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Interactive effects of flooding and treefall gap formation on terra firme forest and várzea forest seed and seedling mechanisms and tolerances in the Ecuadorean Amazon
No full textThe influence of white-water flooding and treefall gap formation on terra firme forest regeneration was investigated in Yasuni National Park of western Ecuador. I set up seed traps, collected seed rain and soil samples, and set out seeds and seedlings in unflooded terra firme forest (dry) and its gaps, and in nearby white-water floodplain várzea forest (wet) and its gaps. I found that (1) total number of dispersed seeds was greatest in the dry gaps with more seeds and greater richness in the gaps than the forest for both forest types, (2) the greatest number of seedlings germinated from wet gap soils with the least from the dry forest with gaps having more seedlings compared to their respective forests, (3) on average 30% of seeds remained after two weeks in the field and species seed losses were significantly different in all but one of the four sites, (4) more large seeds than small seeds were lost to pathogens and those losses were greater in the forests than the gaps, (5) as seed mass increased seedlings survival rates also increased but growth rates declined, and (6) more seedlings survived in gaps compared to closed forests where they grew faster with a larger leaf area ratio. Past sampling has shown that species composition differed between forest types, and present results show that the greatest seed and seedlings losses and the slowest growth rates were in intact terra firme forest, there were medium losses and medium growth rates in terra firme gaps and in the intact várzea forest, and the smallest losses and fastest growth rates were found in várzea gaps
Comparison of soil parameters of the carbon and nitrogen cycles in a long-term fertilization field experiment
No full textIn a long-term fertilization field experiment set up in Debrecen-Látókép in 1983 on calcareous chernozem soil the changes in the chemical and microbiological characteristics related to the carbon and nitrogen cycles of the soil are shown and evaluated. The soil samples were taken in the 26th and 27th years of the experiment, (in 2009, 2010) from maize monoculture and tri-culture. In addition to the effects of fertilizer doses, correlations among soil chemical and microbiological properties were established; and the various ratios among some microbiological parameters were also evaluated.The elements of NPK fertilizers increased together with the doses, so the elements’ effect cannot be separated, the minimum factor is not identifiable.With increasing fertilizer doses, the soil pH decreased in both the mono- and triculture, parallelly there was a significant increase in hydrolytic acidity. A close negative correlation was proved between the pH(H2O) and hydrolytic acidity and pH(KCl) and hydrolytic acidity. An increased soil nutrient content was recorded in each NPK treatment, the available phosphorus and nitrate content increased in a higher proportion than that of potassium.Among the measured parameters of the carbon and nitrogen cycles fertilization had a positive influence on the organic carbon (OC), organic nitrogen (ON), microbial biomass carbon (MBC), microbial biomass nitrogen (MBN) contents, the number of cellulose decomposing and nitrifying bacteria, the nitrate exploration and CO2-production, while it mainly had negative effects on the investigated enzymes (saccharase and urease) activity.Evaluating the ratios among the measured parameters, fertilization seems to have promoted the increase in nitrogen-containing organic compounds, because the OC/ON and MBC/MBN ratios decreased due to the effect of different doses of NPK fertilizers in both cultures
Detecting soil microbial activity via an electrochemical activity sensor
No full textIn water quality research the interest in online biofilm monitoring techniques has recently increased significantly. Christiani et al. (2008) presented a simple electrochemical technique to monitor electro-active biofilm in soil, based on the cathodic polarisation of stainless steel electrodes. Authors present an improved method, in which stainless steel was replaced by copper. By using copper-zinc electrodes authors have shown difference in the electrical potential between sterilized and native soils even at low moisture content
Sand grain mineralogy and morphology under forest and grassland/arable fields in Eastern Hungary
No full textRelated to ongoing (re)forestation in the Great Hungarian Plain the short-term influence of changing land cover was studied on the grains of skeletal sandy soils. In three sampling areas with forest and grassy/arable control plots, the 0.1–0.2 mm grain size fraction of samples taken every 20 cm from the 0–100 cm sandy soil layer (totalling 22,509 grains) were separated and described with optical mineralogical microscope. In order to distinguish sand grains of forest-covered and control areas (grassland/arable land), the results of mineralogical and morphological observations were compared. It was revealed that the amount of feldspar grains is 8–9 times less than the amount of the quartz ones. The increase in the quartz/feldspar (q/fp) ratio is tied to the “consumption” of feldspars: the intense consumption of potassium by trees. Under the forest-covered fields, the number of in-situ crushed grains increased. Grains with etch pits are frequent in samples from the grasslands (except in Hajdúsámson). In samples of forest-covered areas a greatly increased number of brown grains with limonite and/or humus films were observed. The gained results can be useful in proving earlier land use in forested fields
