scholarly journals Effect of Leaf Litter from Cistus ladanifer L. on the Germination and Growth of Accompanying Shrubland Species

Plants ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 593
Author(s):  
Juan Carlos Alías Gallego ◽  
Jonás González Caro ◽  
Virginia Hinojal Campos ◽  
Natividad Chaves Lobón
Keyword(s):  
Leaf Litter ◽  
Woody Species ◽  
Negative Influence ◽  
Cistus Ladanifer ◽  
Retama Sphaerocarpa ◽  
Allelopathic Activity ◽  
Lavandula Stoechas ◽  
Negative Effect ◽  
Composition Structure ◽  
Germination And Growth

Most communities with the presence of Cistus ladanifer are characterised by the low richness of accompanying species, with C. ladanifer, in most cases, exceeding 70% of the coverage of woody species. This fact could be due to the allelopathic activity attributed to compounds present in the leaves of C. ladanifer, which may have a negative effect on the germination and growth of woody species that share its habitat. One of the possible ways of incorporating allelopathic compounds to the soil is the degradation of leaf litter. Therefore, the aim of this study was to determine how the presence of leaf litter from C. ladanifer affects accompanying species. Under controlled conditions, we analysed the effect of C. ladanifer leaf litter on the germination and growth of seedlings of five species that share their habitat with C. ladanifer (Retama sphaerocarpa, Cytisus multiflorus, Lavandula stoechas, Cistus salviifolius, and Cistus crispus). Additionally, the effect of leaf litter on the species itself, C. ladanifer, has been studied. The experiments were designed with different concentrations of leaf litter (UL) and leaf litter from which the compounds with allelopathic activity were extracted (WL). The results show that such effect greatly depends on the analysed species, with L. stoechas being the most negatively affected species. On the other hand, C. multiflorus and C. salviifolius were only negatively affected at the stage of seedling growth. The results reveal the involvement of leaf litter in the allelopathic activity attributed to C. ladanifer and that its presence has a negative influence on the germination and growth of accompanying woody species. This shows the need to delve into the potential relevance of allelopathy as an interaction that determines the composition, structure and dynamics of a community.

scholarly journals Evaluation of foam properties of saponin from Ilex paraguariensis A. St. Hil. (Aquifoliaceae) fruits

2010 ◽  
Vol 46 (2) ◽  
pp. 237-243 ◽  
Author(s):  
Gizele Scotti do Canto ◽  
Janine Treter ◽  
Samanta Yang ◽  
Gustavo Luís Borré ◽  
Maria Paula Garofo Peixoto ◽  
...  
Keyword(s):  
Sodium Dodecyl ◽  
Negative Influence ◽  
Molecular Surface ◽  
Ilex Paraguariensis ◽  
Film Drainage ◽  
Drainage Rate ◽  
Negative Effect ◽  
Foam Properties ◽  
Saponin Fraction ◽  
Film Thinning

Saponins are natural compounds able to form abundant foam, a desirable quality required in some chemical, foods, cosmetic and pharmaceutical processes. Ilex paraguariensis A. St. Hil. (Aquifoliaceae) known as mate, is a South American widely cultivated specie due to the preparation of a tea-like beverage from its leaves. Moreover, its green fruits are a rich source of non-toxic and very low haemolytic saponins. In this study, mate saponin fraction (MSF) was evaluated as a foam former, focusing on its foamability, foam lifetime, and film drainage in the presence of different electrolytes (ionic strength I = 0.024 M). Sodium dodecyl sulphate (SDS) and polysorbate 80 (Poly-80) were used as reference surfactants. The critical micelle concentration (CMC), the minimum attainable surface tension (γCMC), surface excess concentration (Γ) and cross-section molecular surface (A) values of MSF were comparable to those of Poly-80. The foamability of MSF and both reference surfactants was equivalent. The addition of MgCl2 resulted in a negative effect on MSF foamability. The salts NaCl, KBr, and KNO3 exhibited a negative influence on MSF foam lifetime. Similar behavior was observed for MSF film drainage (order of activity: Na2HPO4 > MgCl2 ≈ NaCl ≈ KNO3 > KBr), where a primary fast film drainage rate was followed by film thinning stabilization after around 5 min. The behavior described above seems to be uncorrelated to the solutions' zeta potential.

