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  1. 6 Polish Journal of Ecology

  2. 4 International Agrophysics

  3. 3 Zeszyty Problemowe Postępów Nauk Rolniczych

  4. 1 Acta Agrophysica. Rozprawy i Monografie

  5. 1 Acta Physiologiae Plantarum

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  1. 2 Skierucha W.

  2. 1 Agostinni F.

  3. 1 Allington G.

  4. 1 Atilgan A.

  5. 1 Bako A.

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  1. 2 2016

  2. 1 2015

  3. 2 2014

  4. 2 2013

  5. 3 2012

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

Temperature effects in soil water content determined with time domain reflectometry

100%
Halbertsma J., van den Elsen E., Bohl H., Skierucha W.
Zeszyty Problemowe Postępów Nauk Rolniczych
|
1996
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tom 436
The relative permittivity of water decreases with increasing temperature. Therefore, it is likely that the soil water content determined with time domain reflectometry (TDR) is influenced by temperature. We derived a correction based on a refractive mixing model. Our field experiment on a peat soil and laboratory experiments on disturbed sand and loam samples showed that there exist significant temperature effects. The magnitude of these effects is a function of water content and temperature. Both the refractive mixing model-based correction and Ledieu’s correction compensated temperature effects reasonable well. We recommend Ledieu’s correction for its simplicity: only information of the soil temperature is needed to correct the measured water content. The model-based correction needs additional information of the TDR calibration function. Our laboratory experiments on disturbed clay samples however, did not show a temperature effect. We suggest that the electrical conductivity counteracts the temperature effects in clay.
2

Altitude patterns of leaf carbon isotope composition in a subtropical monsoon forest

75%
Pan S., Zhang W., Zhao M., Li Y., Xu S., Wang G.
Polish Journal of Ecology
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2016
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tom 64
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nr 2
Leaf carbon isotope composition (δ¹³C) of both vascular and non-vascular plants were investigated in order to assess their variability along an altitude gradient (414, 620, 850, 1086,1286 and 1462 m) from a subtropical monsoon forest located at Mt. Tianmu Reserve, eastern China. Leaf δ¹³C values of all plant species ranged from -34.4 to -26.6‰, with an average of -29.8‰. There is no significant difference in leaf δ¹³C between vascular plants and mosses, however, trees had significantly higher δ¹³C values than herbs. For pooled data, leaf δ¹³C was positively correlated with altitude. Leaf δ¹³C was significantly and negatively correlated with annual mean temperature and atmospheric pressure, while it was significantly and positively correlated with soil water content. Furthermore, there was no relationship between leaf δ¹³C and soil nitrogen content or soil phosphorus content. The altitudinal trend in leaf δ¹³C is the consequence of the interaction between temperature, atmospheric pressure and soil water content.
3
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Distribution of soil water content in cultivated fields based on the measurements by gravimetric and reflectometric methods

75%
Usowicz B., Kossowski J.
Zeszyty Problemowe Postępów Nauk Rolniczych
|
1996
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tom 436
The topsoil (1 - 6 cm) water content measured by gravimetric and reflectometric methods (TDR) in fields with different crops (556 pairs of data) were analysed. Mean values of the topsoil water content in the individual fields as measured by means of the TDR method differed from the measurement by the gravimetric method by from 1 to 14 %. Differences in the coefficients of variability were up to 35 %. The correlation coefficient for all the results of the two methods was 0.889 and the mean square error - 2.4 x 10⁻² m³ m⁻³. However, in the case of individual fields the correlation coefficients were lower. It can be gathered from the analyses carried out that the TDR method yielded satisfactory results when the soil water content was higher than 0.17 m³ m⁻³, and the soil bulk density was about 1.35 Mg m⁻³. Spatial distribution of soil water content obtained from the two methods were generally speaking, similar, however significant differences appeared locally as well. In the fields with lower soil bulk density (in average values) and showed higher differentiation, the values of soil water content as measured by the TDR and its spatial differentiation was higher than the one measured by the gravimetric method.
4

Changes in soil organic carbon and its density fractions after shrub-planting for desertification control

