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1.
Bioresour Technol ; 341: 125862, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34523580

RESUMO

Multistage fractionation of pine bark was performed using subcritical and supercritical CO2 at increasing pressures and temperatures. In total, seven fractions were collected, which demonstrated different enrichments of families of compounds. In particular, subcritical CO2 yielded 41% of the total extract in which unsaturated fatty acids represented the most abundant family. The subsequent five supercritical steps increased the recovery of sterol esters, wax esters and resin acids at higher temperatures and pressures, reaching 80% of the total extractable mass. In the last step, using ethanol as a co-solvent, an additional 20% of extract was recovered, which was enriched with phenolics and glycerol. A full characterisation of the extracts was accomplished by high-temperature GC-MS/FID using four internal standards, which were representative of the main classes of compounds contained in the pine bark extract.


Assuntos
Cromatografia com Fluido Supercrítico , Pinus , Dióxido de Carbono , Fracionamento Químico , Casca de Planta , Solventes
2.
Environ Monit Assess ; 193(10): 630, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34490554

RESUMO

Soil carbon dioxide emission is a major component of ecosystem respiration, responsible for organic carbon losses from the ecosystem. In Pinus roxburghii Sarg. plantations, higher CO2 emission coincided with maximum soil moisture and soil temperature during the rainy season (4.23 µmol CO2m-2 s-1) followed by summer season (1.69 µmol CO2m-2 s-1) and winter season (1.35 µmol CO2m-2 s-1). The soil CO2 emission rates recorded during the rainy season differed significantly from other seasons (p < 0.05). Multiple linear regression revealed that rainfall was the main dominant factor affecting the soil CO2 emission. A significant positive correlation with minimum air temperature and average air temperature during the lag period, i.e., preceding 15 days of data, was recorded. A significant positive correlation was also observed between annual soil CO2 emission rates with soil temperature, soil moisture, air temperature, and rainfall (p < 0.05). Vapor pressure and relative humidity at 14.19 h also emerged as additional scientific variables affecting soil CO2 emission with significant positive correlations. Annual soil CO2 emission rates and soil properties were not significantly correlated but were positively correlated with organic carbon, exchangeable potassium and negatively correlated with available nitrogen and phosphorous (p > 0.05). Higher annual average carbon stock, 95.05 t ha-1 in P. roxburghii plantations than the yearly soil CO2 emission, 33.23 t ha-1 indicates that plantations sequester more carbon than the emissions.


Assuntos
Pinus , Solo , Carbono , Dióxido de Carbono/análise , China , Ecossistema , Monitoramento Ambiental , Estações do Ano
3.
Chimia (Aarau) ; 75(9): 780-787, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34526184

RESUMO

CST (Crude Sulfate Turpentine) is an upcycled, biomass raw material derived from pinewood, obtained as a by-product of the Kraft process from the pulp and paper industry. The current article provides an overview of major renewable perfumery ingredients obtained from CST-derived alpha- and beta-pinene to-date and part of the Firmenich manufacturing portfolio, post DRT acquisition.


Assuntos
Perfumes , Pinus , Terebintina
4.
Braz J Biol ; 83: e244011, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34468510

RESUMO

Climatic factors play an essential role in the growth of tree ring width. In this study, we aimed to evaluate the correlation between climatic variables and tree-ring growth characteristics of Pinus sibirica in Altai mountains, northwestern China. This study being is first of its kind on climate growth analysis of Pinus sibirica in northwestern China. The study showed great potential to understand the species growing under the specific climatic conditions. Total of 70 tree cores collected from three sites in the sampling area, out of which 63 tree cores considered for this study. The effect of climatic variables which was studied include precipitation, temperature and PDSI. Our results showed that Tree Ring Width chronology has a significantly positive correlation with the late winter (March) temperature and significant negative correlation with the July temperatures. A significant correlation was observed with the late summer precipitation whereas no significant relation found with the Palmer Drought Severity Index. These significant correlations with temperature and precipitation suggested that this tree species had the potential for the reconstruction of the past climate in the area.


