Impact of Geomorphological Variables in Weighing the Lithological Influence on Geochemical Composition of Stream and Overbank Sediments: A Regression Model for the Zumberak Area (NW Croatia)

The two multiple regression models were compared on the assumption that the geochemical composition of the alluvial material is basically originally derived from the bedrock lithology of a drainage basin of the Zumberak Area (NW Croatia). The latter was integrated with both stream sediment and overbank sediment geochemical data via the two essentially different approaches as regards the catchment basin geomorphological data: (1) as the relative area of influence representing a portion of the catchment basin occupied by a certain rock type; (2) as the relative “line” of influence representing a narrow tract of a certain rock type traversed by the majority of perennial streams which form the active stream network. The model comparison was accomplished on the basis of the goodness-of-fit test for both experimental designs and for the same set of data. The most important result of these experiments highlights the linear approach as the more appropriate model for ascertaining the lithological influence on the analyzed sample media. This can be explained by the stronger erosive and transportational power of the water which flows in the well defined channel network in contrast to the unconcentrated surface runoff in the interfluvial area, coupled with the buffering effects of rich slope and riparian vegetation, which is characteristic of the Zumberak heartland

Geochemical Comparison of Stream and Overbank Sediments: A Case Study from the Zumberak Region, Croatia

Geochemical comparison between the stream and overbank sediments from low- to medium-order drainage basins is grounded on the presupposed statistical contradistinction of their locality-paired sample correlatives. Discriminant analysis differentiated the overbank from stream material mainly on account of higher content of most of the analyzed elements in the former vis-a-vis an otherwise common geochemical semblance. Only the carbonate material seems to be depleted in overbank sediment samples. Investigations also demonstrated that in the relatively non-contaminated area it may be more difficult to verify the supposed purity-contamination reciprocity between the investigated media, since the recent and prehistoric materials were not contrasted as regards their non-lithogenic components

Normalization and Trace Element Contamination of Soils in a Karstic Polje - An Example from the Sinjsko Polje, Croatia

Estimation of the anthropogenic over natural contribution in the chemical content of soils and sediments is very important but not easy to measure. Normalization based on either aluminium or iron, as reference conservative elements having supposed natural distributions, is a useful tool in solving this problem. However, several independent factors can influence the normalization procedure, which if not taken into account could lead to completely erroneous conclusions about the origin of the particular elevated concentrations of certain elements. Therefore, a great deal of caution should be exercised during application of the normalization procedure. Analytical data from 95 soil samples from the Sinjsko polje enabled us to critically apply this procedure. Linear regression analysis, evaluation of enrichment factors and trend surface analysis with the construction of appropriate maps were used to test the procedure. Presuming an existing linear dependence between the conservative element and the heavy metal it is possible with the use of linear regression to simultaneously define the heavy metal geochemical background (baseline) and to isolate natural and/or anthropogenic outliers (anomalies). Coupled with geographic plotting facilities this type of outlier-screening is used to locate areas of man made pollution. Statistical treatment of selected elements included the calculation of means, standard deviations and other estimates of basic statistic parameters. Evaluation of enrichment factors reveals the dependence of this parameter upon four main factors: the choice of reference element; the choice of reference material; the homogeneity of reference element distribution in the study area; and correlation of particular element with reference element. Examination of trends is a common procedure in the analysis of geochemical maps. Its purpose is to segregate the underlying trend that possibly pervades the study area, from the local variations, that is, the “noise” or “background”. Statistical analysis, as suggested by the results in this work, would be more properly used over general areas in the karstic terrain, with different geological, geomorphologic and hydrogeological characteristics, rather than being focused on the relatively small phenomena such as poljes, with many local geologic, hydrogeological and geochemical constraints

Effect of different types and levels of Organic Manures on Yield and Yield Components of Garlic (Allium sativum L) at Kadawa, Kano, Nigeria

Effects of different types and levels of organic manures on the yield and yield components of garlic (ex- Kofa var) was investigated. Two experiments were conducted under irrigation at the Institute for Agriculture Research (I.A.R) Kadawa in the Sudan Savanna zone of Nigeria during 2007/2008 and 2008/2009 (Nov- Mar) dry seasons. The treatments consisted of five levels (0, 2.5, 5.0, 7.5 and 10.0 tons/ha) of three types of organic manures (poultry droppings (P.D), farm yard manure (FYM)and cow dung (CD) laid out in a Randomized Complete Block Design (RCBD) with four replications. Yield parameters studied included cured bulb weight , average bulb diameter, average number of cloves/bulb, average weight of cloves and cured bulb yield (kg/ha). The results showed Significant (P=0.5) effect of all organic manures with highest yield values obtained from poultry droppings, then cow dung and farmyard manure respectively. Increasing levels of all applied manures from 0- 10 tons/ha significantly increased all yield parameters assessed. Thus for optimum yield of garlic at Kadawa, the use of 7.5-10 tons/ha of poultry dropping could be recommended.Keywords: Poultry droppings (PD), Farm yard manure (FYM), Cow dung (CD), Kadawa, Sudan Savanna, Garlic, Irrigation, yield and yield components

