Tropical cyclones are large-scale strong wind disturbance events that occur frequently in tropical and subtropical coastal regions and often bring catastrophic physical destruction to ecosystems and economic disruption to societies along their paths. Major tropical cyclones can infrequently move into the midaltitudes and inland areas. Ecologically, tropical cyclones have profound impacts on diversity, structure, succession and function of forest ecosystems. The ecological effects are both dramatic and subtle. The dramatic effects can be visible, noticeable and to some extent predictable over the short-term and relatively well documented in the literature. However, the subtle effects are often invisible, complex and at smaller scale relatively unpredictable in the long-term. Many factors, meteorologic, topographic and biologic, simultaneously interact to influence the complexity of patterns of damage and dynamics of recovery. I present a global synthesis on the effects of tropical cyclones on forest ecosystems and the complexity of forest responses, with particular attention on the response to large hurricanes in the neotropics and the temperate North America, and strong typhoons on the subtropical and temperate forests in the East and Southeast Asia. Four major aspects provide on organizational framework for this synthesis: (1) consistent damage patterns, (2) factors that influence response patterns and predict damage risks, (3) complexity of forest responses and recovery, and (4) the long-term effects. This review reveals highly variable and complex effects of tropical cyclones on forest ecosystems. A deep understanding of the synergistic effects of tropical cyclones is essential for effective forest management and biodiversity conservation.
Plant roots play important roles in acquisition of water and nutrients, storage, anchoring, transport, and symbiosis with soil microorganisms, thus quantitative researches on root developmental processes are essential to understand root functions and root turnover in ecosystems, and at the same time such researches are the most difficult because roots are hidden underground. Therefore, how to investigate efficiently root functions and root dynamics is the core aspect in underground ecology. In this article, we reviewed some experimental methods used in root researches on root development and root system architecture, and summarized the advantages and shortages of these methods. Based on the analyses, we proposed three new ways to more understand root processes: (1) new experimental materials for root development; (2) a new observatory system comprised of multiple components, including many observatory windows installed in field, analysis software, and automatic data transport devices; (3) new techniques used to analyze quantitatively functional roots.
The Horqin Sandy Land (HSL), the largest sandy land in the semi-arid agro-pastoral ecotone of Northeast China, has been subject to desertification during the past century. In response, and to control the desertification, government implemented the Three-North Shelter/Protective Forest Program, world’s largest ecological reforestation/afforestation restoration program. The program began in 1978 and will continue for 75 years until 2050. Understanding the dynamics of desertification and its driving forces is a precondition for controlling desertification. However, there is little evidence to directly link causal effects with desertification process (i.e., on the changing area of sandy land) because desertification is a complex process, that can be affected by vegetation (including vegetation cover and extent of shelter forests) and water factors such as precipitation, surface soil moisture, and evapotranspiration. The objectives of this study were to identify how influencing factors, especially shelter forests, affected desertification in HSL over a recent decade. We used Landsat TM imagery analysis and path analysis to identify the effects of spatio-temporal changes in water and vegetation parameters during 2000–2010. Desertification was controlled during the study period, as indicated by a decrease in desert area at a rate of 163.3 km2 year−1 and an increase in the area with reduced intensity or extent of desertification. Total vegetation cover in HSL increased by 10.6 % during the study period and this factor exerted the greatest direct and indirect effects on slowing desertification. The contribution of total vegetation cover to controlling desertification increased with the intensity of desertification. On slightly and extremely severe desertified areas, vegetation cover contributed 5 and 42 % of the desertification reduction, respectively. There were significant correlations between total vegetation cover and water conditions (i.e., evapotranspiration and precipitation) and the area of shelter forests (P < 0.0001), in which water conditions and the existence of shelter forests contributed 49.7 and 12.8 % to total vegetation cover, respectively. The area of shelter forests increased sharply due to program efforts, but only shrub forests had significant direct effects on reducing the area of desertification categorized as slightly desertified. The reason for the lack of direct effect of increased arbor forests (accounting for 95.3 % of the total increase in shelter forests) on reducing desertification might be that the selected arbor species were not suited to water conditions (low precipitation, high evapotranspiration) prevailing at HSL. The establishment of shelter forests aided control of desertification in the HSL region, but the effect was less than expected. Effective control of desertification in the HSL region or other similar sandy areas will require greater improvements in vegetation cover. In particular, shrub species should be selected for plantation with reference to their potential to survive and reproduce in the harsh climatic and weather conditions typical of desertified areas.
