Reconstruction of the Holocene vegetation in the central Negev Desert,Israel, on the basis of palynological data on the Atzmaut zoogenic deposit

Zoogenic deposits are among a few promising sources of information on the history of arid ecosystems. To reconstruct the former vegetation of the Negev Desert, we performed palynological analysis of the Atzmaut zoogenic deposit that had been formed over the past 6000 years. The results made it possible to reveal seasonality in the use of this rockshelter, to reconstruct the dynamics of vegetation, and to estimate the effect of climatic changes and livestock grazing on the vegetation in the central part of the Negev Desert.     

Nitrogen, phosphorus, and potassium uptake by wheat and their distribution in soil following successive, annual compost applications

The overall objective of the present study was to determine the loading limits of composts that should be applied annually to irrigated wheat. We conducted a container experiment in a greenhouse during four years. It included eight treatments: sewage sludge compost (SSC) and cattle manure compost (CMC), each applied annually to a sandy soil, at rates equivalent to 3, 6, and 12 kg m(-2), and two controls, one fertilized and one unfertilized. Total dry matter (DM), grain production, and the amount of N, P, and K taken up by plants increased with increasing compost rate. Nitrogen uptake by the plants of the fertilized control was much higher than by the plants of the highest compost rate. Phosphorus and K uptake by the plants amended with the highest compost rate was much higher than by the fertilized control plants. Inorganic N quantity in the soil increased with increasing compost rate and with successive applications. The net N mineralization during the first year of wheat growth was very low, less than 3.5% of the applied organic N under all compost application rates. The contribution of the organic N mineralization increased during the second and third years. Most of the N increase in the compost treatment was found in the upper layer of 0 to 15 cm, whereas in the fertilized treatment N accumulated from the surface to the bottom of the container, 0 to 55 cm. The successive application of high rates of composts resulted in P and K accumulation in the soil profile.     

Application of geoaccumulation index and enrichment factor for assessing metal contamination in the sediments of Kafrain Dam, Jordan

An investigation is reported of the degree of metal pollution in the sediments of Kafrain Dam and the origin of these metals. Fourteen sampling sites located at Kafrain Dam were chosen for collecting the surface, cutbank, and dam bank sediment samples. The sediment samples have been subjected to a total digestion technique and analyzed by atomic absorption spectrometer for metals including Pb, Zn, Cd, Ni, Co, Cr, Cu, Mn, and Fe. XRD analyses indicate that the sediments of Kafrain Dam are mainly composed of calcite, dolomite, quartz, orthoclase, microcline, kaolinite, and illite reflecting the geology of the study area. The enrichment factor (EF) and geoaccumulation index (I _geo) have been calculated and the relative contamination levels assessed in the study area. The calculations of I _geo are found to be more reliable than of those of EF. The enrichment of metals in the study area has been observed to be relatively high. I _geo results reveal that the study area is not contaminated with respect to Ni, Co, Cr, Cu, and Mn; moderately to strongly contaminated with Pb; and strongly to extremely contaminated with Cd and Zn. The high contents of Pb, Cd, and Zn in the study area result from anthropogenic activities in the catchment area of the dam site. These sources mainly include the agricultural activities, sewage discharging from various sources within the study area (effluent of wastewater treatment plants, treated and untreated wastewaters, and irrigation return water), and the several industries located in the area. Degrees of correlations among the various metals in the study area are suggested by the results and the intermetallic relationship.     

Pierre robin sequence associated with amniotic band syndrome ultrasonographic diagnosis and pathogenesis

A case of prenatal diagnosis of the Pierre Robin sequence is reported in which hydramnios and amniotic bands are present. The possible pathogenesis is discussed.     