Assuntos
Pinus , China , Secas , Temperatura , Árvores
5.
Environ Monit Assess ; 193(9): 621, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34476631

RESUMO

Global acreage of forested lands has increased in some countries. At least some of this increase is due to the natural conversion of abandoned agricultural lands into forests. However, little is known about how these new stands develop on abandoned agricultural lands in comparison with natural regeneration of existing forests. Specifically, knowledge of how black pine (Pinus nigra Arnold) naturally establishes and develops on abandoned agricultural lands is limited. In this study, we examined the density and growth of black pine saplings as well as some morphological and anatomical characteristics on an abandoned agricultural land (AAS). These data were compared with those observed in a naturally regenerated stand (NRS), and in a forest opening (FOS). The greatest sapling density was observed in the NRS site, while sapling growth and stem biomass were higher in AAS followed by NRS and FOS. Moreover, each study site exhibited site-specific morphological and anatomical traits in their saplings. Our findings showed that site treatments and overstory openness would both play crucial role for establishment and development of black pine.


Assuntos
Monitoramento Ambiental , Pinus , Agricultura , Biomassa , Florestas , Árvores
6.
Sci Total Environ ; 798: 149308, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34375257

RESUMO

Fire and drought are two major agents that shape Mediterranean ecosystems, but their interacting effects on forest resilience have not been yet fully addressed. We used Pinus halepensis to investigate how compound fire-drought regimes determine the success of post-fire regeneration. We measured the density of P.halepensis newly established individuals following fire in forty-three sites along the Spanish east coast, the wetter region of the species distribution. The climatic niche of P.halepensis was characterized by considering their populations across its Spanish distribution range. We used yearly values (1979-2013 period) of accumulated precipitation, mean temperature and the warmest quarter values of these two variables to generate the climatic space or climatic niche occupied by the species. Kernel density estimates were then applied to determine the niche centroid, which would correspond to the species' climatic optimum within its Spanish distribution range. Then, we computed the pre- and post-fire climatic deviations of each sampling site as the difference between site-specific climate conditions respect to the species niche centroid, and assessed their relationship with the success of post-fire regeneration. We found highly variable patterns of post-fire regeneration density of P.halepensis over the studied sites, ranging from 7 to 42,822 tree pines ha-1. Generalized linear models indicated a positive relationship between fire severity and the density of P.halepensis regeneration. Positive temperature deviations - warm conditions - before fire were positively related to pine regeneration. This effect increases under higher fire severity. By contrast, warm temperatures after fire showed a negative effect on the density of pine trees. Positive precipitation deviations - wet conditions - after fire enhanced pine regeneration, while precipitation before fire did not had any significant effect. Though P.halepensis is considered a species adapted to fire and drought, the interaction between these two disturbances can alter the success of its post-fire recovery patterns limiting the species' resilience in the future.


Assuntos
Incêndios , Pinus , Secas , Ecossistema , Florestas , Humanos , Espanha , Árvores
7.
Sci Total Environ ; 796: 148930, 2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34378542

RESUMO

Forests are being impacted by climate and land-use changes which have altered their productivity and growth. Understanding how tree growth responds to climate in natural and planted stands may provide valuable information to prepare management in sight of climate change. Plantations are expected to show higher sensitivity to climate and lower post-drought resilience than natural stands, due to their lower compositional and structural diversity. We reconstructed and compared the radial growth of six conifers with contrasting ecological and climatic niches (Abies pinsapo, Cedrus atlantica, Pinus sylvestris, Pinus nigra, Pinus pinea, Pinus pinaster) in natural and planted stands subjected to seasonal drought in 40 sites. We quantified the relationships between individual growth variability and climate variables (temperature, precipitation and the SPEI drought index), as well as post-drought resilience. Elevated precipitation during the previous autumn-winter and current spring to early summer enhanced growth in both natural and planted stands of all species. Temperature effects on growth were less consistent: only plantations of A. pinsapo, C. atlantica, P. nigra, P. pinea, P. sylvetris and a natural stand of P. nigra showed negative impacts of summer temperature on growth. Drought reduced growth of all species in both plantations and natural stands, with variations in the temporal scale of the response. Drought constrained growth more severely in natural stands than in plantations of C. atlantica, P. pinaster and P. nigra, whereas the inverse pattern was found for A. pinsapo. Resilience to drought varied between species: natural stands of A. pinsapo, C. atlantica and P. pinaster recovered faster than plantations, while P. pinea plantations recovered faster than natural stands. Overall, plantations did not consistently show a higher sensitivity to climate and a lower capacity to recover after drought. Therefore, plantations are potential tools for mitigating climate warming.