To generate carbon credits under the Reducing Emissions from Deforestation and forest Degradation program (REDD+), accurate estimates of forest carbon stocks are needed. Carbon accounting efforts have focused on carbon stocks in aboveground biomass (AGB). Although wood specific gravity (WSG) is known to be an important variable in AGB estimates, there is currently a lack of data on WSG for Malagasy tree species. This study aimed to determine whether estimates of carbon stocks calculated from literature-based WSG values differed from those based on WSG values measured on wood core samples. Carbon stocks in forest biomass were assessed using two WSG data sets: (i) values measured from 303 wood core samples extracted in the study area, (ii) values derived from international databases. Results suggested that there is difference between the field and literature-based WSG at the 0.05 level. The latter data set was on average 16 % higher than the former. However, carbon stocks calculated from the two data sets did not differ significantly at the 0.05 level. Such findings could be attributed to the form of the allometric equation used which gives more weight to tree diameter and tree height than to WSG. The choice of dataset should depend on the level of accuracy (Tier II or III) desired by REDD+. As higher levels of accuracy are rewarded by higher prices, species-specific WSG data would be highly desirable.
Changes in land use cover, particularly from forest to agriculture, is a major contributing factor in increasing carbon dioxide (CO2) level in the atmosphere. Using satellite images of 1999 and 2011, land use and land use changes in the Kumrat valley KPK, Pakistan, were determined: a net decrease of 11.56 and 7.46 % occurred in forest and rangeland, while 100 % increase occurred in agriculture land (AL). Biomass in different land uses, forest land (FL), AL, and range land (RL) was determined by field inventory. From the biomass data, the amount of carbon was calculated, considering 50 % of the biomass as carbon. Soil carbon was also determined to a depth of 0–15 and 16–30 cm. The average carbon stocks (C stocks) in all land uses ranged from 28.62 ± 13.8 t ha−1 in AL to 486.6 ± 32.4 t ha−1 in pure Cedrus deodara forest. The results of the study confirmed that forest soil and vegetation stored the maximum amount of carbon followed by RL. Conversion of FL and RL to AL not only leads to total loss of about 56 % (from FL conversion) and 37 % (RL conversion) of soil carbon in the last decades but also the loss of a valuable carbon sink. In order to meet the emissions reduction obligations of the Kyoto Protocol, Conservation of forest and RL in the mountainous regions of the Hindu Kush will help Pakistan to meet its emissions reduction goals under the Kyoto Protocol.
We assessed the potential of white poplar (Populus alba L.) and its inter-sectional hybridization with euphrates poplar (P. euphratica Oliv.) for carbon storage and sequestration in central Iran. Trials were established at planting density of 2,500 trees per hectare in block randomized design with three replicates. After 6 years, we measured the above-ground biomass of tree components (trunk, branch, bark, twig and leaf), and assessed soil carbon at three depths. P. alba × euphratica plantation stored significantly more carbon (22.3 t ha−1) than P. alba (16.7 t ha−1) and P. euphratica × alba (13.1 t ha−1). Most of the carbon was accumulated in the above-ground biomass (61.1 % in P. alba, 72.4 % in P. alba × euphratica and 56.0 % in P. euphratica × alba). There was no significant difference in soil carbon storage. Also, biomass allocation was different between white poplar P. alba and its inter-sectional hybridization. Therefore, there was a yield difference due to genomic imprinting, which increased the possibility that paternally and maternally inherited wood production alleles would be differentially expressed in the new crossing.
We evaluated the biomass and ergosterol content of Hericium erinaceus mycelium, and extracellular enzyme activities in H. erinaceus liquid culture following salicylic acid (SA) and methyl jasmonic acid (MeJA) supplementation. The optimal SA concentration was 100 µmol·L−1, where the highest ergosterol content of 2.33 mg·g−1 was obtained following 6-day cultivation with 100 µmol·L−1 SA supplementation, and which was significantly higher than the unsupplemented control (p < 0.01). Following 4-day supplementation with 50 μmol·L−1 MeJA, the highest ergosterol content obtained was 1.988 mg·g−1, which was 25.8 % higher than the unsupplemented control. Our data indicate that SA and MeJA supplementation improves ergosterol content in H. erinaceus mycelium.
