Volume 70, Issue 11

Skeletal soils are not suitable for agriculture, and often are allocated to marginal uses such as cherry orchards for timber production. These require some agricultural practices (irrigation, soil tillage or weed control) which can contribute to the development of a hardpan. Compacted layers can adversely affect timber production, so subsoiling works are required. This study examined the effect of six years of tillage on hardpan formation in a skeletal soil by means of mechanical impedance measurements with a dynamic penetrometer cone (dynamic cone test), a method that is quick and easy to use, but can suffer from interference by stones. Mechanical impedances along the soil profile were measured in four plots differing in tillage (with or without) and drip irrigation (with or without) treatments. Exploratory data analysis together with statistical inference techniques related to linear general models were applied. The presence of a transitional layer on top of the hardpan is suggested in the non-tilled plot and soil depth that can be explored easily by roots has increased by 20 cm.

Plants influence the water regime in soil by both water uptake and an uneven distribution of water infiltration at the soil surface. The latter process is more poorly studied, but it is well known that roots modify soil structure by enhancing aggregation and biopore production. This study used a dye tracer to visualize the impact of plants on water flow in the topsoil of a Greyic Phaeozem. Brilliant blue was ponded to 10 cm height in a 1 m × 1 m frame in the field immediately after harvest of winter wheat (Triticum aestivum L.). After complete infiltration, the staining patterns within the vertical and horizontal field-scale sections were studied. In addition, soil thin sections were made and micromorphological images were used to study soil structure and dye distribution at the microscale. The field-scale sections clearly documented uneven dye penetration into the soil surface, which was influenced by plant presence and in some cases by mechanical compaction of the soil surface. The micromorphological images showed that root activities compress soil and increases the bulk density near the roots (which could be also result of root water uptake and consequent soil adhesion). On the other hand in few cases a preferential flow along the roots was observed.

Aggregate stability is considered to be an appropriate indicator of the relative resistance of soils to detachment by the forces of wind or water. Structural weakness and high rates of erosion in red yellow podzolic (RYP) soils of Matara district are, in general, discussed as prominent problems in intermediate scale agricultural estates. The present study was conducted to ascertain the impacts incurred on the stability of soil aggregates by the alteration of natural forests to agricultural lands, using tea, rubber, and tea/rubber intercropping soils. Surface soils were taken to assess the wet and dry aggregate stabilities, bulk density (Db), clay content, and soil organic carbon (SOC) content. The Db of rubber (1.62 g cm -3 ) and tea/rubber intercropping (1.61 g cm -3 ) soils differed significantly (P < 0.05) from forest (1.33 g cm -3 ) and tea (1.48 g cm -3 ) soils. Rubber and tea/rubber intercropping soils had significantly high clay contents as well. Forest soil had the highest SOC content, whereas tea, tea/rubber, and rubber soils respectively showed 45, 50, and 70% decline. The aggregate size distribution did not differ noticeably in forest, tea, and tea/rubber intercropping soils. However, rubber soils with the least SOC content had a lower percentage of macro-aggregates (> 0.5 mm) and significantly low wet and dry mean weight diameters. Above results revealed that the changes in land use negatively influenced the SOC pool and the stability of aggregates. Significant and consistent relationship between the carbon stocks and the wet and dry stabilities of aggregates has not been noted. It was clear that the content of SOC would not be considered as the solitary factor that affects wet and dry stabilities of aggregates in the tested Rhodudults.