75%
Liu J.-B., Zhang Y.-Q., Wu B., Qin S.-G., Lai Z.-R.
Polish Journal of Ecology
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2014
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tom 62
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nr 2
Planting shrubs on sand land and degraded pasture are two main measures for desertification control particularly in northwest China. However, their effects on soil organic carbon (SOC) and its fractions remain uncertain. We assessed the changes in stocks of SOC, light fraction of SOC (LF–SOC) and heavy fraction of SOC (HF–SOC) after planting Artemisia ordosica (AO, 17 years), Astragalus mongolicum (AM, 5 years) and Salix psammophila (SP, 16 years) in sand land and planting Caragana microphylla (CM, 24 years) on degraded pasture. Results show that: 1) after planting AO, AM and SP on sand land, SOC stocks increased by 162.5%, 45.2% and 70.8%, respectively, and LF–SOC accounted for a large proportion in the increased SOC. Dry weights of LF–SOC, rather than carbon concentrations, were higher in shrublands than that in sand land; 2) after planting CM on degraded pasture, SOC stock decreased by 9.3% and all the loss was HF–SOC in 60–100 cm soil layer where both herbaceous fine root biomass (HFRB) and soil water content (SWC) also decreased. The results indicate that planting shrubs can result in an increase of SOC in sand land, whereas that can lead to a decrease of SOC in degraded pasture. The increase of SOC in sand land mainly bases on the accumulation of dry weight of LF–SOC. The loss of SOC in degraded pasture is caused by the decrease of carbon concentrations of HF–SOC, which can be related to the reduction of HFRB and SWC in deep soil layer. Therefore, shrub-planting for desertification control not always improve the quantity and stability of SOC in northwest China.
5
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Effects of different soil water content on biological nitrogen fixation at soybean

75%
Coskan A., Oz H., Atilgan A.
Infrastruktura i Ekologia Terenów Wiejskich
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2013
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nr 1/III
Biological nitrogen fixation (BNF) is the process that provides organic nitrogenous compounds to the plants by using molecular nitrogen in atmosphere. Higher plants are not capable to use molecular nitrogen in atmosphere as a nitrogen source to generate essential proteins. Therefore plants either should be fertilized by adequate nitrogenous fertilizers or the microorganisms which are capable to produce nitrogenase should provide nitrogen to the plants by BNF. From among a number of factors affecting BNF, soil moisture content and ambient temperatures are considerably effective on the fixation rate. Therefore the global warming would be dramatically defective on BNF, thus effects of soil moisture as well as soil and ambient temperatures on BNF should evaluate prior rising temperature. A pot experiment was carried out to determine the effects of soil water contents on BNF. Four different soil water contents (%25, %50, %75 and %100 of water holding capacity) were adjusted either every 3 days or just after plants indicate wilting point. Non-inoculated pots were added to experiment as a control. The results revealed that BNF is affected by different level of soil water content. The mechanism of this effect would not be the direct effect of water, but the side effect of water on soil oxygen content; therefore, an aeration capability.
6
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Temporal stability of electrical conductivity in a sandy soil

75%
Pedrera-Parrilla A., Brevik E. C., Giraldez J. V., Vanderlinden K.
International Agrophysics
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2016
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tom 30
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nr 3
7
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Comparison of correlation models for the estimation of the water retention characteristics of soil

75%
Walczak R., Witkowska-Walczak B., Slawinski C.
International Agrophysics
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2002
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tom 16
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nr 1
8

Decomposition of fine woody debris from main tree species in lowland oak forests

63%
Ostrogovic M. Z., Marjanovic H., Balenovic I., Sever K., Jazbec A.
Polish Journal of Ecology
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2015
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tom 63
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nr 2
Decomposition is an important carbon flux that must be accounted for in estimates of forest ecosystem carbon balance. Aim of this research is to provide estimate of fine woody debris decomposition rates for different tree species and sample sizes also taking into account the influence of specific microsite meteorological conditions on decomposition rates. In this paper we present results of the first two years of the experiment designed to last six years. Study was conducted in managed lowland oak forest in central Croatia. Decomposition rates (k) of fine woody debris (diameter 0.5–7 cm) for four species (Querus robur L., Carpinut betulus L., Alnus glutinosa Gaernt., Fraxinus angustifolia L.) in four size classes were estimated using litter bag method and mass loss equation of Olson (1963). Overall average k in our study was 0.182 ± 0.011 year-1. Results indicate that decomposition rate is affected by the size of the debris, with the smallest diameter branches (<1 cm) decomposing is significantly faster (k = 0.260 ± 0.018, P <0.05) than the larger one. Tree species from which debris had originated also affected decomposition, although to a lesser extent, with hornbeam samples having significantly (P <0.05) higher average decomposition rate (0.229 ± 0.028), compared to that of ash samples (0.141 ± 0.022). Proportion of variability in k explained by variables ‘species’ and ‘size class’ was assessed with general linear model (R² = 0.644) also taking into account variables like soil temperature and soil water content. Sample size class explained 22.2%; species explained only 9.4%, while soil water content and temperature combined explained 32.8% of the variance of k. Rate constants obtained within this study might be useful in modelling ecosystem carbon balance for similar lowland forest ecosystems in Europe.
9