The amounts of litter produced and nutrients returned play a fundamental role in the productivity and biogeochemical and nutrient cycling of forest ecosystems. We monitored annual litterfall production, nutrient return, and monthly dynamics over a one-year period in Chinese fir plantations aged 10, 22, and 34 years. Our objective was to quantify litterfall and nutrient return over a complete harvest rotation of Chinese fir. Annual litterfall production increased with stand age and was recorded as (3,294.6 ± 360.4), (3,733.9 ± 211.2), and (4,876.1 ± 212.8) kg ha−1 a−1 in stands aged 10, 22 and 34 years, respectively. Total litter production was significantly greater in the stand aged 34 years than in the stand aged 10 years (p < 0.05). With the exception of miscellaneous components, needle litterfall constituted the highest proportion (27.5–43.6 %), followed by branches/twigs (9.5–16.6 %). In all three plantations, annual total nutrient return to soil was in the order of C (1,119.95–2,709.05 kg ha−1 a−1) > N (39.32–62.04 kg ha−1 a−1) > K (15.95–22.44 kg ha−1 a−1) > P (1.30–1.63 kg ha−1 a−1). C, N, K and P input to soil was significantly lower in the 10-year-old stand in comparison to the 22- and 34-year-old stands (p < 0.05). Litterfall production and nutrient return (C, N and K) followed similar patterns, and C and N input to soil was significantly related to litterfall production (needle, branch and total litterfall). C, N, P and K input to soil and total litterfall production were mainly driven by needle litterfall.
As more and more farmland is converted to forestry, the need for effective decision support regarding the use of land in the fragile ecological environment of the Loess Plateau hilly-gully area. The Luoyugou watershed was chosen as the study area to calculate the single dynamic degree, integrated dynamic degree, and change indexes of land use, as well as the land-use type transition matrix. This was done by interpreting the TM and SPOT images of the Luoyugou watershed in 1986, 1995, and 2004 and making statistical analysis. The results of our statistical analysis show that the conversion of slope farm land to terrace and forest land plays a dominant role in land-use changes in the Luoyugou watershed from 1986 to 2004. The land-use changes are mainly driven by population growth, socio-economic development, consumer spending, and investment in forest ecology.
Chinese fir (Cunninghamia lanceolata (Lamb.) Hook) is one of the most important coniferous tree species used for timber production in China. Here, we conducted a sequence-related amplified polymorphism (SRAP) primer screening assay with a total of 594 primer combinations, using 22 forward and 27 reverse primers on four representative Chinese fir genotypes. The obtained results indicated that Chinese fir genomic DNA has a notable amplification bias on the employed forward or reverse primer nucleotides (3′ selection bases). Out of the tested primer sets, 35 primer combinations with clearly distinguished bands, stable amplification, and rich polymorphism were selected and identified as optimal primer sets. These optimal primer pairs gave a total of 379 scorable bands, including 265 polymorphic bands, with an average of 10.8 bands and 7.6 polymorphic bands per primer combination. The produced band number for each optimal primer set ranged from 7 to 14 with a percentage of polymorphic bands spanning from 33.3 to 100.0 %. These primer combinations could facilitate the next SRAP analysis assays in Chinese fir.
Lepidium sativum (commonly known as garden cress) belongs to the family Brassicaceae. It is a fast-growing erect, annual herbaceous plant. Its seeds possess significant fracture healing, anti-asthmatic, anti-diabetic, hypoglycemic, nephrocurative and nephroprotective activities. In the present study, we assessed the genetic diversity of various genotypes of L. sativum using inter-simple sequence repeat (ISSR) markers. Out of 41 ISSR primers screened, 32 primers showed significant, clear and reproducible bands. A total of 510 amplified bands were obtained using 32 ISSR primers, out of which 422 bands were polymorphic and 88 bands were monomorphic. The percentage of polymorphism was found to be 82. A total of 35 unique alleles ranging insize from 200 to 2,900 bp were observed. Cluster analysis based on unweighted pair-group method, arithmetic mean divided the 18 genotypes into two main clusters, with the first having only HCS-08 genotype of L. sativum and other having all of the other 17 genotypes. The Jaccard similarity coefficient revealed a broad range 32–72 % genetic relatedness among the 18 genotypes.
