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1.
Environ Monit Assess ; 192(4): 239, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32185492

RESUMO

In order to determine the stand age in the uneven-aged natural forest, a dynamic prediction model of stand volume and biomass was established in this study. In the model, the site quality grade was used as the dumb variable and the interval was used as the independent variable. In addition, the parameters of the model were estimated using immune evolutionary algorithm. The model was verified with the field data and the result revealed that the model had high accuracy. On this basis, the dynamic prediction model for forest stock was applied to evaluate the asset evaluation of uneven-aged natural forest and estimate carbon storage/sink potential of forest biomass. The selective logging period of the forest in the four plots was determined at the selective logging intensity of 40%. However, at the selective logging intensity of 40%, the forest ecological environment was suffered from the adverse effect to a certain extent from the perspective of scientific management, diversity of species, etc. Based on the comprehensive consideration of all the factors, it is recommended to set the selective cutting intensity in the range of 30 to 35%. The results can provide technical support for the application of selective logging income method in asset evaluation. Therefore, the results of this study have theoretical significance and practical application value in dynamic prediction of forest resources, asset evaluation and management, decision-making, etc.


Assuntos
Sequestro de Carbono , Monitoramento Ambiental , Florestas , Pinus , Biomassa , Pinus/crescimento & desenvolvimento , Árvores
2.
Sci Total Environ ; 692: 691-700, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31539977

RESUMO

In the last decades, land-use changes have made Mediterranean forests highly susceptible to wildfires, which can cause several impacts not only on burnt areas, but also on adjacent aquatic ecosystems. Post-fire runoff from burnt areas may transport toxic substances to streams by surface runoff, including polycyclic aromatic hydrocarbons (PAHs) and metals, which can be noxious to aquatic organisms. Impacts on aquatic ecosystems can be related to fire severity, forest type and the exposure period; however, these factors have not been investigated in tandem. Here, we used the stream detrital system to determine the impacts of post-fire runoffs and stream water from a burnt catchment on trophic interactions between stream microbial communities and invertebrate shredders involved in leaf litter decomposition. Three distinct types of samples were collected from a burnt catchment: post-fire runoffs from high severity wildfires in Pinus and Eucalyptus forests, and stream water. Microbial decomposer communities (fungi and bacteria) and the invertebrate shredder Allogamus ligonifer were exposed for 10 and 20 days to increasing concentrations (0, 50, 75 and 100%) of runoff extracts. Our results showed that post-fire runoffs from high severity wildfires reduced microbially-driven leaf litter decomposition (up to 79%), invertebrate feeding (up to 75%), fungal biomass (up to 39%) and altered community composition; effects were more severe at the longer exposure time. The impacts varied with the runoff source and were related to the chemical composition in metals and total PAHs. This study emphasizes the importance of assessing the indirect effects of wildfires taking into account the effects of the runoff source, load and exposure time on freshwater biota and their ecological functions. Therefore, best forest management practices should be applied to minimize post-fire runoffs reaching aquatic ecosystems and to reduce the effects of these extreme events on freshwater biodiversity and ecosystem functioning.


Assuntos
Cadeia Alimentar , Agricultura Florestal , Água Doce/química , Microbiota , Movimentos da Água , Incêndios Florestais , Eucalyptus/crescimento & desenvolvimento , Florestas , Pinus/crescimento & desenvolvimento , Portugal , Fatores de Tempo
3.
Environ Monit Assess ; 191(9): 541, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31385054

RESUMO

Biophysical parameters affecting biomass carbon have been emphasized in the Paris Agreement for realizing climatic benefits from mitigation projects. The present study was conducted to assess the relation of biophysical parameters with forest biomass carbon in north Kashmir region of Himalayas. The relation of biomass carbon was assessed with (1) species type or strata including Cedrus deodara, mixed I (Cedrus deodara-Pinus wallichiana), mixed II (Abies pindrow-Picea smithiana) and Pinus wallichiana, (2) altitude (1292-2911 m amsl), (3) crown density, (4) aspect, (5) tree count or density and (6) location. Using a stratified sampling design, a total of 188 quadrats of 0.1 ha were laid across the entire region representing different biophysical parameters. Field observation including diameter at breast height and height were recorded and sample biomass (t ha-1) was estimated using volumetric equations. The observed relation of aboveground biomass carbon with species revealed a trend of mixed II ˃ Cedrus deodara ˃ mixed I ˃ Pinus wallichiana. A positive but weak correlation (R2 = 0.02) was found between aboveground biomass carbon and altitude. A reasonably good correlation (R2 = 0.40) was observed to exist between aboveground biomass carbon and crown density. The highest value of average biomass carbon (72.63 t ha-1) was recorded for the north-eastern aspect whereas the lowest value (44.60 t ha-1) was recorded for the eastern aspect. The aboveground biomass carbon and tree count was found positively correlated (+ 0.475, R2 = 0.48). Forest biomass carbon fluctuates within the same geographical region with a variety of biophysical factors. The growth rate of species, photosynthetic ability under different crown densities and climatic conditions could address the reasons for this variability. Biophysical relations of forest biomass carbon can be viewed as an important input for guidelines and policy matters on climate change.


