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1.
Sensors (Basel) ; 21(12)2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34203846

RESUMO

Underlying topography plays an important role in the national economic construction, military security, resource exploration and investigation. Since synthetic aperture radar tomography (TomoSAR) can achieve the three-dimensional imaging of forests, it has been widely used in underlying topography estimation. At present, there are two kinds of TomoSAR based on the applied datasets: single polarimetric TomoSAR (SP-TomoSAR) and fully polarimetric TomoSAR (FP-TomoSAR). However, SP-TomoSAR cannot obtain the underlying topography accurately due to the lack of enough observations. FP-TomoSAR can improve the estimation accuracy of underlying topography. However, it requires high-cost data acquisition for the large-scale application. Thus, this paper proposes the dual polarimetric TomoSAR (DP-TomoSAR) as another suitable candidate to estimate the underlying topography because of its wide swath and multiple polarimetric observations. Moreover, three frequently used spectral estimation algorithms, namely, Beamforming, Capon and MUSIC, are used in DP-TomoSAR. For validation, a series of simulated experiments was carried out, and the airborne P-band multiple polarimetric SAR data over the Lope, Gabon was also acquired to estimate the underlying topography. The results suggest that DP-TomoSAR in HH & HV combination is more suitable to estimate underlying topography over forest areas than other DP combinations. Moreover, the estimation accuracy of DP-TomoSAR is slightly lower than that of FP-TomoSAR but is higher than that of SP-TomoSAR.


Assuntos
Monitoramento Ambiental , Radar , Florestas , Menogaril , Tomografia
2.
Sensors (Basel) ; 21(12)2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34207193

RESUMO

Unmanned aerial vehicles (UAVs) have shown great potential in various applications such as surveillance, search and rescue. To perform safe and efficient navigation, it is vitally important for a UAV to evaluate the environment accurately and promptly. In this work, we present a simulation study for the estimation of foliage distribution as a UAV equipped with biosonar navigates through a forest. Based on a simulated forest environment, foliage echoes are generated by using a bat-inspired bisonar simulator. These biosonar echoes are then used to estimate the spatial distribution of both sparsely and densely distributed tree leaves. While a simple batch processing method is able to estimate sparsely distributed leaf locations well, a wavelet scattering technique coupled with a support vector machine (SVM) classifier is shown to be effective to estimate densely distributed leaves. Our approach is validated by using multiple setups of leaf distributions in the simulated forest environment. Ninety-seven percent accuracy is obtained while estimating thickly distributed foliage.


Assuntos
Florestas , Árvores , Simulação por Computador , Folhas de Planta , Máquina de Vetores de Suporte
3.
Sensors (Basel) ; 21(12)2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34207736

RESUMO

Wildfires have affected global forests and the Mediterranean area with increasing recurrency and intensity in the last years, with climate change resulting in reduced precipitations and higher temperatures. To assess the impact of wildfires on the environment, burned area mapping has become progressively more relevant. Initially carried out via field sketches, the advent of satellite remote sensing opened new possibilities, reducing the cost uncertainty and safety of the previous techniques. In the present study an experimental methodology was adopted to test the potential of advanced remote sensing techniques such as multispectral Sentinel-2, PRISMA hyperspectral satellite, and UAV (unmanned aerial vehicle) remotely-sensed data for the multitemporal mapping of burned areas by soil-vegetation recovery analysis in two test sites in Portugal and Italy. In case study one, innovative multiplatform data classification was performed with the correlation between Sentinel-2 RBR (relativized burn ratio) fire severity classes and the scene hyperspectral signature, performed with a pixel-by-pixel comparison leading to a converging classification. In the adopted methodology, RBR burned area analysis and vegetation recovery was tested for accordance with biophysical vegetation parameters (LAI, fCover, and fAPAR). In case study two, a UAV-sensed NDVI index was adopted for high-resolution mapping data collection. At a large scale, the Sentinel-2 RBR index proved to be efficient for burned area analysis, from both fire severity and vegetation recovery phenomena perspectives. Despite the elapsed time between the event and the acquisition, PRISMA hyperspectral converging classification based on Sentinel-2 was able to detect and discriminate different spectral signatures corresponding to different fire severity classes. At a slope scale, the UAV platform proved to be an effective tool for mapping and characterizing the burned area, giving clear advantage with respect to filed GPS mapping. Results highlighted that UAV platforms, if equipped with a hyperspectral sensor and used in a synergistic approach with PRISMA, would create a useful tool for satellite acquired data scene classification, allowing for the acquisition of a ground truth.