We assessed chemical composition and variation in oil content and seed weight of 40 wild-growing almonds (Prunus L. spp.) accessions collected from different parts of Iran. There were significant differences in kernel weight and oil parameters. Accessions ranged from 0.20 to 1.5 g in kernel weight, 0.2–3.0 mm in shell thickness, and 16–55 % in oil content. The predominant vegetable oil components of kernels were 4.6–9.5 % palmitic acid, 0.4–0.8 % palmitoleic acid, 1.0–3.4 % stearic acid, 48.8–88.4 % oleic acid and 11.3–33.2 % linoleic acid. Linolenic acid was detected in 15 accessions. High heritability was recorded for all studied traits and was maximum for shell thickness (98.5 %) and minimum for oil content (97.1 %). Maximum and minimum ‘Euclidean’ pair wise dissimilarities were 17.9 and 0.5, respectively. All 40 accessions were grouped into two major clusters.
We studied relationships between stand structure and stand stability according to thinning intensity in an afforested oriental beech stand. Various thinning intensities were applied in sample stands. We sampled eight plots in stands that were lightly thinned, eight plots in heavily thinned stands and eight plots in unthinned stands as a control. Height and diameter distributions of the stands were measured to assess stand structure. We quantified individual tree stability and collective stability. Heavy thinning during the first thinning operation damaged the storied structure of the stand in thicket stage and affected collective structuring ability. While most control plots had multi-storied stands, after light and heavy thinning two-storied structure became more common. Large gaps occurred in the canopy after heavy thinning. On average, nine tree collectives were formed per sampling plot in the untreated stand, seven collectives after thinning in 2008 and four collectives after thinning in 2009. Stable trees accounted for 17 % of trees in control plots, 24 % in lightly thinned plots, and 15 % in heavily thinned plots. Collective stability values were 83 % in control plots, 82 % in lightly thinned plots and 36 % in heavily thinned plots. We conclude that it is necessary to retain collective structuring capacity during thinning operations for sustaining stand stability.
This paper presents preliminary assessment of seedling survival and growth of green alder (Alnus viridis (Chaix) DC. in Lam. & DC.) planted on fly ash disposal sites. This kind of post-industrial site is extremely hard to biologically stabilize without top-soiling. The experiment started with surface preparation using NPK start-up mineral fertilizer at 60–36–36 kg ha−1 followed by initial stabilization through hydro-seeding with biosolids (sewage sludge 4 Mg ha−1 dry mass) and a mixture of grasses (Dactylis glomerata L. and Lolium multiflorum Lam.) (200 kg ha−1). Subsequently, three-years-old green alder seedlings were planted in plots on two substrate variants: the control (directly on combustion waste) and plots with 3 dm3 lignite culm from a nearby mine introduced into the planting pit. Five years of preliminary monitoring show good survival seedling rates and growth parameters (height (h), average increase in height (Δh), number of shoots (Lo) and leaf nitrogen supply in the fly ash disposal habitat. Treatment of the site with a combination of lignite culm in planting pits and preliminary surface preparation by hydro-seeding and mineral fertilization had the most positive effect on green alder seedling parameters. The results indicate that it is possible and beneficial to use green alder for biological stabilization on fly ash disposal sites.
Progeny studies of Jatropha curcas and Pongamia pinnata were carried with respect to bioproductivity, pod and seed characters which is one of the selection methods in tree improvement programmes. Variations in bioproductivity and biodiesel parameters of both the plants were compared every 6 months for 4 years of investigation and analyzed by analysis of variance and correlation coefficient by Pearson’s method using software Graphpad instat 3.06 (for Windows and Mac). P. pinnata has better germination rate (71.4 %), 100 pod weight (PW) (311.59 g) and 100 seed weight (SW) (173.46 g) as compared to J. curcas for germination rate (43.2 %), 100 PW (111.29 g) and 100 SW (67.46 g). P. pinnata has strong correlation for plant height to canopy growth (CG) (0.948), collar diameter (CD) (0.994), number of branches per plant (NBP) (0.995) and to number of leaves per branch (NLB) (0.862) as compared to J. curcas which showed good correlation among plant height to CG (0.976), CD (0.970), NBP (0.988), NLB (0.920) and to number of pods per branch (0.657). However, J. curcas depicted negative correlation for pod breadth to seed length (SL) (−0.447), seed breadth (−0.248) and to seed thickness (ST) (−0.364) and among the 100 PW to SL (−0.199), ST (−0.220) and to 100 SW (−0.704). About 4 kg of P. pinnata seeds were required for each liter of crude oil which yields 896 ml of biodiesel on transesterification as compared to 5.66 kg of J. curcas seeds for a liter of crude oil, producing about 663 ml of biodiesel. The quality of biodiesel meets the major specification of American Society for Testing and Materials (ASTM) standards for biodiesel. The crude glycerin and seed cake obtained as byproduct during biodiesel production were also measured which can be purified and used in composting, animal feeds, pharmaceuticals and cosmetic industries.