The soil water repellency index, R, is calculated from the ethanol sorptivity, S e , and water sorptivity, S w , using an equation: R = 1.95 S e /S w . In the older method, S e and S w were measured in pairwise arrangements to reduce the influence of spatial heterogeneity of soil properties, and one value of R only was calculated from one pair of S e and S w measurements. The new method to estimate R takes into account all the measured values of water and ethanol sorptivity, i.e., m × n values of R are to be calculated from m values of S w and n values of S e . The results of the t-test revealed that there is not a statistically significant difference between the means of both samples at the 95.0% confidence level for all four studied soils. It was found using the F-test that there is not a statistically significant difference between the variances of samples estimated by the older and new methods at the 95.0% confidence level for all but one (grassland soil) studied soils. Comparison of R values taken in sandy soil under different vegetation cover in Sekule, southwest Slovakia, revealed that the average values of R estimated using the new method increased with vegetation succession, i.e., Pure sand < Glade soil < Grassland soil < Pine-forest soil, while the me|an values of R, estimated using the older method changed in the order: Pure sand < Grassland soil < Glade soil < Pine-forest soil. It seems that an increase in the number of R values processed can result in the more reliable mean values of R at the sites with high spatial heterogeneity of soil properties.

Water storage and flow in soils are highly dependent on soil structure, which strongly determines soil porosity. However pore size distribution can be derived from soil water retention curve (SWRC). Structural characteristics of cultivated arable fields (693 soil profiles, 1773 samples) and soils covered by treated forest stands (137 soil profiles, 405 samples) were selected from the MARTHA Hungarian soil physical database, and evaluated for expressing organic matter effects on soil structure and water retention. For this purpose the normalized pore size distribution curves were determined for the selected soils, plus the modal suction (MS) corresponding to the most frequent pore size class of the soil. Skewness of soils’ pore size distribution curves are found different. The quasi-normal distribution of sandy soils are transformed into distorted in clayey soils. A general growing trend of MS with the ever finer soil texture was shown. Sandy soils have the lowest average MS values, i.e. the highest most frequent equivalent pore diameter. Silty clay and clay soil textures are characterized by the highest MS values. A slight effect of land use and organic matter content is also observable in different MS values of soils under forest vegetation (’forest’) and cultivated arable land (‘plough fields’). MS values of the two land uses were compared statistically. The results of the analyses show that certain soil group’s MS are significantly different under forest vegetation and cultivation. However this difference can be explained only partly and indirectly by the organic matter of different plant coverage in the land use types.

The non-equilibrium water flow was studied on an aeolian sandy soil under grass using the dye tracer infiltration experiments. Two experiments simulating infiltration of 20 mm and 70 mm of rain water were conducted. The improved digital image analysis technique for estimating the effective cross section (ECS) and degree of preferential flow (DPF) from stained soil profiles was used to analyze the depth dependency and variation of the ECS and DPF parameters. It was found that the heterogeneity of water flow in sandy soil under grass increased with depth. Extremes of heterogeneity parameters (minimum value of the ECS and maximum value of the DPF) were almost the same for the two cumulative infiltrations, and the depth, in which the extremes of heterogeneity parameters occurred, increased with an increase in cumulative infiltration. Moreover, considerable variation of infiltration patterns was indentified in consecutive vertical sections.

Spatial heterogeneity of soil hydrophysical properties was estimated in 2 fallow sandy soils at Csólyospálos and Örbottyán, Hungary. Significant differences in small particle (= silt + clay) content (5.0% vs. 13.7%), organic matter content (1.62% vs. 0.91%), and CaCO 3 content (3.1% vs. 5.1%) measured at Csólyospálos and Örbottyán, respectively, resulted in a higher persistence of water repellency in the Csólyospálos soil. It also resulted in a significantly higher water sorptivity and hydraulic conductivity of the Örbottyán soil. The spatial heterogeneity of soil hydrophysical properties was significant reaching 3 orders of magnitude differences due to the variances of soil properties. The water repellency cessation time was inversely related to the hydraulic conductivity and water sorptivity at Csólyospálos site.

The effects of vegetation at different succession stages on soil properties and water flow were assessed in sandy soil at 3 experimental sites near Sekule village (southwest Slovakia). Site S1 was a pioneer site dominated by mosses, site S2 was an early successional stage with a thin stand of grasses, and site S3 was an early successional stage (more advanced compared to the previous), richer in species, with a denser stand of grasses. It was found that vegetation at different succession stages affected soil properties and water flow in sandy soil, but the order of changes in some soil properties and water penetration depths were different from the order of succession stages.