scholarly journals Tree-Ring Growth of Larch (Larix decidua Mill.) in the Polish Sudetes—The Influence of Altitude and Site-Related Factors on the Climate–Growth Relationship

Forests ◽  
2018 ◽  
Vol 9 (11) ◽  
pp. 663 ◽  
Author(s):  
Małgorzata Danek ◽  
Monika Chuchro ◽  
Adam Walanus
Keyword(s):  
Tree Ring ◽  
Climatic Factors ◽  
Negative Relationship ◽  
Thermal Conditions ◽  
Cambial Activity ◽  
Negative Influence ◽  
Larix Decidua ◽  
Related Factors ◽  
Local Conditions ◽  
Negative Effect

In this paper, the first study of a regional character on the influence of climatic factors on the tree-ring growth of European larch (Larix decidua Mill.) growing in the Polish Sudetes is presented. The obtained results indicate the relatively high diversity of the climatic signal observed in the tree rings of larches growing in the Sudetes. The most significant differentiating factor is altitude. The results suggest that the possible influence of local conditions (e.g., summit proximity, soil and bedrock characteristics, and exposure to strong winds) could also be of importance. A positive relationship between tree-ring growth and May temperatures was noted throughout the area; this indicates the principal importance of thermal conditions during the initial stage of cambial activity and tree-ring formation in larches from the Sudetes. The negative effect of the temperatures in the previous summer upon the tree-ring growth of larch in the subsequent year was also observed. The studies also indicate the negative influence of the water stress in summer (particularly in July of the previous year) upon the growth of trees. The negative relationship between tree-ring growth and the previous November temperature could be explained by the need for a late-autumn cooling, which affects the development of assimilation apparatus in spring of the subsequent year, which indirectly affects the tree-ring growth in the same year.

scholarly journals A Spatial-Temporal Adaptive Neighborhood-Based Ratio Approach for Change Detection in SAR Images

2018 ◽  
Vol 10 (8) ◽  
pp. 1295 ◽  
Author(s):  
Huifu Zhuang ◽  
Hongdong Fan ◽  
Kazhong Deng ◽  
Guobiao Yao
Keyword(s):  
Change Detection ◽  
Window Size ◽  
Speckle Noise ◽  
Adaptive Strategy ◽  
Negative Influence ◽  
Sar Images ◽  
Spatial Homogeneity ◽  
Difference Image ◽  
Negative Effect ◽  
Adaptive Neighborhood

The neighborhood-based method was proposed and widely used in the change detection of synthetic aperture radar (SAR) images because the neighborhood information of SAR images is effective to reduce the negative effect of speckle noise. Nevertheless, for the neighborhood-based method, it is unreasonable to use a fixed window size for the entire image because the optimal window size of different pixels in an image is different. Hence, if you let the neighborhood-based method use a large window to significantly suppress noise, it cannot preserve the detail information such as the edge of a changed area. To overcome this drawback, we propose a spatial-temporal adaptive neighborhood-based ratio (STANR) approach for change detection in SAR images. STANR employs heterogeneity to adaptively select the spatial homogeneity neighborhood and uses the temporal adaptive strategy to determine multi-temporal neighborhood windows. Experimental results on two data sets show that STANR can both suppress the negative influence of noise and preserve edge details, and can obtain a better difference image than other state-of-the-art methods.

scholarly journals PENGARUH SPREAD, MARKET VALUE, VARIANCE RETURN DAN DIVIDEND PAYOUT RATIO TERHADAP HOLDING PERIOD SAHAM

2016 ◽  
pp. 168
Author(s):  
Ni Luh Ayu Yulita Utami ◽  
Ida Bagus Panji Sedana
Keyword(s):  
Stock Exchange ◽  
Participant Observation ◽  
Secondary Data ◽  
Market Value ◽  
Negative Influence ◽  
Dividend Payout ◽  
Holding Period ◽  
Significant Negative Effect ◽  
Return Variance ◽  
Negative Effect