Assuntos
Pinus , Traqueófitas , Mudança Climática , Secas , Florestas , Temperatura , Árvores
8.
Phytother Res ; 35(9): 5178-5188, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34382717

RESUMO

Inflammation plays an important role in the pathophysiology of traumatic brain injury (TBI). Based on the anti-inflammatory properties of French maritime pine bark extract and the neuroprotective effects, we aimed to evaluate the effects of its supplementation on TBI. Sixty-seven TBI patients admitted to the intensive care units (ICUs) were enrolled. After stabilizing the hemodynamic status, the intervention group received 150 mg of French maritime pine bark extract supplementation (Oligopin) with enteral nutrition for 10 days. The control group received a placebo. Inflammatory status and oxidative stress markers were measured three times. Also, clinical and nutritional statuses were assessed. Supplementation, significantly decreased IL-6 (ß = -53.43 pg/ml, 95% confidence interval [CI] = -91.74, -15.13, p = .006), IL-1ß (ß = -111.66 pg/ml, 95% CI = -183.79, -39.5402, p = .002) and C-reactive protein (ß = -19.99 mg/L, 95% CI = -27.23, -12.76, p Ëƒ .001) in the intervention group compared to control group after 10 days. Clinical scores including acute physiology and chronic health evaluation II and sequential organ failure assessment were reduced (ß = -3.72, 95% CI = -5.96, -1.49, p = .001and ß = -2.07, 95% CI = -3.23, -0.90, p < .001, respectively), and Nutric score was reduced compared to control group (ß = -.60, 95% CI = -1.08, -0.12, p = .01). The survival rate was higher by 15% in the intervention group compared to control group. Oligopin supplementation in TBI patients in ICU reduced inflammation and improved the clinical status and malnutrition score and thereby reducing the mortality rate.


Assuntos
Lesões Encefálicas Traumáticas , Flavonoides/uso terapêutico , Pinus/química , Extratos Vegetais/uso terapêutico , Lesões Encefálicas Traumáticas/tratamento farmacológico , Estado Terminal , Suplementos Nutricionais , Humanos , Inflamação/tratamento farmacológico , Estado Nutricional , Casca de Planta/química
9.
J Plant Physiol ; 265: 153489, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34416600

RESUMO

Down-regulation of photosynthesis under elevated CO2 (eCO2) concentrations could be attributed to the depletion of nitrogen (N) availability after long-term exposure to eCO2 (progressive nitrogen limitation, PNL) or leaf N dilutions due to excessive accumulation of nonstructural carbohydrates. To determine the mechanism underlying this down-regulation, we investigated N availability, photosynthetic characteristics, and N allocation in leaves of Pinus densiflora (shade-intolerant species, evergreen tree), Fraxinus rhynchophylla (intermediate shade-tolerant species, deciduous tree), and Sorbus alnifolia (shade-tolerant species, deciduous tree). The three species were grown under three different CO2 concentrations in open-top chambers, i.e., ambient 400 ppm (aCO2); ambient × 1.4, 560 ppm (eCO21.4); and ambient × 1.8, 720 ppm (eCO21.8), for 11 years. Unlike previous studies that addressed PNL, after 11 years of eCO2 exposure, N availability remained higher under eCO21.8, and chlorophyll and photosynthetic N use efficiency increased under eCO2. In the case of nonstructural carbohydrates, starch and soluble sugar showed significant increases under eCO2. The maximum carboxylation rate, leaf N per mass (Nmass), and ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) were low under eCO21.8. The ratio of RuBP regeneration to the carboxylation rate as well as that of chlorophyll N to Rubisco N increased with CO2 concentrations. Based on the reduction in Nmass (not in Narea) that was diluted by increase in nonstructural carbohydrate, down-regulation of photosynthesis was found to be caused by the dilution rather than PNL. The greatest increases in chlorophyll under eCO2 were observed in S. alnifolia, which was the most shade-tolerant species. This study could help provide more detailed, mechanistically based processes to explain the down-regulation of photosynthesis by considering two hypotheses together and showed N allocation seems to be flexible against changes in CO2 concentration.