Assuntos
Incêndios , Incêndios Florestais , Florestas , Itália , Portugal
4.
Huan Jing Ke Xue ; 42(7): 3507-3517, 2021 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-34212677

RESUMO

In this study, we hypothesized that the distribution patterns of trace metal elements in montane regions would be controlled by the local climate, human activities, vegetation distribution and soil development. Hence, we selected nine forest sites among the elevation of 850 m to 2650 m on the windward (western slope) and leeward (eastern slope) slopes of Ailao Mountain in Yunnan Province of China to determine the typical heavy metal concentrations in forest surface soils, and their differences for distribution trends along with the increasing elevations, and the corresponding environmental factors. The results showed that surface soil Cd, Sb, As, Cr, and Pb had relatively higher concentrations and distinct enrichment factors both on eastern and western slopes. Specifically, the concentrations of Cd and Sb in surface soils of the eastern and western slopes and Pb on the western slope all had obvious altitude distribution trends, which showed their concentrations increased with the increasing elevation. In addition, we found the concentrations of Cd, Sb, As, and Cr in surface soils of the western slope were significantly higher than those of the eastern slope at the same altitude. The correlation analysis and principal component analysis further depicted that the elevation trends of Cd and Sb were mainly controlled by the strong combining effects from long-range atmospheric input and soil organic matter strong absorption, and there was an obvious "cold trapping" effect in high altitude areas. The distribution variations of As and Cr were mainly derived from the weathering difference of soil parent material, while the variations for Pb were controlled by the weathering of bedrock minerals. This study highlights the important role of combining effects from long-range atmospheric input, and from precipitation and vegetation (such as "cold trapping" effect, promoting canopy filtration, litterfall deposition and bedrock weathering) on the distribution trends of trace metals in remote alpine soils.


Assuntos
Metais Pesados , Poluentes do Solo , China , Monitoramento Ambiental , Florestas , Humanos , Metais Pesados/análise , Solo , Poluentes do Solo/análise
5.
Environ Monit Assess ; 193(8): 459, 2021 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-34216278

RESUMO

It has been established that resurvey of historical vegetation stands, even those not marked permanently, could foster our understanding of vegetation dynamics and changes in structure and composition over time. However, such studies are poorly available, particularly in remote landscapes of the Indian Himalaya. There exists a complete lack of resurveys, which has limited our ability to provide reliable evidence of changes over the decades. This study, for the first time in the Indian Himalaya, considered repeat surveys (nearly after 25 years) of vegetation stands in eleven forest communities of the buffer zone of NDBR (Nanda Devi Biosphere Reserve). Thirty historical forest stands, earlier studied in 1988-1990, were revisited during 2012-2014 and investigated using the same survey methods as used in the previous study. We found that previously reported dominant tree species, i.e., Alnus nepalensis, Acer cappadocicum, Quercus floribunda, Quercus semecarpifolia, Hippophae salicifolia, and Betula utilis, in nine out of eleven communities in the study area are continuing to exhibit dominance in the community. However, a significant increase in species richness and density in the seedling and sapling layer in Quercus floribunda, Quercus semecarpifolia, Rhododendron arboreum, and Abies pindrow is indicative of the ongoing process of change in forest composition. The compositional features of plant communities, when analyzed through Community Change Sensitivity (CCS) approach, identified Quercus floribunda, mixed Quercus-deciduous spp., Hippophae salicifolia, and Abies pindrow as the most change-sensitive communities in the study area and thus can be prioritized as the long-term ecological monitoring sites in the west Himalaya to understand intensity and patterns of changes. The potential changes based on the ecological information from two time period compositional data sets, having conservation and management implications, should be accommodated in the long-term perspective plans of the reserve.