The purpose of this study was to determine the effect spreads, market value, variance return and dividend payout ratio of the holding period of the stock chemical and basic industry sectors 2011-2014 period. The study was conducted using the method of non-participant observation, the data used is secondary data obtained in the Indonesia Stock Exchange (IDX) through the site www.idx.co.id. The sample used in the study of eight companies which were determined using purposive sampling method. The analysis technique used in this research is multiple linear regression. Based on the analysis, variable spreads had a negative influence is not significant, the market value has a significant negative effect, return variance has no significant negative effect and the dividend payout ratio has a significant positive pengeruh. Simultaneously independent variables significantly influence the holding period. Based on the results of this study should investors pay attention to the variable market value and the dividend payout ratio that has a significant influence on the holding period

scholarly journals Composition of essential oil and allelopathic activity of aromatic water of Aster lanceolatus Willd: (Asteraceae)

2009 ◽  
Vol 45 (3) ◽  
pp. 469-474 ◽  
Author(s):  
Josiane de Fátima Gaspari Dias ◽  
Obdúlio Gomes Miguel ◽  
Marilis Dallarmi Miguel
Keyword(s):  
Essential Oil ◽  
Lactuca Sativa ◽  
Extraction Process ◽  
Caryophyllene Oxide ◽  
Allelopathic Activity ◽  
Germination And Growth

The essential oil obtained from flowers of Aster lanceolatus was submitted the CG-MS and presented as result thirteen substances with largest concentration; among them, the caryophyllene oxide with the larger one. The aromatic water obtained during the extraction process of this essential oil was forwarded to allelopathic test, and demonstrated to be capable to inhibit the germination and growth of Lactuca sativa.

scholarly journals Influence of the constituents of Izatison, DMSO and PEG400, on the growth and the grain productivity of the oat cultivar Nezlamny during two generations after the seed treatment

2021 ◽  
Vol 29 ◽  
pp. 41-46
Author(s):  
V. A. Katsan ◽  
A.I. Potopalsky ◽  
B.O. Zadorozhnii
Keyword(s):  
Seed Treatment ◽  
First Generation ◽  
Negative Influence ◽  
Stem Growth ◽  
Panicle Length ◽  
Stem Height ◽  
Grain Productivity ◽  
Two Generations ◽  
Negative Effect ◽  
Stimulation Of

Aim. The investigation of the influence of the constituents of Izatison, DMSO and PEG400, on the oat growth and its grain productivity during 2 generations after the seed treatment became the aim of this study for the elucidation of mechanism of Izatison stimulant influence. Methods. The broad scale of the concentrations of the solvents composition in the proportion, to be as in Izatison, was used. The plants were grown in the field. The growth processes were evaluated by the stem height on the tubing stage. The grain productivity was characterized by the panicle length, the grains number in the panicle and of theirs weight. Results. The dependence of influence of the solvents composition on the stem growth from its concentration was detected in the first generation. In some variants the negative influence was revealed on the grains number in the panicle and on theirs weight. The stimulation of the growth regardless from the solvents concentration was observed in the second generation and the more pronounced negative effect on the grain productivity. Conclusions. The solvents DMSO and PEG400 are able to influence on the oat growth and its productivity, and that effect was manifested also in 2 generation after the seed treatment. Keywords: Izatison, DMSO, PEG400, oat growth and grain productivity.

scholarly journals Post-fire management and recovery of a pine forest in Greece

Web Ecology ◽  
2010 ◽  
Vol 10 (1) ◽  
pp. 27-31 ◽  
Author(s):  
I. Spanos ◽  
Y. Raftoyannis ◽  
P. Platis ◽  
E. Xanthopoulou
Keyword(s):  
Woody Plant ◽  
Pinus Halepensis ◽  
Plant Cover ◽  
Woody Species ◽  
Control Site ◽  
Plant Composition ◽  
Northern Greece ◽  
Pine Regeneration ◽  
Negative Effect ◽  
Treatment Application

Abstract. The effects of management after fire in Pinus halepensis forests were assessed in northern Greece. Seeding, logging and building of log barriers were applied in burned sites and compared to a control site. Two years after treatment application, 70–80% of the ground in all sites was covered with vegetation. Seeding with herbaceous plants did not increase plant cover. Logging and building of log barriers negatively affected herbaceous species but increased woody species. During the first spring after fire, the highest numbers of P. halepensis seedlings were observed in the control site and the lowest number in the logged site. Logging and log barrier building had a negative effect on pine regeneration compared to control and seeding treatments. Woody plant composition was similar in control and seeding sites, with dominance of P. halepensis and Cistus species. A different pattern was observed in the logging and log-barrier sites with a low number of seeders and a high number of resprouter species.

