Sediment loss and its causes in Puerto Rico watersheds

Abstract. A major environmental concern in the Commonwealth of Puerto Rico is increased sediment load to water reservoirs, to estuaries and finally to coral reef areas outside the estuaries. Sediment deposition has significantly reduced the storage capacity of reservoirs, and sediments, the associated contaminants and nutrients that are adsorbed, can stress corals and negatively impact reef health. Therefore, it is important to understand local soil erosion and sediment transport processes to better prevent and manage sediment loss. The main objective of this study was to determine the influence of landscape characteristics on sediment loss. We analyzed available precipitation and sediment data collected in Puerto Rico during the past three decades, and information on land use, soil properties and topography. Our partial least squares analysis was not very successful in identifying major factors associated with sediment loss due to the complexity of the study watersheds. However, the main factors causing sediment loss from ridge watersheds in Puerto Rico were mainly caused by interactions of development, heavy rainfall events (especially the hurricanes) and steep mountainous slopes associated with the ridges. These results improve our understanding of sediment loss resulting from changes in land use/cover within a Puerto Rico watershed, and will allow stakeholders to make more informed decisions about future land use planning.

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Sediment loss and its cause in Puerto Rico watersheds

SOIL ◽

10.5194/soil-1-595-2015 ◽

2015 ◽

Vol 1 (2) ◽

pp. 595-602 ◽

Cited By ~ 20

Author(s):

Y. Yuan ◽

Y. Jiang ◽

E. V. Taguas ◽

E. G. Mbonimpa ◽

W. Hu

Keyword(s):

Land Use ◽

Puerto Rico ◽

Land Use Planning ◽

Environmental Concern ◽

Transport Processes ◽

Landscape Characteristics ◽

Leading Role ◽

Local Soil ◽

Sediment Loss ◽

Sediment Data

Abstract. A major environmental concern in the Commonwealth of Puerto Rico is increased sediment load to water reservoirs, to estuaries, and finally to coral reef areas outside the estuaries. Sediment deposition has significantly reduced the storage capacity of reservoirs, and sediments, with their associated contaminants and nutrients that are adsorbed, can stress corals and negatively impact reef health. To prevent and manage sediment loss it is therefore important to understand local soil erosion and sediment transport processes. The main objective of this study was to determine the influence of landscape characteristics on sediment loss. We analyzed available precipitation and sediment data collected in Puerto Rico during the past three decades, as well as information on land use, soil properties, and topography. Our partial least squares analysis was not very successful in identifying major factors associated with sediment loss due to the complexity of the study's watersheds; however, it was found that topography and rainfall factors do not play a leading role. Sediment loss from the ridge watersheds in Puerto Rico was mainly caused by interactions of development, heavy rainfall events (especially hurricanes), and steep mountainous slopes associated with the ridges. These results improve our understanding of sediment loss resulting from changes in land use/cover within a Puerto Rico watershed, and allow stakeholders to make more informed decisions about land use planning.

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Insights, implications and challenges of studying local soil knowledge for sustainable land use: a critical review

Soil Research ◽

10.1071/sr19227 ◽

2020 ◽

Vol 58 (3) ◽

pp. 219 ◽

Cited By ~ 1

Author(s):

Ha T. N. Huynh ◽

Lisa A. Lobry de Bruyn ◽

Brian R. Wilson ◽

Oliver G. G. Knox

Keyword(s):

Land Use ◽

Land Use Planning ◽

Grey Literature ◽

National Policy ◽

Soil Management ◽

Soil Classification ◽

Developed Countries ◽

Research Area ◽

Sustainable Land Use ◽

Local Soil

Local soil knowledge (LSK) has been recognised for its importance in sustainable soil management and agroecosystems. This paper examines peer-reviewed articles and grey literature documents on LSK during 2003–2018. Research continues to be geographically focused on developing countries, but often in collaboration with researchers from developed countries. There were five key research themes: soil classification and agreement between local and scientific soil knowledge (Theme 1), value of LSK for soil management and decision-making (Theme 2), scientific approach to the incorporation of LSK (Theme 3), application of LSK for identification of and solutions to soil problems (Theme 4) and factors influencing soil knowledge development (Theme 5). Although Theme 1 continued to be a prevalent research area, confirming the importance of visible and topsoil characteristics identified by farmers, examining subsurface soil properties has garnered less research. For LSK to be thoroughly documented requires support by a pluralistic scientific assessment and greater incorporation of social science methodologies. An overarching finding from Themes 2–4 was the importance of designing national programs that incorporate LSK derived from local people and other stakeholders (e.g. scientists and policymakers) to conserve soils. Local soil maps, using LSK terminology, could broaden the appeal and use of maps by local stakeholders to support sustainable land-use planning from the field to national policy-making processes. Finally, cultural and political aspects, known to influence LSK, should be given greater consideration in further research to sustain and develop this knowledge (Theme 5).