Assuntos
Biomassa , Carbono/análise , Cedrus/crescimento & desenvolvimento , Mudança Climática/estatística & dados numéricos , Monitoramento Ambiental/métodos , Pinus/crescimento & desenvolvimento , Altitude , Florestas , Índia , Paquistão , Árvores/crescimento & desenvolvimento
4.
Ying Yong Sheng Tai Xue Bao ; 30(8): 2583-2590, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31418181

RESUMO

We explored the effects of microtopography changes from artificial intervention of soil and water conservation (contour reverse-slope terrace, CRT) on tree growth in a degraded woodland on hillslope in water resource area of Songhua dam in Kunming City. The differences of the diameter at breast height (DBH), tree height, new branch increment, and leaf area index (LAI) of dominant tree species in different plots were compared through dynamic monitoring. Then, the causes of differences were analyzed by combining the soil water availability. The results showed that the maximum and mean values of DBH and height of Pinus yunnanensis (dominant species) in contour reverse-slope terrace plot were larger than those in control plot (CK), and the proportion of small-sized and low-dwarf trees in degraded forest community was higher, which indicated that the growth potential of new and seriously degraded forest was stimulated. The annual variation rate of the ave-rage new branch length and diameter of P. yunnanensis in different plots reached 72.4% and 39.1%, respectively. The changes of new branch growth of P. yunnanensis, LAI of plots, and the new branch growth rate were greater in CRT than those in CK. Soil water content was significantly correlated with both the new branch growth and LAI. The ratio of available water in plot (64.2%) was higher than that in CK (54.7%). During the rainy season (from May to September), the available water in CRT existed longer, which was conducive to tree growth and the improvement of plant community structure in degraded woodland.


Assuntos
Conservação dos Recursos Naturais/métodos , Florestas , Pinus/crescimento & desenvolvimento , Agricultura Florestal , Folhas de Planta , Solo , Árvores
5.
Ying Yong Sheng Tai Xue Bao ; 30(7): 2231-2240, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31418225

RESUMO

With dendrochronology method, standard and residual chronologies of Pinus massoniana were established at low altitude (260 m), middle altitude (460 m), high altitude (690 m), sunny slope (270 m), and shady slope (265 m). Relationships between the tree-ring width and the climatic factors were quantified using correlation analysis and redundancy analysis (RDA). The optimal multiple regression models for the radial growth of P. massoniana and the climatic factors were established. We analyzed the change rule of radial growth and its relationship with the climatic factors along with the altitude and slope. The results showed that the radial growth of P. massoniana was significantly affected by precipitation and temperature across the altitude gradient and the slope level, respectively. Among the 120 climatic variables, precipitation in December of last year and the extreme minimum temperature in February of current year had the most significant negative effects on the radial growth at different altitudes and slopes, respectively. This study quantitatively described the impacts of climate change on the radial growth of P. massoniana in the subtropical region, and provided a scientific basis for the planting and management of P. massoniana forest in Jiangle Country under the climate warming background.


Assuntos
Mudança Climática , Pinus/crescimento & desenvolvimento , Altitude , Florestas , Temperatura Ambiente , Árvores
6.
Curr Pharm Biotechnol ; 20(15): 1281-1287, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31424365

RESUMO

Pinus species are amongst the most commonly used medicinal plants in Indian Northwestern Himalayas. Nearly all parts of the plant especially needles are believed to possess medicinal and clinical values in traditional systems of medicine such as Ayurvedic, Unani or Homeopathic. They are used to heal numerous diseases, including afflictions of the skin, eyes, throats and ears. Various parts of the plant including needles are rich in biologically active compounds, such as thunbergol, 3-carene, cembrene, α-pinene, quercetin, xanthone, etc. The scientific data available for the biological potential of this plant and its constituents have been found to be scanty and also does not satisfy the basis of their age-old folklore and local uses. This review focuses on a detailed analysis of ethnopharmacognosical studies on the needles of different Pinus species growing naturally in northwestern region of Indian Himalayas including investigations and findings that have come up with a concrete view of the abilities of plant components for example phenolics, flavonoids, tannins and other constituents to treat oxidative, inflammatory and microbial responses. Careful evaluation of the data presented may be helpful for the researchers to discover and evaluate the specific chemical entities responsible for the traditional medicinal uses of P. roxburghii, P.wallichiana, P. merkusii, P.kesiya and P.thunbergii.


