The impact of urban expansion on the regional environment in Myanmar: a case study of two capital cities

Context

This study examines the spatio-temporal patterns of urban expansion for Yangon and Nay Pyi Taw, the former and new national capitals of Myanmar, and its impact on the regional environment between 2000 and 2013.

Objectives

The objective is to examine different driving forces of urban expansion for Yangon and Nay Pyi Taw, and their environmental consequences during Myanmar’s transitional economy.

Methods

Classified time-series Landsat images are used to evaluate urban expansion processes. Environmental parameters being evaluated in this study include five sets of remotely sensed MODIS land products that are land surface temperature (LST), percent tree cover (PTC), evapotranspiration (ET), terrestrial ecosystem net primary productivity (NPP), and aerosol optical depth (AOD). A time-series trend analysis technique is used to examine the environmental consequences.

Results

The built-up areas in Nay Pyi Taw and Yangon exhibit exponential and polynomial increase, respectively. A 1% increase of built-up area could potentially cause an increase of daytime LST of 0.7 °C, a PTC loss of 2.3%, a decrease in NPP of 34.3 kg/m², and an ET decrease of 42.2 mm for Yangon. Similarly, for Nay Pyi Taw, a 1% increase in built-up area could potentially cause a daytime LST increase of 0.3 °C, a nighttime LST increase of 0.06 °C, a PTC loss of 2.5%, a decrease in NPP of 15.1 kg/m², and a decrease of 19.2 mm ET. No significant change was observed for AOD for either city.

Conclusions

Both cities have experienced extensive urban expansion but with different spatial and temporal characteristics, and their effects on the regional environment are different. Urban expansion of Nay Pyi Taw mainly was government-induced municipal infrastructure development. Yangon’s expansion is mainly caused by population pressure and migration from rural areas. The urban expansion in Yangon was mainly due to reconstruction and renovation, as well as infill development during the study period.

     

Fate of the benzoylphenyl urea CGA-184699 in the cat flea Ctenocephalides felis

HPLC was used to determine levels of the benzoylphenyl urea, CGA-184699, in cat blood, flea faeces and eggs. Rate constants were determined for the decline of CGA-184699 concentration in flea faeces of fleas that fed on both high (696 ng ml^?1) and low (305 ng ml^?1) host blood concentrations. There were strong correlations between the concentration of the drug in the host's blood and in flea eggs, between egg concentration and egg hatch and between the concentration of CGA-184699 in faeces and mortality to larvae feeding upon faeces.     

Habitat functional response mitigates reduced foraging opportunity: implications for animal fitness and space use

Context

Animals selectively use landscapes to meet their energetic needs, and trade-offs in habitat use may depend on availability and environmental conditions. For example, habitat selection at high temperatures may favor thermal cover at the cost of reduced foraging efficiency under consistently warm conditions.

Objective

Our objective was to examine habitat selection and space use in distinct populations of moose (Alces alces). Hypothesizing that endotherm fitness is constrained by heat dissipation efficiency, we predicted that southerly populations would exhibit greater selection for thermal cover and reduced selection for foraging habitat.

Methods

We estimated individual step selection functions with shrinkage for 134 adult female moose in Minnesota, USA, and 64 in Ontario, Canada, to assess habitat selection with variation in temperature, time of day, and habitat availability. We averaged model coefficients within each site to quantify selection strength for habitats differing in forage availability and thermal cover.

Results

Moose in Ontario favored deciduous and mixedwood forest, indicating selection for foraging habitat across both diel and temperature. Habitat selection patterns of moose in Minnesota were more dynamic and indicated time- and temperature-dependent trade-offs between use of foraging habitat and thermal cover.

Conclusions

We detected a scale-dependent functional response in habitat selection driven by the trade-off between selection for foraging habitat and thermal cover. Landscape composition and internal state interact to produce complex patterns of space use, and animals exposed to increasingly high temperatures may mitigate fitness losses from reduced foraging efficiency by increasing selection for foraging habitat in sub-prime foraging landscapes.

     

Disseminated panniculitis in a bottlenose dolphin (Tursiops truncatus) due to Mycobacterium chelonae infection

A 14-year-old female bottlenose dolphin was diagnosed with mycobacterial panniculitis based on punch biopsy specimens. The necropsy revealed numerous pyogranulomas in the blubber, as well as marked acute multifocal necrosuppurative pneumonia and lymphadenitis. In addition, the animal had marked scoliosis, which had first been noted clinically in the dolphin at about 1 mo of age. The animal had been treated with low-dose dexamethasone for approximately the last 19 mo to reduce perceived discomfort from spondyloarthritis and with the progestational agent altrogenest for approximately 8 yr to prevent pregnancy. Acid-fast positive bacilli were detected in the dermis but not in lung or lymph nodes. Mycobacterium chelonae was isolated from pooled skin, lung, and peripheral lymph-node tissue. Mycobacterial infection may be considered as a differential diagnosis in bottlenose dolphins with generalized cutaneous inflammation, particularly if chronic steroid and progesterone treatments were administered, both of which may have an immunomodulatory effect.     

The Effects of Live and Artificial Diets on Feeding Performance of Cultured Winter Flounder,Pseudopleuronectes americanus,in the Wild: Survival,Feeding, Growth,and Nucleic Acid Analyses

This research, which is part of a larger study designed to assess the feasibility of winter flounder, Pseudopleuronectes americanus, stock enhancement in New Hampshire, identifies hatchery feeds that optimize feeding‐related performance of fish once released in the wild. Fish reared on post‐nauplii of brine shrimp, Artemia sp., white worms, Enchytraeus albidus, common burrower amphipods, Leptocheirus plumulosus, and formulated pellets were evaluated post‐release from in situ cages using survival, growth rate, feeding onset and incidence, stomach fullness, diet composition, and nucleic acid‐based condition as indicators of hatchery diet suitability. Amphipod‐reared fish had the highest mean stomach content index of all feed types, including wild fish. Wild and worm‐reared fish exhibited the most similar survival, overall stomach fullness, and diet composition profiles over time. Amphipod‐reared fish ranked highest in overall performance; however, if wild fish performance is viewed as the ideal for a stocked fish, worm‐reared fish performed optimally. This study describes hatchery feeding strategies that may ease the transition of flatfish released into the wild for stock enhancement.