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1
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Evaluation of carbon stock in the sediment of two mangrove species, Avicennia marina and Rhizophora mucronata, growing in the Farasan Islands, Saudi Arabia

100%
Eid E. M., Khedher K. M., Ayed H., Arshad M., Moatamed A., Mouldi A.
Oceanologia
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2020
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tom 62
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nr 2
2

Detection of Dirofilaria immitis in mid-Western arid Argentina

84%
Cuervo P. F., Sierra M. R., Waisman V., Gerbeno L., Sidoti L., Albonico F., Mariconti M., Mortarino M., Pepe P., Crigoli G., Genchi C., Rinaldi L.
Acta Parasitologica
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2013
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tom 58
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nr 4
Dirofilariosis, caused by Dirofilaria immitis and D. repens, is (re-) emerging worldwide. Dogs are the main reservoirs, while human infection has recently become an important focus of interest and attention. In Argentina, canine D. immitis infection has been described in eastern and northern subtropical and temperate humid regions, but never reported in mid-western arid regions so far. In this research note we report for the first time the occurrence of autochthonous human and canine D. immitis infection in the region.
3

Key factors in the site selection of Rosa canina (L.) – applying the generalized additive model

84%
Guner S. T., Ozkan K., Comez A.
Polish Journal of Ecology
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2011
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tom 59
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nr 3
Determining suitable sites for species is of great importance in the choice of plant species to be used for ecosystem restoration. The number of plant species to be used in restoration of degraded ecosystems is restricted by climate in arid and semi arid regions. Planting with economically important species in addition to ecological aspects is preferred by decision makers in Mediterrenian countries including Turkey. This study was addressed to determine the significant environmental factors influencing the distribution of dog rose hip (Rosa canina) and to obtain its distribution model. The study was carried out in an area of 26,400 km2 in The Inner Anatolia which has semiarid climate. 106 sample plots, 20 x 20 m in size, were selected from different sites with and without Rosa canina in the summer of 2007. Wilcoxon rank-sum statistic for continuous variables and Pearson Chi-square tests for categorical variables were applied. Altitude, slope degree, available water capacity, soil reaction and soil K, Ca, Mg content as well and total calcium carbonate amount as the continuous variables and northwest- northeast group of aspect, metamorphic group of bedrock as the categorical variables were determined as the significant factors influencing the presence of dog rose. Generalized Additive Model (GAM) was performed for modeling the distribution of the species. To obtain the best model, all significant environmental factors were evaluated. The best model result was obtained (training Area Under Curve (AUC) = 0.902 and cross-validation AUC = 0.841) by means of altitude, slope degree, aspect, and bedrock. Interspecific correlation analysis (ICA) was applied to define indicator species accompanying the dog rose. Dog rose distribution was positively correlated with Cistus laurifolius, Pyrus elaeagnifolia, Lonicera caucasica subsp. orientalis, Quercus vulcanica and Amelanchier rotundifolia subsp. Rotundifolia. The results obtained from this study are crucial for estimation of the suitable areas for Dog rose in restoration studies of natural ecosystems in the Mediterranean region, including Anatolia in Turkey.
4

Species distribution models to estimate the deforested area of Picea crassifolia in arid region recently protected: Qilian Mts. National Natural Reserve (China)

84%
Xu Z., Zhao C., Feng Z.
Polish Journal of Ecology
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2012
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tom 60
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nr 3
The earth is now facing the land degradation due to human disturbance, natural habitats were converted to rural and agricultural areas in order to fulfill the increasing demand of human population. The deforestation of Picea crassifolia (Qinghai spruce) forest at Qilian Mts is an example of such disturbance. P. crassifolia is an ecologically and hydrologically important plant species in the northwestern arid area of China. However, the forests have been intensively and extensively deforested. In order to restore the human-disturbed ecosystems, the spatial distribution of P. crassifolia needs to be delineated. This study employed Genetic Algorithm for Rule-set Prediction model (GARP) and Maximum entropy model (Maxent) and four environmental variables (mean temperature of the warmest quarter, precipitation of the wettest quarter, annual solar radiation, topographic wetness index) to predict the potential distribution of P. crassifolia in Qilian Mts. Genetic Algorithm for Rule-set Prediction model (GARP) produces a model of species niches in geographic space based on heterogeneous rule-sets. Maximum entropy model (Maxent) focuses on fitting a probability distribution for occurrence based on the idea that the best explanation to unknown phenomena will maximize the entropy of the probability distribution, subject to the appropriate constraints. The environmental variables were spatially interpolated throughout the entire study area. We used sensitivity-specificity sum maximum approach to select the threshold value. The projected niche space for the mean temperature of the warmest quarter is between 8.5 and 18.1°C; the space for the precipitation of the wettest quarter is between 149 and 245 mm; the space for annual solar radiation is 118–1100×103 wh m–2 and the space for topographic wetness index is between –0.4 and 5.1. The results show that both GARP and Maxent’s models produce acceptable predictions, but the overall comparison shows that GARP prediction is better than Maxent’s; the comparison between the observed distribution and the predicted distribution suggests that 61% (2869 km2) of P. crassifolia forests have been deforested.
5