Assuntos
Adaptação Ocular/fisiologia , Dióxido de Carbono/efeitos adversos , Regulação para Baixo/fisiologia , Nitrogênio/metabolismo , Fotossíntese/fisiologia , Folhas de Planta/metabolismo , Fraxinus/fisiologia , Pinus/fisiologia , Ribulose-Bifosfato Carboxilase/metabolismo , Sorbus/fisiologia
10.
Molecules ; 26(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34361744

RESUMO

Korean red pine (Pinus densiflora) belongs to the Genus Pinus, and its bark contains a great amount of naturally occurring phenolic compounds. Until now, few studies have been conducted to assess the neuroprotective effects of Pinus densiflora bark extract against brain ischemic injury. The aim of this study was to investigate the neuroprotective effects of pre-treatment with the extract in the hippocampus following 5-min transient forebrain ischemia in gerbils. Furthermore, this study examined the anti-inflammatory effect as a neuroprotective mechanism of the extract. Pinus densiflora bark was extracted by pure water (100 °C), and this extract was quantitatively analyzed and contained abundant polyphenols, flavonoids, and proanthocyanidins. The extract (25, 50, and 100 mg/kg) was orally administered once a day for seven days before the ischemia. In the gerbil hippocampus, death of the pyramidal neurons was found in the subfield cornu ammonis 1 (CA1) five days after the ischemia. This death was significantly attenuated by pre-treatment with 100 mg/kg, not 25 or 50 mg/kg, of the extract. The treatment with 100 mg/kg of the extract markedly inhibited the activation of microglia (microgliosis) and significantly decreased the expression of pro-inflammatory cytokines (interleukin 1ß and tumor necrosis factor α). In addition, the treatment significantly increased anti-inflammatory cytokines (interleukin 4 and interleukin 13). Taken together, this study clearly indicates that pre-treatment with 100 mg/kg of Pinus densiflora bark extract in gerbils can exert neuroprotection against brain ischemic injury by the attenuation of neuroinflammatory responses.


Assuntos
Anti-Inflamatórios/farmacologia , Isquemia Encefálica/tratamento farmacológico , Hipocampo/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Pinus/química , Prosencéfalo/efeitos dos fármacos , Animais , Anti-Inflamatórios/química , Isquemia Encefálica/genética , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Flavonoides/química , Flavonoides/farmacologia , Expressão Gênica/efeitos dos fármacos , Gerbillinae , Hipocampo/metabolismo , Hipocampo/patologia , Inflamação , Interleucina-13/agonistas , Interleucina-13/genética , Interleucina-13/metabolismo , Interleucina-1beta/antagonistas & inibidores , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Interleucina-4/agonistas , Interleucina-4/genética , Interleucina-4/metabolismo , Masculino , Microglia/efeitos dos fármacos , Microglia/metabolismo , Microglia/patologia , Fármacos Neuroprotetores/química , Casca de Planta/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Polifenóis/química , Polifenóis/farmacologia , Proantocianidinas/química , Proantocianidinas/farmacologia , Prosencéfalo/metabolismo , Prosencéfalo/patologia , Células Piramidais/efeitos dos fármacos , Células Piramidais/metabolismo , Células Piramidais/patologia , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
11.
J Chem Ecol ; 47(8-9): 732-739, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34347234

RESUMO

The pine brown tail moth, Euproctis terminalis (Walker 1855), is a periodic pest in pine plantations in South Africa. The larvae feed on pine needles and can cause severe defoliation when population densities are high. Population densities fluctuate temporally and spatially, complicating the prediction of potential growth loss and tree mortality. The aim of this study was to identify the sex pheromone of the pine brown tail moth to provide stakeholders with a tool for monitoring it. Gas chromatography-electroantennogram detection and gas chromatography/mass spectrometry analyses of female pheromone gland extracts identified the major component as (Z,Z,Z,Z)-7,13,16,19-docosatetraen-1-ol isobutyrate. Traps baited with (Z,Z,Z,Z)-7,13,16,19-docosatetraen-1-ol isobutyrate caught more males than unbaited traps. A delta trap was shown to be a superior design compared to a bucket funnel trap. This pheromone can now be used for monitoring E. terminalis in pine plantations.


