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The definition of strategies for forest restoration projects depends on information of the successional stage of the area to be restored. Usually, classification of the successional stage is carried out in the field using forest inventory campaigns. However, these campaigns are costly, time-consuming, and limited in terms of spatial coverage. Currently, forest inventories are being improved using 3D data obtained from remote sensing. The objective of this work was to estimate several parameters of interest for the classification of the successional stages of secondary vegetation areas using 3D digital aerial photogrammetry (DAP) data obtained from unmanned aerial vehicles (UAVs). A cost analysis was also carried out considering the costs of equipment and data collection, processing, and analysis. The study was carried out in southeastern Brazil in areas covered by secondary Atlantic Forest. Regression models were fit to estimate total height (h), diameter at breast height (dbh), and basal area (ba) of trees in 40 field inventory plots (0.09 ha each). The models were fit using traditional metrics based on heights derived from DAP and a portable laser scanner (PLS). The prediction models based on DAP data yielded a performance similar to models fit with LiDAR, with values of R² ranging from 88.3% to 94.0% and RMSE between 11.1% and 28.5%. Successional stage maps produced by DAP were compatible with the successional classes estimated in the 40 field plots. The results show that UAV photogrammetry metrics can be used to estimate h, dbh, and ba of secondary vegetation with an accuracy similar to that obtained from LiDAR. In addition to presenting the lowest cost, the estimates derived from DAP allowed for the classification of successional stages in the analyzed secondary forest areas. [ABSTRACT FROM AUTHOR]

Changes in the bioavailability of nitrogen (N) and phosphorus (P) due to biochar have been frequently reported, raising concerns about the management and effectivity of biochar as soil amendment. We investigated the availability of N and P to maize plants cultivated in soil amended with 20 t ha−1 and 30 t ha−1 of biochar from sewage sludge (SSB20, SSB30) and coconut husk (CHB20, CHB30), in a greenhouse experiment. Plant biomass and concentration of N and P in plant tissue and in the rhizosphere and bulk soil were evaluated. All biochar treatments reduced the concentration of NH4+-N by 22–88% in the soil. CHB20, CHB30 and SSB20 increased NO3–N by 17–40% in the bulk soil and reduced it by 21–38% in the rhizosphere, whereas SSB30 increased NO3− -N by 17–25% in both compartments, but decreased plant N and P uptake efficiency. Biochar increased shoot biomass and P availability by 12% and 12–50%, respectively, except the CHB30, which reduced P availability and N and P uptake efficiency. Biochar improved plant growth during the first 60 days of cultivation in the Ultisol, being suitable as soil amendment at lower rate of application. [ABSTRACT FROM AUTHOR]

Copyright of Anuario do Instituto de Geociencias is the property of Universidade Federal do Rio de Janeiro, Instituto de Geociencias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nativa is the property of Revista Nativa and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Anuario do Instituto de Geociencias is the property of Universidade Federal do Rio de Janeiro, Instituto de Geociencias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ciência Florestal (01039954) is the property of Ciencia Florestal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nativa is the property of Revista Nativa and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Geostatistics evaluates the spatial dependence between two or more variables in order to estimate unknown values in space. The objective of this study was to evaluate, using geostatistical techniques, the spatial variability of dendrometric characteristics for a commercial plantation of Eucalyptus grandis x Eucalyptus urophylla located in eastern Minas Gerais, Brazil (19°28' S and 42°49' W). The diameter at breast height (DBH) and commercial height (H) of 60 trees was measured in a forest inventory plot at two, five and seven years old. The volume of each tree in the plot was estimated from allometric equations and values of DBH and H. Spatial dependence of the three dendrometric variables at different ages was evaluated by fitting the experimental semivariogram. Validation of the semivariograms was performed using the jackknife test. The dendrometric variables analyzed presented normal distribution throughout the entire production cycle according to the Kolmogorov-Smirnov test. The spherical model adequately represented the spatial distribution of dendrometric characteristics for the planted forest. The dendrometric characteristics of the analyzed plantation had an average spatial dependence, making the use of geostatistical techniques for characterization of the plantation very important. [ABSTRACT FROM AUTHOR]