Influence of moisture and salinity of soil on its dielectric permittivity

63%
Wilczek A., Skierucha W., Szyplowska A.
Acta Agrophysica. Rozprawy i Monografie
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2011
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nr 6[197]
10

Soil water content evaluation and modeling in small catchment with agricultural use

63%
Jurik L., Kaletova T., Halaszova K., Bako A., Ochmanova L.
Acta Scientiarum Polonorum. Formatio Circumiectus
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2013
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tom 12
|
nr 3
Due to extreme consequences of drought and flood in soil and landscape is necessary to know hydrological balance and soil water content. We used historical data about discharge, weather and crops from years 1974–1994, as well as measurements of soil moisture in the forest and arable soil, in grassland and Salix viminalis L. According to this information, the baseflow (by ABSCAN), surface runoff (SCS method), water retention and soil water content were calculated and evaluated.
11

Irrigation management by means of soil moisture sensor technologies

63%
Cepuder P., Nolz R.
Journal of Water and Land Development
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2007
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nr 11
12

The effect of plant mulches on soil moisture in vegetable cultivation

63%
Zaniewicz-Bajkowska A., Kosterna E., Rosa R., Franczuk J.
Electronic Journal of Polish Agricultural Universities. Series: Horticulture
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2012
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tom 15
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nr 2
13
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Procedure to control hydraulic potential variation in soil microcosms

63%
Agostinni F., Shmidt C. S., Mullins C. E., Leifert C.
International Agrophysics
|
2009
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tom 23
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nr 3
215-227
14

Life history strategy influences biomass allocation in response to limiting nutrients and water in an arid system

63%
Mao W., Allington G., Li Y.-L., Zhang T.-H., Zhao X.-Y., Wang S.-K.
Polish Journal of Ecology
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2012
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tom 60
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nr 3
The optimal partitioning theory (OPT) predicts that a plant should allocate relatively more biomass to the organs that acquire the most limiting resource. However, variation in biomass allocation among plant parts can also occur as a plant grows in size. As an alternative approach, allometric biomass partitioning theory (APT) asserts that plants should trade off their biomass between roots, stems and leaves, and this approach can minimize bias when comparing biomass allocation patterns by accounting for plant size in the analysis. We analyzed the biomass allocation strategy of the two species: annual Setaria viridis (L.) Beauv and perennial Pennisetum centrasiaticum Tzvel from the Horqin Sandy Land of northern China by treating them with different availabilities of soil nutrient and water (added in summer and winter), and hypothesized that the two species have different patterns of biomass allocation strategy in response to different soil water content and soil nitrogen content. After taking plant size into account, the biomass allocation strategy of S. viridis and P. centrasiaticum differed in response to nitrogen and water; leaves and root:shoot ratio (RTS) of S. viridis were “true” in response to various soil nitrogen contents. The plasticity of roots was also “true” in response to fluctuation in soil water content. However, P. centrasiaticum showed a different pattern with no shift of biomass allocation strategy in response to nitrogen and water. Adjustment in organs biomass allocation pattern of S. viridis in response to nitrogen and water limitation was dramatic, this suggested that S. viridis support optimal partitioning theory (OPT). P. centrasiaticum has better tolerance to varied environments and more likely support the allometric biomass partitioning theory (APT), this characteristic may allow P. centrasiaticum to keep dominance in fragile habitats.
15
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

The model investigation of soil water content and soil water potential impact on radiation temperature of meadow plant cover

63%
Mazurek W., Walczak R. T., Sobczuk H. A., Baranowski P.
Zeszyty Problemowe Postępów Nauk Rolniczych
|
1996
|
tom 436
The purpose of the study was to find the relation between soil water condition and radiation temperature of meadow vegetation. During the experiment, performed in precisely controlled laboratory conditions, AGA Thermovision System 680 was used for measuring the radiation temperature. The natural meadow plant cover growing on mineral and organic soils taken into the pots was the object of the investigation. The watering of pots was performed in such a way that to get 8 different soil moisture levels. There exist boundary values of soil water content below which the increase of radiation temperature begins. They are 45 % for the organic soil and 15 % for mineral soil. However these values of soil water content correspond to the same soil water potential of about 15 bars. The increase of radiation temperature indicates the limit of the accessibility of soil water for the root system rather than the concentration of water in the soil.
16