Assuntos
Pinus , Extratos Vegetais/farmacologia , Plantas Medicinais , Altitude , Etnobotânica , Flavonoides/isolamento & purificação , Humanos , Índia , Fenóis/isolamento & purificação , Fitoterapia , Pinus/química , Pinus/crescimento & desenvolvimento , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Folhas de Planta/crescimento & desenvolvimento , Plantas Medicinais/química , Plantas Medicinais/crescimento & desenvolvimento , Especificidade da Espécie , Taninos/isolamento & purificação
7.
PLoS One ; 14(7): e0219620, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31295314

RESUMO

Continuity in forest habitats is crucial for species diversity and richness. Ancient Scots pine forests are usually under forest management, which disturbs vegetation and causes differentiation in terms of tree stand age. To date, vegetation variability in ancient Scots pine forests has not been examined based on tree stand age classes. In the present study the continuity of a large Scots pine forest complex was investigated, and a system of sampling plots established in five tree stand age classes: initiation stands (4-10 years), young stands (20-35 years), middle-aged stands (45-60 years), pre-mature stands (70-85 years) and mature stands (95-110 years). Species composition, including vascular plants, bryophytes and lichens, on soil, tree trunks, and coarse woody debris, was analyzed. Based on existing classifications systems, forest species and ancient forest species groups were distinguished. In the studied ancient Scots pine forests the species pool and richness were relatively low, and the vegetation consisted mostly of generalist species. Cryptogams, which can grow on diverse substrates, were the most abundant species. Moreover, most species could tolerate both forest and non-forest conditions. Age class forests provided different environmental niches for species. Initiation stands were optimal for terrestrial light-demanding species, and in terms of species composition, initiation stands were most specific. Young stands were most preferred by species on coarse woody debris, and at this stage of stand maturation epiphytic species re-appeared. The oldest stands were not rich in forest specialists, i.e. species of closed forest and ancient forest species. Cryptogams of closed forests inhabited different substrates, and they were not associated only with the oldest stands. The low number of forest specialists in the oldest stands may be a general feature of acidophilus pine forests. However, it may also be a result of the lack of species sources in the vicinity of maturing pine stands. In managed forests a frequent diversity pattern is an increase in a species pool and richness after clear-cut logging. In the present study we obtained higher species pools in initiation and young stands, but richness was similar in all tree stand age classes. This resulted from taking into account species of different substrates (terrestrial, epixylous and epiphytic species) which changed their participation in the vegetation of subsequent stages of tree stand development.


Assuntos
Biodiversidade , Pinus sylvestris/crescimento & desenvolvimento , Pinus/crescimento & desenvolvimento , Microbiologia do Solo , Briófitas/classificação , Briófitas/crescimento & desenvolvimento , Ecossistema , Florestas , Líquens/classificação , Líquens/crescimento & desenvolvimento , Pinus/microbiologia , Pinus sylvestris/microbiologia , Especificidade da Espécie , Traqueófitas/classificação , Traqueófitas/crescimento & desenvolvimento
8.
Mycorrhiza ; 29(5): 519-530, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31342139

RESUMO

Yellow chanterelles are among the most popular wild edible ectomycorrhizal mushrooms worldwide. The representative European golden chanterelle, Cantharellus cibarius, has only once been reported to fruit under greenhouse conditions, due to the difficulty of establishing pure culture. Recently, we developed a new technique for establishing a pure culture of a Japanese golden chanterelle (Cantharellus anzutake), and conducted in vitro ectomycorrhizal synthesis using established strains and Pinus densiflora. Acclimated pine mycorrhizal seedlings colonized with C. anzutake in a pot system under laboratory conditions produced small but distinct basidiomata with developed basidiospores. C. anzutake mycorrhizae were established on Quercus serrata seedlings by inoculation of mycorrhizal root tips of the fungus synthesized on P. densiflora. A scaled-up C. anzutake-host system in larger pots (4 L soil volume) exhibited repeated fruiting at 20-24 °C under continuous light illumination at 150 µmol m-2 s-1 during a 2-year incubation period. Therefore, a C. anzutake cultivation trial is practical under controlled environmental conditions.


