We use a mechanistically based ecosystem simulation model to describe and analyze the spatial and temporal patterns of terrestrial net primary productivity (NPP) in South America. The Terrestrial Ecosystem Model (TEM) is designed to predict major carbon and nitrogen fluxes and pool sizes in terrestrial ecosystems at continental to global scales. Information from intensively studies field sites is used in combination with continental-scale information on climate, soils, and vegetation to estimate NPP in each of 5888 non-wetland, 0.5° latitude °0.5° longitude grid cells in South America, at monthly time steps. Preliminary analyses are presented for the scenario of natural vegetation throughout the continent, as a prelude to evaluating human impacts on terrestrial NPP. The potential annual NPP of South America is estimated to be 12.5 Pg/yr of carbon (26.3 Pg/yr of organic matter) in a non-wetland area of 17.0 ° 106 km2 . More than 50% of this production occurs in the tropical and subtropical evergreen forest region. Six independent model runs, each based on an independently derived set of model parameters, generated mean annual NPP estimates for the tropical evergreen forest region ranging from 900 to 1510 g°m-2 °yr-1 of carbon, with an overall mean of 1170 g°m-2 °yr-1 . Coefficients of variation in estimated annual NPP averaged 20% for any specific location in the evergreen forests, which is probably within the confidence limits of extant NPP measurements. Predicted rates of mean annual NPP in other types of vegetation ranged from 95 g°m-2 °yr-1 in arid shrublands to 930 g°m@ ?yr-1 in savannas, and were within the ranges measured in empirical studies. The spatial distribution of predicted NPP was directly compared with estimates made using the Miami mode of Lieth (1975). Overall, TEM predictions were °10% lower than those of the Miami model, but the two models agreed closely on the spatial patterns of NPP in south America. Unlike previous models, however, TEM estimates NPP monthly, allowing for the evaluation of seasonal phenomena. This is an important step toward integration of ecosystem models with remotely sensed information, global climate models, and atmospheric transport models, all of which are evaluated at comparable spatial and temporal scales. Seasonal patterns of NPP in South America are correlated with moisture availability in most vegetation types, but are strongly influenced by seasonal differences in cloudiness in the tropical evergreen forests. On an annual basis, moisture availability was the factor that was correlated most strongly with annual NPP in South America, but differences were again observed among vegetation types. These results allow for the investigation and analysis of climatic controls over NPP at continental scales, within and among vegetation types, and within years. Further model validation is needed. Nevertheless, the ability to investigate NPP-environment interactions with a high spatial and temporal resolution at continental scales should prove useful if not essential for rigorous analysis of the potential effects of global climate changes on terrestrial ecosystems.

/pdf/potential-net-primary-productivity-in-south-america-2xjja5q7y2.pdf

Potential Net Primary Productivity in South America: Application of a Global Model

Opinions about education programs and practices are offered frequently --by children, parents, teachers, and policymakers. Credible studies of the impact of programs on the performance of children are far less frequent. Researchers use a variety of tools to determine their impact and efficacy, including sample surveys, narrative studies, and exploratory research. However, randomized field trials, which are commonly used in other disciplines, are rarely employed to measure the impact of education practice. Evidence Matters explores the history and current status of research in education and encourages the more frequent use of such trials. Judith Gueron (Manpower Demonstration Research Corporation), discusses the challenges involved in randomized trials and offers practical advice drawn experience. Robert Boruch (Wharton School, University of Pennsylvania), Dorothy de Moya (Campbell Collaboration Secretariat), and Brooke Snyder (University of Pennsylvania) explore the use of randomized field trials in education and other fields. David Cohen, Stephen Raudenbush, and Deborah Loewenberg Ball (all from the University of Michigan) review the history of progress in education over the past forty years and urge increased research on coherent instruction regimes. Maris Vinovskis (University of Michigan) examines the history and role of the U.S. Department of Education in developing rigorous evaluation of federal programs, and suggests a new National Center for Evaluation and Development. Thomas Cook and Monique Renee Payne (both from Northwestern University) take on the claim that randomized field trials are inappropriate in the U.S. education system. Gary Burtless (Brookings Institution) explores the political and professional factors that influence randomized field trials in economic programs, examining possible explanations for their lack of frequent use in education. Carol Weiss (Harvard University) provides a brief history of community studies in the United States and suggests a variety of alternatives to randomization. It is difficult to gauge the impact of various approaches in education. But the authors give a variety of concrete examples to illustrate the feasibility of randomized trials, and the circumstances under which they are appropriate. By offering a variety of suggestions to improve the methods used to evaluate education programs, the contributors to this volume seek to improve education in the United States. Frederick Mosteller is Roger I. Lee Professor in Mathematical Statistics, emeritus, in the department of statistics at Harvard University. Robert Boruch is the University Trustee Chair Professor the graduate school of education and statistics department at the Wharton School, University of Pennsylvania

Evidence matters : randomized trials in education research

A commonly accepted assumption in music education based on the apprenticeship tradition is that teachers deliver their musical expertise using pedagogically relevant methods that will help them to have effective mastery and control over the process of learning. This article decentres the traditional notion of mastery and pedagogy. Rather, it is suggested that, in line with situated learning theories and research on expertise-based learning, garage rock bands and their informal ways of learning can exemplify how to develop knowledge-building communities and musical expertise in formal music education. However, this approach is not intended to question or replace the need for teachers.

https://journals.sagepub.com/doi/pdf/10.1177/0255761406065472

Garage rock bands: a future model for developing musical expertise?

This longitudinal study draws on positive youth development frameworks and ecological models to examine the role of school-, home- and community-based arts participation in students’ academic (e.g., motivation, engagement) and nonacademic (e.g., self-esteem, life satisfaction) outcomes. The study is based on 643 elementary and high school students from 15 schools conducted over the course of 2 academic years. Structural equation modeling showed that beyond sociodemographics, prior achievement, and prior variance in outcome measures, school predictors of academic and nonacademic outcomes were arts engagement and in-school arts participation; home predictors were parent–child arts interaction and home-based arts resources; and community arts predictors were participation in and attendance at arts events and external arts tuition (the latter, a negative effect). Implications for theory, policy, funding, and practice are discussed.

/pdf/the-role-of-arts-participation-in-students-academic-and-fzj74dnvtw.pdf

The Role of Arts Participation in Students' Academic and Nonacademic Outcomes: A Longitudinal Study of School, Home, and Community Factors.

Using a regionally focused national survey of parents with 4–6-month-olds (N = 2, 250), we addressed associations between musical experience and the frequency and content of playing music and singing for infants. The possible mediation of a classical CD distribution to new parents in hospitals was also investigated. Five variables of experience were considered: (1) respondents' recollections of their mother or (2) father singing to them, (3) playing an instrument, (4) singing in a choir, and (5) taking music lessons. Chi-square analyses indicated that musical experience was highly associated with increased frequency of playing and singing. The content of what was played and sung was less uniformly linked, and revealed individual profiles for each mode of formal experience. Differences were found between those who did and those who did not receive the CD. Results support a systems view of the child in the context of families and society, and have implications about indirect effects of music education.

Passing the Cultural Torch: Musical Experience and Musical Parenting of Infants

Music Matters: A New Philosophy of Music Education:

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

John Lychner

Author Tools

Chat about Author

Papers

Music Matters: A New Philosophy of Music Education: