

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ACKNOWLEDGMENTS

I would like to thank the members of my supervisory committee. My committee
offered detailed and insightful guidance throughout the conceptualization of my project
and the final dissertation. I am particularly grateful to Katherine Spielmann, my chair, for
bringing me on as an early member of the Legacies on the Landscape project and
introducing me to Perry Mesa archaeology. The interdisciplinary focus of this project and
the ecological collaborations have greatly shaped my scholarly training. Not only has
Kate provided me professional support, criticism and encouragement throughout my
graduate studies, she has provided me personal support on so many levels; she is a
wonderful mentor. I have thoroughly enjoyed working with Keith Kintigh and David
Abbott. Both have made me question my assumptions and asked poignant questions that
helped improved this project and influenced my thinking.
I am grateful to committee member Sharon Hall for the training and use of her
biogeochemistry laboratory at ASU. I also owe thanks to fellow labmates Jolene Trujillo,
Dana Nakase, Colleen Strawhacker and lab managers David Heuber and Jennifer Lerned
for their support and guidance. Fellow ASU graduate students contributed directly and
indirectly to many of the ideas and approaches to this study, especially Karen
Schollmeyer, Chris Roberts, Colleen Strawhacker, Chris Watkins, Stephanie Kulow,
Scott Ingram and Matthew Peeples. I was also thankful for the field assistance of Rhian
Stotts, Jason Sperinck, and John Hooper. Survey and recording of the sites discussed in
this research would not have been possible without the hard work of the students and
staff of the Legacies on the Landscape field courses through Arizona State University.
I am grateful to Jon Sandor for the use of unpublished data about the nutrient
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content of traditional maize varieties collected by Deb Muenchrath. I benefited greatly
from discussions with Jon and have been greatly inspired by the work of Jon and his
students in the Zuni region.
Funding for this research came from a National Science Foundation Dissertation
Improvement Grant (BCS-1008767), an Arizona State University Graduate and
Professional Students Association Terminal Research Grant, a Research Support Grant
from the ASU School of Human Evolution and Social Change. Additional financial
support came from a Dean’s Advanced Scholarship from the ASU School of Human
Evolution and Social Change, and an associateship through the National Science
Foundation Integrative Graduate Education Research and Training (IGERT) in Urban
Ecology at ASU (DGE-9987612). The NSF Dissertation Improvement Grant provided
funding for an undergraduate research assistant. I am grateful for the assistance from Jake
Lulewicz and the opportunity to train and mentor a student.
I am also grateful to staff of the Bureau of Land Management for supporting this
project, especially Brian Cullpepper, Brian Lausten, Amanda James, Rem Hawes, and
Connie Stone. I am especially grateful to Mike Behrens, fire management officer for the
Phoenix BLM district, for making changes to plans for prescribed burning to allow the
field location to remain undisturbed.
Finally, I want to give a large thank you to my family for their unflagging support
and patience, especially Debbie and Virgil Kruse and Matt Peeples. Matt’s ability to
remain calm and positive kept me going to see the fieldwork, lab work, and writing
through to the end. This dissertation is dedicated to Matt.
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TABLE OF CONTENTS
Page
LIST OF TABLES ................................................................................................................... x
LIST OF FIGURES .............................................................................................................. xiii
CHAPTER
1 INTRODUCTION ............................................................................................... 1
Disseration Objectives .................................................................................... 3
2 AGROECOLOGY, RUNOFF, AGRICULTURAL SYSTEMS, AND
NUTRIENTS ................................................................................................. 7
Runoff Agricultural Systems ........................................................................... 8
Agroecosystem Components ......................................................................... 12
Nutrients ............................................................................................. 12
Nutrient Replinishment Sources ...................................................... 14
3 THE ARCHAEOLOGICAL CASE STUDY: PERRY MESA, CENTRAL
ARIZONA ................................................................................................... 26
Environmental Context ................................................................................. 26
Climte ................................................................................................ 29
Perry Mesa Land Use History ...................................................................... 32
Preclassic Period: A.D. 900-1150 .................................................... 33
Early Classic/Pueblo III Period: A.D. 1150-1275 ........................... 35
Perry Mesa Tradition: A.D. 1275-1450 ........................................... 38
The Perry Mesa Agricultural Landscape ...................................................... 44
Agriculture and Climate Considerations ......................................... 48
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CHAPTER Page
4 CHARACTERISTICS OF THE PERRY MESA RUNOFF
AGROECOSYSTEM ................................................................................ 54
Summary of Previous Studies on Perry Mesa .............................................. 54