Assuntos
Basidiomycota/fisiologia , Micorrizas/fisiologia , Pinus/microbiologia , Japão , Pinus/crescimento & desenvolvimento , Reprodução , Plântula/crescimento & desenvolvimento , Plântula/microbiologia
9.
Environ Monit Assess ; 191(8): 495, 2019 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-31302796

RESUMO

Benefiting from current unmanned air vehicle (UAV) and remote sensing techniques, the present study aims to estimate tree count (TC), tree height (TH), and tree crown cover area (TCCA) in a young Calabrian pine stand via canopy height model (CHM). Overlay images obtained using Quadcopter were used to generate two spatial three-dimensional (3D) cloud points in two different qualities. Point clouds were processed using R program in order to produce tree data using CHM. The sensitivity of CHM-based tree data was revealed using 318 tree measurements in 32 different sampling units. Estimation and measurement values were classified based on their structure from motion (SfM) quality and cover classes, and the statistical relationships among them were analyzed. Without any classification, R2 was calculated for TC, THMean, and TCCATotal estimations and field measurements. R2 values were calculated as 0.865, 0.778, and 0.869, respectively, for SfMHighest CHM, while they were calculated as 0.863, 0.736, and 0.843, respectively, for SfMMedium CHM. In addition, sensitivity and performance ranking in different groups were determined based on root mean square error (RMSE) and mean absolute percentage error (MAPE) values. A significant difference was observed among groups in terms of quality and cover for TH, while no significant differences were observed for TCCA. Therefore, it is possible to estimate the properties of SfM CHM-based young coniferous stand. It was understood that tree density, crown shape, and branching influenced the accuracy of the present study. The developed UAV (Drone)-SfM is a promising technique for further small-scale forestry studies.


Assuntos
Monitoramento Ambiental/métodos , Agricultura Florestal/métodos , Florestas , Pinus/crescimento & desenvolvimento , Tecnologia de Sensoriamento Remoto , Árvores/crescimento & desenvolvimento , Algoritmos , Processamento de Imagem Assistida por Computador , Análise Espacial , Turquia
10.
Exp Appl Acarol ; 78(4): 469-483, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31338692

RESUMO

The species composition of arboreal oribatid mites that live on Siberian pine trees (Pinus sibirica) in the forest-tundra of Western Siberia was examined, specifically of three Siberian pines from two distinct forest stands (six trees in total). Samples of litter were taken near the tree trunk, as well as samples of bark, branches and needles from the tree. In total 144 samples were taken, from which close to 5000 mites were extracted. From the arboreal samples, the mites were extract by heptane flotation. Three species of oribatid mites were recorded for the first time in Russia: Diapterobates brevidentatus, Eueremaeus trionus and Cultroribula berolina. The highest density and the highest dominance index of these species were recorded in arboreal microhabitats. Thirty-one species of oribatid mites were identified in total. No oribatid mites were recovered from the needles of Siberian pine. The density of oribatid mites did not significantly differ among various heights of the crown and trunk. The lowest density of mites was recorded on young branches without needles, whereas other branch hypothetical microhabitats did not significantly differ from each other in terms of oribatid density. The greatest Simpson diversity index was recorded in the plant litter near tree trunks. On trees, the diversity index decreased with the height of the trunk and with the distance of branch sections from the trunk. The dominant species and the degree of their dominance varied among microhabitats and forest stands. Additionally, a high level of dominance of a single oribatid species was observed on tree branches, as well as on the trunk bark located above the bole. In the two forest stands, these species were D. brevidentatus and Ameronothrus dubinini. Based on the analysis of oribatid communities, three microhabitats were identified in the first forest stand: the bole bark, the bark of the trunk above the bole, and the branches. In the second forest stand, bases of tree branches were identified as an additional microhabitat. Oribatids inhabit Siberian pine trees in the severe conditions of the forest-tundra. Arboreal oribatid communities of various microhabitats vary in their qualitative and quantitative characteristics. Also, arboreal and forest litter communities of oribatid mites vary significantly.