In addition to pests and diseases, weeds are a major problem in poplar nursery production. The possibilities of herbicide application in juvenile poplar growth were researched, taking into account that weeds are one of the main limiting factors. The following pre-emergence herbicides were tested: acetochlor, S-metolachlor, metribuzin, oxifluorfen, and dimethenamid during two vegetation seasons at two locations, which differed by the soil physico-chemical characteristics. The study results show that the number of weeds on sample plots was significantly reduced by the tested herbicides when compared to control plots. The highest reduction in the number of weeds was achieved using the herbicides acetochlor and metribuzin. However, metribuzin showed a phytotoxic effect on sandy soil. Metribuzin application is recommended only on the soils with higher contents of organic matter, where the phytotoxic effect was absent. Acetochlor, S-metolachlor, oxifluorfen, and dimethenamid were not phytotoxic to poplars and can be used for weed suppression in the production of poplar plants.
Species of Paulownia are fast-growing trees that are planted in many countries in green spaces and agroforestry systems. We studied the influence of irrigation on the diameter growth of 2-year-old Paulownia tomentosa saplings planted in 3 m × 3 m grids at Nazlou Campus of Urmia University, Iran. Completely randomized experimental design was used with four irrigation amount, viz. 10, 15, 20 and 25 L, and three irrigation intervals, viz. 3- and 6-days, in 8 replications. During the growth season, we measured collar diameters of all saplings at the end of each month. Diameter growth declined with reduced irrigation amount and increased irrigation interval. The lowest average diameter growth (9 mm) was recorded for 10 L water at 6-day intervals and maximum average diameter growth (28.7 mm) was recorded for 25 L volume at 3-day intervals. The latter treatment resulted in significantly greater diameter growth than any other treatment (except 20 L at 3-day intervals). More than 80 % of diameter growth was achieved in the first 3 months. Therefore, it is essential to irrigate with 25 L of water at 3-day intervals during the first three growth months to achieve maximum diameter growth for 2-year-old P. tomentosa saplings.
Juri is a biodiversity-rich primary forest in Bangladesh, which remains ecologically unexplored. We identified tree species and examined the richness, alpha (α) diversity and floristic similarity patterns within the identified communities. Vegetation and environmental data were sampled in 120 (0.04 ha) study plots. Tree communities were delimited by two-way indicator species analysis (TWINSPAN). In total, 78 tree species of 35 families and 58 genera were identified. TWINSPAN identified six tree communities: A—Tricalysia singularis; B—Kydia calycina-Castanopsis tribuloides; C—Polyalthia simiarum-Duabanga grandiflora; D—Ficus roxburghii; E—Artocarpus lacucha; F—Artocarpus lacucha. Mean richness, Shannon and Gini-Simpson indices were highest for the Polyalthia simiarum-Duabanga grandiflora community, while Ficus roxburghii showed lowest diversity. Significant differences (p = 0.05) in three diversity indices were recorded between Polyalthia simiarum-Duabanga grandiflora and Ficus roxburghii. Tree compositional similarity was greatest between Kydia calycina-Castanopsis tribuloides and Polyalthia simiarum-Duabanga grandiflora (0.712).
Functional diversity is significant to ecological processes of plant communities. We analyzed the variation of functional diversity of endangered species, Cercidiphyllum japonicum, communities along an elevational gradient in the Shennongjia Reserve, central China. Sixty plots of 10 × 20 m from 1,350 to 2,050 m were set up and species composition, traits and environmental variables were measured and recorded. These data were analyzed using five functional diversity indices, functional attribute diversity, modified functional attribute diversity, plot based functional diversity, community based functional diversity and Rao’s functional diversity indices (Rao’s index), Functional diversities of C. japonicum communities were rich and varied greatly. Functional diversity declined non-linearly with increasing elevation. Functional diversity was significantly correlated with species richness and heterogeneity. Elevation was a key environmental variable influencing functional diversity and species diversity. The five functional diversity indices were all effective for measuring functional diversity of communities. Functional diversity can be used as an indicator of conservation efficiency of endangered species such as C. japonicum.