Copyright of Revista Caatinga is the property of Revista Caatinga and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• Dry Forest areas would increase 4.3% by assuming the Protected Forest (PF) scenario by 2030 in the Sergipe semiarid region. • Dry Forest areas would decrease 1.8% by assuming the Business as Usual (BAU) scenario by 2030 in the study region. • Carbon sequestration would increase 481.939 Mg between 2017 and 2030 by assuming the PF scenario in the study region. • Carbon sequestration would decrease 736.904 Mg in the BAU between 2017 and 2030 by assuming the BAU scenario in the study region. • Carbon sequestration would increase up to US$ 11.6 million by 2030 by assuming the PF scenario in the study region. The semiarid region in the state of Sergipe, Brazil, approximately 11,000 km2, has experienced high deforestation rates in the last decades, which ultimately contribute to global climatic changes. The valuation of ecosystem services of CO 2 sequestration can support definition of environmental policies to decrease deforestation in that region. This study aimed to assess land use and land cover changes in the Sergipe semiarid region between 1992 and 2017 by applying remotely sensed data and technics; simulate the land use and land cover changes between 2017 and 2030 by applying a cellular automaton model, by assuming current land use trends (Business as Usual – BAU) as a reference scenario, and a more conservative scenario (Protected Forest – PF), in which was assumed an effective enforcement of the Brazilian Forest Code established in 2012; simulate the carbon stocks by 2017 assuming the BAU and PF scenarios by 2030, and estimate the Carbon balance between the 2030 and 2017 scenarios; and estimate the economic valuation of carbon emission and sequestration by using the InVEST software. The results showed that agriculture (cropped lands) was main driver of the landscape changes in the study area, which increased 14% by 2017, a net increase of 1494.45 km2. The results showed that the total Carbon emissions would reach 736,900 Mg CO 2 -eq by assuming the BAU scenario, which would increase the cost of opportunity up to US$ 17.7 million and a social carbon cost varying between US$ 10.3 and US$ 30.2 million. The restoration of the permanent preservation areas could contribute to increase Carbon sequestration up to 481,900 Mg CO 2 -eq by 2030, which is equivalent cost of US$ 11.6 million. The natural landscape in the Sergipe semiarid region was strongly affected by deforestation activities occurred between 1992 and 2017. It requires, therefore, effective actions to support and promote restoration of degraded areas. The forested areas within the Sergipe semiarid region were the most affected type of vegetation because of expansion of agricultural fields soil exposures (Exposed Land). Environmental assessments based on scenarios and economic valuations can provide crucial information to support policy and decision makers to improve strategies for environmental management and conservation. [ABSTRACT FROM AUTHOR]

Biochar has been used worldwide as an efficient soil amendment due to its beneficial interaction with soil particles and nutrients; however, studies on the effect of biochar on the availability of nutrients such as N and P in tropical soils are still missing. The objective of the study was to evaluate the effect of different types and doses of biochars on the concentration and uptake of N and P in Indian mustard plants (Brassica juncea L.) grown in a Cu contaminated soil during three successive growth cycles. The greenhouse experiment was set up as randomized block design in a 3x3 factorial scheme, with 3 types of biochars (coconut shell, orange bagasse and sewage sludge) and three rates of application (0, 30 and 60t ha-1), and 4 replicates. Biochar increased plant growth by approximately 30 to 224%; however, the orange bagasse biochar was the most effective. Biochar reduced plant N concentration in approximately 15-43%, regardless of the rate of application, indicating the need to carefully adjust N fertilization. In the last growth cycle, biochar from coconut shell and orange bagasse improved the N uptake efficiency suggesting a better amelioration effect with ageing in soil. Biochar did not affect P nutrition in Indian mustard to a great extent; however, it significantly decreased the N:P ratio in the plant. [ABSTRACT FROM AUTHOR]