Adsorption studies of DNA origami on silicon dioxide

Self-assembled DNA nanostructures promise low-cost ways to create nanoscale shapes. DNA nanostructures can also be used to position particles with nanometer precision. Yet, reliable and low-cost ways of integrating the structures with MEMS technology still have to be developed and innovations are of great interest to the field. We have examined in detail the adherence of DNA origami tiles on silicon oxide surfaces of wafers in dependence on pH-value and magnesium ion concentration. The results of this work will help to pursue new strategies of positioning DNA nanostruc-tures on SiO2. Precise control over the strength of structure-surface adhesion is a prerequisite of relia-ble processes

Analisis Lingkungan Dalam Rumah Dengan Kejadian Asma

Telah dilakukan analisis lanjut data Riset Kesehatan Dasar (Riskesdas) dan Kor Susenas tahun 2007, dengan tujuan untuk mendapatkan variabel-variabel yang berhubungan dengan kejadian Asma. Waktu analisis selama 3 bulan (September sampai dengan Nopember 2008), dengan rancangan analisis deskriptif dan analitik. Analisis bivariat menggunakan uji chi square atau uji Fisher exact, karena semua variabel independen dan dependen berskala kategorik. Nilai kekuatan hubungan dilihat dari nilai ORcrude (Odds Ratio). Terdapat 9 parameter lingkungan dalam rumah dianalisis secara statistik. Parameter tersebut meliputi: bahan berbahaya dan beracun (B3), perilaku merokok dalam rumah, bahan bakar memasak, sumber penerangan, jenis atap, jenis dinding, jenis lantai, kepadatan hunian dan kepemilikan ternak. Hasil analisis 9 parameter faktor lingkungan dalam rumah menunjukkan bahwa ada hubungan bermakna antara 8 parameter lingkungan dalam rumah dengan kejadian asma dengan nilai P<0,05, kecuali kepadatan hunian. Odds ratio terbesar 1,99 untuk bahan bakar memasak dan odds ratio terkecil 0,8 yaitu B3.. Proporsi berisiko terbesar ditunjukkan oleh parameter sumber penerangan sebesar 5,08% dan proporsi terkecil adalah B3 sebesar 3,29%. Melihat besarnya prevalensi Asma, maka Kementerian Kesehatan perlu mengupayakan intervensi untuk menurunkan prevalensi asma tersebut dengan cara pengendalian pencemaran udara dalam rumah. Perlu pula penyuluhan tentang bahaya dari pencemaran udara dalam rumah karena terbukti adanya hubungan antara kualitas udara dalam rumah dengan kejadian Asma. Penelitian lebih lanjut perlu dilakukan dengan menggunakan desain yang dapat membuktikan hubungan kausal antara kualitas udara dalam rumah dengan asma

Geochemical Baseline Mapping of Soils Developed on Diverse Bedrock from Two Regions in Croatia

The comparison of contents and distribution maps for Al, As, Ba, Ca, Co, Cr, Cu, Fe, La, K, Na, Ni, Mg, Mn, P, Pb, Sc, Sr, Ti, Th, V, Y, Zn and Hg in the topsoil cover of two typical regions are given. One is a carbonate bedrock (karst) dominated region (southern Dalmatia) and the other a non-carbonate bedrock dominated region (NW Croatia). The results imply that the soils developed on carbonate bedrock have higher mean values of almost all elements excluding K, Na, Mg and Ba, which are lower in carbonate terrains. In comparison with the non-carbonate terrains, for the carbonate terrains the following elements have higher mean concentrations: Al, As, Co, Cu, Fe, La, Mn, Pb, Ni, Mn, Th, V, Cr, Zn, Zr and Nb, while Sr, P and Ti have similar contents. Approximately 4% of the sites can be considered as moderately enriched (polluted) in Pb, either from mining activities or airborne deposition. Only a limited number of sampling sites can be directly linked with mineralization. The derived factors are usually interpreted as associations of elements that imply a common source or behavior in regard to geogenic or anthropogenic influences. It was found that difference between the northwestern Croatia and southern Dalmatia is not expressed only by concentration differences but also by element associations. Five factor models accounting most of the data variability seemed appropriate to portray the geochemical variability within the topsoil of both region