Effect of calcium chloride and Arbolin 038 on response of Impatiens walleriana to soil water deficit

51%
Lukaszewska A., Kutnik K., Chylinski W.
Annals of Warsaw University of Life Sciences - SGGW. Horticulture and Landscape Architecture
|
2007
|
tom 28
17

Altitudinal variability of the soil water content in natural and managed beech [Fagus sylvatica L.] forests

51%
Pichler V., Durkovic J., Capuliak J., Pichlerova M.
Polish Journal of Ecology
|
2009
|
tom 57
|
nr 2
313-319
European beech (Fagus sylvatica L.) ranks as one of the most adaptive species among European indigenous trees. Variable interactions between the trees and soil water depend on both phenotypic plasticity of the species and natural conditions. They are controlled through stomatal regulation and the ability of beech trees to accelerate quickly their growth if available resources increase. However, the effect of forest density at various altitudes on the soil water content in beech stands has been studied rather scarcely. Therefore, we monitored soil moisture by means of Time Domain Reflectometry in series of natural and managed stands located on sites representing the lower altitude (200–550 m a.s.l.), middle altitude (550–1050 m a.s.l.) and higher altitude (1050–1300 m a.s.l.) zones of the natural beech belt in the Western Carpathians, Slovakia. Forest stand density, expressed in terms of basal area, i.e. the sum of cross section areas of the tree stems at 1.30 m height, was unchanged in natural stands, but it was reduced by 60% in the shelterwood stands. In the clear-cuts, all trees were removed. Total soil water content (SWC) under forest stands was calculated in mm as the product of soil moisture and soil depth, the latter acquired by electrical resistivity tomography. SWC differences between natural and shelterwood stands of the lower altitude, middle altitude and higher altitude zones averaged 18 mm, 36 mm and –3 mm, respectively. According to the Friedman test on ranks, followed by post-hoc multiple comparison testing, the difference was only significant within the middle altitude zone. In it, soil water consumption by the natural stand was limited only by the hormonally controlled seasonal regulation. The comparatively low water loss in the shelterwood stand resulted from a small rainfall interception by forest canopy and a decreased soil water uptake due to reduced basal area, leaf area index and simple age-size forest structure. In the lower altitude zone, the precipitation deficit and limited extractability of soil water were responsible for the absence of larger SWC differences. As opposed to that, low potential evapotranspiration prevented any noticeable SWC differences within the higher altitude zone.
18

Field validation of DNDC and SWAP models for temperature and water content of loamy and sandy loam Spodosols

51%
Balashov E., Buchkina N., Rizhiya E., Farkas C.
International Agrophysics
|
2014
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tom 28
|
nr 2
The objectives of the research were to: fulfil the preliminary assessment of the sensitivity of the soil, water, atmosphere, and plant and denitrification and decomposition models to variations of climate variables based on the existing soil database; validate the soil, water, atmosphere, and plant and denitrification and decomposition modelled outcomes against measured records for soil temperature and water content. The statistical analyses were conducted by the sensitivity analysis, Nash-Sutcliffe efficiency coefficients and root mean square error using measured and modelled variables during three growing seasons. Results of sensitivity analysis demonstrated that: soil temperatures predicted by the soil, water, atmosphere, and plant model showed a more reliable sensitivity to the variations of input air temperatures; soil water content predicted by the denitrification and decomposition model had a better reliability in the sensitivity to daily precipitation changes. The root mean square errors and Nash-Sutcliffe efficiency coefficients demonstrated that: the soil, water, atmosphere, and plant model had a better efficiency in predicting seasonal dynamics of soil temperatures than the denitrification and decomposition model; and among two studied models, the denitrification and decomposition model showed a better capability in predicting the seasonal dynamics of soil water content.
19

The effect of low or high soil water content on the root system architecture of triticale and maize seedling

51%
Grzesiak M. T., Skoczowski A., Rzepka A., Grzesiak S.
Acta Physiologiae Plantarum
|
2007
|
tom 29
|
nr 1 Suppl.
20

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

51%
Wang J.-C., Shi X., Yin L.-K., Zhang D.-Y.
Polish Journal of Ecology
|
2012
|
tom 60
|
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.
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