Permanent grassland soils can act as a sink for carbon and may therefore positively contribute to climate change mitigation and adaptation. We compared young (5–15 years since latest grassland renewal) with old (>20 years since latest grassland renewal) permanent grassland soils in terms of carbon stock, carbon sequestration, drought tolerance and flood resistance. The research was carried out on marine clay soil at 10 dairy farms with young and old permanent grassland. As hypothesized, the carbon stock was larger in old grassland (62 Mg C ha−1) topsoil (0–10 cm) than in young grassland topsoil (51 Mg C ha−1). The carbon sequestration rate was greater in young (on average 3.0 Mg C ha−1 year−1) compared with old grassland (1.6 Mg C ha−1 year−1) and determined by initial carbon stock. Regarding potential drought tolerance, we found larger soil moisture and soil organic matter (SOM) contents in old compared with young grassland topsoils. As hypothesized, the old grassland soils were more resistant to heavy rainfall as measured by water infiltration rate and macroporosity (at 20 cm depth) in comparison with the young grassland soils. In contrast to our hypothesis we did not find a difference in rooting between young and old permanent grassland, probably due to large variability in root biomass and root tip density. We conclude that old grasslands at dairy farms on clay soil can contribute more to the ecosystem services climate change mitigation and climate change adaptation than young grasslands. This study shows that under real farm conditions on a clay topsoil, carbon stock increases with grassland age and even after 30 years carbon saturation has not been reached. Further study is warranted to determine by how much extending grassland age can contribute to climate change mitigation and adaptation.
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Postdisciplinarity makes claims on ontological, epistemic, and methodological levels, but it is inevitably a personal philosophical stance. This article represents an existentialist approach to the discourse on postdisciplinarity, offering reflective narratives of three academics. Tomas Pernecky discusses creativity, criticality, freedom, and methodological and epistemic pluralism; Ana María Munar reveals her journey of epistemological awakening; and Brian Wheeller underscores the importance of researchers' subjective and emotive voice. Jointly, the authors depict postdisciplinarity as an invitation to conceptual and interpretive eclecticism, critical analysis, and creative problem solving.
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In 1996 innovative, double major teacher education programs for Physics & Mathematics and Physics & Chemistry were initiated at the University of San Carlos in Cebu, Philippines. Both programs require 4 years of study. From the outset the focus was on making a difference in the quality of Science and Mathematics Teacher Education, producing teachers with a good mastery of subject matter and able to teach the subjects in exciting and effective ways in typical Philippine crowded and resource-poor classrooms. The programs recruit top high school graduates using a promotion and scholarship scheme and then expose them to the best science lecturers at the university, and create a special learning environment for the duration of their training. Early 2011 a study was conducted to assess long term effects of the programs through a tracer study of the 300 alumni, interviews, and 22classroom visits to observe their teaching. Of the 300 alumni 245 are still teaching of whom 33 abroad (mainly USA) and 212 in the Philippines. Alumni are highly valued by principals of the top schools in Cebu and their students win many local and even national science competitions. Their teaching is competent with lots of interaction and good subject matter mastery, but they are also facing some typical Philippine education problems.
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