A Factor Model of the Relationship between Stream Sediment Geochemistry and Adjacent Drainage Basin Lithology, Medvednica Mt., Croatia

A mathematical model is constructed to relate the geochemical composition of recent stream material in a number of catchments on Medvednica Mt. to a broadely defined bedrock lithology which represents the parent material for the former. It is a system based factor model, which synthesizes eight lithological and 25 geochemical variables (major, minor and trace elements), reducing their relationships to six geologically meaningful factors. Five of these divulged a definite relationship between geochemistry and lithology. These are labelled as follows: factor of metamorphic rocks; factor of igneous rocks; factor of Tertiary carbonate rocks; factor of parametamorphic rocks and factor of Mesozoic carbonate rocks. Two lithologies; the Mesozoic clastic rocks and Quaternary sediments showed no clear association to any of the factors. Alternatively, one of the factors (F2) can be identified as “non-lithologic” indicating other, perhaps anthropogenic, contributions to the stream sediment geochemical composition

Recent Sediments of Makirina Cove (Northern Dalmatia, Croatia): Their Origin Viewed Through a Multidisciplinary Approach

Makirina Cove was formed by the Holocene sea-level rise which caused a marine ingression into the depression formed within Albian–Cenomanian dolomites at approximately 4.5 ka B.P. At present, Makirina Cove represents an restricted, stressed, shallow-marine (<2m) ecosystem characterized by varying seawater temperatures (0–35°C) as well as fluctuating salinities (up to 41‰) affected by seasonally enhanced evaporation, continuous freshwater supply through on-shore and submarine springs associated with the coastal karst area and surface run-off episodes. These environmental conditions have been conducive to high primary production of organic matter resulting in the formation of organic-rich deposits which contain up to 5 wt.% of organic carbon. Up to the present times, 3.5 m of sediments have been deposited indicating a relatively high sedimentation rate estimated at 0.75 m/1.0 ka in the northern central part of the Cove. The sediments are being deposited mostly as poorly sorted clayey–sandy silts. The distribution and concentration of most of the chemical elements is dependant on the mineralogical composition and granulometric features of the Makirina sediments, which show values more or less similar to those from the Central Adriatic. Accordingly, there is a positive correlation with Al and K concentrations increasing off-shore and with the depth being associated with increasing concentrations of clay minerals within the clay fraction. The same holds true for concentrations of some trace elements, especially Mo and Se which is consistent with the distribution pattern of sulphides. Selenium is preferentially enriched in authigenic pyrite and it is probably the major source of Se in the Makirina Cove sediments. The concentrations of Ca, Mg and Sr decrease off-shore and they are linked to the composition of the surrounding carbonate rocks. The saturation indices show that the water is supersaturated with respect to carbonates enabling the precipitation of authigenic amorphous or crystalline carbonate phases from the pore water in the upper segment of the sediment column. According to the oxygen isotopic (δ18O) composition, molluscs precipitated their carbonate shells mostly during warmer periods (May to November) at or near isotopic equilibrium with their ambient waters. The carbon isotopic δ13C composition of mollusc carbonate shells is environmentally affected due to oxidation and decomposition of organic matter as well as influxes of fresh water into the Cove, indicating their formation out of the predicted isotopic equilibrium with atmospheric CO2. Palynological and organic carbon isotopic (δ13C) composition shows that the sedimentary organic matter (SOM) is 70–90% lipid- and hydrogen-rich and on average 2/3 marine derived (mainly phytoplankton, bacteria and marine macrophytes) and 1/3 terrestrially derived (mainly woody tissue). The variations in composition of SOM have been noted as a function of the distance from the shore. The type and the preservation state of SOM and pyrite as well as the measurements of Eh, pH, total alkalinity, dissolved inorganic carbon (DIC) and the enrichment of redox-sensitive trace elements, indicate oxygen-depleted depositional conditions and that the sediment is highly reductive even in the uppermost segment at the sediment/water interface. According to the results obtained from the applied methods, the features of Makirina sediments strongly reflect the given depositional conditions within this restricted, stressed, shallow-marine environment where these organic-rich sediments originate, and may therefore serve as a calibration standard in further investigations