Diversity patterns of amphibians in lowland Amazonian forests in southeastern Peru

Biological diversity is threatened worldwide and it is a priority to generate more information that can be used both for understanding ecological processes and determining conservation strategies. For my dissertation, I focused on amphibian diversity patterns in lowland rainforests of southwestern Amazonia to evaluate the importance of habitat heterogeneity in the region. My main purpose was to test the hypothesis that amphibian communities in different forest types differ in species richness, composition, and abundance. I used standardized visual encounter surveys to quantify the species composition and abundance of amphibians at four sites, each containing four forest types (floodplain, terra firme, bamboo, and palm swamp). I used leaf-litter plots to evaluate the effect of soil and leaf-litter characteristics on species richness and abundance of leaf-litter frogs. I intensively sampled at one site and then sampled three other sites (distance among sites varied 3.5–105 km) to evaluate whether the patterns observed at one site were similar elsewhere. I also updated the information on threatened and potentially threatened amphibians in Peru and my study region. I found that no species appears to have experienced population declines in southeastern Peru, suggesting that the region still contains the original species pool. My results support the hypothesis that amphibian communities differ across forest types and that patterns observed at the local scale (one site) are similar at the regional scale (four sites). My data also indicate that there is no correlation between species composition and geographic distance among sites. Instead, an important proportion of the gamma diversity is represented by habitat-related beta diversity. My leaf-litter plot data showed that part of the variation in the leaf-litter community structure is explained by soil and litter characteristics. I found that soil total phosphorus and, to a lesser extent, humidity, leaf-litter mass, and pH is linked to species presence/absence and abundance. My study provides the first standardized, quantitative comparison of amphibian community structure across four major forest types in southwestern Amazonia and highlights the fact that forest types are complementary and necessary for maintaining high species richness in the region.

Diversity Patterns of Amphibians in Lowland Amazonian Forests in Southeastern Peru

Biological diversity is threatened worldwide and it is a priority to generate more information that can be used both for understanding ecological processes and determining conservation strategies. For my dissertation, I focused on amphibian diversity patterns in lowland rainforests of southwestern Amazonia to evaluate the importance of habitat heterogeneity in the region. My main purpose was to test the hypothesis that amphibian communities in different forest types differ in species richness, composition, and abundance. I used standardized visual encounter surveys to quantify the species composition and abundance of amphibians at four sites, each containing four forest types (floodplain, terra firme, bamboo, and palm swamp). I used leaf-litter plots to evaluate the effect of soil and leaf-litter characteristics on species richness and abundance of leaf-litter frogs. I intensively sampled at one site and then sampled three other sites (distance among sites varied 3.5-105 km) to evaluate whether the patterns observed at one site were similar elsewhere. I also updated the information on threatened and potentially threatened amphibians in Peru and my study region. I found that no species appears to have experienced population declines in southeastern Peru, suggesting that the region still contains the original species pool. My results support the hypothesis that amphibian communities differ across forest types and that patterns observed at the local scale (one site) are similar at the regional scale (four sites). My data also indicate that there is no correlation between species composition and geographic distance among sites. Instead, an important proportion of the gamma diversity is represented by habitat-related beta diversity. My leaf-litter plot data showed that part of the variation in the leaf-litter community structure is explained by soil and litter characteristics. I found that soil total phosphorus and, to a lesser extent, humidity, leaf-litter mass, and pH is linked to species presence/absence and abundance. My study provides the first standardized, quantitative comparison of amphibian community structure across four major forest types in southwestern Amazonia and highlights the fact that forest types are complementary and necessary for maintaining high species richness in the region.

Integrated assessment of water conservation practices for sustainable management strategies

Miami-Dade County implemented a series of water conservation programs, which included rebate/exchange incentives to encourage the use of high efficiency aerators (AR), showerheads (SH), toilets (HET) and clothes washers (HEW), to respond to the environmental sustainability issue in urban areas. This study first used panel data analysis of water consumption to evaluate the performance and actual water savings of individual programs. Integrated water demand model has also been developed for incorporating property’s physical characteristics into the water consumption profiles. Life cycle assessment (with emphasis on end-use stage in water system) of water intense appliances was conducted to determine the environmental impacts brought by each practice. Approximately 6 to 10 % of water has been saved in the first and second year of implementation of high efficiency appliances, and with continuing savings in the third and fourth years. Water savings (gallons per household per day) for water efficiency appliances were observed at 28 (11.1%) for SH, 34.7 (13.3%) for HET, and 39.7 (14.5%) for HEW. Furthermore, the estimated contributions of high efficiency appliances for reducing water demand in the integrated water demand model were between 5 and 19% (highest in the AR program). Results indicated that adoption of more than one type of water efficiency appliance could significantly reduce residential water demand. For the sustainable water management strategies, the appropriate water conservation rate was projected to be 1 to 2 million gallons per day (MGD) through 2030. With 2 MGD of water savings, the estimated per capita water use (GPCD) could be reduced from approximately 140 to 122 GPCD. Additional efforts are needed to reduce the water demand to US EPA’s “Water Sense” conservation levels of 70 GPCD by 2030. Life cycle assessment results showed that environmental impacts (water and energy demands and greenhouse gas emissions) from end-use and demand phases are most significant within the water system, particularly due to water heating (73% for clothes washer and 93% for showerhead). Estimations of optimal lifespan for appliances (8 to 21 years) implied that earlier replacement with efficiency models is encouraged in order to minimize the environmental impacts brought by current practice.