Assuntos
Acer , Quercus , Monitoramento Ambiental , Florestas , Árvores
6.
Sensors (Basel) ; 21(11)2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34200346

RESUMO

Increasing temperatures and drought occurrences recently led to soil moisture depletion and increasing tree mortality. In the interest of sustainable forest management, the monitoring of forest soil properties will be of increasing importance in the future. Vis-NIR spectroscopy can be used as fast, non-destructive and cost-efficient method for soil parameter estimations. Microelectromechanical system devices (MEMS) have become available that are suitable for many application fields due to their low cost as well as their small size and weight. We investigated the performance of MEMS spectrometers in the visual and NIR range to estimate forest soil samples total C and N content of Ah and Oh horizons at the lab. The results were compared to a full-range device using PLSR and Cubist regression models at local (2.3 ha, n: Ah = 60, Oh = 50) and regional scale (State of Saxony, Germany, 184,000 km2, n: Ah = 186 and Oh = 176). For each sample, spectral reflectance was collected using MEMS spectrometer in the visual (Hamamatsu C12880MA) and NIR (NeoSpetrac SWS62231) range and using a conventional full range device (Veris Spectrophotometer). Both data sets were split into a calibration (70%) and a validation set (30%) to evaluate prediction power. Models were calibrated for Oh and Ah horizon separately for both data sets. Using the regional data, we also used a combination of both horizons. Our results show that MEMS devices are suitable for C and N prediction of forest topsoil on regional scale. On local scale, only models for the Ah horizon yielded sufficient results. We found moderate and good model results using MEMS devices for Ah horizons at local scale (R2≥ 0.71, RPIQ ≥ 2.41) using Cubist regression. At regional scale, we achieved moderate results for C and N content using data from MEMS devices in Oh (R2≥ 0.57, RPIQ ≥ 2.42) and Ah horizon (R2≥ 0.54, RPIQ ≥2.15). When combining Oh and Ah horizons, we achieved good prediction results using the MEMS sensors and Cubist (R2≥ 0.85, RPIQ ≥ 4.69). For the regional data, models using data derived by the Hamamatsu device in the visual range only were least precise. Combining visual and NIR data derived from MEMS spectrometers did in most cases improve the prediction accuracy. We directly compared our results to models based on data from a conventional full range device. Our results showed that the combination of both MEMS devices can compete with models based on full range spectrometers. MEMS approaches reached between 68% and 105% of the corresponding full ranges devices R2 values. Local models tended to be more accurate than regional approaches for the Ah horizon. Our results suggest that MEMS spectrometers are suitable for forest soil C and N content estimation. They can contribute to improved monitoring in the future as their small size and weight could make in situ measurements feasible.


Assuntos
Sistemas Microeletromecânicos , Poluentes do Solo , Florestas , Alemanha , Solo , Poluentes do Solo/análise
7.
Artigo em Inglês | MEDLINE | ID: mdl-34214026

RESUMO

A novel actinomycete, designated strain KK5PA1T, was isolated from a soil sample collected from Kuan Kreng peat swamp forest, Nakhon Si Thammarat Province, Thailand. The morphological, chemotaxonomic and phylogenetic characteristics were consistent with its classification in the genus Streptomyces. Strain KK5PA1T was most closely related to Streptomyces bryophytorum NEAU-HZ10T (98.0 %) and Streptomyces guanduensis 701T (97.6 %). The G+C content of the genomic DNA was 72.3 mol%. Digital DNA-DNA hybridization and average nucleotide identity values between the genome sequence of strain KK5PA1T and those of S. bryophytorum DSM 42138T(25.1 and 79.1 %) and S. guanduensis DSM 41944T(25.1 and 79.7%) were below the thresholds of 70 and 96 % for prokaryotic conspecific assignation. Chemotaxonomic data revealed that strain KK5PA1T possessed MK-9(H6) and MK-9(H8) as the predominant menaquinones. It contained ll-diaminopimelic acid as the diagnostic diamino acid and galactose, glucose, mannose and ribose as whole-cell sugars. The polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol mannoside, two unidentified aminolipids, five unidentified phospholipids and an unidentified lipid. The predominant cellular fatty acids were iso-C16 : 0, anteiso-C15 : 0 and C16 : 0. On the basis of these genotypic and phenotypic data, it is proposed that strain KK5PA1T represents a novel species of the genus Streptomyces, for which the name Streptomyces acididurans sp. nov. is proposed. The type strain is strain KK5PA1T (=TBRC 13094T=NBRC 114802T).