Assuntos
Mariposas/fisiologia , Atrativos Sexuais/análise , Animais , DNA/química , Complexo IV da Cadeia de Transporte de Elétrons/genética , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Isobutiratos/análise , Isobutiratos/farmacologia , Larva/crescimento & desenvolvimento , Masculino , Mariposas/química , Mariposas/crescimento & desenvolvimento , Pinus/parasitologia , Análise de Sequência de DNA , Atrativos Sexuais/farmacologia , Comportamento Sexual Animal/efeitos dos fármacos
12.
BMC Plant Biol ; 21(1): 363, 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34376154

RESUMO

BACKGROUND: To meet increasing demand for forest-based products and protect natural forests from further deforestation requires increased productivity from planted forests. Genetic improvement of conifers by traditional breeding is time consuming due to the long juvenile phase and genome complexity. Genetic modification (GM) offers the opportunity to make transformational changes in shorter time frames but is challenged by current genetically modified organism (GMO) regulations. Genome editing, which can be used to generate site-specific mutations, offers the opportunity to rapidly implement targeted improvements and is globally regulated in a less restrictive way than GM technologies. RESULTS: We have demonstrated CRISPR/Cas9 genome editing in P. radiata targeting a single-copy cell wall gene GUX1 in somatic embryogenic tissue and produced plantlets from the edited tissue. We generated biallelic INDELs with an efficiency of 15 % using a single gRNA. 12 % of the transgenic embryogenic tissue was edited when two gRNAs were used and deletions of up to 1.3 kb were identified. However, the regenerated plants did not contain large deletions but had single nucleotide insertions at one of the target sites. We assessed the use of CRISPR/Cas9 ribonucleoproteins (RNPs) for their ability to accomplish DNA-free genome editing in P. radiata. We chose a hybrid approach, with RNPs co-delivered with a plasmid-based selectable marker. A two-gRNA strategy was used which produced an editing efficiency of 33 %, and generated INDELs, including large deletions. Using the RNP approach, deletions found in embryogenic tissue were also present in the plantlets. But, all plants produced using the RNP strategy were monoallelic. CONCLUSIONS: We have demonstrated the generation of biallelic and monoallelic INDELs in the coniferous tree P. radiata with the CRISPR/Cas9 system using plasmid expressed Cas9 gRNA and RNPs respectively. This opens the opportunity to apply genome editing in conifers to rapidly modify key traits of interest.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes/métodos , Genoma de Planta , Pinus/genética , DNA de Plantas , Mutação INDEL , RNA Guia , Ribonucleoproteínas/genética
13.
Sci Total Environ ; 795: 148875, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34247087

RESUMO

Increasing temperature over recent decades is expected to positively impact tree growth in humid regions. However, high stand density could increase the negative effects of warming-induced drought through inter-tree competition. How neighborhood competition impacts tree growth responding to climate change remains unclear. Here, we utilized the Changbai Mountain region in northeastern Asia as our study area. We quantified individual tree growth using tree-ring samples collected from three dominant tree species growing in three forest stand density levels. We estimated the effects of climate warming and forest stand density on growth processes and tested for a species-specific response to climate. Our results demonstrated that overall 25% of Korean pine, but only ~3% of Mongolian oak and ~ 4% of Manchurian ash experienced growth reduction. Increased forest density can also exacerbate growth reduction. We identified a climate turning point in 1984, where warming rapidly increased, and defined two groups, "enhance group" (EG) and "decline group" (DG), according to the individual tree growth trend after 1984. For the EG, climate warming increased temperature sensitivity, but the temperature sensitivity declined with increasing stand density for the whole study period. For the DG, tree growth sensitivity shifted from temperature to precipitation after 1984, driven by increased competition pressure under climate warming. Our study concludes that growth decline from warming-induced drought might be amplified by high forest stand density, was especially pronounced in conifer trees.


