Saltwater Incursion into Micro Tidal Wetlands : Case Studies from Matagorda, Texas and Humacao, Puerto Rico /

Bibliographic Details
Main Author: Colón, Ricardo J. (Author)
Other Authors: Feagin, Russell A. (Thesis advisor)
Format: Thesis eBook
Language:English
Published: [College Station, Texas] : [Texas A & M University], [2013]
Subjects:
Online Access:Link to OAK Trust copy

MARC

Tag First Indicator Second Indicator Subfields
LEADER 00000cam a2200000Ki 4500
001 in00003453949
005 20151206092330.0
006 m fo d
007 cr unu||||||||
008 140306s2013 txu obm 000 0 eng d
035 |a (OCoLC)ocn871554904 
035 |a (OCoLC)871554904 
035 |a (TxCM)http://hdl.handle.net/1969.1/151334 
040 |a TXA  |b eng  |e rda  |e pn  |c TXA  |d TXA  |d UtOrBLW 
049 |a TXAM 
099 |a 2013  |a Dissertation  |a 1969.1/151334 
100 1 |a Colón, Ricardo J.,  |e author. 
245 1 0 |a Saltwater Incursion into Micro Tidal Wetlands :  |b Case Studies from Matagorda, Texas and Humacao, Puerto Rico /  |c by Ricardo J. Colón. 
264 1 |a [College Station, Texas] :  |b [Texas A & M University],  |c [2013] 
300 |a 1 online resource. 
336 |a text  |b txt  |2 rdacontent 
337 |a computer  |b c  |2 rdamedia 
338 |a online resource  |b cr  |2 rdacarrier 
347 |a text file  |b PDF  |2 rda 
500 |a "Major Subject: Ecosystem Science and Management." 
500 |a Includes vita. 
502 |b Doctor of Philosophy  |c Texas A & M University  |d 2013  |o http://hdl.handle.net/1969.1/151334 
504 |a Includes bibliographical references. 
516 |a Text (Dissertation) 
520 3 |a Global climate change threatens the survival of microtidal wetlands by altering fundamental hydrological aspects such as precipitation patterns and tidal exchange. The combination of these stressors results in increased flooding period and soil salinity in coastal wetlands. In this study, we combined the use of detailed hydrological measurements (wetland water level and salinity), LIDAR elevation models, and water stable isotopes tracers (δD, δ18O) to study the balance between freshwater and saltwater inputs on two microtidal wetlands: a saltmarsh in Matagorda, Texas and a freshwater-forested wetland in Humacao, Puerto Rico. In Matagorda, Texas, we described the process of connectivity between different hydrologic units (isolated and connected ponds) within the saltmarsh. Pond connectivity only occurred when water levels in major water bodies adjacent to our study site reached a threshold elevation of 0.39 m. Connections events were correlated to rainfall and - to a lesser extent - wind speed and direction. We conclude that connectivity within the saltmarsh is driven by the combined effect of tidal influence and rainfall inputs, factors that will be altered by sea level rise and climate change-related changes in long term weather patterns. In Humacao, Puerto Rico, we gathered a detailed dataset of changes in salinity and water level in a freshwater forested wetland dominated by the endangered salt intolerant species Pterocarpus officinalis. In addition, we studied tree water use and identified important water sources to the wetland using stable isotope tracers. Firstly, we provide evidence that recent hydrological alterations have effectively transformed the system from mostly freshwater, to a saltwater wedge estuary. Salinity inputs travel via a tidal creek channel that allows the progression of a saltwater wedge to the inland parts of the forest. Our results suggest that inland progression of the saltwater wedge is influenced by amplitude of tidal exchange in the middle portions of the tidal creek and by extended dry periods in the headmost part of the tidal creek. Isotope data showed that surface standing water was influenced by tidal water sources during the dry season, although the spatial extent of this influence was constrained to areas of the forest that had been previously deforested. The isotopic content of groundwater samples taken at increasing distances from the tidal creek revealed that - although surface waters are dominated by freshwater inputs (rainfall and runoff) during the wet season - the influence of tidal water sources at soil depths greater than 60 cm persists throughout the year. Nonetheless, isotopic content of Pterocapus officinalis stem water samples suggest that tree water uptake is constrained to very shallow, unsaturated parts of the soil. We conclude from both case studies that the long term vulnerability of microtidal wetlands to climate change is determined by the interaction of increased annual variability of freshwater inputs along with a steady increase in mean sea levels, and aggravated by extreme climatic events. The electronic version of this dissertation is accessible from http://hdl.handle.net/1969.1/151334 
588 |a Description from author supplied metadata (automated record created 2013-12-16 16:49:59). 
650 4 |a Major Ecosystem Science and Management. 
653 |a sea level rise 
653 |a saltmarshes 
653 |a Pterocarpus officinalis 
653 |a stable isotopes 
700 1 |a Feagin, Russell A.,  |e thesis advisor. 
710 2 |a Texas A & M University,  |e degree granting institution. 
856 4 0 |u http://hdl.handle.net/1969.1/151334  |z Link to OAK Trust copy  |t 0 
948 |a cataloged  |b h  |c 2014/3/6  |d o  |e spoltoratski  |f 2:06:33 pm  |g ETD 
994 |a C0  |b TXA 
999 |a MARS 
999 f f |s 60ea11d0-550b-35ba-8e63-5f9150ca679e  |i 2509a963-adc9-35fd-9e37-08b7e906f849  |t 0 
952 f f |a Texas A&M University  |b College Station  |c Electronic Resources  |s www_evans  |d Available Online  |t 0  |e 2013 Dissertation 1969.1/151334  |h Other scheme 
998 f f |a 2013 Dissertation 1969.1/151334  |t 0  |l Available Online