When Tutors Self Tutor: What Preservice Teachers Learn about Themselves, Technology, and Teaching during a Time of Remote Learning

Tutoring has been called “the act of saying to somebody else, ‘Let me help you learn’ ” (Chin, Rabow, & Estrada, 2011, p. 2). Teacher preparation programs regularly encourage college students becoming elementary or secondary school teachers to tutor younger learners as an early school-based field experience. Tutors, acting as teachers, must learn how to provide ideas and information to aid and encourage students to accomplish learning goals. Tutors must also assess the effectiveness of their decisions about when and how to implement different instructional strategies to respond to students’ needs

Future of keeping pet reptiles and amphibians:towards integrating animal welfare, human health and environmental sustainability

The keeping of exotic pets is currently under debate and governments of several countries are increasingly exploring the regulation, or even the banning, of exotic pet keeping. Major concerns are issues of public health and safety, animal welfare and biodiversity conservation. The keeping of reptiles and amphibians in captivity encompasses all the potential issues identified with keeping exotic pets, and many of those relating to traditional domestic pets. Within the context of risks posed by pets in general, the authors argue for the responsible and sustainable keeping of reptile and amphibian pets by private persons, based on scientific evidence and on the authors' own expertise (veterinary medicine, captive husbandry, conservation biology)

Effects of light and temperature on isoprene emission at different leaf developmental stages of eschweilera coriacea in central Amazon

O isopreno emitido pelas plantas corresponde em cerca de um terço das emissões globais de compostos orgânicos voláteis anualmente. A maior fonte de emissão de isopreno para a atmosfera global é a Bacia Amazônica. Este estudo objetivou identificar e quantificar a emissão de isopreno e fotossíntese em diferentes níveis de intensidade de luz e temperatura foliar, em três fases fenológicas (folha madura recente, folha madura tardia e folha senescente) de Eschweilera coriacea (Matamatá verdadeira) - a espécie com maior distribuição na Amazônia central. In situ, as medidas de fotossíntese e emissão de isopreno da folha madura recente apresentaram as maiores taxas em todos os níveis de luz e de temperatura. Adicionalmente, a capacidade de emissão de isopreno (ES) mudou consideravelmente entre as diferentes idades foliares, sugerindo que o envelhecimento reduz a atividade fotossintética e a produção/emissão de isopreno. O algoritmo de Guenther et al. (1999) demonstrou bom ajuste para a emissão de isopreno em diferentes intensidades de luz, entretanto, diferenças na ES entre as idades foliares influenciaram no rendimento quântico estimado pelo modelo. Em relação à temperatura foliar, a estimativa do algoritmo não foi satisfatória para as temperaturas acima de ~40 °C; isto provavelmente ocorreu pelo fato dos dados não apresentarem temperatura ótima até 45 °C. Nossos resultados são consistentes com a hipótese do isopreno ter um papel funcional para proteger as plantas de altas temperaturas e apontam a necessidade de incluir os efeitos da fenologia foliar em modelos de emissão de isopreno

Seasonality of isoprenoid emissions from a primary rainforest in central Amazonia

