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Cristofolini F.,Research and Innovation Center | Cristofori A.,Research and Innovation Center | Gottardini E.,Research and Innovation Center | MacCherini S.,University of Siena | Ferretti M.,TerraData environmetrics
Ecological Indicators | Year: 2011

Biomonitoring by means of the supersensitive cultivar Nicotiana tabacum Bel-W3 is frequently used to obtain information on ozone effects on plants and estimates of ozone exposure. However, most of biomonitoring surveys do not account for other environmental variables (predictors in a statistical model) and their inherent multicollinearity with ozone. We tested the relative role of different predictors (fixed: time and site; random: ozone, temperature and humidity) on height growth and on the development of visible foliar symptoms of N. tabacum Bel-W3 plants. To do this, we investigated a relatively small area (256 km 2), used a random design at every stage of the survey, controlled watering and protected plants from direct solar radiation and wind. QA/QC procedures were adopted at every stage of the investigation. Linear correlation shows that Leaf Injury Index (LII) and height increment (H.I.) positively related to ozone concentration, elevation and temperature, and negatively to relative humidity. All the predictors correlate to each other. However, relationships between response and ozone vary with the site and the monitoring week. The effect of the random factor "ozone" in combination with fixed factors "site" and "time" on the response variables was therefore formally investigated using the ANCOVA model. Besides ozone, the interactions "ozone × site" and "ozone × time" resulted always significant (0.001 < P < 0.05). While the factor "time" emphasize the inherent development of injury and growth through time, the interaction "ozone × site" pointed out the importance of local conditions. When watering, solar radiation, wind and plant characteristics were controlled, the remaining site-specific covariates of interest were temperature (T) and humidity (RH). When T and RH were accounted for by means of partial correlation analysis, no significant relationship was found between ozone and LII. On the other side, O 3 and RH resulted significant for both absolute and relative height increment. In short, LII seemed to be not solely dependent on ozone, T and RH, but showed to integrate their combined effect. On the other side, H.I. seemed to be favoured by high RH and T, and depressed by high ozone. Based on the above results, we recommend caution when handling bioindicator data: if the purpose is to infer ozone concentrations by leaf injury data, results may be affected by a serious bias, as the frequently reported correlations may be partly an artefact due to co-variation between predictors. © 2010 Elsevier Ltd. Source

Ferretti M.,TerraData environmetrics | Fischer R.,Thnen Institute for World Forestry | Moffat A.J.,Japan Forestry and Forest Products Research Institute
Developments in Environmental Science | Year: 2013

Forest monitoring by terrestrial investigation has achieved a number of results in terms of infrastructure, enhanced international cooperation, development of methods, data, data quality, and capability to provide information. In addition, long-term monitoring data are increasingly requested by researchers and modelers. Despite these achievements, forest monitoring programs are facing increasing challenges related to a superimposed reduction in resources and a generalized loss of appeal and enthusiasm by policy and funding agencies. Although forest monitoring is a relatively young discipline, which has already evolved considerably, a further, rapid evolution is necessary. The next generation of monitoring programs should consider (i) identifying a wider range of users for monitoring information; (ii) expanding monitoring potential by means of connections with terrestrial and remotely based inventory, modeling, and research systems; (iii) adapting and further improving quality and coverage of data, information and reporting to fit specialized stakeholders; and (iv) enhanced global cooperation. Long-term commitment and financial support are necessary to secure continuity of operation, data collection, and maintenance of data series. © 2013 Elsevier Ltd. Source

Ferretti M.,TerraData environmetrics
Developments in Environmental Science | Year: 2013

To be useful in a forest and environmental management perspective, monitoring data need to provide conclusive results in terms of forest's status, changes, and their correlates. To be fit for such a use, monitoring data must satisfy a number of requirements. In particular, well-defined objectives, sound statistical design, and known and documented metrological quality are essential for defensible data, results, and information. Together with other sources of error (nonstatistical errors, model errors, definition errors), they need to be considered at the design stage of the monitoring. The value of a comprehensive Quality Assurance (QA) perspective is emphasized in that it forces program managers and designers to consider and provide explicit answers and solutions for each individual step of the monitoring program. © 2013 Elsevier Ltd. Source

The international, multipartner, multiagency nature of the ICP Forests conditioned its design from the beginning, with a number of trade-offs necessary to accommodate specific needs, perspectives, and monitoring " traditions." Reconciling these differences with the program objectives is a major challenge for program managers and stakeholders. In this chapter, basic design concepts and principles of the ICP Forests are described, together with more recent efforts undertaken to respond to that major challenge. Emphasis is placed on fixed-area plot design for both Levels I and II monitoring intensity, as well as the need to maintain data time series. The newly developed Quality Assurance perspective, the enhanced data management system, and the policy for intellectual property, publication, and data distribution are also important elements of the entire monitoring design. © 2013 Elsevier Ltd. Source

Ferretti M.,TerraData environmetrics
Developments in Environmental Science | Year: 2013

Over the past decades, the demand for and interest in harmonized data on the status of forests has changed in nature, increasing and becoming cross-sectoral. Although its history is much more recent than forest inventories, forest monitoring today has a great potential to provide useful data and information. The chapter outlines the development of monitoring needs over the past 40 years, the value of monitoring and its importance for other forms of scientific inquiry, introduces the basic methodological issues, and presents an overview of the major forest monitoring programs. Emphasis is placed on the importance that monitoring be driven by explicit objectives and grounded on solid scientific background. This chapter presents the aims and structure of the book. © 2013 Elsevier Ltd. Source

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