Water repellence is a condition in which soils become hydrophobic and do not readily absorb water. The condition causes problems in agricultural production relating to water availability for seed germination and plant growth. In this research we assess the impact of disturbing the soil by a single annual soil tillage (compared with no-till) and crop residue retention (compared with residue removal by burning) on the severity of water repellency, and on water infiltration during and immediately after rainfall, for 5 discrete rainfall events over an 18-month period covering two crop growing seasons. Soil tillage and crop residue removal were associated with decreased severity of water repellency. Despite this, soil tillage resulted in less infiltration of rain water, especially in the crop inter-row spaces, one hour after the commencement of rainfall, and 6 hours after the conclusion of rainfall. Where a single soil tillage was performed, soil in the inter-row spaces absorbed 19-30% of incident rainfall, compared with 58-78% in undisturbed soils. This was observed for a rainfall event 11 months after soil tillage, indicating that soil tillage has a long-lasting impact on pathways of water entry into the soil.

Night-time leaf wetting process was analyzed in relation to micrometeorological conditions in a semi-arid cornfield and its effect was examined in the following morning with reference to the leaf-to-air humidity gradient which is a driving force in transpiration. Leaf wetness occurred due to dew formation under clear and calm night conditions which decreased canopy surface temperature to the air dew-point temperature. The amount of dew on leaves collected around sunrise (06:00) was 26.4-104.3 g m −2 · leaf area, which corresponded to 0.07-0.27 mm water. Leaf wetness remained until around 10:00 and significantly decreased leaf temperature. As a result, the leaf-to-air humidity gradient also decreased in the wetted leaf compared to the non-wetted leaf. These results suggest that night-time leaf wetting induces lower transpiration rate and may play a role in diminishing plant water stress due to excess transpirational water loss in the morning in semi-arid environments. Further studies are needed in order to demonstrate this possible effect.

In this study, two new species of Hoplophthiracarus (Acari: Oribatida: Phthiracaridae) from China are described, Hoplophthiracarus fujianensis sp. n. and Hoplophthiracarus longqiensis sp. n. A key to known Chinese species of Hoplophthiracarus is provided.

A new species of oribatid mite of the genus Trhypochthoniellus (Oribatida: Trhypochthoniidae) is described from mosses in a swamp of vicinity of Punta Arenas, Chile. Trhypochthoniellus chilensis sp. n. differs from all species of the genus by the presence of monodactylous legs and notogastral setae p3, clearly greater distance between c 1 -c 1 than d 1 -d 1 and three pairs of setae on epimeres IV. Comparative morphological analysis of the species and a revised diagnosis of the genus are presented.

Three new species of oribatid mites (Acari: Oribatida), Austrachipteria novazealandica sp. n. (Achipteriidae), Cultroribula otagoensis sp. n. (Astegistidae) and Microlamellarea minuta sp. n. (Lamellareidae), are described from New Zealand. The family Lamellareidae and the genus Microlamellarea are recorded for the first time in the fauna of this country. Austrachipteria novazealandica sp. n. is morphologically most similar to A. bidentata (Hammer, 1967), but differs from the latter by shorter interlamellar and bothridial setae and by posteriorly concave notogaster. Cultroribula otagoensis sp. n. is morphologically most similar to C. bicuspidata Mahunka, 1978, C. castriensis Mahunka, 1985, C. tropica Balogh, 1958 and C. zicsii Balogh & Mahunka, 1981, but differs from all listed species by lamellae being separated medially. Microlamellarea minuta sp. n. differs from two known species of the genus, M. coetzeeae Mahunka & Mahunka-Papp, 2011 and M. engelbrechti Coetzee, 1987, by the presence of minute interlamellar setae, leaf-shaped rostral setae and two pairs of anal setae. An identification key to known species of Microlamellarea is presented. Transfer of the genus Cultroribella from Astegistidae to Lamellareidae is proposed.