Thamnocalamus falconeri, Hook.f. ex Munro., an important bamboo species belonging to the family Poaceae, locally known as Ringal, occurs in the hills of Uttarakhand, India. This species has been traditionally exploited by local communities to support their livelihoods. Increasing needs of the hill villages impose unsustainable pressure on natural stands of Ringal in the Uttarakhand hills and forests have been degraded. The long history of excessive cutting of Ringal from natural forests and the lack of replanting threaten villager livelihoods. Replanting is required to conserve the species. We propose a protocol for generation of planting material through axillary bud proliferation for multiplication and conservation of this species. We collected offsets/rhizomes from a natural stand of T. falconeri in the Chopta Mandal areas (Chamoli district, India). These were planted at sites of varied elevation and fresh single nodal segments were collected from them as explants. Different sterilization treatments were assessed to combat contamination. Among these, treatment of 0.1 % HgCl2 followed by 5 % NaOCl, proved best. Among two cytokinin treatments, viz. BAP and Kinetin, singly or in combination, BAP alone (5 mg L−1) proved superior and resulted in 100 % bud break. BAP-supplemented MS media yielded maximum vigorous shoot formation (90 %) and maximum number of shoots (8.9). Subculturing of shoots on the same medium with similar BAP treatment (5 mg L−1 BAP) enabled continuous production of healthy shoots at similar frequency. Maximum rooting (100 %) was recorded on half-strength MS medium supplemented with 5 mg L−1 IBA. Micropropagated plants were hardened and acclimatized in soil mixture (2:1:1) and then transplanted to field sites (Magra, Uttarakhand, 1,834 m). Eight to ten months after field transplantation we recorded 100 % survival of transplanted material. This micropropagation protocol could be used successfully for raising a stock of genetically homogenous plant material in bulk for field plantations and for conservation of the species.
We investigated the floristic composition of the Hyrcanian forests and the related forest-steppe ecotone in Northern Iran by using two long ecological transects, from lowland to upper mountain areas. The study was conducted during 2008 and 2009 and yielded the identification of 395 plant taxa belonging to 233 genera and 78 families. Dicots with 300 taxa were the richest groups of the flora, followed by monocots with 75 taxa, pteridophytes with 18 species, and gymnosperms with two species. The largest families were Asteraceae (33 taxa); Rosaceae (32 taxa); and Poaceae (30 taxa), and the most diverse genera included Carex (15 taxa); Alchemilla (7 taxa); and Poa, Geranium and Acer (6 taxa each). Hemicryptophytes were the most dominant life forms in the area (40 %); followed by geophytes (31.4 %); phanerophytes (15.4 %); therophytes (11.4 %); and chamaephytes (1.8 %). Phytogeographically, Euro-Siberian/Irano-Turanian elements (86 taxa, 21.8 %) and Euro-Siberian elements (85 taxa, 21.5 %) were the most common chorotypes in the area. Out of 395 taxa, 66 taxa (16.7 %) were endemics and subendemics in Iran, of which 26 taxa were exclusively endemics of Iran. According to the IUCN Red List Categories, 48 threatened plant taxa were found in the study area. Plant diversity, life form, and chorotypes in the current study were compared with similar transect studies in other areas of the Hyrcanian forests and in different altitudinal belts, using Sørenson similarity indices. Floristic composition of the surveyed transects demonstrated almost 50 % similarity between them.
