Aktivno sudjelovanje u školi

U osnovnoj školi ‘Els Pinetons’ sudjelovanje djece, njihovih obitelji i samih učitelja u školskim aktivnostima smatra se ključnim za stvaranje i razvoj jedinstvenog obrazovnog projekta. U srži svega je ideja da organizacija i rukovođenje svim aktivnostima u školi moraju imati horizontalnu strukturu koja je podijeljena među svim sudionicima, koji tako ostvaruju ključnu ulogu u obrazovanju djece

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time, and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space. While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes, vast areas of the tropics remain understudied. In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity, but it remains among the least known forests in America and is often underrepresented in biodiversity databases. To worsen this situation, human-induced modifications may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge, it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

Responses of a Grassland Ecosystem to 17 Years of Free-air CO2 Enrichment

AbstractGrasslands comprise 70% of all agricultural land worldwide, and provide fodder for life-stock and besides being habitats for flora and wildlife, they contain large carbon and nitrogen stocks. Elevated CO2 concentrations usually increase plant growth in the short-term, particularly in well- fertilized and irrigated crops. Furthermore, plant tissue nutrient concentrations decrease and the subsequent increase in the CN ratio is assumed to be a symptom of a “progressive nitrogen limitation” (PNL), which is still under debate since long-term FACE experiments are scarce.The Giessen FACE experiment started in a N-limited, species-rich grassland ecosystem near Giessen, Germany in 1998. The CO2 concentration was enriched (eCO2) +20% above ambient (aCO2) year-round during daylight hours. Biomass was harvested twice: in spring and late summer, sorted into the functional groups grasses, forbs and legumes, and the plant material was analyzed (Inductively Coupled Plasma Mass Spectrometer ICP–MS and MS) for N and other nutrients.Biomass of grasses was increased by elevated CO2 during the whole 17 years (1998-2014) indicating that dominant grasses react quickly to elevated CO2, while biomass of forbs was first smaller under elevated CO2 until 2007, and then became larger at eCO2 from 2008 to 2014.Elemental concentrations (Ca, Mg, S, N) were decreased by elevated CO2 in grasses, forbs and legumes. However, K and Zn concentrations in forbs and Mn in legumes increased under elevated CO2. During the first 11 years (1998-2008), the removed net N pool with the harvested biomass, was identical under elevated and ambient CO2 conditions, revealing increased N use efficiency under elevated CO2. Weather conditions (extreme summers) should also be taken into account to better understand the mechanisms of long-term biomass response.Our preliminary conclusions are (1) the increasing yield response over time does not support PNL in N-limited grassland, (2) co-existing functional plant groups have different response patterns

Investigating the Dynamics of Deglaciation in Coastal Areas of Southeast Greenland

Southeast (SE) Greenland has experienced large glaciological changes over the last two decades. Glacial retreat, acceleration, and thinning have resulted in substantial mass loss. However, despite its significance, relatively little is known about the glacial history of SE Greenland. Reconstructions of glacier behaviour provide valuable context for assessing the magnitude of present-day changes, they can also be used to better-understand the mechanisms that control glacier behaviour. We present 11 new cosmogenic exposure ages from previously uninvestigated coastal areas of SE Greenland. Paired erratic and bedrock samples from low-elevation locations were analysed for 10Be content. Samples were collected from central areas of Køge Bugt and Ikertivaq; consequently, these samples track the retreat of the major, marine terminating outlet glaciers here. Samples from Gerner Ø and Tugtilik were collected from locations away from major outlet glaciers; these samples track the deglaciation of 'passive' margins of the Greenland Ice Sheet (GrIS). Comparing the timing of deglaciation in these areas with different dynamic regimes permits investigation of the relative influence of ice dynamics on deglaciation. Results from 10Be analysis are complicated; understanding their significance requires careful interpretation and consideration of the individual sample settings. The timing of glacier retreat appears to have been largely dependent on the local physiographic setting and glaciological regime. The deglaciation of Køge Bugt occurred broadly contemporaneously with retreat in Sermilik Fjord, 100 km to the northeast. Fjord retreat in Køge Bugt probably occurred in response to climatic amelioration at the start of the Holocene (Hughes et al., 2012). The deglaciation of Ikertivaq occurred marginally later, but likely also in response to early-Holocene climatic warming. The minor difference in timing may be attributable to the specifc geometry of Ikertivaq. The deglaciation of passive areas appears to have occurred later than in the major fjord systems; this suggests that ice dynamic processes were a key driver of deglaciation in SE Greenland. References: Hughes, A. L. C.; Rainsley, E.; Murray, T.; Fogwill, C. J.; Schnabel, C., Xu, S., 2012. Rapid response of Helheim Glacier, southeast Greenland, to early Holocene climate warming. Geology 40, 427-430