Browsing by Subject "Agriculture, Forestry and Wildlife"

Biodiversity conservation issues are complex and contentious. In this dissertation, I focus on Indian mammal conservation science, management, as well as policy issues that shape these factors. I am particularly interested in, where and which mammals are extinction prone, and what factors promote species persistence in human-dominated landscapes. I examine patterns of extinction, range contraction and current distribution of 25 species of large mammals in India in Chapters 2 and 3. I apply occupancy models to data from a sub-continental scale expert opinion survey. I model species occurrence in relation to ecological and social covariates based on a priori hypotheses about the determinants of mammalian distribution patterns.

I find that all 25 large mammal species are extinction prone. I find time affects extinction, and conservation initiatives of the last four decades have allowed some species to re-colonize some areas. I find protected wildlife reserves are critically important for persistence of species. Many species with much of their habitat outside existing protected areas will require new protected areas to persist. I find that human population density negatively influences survival probability for species, and human cultural tolerance positively affected persistence of species. Most large-bodied animals, habitat specialists, and rare species had higher extinction probabilities. I find that in addition to protected areas, land use, and human population densities, regionally rooted cultural and religious factors have allowed some species to survive. Conservation strategies must integrate all these factors to ensure the survival of India's large mammals in the future.

Conservation efforts to protect wildlife in human-dominated landscapes, often requires relocation of people. This policy has rarely been examined in detail. In Chapter 4, I focus on a reserve in India's Western Ghats of India to assess resettlement experiences of people during and after implementation of a relocation project.

Lastly, the success or failure of conservation policies and management interventions be they for protecting wildlife or addressing needs of local communities, depends substantially on the attitudes of conservation practitioners. In Chapter 5, I examine the attitudes, perspectives and opinions of Indian conservationists towards conservation issues and policies in India.

An increasing number of experimental studies attempt to maximize biomass production of trees in plantations by removing nutrient and water limitations. The results from these studies begin to inform operational managers. We investigated a Populus trichocarpa Torr. x P. deltoides Bartr. & Marsh plantation with a combined irrigation and nutrient supply system designed to optimize biomass production. Sap flux density was measured continuously over four of the six growing season months, supplemented with periodic measurements of leaf gas exchange and water potential. Measurements of tree diameter and height were used to estimate leaf area and biomass production using allometric relations. Sap flux was converted to canopy conductance, and analyzed based on an empirical model to isolate the effects of water limitation. Actual and soil water-unlimited potential CO2 uptakes were estimated using a Canopy Conductance Constrained Carbon Assimilation (4C-A) scheme, which couples actual or potential canopy conductance with vertical gradients of light distribution, leaf-level conductance, maximum Rubisco capacity (Vcmax) and maximum electron transport (Jmax). Net primary production (NPP) was ~0.43 of gross primary production (GPP); when estimated for individual trees, this ratio was independent of tree size. Based on the same ratio, we found that current irrigation reduced growth by ~18 % compare to growth with no water limitation. To achieve this maximum growth, however, would require 70% more water for transpiration, and would reduce water use efficiency by 27 %, from 1.57 to 1.15 g stem wood C kg-1 water. Given the economic and social values of water, plantation managers appear to have optimized water use.