Phellodendron amurense has been used for many years as a medical plant in traditional Chinese medicine and has shown great prospect in recent clinical trials for future applications. Berberine is an essential active compound contained in P. amurense. Our objective in this study was to quantify the content of berberine in P. amurense from sites at different elevations on Changbai Mountain. We collected samples of P. amurense from five different elevations on Changbai Mountain. Berberine in samples was extracted by ultrahigh pressure extraction (UPE). And the quantity was measured by high performance liquid chromatography (HPLC). First, the optimal HPLC conditions for berberine were identified with satisfactory precision (relative standard deviation, R SD < 5.6 %), good accuracy (relative error, R E < 3.6 %) and good linear relation (R 2 = 0.9998) in the range of 6.576–328.8 mg·L−1. Second, the combination of UPE and HPLC methods in quantitative analysis of berberine showed high repeatability (R SD = 3.28 %), reproducibility (R SD = 4.72 %), stability (R SD < 1.27 %) and good recovery (99.54 %) for real plant materials. Samples from Heilongjiang Province at the lowest elevation contained the highest amount of berberine. Similarly, the lowest amount of berberine was recorded in samples from Changbai Forest Bureau of Jilin Province collected at the highest elevation in this paper. The proposed UPE–HPLC method is simple, reliable and low-cost for quantitative analysis of berberine. Content of berberine in P. amurense varied significantly by site on Changbai Mountain.
We quantified morphological and hydrographical characteristics of two drainage basins (Chanioti and N. Skioni) on Cassandra peninsula of Chalkidiki (North Greece), and evaluated the effectiveness of post-fire flood and erosion control works. The drainage basins were chosen because of their severe damage by fire, post-fire potential for erosion and flood due to the steep relief, and the importance of the area for residential and tourism development. The first measures taken in the area after the fire were salvage cutting of burned trees, a total ban on grazing, and construction of three types of works, log erosion barriers (LEBs), log check dams and contour branch barriers. Almost all necessary post-fire works were completed in both catchments but many construction failures were recorded. Approximately 75 % of the LEBs and 45 % of the contour branch barriers functioned properly, while the remainder failed. Nearly 80 % of the log dams were sedimented to 0–20 % of the dam height, 14.3 % were 20–40 % filled and 5.9 % collapsed. Despite these failures, peak discharge declined by 10.5 % in Chanioti and 20.4 % in N. Skioni catchment. The main reasons for works failures were the rush of construction and the limited supervision of workers, which resulted in floods during the years that followed.
Both fecundities and egg hatchabilities were compared among three populations of Dastarcus helophoroides Fairmaire adults (Coleoptera: Bothrideridae) fed on three types of artificial diets (Diet of formula 1 composed of silkworm pupa powder, dried yeast powder, sucrose, peptone, egg yolk powder and poplar branch powder. Diet of formula 2 composed of silkworm pupa powder, dried yeast powder, sucrose, egg yolk powder, poplar branch powder, cricket powder, benzoic acid and distilled water. Diet of formula 3 composed of pine bark powder and Monochamus alternatus larva powder). for 90 days. The three diets showed no significant difference regarding the average number of eggs deposited by all D. helophoroides females (16622.3–23874.7); the average number of eggs per female (1278.6–1836.5); and the average number of eggs per female per day (14.2–20.4). The number of eggs one cluster contained mainly (82.06–82.66 %) lied in 1–100 eggs, and the average number of eggs per cluster ranged from 61.7 to 63.1. In the first 10-day period, the number of eggs deposited by all females fed on formula 1 was significantly larger than that on formula 3. The eggs deposited in the last four 10-day periods were more than in the former five 10-day periods, on formula 3. There were no significant differences in hatchability of total eggs among the three artificial diets, and the average corrected egg hatchability ranged from 82.85 to 84.78 %. No significant differences in the adult mortality and mean weight gain of D. helophoroides were found after feeding on three artificial diets. Our results suggest that D. helophoroides adults were not specialized on the diet, and the diet types might have little effect on fecundity and egg hatchability in D. helophoroides, as long as sufficient nutrition was supplied.
The uredinial stage in the life cycle of Melampsora larici-populina on poplar leaves is the most important pathogenic phase. We captured partial phases of uredinial infection in the wild, aiming to reconstruct the process of uredinial ontogeny by using scanning and transmission electron microscope. At the initial infection stage, germ tubes germinated from the echinulate urediniospores. Germ tubes were frequently seen to merge with the leaf surface and cuticle breakage was observed, indicating direct hyphal penetration. Stomata penetration occurred commonly, sometimes with more than one germ tube penetrating the same stoma. Melampsora larici-populina did not form appressoria in the infection process, implying that infectious behavior of this pathogen may differ from the other rust pathogens. In general, germ tubes branched randomly, and no distinct evidence indicated that stoma could induce or orient germ tube branches. However, oriented germ tube growth has been occasionally observed in other studies. The urediniospores collapsed and finally wizened when they became nutrient stressed. At the last stage of infection, the uredinia erupted from the leaf epidermis and appeared as orange pustules on the leaf surface.