The Role of Agriculture and Food Consumption in Tropical Conservation

A growing human population, shifting human dietary habits, and climate change are negatively affecting global ecosystems on a massive scale. Expanding agricultural areas to feed a growing population drives extensive habitat loss, and climate change compounds stresses on both food security and ecosystems. Understanding the negative effects of human diet and climate change on agricultural and natural ecosystems provides a context within which potential technological and behavioral solutions can be proposed to help maximize conservation. The purpose of this research was to (1) examine the potential effects of climate change on the suitability of areas for commercial banana plantations in Latin America in the 2050s and how shifts in growing areas could affect protected areas; (2) test the ability of small unmanned aerial vehicles (UAVs) to map productivity of banana plantations as a potential tool for increasing yields and decreasing future plantation expansions; (3) project the effects on biodiversity of increasing rates of animal product consumption in developing megadiverse countries; and (4) estimate the capacity of global pasture biomass production and Fischer-Tropsch hydrocarbon synthesis (IGCC-FT) processing to meet electricity, gasoline and diesel needs. The results indicate that (1) the overall extent of areas suitable for conventional banana cultivation is predicted to decrease by 19% by 2050 because of a hotter and drier climate, but all current banana exporting countries are predicted to maintain some suitable areas with no effects on protected areas; (2) Spatial patterns of NDVI and ENDVI were significantly positively correlated with several metrics of fruit yield and quality, indicating that UAV systems can be used in banana plantations to map spatial patterns of fruit yield; (3) Livestock production is the single largest driver of habitat loss, and both livestock and feedstock production are increasing in developing biodiverse tropical countries. Reducing global animal product consumption should therefore be at the forefront of strategies aimed at reducing biodiversity loss; (4) Removing livestock from global pasture lands and instead utilizing the biomass production could produce enough energy to meet 100% of the electricity, gasoline, and diesel needs of over 40 countries with extensive grassland ecosystems, primarily in tropical developing countries.

The role of agriculture and food consumption in tropical conservation

A growing human population, shifting human dietary habits, and climate change are negatively affecting global ecosystems on a massive scale. Expanding agricultural areas to feed a growing population drives extensive habitat loss, and climate change compounds stresses on both food security and ecosystems. Understanding the negative effects of human diet and climate change on agricultural and natural ecosystems provides a context within which potential technological and behavioral solutions can be proposed to help maximize conservation. The purpose of this research was to (1) examine the potential effects of climate change on the suitability of areas for commercial banana plantations in Latin America in the 2050s and how shifts in growing areas could affect protected areas; (2) test the ability of small unmanned aerial vehicles (UAVs) to map productivity of banana plantations as a potential tool for increasing yields and decreasing future plantation expansions; (3) project the effects on biodiversity of increasing rates of animal product consumption in developing megadiverse countries; and (4) estimate the capacity of global pasture biomass production and Fischer-Tropsch hydrocarbon synthesis (IGCC-FT) processing to meet electricity, gasoline and diesel needs. The results indicate that (1) the overall extent of areas suitable for conventional banana cultivation is predicted to decrease by 19% by 2050 because of a hotter and drier climate, but all current banana exporting countries are predicted to maintain some suitable areas with no effects on protected areas; (2) Spatial patterns of NDVI and ENDVI were significantly positively correlated with several metrics of fruit yield and quality, indicating that UAV systems can be used in banana plantations to map spatial patterns of fruit yield; (3) Livestock production is the single largest driver of habitat loss, and both livestock and feedstock production are increasing in developing biodiverse tropical countries. Reducing global animal product consumption should therefore be at the forefront of strategies aimed at reducing biodiversity loss; (4) Removing livestock from global pasture lands and instead utilizing the biomass production could produce enough energy to meet 100% of the electricity, gasoline, and diesel needs of over 40 countries with extensive grassland ecosystems, primarily in tropical developing countries.^