Made available in DSpace on 2016-02-26T21:28:34Z (GMT). No. of bitstreams: 5 seasonality.pdf: 2064686 bytes, checksum: 1d89ca4421a7302140c8651d944dd4c9 (MD5) license_url: 49 bytes, checksum: 4afdbb8c545fd630ea7db775da747b2f (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license.txt: 120 bytes, checksum: c5ec8a89f6203da160ca192812b3f657 (MD5) Previous issue date: 2015Tropical rainforests are an important source of isoprenoid and other Volatile Organic Compound (VOC) emissions to the atmosphere. The seasonal variation of these compounds is however still poorly understood. In this study, profiles were collected of the vertical profile of mixing ratios of isoprene, total monoterpenes and total sesquiterpenes, within and above the canopy, in a primary rainforest in central Amazonia, using a Proton Transfer Reaction-Mass Spectrometer (PTR-MS). Fluxes of these compounds from the canopy into the atmosphere were estimated from PTR-MS measurements by using an inverse Lagrangian transport model. Measurements were carried out continuously from September 2010 to January 2011, encompassing the dry and wet seasons. Mixing ratios were higher during the dry (isoprene – 2.68 ± 0.9 ppbv, total monoterpenes – 0.67 ± 0.3 ppbv; total sesquiterpenes – 0.09 ± 0.07 ppbv) than the wet season (isoprene – 1.66 ± 0.9 ppbv, total monoterpenes – 0.47 ± 0.2 ppbv; total sesquiterpenes – 0.03 ± 0.02 ppbv) for all compounds. Ambient air temperature and photosynthetically active radiation (PAR) behaved similarly. Daytime isoprene and total monoterpene mixing ratios were highest within the canopy, rather than near the ground or above the canopy. By comparison, daytime total sesquiterpene mixing ratios were highest near the ground. Daytime fluxes varied significantly between seasons for all compounds. The maximums for isoprene (2.53 ± 0.5 μmol m−2 h−1) and total monoterpenes (1.77 ± 0.05 μmol m−2 h−1) were observed in the late dry season, whereas the maximum for total sesquiterpenes was found during the dry-to-wet transition season (0.77 ± 0.1 μmol m−2 h−1). These flux estimates suggest that the canopy is the main source of isoprenoids to the atmosphere for all seasons. However, uncertainties in turbulence parameterization near the ground could affect estimates of fluxes that come from the ground. Leaf phenology seemed to be an important driver of seasonal variation of isoprenoid emissions. Although remote sensing observations of changes in leaf area index were used to estimate leaf phenology, MEGAN 2.1 did not fully capture the behavior of seasonal emissions observed in this study. This could be a result of very local effects on the observed emissions, but also suggest that other parameters need to be better determined in Biogenic Volatile Organic Compound (BVOC) models. Our results support established findings that seasonality of isoprenoids are driven by seasonal changes in light, temperature and leaf phenology. However, they suggest that leaf phenology and its role on isoprenoid production and emission from tropical plant species needs to be better understood in order to develop mechanistic explanations for seasonal variation in emissions. This also may reduce the uncertainties of model estimates associated with the responses to environmental factors. Therefore, this study strongly encourages long-term measurements of isoprenoid emissions, environmental factors and leaf phenology from leaf to ecosystem scale, with the purpose of improving BVOC model approaches that can characterize seasonality of isoprenoid emissions from tropical rainforests.1

Dry Season Transpiration and Soil Water Dynamics in the Central Amazon.

With current observations and future projections of more intense and frequent droughts in the tropics, understanding the impact that extensive dry periods may have on tree and ecosystem-level transpiration and concurrent carbon uptake has become increasingly important. Here, we investigate paired soil and tree water extraction dynamics in an old-growth upland forest in central Amazonia during the 2018 dry season. Tree water use was assessed via radial patterns of sap flow in eight dominant canopy trees, each a different species with a range in diameter, height, and wood density. Paired multi-sensor soil moisture probes used to quantify volumetric water content dynamics and soil water extraction within the upper 100 cm were installed adjacent to six of those trees. To link depth-specific water extraction patterns to root distribution, fine root biomass was assessed through the soil profile to 235 cm. To scale tree water use to the plot level (stand transpiration), basal area was measured for all trees within a 5 m radius around each soil moisture probe. The sensitivity of tree transpiration to reduced precipitation varied by tree, with some increasing and some decreasing in water use during the dry period. Tree-level water use scaled with sapwood area, from 11 to 190 L per day. Stand level water use, based on multiple plots encompassing sap flow and adjacent trees, varied from ∼1.7 to 3.3 mm per day, increasing linearly with plot basal area. Soil water extraction was dependent on root biomass, which was dense at the surface (i.e., 45% in the upper 5 cm) and declined dramatically with depth. As the dry season progressed and the upper soil dried, soil water extraction shifted to deeper levels and model projections suggest that much of the water used during the month-long dry-down could be extracted from the upper 2-3 m. Results indicate variation in rates of soil water extraction across the research area and, temporally, through the soil profile. These results provide key information on whole-tree contributions to transpiration by canopy trees as water availability changes. In addition, information on simultaneous stand level dynamics of soil water extraction that can inform mechanistic models that project tropical forest response to drought

The green ocean amazon experiment (GOAMAZON2014/5) observes pollution affecting gases, aerosols, clouds, and rainfall over the rain forest

The susceptibility of air quality, weather, terrestrial ecosystems, and climate to human activities was investigated in a tropical environment. © 2017 American Meteorological Society