Broadcast urea reduces N2O but increases NO emissions compared with conventional and shallow-applied anhydrous ammonia in a coarse-textured soil

Despite the importance of anhydrous ammonia (AA) and urea as nitrogen (N) fertilizer sources in the United States, there have been few direct comparisons of their effects on soil nitrous oxide (NO) and nitric oxide (NO) emissions. We compared N oxide emissions, yields, and N fertilizer recovery efficiency (NFRE) in a corn ( L.) production system that used three different fertilizer practices: urea that was broadcast and incorporated (BU) and AA that was injected at a conventional depth (0.20 m) (AAc) and at a shallower depth (0.10 m) (AAs). Averaged over 2 yr in an irrigated loamy sand in Minnesota, growing season NO emissions increased in the order BU < AAc < AAs. In contrast, NO emissions were greater with BU than with AAc or AAs. Emissions of NO ranged from 0.5 to 1.4 kg N ha (50-140 g N Mg grain), while NO emissions ranged from 0.2 to 0.7 kg N ha (20-70 g N Mg grain). Emissions of total N oxides (NO + NO) increased in the order AAc < BU < AAs. Despite having the greatest emissions of NO and total N oxides, the AAs treatment had greater NFRE compared with the AAc treatment. These results provide additional evidence that AA emits more NO, but less NO, than broadcast urea and show that practices to reduce NO emissions do not always improve N use efficiency.     

Preserving the maritime cultural heritage of the Mediterranean,a cradle of cultures,religions and civilizations—the holy land perspective

The article presents the main ancient marine sites of the Holy Land, points the endangered sites and the needed preservation activities. The ancient cultural heritage existing on the Mediterranean shores reflect important events in the history of humanity. It represents numerous important cultures, religions and traditions. This coastal and underwater heritage is rapidly eroded due to sea level rise, global changes and rapid coastal development. Actions taken by the state of Israel to rescue, protect and preserve the marine cultural heritage include: underwater rescue surveys, coastal erosion monitoring, risk assessment surveys and pilot projects for protecting and preserving the sea front of the antique sites at Akko, Apollonia and Ashkelon. Israel proposes that the Mediterranean and European countries will establish a collaborative project aimed at mapping the cultural recourses and establishing master plans for the protection and preservation of the marine and coastal cultural heritage of the Mediterranean.     

Uranium decay products found on Mir space blanket mitt

The space blanket mitt which covered the Trek detector on Mir during four years of orbital flight has been measured for gamma radiation with HPGe and multidimensional spectrometers. Difference spectra from very-long-period spectrometer runs on the mitt and on a similar non-deployed mitt from the same manufacturer show that the mitt has acquired small but significant amounts of gamma radioactivity during orbital flight. Twelve gamma-ray peaks have been measured in the difference spectra, including peaks identified as due to 214Bi and 214Pb from the uranium-radium alpha decay series, and others possibly due to the uranium-actinium series. This implies the presence of a sparse population of uranium decay products in lower orbital space which can only have come from nuclear explosions, burned-up satellite nuclear batteries, the solar wind, or supernova fragments in the local interstellar medium.     

Phosphorus leaching at cold temperatures as affected by wastewater application and soil phosphorus levels

Land application of wastewater in the northern-tier United States during winter months has been suggested as a means to reduce cost of building storage lagoons. A study was initiated in 1996 to assess land application of potato-processing wastewater on a 120-ha field at Park Rapids, MN. One objective of this study was to evaluate the effects of soil P levels and temperature on P leaching in soil columns. In this paper, we report the P sorption, desorption, and leaching characteristics of a high-P (>200 mg kg(-1)) and a low-P (<25 mg kg(-1)) surface soil from the wastewater irrigation site. The leaching experiment was done with wastewater at 4 +/- 2 or 10 +/- 2 degrees C. The high-P soil resulted in an equilibrium P concentration of 8.0 mg L(-1) compared with 0.14 mg L(-1) for the low-P soil. When low-P wastewater was applied to the high-P soil, the soil acted as a P source, and the total phosphorus (TP) concentration in the leachate was 3.5 times higher than the input TP concentration (C0). When high-P wastewater was applied to the high-P soil, the soil acted as a P sink retarding the TP concentration in the leachate by 80%. Phosphorus desorption was higher at 10 degrees C compared with 4 degrees C. The results showed that depending on P levels of the soil and the wastewater, reduction or increase in leachate P will occur below the surface soil. However, further mobility of this P under field conditions will depend on the volume and rate of percolating water as well as the sorption-desorption characteristics of the subsoil.