Sulphate and chloride salt efflorescences and their relationships with groundwaters and soils in Hungary
No full textThe aim of the present study is a better understanding of the distribution and formation of salt efflorescences by mineralogical examination. Dominant sodium sulphate and sodium chloride surface efflorescences were selected for investigation. 24 samples were collected between 1999 and 2005 from 16 sites. The soil types were solonchak and meadow solonetz.Basic soil and groundwater analyses were performed according to the standard methods. Minerals were determined by X-ray diffractometry and SEM combined with microanalysis. The evaporation experiments were carried out in a Sanyo Versatile 350 HT environmental test chamber.It was concluded that common sulphate salts form rare and unique mineral associations on salt affected soils in Hungary.Comparing the groundwater compositions and the mineral associations of surface efflorescences or that of precipitated evaporites of groundwaters, the conclusion can be drawn that groundwater composition is reflected much better by the mineral association of experimentally precipitated evaporates of the groundwater than by the mineral associations of surface efflorescences. These differences suggest that the soil matrix may have an effect on the crystallization of minerals (e.g. gypsum, thenardite) in the efflorescences. The differences also suggest that in the surface efflorescences the precipitation process does not come to the end in all cases (minerals with high solubility are missing).Concerning the data on groundwater level depths in case of different (sodium carbonate versus sodium sulphate and sodium chloride) efflorescences, there is a tendency of declining groundwater table in the sequence of these soils. This difference can be explained by the difference (increase) in the solubility of various salt minerals.It was recognized that the change in the major component of surface efflorescenes in time (i.e. the sodium carbonate and sodium carbonate chloride versus sodium sulphate efflorescences before and after 1998) can be explained by the decline of the groundwater level and by the decreasing hydromorphic influence in the lowland area during the 19th and 20th century.Finally it can be stated that the presented research — which mainly focused on mineralogical aspects — has contributed to the earlier knowledge on surface salt efflorescences, which was based only on their chemical composition
Távérzékelés a talajtérképezésben – Szemle – | Remote sensing in soil mapping — A review
No full textA távérzékeléses eljárásokkal gyűjtött információk számos módon hasznosultak, hasznosulnak a talajtérképezésben. A légi fotók és műholdképek megfelelő alaptérképet és térbeli keretet nyújtanak a talajtérképezéshez. A távérzékelt adatok közvetlen, illetve közvetett információt szolgáltatnak az egyes talajtulajdonságokról. Ezáltal mindkét módon támogatni tudják a talajok térbeli változékonyságát leíró két alapvető koncepciót: az objektum alapút, illetve a talajtulajdonságok folytonos térbeli változását hangsúlyozót. Cikkünkben ezen kategorizálás mentén, többé-kevésbé időrendi sorrendet is megtartva, tekintettük át röviden és példákkal illusztrálva, hogy konkrétan milyen formában képes a távérzékelés segítséget nyújtani a talajtérképezés kérdéseinek megoldásában, illetve kivitelezésének gyakorlatában. A távérzékelés által szolgáltatott térben folytonos és kvantitatív adatok megfelelő támogatást nyújtanak a pontszerűnek tekinthető talajtani mérések térbeli kiterjesztéséhez. A távérzékelés sokrétű lehetőséget biztosít a talaj-táj kapcsolatának modellezésére, illetve az ezen alapuló térképezési koncepció számára. A távérzékelésből származó több időpontú spektrális, illetve egyes speciális kiértékelések során előállított felszínborítási, földhasználati térképek, valamint domborzati modellek a digitális talajtérképezés számára a legalapvetőbb környezeti segédváltozókat szolgáltatják. Mindezeken túl a távérzékelt képek hatékonyan támogatják a térképezéseket megelőző mintavétel tervezést és megújították a digitális formában publikált térképek alaptérképi környezetét is. A távérzékelés a közeljövőben is dinamikusan növekvő mennyiségű adatot fog szolgáltatni a földfelszínről. Az ebben rejlő lehetőséget semmiképpen sem szabad elszalasztani a talajtérképezésben érdekelteknek, főképpen a távérzékeléssel nyert adatmennyiséggel összehasonlítva igen csak szűkösen keletkező és elérhető talajtani információ tükrében. A támogatás tehát adott, annak kihasználása azonban már rajtunk múlik.