Phenology of the alien invasive plant species Prosopis juliflora in arid and semi-arid areas in response to climate variability and some perspectives for Its control in Ethiopia

84%
Shiferaw W., Bekele T., Demissew S., Aynekulu E.
Polish Journal of Ecology
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2020
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tom 68
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nr 1
6

The effect of the halophytic shrub Lycium ruthenicum (Mutt) on selected soil properties of a desert ecosystem in Central Iran

84%
Jalali G. A., Akbarian H., Rhoades C., Yousefzadeh H.
Polish Journal of Ecology
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2012
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tom 60
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nr 4
We compared soil properties beneath naturally-occurring patches of Lycium ruthenicum Murray (fam. Solanaceae) to evaluate the shrub’s potential to improve the fertility of saline soils. Soil pH, total nitrogen and carbon and extractable potassium, magnesium and phosphorus were respectively significantly higher in the A and B horizons of Lycium shrub patches compared to adjacent unvegetated soils. The influence of Lycium on these soil properties increased with shrub density. Total soil N and extractable Mg and K concentrations were 1.8, 2.6- and 6.6-fold higher under dense Lycium shrub patches compared to unvegetated, bare areas and soil pH was 0.5 units higher. In contrast, the presence of shrubs and shrub density had no clear affect on the EC, Na or CEC of the A horizon soils. The shrub effect extended to the gypsum-rich By horizon (20–50 cm depth) and underlying B horizon (30–80 cm depth) for several soil properties. Total soil C and N were 1.8- and 1.6-fold higher beneath dense Lycium patches than bare soil areas. Soil pH remained 0.4 units higher under dense Lycium than bare soil patches. In the B horizon total soil C was twice as high beneath dense Lycium patches compared to the other patch types. Lycium ruthenicum not only tolerates the saline and drought conditions, it also produces sufficient biomass to increase the nutrient and organic matter content of surface mineral soils in this arid ecosystem and may have potential to improve soil conditions, facilitate ecosystem development and slow desertification.
7

Foliar stable carbon isotope discrimination and nutrients contents in two desert plant species

84%
Zhao L., Xiao H., Liu X., Li J., Xiao S.
Polish Journal of Ecology
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2007
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tom 55
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nr 1
Variation of foliar stable Carbon Isotope Discrimination (CID Δ‰) and nutrient contents of Artemisia ordosica (Krasch) (semi-shrub species) and Caragana korshinskii (Kom.) (shrub species) were studied at the southeastern margin of the Tengger Desert, China. Foliar CID Δ, total phosphorus content (TP) and potassium content (K) in A. ordosica were markedly higher than in C. korshinskii while foliar total nitrogen content (TN) and water-use efficiency (WUE) (calculated from foliar CID Δ) in C. korshinskii were significantly higher than those in A. ordosica. There were significant and positive relationships between foliar CID Δ, TN and TP contents (P <0.001) in C. korshinskii, while in A. ordosica a strong and significant positive correlation existed between CID Δ and K content (P <0.001). Based on WUE, TN, TP, and K contents, as well as their relationships, we may conclude that in arid environments, the survival of C. korshinskii profits from its higher WUE, while the survival of A. ordosica from its higher TP and K contents in leaves. In addition, the correlations of foliar CID Δ values with TN and TP contents in C. korshinski and with K content in A. ordosica revealed that the water was one of the main factors limiting the absorption capacity for N and P in C. korshinskii, and for K in A. ordosica. While nutrient conditions were not the factors affecting the growth of C. korshinskii and A. ordosica in the study areas.
8

Variation of sexual and clonal reproduction in Eremosparton songoricum (Litv.) (Fabaceae) on drought in arid regions: an experimental approach

67%
Wang J.-C., Shi X., Yin L.-K., Zhang D.-Y.
Polish Journal of Ecology
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2012
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tom 60
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nr 1
Clonal plants combine sexual and clonal reproduction, which contribute differently to plant fitness. We investigated the consequence of natural selection on the two reproductive modes and the ecological factors that affect the reproductive modes of Eremosparton songoricum (Litv.) Vass. in order to understand the reproductive strategies of a clonal plant and the relationship between sexual and clonal reproduction. Morphological characteristics and biomass allocation patterns were m easured and compared at the clonal fragment level in two natural populations (riverside population A and hinterland population B) in the Gurbantunggut Desert, China. The flowering plant ratio, inflorescence number per plant, flower number per raceme, fruit number, mass of 100 seeds, root biomass, fruit biomass and ramet height were significantly higher, whereas fruit set, ramet density, rhizome biomass and length, and root number were significantly lower, in population A compared with those in population B. We estimated that the importance of clonal reproduction varies in two populations of E. songoricum, and the investment adjustment in the two reproductive modes may be based on cost required for each new plant to generate the more survival progeny in the plant life time.
9

Water requirements of two landscape tree species Prosopis grandulosa [DC] and Conocarpus erectus [L.] grown in arid regions