Assuntos
Distribuição Animal , Ecossistema , Ácaros/fisiologia , Pinus , Animais , Biodiversidade , Pinus/crescimento & desenvolvimento , Densidade Demográfica , Sibéria
11.
Sci Total Environ ; 685: 963-975, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31247442

RESUMO

Global change potentially increases forest vulnerability. Different abiotic and biotic factors may interact to cause forest decline and accelerated tree mortality. We studied a mixed Mediterranean continental forest where Pinus pinaster Ait. (maritime pine) shows widespread decline to analyse the role of different abiotic and biotic factors on health status and growth dynamics both at the individual and plot levels. We also analysed stand composition and regeneration of tree species to check whether there is a change in species dominance. Fungal pathogens were seldom present and we detected no pervasive fungi or insect infestation and no presence of pathogens like Heterobasidion or Phytophthora. Infection of hemiparasite plants like Viscum album L. (mistletoe) can reduce leaf area and its abundance is generally considered an expression of host decline. Yet, the existence among declining trees of high defoliation levels without mistletoe, but not vice versa, suggests that defoliation in response to some abiotic stressor could be a predisposing factor preceding mistletoe infection. Compared to healthy trees, declining and dead trees exhibited higher defoliation rates, smaller needles and lower recent growth with steeper negative trends. Dead and declining trees showed similar negative growth trends since the early 1990s droughts, which we interpreted as early warning signals anticipating mortality of currently declining trees in the near future. Mortality of maritime pine extending across all size classes, the lower presence of this species in the smallest size classes and its lack of regeneration suggest it is potentially losing its current dominance and being replaced by other co-occurring, more drought-tolerant species. Our results unravelled that maritime pine decline seems to be mainly driven by a combination of predisposing and inciting abiotic factors (microenvironment and drought stress) and biotic factors (mistletoe). The absence of widespread fungal pathogens suggests that they may have a minor role on pine decline acting only eventually as contributing factors. Although there could be other interrelations among factors or other biotic agents at play, our results strongly suggest that water stress plays a major role in the decline process of the dominant species on an ecosystem with strong land-use legacies.


Assuntos
Florestas , Pinus/fisiologia , Monitoramento Ambiental , Pinus/crescimento & desenvolvimento , Estresse Fisiológico
12.
Biotech Histochem ; 94(7): 546-553, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31045451

RESUMO

Pinus massoniana is a recalcitrant tree species for rooting in vitro. We rejuvenated 26-year-old P. massoniana trees by successive grafting. Rooting rates of rejuvenated shoots were > 83.1% after rooting induction. We compared endogenous levels of indole-3-acetic acid (IAA), abscisic acid (ABA), gibberellins (GAs) and zeatin-riboside (ZR), and the rhizogenesis ability of axillary shoots of mature and rejuvenated materials in vitro, i.e., somaplants and grafts. Enhancement of the rooting ability of mature materials in vitro following somatic embryogenesis or repeated grafting onto juvenile rootstocks was accompanied by increased IAA and GAs levels, and by decreased ABA levels in scions used as starting material for micropropagation in vitro. Successive subcultures did not influence the rooting ability of shoots from untreated mature material. Rooting ability of shoots in vitro, however, gradually increased with subculture frequency during repeated subculturing in grafting materials. The IAA:ABA ratio in shoots in vitro after grafting five times, and consequently capable of root organogenesis, was higher than in shoots of untreated mature material incapable of root organogenesis in vitro. A high IAA:ABA ratio was detected in scions of somaplants that were capable of rooting in vitro despite subculture times. We found that the endogenous IAA:ABA ratio is a reliable marker for the recovery of root organogenesis in vitro after rejuvenating treatments for mature P. massoniana trees.


Assuntos
Ácidos Indolacéticos/farmacologia , Pinus/crescimento & desenvolvimento , Raízes de Plantas/efeitos dos fármacos , Árvores/efeitos dos fármacos , Ácido Abscísico/farmacologia , Isopenteniladenosina/análogos & derivados , Isopenteniladenosina/farmacologia , Pinus/efeitos dos fármacos , Rejuvenescimento/fisiologia
13.
Environ Sci Pollut Res Int ; 26(19): 19365-19378, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31073835

RESUMO

As two main factors, soil and vegetation play key roles in land rehabilitation and ecological remediation of mining areas. There is a complex interaction between soil and vegetation, and understanding the mechanisms of interaction between soil and vegetation is of great significance for land rehabilitation and ecological remediation in mining areas. This study introduced complex network method to analyze the complex interaction systematically. A survey of vegetation and soil properties in 70 reclaimed plots was carried out in the Anjialing and Antaibao opencast coal-mines in Shanxi, China. The indices of soil and vegetation acted as nodes, and the interaction between these indices as sides to establish a soil-vegetation network. Calculating the network indices to analyze the structure of a complex network and explore the mechanism of interaction between soil and vegetation. SOM (soil organic matter) was at the core of the soil-vegetation interaction network. The average path length of the soil-vegetation network was 1.8, with a faster rate of information transfer. The soil-vegetation network consisted of three clusters (soil physical property cluster, soil chemical property cluster, and vegetation cluster), in which the soil chemical property cluster owned the highest clustering coefficient and the largest number of triangles, and it was most stable and the interaction within the cluster was strongest. The soil-vegetation network was stable and the connectivity of the network had robustness to node failures. The scale of the network became larger and the network became tighter and more stable with the increase of reclamation time. Some measures should be conducted to promote vegetation restoration by improving important soil nodes, e.g., surface soil covering, applying organic fertilizer, and planting nitrogen-fixing plants.