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Information collected with remote sensing technology has been utilized in soil mapping in numerous ways. Aerial photos and satellite images provide proper base maps and spatial framework for soil mapping. Remotely sensed data give both direct and indirect information on various soil features, thus supporting the two basic concepts applied for the characterization of the spatial variability of soils, one of which is objectbased and the other emphasizing the continuous variation of soil properties. The present paper briefly reviews how remote sensing can provide concrete aid in solving the problems posed by soil mapping and by its application in practice, illustrating this with examples. The spatially continuous and quantitative data provided by remote sensing give adequate support for the spatial extension of location-based soil measurements. Remote sensing provides multiple possibilities for the modelling of soil-landscape relationships and for the mapping concept based on these models. The multi-temporal and multispectral images, the land use or land cover maps and the digital elevation models elaborated on the basis of remotely sensed information provide the most relevant environmental auxiliary data sets used in digital soil mapping. Additionally, images originating from Earth Observation platforms provide an efficient basis for the sample design that precedes soil mapping, and have also created a new base map environment for digitally published novel soil maps. Remote sensing will continue to supply a dynamically increasing quantity of data on the surface of the Earth. Those interested in soil mapping should not let the opportunities latent in this technique pass, especially in the light of the significantly smaller quantity of data originating from soil science research. The possibilities exist, but their utilization depends on us
Komposztkijuttatás hatása az ökológiai módon termesztett almafák (Malus domestica Borkh.) levelének száraz anyag- és Ca-tartalmára | Effect of soil compost application on the dry matter and Ca contents of the leaves in an organic apple (Malus domestica Borkh.) orchard
No full textÖkológiai termesztésű almaültetvényben eltérő komposztadagok (0, 10, 25 és 50 kg N·ha−1) hatását vizsgáltuk a talaj tápelemtartalmának változására (0–30 és 30–60 cm-es mélységben). Mértük az egyes almafajták (Golden Delicious és Pinova) levelének szárazanyag- és Ca-tartalmát, továbbá vizsgáltuk e paraméterek alakulásának egymáshoz való viszonyát.A szabadföldi kísérletet a Debreceni Egyetem Kertészettudományi Intézetének Pallagi Kísérleti Telepén, a talaj- és növényminták analízisét az Agrokémiai és Talajtani Intézet laboratóriumaiban végeztük.A 2011. és 2012. évi eredményeket összevetve lényeges csökkenés mutatkozott a talaj AL-oldható P-tartalmában. Az évek múlásával jelentősen nőtt azonban a talajban a nitrát-, ammónia-, szerves-N és CaCl2-Mg tartalom a kijuttatott komposztadagok hatására. Az AL-K, -Ca, -Mg, a CaCl2-P, -K mennyisége és a pH közel azonosnak mondható.Az első kísérleti évben (2010-ben) még nem volt hatása a komposztnak. 2011-ben már észleltünk hatást, de a fagykár miatt nem volt termés a fákon. 2012-ben a nagy termésterhelés mellett is növekedést tapasztaltunk a szárazanyag-tartalom alakulásában mind a Golden Delicious, mind a Pinova fajták esetében. Adott kezeléseken belül az eltérő termésmennyiségekkel, továbbá az évjárattal összefüggő tendenciákat fedeztünk fel. A rendkívül csapadékos évben (2010) alacsony, míg az aszályos évben (2012) nagy szárazanyag-tartalom értékeket mértünk a levélben. A Golden Delicious és a Pinova esetében kapott tendencia fajtától, kezelés- és termesztés-technológiától függetlenül hasonló.A komposzt hatására 2010-ben a Golden Delicious leveleiben kismértékű, a Pinova leveleiben szignifikáns Ca-tartalombeli növekedést mértünk. Az évjárat hatásáról elmondható, hogy csapadékos évben a szakirodalmi adatoknál magasabb, míg száraz, terméshiányos évben alacsonyabb Ca-tartalommal számolhattunk. Bár a Ca-szintek alakulása tendenciájában megegyezett a két almafajta esetében, mégis megállapítható, hogy a Pinova leveleinek elemtartalma nagyobb volt, mint a Golden Delicious fáké.A levelek szárazanyag-tartalma és Ca-tartalma között fordított arányosságot bizonyítottunk.