Assuntos
Filogenia , Microbiologia do Solo , Streptomyces/classificação , Áreas Alagadas , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Florestas , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Streptomyces/isolamento & purificação , Tailândia , Vitamina K 2/análogos & derivados , Vitamina K 2/química
8.
Artigo em Inglês | MEDLINE | ID: mdl-34241587

RESUMO

A novel bacterial strain, designated K2CV101002-2T, was isolated from forest soil collected at Dinghushan Biosphere Reserve, Guangdong Province, PR China. Phylogenetic analyses based on 16S rRNA gene sequences showed that it belonged to the genus Chitinophaga and was most closely related to Chitinophaga terrae KP01T (99.0 %), followed by Chitinophaga extrema Mgbs1T (98.3 %) and Chitinophaga solisilvae O9T (98.1 %). The draft genome sequence was 6.8 Mb long with a relative low G+C content of 39.8 mol%. The average nucleotide identity and digital DNA-DNA hybridization values between the novel strain and closely related type strains were 71.4‒76.2 % and 18.4‒19.6 %, respectively. Meanwhile the corresponding values between C. extrema Mgbs1T and C. solisilvae O9T were 98.6 and 88.1 %, respectively. The novel strain contained iso-C15:0, C16:1 ω5c and iso-C17:0 3-OH as the major fatty acids and MK-7 as the predominant respiratory quinone. The polyphasic study clearly supported that strain K2CV101002-2T represents a new species of the genus Chitinophaga, for which the name Chtinophaga silvatica sp. nov. (type strain K2CV101002-2T=GDMCC 1.1288T=JCM 32696T) is proposed. In addition, Chitinophaga extrema Goh et al. 2020 should be taken as a later heterotypic synonym of Chitinophaga solisilvae Ping et al. 2020.


Assuntos
Bacteroidetes/classificação , Florestas , Filogenia , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Bacteroidetes/isolamento & purificação , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
9.
Artigo em Inglês | MEDLINE | ID: covidwho-1270030

RESUMO

This study was conducted to verify the perceived restorativeness of citizens visiting forests on social-psychological stress and psychological resilience according to forest space type. The study involved a questionnaire survey conducted on citizens who visited forests between 1 May and 15 July 2020, when social distancing in daily life was being implemented. Three types of forest spaces (urban forest, national park, and natural recreation forest) were selected for the survey. They used the survey results of 1196 people as analysis data for this study. In this study, the PRS (Perceived Restorativeness Scale) and the PWI-SF (Psychosocial Well-being Index Short Form) were used to evaluate perceived restorativeness and social-psychological stress of citizens visiting forests. In the study, the average score of visitors' perceived restorativeness was 5.31 ± 0.77. Social-psychological stress was found in the healthy group, potential stress group, and high-risk group. These groups made up 8.0%, 82.5%, and 9.5% of the respondents, respectively. Pearson's correlation analysis between perceived restorativeness and social-psychological stress revealed that the higher the perceived restorativeness, the lower the social-psychological stress. "Diversion Mood", "Not bored", and "Coherence", which are the sub-factors of perceived restorativeness according to the forest space type, were found to have meaningful results for psychological resilience. However, there was no significant difference in the forest space type between "Compatibility" and social-psychological stress, which are sub-factors of perceived restorativeness. In conclusion, the forest space type affects the psychological resilience of those who visit the forest. Urban forests, national parks, and natural recreation forests are places to reduce stress.


Assuntos
Florestas , Estresse Psicológico , Humanos , Parques Recreativos , Inquéritos e Questionários
10.
Artigo em Inglês | MEDLINE | ID: mdl-34208025

RESUMO

This study was conducted to verify the perceived restorativeness of citizens visiting forests on social-psychological stress and psychological resilience according to forest space type. The study involved a questionnaire survey conducted on citizens who visited forests between 1 May and 15 July 2020, when social distancing in daily life was being implemented. Three types of forest spaces (urban forest, national park, and natural recreation forest) were selected for the survey. They used the survey results of 1196 people as analysis data for this study. In this study, the PRS (Perceived Restorativeness Scale) and the PWI-SF (Psychosocial Well-being Index Short Form) were used to evaluate perceived restorativeness and social-psychological stress of citizens visiting forests. In the study, the average score of visitors' perceived restorativeness was 5.31 ± 0.77. Social-psychological stress was found in the healthy group, potential stress group, and high-risk group. These groups made up 8.0%, 82.5%, and 9.5% of the respondents, respectively. Pearson's correlation analysis between perceived restorativeness and social-psychological stress revealed that the higher the perceived restorativeness, the lower the social-psychological stress. "Diversion Mood", "Not bored", and "Coherence", which are the sub-factors of perceived restorativeness according to the forest space type, were found to have meaningful results for psychological resilience. However, there was no significant difference in the forest space type between "Compatibility" and social-psychological stress, which are sub-factors of perceived restorativeness. In conclusion, the forest space type affects the psychological resilience of those who visit the forest. Urban forests, national parks, and natural recreation forests are places to reduce stress.


