Soil quality response to land-use change for sugarcane expansion in Brazil

Globally, increasing demands for biofuels have intensified the rate of land-use change (LUC) for expansion of bioenergy crops. In Brazil, the world\'s largest sugarcane-ethanol producer, sugarcane area has expanded by 35% (3.2 Mha) in the last decade. Sugarcane expansion has resulted in extensive pastures being subjected to intensive mechanization and large inputs of agrochemicals, which have direct implications on soil quality (SQ). We hypothesized that LUC to support sugarcane expansion leads to overall SQ degradation. To test this hypothesis we conducted a field-study at three sites in the central-southern region, to assess the SQ response to the primary LUC sequence (i.e., native vegetation to pasture to sugarcane) associated to sugarcane expansion in Brazil. At each land use site undisturbed and disturbed soil samples were collected from the 0-10, 10-20 and 20-30 cm depths. Soil chemical and physical attributes were measured through on-farm and laboratory analyses. A dataset of soil biological attributes was also included in this study. Initially, the LUC effects on each individual soil indicator were quantified. Afterward, the LUC effects on overall SQ were assessed using the Soil Management Assessment Framework (SMAF). Furthermore, six SQ indexes (SQI) were developed using approaches with increasing complexity. Our results showed that long-term conversion from native vegetation to extensive pasture led to soil acidification, significant depletion of soil organic carbon (SOC) and macronutrients [especially phosphorus (P)] and severe soil compaction, which creates an unbalanced ratio between water- and air-filled pore space within the soil and increases mechanical resistance to root growth. Conversion from pasture to sugarcane improved soil chemical quality by correcting for acidity and increasing macronutrient levels. Despite those improvements, most of the P added by fertilizer accumulated in less plant-available P forms, confirming the key role of organic P has in providing available P to plants in Brazilian soils. Long-term sugarcane production subsequently led to further SOC depletions. Sugarcane production had slight negative impacts on soil physical attributes compared to pasture land. Although tillage performed for sugarcane planting and replanting alleviates soil compaction, our data suggested that the effects are short-term with persistent, reoccurring soil consolidation that increases erosion risk over time. These soil physical changes, induced by LUC, were detected by quantitative soil physical properties as well as by visual evaluation of soil structure (VESS), an on-farm and user-friendly method for evaluating SQ. The SMAF efficiently detected overall SQ response to LUC and it could be reliably used under Brazilian soil conditions. Furthermore, since all of the SQI values developed in this study were able to rank SQ among land uses. We recommend that simpler and more cost-effective SQI strategies using a small number of carefully chosen soil indicators, such as: pH, P, K, VESS and SOC, and proportional weighting within of each soil sectors (chemical, physical and biological) be used as a protocol for SQ assessments in Brazilian sugarcane areas. The SMAF and SQI scores suggested that long-term conversion from native vegetation to extensive pasture depleted overall SQ, driven by decreases in chemical, physical and biological indicators. In contrast, conversion from pasture to sugarcane had no negative impacts on overall SQ, mainly because chemical improvements offset negative impacts on biological and physical indicators. Therefore, our findings can be used as scientific base by farmers, extension agents and public policy makers to adopt and develop management strategies that sustain and/or improving SQ and the sustainability of sugarcane production in Brazil.

Student notebook of Samuel Dunbar, 1721-1722

This leather-bound volume contains substantial transcriptions copied by Samuel Dunbar from textbooks while he was a student at Harvard in 1721 and 1722. There is a general index to texts at the end of the volume. Dunbar's notebook provides a window into the state of higher education in the eighteenth century and offers a firsthand account of academic life at Harvard College. Notably, he often indicated the number of days spent copying texts into his book.

An abridgment of what I extracted while an undergraduate at Harvard College, 1766-1769

The bound volume contains excerpts copied by Benjamin Wadsworth from books he read as a student at Harvard in the late 1760s. The volume includes almost no personal commentary on the readings. The excerpts are arranged by year of study for the academic years 1766-1769, beginning when Wadsworth was a sophomore. Each entry begins with a title indicating the book title and author for the passage, and there is an alphabetical index at the end of the volume. Wadsworth selected “extracts” from both religious and secular texts including several histories of England, American histories (with a focus on Puritans), the Bible, and in his senior year, “the Koran of Mohammed.” He also read several books on the art of speech and the art of preaching. There are few science texts included, though the final five-page entry is titled, “What I thought fit to note down from Mr. Winthrop’s experimental Lectures” and contains notes both on the content of Professor John Winthrop’s lectures as well as the types of experiments being performed in class. Wadsworth’s commonplace book offers a window on the state of higher education in the eighteenth century and offers a firsthand account of academic life at Harvard College.

A formação superior para o secretariado na perspectiva luso-brasileira

O objetivo deste estudo foi verificar como se constitui a formação tecnológica para o Secretariado no Brasil e em Portugal, identificando as características da educação formal e a oferta de cursos superiores para esse público, compondo uma análise comparativa do panorama dessa formação nos dois países. Com o embasamento em legislações educacionais e para o trabalho e, ainda, em referenciais sobre o ensino superior no âmbito brasileiro e internacional, a pesquisa se constitui como um estudo de caso, associado ao método comparativo. Os resultados apontam para a tendência da formação tecnológica para os secretários, em detrimento aos de longa duração, trazendo como desafios a ambos os países o acompanhamento dos debates e tendências para o ensino superior, a observação e articulação das demandas à preparação de novos profissionais e a identificação das influências nas expectativas e escolhas de carreira da população jovem.

Education pamphlets

A collection of miscellaneous pamphlets.

National education as a 'civics' literacy in a globalized world: The challenges facing education in Singapore

In this paper we discuss the idea of national education in Singapore. National education, broadly speaking, is a civics programme which seeks to instil a sense of place, identity and history in young Singaporeans with a view to developing national pride and commitment. We set this discussion against the backdrop of globalization and the idea of wired communities and argue that any civics programme needs to be more than simply a nationalistic agenda. To do this we have framed national education in Singapore as a civics literacy informed by the idea of multiliteracies. In doing so, we suggest that the pedagogical work of such an approach can help to sustain the nation state of Singapore yet place the civics agenda on a global stage where national education might be seen more appropriately as global education.