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Gottardini E.,Research and Innovation Center | Cristofori A.,Research and Innovation Center | Cristofolini F.,Research and Innovation Center | Nali C.,University of Pisa | And 3 more authors.
Ecological Indicators | Year: 2014

Ozone may cause functional alterations on plants without, before and besides the onset of visible foliar symptoms. While field assessment techniques for foliar symptoms have been developed and applied even at the large-scale, methods to detect functional alterations were mostly used under controlled experiments with little (if any) formalized field test. During a five-month field survey, two populations of Viburnum lantana L. plants growing at sites characterized by different ozone levels (+62.6% at the high-ozone with respect to the low-ozone, in terms of cumulated exposure) and visible foliar ozone symptoms (from negligible to frequent) were examined in Trentino (North Italy). For each site, five haphazardly selected leaves from six randomly selected plants were monitored to evaluate the temporal trend in the chlorophyll content (ChlSPAD) and chlorophyll a (Chl a) fluorescence transient (FT) in relation to the onset and development of foliar injury. The FT variables considered were: basal (F0) and maximal (FM) fluorescence in the dark-adapted state; maximum quantum yield efficiency (F V/FM); J phase; I-P phase; performance index total (PITOT). We investigated (i) whether the physiological indicators are linked to the development of visible ozone injury on native vegetation; (ii) whether they can be an early indicator of ozone effect on a sensitive species before the onset of visible foliar symptoms; and (iii) what is the appropriate sample size for their reliable measurements. Results show that (i) Chl SPAD and FM decreased concurrently with the onset and time development of foliar injury (suggesting a degradation of chlorophyll due to an excess of the total oxidative stress), with a much stronger reduction when the injury becomes widespread (reduction of chlorophyll due to increased necrotic surface). (ii) At the high ozone site visible foliar symptoms were frequent and appeared on plants displaying significant differences in most of the Chl a FT variables even before the onset of symptoms. (iii) Given the reported variability of the ChlSPAD and Chl a FT data, and assuming a randomized sampling design, an acceptable precision level (defined as SE = 10% of the mean estimated value at P = 95%) can be achieved in most cases by sampling four leaves for each V. lantana plant and five plants per site. Under these conditions, the concurrent measurements of Chl a FT variables together with ozone-specific visible foliar symptoms and ChlSPAD can provide a set of valuable diagnostic indicators for the early identification and assessment of ozone effects on native vegetation and - potentially - for the phenotyping of ozone-sensitive individuals. © 2013 Elsevier Ltd.

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.

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.

Considerable attention was received by the proposed "harmonization" process between forest condition monitoring (FCM) and "traditional" national forest inventories (NFIs) networks. While some harmonization has been achieved and documented within the FCM at European level, it is not so for NFIs. Since the two systems may show remarkable differences also at country level, the extent to which a fully harmonized European-scale FCM-NFI system can be achieved is rather uncertain, if ever possible. In contrast, different harmonization perspectives may be considered at national level: (i) harmonization of assessment/ measurement methods, (ii) functional integration of network while keeping them separate, and (iii) full integration of networks. Unfortunately while the cost-benefit balance of this harmonization processes was not clarified, actions were already undertaken that may lead to the disruption of the FCM data series initiated in the 1980s. The conclusion of the process may be ironical: will the current effort in "harmonizing" NFIs and FCM results into the disruption of the European-wide longest and most harmonized time series of forest condition data? © iForest-Biogeosciences and Forestry.

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.

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.

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.

Ferretti M.,TerraData Environmetrics | Cristofolini F.,Research and Innovation Center | Cristofori A.,Research and Innovation Center | Gerosa G.,Catholic University of the Sacred Heart | Gottardini E.,Research and Innovation Center
Journal of Environmental Monitoring | Year: 2012

