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Wastewater Reuse for Alfalfa Production in the Gaza Strip   总被引:1,自引:0,他引:1  
Geography, population growth, and politics combine to make the Gaza Strip a worst-case scenario for water resource planners. Potable water sources are shrinking while at the same time, the proportion of potable water used for irrigation is increasing. To assess whether water from wastewater treatment plants could be safely used for irrigation, this study collected 51 treated wastewater, 51 sludge, 44 soil, 30 alfalfa, and 24 oranges and lemon samples and analyzed the samples for major and trace elements. Both Inductively Coupled Plasma - Optical Emission Spectroscopy (ICP/OES) and X-ray fluorescence (XRF) were used for the determination of Ag, Al, As, B, Ba, Br, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Na, Ni, P, Pb, Rb, Se, Sr, Zn, Zr, Th, and U in digested and solid samples, respectively. Treated wastewater characteristics showed a very good agreement with the guidelines of many developed countries. Moreover, none of the tested parameters in soil showed concentrations exceeding their corresponding background values. For alfalfa, both ICP/OES and XRF showed Zn concentrations in leaves (36–42 mg/kg, respectively) higher than in root (19–31 mg/kg, respectively). The Cu showed also the same trend as Zn. No significant variation was observed between the concentrations of Cr and Mn in plant parts; concentrations of Co and Pb were two times higher in roots than in leaves and stems. The findings confirm that treated wastewater is safe to use for irrigation in Gaza. Collecting and reclaiming this water can contribute to wise use of each drop of water available.  相似文献   
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Summary Spirogyra gaterslebensis nov. spec.Vegetative cells 18–21 × (88,5-) 109–182 (–223,5) µm, with replicate end walls. 1 Chromatophore, making (4-) 5–6 (–8) turns, rarely 2 Chromatophores with (1,5-) 2 (–3) turns. Conjugation lateral and scalariform; tubes formed ± by both gametangia; fertile cells abruptly inflated to 41,5–52,0 (–70,0) µm in diameter. Zygospores ellipsoid 26,0–34,0–45,0 (–52,0) × 41,5–47,0–78,0 (–96,0) µm; median spore wall yellow, finely punctate, on the poles sometimes with a few wrinkles.In the GDR in a road ditch between Gatersleben and Quedlinburg with shallow, slowly running water, together withVaucheria woroniniana Heering V. debaryana Woronin andV. sessilis (Vauch.) D.C. April–Mai 1967.
. VI.Spirogyra gaterslebensis, Salamacis
Spirogyra gaterslebensis nov. spec. : , Vaucheria woroniniana Heering,V. debaryana Woronin V. sessilis (Vauch.) D. C. 25. IV — 16. V. 1967. . .
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Zusammenfassung Es wird über ein Vorkommen der bisher nur aus China bekannten Süßwasser-RotalgeBatrachospermum intortum Jao 1941 an mehreren Standorten im gebirgigen Osten (Provinz Oriente) der Insel Kuba berichtet. Es dürfte sich um den ersten Nachweis der Gattung für diese Antilleninsel handeln.
ABatrachospermum, Sect. Contorta Skuja from Cuba
Summary Batrachospermum intortum hitherto known only from China, was found on several localities in the mountainous eastern part of Cuba (Prov. Oriente). This may be the first report of the genus for this island.

Batrachospermum Contorta Skuja
Batrachospermum intortum Jao 1941, , . ( ). .


Ergebnisse der 1. Kubanisch-deutschen Alexander von Humboldt-Expedition 1967/68, Nr. 33.  相似文献   
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A study was conducted to determine the extent of genetic diversity among African cassava (Manihot esculenta Crantz) accessions resistant to the cassava mosaic virus disease (CMD), using simple sequence repeat (SSR) markers. The accessions included a breeding stock (clone 58308), five improved lines, 62 CMD resistant and 10 CMD susceptible landraces. Genetic diversity was assessed among accessions in five cluster groups derived from UPGMA analysis on data from 18 SSR primer pairs. Average gene diversity, He, was high in all cluster groups, with an average heterozygosity of 0.591 ± 0.061. The estimator of inbreeding Fis revealed a low level of inbreeding within groups and averaged −0.262 ± 0.142. Gene diversity among all accessions was 51.4% and gene diversity within cluster groups was 46.6%, while 4.8% was due to diversity between the different cluster groups. The amount of genetic differentiation measured by Gst and Fst were 9.6% and 12.1% respectively, indicating a weak genetic structure.  相似文献   
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Zusammenfassung In Algenaufsammlungen aus dem Harzgebiet wurden achtSpirogyra-Arten gefunden, an Freiland- sowie Kulturmaterial untersucht und dabei die Variationsbreite einiger Merkmale durch umfangreiche Messungen geprüft.
On someSpirogyra species of the Harz mountains
Summary Eight species ofSpirogyra found in collections of algae from the Harz mountains were studied on living material from the natural site and on cultures derived from it. Based on numerous measurements, the variability of some characteristics is investigated.

8 Spirogyra. ; .
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