The pinewood nematode (PWN), Bursaphelenchus xylophilus, has become one of the most severe threats to pine forest worldwide. Nematodes, migrating through resin canals and feeding on the living cells, induce rapid metabolic changes in ray parenchyma cells, create cavitation areas, decrease xylem water content and oleoresin exudation, and cause necrosis of parenchyma and cambial cells. This study focused on the impact of PWN infection on technological parameters of wood and evaluated the impact of anatomic and biochemical incidences of tree defense reactions on basic density, extractive content and moisture sorption properties of Pinus pinaster wood. Samples of infected and uninfected wood were studied. The presence of nematodes reduced wood basic density by 2 % and decreased the total content of extractives in infected wood as compared with uninfected (5.98 and 8.90 % of dry wood mass, respectively). Extractives in infected trees had inverse distribution along the trunk as compared with uninfected trees. The adsorption isotherms for infected and uninfected wood had similar positioning. We recorded differences (some statistically significant) in the equilibrium moisture content of infected and uninfected wood under varying environmental conditions. Despite the verified differences in wood basic density, extractive content and moisture sorption properties, the overall conclusion is that the PWN had a slight impact on these characteristics of wood.
We studied the effect of growth on wood anatomical dimensions and specific gravity of seed-raised plantation wood of Dalbergia sissoo with twelve trees of different diameters and similar ages. Fiber length ranged from 925 to 1,287 μm, fiber-diameter was 19–23 μm, wall thickness was 4.2–5.4 μm, vessel-element-length was 152–188 μm, vessel-element-diameter was 152–200 μm, and specific gravity was 0.59–0.72. Growth parameters including tree height, diameter at breast height, net primary productivity and net ecosystem productivity were significantly and positively correlated. Growth parameters showed non-significant positive relationships with fiber-length, fiber diameter, wall thickness, vessel element length, and vessel element diameter. The trend of wood traits increased with growth. Specific gravity showed non-significant negative relationships with growth parameters. Although the growth rate had varied relationships with wood properties, as reported by various workers, the wood element dimensions showed no significant relationship with growth parameters and there was little effect of growth rate on wood traits in seed-raised plantation of D. sissoo.
The objective of this investigation was to introduce a cement-based composite of higher quality. For this purpose new hybrid nanocomposite from bagasse fiber, glass fiber and multi-wall carbon nanotubes (MWCNTs) were manufactured. The physical and mechanical properties of the manufactured composites were measured according to standard methods. The properties of the manufactured hybrid nanocomposites were dramatically better than traditional composites. Also all the reinforced composites with carbon nanotube, glass fiber or bagasse fiber exhibited better properties rather than neat cement. The results indicated that bagasse fiber proved suitable for substitution of glass fiber as a reinforcing agent in the cement composites. The hybrid nanocomposite containing 10 % glass fiber, 10 % bagasse fiber and 1.5 % MWCNTs was selected as the best compound.
We prepared spherical microcapsules modified by carboxymethyl cellulose (CMC) with urea-formaldehyde (UF) resin as a shell material with a two-step process by in situ polymerization, and characterized the microcosmic features, chemical structure, and thermal performance of the microcapsules by SEM, FTIR, DSC, and TGA. We studied the effects of different experimental parameters of curing pH, the amounts of the emulsifier and emulsion speed. The CMC-UF microcapsules had good heat resistance and stability. The enthalpy of CMC-UF microcapsules reached 50.33 J g−1. Therefore, CMC-UF resin can be used as a potential wall material of phase change materials.
Bamboo residues were liquefied in a mixture of glycerol and methanol in the presence of sulfuric acid using microwave energy. We investigated the effects of liquefaction conditions, including glycerol/methanol ratio, liquefaction temperature, and reaction time on the conversion yield. The optimal liquefaction conditions were under the temperature of 120 °C, the reaction time of 7 min, the glycerol–methanol–bamboo ratio of 8/0/2 (W/W), and the microwave power of 300 W. Maximum conversion yield was 96.7 %. The liquid products were separated into two contents (water soluble part and precipitate part) by addition of a sufficient amount of water. By Fourier transform infrared (FT-IR), the water soluble content mainly contained glycerol and its derivate and carbohydrate degradation products, and the precipitate content was mainly lignin derivatives.