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Public Choice Theory and the Politics of Urban Containment: Voter-Centred versus Special-Interest Explanations

Environment and Planning C Government and Policy ◽

10.1068/c9804j ◽

2000 ◽

Vol 18 (2) ◽

pp. 145-162 ◽

Cited By ~ 6

Author(s):

Mark Pennington

Keyword(s):

Land Use ◽

Public Choice ◽

Land Use Planning ◽

Choice Theory ◽

Environmental Concern ◽

Planning System ◽

The Political ◽

Public Choice Theory ◽

Urban Containment ◽

British Planning

The policy of urban containment has lain at the heart of British land-use planning for over fifty years. The author examines the political dynamics underlying the commitment to this policy through the lens of public choice theory. The analysis suggests that macroelectoral shifts in favour of environmental protection have provided a push towards restrictive land-use planning and an emphasis on urban containment in recent years. Evidence of a ‘voluntary’ approach to regulation in other areas of environmental concern, however, suggests that the peculiar focus on containment is attributable to the political power exerted by a coalition of special interests and public sector bureaucrats who benefit most from this core of the British planning system.

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ASSESSING SUSTAINABLE DEVELOPMENT GAPS BETWEEN THE STATE AND LOCAL JURISDICTIONS

Journal of Environmental Assessment Policy and Management ◽

10.1142/s1464333210003681 ◽

2010 ◽

Vol 12 (03) ◽

pp. 263-289 ◽

Cited By ~ 1

Author(s):

ZHENGHONG TANG

Keyword(s):

Land Use ◽

Land Use Planning ◽

Environmental Planning ◽

The State ◽

Policy Recommendations ◽

Local Planning ◽

State And Local ◽

Environmental Goals ◽

Major Factors

State mandates and guidelines significantly influence local land use planning; however few studies have been conducted to empirically detect the gaps in sustainable environmental planning between the state and local jurisdictions. This paper analyses the California Governor's Environmental Goals and Policy Report (EGPR) and 116 local comprehensive land use plans to develop a set of measurable indicators to detect gaps in local planning efforts to incorporate state goals and policies. Descriptive results indicate that the local jurisdictions reached approximately half of the state's sustainable environmental planning goals. The major gaps existed in some region-wide, global-wide, long-term, cumulative, and strategically critical environmental elements. Regression results further highlight the major factors that significantly influenced local jurisdictions' environmental planning abilities. Six policy recommendations are provided to reduce these gaps.

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Landscape Characteristics Influence Ranging Behavior of Asian Elephants at the Human-wildlands Interface in Myanmar

10.21203/rs.3.rs-147899/v1 ◽

2021 ◽

Author(s):

Aung Nyein Chan ◽

G. Wittemyer ◽

J. McEvoy ◽

Amirtharaj Christy Williams ◽

N. Cox ◽

...

Keyword(s):

Land Use ◽

Land Use Planning ◽

Spatial Configuration ◽

Dry Season ◽

Natural Vegetation ◽

Density Estimator ◽

Ranging Behavior ◽

Landscape Characteristics ◽

Model Sets ◽

Annual Range

Abstract Context Asian elephant numbers are declining across much of their range, driven largely by serious threats from land use change resulting in habitat loss and fragmentation. Myanmar, holding critical range for the species, is undergoing major developments due to recent sociopolitical changes. To effectively manage and conserve the remaining populations of endangered elephants in the country, it is crucial to understand their ranging behavior.Objectives Our objectives were to (1) quantify dry season range sizes of elephants in Myanmar and assess how they vary with different configurations of agriculture and natural vegetation; and (2) evaluate how percentage of agriculture within dry core range of elephants relates to their daily distance travelled.Methods We estimated dry season, wet season, and annual range sizes with autocorrelated kernel density estimator (AKDE) using a continuous-time movement modeling (ctmm) framework and reported the 95% and 50% AKDE and 95% Minimum Convex Polygon (MCP) range sizes. In a multiple regression framework, we developed candidate model sets to explain the variation in AKDE range sizes during the better sampled dry season when human-elephant interactions are the most likely to occur.Results Elephant dry season ranges were highly variable averaging 792 km2 and 184.2 km2 for the 95% and 50% AKDE home ranges, respectively. We found both the shape and spatial configuration of agriculture and natural vegetation patches within an individual elephant’s home range play a significant role in determining the size of its range. We also found that elephants are moving more (larger energy expenditure) in ranges with higher percentages of agricultural area.Conclusion Our results provide baseline information for advancing future land use planning that takes into account space-use requirements for elephants. Failing to do so may seriously further endangered declining elephant populations in Myanmar and across the species’ range.

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