Study Location: The Bull Tank Agricultural Area ...................................... 56
Physical and Chemical Characteristics of Terrace and Non-Terrace Soils:
Trench Excavations ....................................................................................... 61
Methods and Procedures ................................................................. 61
Analyses ........................................................................................... 63
Results .............................................................................................. 64
Discussion and Conclusions ............................................................ 74
Linking Soil and Terrace Field Conditoins to Agricultural Productivity .... 78
5 SOIL MOISTURE CONDTIONS OF THE PERRY MESA RUNOFF
AGROECOSYSTEM ................................................................................ 83
Methods and Procedures ............................................................................... 84
Results and Discussion ................................................................................. 90
Terrace Effects on Soil Water Content ........................................... 91
Soil Moisture and Agricultural Planting ....................................... 100
Implications of Summer Planting ................................................. 103
Linking Soil Moisture Conditions to Agricultural Productivity ................ 104
6 SURFACE RUNOFF AND THE PERRY MESA AGROECOSYSTEM .. 107
Environmental Conditions of Surface Runoff ............................................ 107
Methods and Procedures ............................................................................. 108
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CHAPTER Page
Unit Characteristics ....................................................................... 112
Laboratory Analyses ...................................................................... 115
Collection Periods ......................................................................... 118
Results ......................................................................................................... 119
Rainfall Depth and Runoff ............................................................ 119
Nutrient Characteristics of Runoff Discharge .............................. 125
7 SIMULATION MODEL OF LONG-TERM MAIZE GROWTH ............... 128
The Simulation Model of Long-Term Soil Fertility .................................. 129
Variable Parameters .................................................................................... 132
The Nitrogen Cycle ....................................................................... 132
Total Nitrogen (N) and Inorganic Nitrogen (I) Pools in Agricultural
Soils ................................................................................................ 133
Total Nitrogen (r) and Inorganic Nitrogen (rβ) Pools of Runoff
r
Sediments ....................................................................................... 135
Number of Precipitation Events per Precipitation Regime (x) ..... 141
Maize Nitrogen Needs (M) ............................................................ 143
The Models .................................................................................................. 146
Model Results and Discussion .................................................................... 148
Maize Pressures on Soil Fertility .................................................. 148
Runoff Additions to Soil Fertility ................................................. 150
Influence of Climate Regime on Soil Fertility ............................. 154
Conclusions ................................................................................................. 157
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CHAPTER Page
8 CHARACTERIZATION OF THE PREHISTORIC AGRICULTURAL
LANDSCAPE AND LAND USE REQUIREMENTS .......................... 160
Potential Arable Land Estimate .................................................................. 161
Population Estimates ................................................................................... 164
Land Use Estimate ...................................................................................... 171
Climatic Reconstructions .............................................................. 173
Evaluation .................................................................................................... 175
Arable Land Distribution for each Settlement Cluster ................. 175
Arable Land Distribution for the Perry Mesa Region .................. 185
Climatic Context of Arable Land Availability ............................. 188
Conclusions ................................................................................................. 191
Future Directions ........................................................................... 192
Implications for the Study of Agroecology in the Ancient
Southwest ....................................................................................... 192
Implications for the Study of Agroecology for Contemporary Arid
Agriculture ..................................................................................... 194
REFERENCES ................................................................................................................... 197
APPENDIX
A SOIL PROFILE CHARACTERISTICS FROM FIELD EXCAVATION OF
THE BULL TANK AGRICULTURAL FIELD ...................................... 222
B PERMANENT WILTING POINT AND FIELD CAPACITY .................. 227

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APPENDIX Page
C SUPPLEMENTAL RESULTS OF THE RUNOFF COLLECTION
STUDY ...................................................................................................... 231
D RUNOFF COLLECTION DATA ............................................................... 247
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