Assuntos
Florestas , Estresse Psicológico , Humanos , Parques Recreativos , Inquéritos e Questionários
11.
Molecules ; 26(11)2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34199646

RESUMO

Wild ginseng (W-GS), ginseng under forest (F-GS, planted in mountain forest and growing in natural environment), and cultivated ginseng (C-GS) were compared via HPLC-DAD and HPLC-IT-TOF-MSn. A total of 199 saponins, including 16 potential new compounds, were tentatively identified from 100 mg W-GS (177 saponins in W-GS with 11 new compounds), F-GS (56 saponins with 1 new compound), and C-GS (60 saponins with 6 new compounds). There were 21 saponins detected from all the W-GS, F-GS, and C-GS. Fifty saponins were only detected from W-GS, including 23 saponins found in ginseng for the first time. Contents of ginsenosides Re (12.36-13.91 mg/g), Rh1 (7.46-7.65 mg/g), Rd (12.94-12.98 mg/g), and the total contents (50.52-55.51 mg/g) of Rg1, Re, Rf, Rb1, Rg2, Rh1, and Rd in W-GS were remarkably higher than those in F-GS (Re 1.22-3.50 mg/g, Rh1 0.15-1.49 mg/g, Rd 0.19-1.49 mg/g, total 5.69-18.74 mg/g), and C-GS (Re 0.30-3.45 mg/g, Rh1 0.05-3.42 mg/g, Rd 0.17-1.68 mg/g, total 2.99-19.55 mg/g). Contents of Re and Rf were significantly higher in F-GS than those in C-GS (p < 0.05). Using the contents of Re, Rf, or Rb1, approximately a half number of cultivated ginseng samples could be identified from ginseng under forest. Contents of Rg1, Re, Rg2, Rh1, as well as the total contents of the seven ginsenosides were highest in ginseng older than 15 years, middle-high in ginseng between 10 to 15 years old, and lowest in ginseng younger than 10 years. Contents of Rg1, Re, Rf, Rb1, Rg2, and the total of seven ginsenosides were significantly related to the growing ages of ginseng (p < 0.10). Similarities of chromatographic fingerprints to W-GS were significantly higher (p < 0.05) for F-GS (median: 0.824) than C-GS (median: 0.745). A characteristic peak pattern in fingerprint was also discovered for distinguishing three types of ginseng. Conclusively, wild ginseng was remarkably superior to ginseng under forest and cultivated ginseng, with ginseng under forest slightly closer to wild ginseng than cultivated ginseng. The differences among wild ginseng, ginseng under forest, and cultivated ginseng in saponin compositions and contents of ginsenosides were mainly attributed to their growing ages.


Assuntos
Panax/crescimento & desenvolvimento , Saponinas/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Florestas , Estrutura Molecular , Panax/química , Panax/classificação , Saponinas/química
12.
Artigo em Inglês | MEDLINE | ID: mdl-34255622

RESUMO

Two Gram-stain-negative, yellow-pigmented and strictly aerobic bacteria, designated strains SE-s27T and SE-s28T, were isolated from forest soil. Both strains were non-motile rods that were catalase-positive and oxidase-negative and grew optimally at 25-30 °C, pH 8.0 and with 0 % (w/v) NaCl. Strain SE-s28T produced flexirubin-type pigments, but strain SE-s27T did not produce them. Both strains contained menaquinone-6 as the sole respiratory quinone and phosphatidylethanolamine as a major polar lipid. As the major cellular fatty acids (>10 %), SE-s27T contained iso-C15 : 1 and iso-C15 : 1G, whereas SE-s28T contained iso-C15 : 0 and summed feature 3 comprising C16 : 1ω7c and/or C16 : 1ω6c and/or iso-C15 : 0 2-OH. The DNA G+C contents of strains SE-s27T and SE-s28T were 33.1 and 44.3 mol%, respectively. The results of phylogenetic analysis based on 16S rRNA gene sequences revealed that SE-s27T and SE-s28T formed respective distinct phylogenetic lineages within the genus Flavobacterium. Strains SE-s27T and SE-s28T were most closely related to Flavobacterium macrobrachii an-8T and Flavobacterium piscinae ICH-30T with 98.0 and 94.5 % 16S rRNA gene sequence similarities, respectively. In conclusion, strains SE-s27T and SE-s28T represent novel species of the genus Flavobacterium, for which the names Flavobacterium solisilvae sp. nov. and Flavobacterium silvaticum sp. nov. are proposed. The type strains of F. solisilvae and F. silvaticum are SE-s27T (=KACC 18802T=JCM 31544T) and SE-s28T (=KACC 18803T=JCM 31545T), respectively.