67%
Moftah A. E., Al-Ghanim W. M.
Polish Journal of Ecology
|
2008
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tom 56
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nr 2
217-226
Six-month-old honey mesquite (Prosopis glandulosa DC) and buttonwood (Conocarpus erectus L.) tree seedlings were grown under different soil water potentials (Ψsoil) in order to determine the minimum soil water potential at which both species can survive and grow fairly well, and to study the soil-plant water relationship at different irrigation regimes. The results showed that growth of Prosopis was not affected significantly until soil water potential was lower than –0.12MPa, while growth of Conocarpus seedlings was affected at water potential of about –0.08MPa, below which, plant height, leaf area and shoot and root dry weights were severely reduced by soil water deficit. Water stress decreased osmotic potential (Ψπ ) of leaves and roots of both species, however the decrease in Ψπ of Conocarpus leaves and roots were much more pronounced (10–15%, resp.) than that of Prosopis. Leaves tended to osmoregulate their cell sap through osmotic adjustment as their content of soluble sugars increased, which occurred in Prosopis at water stress higher than that needed for Conocarpus. The satisfying survival under low Ψsoil could be related to increased osmotic adjustment. Ψsoil values seem to be a more useful tool than the field capacity values to estimate plant water requirements and can be used over an extended period of time, for plant grown under different soil types and different environmental conditions. The study indicates that Conocarpus seedlings can withstand reasonable water stress and can survive at moderately low water potential, but can not be classified as a high drought tolerant or resistant species, while Prosopis can survive at an extremely low water potential and may be classified as a drought tolerant species.
10

Relationship between groundwater depth and pattern of net primary production in oasis-desert ecotone

67%
Wu F.-J., Yu Z.-L., Wei X.-P., Deng J. M., Li T., Zhao C.-M., Wang G.-X.
Polish Journal of Ecology
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2010
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tom 58
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nr 4
Pattern of plant biomass and net primary production was investigated in two localities (Minqin and Linze) of oasis-desert ecotone (ODE) in Northwest China, in order to recognize the spatial and temporal variability of vegetation under same regional climate with different groundwater depth. The average depth to groundwater was over 14.02 m at Minqin -- marked further as DG (deep groundwater) and about 4.96 m at Linze -- marked further as SG (shallow groundwater). We have measured plant biomass and Netprimary productivity (NPP) across species, threetimes per year for three consecutive years, in sixplots along Minqin and Linze oasis-desert ecotone(further marked as DG and SG ODE), respectively.Our results showed that DG and SGODEs had different growth responses to differentgroundwater depths. DG ODE exhibited higherinter-annual variation in annual NPP (rangedfrom 0.18 to 9.30 g m⁻²) than did SG ODE (rangedfrom 0.42 to 17.99 g m⁻²). Decrease of groundwaterdepth had apparently altered the seasonalityof productivity in DG ODE systems, where precipitationin summer maintained plant growth,while ODE with high groundwater depth tendedto have higher spring NPP in SG ODE. Spatialand temporal heterogeneity of NPP at the scaleof our measurements was significantly greater inDG ODE than in SG ODE. SG ODE tended tosupport higher NPP than did DG ODE. In addition,the groundwater depth strongly influenced spatial and temporal heterogeneity of NPP in thedesert ecosystems. Clearly, the desert ecosystemwith higher groundwater depth is more stable andmore resistant to long-term drought or climateshifts in arid regions. These investigations andquantitatively analysis are very significant for theexecution of conservation and restoration in aridecosystems.
11
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Effect of exogenous salicylic acid on the response of snap bean (Phaseolus vulgaris L.) and Jerusalem artichoke (Helianthus tuberosus L.) to drought stress

59%
El-Tohamy W. A. K., El-Abagy H. M., Badr M. A. A., Gruda N.
Acta Scientiarum Polonorum. Hortorum Cultus
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2018
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tom 17
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nr 4
Water shortage is a major problem that limits growth and productivity of plants in arid and semi-arid regions. Protecting plants from adverse environmental conditions by using simple methods could be of great value under these conditions. In the present study, we examined water status and drought tolerance of snap bean, a drought-sensitive plant, and Jerusalem artichoke, a relatively drought tolerant plant in response to the application of salicylic acid (SA). Different levels of SA were applied and several physiological, growth, productivity and quality parameters were recorded together with the relative water content. Foliar application of SA improved growth, productivity, quality as well as some physiological parameters of snap bean and Jerusalem artichoke plants exposed to drought stress. Total chlorophyll content and relative water content were higher in plants treated with SA compared to control plants when subjected to drought stress. The specific responses of snap bean and Jerusalem artichoke to SA under drought stress as well as the possible explanations of the effects of SA are discussed.
12

Effects of salt stress on proline content, expression of delta-1-pyrroline-5-carboxylate synthetase, and activities of catalase and ascorbate peroxidase in transgenic tobacco plants

59%
Razavizadeh R., Ehsanpour A.
Biological Letters
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2009
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tom 46
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nr 2
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