Assuntos
Minas de Carvão , Poluição Ambiental/prevenção & controle , Recuperação e Remediação Ambiental/métodos , Pinus/crescimento & desenvolvimento , Solo/química , Ulmus/crescimento & desenvolvimento , China , Fixação de Nitrogênio
14.
Environ Monit Assess ; 191(5): 312, 2019 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-31030271

RESUMO

The study was conducted in dune restoration sites introduced with maritime pine (MP, Pinus pinaster Aiton) and stone pine (SP, Pinus pinea L.) at different development stages (diameters at breast height (DBH) in which small-diameter forests (SDF) = 0-8 cm, medium-diameter forests (MDF) = 8-20 cm, large-diameter forests (LDF) = 20-36 cm, and upper large-diameter forests (UDF) = > 36 cm). There were 15 replicated plots in each stage of both species and 25 dune sites; thus, a total of 145 sample plots were selected. Soil samples were taken from six different depth layers (0-5, 5-15, 15-30, 30-50, 50-70, and 70-100 cm). Forest floors were sampled with five replicates in each plot, and they were separated into leaf + fermentation and humus layers to determine unit mass and carbon concentration. Forest floor mass is significantly increased (17-34 t/ha in MP and 28-57 t/ha in SP) with the development stage. Low organic carbon (0.09-0.36% in MP and 0.13-0.84% in SP) was found in the top soil layer despite a significant accumulation of forest floor. The soil organic carbon density varies between 3 and 34 t C/ha. As the stand development stage increases, clay concentrations in every depth layer increased and soil pH and calcium carbonate values tend to decrease. Results indicated that both species have capability to grow on sandy material within poor nutrient and water capacities in a 50-year restoration process. However, the accumulation of forest floor increased and organic matter storage in the topsoil (0-5 cm) remained quite low due to the slow decomposition process.


Assuntos
Argila/química , Monitoramento Ambiental , Recuperação e Remediação Ambiental , Compostos Orgânicos/análise , Pinus/química , Solo/química , Carbono/análise , Florestas , Pinus/crescimento & desenvolvimento , Folhas de Planta/química , Turquia , Água
15.
Antonie Van Leeuwenhoek ; 112(9): 1341-1348, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30997587

RESUMO

A novel Gram-staining negative, yellow-pigmented, non-motile, aerobic and rod-shaped bacterium, designated MAH-11T, was isolated from rhizosphere of Pinus koraiensis and was characterised by using a polyphasic taxonomic approach. The colonies were smooth, circular and 0.3-1.0 mm in diameter when grown on R2A agar for 3 days. The strain was positive for both catalase and oxidase tests. Optimum growth temperature and pH were 28-30 °C and 7.0, respectively. Cell growth occurs on R2A agar, nutrient agar, Luria-Bertani agar and tryptone soya agar but not on MacConkey agar. The novel strain was found to be able to hydrolyse esculin but not casein, gelatin, starch, L-tyrosine, DNA, L-arginine, urea, Tween 20 and Tween 80. On the basis of 16S rRNA gene sequence analysis, strain MAH-11T belongs to the genus Sphingobium and is closely related to Sphingobium quisquiliarum P25T (98.1%), Sphingobium vermicomposti VC-230T (97.8%), Sphingobium mellinum WI4T (97.5%), Sphingobium barthaii KK22T (97.2%) and Sphingobium fuliginis TKPT (97.2%). In DNA-DNA hybridization tests, the DNA relatedness values between strain MAH-11T and its close phylogenetic neighbors were below 45.0%. The DNA G+C content was 64.5 mol% and the predominant respiratory quinone was identified as ubiquinone-10. The major cellular fatty acids were summed feature 8 (C18:1ω7c and/or C18:1ω6c), summed feature 3 (C16:1ω7c and/or C16:1ω6c) and C16:0. The DNA-DNA hybridization results in combination with chemotaxonomic and physiological data demonstrated that strain MAH-11T represents a novel species within the genus Sphingobium, for which the name Sphingobium chungangianum is proposed. The type strain is MAH-11T (= KACC 19836T = CGMCC 1.13749T).