Assuntos
Flavobacterium/classificação , Florestas , Filogenia , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Flavobacterium/isolamento & purificação , Fosfatidiletanolaminas , Pigmentação , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
13.
Mem Inst Oswaldo Cruz ; 116: e210064, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34259737

RESUMO

Unforeseen Plasmodium infections in the Atlantic Forest of Brazilian Extra-Amazonian region could jeopardise malaria elimination. A human malaria case was registered in Três Forquilhas, in the Atlantic Forest biome of Rio Grande do Sul, after a 45 years' time-lapsed without any malaria autochthonous notification in this southern Brazilian state. This finding represents the expansion of the malaria distribution areas in Brazil and the southernmost human malaria case record in South America in this decade. The coexistence of the bromeliad-breeding vector Anopheles (Kerteszia) cruzii and non-human primates in the Atlantic Forest regularly visited by the patient claimed for the zoonotic origin of this infection. The reemergence of Atlantic Forest human malaria in Rio Grande do Sul was also discussed.


Assuntos
Anopheles , Malária , Animais , Brasil/epidemiologia , Florestas , Humanos , Malária/epidemiologia , Mosquitos Vetores
14.
Ying Yong Sheng Tai Xue Bao ; 32(6): 1928-1934, 2021 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34212596

RESUMO

Water cycle in the soil-plant-atmosphere continuum (SPAC) is an important research topic in hydrology and ecology. The differences in the composition of hydrogen and oxygen stable isotopes in different water bodies can indicate water cycle process. Based on the measurements of isotopic compositions in precipitation, soil water, and plant water, we analyzed water isotope evolution in a SPAC system located in a subtropical evergreen broad-leaved forest in Chengdu Plain. The different interface processes of regional water cycle was revealed. The results showed that the local meteoric water line (LMWL) equation was δD=7.13 δ18O+2.35 (R2=0.99), and the soil evaporation line (SEL) equation was δD=6.98δ18O-0.32 (R2=0.92). In the water transportation process of precipitation-soil water-plant water, hydrogen and oxygen isotopes were gradually enriched. The δ18O in water of the surface soil layer (0-35 cm) was sensitive to precipitation input, as it was directly affected by precipitation. In contrast, the δ18O in water of the middle and deep layers (35-100 cm) was relatively stable. The isotopes of plant xylem water were slightly more enriched than those of soil water, indicating the possibility of slight evaporation or transpiration through phloem or bark in plant water transportation. The estimation of plant water intake from different soil layers was performed by direct correlation method. Cinnamomum camphora mainly used water from the middle layer, Broussonetia papyrifera mainly used that from the surface layer, and Parathelypteris glanduligera tended to use surface soil water and precipitation intercepted by plants because of the shallow root system. Compared with P. glanduligera, C. camphora and B. papyrifera experienced stronger water evaporation and the isotopes were influenced by more intense dynamic fractionation.


Assuntos
Hidrogênio , Solo , Atmosfera , Florestas , Oxigênio , Isótopos de Oxigênio/análise , Água
15.
Ying Yong Sheng Tai Xue Bao ; 32(6): 2053-2060, 2021 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34212611