A rapid, empirical method is described for estimating weekly AOT40 from ozone concentrations measured with passive samplers at forest sites. The method is based on linear regression and was developed after three years of measurements in Trentino (northern Italy). It was tested against an independent set of data from passive sampler sites across Italy. It provides good weekly estimates compared with those measured by conventional monitors (0.85 ≤ R2 ≤ 0.970; 97 ≤ RMSE ≤ 302). Estimates obtained using passive sampling at forest sites are comparable to those obtained by another estimation method based on modelling hourly concentrations (R2 = 0.94; 131 ≤ RMSE ≤ 351). Regression coefficients of passive sampling are similar to those obtained with conventional monitors at forest sites. Testing against an independent dataset generated by passive sampling provided similar results (0.86 ≤ R2 ≤ 0.99; 65 ≤ RMSE ≤ 478). Errors tend to accumulate when weekly AOT40 estimates are summed to obtain the total AOT40 over the May-July period, and the median deviation between the two estimation methods based on passive sampling is 11%. The method proposed does not require any assumptions, complex calculation or modelling technique, and can be useful when other estimation methods are not feasible, either in principle or in practice. However, the method is not useful when estimates of hourly concentrations are of interest. This journal is © 2012 The Royal Society of Chemistry.

Ferretti M.,TerraData Environmetrics
CAB Reviews: Perspectives in Agriculture, Veterinary Science, Nutrition and Natural Resources | Year: 2011

Much of our knowledge about the status of and changes in ecological systems and their response to environmental stresses has originated from ecological monitoring. However, concern exists about the ability of monitoring to provide 'good' data. The value of monitoring is often questioned and monitoring itself is seen as an exercise with little contact with true science. Such concerns are justified given several examples of abuse and misuse of monitoring data and failure in documenting errors and flaws. When data are flawed, even the most sophisticated statistical and modelling technique is useless. As a consequence, there are risks that the environmental policy decisionmaking process may be severely compromised, leading to wrong decisions and additional costs to society. Data quality is therefore essential for decision quality. However, data quality goes beyond the traditional perception of metrological quality, and the process of obtaining 'good' data needs to consider all the steps involved in the monitoring. Ecological monitoring cannot survive outside a rigorous scientific context, and a comprehensive quality assurance framework is necessary to drive the design and the implementation of a monitoring programme. © CAB International 2011.

Gottardini E.,Research and Innovation Center | Cristofori A.,Research and Innovation Center | Cristofolini F.,Research and Innovation Center | Ferretti M.,TerraData environmetrics
Atmospheric Environment | Year: 2010

To evaluate the spatial variability of ozone concentrations, two studies were undertaken in the montane environment of Trentino region, northern Italy, in 2007. In the first study, a 225 km 2 area was considered. Here, a randomized design was used to evaluate the variability of ozone concentration at 1 and 225 km 2 scale. Measurements were carried out by passive samplers between May and June 2007. In a second study, the whole 6207 km 2 area of Trentino was considered. The area is covered by five grid cells of the European Monitoring and Evaluation Programme (EMEP). A systematic 15 × 15 km grid was used to allocate 15 passive samplers over the entire province, resulting into 1-4 samplers for each of the 5 EMEP grid cells (2500 km 2 each) overlapping the study area. Measurements were carried out between June and September 2007. Accuracy of passive samplers was checked by direct comparison with conventional ozone analysers. Significant differences (P = 0.034) were found in ozone concentration among 1 × 1 km quadrates within the 225 km 2 study area, while variability within the 1 × 1 km grid cells (coefficient of variation, CV′ = 0.12) slightly exceed the measurement error (CV′ = 0.08). At larger scales (225, 2500 and 6207 km 2), ozone concentration shows much higher variability (CV′ from 0.18 to 0.28, with peak values at 0.40). Reported differences lead to very different AOT40 estimates even within the same EMEP grid cell. These findings suggest that 1 × 1 km resolution seems appropriate for ozone concentration modelling. On the other hand, significant sub-grid variation may exist at the resolution adopted by the EMEP model. Coupled with the likely variability of other important meteorological, soil and vegetation variables, our findings suggest that ozone risk assessment for vegetation based on large-scale modelled AOT40 and flux needs to be considered with great caution. The evidence reported in this paper asks for more detailed national-scale modelling, and the development of methods to incorporate local scale variations into large-scale models. © 2009 Elsevier Ltd. All rights reserved.

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