The genus Apterogyna Latreille, 1809 is reviewed from Saudi Arabia based on specimens collected from Rawdhat Farshet Sheaal (Al-Aflag), Rawdhat Al-Harmalyiah (Al-Quwayiyah), Ibex Reserve National Park (Hutet Beni Tamem) and Shada Al-Ala Mountain (Al-Baha). Two Apterogyna species were previously recorded from Saudi Arabia: A. mateui Giner Marí, 1945 and A. olivieri Latreille, 1809. A new species, A. shadaensis Soliman & Gadallah sp. n. (Al-Baha) is described and illustrated and a new record, A. similis Soliman & Gadallah, 2015 (Al-Aflag) is discovered. An illustrated key of four Saudi Arabian species of Apterogyna is given.

Large areas of montane forests are commercially harvested, while some other parts remain unmanaged. These conditions provide an opportunity to study the response of bird communities to forest management. Here we focused on the effects of tree species composition and tree age on bird species richness. We counted birds in two types of montane forest (beech and mixed) replicated in three age classes (managed 55-65 years, managed 85-95 years, unmanaged over 200 years) in the Vtačnik Mountains, Slovakia. Number of bird species at individual study sites (local richness) was predicted solely by the tree age and not by the forest type. Specifically, the number of species was highest in the oldest stands, while the stands of 55-65 and 85-95 years did not differ from each other. By contrast, forest type seems important for total bird species richness (number of species recorded in all study sites of a given type) with more species recorded in mixed forests than in beech forests. The local richness seems thus limited by the amount resources available at a given site, which is highest in the oldest stands irrespective to forest type, probably due to largest amount of food, dead wood or tree cavities, being particularly suitable for habitat specialists. However, larger species pool in mixed forest, enriched by birds adapted to coniferous trees, increases the total number of species observed in this type. We thus recommend to shift the harvest to the highest possible age and to include some other tree species into parts of beech monocultures.

The pineal hormone melatonin plays an important role in immunomodulation of avian species. These im­munomodulatory effects of melatonin are known to be mediated by three membrane bound receptors found in birds, Mel 1a , Mel 1b and Mel 1c - However, specific involvement of these receptors in mediating immunomodulatory effects of melatonin in Lung Associated Immune System (LAIS) remains unexplored till date. The aim of the present study was to check the specific melatonin receptor subtype involved in regulation of LAIS. For this purpose, we used luzindole, a non selective and 4P-PDOT, a selective Mel 1b receptor antagonist under in vitro condition to assess their specific potency towards melatonin induced cellular immunity in the lung tissue of Perdicula asiatica. Melatonin enhanced proliferation of lymphocytes isolated from lung tissue and up-regulated both receptor types (Mel 1a and Mel 1b ) on physiological doses while higher doses decreased the proliferation and down regulated the expression of both receptors. Luzindole decreased proliferation of lung lymphocytes and down-regulated the expression of both receptors in a dose dependent manner while 4P-PDOT decreased proliferation of lymphocytes isolated from lung and down-regulated the expression of Mel 1b receptor subtype only. Proliferation rate of lymphocytes isolated from lung tissue followed more the expression pattern of Mel 1b than the Mel 1a . Thus, we may suggest that Mel 1b might be involved in cell mediated immunity in lung of P. asiatica to a greater extent than Mel 1a .

Roosts are a very important resource for bats, and often play a central role in conservation projects. To evaluate the feasibility of identifying urban bat roosts, we trapped 30 individual bats from seven species, attached radio transmitters and located their daytime roosts. This enabled us to build hypothesis on the importance of trees and buildings as daytime roosts for urban bats. None of the captured animals were reproducing or lactating, so we assumed all recorded roosts to be simple daytime roosts. Of the 30 marked bats, 18 individuals (six species) could be monitored, and a total of 114 roosts were located; 57 of which were in trees, and another 57 in buildings. Our results indicate that neither building condition nor green coverage in the immediate (≤ 20 m) surroundings of a building was a significant predictor for the presence of roosts in or on a building. For tree roosts, diameter at breast height (DBH) was the most important factor determining the choice of tree roosts, but was found insignificant in a Generalized Linear Mixed Model. We presume that the lack of significance regarding green coverage and DBH in the model can be explained by the limited sample size of our study.