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To conserve precious and fragile biodiversity hotspots, a crucial step is knowing how the fruit eaters are doing. To assist in that, scientists and students at Michigan State University (MSU) have supersized a database to keep track of such animals and birds. Yanacocha Biological Reserve, Quito, Ecuador: One of the many biodiversity hotspots housing species included in the frugivoria database. [Extracted from the article]

This study follows the evolution of a single biology course designed for non-science majors. In its original design, the course used only traditional pedagogical techniques, such as lecture and textbook homework assignments. Over several iterations of the course, the class combined problem-based learning (PBL) and service learning to better support student knowledge. For this study, our goal was for students to learn biology concepts as they engaged in a lake cleanup project within the greater Chicago metropolitan area. Data sources consisted of pretest, posttest, and final exam scores to assess learning. The results suggest the combination of PBL and service learning led to gains in student learning. [ABSTRACT FROM AUTHOR]

One of the major areas of advancement in environmental science is bioremediation. Researchers have been using bacteria, fungi, algae and now macrophytes to remove pollutants from aquatic and terrestrial ecosystems. Here we share the results of a study on the macrophyte uptake of xenoestrogens from an urban river. We found that the invasive curly leaf pond weed (Potamogeton illinoensis) accumulated an average of 66% higher levels of estrogenic compounds and 94% more Bisphenol-A than the native Illinois pondweed (Potamogeton crispus) in an urban river, in the watershed for the greater Chicago, IL area. The invasive species accumulated 76% more estrone, 55% more 17 β-estradiol and 31% more 17 α-ethynylestradiol than the native species. The Nonnative plants were also 72% larger than the native Illinois Pondweed. Managers may consider using invasive species to remove pollutants from ecosystems and restore ecosystem biogeochemistry [ABSTRACT FROM AUTHOR]

Science education is criticized because it often fails to support problem-solving skills in students. Instead, the instructional methods primarily emphasize didactic models that fail to engage students and reveal how the material can be applied to solve real problems. To overcome these limitations, this study asked participants in a general ecology course to operate an advanced environmental instrumentation (GC/MS), collect pollution samples, complete data analysis, develop an environmental assessment, and proffer a remediation plan for a local river during an ill-structured task. Students were then given a novel task to assess their transfer skills. The study specifically examined student attitudes, effectiveness, and outcomes toward the integration of laboratories into a science course. Results found that students rated their level of instrumentation confidence as low, but showed statistically significant differences on transfer task scores. Implications for research are discussed. [ABSTRACT FROM AUTHOR]

We investigated the effects of three elevated atmospheric CO2 levels on a Populus deltoides plantation at Biosphere 2 Laboratory in Oracle Arizona. Stable isotopes of carbon have been used as tracers to separate the carbon present before the CO2 treatments started (old C), from that fixed after CO2 treatments began (new C). Tree growth at elevated [CO2] increased inputs to soil organic matter (SOM) by increasing the production of fine roots and accelerating the rate of root C turnover. However, soil carbon content decreased as [CO2] in the atmosphere increased and inputs of new C were not found in SOM. Consequently, the rates of soil respiration increased by 141% and 176% in the 800 and 1200 μL L−1 plantations, respectively, when compared with ambient [CO2] after 4 years of exposure. However, the increase in decomposition of old SOM (i.e. already present when CO2 treatments began) accounted for 72% and 69% of the increase in soil respiration seen under elevated [CO2]. This resulted in a net loss of soil C at a rate that was between 10 and 20 times faster at elevated [CO2] than at ambient conditions. The inability to retain new and old C in the soil may stem from the lack of stabilization of SOM, allowing for its rapid decomposition by soil heterotrophs. [ABSTRACT FROM AUTHOR]

• Background Elevated levels of atmospheric [CO2] are likely to enhance photosynthesis and plant growth, which, in turn, should result in increased specific and whole-plant respiration rates. However, a large body of literature has shown that specific respiration rates of plant tissues are often reduced when plants are exposed to, or grown at, high [CO2] due to direct effects on enzymes and indirect effects derived from changes in the plant's chemical composition.• Scope Although measurement artefacts may have affected some of the previously reported effects of CO2 on respiration rates, the direction and magnitude for the effects of elevated [CO2] on plant respiration may largely depend on the vertical scale (from enzymes to ecosystems) at which measurements are taken. In this review, the effects of elevated [CO2] from cells to ecosystems are presented within the context of the enzymatic and physiological controls of plant respiration, the role(s) of non-phosphorylating pathways, and possible effects associated with plant size.• Conclusions Contrary to what was previously thought, specific respiration rates are generally not reduced when plants are grown at elevated [CO2]. However, whole ecosystem studies show that canopy respiration does not increase proportionally to increases in biomass in response to elevated [CO2], although a larger proportion of respiration takes place in the root system. Fundamental information is still lacking on how respiration and the processes supported by it are physiologically controlled, thereby preventing sound interpretations of what seem to be species-specific responses of respiration to elevated [CO2]. Therefore the role of plant respiration in augmenting the sink capacity of terrestrial ecosystems is still uncertain. [ABSTRACT FROM AUTHOR]