RESUMO

We explored the effects of disturbance densities on the spatial pattern and the association of tree species in the coniferous broadleaved mixed forest in Pangquangou Nature Reserve of Guandi Mountain. Using three factors including canopy density, stand density and number of stumps, we classified the disturbance intensities of different forest stands into three levels, non-disturbance, moderate disturbance, and severe disturbance. The spatial distribution pattern and the association of different tree species were analyzed by spatial point pattern K2 function. The results showed that the diameter distribution of trees in undisturbed plots was inverted 'J' type, while that of moderate disturbance and serious disturbance plots was under bimodal curve distribution. The stand distribution pattern showed a small-scale aggregated distribution under undisturbed and moderately distur-bance, and a random distribution under heavy disturbance. At the small scale, the coniferous and broadleaved species showed no correlation in undisturbed stands, were positively correlated in moderately disturbed stands, and negatively correlated in seriously disturbed stands. At large scale, they were no correlated in both moderately and seriously disturbed stands. The results suggested that abundance of trees with small diameter in the forests was negatively with disturbance intensity, which led to the lower degree of intraspecific aggregation at small scale. Meanwhile, appropriate levels of disturbance would benefit the collaborative use of environmental resources for trees. Our results revealed the impacts of disturbance density on forest community structure and could provide theoretical basis for forest management.


Assuntos
Picea , Pinus , Traqueófitas , China , Florestas , Árvores
16.
Ying Yong Sheng Tai Xue Bao ; 32(6): 2061-2069, 2021 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34212612

RESUMO

The adaptation strategy of seedlings plays a decisive role in population regeneration. Machilus nanmu is a tree species belonging to Lauraceae, which is national class Ⅱ protected species and one of the dominant species in the evergreen broadleaved forest in Jinyun Mountain, Chongqing. Therefore, it is of great significance to understand the adaptation strategies of M. nanmu seedlings to maintain population regeneration and protect the biodiversity of evergreen broadleaved forest. We studied the temporal dynamics of early adaptation strategy of M. nanmu in Jinyun Mountain in Chongqing and its response to heterogeneous habitats from the perspective of morphology and biomass allocation. The seedlings of M. nanmu were classified into different age stages (stage 1: 1-3 a; stage 2: 4-6 a; stage 3: 7-9 a) under different canopy environments (gap/understory). Stem configurations (except branch angle) and leaf inclination angle of M. nanmu seedlings in the gap were significantly greater than understory at stages 2 and 3. Root configurations (except root diameter) and leaf area were significantly greater than that in the understory at stages 1 and 2. Specific leaf area in the gap was significantly smaller than understory at all three stages. Across all the conditions, biomass distribution was dominated by leaves. From the stage 2, stem biomass distribution of M. nanmu seedlings in the gap was increased, while root biomass distribution was decreased. There was no significant variation in root biomass of M. nanmu seedlings in the understory. The coordination among different organs of M. nanmu seedlings would help their adaptation to different habitats. Root and leaf of M. nanmu seedlings in the gap were significantly correlated, with the correlation changing from positive to negative as the age increased. While in the understory, there was significant positive correlation between root and stem, but no correlation between root and leaf. The slope of SMA equation of branch weight and branch length had significant difference under different canopy environments only at stage 3, while the slope of SMA equation of leaf and root biomass and configuration had no significant difference. Most of the SMA equation intercepts between biomass and configuration differed significantly at stage 2.


Assuntos
Lauraceae , Plântula , Biomassa , Florestas , Folhas de Planta , Árvores
17.
Braz J Biol ; 83: e243245, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34133489

RESUMO

Although richness and distribution of woody species in the Cerrado physiognomies have been extensively studied, the shifts of woody species from savanna physiognomies to dry forests have not yet been addressed. Here, we investigate the effect of soil physical-chemical traits on the woody species turnover between adjacent cerrado stricto sensu and dry forest physiognomies. Woody species were surveyed, and soil and topographic variables measured, in 30 10×40 m plots systematically distributed, with 15 plots in each physiognomy. We found a spatially structured distribution of woody species, and differences of soil traits between cerrado stricto sensu and dry forest areas, mainly related to the aluminum saturation, base saturation, and available phosphorus. Aluminum saturation increased toward the savanna area, while base saturation increased toward the dry forest. Most woody species predominated in one physiognomy, such as Callisthene major in the cerrado stricto sensu and Anadenanthera colubrina in the dry forest. Only 20% of the species were widely distributed across both physiognomies or, not often, restricted to the intermediary values of the soil gradient. General results indicate that contrasting soil traits between cerrado stricto sensu and dry forest produce a strongly spatially organized and sharp transition in terms of species distribution between these physiognomies.


