198 research outputs found

    Forgotten forests - issues and prospects in biome mapping using Seasonally Dry Tropical Forests as a case study

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    <p>Abstract</p> <p>Background</p> <p>South America is one of the most species diverse continents in the world. Within South America diversity is not distributed evenly at both local and continental scales and this has led to the recognition of various areas with unique species assemblages. Several schemes currently exist which divide the continental-level diversity into large species assemblages referred to as biomes. Here we review five currently available biome maps for South America, including the WWF Ecoregions, the Americas basemap, the Land Cover Map of South America, Morrone's Biogeographic regions of Latin America, and the Ecological Systems Map. The comparison is performed through a case study on the Seasonally Dry Tropical Forest (SDTF) biome using herbarium data of habitat specialist species.</p> <p>Results</p> <p>Current biome maps of South America perform poorly in depicting SDTF distribution. The poor performance of the maps can be attributed to two main factors: (1) poor spatial resolution, and (2) poor biome delimitation. Poor spatial resolution strongly limits the use of some of the maps in GIS applications, especially for areas with heterogeneous landscape such as the Andes. Whilst the Land Cover Map did not suffer from poor spatial resolution, it showed poor delimitation of biomes. The results highlight that delimiting structurally heterogeneous vegetation is difficult based on remote sensed data alone. A new refined working map of South American SDTF biome is proposed, derived using the Biome Distribution Modelling (BDM) approach where georeferenced herbarium data is used in conjunction with bioclimatic data.</p> <p>Conclusions</p> <p>Georeferenced specimen data play potentially an important role in biome mapping. Our study shows that herbarium data could be used as a way of ground-truthing biome maps <it>in silico</it>. The results also illustrate that herbarium data can be used to model vegetation maps through predictive modelling. The BDM approach is a promising new method in biome mapping, and could be particularly useful for mapping poorly known, fragmented, or degraded vegetation. We wish to highlight that biome delimitation is not an exact science, and that transparency is needed on how biomes are used as study units in macroevolutionary and ecological research.</p

    Bacterial structure of agricultural soils with high and low yields.

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    The purpose of this study was to evaluate the structure of bacterial communities at two agricultural fields in Brazil (Paraná (PR) and Bahia (BA) states) with a history of high and low productivity of soybean. 16S rRNA gene amplicons revealed that plots with low yield of grains showed greater bacterial richness than plots with high yield. The phylum Acidobacteria was more abundant in soil samples from PR site. The rhizosphere of plants presented a similar bacterial community for both high and low yield plots. Soil samples from BA showed differences in the diversity between the plots with high and low productivity. The use of 16S rRNA amplicon sequencing allowed the assessment of differences between plots with different soybean yields. This might be useful in the future to harness plant microbiomes for increased crop productivity

    Uso de classificadores para o mapeamento da vegetação nativa de cerrado.

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    ABSTRACT- The environment is in constant change, and for a better comprehension of these changes it is necessary observations with an amplitude of temporal and spatial scales. The use of geoprocessing and remote sensing techniques to identify the modifications promoted by human race in the environment are becoming more frequent, highlighting the monitoring of deforestation and illegal burning. In this work the objective was to realize the mapping of savannah native vegetation using an image CCD/CBERS-2 and the classification methods visual, supervised and non supervised. The work was realized in the municipal district of Gurupi, TO, coordinates 11° 44' 47" S and 49° 04' 15" W. The delimitation of the area was defined by the map SC-22-Z-DIV-4-NE from the Brazilian Institute of Geography and Statistics (IBGE), scale of 1:25.000, with a total area of 19,093.19 ha. After the image registration it was obtained a mean error of 0.48 pixel or 9.6 m. After the classification using the different methods it is possible to say that for local conditions, the visual and supervised classifications were the most indicated, mapping an area of 6,112.19 and 4,173.40 ha, respectively. The non supervised classification mapped an area of 6,646.00 ha. The exactitude indices were considered excellent for visual and supervised classification. The previous knowledge about the area was indispensable to the results of the visual and supervised classifications. A non supervised classification with a reduced number of classes could reduce the excess of similar classes and increase the exactitude indices for the classification, according to local conditions

    ECOLOGICAL SERVICES OF AGROFORESTRY LANDSCAPES IN SELECTED WATERSHED AREAS IN THE PHILIPPINES AND INDONESIA

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    This article argues that the practice of agroforestry provides ecological contributions to the smallholder farmers cultivating in the watershed areas. Specifically, this farming system provides contribution to carbon sequestration potential of the woody perennials and the biodiversity conservation of the other components of the system.   This argument is based on the research conducted in Molawin-Dampalit Sub-Watershed, Mt. Makiling Forest Reserve in the Philippines and Way Betung Watershed in Indonesia.  The research involved an interview session of 106 and 261 smallholder farmers and an assessment of 27 and 14 agroforesty plots for carbon stock assessment and biodiversity assessment, respectively. Results indicated that the total carbon found among the crop components was 52.32 MgC/ha in Molawin-Dampalit Sub-Watershed­ and 244.26 MgC/ha in Way Betung Watershed­, which suggested the high carbon sequestration potential of the woody perennials and understory crops in an agroforestry system.  The farm lots being cultivated by the smallholder farmers were found to contribute to biodiversity conservation having a moderate biodiversity index of 2.59 and 2.53, respectively.  With these findings, promotion of desired agroforestry systems in suitable portions of the watershed areas should be intensified and heightened to contribute to ecological balance across the landscape.  Agroforestry should always be an integral part of all initiatives toward ecological restoration with the cultivators/smallholder farmers as potential partners.  The agroforestry system should consider all the technical and socioeconomic considerations toward having diverse components and ensure food security among the smallholder farmers throughout the year

    Ecological Services of Agroforestry Landscapes in Selected Watershed Areas in the Philippines and Indonesia

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    This article argues that the practice of agroforestry provides ecological contributions to the smallholder farmers cultivating in the watershed areas. Specifically, this farming system provides contribution to carbon sequestration potential of the woody perennials and the biodiversity conservation of the other components of the system. This argument is based on the research conducted in Molawin-Dampalit Sub-Watershed, Mt. Makiling Forest Reserve in the Philippines and Way Betung Watershed in Indonesia. The research involved an interview session of 106 and 261 smallholder farmers and an assessment of 27 and 14 agroforesty plots for carbon stock assessment and biodiversity assessment, respectively. Results indicated that the total carbon found among the crop components was 52.32 MgC/ha in Molawin-Dampalit Sub-Watershed­ and 244.26 MgC/ha in Way Betung Watershed­, which suggested the high carbon sequestration potential of the woody perennials and understory crops in an agroforestry system. The farm lots being cultivated by the smallholder farmers were found to contribute to biodiversity conservation having a moderate biodiversity index of 2.59 and 2.53, respectively. With these findings, promotion of desired agroforestry systems in suitable portions of the watershed areas should be intensified and heightened to contribute to ecological balance across the landscape. Agroforestry should always be an integral part of all initiatives toward ecological restoration with the cultivators/smallholder farmers as potential partners. The agroforestry system should consider all the technical and socioeconomic considerations toward having diverse components and ensure food security among the smallholder farmers throughout the year

    The state of the Martian climate

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    60°N was +2.0°C, relative to the 1981–2010 average value (Fig. 5.1). This marks a new high for the record. The average annual surface air temperature (SAT) anomaly for 2016 for land stations north of starting in 1900, and is a significant increase over the previous highest value of +1.2°C, which was observed in 2007, 2011, and 2015. Average global annual temperatures also showed record values in 2015 and 2016. Currently, the Arctic is warming at more than twice the rate of lower latitudes
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