Assuntos
Pinus/crescimento & desenvolvimento , Microbiologia do Solo , Sphingomonadaceae/classificação , Sphingomonadaceae/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Análise por Conglomerados , Citosol/química , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Hibridização de Ácido Nucleico , Filogenia , Quinonas/análise , RNA Ribossômico 16S/genética , Rizosfera , Análise de Sequência de DNA , Sphingomonadaceae/genética , Sphingomonadaceae/fisiologia
16.
Sensors (Basel) ; 19(7)2019 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-30935004

RESUMO

A data set of very high-resolution visible/near infrared hyperspectral images of young Pinus contorta trees was recorded to study the effects of herbicides on this invasive species. The camera was fixed on a frame while the potted trees were moved underneath on a conveyor belt. To account for changing illumination conditions, a white reference bar was included at the edge of each image line. Conventional preprocessing of the images, i.e., dividing measured values by values from the white reference bar in the same image line, failed and resulted in bad quality spectra with oscillation patterns that are most likely due to wavelength shifts across the sensor's field of view (smile effect). An additional hyperspectral data set of a Spectralon white reference panel could be used to characterize and correct the oscillations introduced by the division, resulting in a high quality spectra that document the effects of herbicides on the reflectance characteristics of coniferous trees. While the spectra of untreated trees remained constant over time, there were clear temporal changes in the spectra of trees treated with both herbicides. One herbicide worked within days, the other one within weeks. Ground-based imaging spectroscopy with meaningful preprocessing proved to be an appropriate tool for monitoring the effects of herbicides on potted plants.


Assuntos
Fotografação/métodos , Pinus/crescimento & desenvolvimento , Espectroscopia de Luz Próxima ao Infravermelho , Herbicidas , Processamento de Imagem Assistida por Computador , Espécies Introduzidas
17.
Tree Physiol ; 39(6): 983-999, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30976807

RESUMO

Altitudinally separated bristlecone pine populations in the White Mountains (California, USA) exhibit differential climate-growth responses as temperature and tree-water relations change with altitude. These populations provide a natural experiment to explore the ecophysiological adaptations of this unique tree species to the twentieth century climate variability. We developed absolutely dated annual ring-width chronologies, and cellulose stable carbon and oxygen isotope chronologies from bristlecone pine growing at the treeline (~3500 m) and ~200 m below for the period AD 1710-2010. These chronologies were interpreted in terms of ecophysiological adaptations to climate variability with a dual-isotope model and a leaf gas exchange model. Ring widths show positive tree growth anomalies at treeline and consistent slower growth below treeline in relation to the twentieth century warming and associated atmospheric drying until the 1980s. Growth rates of both populations declined during and after the 1980s when growing-season temperature and atmospheric vapour pressure deficit continued to increase. Our model-based interpretations of the cellulose stable isotopes indicate that positive treeline growth anomalies prior to the 1980s were related to increased stomatal conductance and leaf-level transpiration and photosynthesis. Reduced growth since the 1980s occurred with a shift to more conservative leaf gas exchange in both the treeline and below-treeline populations, whereas leaf-level photosynthesis continued to increase in response to rising atmospheric CO2 concentrations. Our results suggest that warming-induced atmospheric drying confounds positive growth responses of apparent temperature-limited bristlecone pine populations at treeline. In addition, the observed ecophysiological responses of attitudinally separated bristlecone pine populations illustrate the sensitivity of conifers to climate change.


Assuntos
Isótopos de Carbono/análise , Mudança Climática , Dessecação , Isótopos de Oxigênio/análise , Pinus/crescimento & desenvolvimento , Árvores/crescimento & desenvolvimento , Altitude , California , Pinus/química , Temperatura Ambiente , Árvores/química , Madeira/química
18.
Mycorrhiza ; 29(3): 207-218, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30953171