Assuntos
Pinus , Traqueófitas , Ásia , Mudança Climática , Florestas , Árvores
14.
Sci Total Environ ; 796: 148952, 2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34274661

RESUMO

Poor reforestation outcomes imply failure to fulfill program goals and tend to erode institutional willpower and political momentum towards reforestation efforts, affecting both public and private support. However, program improvement in real reforestation projects is challenging, due to the conjunction of many different variables that mutually interact and feed back on each other inextricably. This study develops a comprehensive assessment framework for reforestation programs, for which technical and environmental information is gathered and related to indicators of performance in both the short- and mid-term. This assessment, tested on a case study, aimed to provide reliable end-results for survival and growth, revealed pitfalls in successful plantation establishment and taught us how to improve plantation performance and what the margin for this improvement was. The selected project was carried out on harsh site conditions, with different species, cultivation treatments and contractors, and was affected by the driest year on record. Plantation mortality was high and increased progressively over time, particularly in the short-term when the rate was 53% (rising to 83% after ten years), showing high variation between sites and species (Pinus pinaster and Quercus faginea died more than 94% after ten years while Junipus phoenicea only 40%). All the hardwoods and the juniper showed lower growth rate after ten years (average stem volume < 40 cm3) than pines (stem volume > 470 cm3). Technical variables (project planning and execution) had a relatively important impact on plantation performance in the first two years (11-29%), but decreased with time, whilst environmental variables (site and meteorological) were more important ten years after planting (>50%). In the short-term, soil moisture and meteorology during the planting season were identified as key factors that triggered the effects of both technical decisions (planting date and planting technique) and other environmental variables on performance. In the design phase, some decisions related to zoning, species selection and cultural treatments were related to poor performance. The results provide practical information and guidelines about all potential drivers of plantation performance and contribute to identify those aspects more related to success of forest restoration in Mediterranean drylands.


Assuntos
Juniperus , Pinus , Ecossistema , Florestas , Solo , Árvores
15.
Ying Yong Sheng Tai Xue Bao ; 32(7): 2335-2346, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34313050

RESUMO

To understand the effects of 'planting conifer and preserving broadleaved tree' and light-felling on the hydrological effects of litter layer during the restoration of the climax vegetation broad-leaved Korean pine forest in temperate zone of Northeast China, we measured litter accumulation, water holding process of litter, and maximum holding water, maximum blocking and effective blocking amount of litter layers using sample survey method and indoor immersion method in three forests (aspen-Korean pine forests, white birch-Korean pine forest, and Mongolian oak-Korean pine forest) under different light-felling intensity (control, C; low light-felling, L; moderate light-felling, M; heavy light-felling, H) in Xiaoxing'an Mountains. The results showed that the intensity of light-felling had different effects on litter accumulation (7.32 to 15.58 t·hm-2) in three forest types. L, M and H significantly enhanced litter accumulation by 24.3%-34.6% in the Mongolian oak-Korean pine forest, L and M enhance it by 15.3%-19.3% in aspen-Korean pine forest, and H enhance it by 27.1% in white birch-Korean pine forest. Water holding capacity (W) and water absorption rate (V) of the undecomposed layer and the semi-decomposed layer of the litter were in accordance with the relationship between the soaking time (t): W=alnt+b (R2>0.908), V=ktn (R2≥0.999). The intensity of light-felling (except H in aspen-Korean pine forests) increased the maximum water holding capacity (17.86-45.12 t·hm-2), maximum interception capacity (16.10-34.19 t·hm-2) and effective interception capacity (13.42-27.42 t·hm-2) of litter by 30.1%-74.8%, 27.4%-83.6% and 26.7%-86.0%, respectively, while changed the differences of effective blocking amount of litters among forest types. Therefore, light-felling significantly enhanced the hydro-ecological function of litter layers in the medium-term broad-leaved Korean pine forests by 'planting conifer and preserving broadleaved tree'. The low, moderate, and heavy light-felling was best one for the Mongolian oak-Korean pine forest, the aspen-Korean pine forest, and the white birch-Korean pine forest, respectively.


