Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1995. / Includes bibliographical references (p. 227-232). / by Anselm Spoerri. / Ph.D.

Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2000. / Includes bibliographical references (leaves 88-90). / by Benoît Maag. / M.Eng.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1998. / Includes bibliographical references (leaves 164-174). / by Lucio Soibelman. / Ph.D.

Thesis (Sc. D.)--Massachusetts Institute of Technology, Dept. of Civil Engineering, 1991. / Includes bibliographical references (v.2, leaves 589-603). / by Thomas C. Sheahan. / Sc.D.

Thesis (Civ. E.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1996. / Includes bibliographical references (leaves 292-295). / by Darmadi Darmawangsa. / Civ.E.

Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2000. / Includes bibliographical references (leaf 95). / by Marisela Morales. / M.Eng.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2002. / Includes bibliographical references (p. 107-109). / by Nathaniel J. Grier. / S.M.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1994. / Includes bibliographical references (leaves 92-95). / by Andrew Sarosh Altevogt. / M.S.

Thesis (Ph. D. in the Field of Hydrology)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, February 2013. / "February 2012." Cataloged from PDF version of thesis. / Includes bibliographical references (p. 155-172). / This thesis addresses the coupling of hydrologic and biogeochemical processes and, specifically, the organization of ecosystem traits with the water, carbon, and nitrogen cycles. Observations from a factorial irrigation-fertilization experiment in a seasonally dry annual grassland are combined with a simple ecosystem model to identify relationships between vegetation, nitrogen availability, and hydrology. Assuming primary productivity is water-limited, data analysis indicates that soil moisture and canopy conductance are insensitive to nitrogen supply, owing to a trade-off between canopy density and leaf conductance that maximizes efficient use of available water. That is, fertilization-induced increases in leaf area index are offset by reduced leaf area-based stomatal conductance. When primary productivity is assumed to be co-limited by water and nitrogen availability, total surface conductance is estimated to be insensitive to nitrogen supply, but added nitrogen increases the ratio of transpiration to evaporation. This coupled water-carbon-nitrogen model is then extended to predict ecosystem sensitivity across independently varied gradients of water and nitrogen supply rates. This analysis reveals two distinct regimes of plant-resource organization. In arid climates, rooting depths decrease with increasing aridity, while in humid climates, rooting depths increase with aridity. In all climates, rooting depths increase with increased nitrogen supply. Further, relative root-carbon allocation always increases with aridity and decreases with nitrogen supply. These resource use strategies result in an efficient use of available water in arid climates and efficient use of available nitrogen in humid climates. The associated ecosystem process rates indicate that nitrogen supply is an important determinant of surface water and carbon fluxes in humid climates, but only of carbon fluxes in arid climates. / by Anthony Joseph Parolari. / Ph.D.in the Field of Hydrology

Thesis: M. Eng., Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, 2017. / Cataloged from PDF version of thesis. / Includes bibliographical references (pages 105-110). / For over 50 years in The State of Hawai'i, the issues of food self sufficiency and environmental resource protection have been called for, but not necessarily addressed in a quantitative manner. These concerns have been key priorities in The State of Hawai'i Constitution, Hawai'i 2050 Sustainability Plan, Hawai'i County Development Plan and various Community Development Plans. As Hawaiian agriculture transitions from industrial mono-cropping plantation landscapes to small stakeholder farms, it is more important than ever to challenge these issues in the most efficient and sustainable way that is conscious of both environmental resources and resident values. This thesis aims to quantitatively allocate land and environmental resources using a representative entropy-based optimization model, which is formulated to maintain biodiversity while maximizing food self-sufficiency. Rigorous methods to quantify biophysical, water and land resources are implemented to ensure a robust output of optimal cropping areas on a pixel basis. Tradeoff curves are generated comparing fractions of land needed for agricultural expansion, self-sufficient population in fruits and vegetables and total entropy of Hawai'i Island. Results show that Hawai'i Island could sustain up to 6M people in fruits and vegetables, while maintaining the highest spatial heterogeneity and biodiversity. The high populations, however, should be assessed with regard to the cropping land expansions and changes in landscape, as these tradeoffs may outweigh the benefits. / by Jonathan Takao Kaneshiro. / M. Eng.