RESUMO

Forest trees are colonised by different species of ectomycorrhizal (ECM) fungi that interact competitively or mutualistically with one another. Most ECM fungi can produce sporocarps. To date, the effects of co-colonising fungal species on sporocarp formation in ECM fungi remain unknown. In this study, we examined host plant growth, mycorrhizal colonisation, and sporocarp formation when roots of Pinus densiflora are colonised by Laccaria japonica and three other ECM fungal species (Cenococcum geophilum, Pisolithus sp., and Suillus luteus). Sporocarp numbers were recorded throughout the experimental period. The biomass, photosynthetic rate, and mycorrhizal colonisation rate of the seedlings were also measured at 45 days, 62 days, and 1 year after seedlings were transplanted. Results indicated that C. geophilum and S. luteus may negatively impact mycorrhizal colonisation and sporocarp formation in L. japonica. Sporocarp formation in L. japonica was positively correlated with conspecific mycorrhizal colonisation but negatively correlated with the biomass of seedlings of P. densiflora. The co-occurring ECM fungi largely competed with L. japonica, resulting in various effects on mycorrhizal colonisation and sporocarp formation in L. japonica. A variety of mechanisms may be involved in the competitive interactions among the different ECM fungal species, including abilities to more rapidly colonise root tips, acquire soil nutrients, or produce antibiotics. These mechanisms need to be confirmed in further studies.


Assuntos
Laccaria/fisiologia , Micorrizas/fisiologia , Pinus/microbiologia , Plântula/microbiologia , Biomassa , Florestas , Laccaria/crescimento & desenvolvimento , Micorrizas/crescimento & desenvolvimento , Pinus/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Árvores/microbiologia
19.
Chemosphere ; 224: 862-872, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30852466

RESUMO

Ectomycorrhizal (ECM) fungi can improve the growth of pine trees and enhance their tolerance to heavy metal stress, and may also be useful during the afforestation and phytoremediation of polluted regions with pine trees. Hebeloma vinosophyllum (Cr(VI)-sensitive strain) and Pisolithus sp1 ((Cr(VI)-tolerant strain) were selected through liquid culture experiment, and were used in symbiosis with Japanese black pine (Pinus thunbergii) in pot experiments, to determine their potential for improving phytoremediation of Cr(VI)-contaminated soils. Our results indicated that Pisolithus sp1 also had a significantly higher accumulation of Cr than H. vinosophyllum in mycelium under the same Cr(VI) treatments in liquid culture experiment. The tolerance index of Pisolithus sp1 ECM seedlings' shoots and roots to Cr(VI) were significantly higher than that of H. vinosophyllum ECM and non-ectomycorrhizal (NM) seedlings while the total accumulated Cr per seedling in Pisolithus sp1 ECM seedlings were 1.50-1.96 and 2.83-27.75 fold higher that of H. vinosophyllum ECM and NM seedlings, respectively, within 0-800 mg kg-1 Cr(VI) treatments in pot experiments. In addition, the significant differences ratios of photosynthetic rate, stomatal conductance, transpiration rate and intercellular CO2 concentration between Pisolithus sp1 ECM and NM seedlings were significantly higher than those between H. vinosophyllum ECM and NM seedlings under 400 and 800 mg kg-1 Cr(VI) treatments. Compared with the control (no plant), and planting NM or H. vinosophyllum ECM seedlings, the planting of Pisolithus sp1 ECM seedlings significantly reduced the percentage content of exchangeable Cr in the soil.


Assuntos
Biodegradação Ambiental , Cromo/metabolismo , Hebeloma/metabolismo , Micorrizas/metabolismo , Pinus/crescimento & desenvolvimento , Cromo/análise , Micélio/química , Raízes de Plantas/microbiologia , Plântula/crescimento & desenvolvimento , Solo/química
20.
PLoS One ; 14(3): e0213509, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30856232

RESUMO

Tree height growth is sensitive to climate change; therefore, incorporating climate factors into tree height prediction models can improve our understanding of this relationship and provide a scientific basis for plantation management under climate change conditions. Mongolian pine (Pinus sylvestris var. mongolica) is one of the most important afforestation species in Three-North Regions in China. Yet our knowledge on the relationship between height growth and climate for Mongolian pine is limited. Based on survey data for the dominant height of Mongolian pine and climate data from meteorological station, a mixed-effects Chapman-Richards model (including climate factors and random parameters) was used to study the effects of climate factors on the height growth of Mongolian pine in Zhanggutai sandy land, Northeast China. The results showed that precipitation had a delayed effect on the tree height growth. Generally, tree heights increased with increasing mean temperature in May and precipitation from October to April and decreased with increasing precipitation in the previous growing season. The model could effectively predict the dominant height growth of Mongolian pine under varying climate, which could help in further understanding the relationship between climate and height growth of Mongolian pine in semiarid areas of China.


Assuntos
Pinus/crescimento & desenvolvimento , China , Clima , Mudança Climática , Florestas , Modelos Biológicos , Pinus sylvestris/crescimento & desenvolvimento , Tempo (Meteorologia)
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