scholarly journals ГИС-ПОДХОД ДЛЯ ОЦЕНКИ ВЛИЯНИЯ ОБЫЧНЫХ И СДВОЕННЫХ КОЛЕС НА ТВЕРДОСТЬ ПОЧВЫ

2015 ◽  
Vol 5 (03) ◽  
pp. 73-100
Author(s):  
A. V. Zhukov
Keyword(s):  
Penetration Resistance ◽  
Negative Influence ◽  
Positive Influence ◽  
Cultivated Plants ◽  
Gis Technology ◽  
Negative Effects ◽  
Soil Penetration Resistance ◽  
Surface Character ◽  
Top Soil ◽  
Negative Effect

<p>GIS-APPROACH application has allowed establishing that usual wheels of machine-tractor units carry out considerable influence on soil which exceeds visible borders of a track of wheels on the dimensions. This influence shows in augmentation of soil penetration resistance at 100-155 % in comparison with the control on depth of 0-10 cm and on 20-30 % on depth of 45-50 %. It is impossible to exclude that influence of wheels proceeds more deeply, than tests have been conducted. Critical for cultivated plants value of soil penetration resistance in 3 MPa under the influence of usual wheels of agricultural machinery comes nearer practically to a surface. Character of profile changes of hardness in various regions influences of wheels allows assuming the long season of a relaxation of soil for achievement of background values of soil penetration resistance. The further researches are necessary for an establishment of concrete indicators of dynamics. Negative influence of an overstocking does not confine only deterioration of conditions of growth of assemblages of rootlets of plants. Infringement of processes of moving of moisture in the soil, the accelerated evaporation and the slowed down processes of a filtration and an infiltration, destruction of modular frame, activization of erosive processes is possible. The understanding of these processes will give the chance volume understanding of real influence of running systems of machine-tractor devices on bedrock. Region intensive influence of dual wheels is circumscribed by the top soil layers (0-15 cm). The major feature of influence of dual wheels is absence of an overstocking above critical levels. It is impossible to exclude possible positive influence of moderate inspissations of soil under the influence of dual wheels for growth of agricultural crops and moisture conservation in soil. The cumulative negative effect on soil crossed vehicles traces is probable. The long season of a relaxation of soil after anthropogenic transformation can create a network of traces of vehicles in the field. In region crossings of traces negative effects considerably increase.</p> <p><em>Keywords: hardness of bedrock, GIS-TECHNOLOGY, technique influence</em></p>

scholarly journals The Influence of Enterprise Risk Management, Leverage, Firm Size and Profitability on Firm Value in Property and Real Estate Companies Listed on the Indonesian Stock Exchange in 2016-2018

2021 ◽  
Author(s):  
Dihin Septyanto ◽  
Ikhwan Maulid Nugraha
Keyword(s):  
Risk Management ◽  
Firm Size ◽  
Firm Value ◽  
Stock Exchange ◽  
Descriptive Analysis ◽  
Negative Influence ◽  
Positive Influence ◽  
Enterprise Risk Management ◽  
Enterprise Risk ◽  
Negative Effect

The objective of this study was to analyze the effects of enterprise risk management (ERM) disclosure, leverage, firm size and profitability on firm value, which is proxied by Tobin’s Q. High corporate value can reflect the shareholders’ wealth. This study used the Indonesian Capital Market Directory (ICMD). The sample included 32 companies, chosen with nonprobability purposive sampling. This study used a quantitative approach with descriptive analysis methods and panel data regression to test hypotheses using the Eviews 10 application. ERM disclosure, leverage and profitability had a positive and significant influence on firm value, while firm size had a negative influence on firm value. The implication of this research is that where ERM has a positive influence on firm value, it is good for companies to increase ERM disclosure, because the company will be considered to have managed its risks well. Debt policy variables that are proxied by the Debt to Equity Ratio (DER) and profitability proxied by ROA had a positive effect on firm value. That is, a higher value of DER was followed by an increase in the percentage of Return On Assets (ROA), which increased the firm’s value. However, the company’s size variable which was proxied by Ln Total Assets had a negative effect on the value of the company, which indicated that investors dislike company assets that are too high and that are not offset by high profits. Keywords: enterprise risk management, leverage, firm size, profitability, firm value

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