Land-Based Resource Characterization & Threats in the MBRS Land-Based Resource Characterization & Threats in the MBRS Melissa Bailey & Paul Campbell Tufts University

Watersheds “an area of land within which all waters flow to a single river system” ---Heathcote 1998 “the specific land area that drains water into a river system or other body of water” ---The World Bank

Features of a Typical Watershed Reef Overland flow Groundwater flow

Sewage Runoff Soil Erosion Fertilizers Excess Nutrients Pesticide Residues Chemical Infiltration Potential Stresses in Watershed

What is the integrated watershed management approach?

Integrated Watershed Management Principles & Practice Watershed water resources Water Users Socioeconomics Watershed Ecosystem Water supply Water demand Action Point Demand- oriented measures Supply- oriented measures Modified from Heathcote, Isobel. (1998). Integrated Watershed Management: Principles and Practice. p. 4.

Why “Transboundary”? Watersheds do not “fit” into political boundaries or jurisdictions Incompatible management of a resource that cannot be molded to our local, regional or national constructs

Why “Transboundary”?

Watershed Delineations Quintana Roo (Mexico) Rio Hondo (Mexico-Belize)

% Land Cover Land Cover TypeQuintana RooRio HondoRio MotaguaChameleconUlua Agriculture2.60%11.30%32.90%74.60%76.10% Broadleaf forest70.50%60.90%41.10%4.50%3.60% Coastal vegetation--0.03%0.01%0.10% Mangrove5.60%0.47%1.90%0.03%- Mixed forest--6.50%2.50%5.90% Needleleaf forest--3.10%10.30%13.00% Scrub/shrub14.80%24.30%9.80%0.05%0.08% Urban0.27%0.24%0.40%2.10%0.14% Water body0.91%0.18%1.20%0.60%0.80% Wetlands4.80%1.40%2.30%5.10%0.26% Savanna0.10%1.20%0.60%-- Sparse or no vegetation0.33%-0.11%-0.02% Other0.09% 0.06%0.21%-

Quintana Roo

Rio Hondo

Themes in Land Cover Forest Covers: –Reduce runoff & stabilize soils –Improve infiltration and filtration of water –Ecological significance: habitat for interior species

Themes in Land Cover Agriculture: –Can be environmentally sound or unsound –Ecological significance: variable-- crop/farm practice

Themes in Land Cover Wetlands & Mangroves: –Buffering of water contaminants and sediments –Reduce flooding –Ecological significance: nursery & breeding grounds

Themes in Land Cover Urban Development: –Can concentrate & act as a sink for pollutants –Can increase flood potential –Increase erosion/sedimentation –Increase fragmentation of habitat

Rio Hondo Mexico portion: –Coastal Aquaculture –Major crops: corn & sugar cane –Cattle Ranching Belize portion: –Sugar cane –Livestock

Quintana Roo, Yucatan Peninsula Most communities surveyed did not have major agricultural production –Cattle Ranching –Small amount of crop farming –Aquaculture

Agricultural Activities & Risk Potential –Overall, qualitative data show that chemical fertilizers (NPK and urea) and pesticides (in particular, Paraquat and 2,4-D) are common. The actually appropriateness and amount of fertilizer and pesticide applied would require a more rigorous survey of agriculture in region. –Need to have more concrete information about what crops and farming practices that are common within each watershed.

Vulnerability Analysis: Sedimentation RUNOFF model Rainfall Slope Soil Porosity Land Cover Modified RUSLE Input Institutional & Socioeconomic Factors With Relative Erosion Potential for a map of Areas of High Environmental Stress

Missing Elements for Sediment Model in the MBRS Updated land cover More specific agriculture information (e.g. type of crops, farm practice)

Next Step Model for the MBRS Composite of potential stressors in each watershed = “maps” areas under most stress and in need of intervention What we need to complete this composite… Opinion on how much each stressor should factor or “count” in the analysis Better data on water quality, streamflow, infrastructure, sanitation