Assuntos
Pradaria , Solo , Brasil , Florestas , Árvores
18.
Chemosphere ; 279: 130511, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34134400

RESUMO

In this paper, cesium (Cs) accumulation by the saprophytic fungus Lentinula edodes (Shiitake) was investigated to contribute to the elucidation of radiocesium-cycling mechanisms in forest environments. Although the 137Cs in the mushroom bed before culture was bioavailable, the transfer factor (TF) of Cs (133Cs and 137Cs) from the mushroom bed to fruit bodies was low (approximately 1) and the TFs of K (5) and Na (1.5) were higher. Cs and K concentrations in fruit bodies at different maturity stages were almost constant. The concentration ratio of Cs/K is constant in the pileus regardless of the pileus tissues. These results demonstrate that Shiitake non-specifically accumulates Cs while accumulating the essential element K and provide evidence that no selective Cs accumulation (or binding) sites exist within the Shiitake fruit body. Furthermore, the present results show that most accumulated Cs quickly leaches out from the dead fruit body with exposure to water. The leached Cs was largely adsorbable on clay minerals, suggesting that the Shiitake fruit body likely contains Cs in the cation form.


Assuntos
Cogumelos Shiitake , Florestas , Frutas , Água
19.
Zootaxa ; 4974(3): 596599, 2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34186579

RESUMO

Melanocryptus Cameron, 1902 is a neotropical genus with 11 described species (Yu et al. 2016). The first three species of the genus were originally placed in different genera: Melanocryptus Cameron (1902), Lobocryptus Schmiedeknecht (1904) and Hoplophorina Szépligeti (1916). Townes Townes (1966) placed these species into a single taxon, Melanocryptus, and included the genus as part of the subtribe Mesostenina (apud Aguiar Santos, 2015). Despite this original placement, in 1970, Townes created an exclusive subtribe Melanocryptina for the genus.


Assuntos
Himenópteros/classificação , Animais , Brasil , Florestas
20.
Zootaxa ; 4974(3): 401458, 2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34186586

RESUMO

The present paper has two aims: 1) to present the results of the study of selected species of Orthoptera Tettigoniidae collected in the Guinean forests of West Africa and in the important hotspot of Dzanga-Ndoki National Park (Central African Republic); 2) to carry out a check-list of six subfamilies of Tettigoniidae (Pseudophyllinae, Conocephalinae, Hexacentrinae, Phaneropterinae, Mecopodinae and Hetrodinae) living in Central-West tropical Africa, in particular in two main tropical forests, in the subregion of upper Guinea, and in the subregion Nigeria-Cameroon plus the biodiversity hotspots of Central African Republic and Gabon. Many new records are reported and the following new species are described: Plangia astylata n. sp. from Central African Republic and Gabon, Plangia chopardi n. sp. from Côte d'Ivoire, and Catoptropteryx lineata n. sp. from Liberia. In addition the male of Plangia karschi Chopard, 1954 is described and some taxonomical notes on the recently described Arantia marginata Massa, 2021 are discussed. The new name Pseudorhynchus raggei is proposed for Pseudorhynchus robustus Ragge, 1969, junior primary homonym of Pseudorhynchus robustus Willemse, 1953. Then, the author lists all the Tettigoniidae of the above listed subfamilies presently known in central-west tropical Africa (Guinean forests). This wide tropical area holds important biodiversity hotspots that the author highlights through the study of katydids. Many groups of species tend to isolate and speciate probably more than other groups of insects. Overall, the total number amounts to 332 species, of which 242 live in Cameroon-Nigeria subregion plus Central African Republic and Gabon, 216 in the Upper Guinea subregion. The occurrence of endemic taxa is 35.9 and 40.3%, respectively; this resulted a very high percentage compared to that known for plants and animals in the area. Starting from the list of Tettigoniidae three remarkable biodiversity hotspots were examined, Dzanga-Ndoki National Park (Central African Republic), Mt. Tonkoui and Taï National Park (both in Côte d'Ivoire); overall they hold 134, 81 and 88 species, respectively. It seems that in tropical Africa there is a specific richness gradient with an East-West impoverishment, but also a possible increase of endemism occurrence. However, presently this richness suffers a high decline risk, due to deforestation and environmental degradation, in turn dependent on the inequality between human populations, wars and political instability in some tropical areas.


Assuntos
Ortópteros/classificação , Distribuição Animal , Animais , Biodiversidade , Florestas , Guiné , Masculino
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