Assuntos
Pinus , Traqueófitas , China , Florestas , República da Coreia , Solo , Árvores
16.
Ying Yong Sheng Tai Xue Bao ; 32(7): 2347-2354, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34313051

RESUMO

The complex terrain and poor climatic conditions in Bashang area of Hebei Province result in water and soil loss and geological disasters, which pose a serious threat to ecological safety in North China. In order to improve local environmental quality, barren-resistant and fast-growing tree species such as Pinus sylvestris var. mongolica and Larix gmelinii are planted with large areas. However, unreasonable plantation density will lead to inefficient utilization of rainfall and intensify the conflict between forest and water. In this study, we analyzed the effects of five thinning intensities (0, 20%, 40%, 60%, 80%) of P. sylvestris var. mongolica plantation on herbs, litter, soil and overall water-holding capacity, with the aim to provide scientific basis for management of P. sylvestris var. mongolica. The results showed that water-holding rate of herb varied from 47.7% to 90.7%, and that the water-holding capacity of herb decreased with increasing thinning intensity. When the thinning intensity was less than 40%, water-holding capacity decreased slowly, and then decreased rapidly. With the increase of thinning intensity, natural water-holding rate and maximum water-holding rate of undecomposed layer and semi-decomposed layer decreased gradually, with the effective water-holding rate being 60%>40%>20%>80%>0, and the water-holding capacity of semi-decomposed layer being better than that of undecomposed layer. The water-holding capacity of soil decreased gradually with the increases of thinning intensity. Thinning intensity less than 40% promoted water holding capacity. Under different thinning intensities, the total water-holding rate of understory was 8.3%-14.3%, with an order of 20%>0>40%>60%>80%. In view of understory all layers and overall changes, the thinning intensity at 20% in the study area could effectively improve the understory water-holding capacity and achieve better ecological benefits.


Assuntos
Pinus sylvestris , Pinus , China , Florestas , Solo , Água/análise
17.
Ying Yong Sheng Tai Xue Bao ; 32(7): 2355-2362, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34313052

RESUMO

Stand density is a critical factor impacting the diversity of understory plants. We analyzed the diversity of understory plants and soil seed banks, as well as their relationship by setting up three planting densities in a Pinus massoniana plantation, including low density (1575 trees·hm-2, D1), medium (2474 trees·hm-2, D2), and high (3550 trees·hm-2, D3). It aimed to provide a scientific basis for the implementation of the multi-objective sustainable development of plantations. The results showed that there were 70 species of herbs and shrubs belonging to 42 families and 62 genera. D1 was dominated by heliophiles, whereas both the D2 and D3 were dominated by shade-tolerant species. The Margalef (M), Shannon (H), Simpson (D), Pielou (Jsw), and Altalo (Al) indices of the herbs and shrubs exhibited a downward trend with increasing stand den-sity. In the herb layer, D1 and D3 showed significant difference in H, D, Jsw and Al. There were significant differences of Jsw and Al in the shrub layer among the three stand densities, but no diffe-rence of H and D. H, D, Jsw and Al in the soil seed bank first decreased and then increased with increasing stand density, with species richness and diversity being the highest in D1. The similarity coefficient of Jaccard and Sorensen among different stand densities was low. In the herb layer, M was positively correlated with Jsw. The correlations between stand density and H, D, Jsw and Al were greater in the shrub layer than in the herb layer. There was significant negative correlation between stand density and Jsw both in the shrub and herb layers. The stand density of 1575 trees·hm-2 was comparatively beneficial for the development of understory, plant diversity, and sustainability of P. massoniana plantation.


Assuntos
Pinus , China , Humanos , Banco de Sementes , Solo , Árvores
18.
Pestic Biochem Physiol ; 177: 104902, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34301363

RESUMO

Bursaphelenchus xylophilus (Pinewood nematode, PWN) is the causative agent of pine wilt disease (PWD) which caused serious threat to pine forests in the world, especially in East Asia and Western Europe. At present, the control of PWD mainly rely on the massive use of pesticide despite the damage to human health and environmental safety. Developing novel drug targets is the optimized strategy for developing new method to control PWN. In this study, four multidrug resistance-associated protein (MRP) genes containing highly conserved MRP-associated domains were cloned from PWN. The expression patterns of the four Bx-mrps under three different nematicides treatments were studied by quantitative reverse transcription PCR (qRT-PCR) and the function of the four genes in multidrug resistance were also validated by RNA interference (RNAi). Results showed that the expression of Bx-mrp1, Bx-mrp2, Bx-mrp3, and Bx-mrp4 were significantly increased when exposed to different nematicides, wherein, Bx-mrp4 exposed by 4.0 mg/mL of matrine own the highest expression level. The mortality rates of Bx-mrps silenced nematodes revealed significant increase(P < 0.05)under matrine, avermectin, and emamectin benzoate exposure. Specially, Bx-mrp4 exposed with 4.0 mg/mL matrine for 24 h own the highest mortality increase by 18.34%. After RNAi of Bx-mrps, feeding ability of the nematodes were also significantly decreased. These results demonstrate that Bx-mrps were linked to the detoxification process and feeding behavior of PWN. Silencing of Bx-mrps can lead to increased sensitivity of PWN to nematicides and decrease its feeding ability. Bx-mrps are potential new PWN control targets in the future.