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The effect of different compost doses (N active ingredients: 0, 10, 25 and 50 kg·ha−1) on the nutrient contents of the soil (at depths of 0–30 and 30–60 cm) was studied in an organic apple orchard. The dry matter and Ca contents of the leaves were determined for the apple species Golden Delicious and Pinova, and the relationship between these parameters was studied.The field experiments were conducted at the Experimental Station of the University of Debrecen in Pallag. Prior to compost application (April–May) and harvesting (September) soil samples were taken from depths of 0–30 and 30–60 cm with a handheld drill, while leaf samples were taken from three trees in each treatment prior to harvest. The soil and plant samples were analyzed in the laboratories of the Institute of Agricultural Chemistry and Soil Science.The results for 2011 and 2012 revealed a significant decrease in the AL-soluble P contents of the soil. However, the CaCl2-soluble nitrate, ammonia, organic-N and Mg contents of the soil increased over the years as an effect of the applied compost doses, while neither the AL-K, -Ca, -Mg and CaCl2-P, -K quantities nor the pH changed significantly.In the first year (2010) the compost treatments had no effect. In 2011 the positive effect of the compost could be observed, but there was no fruit on the trees due to frost damage. In 2012, in spite of the high fruit load, the dry matter content increased for both Golden Delicious and Pinova. Various trends were observed in relation to the yields recorded within each treatment and in the individual years. The dry matter contents in the leaves were low in the extremely wet year (2010) and high in the dry year (2012). The tendencies were similar for both Golden Delicious and Pinova irrespective of the variety, treatment and cultivation technology.In 2010 the compost treatment increased the leaf Ca contents slightly in Golden Delicious and significantly in Pinova. In the rainy year the Ca contents were found to be higher than the data in the literature, while in the dry year, when no fruit were formed, they were lower. Although the changes in Ca levels showed the same trend for both varieties, the leaf element contents of Pinova were higher than those of Golden Delicious.The dry matter content was inversely proportional to the Ca content of the apple leaves
Study of carD gene sequence in clinical isolates of Mycobacterium tuberculosis
No full textMycobacterium tuberculosis growth rate is closely coupled to rRNA transcription which is regulated through carD gene. The aim of this study was to determine the sequence of carD gene in drug susceptible and resistant clinical isolates of M. tuberculosis and designing of a PCR assay based on carD sequence for rapid detection of this bacterium.Specific primers for amplification of carD gene were carefully designed, so that whole sequence of gene could be amplified; therefore primers were positioned at the upstream (promoter of this gene and ispD gene) and downstream (in ispD gene). DNA from 41 clinical isolates of M. tuberculosis with different pattern of drug resistance was used in the study. PCR conditions and annealing temperature were designed by means of online programs. PCR products were sequenced by ABI system.PCR product of carD gene was a 524 bp fragment. This method could detect all resistant and susceptible strains of M. tuberculosis. The size of amplified fragment was similar in all investigated samples. Sequence analysis showed that there was similar sequence in all of our isolates therefore probably this gene is considered to be conservative. Translation of nucleotide mode to amino acids was showed that TRCF domain in N-terminal of protein CarD was found to be fully conservative.This is the first study on the sequence of carD gene in clinical isolates of M. tuberculosis. This conservative gene is recommended for use as a target for designing of suitable inhibitors as anti-tuberculosis drug because its importance for life of MTB. In the other hand, a PCR detection method based on detection of carD gene was recommended for rapid detection in routine test
