Does climate change matter for freshwater aquaculture in Bangladesh?

Freshwater aquaculture plays an important role in the economy of Bangladesh, providing food, income, livelihoods and export earnings. However, freshwater aquaculture in the Mymensingh area of north-central Bangladesh has been accompanied by recent concerns over climate change. Field survey revealed that different climatic variables including flood, drought, rainfall variation and temperature fluctuation have had adverse effects on pond-fish culture. These climatic variables have detrimental effects on the ecosystem of ponds and thus affect survival, growth and production of fish. Changes in climatic variables have adverse effects on fish reproduction, grow-out operation, parasite infestation and disease occurrence. Considering vulnerability to the effects of climate change on pond-fish culture, we propose adaptation strategies that need to be introduced to cope with the challenges.     

Radionuclides in marine macroalgae from Amchitka and Kiska Islands in the Aleutians: establishing a baseline for future biomonitoring

Levels of radionuclides in seven species of marine brown algae and Ulva were determined to establish a baseline for the Northern Pacific Ocean/Bering Sea (Aleutian Islands). There were differences in levels among algal species and locations (Amchitka Island vs Kiska Island). No values were above the minimum detectable activity (MDA) level for (137)Cs, (129)I, (60)Co, (152)Eu, (90)Sr, and (99)Tc. There were interspecific differences in some radionuclides: Ulva lactuca (=Ulva fenestrata) had the highest levels of (241)Am, Alaria fistulosa had the highest levels of (239,240)Pu, and Fucus distichus (=Fucus gardneri) had the highest levels of (234)U, (235)U, and (238)U. However, levels of all radionuclides were generally low and near the MDA for all isotopes. Although Amchitka Island had higher levels of (239,240)Pu than Kiska, the differences were very small and not significant biologically. The data indicate that algae can be useful bioindicators of actinides because they accumulate them at very low environmental levels, allowing them to provide early warning of any potential seepage of radionuclides into the marine environment. Further, the data indicate that some species (the intertidal Fucus) are better accumulators than others, and these should be used as bioindicators in future monitoring schemes.     

Beyond the environmental Kuznets curve: Do combined impacts of air transport and rail transport matter for environmental sustainability amidst energy use in E7 economies?

Environment, Development and Sustainability - This study is motivated by the United Nations Sustainable Development Goals (UN-SDG-7,8,11,12 and 13) on the need for clean and responsible energy...     

A spatial zero-inflated poisson regression model for oak regeneration

Ecological counts data are often characterized by an excess of zeros and spatial dependence. Excess zeros can occur in regions outside the range of the distribution of a given species. A zero-inflated Poisson regression model is developed, under which the species range is determined by a spatial probit model, including physical variables as covariates. Within that range, species counts are independently drawn from a Poisson distribution whose mean depends on biotic variables. Bayesian inference for this model is illustrated using data on oak seedling counts. Received: May 2004 / Revised: December 2004     

Limits to local adaptation: some impacts of temperature on Nucella emarginata differ among populations,while others do not

Predicting future impacts of temperature change require consideration of multiple impacts of temperature on organisms from different populations. We explored the impacts of temperature on feeding, growth, and mortality of emarginated dogwhelks, Nucella emarginata, from three populations (34.459, ?120.473; 34.435, ?119.930; 34.355, ?119.441) that are separated by a total distance of <100 km. Collections and experiments took place September–December 2012. Populations differed both in the number of mussels consumed at 16 and 20 °C and in the difference in feeding at these temperatures. Despite differences in feeding, increases in whelk mortality with temperature did not differ among populations, and in the 16 °C treatment changes in whelk mass did not differ among populations. These results indicate population-specific responses may differ even among geographically close populations. However, some traits may be more adaptable than others and impacts of a given change may be limited by various constraints (e.g., changes in feeding may accompany changes in metabolic needs). Improving our predictions of climate change impacts will require considering these issues, which may be especially important for marine communities where species differ widely in developmental mode, population connectivity, and other traits which may affect responses to changing temperatures.     

Modified Cave Entrances: Thermal Effect on Body Mass and Resulting Decline of Endangered Indiana Bats (Myotis sodalis)

Entrances to many caves occupied by the endangered Indiana bat ( Myotis sodalis ) have been modified to control human access. We show that modifying cave entrances can degrade the bats' winter habitat, we demonstrate one mechanism by which this damage occurs, and we document a restoration experiment. We compared a large bar population in an unmodified cave with a small, reduced bat population in a cave with warm winter temperatures resulting from an entrance wall that impeded air exchange. In the modified cave, mean winter temperature at the hibernation site was 5.0° C higher than in the unmodified cave, bats entered hibernation at a 5% higher body mass, bats lost 42% more mass and the frequency distribution of late-winter mass was truncated, with no bats weighing less than 5.4 g. The results describe unacceptable extremes for hibernation: subfreezing temperatures and warm temperatures causing mass-loss rates of more than 0.009 g/day. Over a decade following removal of the entrance-constricting wall, the population increased from 2,000 to 13,000 bats. Previous recommendations, based on common-sense observation, to open blocked cave entrances are confirmed by this study. The similar case of Coach Cave, Kentucky, offers the potential for recovery of 100,000 Indiana bats.