Assuntos
Nematoides , Pinus , Tylenchida , Animais , Resistência a Múltiplos Medicamentos , Nematoides/genética , Doenças das Plantas , Tylenchida/genética , Xylophilus
19.
Sci Total Environ ; 794: 148514, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34218146

RESUMO

An increase in frequency, intensity and duration of drought events affects forested ecosystems. Trees react to these changes by adjusting stomatal conductance to maximize the trade-off between carbon gains and water losses. A better understanding of the consequences of these drought-induced physiological adjustments for tree growth could help inferring future productivity potentials of boreal forests. Here, we used samples from a forest inventory network in Canada where a decline in growth rates of black spruce (Picea mariana (Mill.) B.S.P.) and jack pine (Pinus banksiana Lamb.) occurred in 1988-1992, an exceptionally dry period, to verify if this growth decline resulted from physiological adjustments of trees to drought. We measured carbon and oxygen isotope ratios in growth rings of 95 spruces and 49 pines spanning 1985-1993. We used 13C discrimination (Δ13C) and 18O enrichment (Δ18O) as proxies for intrinsic water use efficiency and stomatal conductance, respectively. We studied how inter-annual variability in isotopic signals was linked to climate moisture index, vapor pressure deficit and annual snowfall amount. We found significantly lower Δ13C values over 1988-1990, and significantly higher Δ18O values in 1988-1989 and 1991 compared to the 1985-1993 averages. We also observed that a low climatic water balance and a high vapor pressure deficit were linked with low Δ13C and high Δ18O in the two study species, in parallel with low growth rates. The latter effect persisted into the year following drought for black spruce, but not for jack pine. These findings highlight that small differences in physiological parameters between species could translate into large differences in post-drought recovery. The stronger and longer lasting impact on black spruce compared to jack pine suggests a less efficient carbon use and a lower acclimation potential to future warmer and drier climate conditions.


Assuntos
Picea , Pinus , Canadá , Secas , Ecossistema , Árvores
20.
J Environ Manage ; 297: 113306, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34280864

RESUMO

Forest soil acidification caused by acid deposition is a serious threat to the forest ecosystem. To investigate the liming effects of biomass ash (BA) and alkaline slag (AS) on the acidic topsoil and subsoil, a three-year field experiment under artificial Masson pine was conducted at Langxi, Anhui province in Southern China. The surface application of BA and AS significantly increased the soil pH, and thus decreased exchangeable acidity and active Al in the topsoil. Soil exchangeable Ca2+ and Mg2+ in topsoil were significantly increased by the surface application of BA and AS, while an increase in soil exchangeable K+ was only observed in BA treatments. The soil acidity and active Al in subsoil were decreased by the surface application of AS. Compared with the control, soluble monomeric and exchangeable Al in the subsoil was decreased by 38.0% and 29.4% after 3 years of AS surface application. There was a minimal effect on soluble monomeric and exchangeable Al after the application of BA. The soil exchangeable Ca2+ and Mg2+ in the subsoil increased respectively by 54% and 141% after surface application of 10 t ha-1 AS. The decrease of soil active Al and increase of base cations in subsoil were mainly attributed to the high migration capacity of base cations in AS. In conclusion, the effect of surface application of AS was superior to BA in ameliorating soil acidity and alleviating soil Al toxicity in the subsoil of this Ultisol.


Assuntos
Pinus , Poluentes do Solo , Biomassa , Ecossistema , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
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