Distribution of Seagrass Beds Along the Texas Coast Chris Wilson Marine Science Institute.

16
Distribution of Seagrass Beds Along the Texas Coast Chris Wilson Marine Science Institute

Transcript of Distribution of Seagrass Beds Along the Texas Coast Chris Wilson Marine Science Institute.

Page 1: Distribution of Seagrass Beds Along the Texas Coast Chris Wilson Marine Science Institute.

Distribution of Seagrass Beds Along the Texas Coast

Chris WilsonMarine Science Institute

Page 2: Distribution of Seagrass Beds Along the Texas Coast Chris Wilson Marine Science Institute.

Introduction

• Who – UTMSI and TXCEQ

• Goal – Determine the factors controlling seagrass distributions along the TX coast

• How- Use of GIS and Time Series Data

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Study Location

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Data Aquisition

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Light Decreasing with Depth

R2 = 0.9644

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depth (m)

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Light and Seagrass Cover

Avg Bare vs %SI

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Depth and Total Seagrass Cover

Total Cover vs Depth

0.0010.0020.0030.0040.0050.0060.0070.0080.0090.00

100.00

0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50

depth (m)

% c

over

Page 8: Distribution of Seagrass Beds Along the Texas Coast Chris Wilson Marine Science Institute.

Seagrass Cover and Location

• Red = 0% Cover

• Orange < 50% Cover

• Green > 50% Cover

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2003-2004 Decline in Thalassia

%Thalassia Cover Vs Time

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AveT02 avet03 avet03s avet04 avet05 avet05s

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2003-2004 Decline in Seagrass Cover

Total Seagrass Cover Over Time

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Yearly Average Rainfall For Texas

Yearly Precipitation

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Summer Rainfall- Corpus Christi

Total Summer Precip Over Time

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Monthly Rainfall – Corpus Christi

May Precip Over Time

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July Precip Over Time

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June Precip Over Time

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Decline >20% Quadrat Cover

Page 15: Distribution of Seagrass Beds Along the Texas Coast Chris Wilson Marine Science Institute.

Conclusions

• Light and depth affect the distribution of seagrass beds

• More work needs to be focused on seagrass beds between 1 and 1.5m in depth

• Decline in seagrass cover may have been attributed to rainfall, but more data is needed