Herstellung wasserdichter Karten     

Fritz Dittmer 《Forstwissenschaftliches Centralblatt》1910,32(1):61-62

Ohne Zusammenfassung  相似文献   

Wirkungen der einzelnen Hilfspflanzen in den nordostbayerischen KrüppelbestÄnden     

Regierungsforstrat und UniversitÄtsdozenten Dr. Fritz Ernst 《European Journal of Forest Research》1937,59(4):105-122

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Effect of mass selection for seed density in populations derived from Avena abyssinica x A. sativa amphidecaploids     

S. E. Fritz  M. E. Sorrells 《Euphytica》1990,46(1):85-93

Summary Seed of two heterogeneous amphidecaploid Avena populations (NY79143 and NY79148) were separated into three groups based on seed density using a commercial gravity table. Bulk populations were evaluated in a field trial to test the effect of selection for seed density on agronomic characteristics, while chromosome behavior was studied on similarly selected individual plants grown in a coldframe. Selection for seed density was associated with improved agronomic characteristics for individual plants grown in coldframes but the treatment effect was not significant in the field trial. Population and treatment effects were significant for chromosome number. Mean chromosome numbers were higher in NY79148 than in NY79143, and increased with selection for seed density. Populations did not differ for mean somatic instability but did show interactive population^*treatment effects. Several generations of selection for seed density is suggested.  相似文献   

Environmental Impacts of Acid Leachate Derived from Coal-Storage Piles upon Groundwater     

Cook  Angie M.  Fritz  Steven J. 《Water, air, and soil pollution》2002,135(1-4):371-388

Leachate emanating from a coal-storage area at an electricutility plant in Northwest Indiana (U.S.A.) is impacting groundwater quality. This assessment is based on results of along-term groundwater monitoring program conducted at Purdue University's Wade Utility Plant where a monthly average of 32,000metric tons of both high- and low-sulfur coal are stored. Groundwater from both a perched and major aquifer (the WabashValley Aquifer) as well as surface water from a large retentionpond were sampled monthly for 34 consecutive months. Such a long-term, continuous sampling scheme proved beneficial in identifying seasonal trends and anomalies within the chemistryof ground- and surface waters. Data show elevated concentrationsof sulfate and hardness in the perched zones and the WabashValley Aquifer (WVA). Lead in the WVA has also been reported ata concentration greater than the state maximum contaminant level, while several metals (Be, Cd, Cu, Pb, Ni, Se, and Zn) containedwithin retention-pond sediments have the highest concentrationsin aquatic sediments ever reported within the State of Indiana.Due to the buffering capacity of carbonate minerals in underlyingunconsolidated deposits, the acidic pH of coal-pile leachate is raised to values typical for groundwater in carbonate terrain common in Northwest Indiana. Further ameliorating the input of acid percolation is the dilution capabilities of both the WVA and the recharge pond. Hence, sites without such advantages would exhibit a greater degree of groundwater contamination than what is observed at Purdue's coal-storage facility.  相似文献   

Ferripolyphosphate-whey protein powders. Their potential as nutritional iron supplements.     

S B Jones  E B Kalan  T C Jones  J F Hazel  L F Edmondson  A N Booth  J C Fritz 《Journal of agricultural and food chemistry》1975,23(5):981-984

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Subject Area ´Sediments´: The Subject Editors and Advisors: Challenges and relevant literature in JSS and ESPR (the presentation of the Editors is not complete yet and will be continued). This part is published online only and will appear in No. 1, 2007     

Thomas Knacker  Fritz Frimmel  Jan Schwarzbauer  Marc Babut  Henner Hollert  Philip Owens  Kay Hamer 《Journal of Soils and Sediments》2006,6(4):268-268

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The history of South American tropical precipitation for the past 25,000 years   总被引：1，自引：0，他引：1  

Baker PA  Seltzer GO  Fritz SC  Dunbar RB  Grove MJ  Tapia PM  Cross SL  Rowe HD  Broda JP 《Science (New York, N.Y.)》2001,291(5504):640-643

Long sediment cores recovered from the deep portions of Lake Titicaca are used to reconstruct the precipitation history of tropical South America for the past 25,000 years. Lake Titicaca was a deep, fresh, and continuously overflowing lake during the last glacial stage, from before 25,000 to 15,000 calibrated years before the present (cal yr B.P.), signifying that during the last glacial maximum (LGM), the Altiplano of Bolivia and Peru and much of the Amazon basin were wetter than today. The LGM in this part of the Andes is dated at 21,000 cal yr B.P., approximately coincident with the global LGM. Maximum aridity and lowest lake level occurred in the early and middle Holocene (8000 to 5500 cal yr B.P.) during a time of low summer insolation. Today, rising levels of Lake Titicaca and wet conditions in Amazonia are correlated with anomalously cold sea-surface temperatures in the northern equatorial Atlantic. Likewise, during the deglacial and Holocene periods, there were several millennial-scale wet phases on the Altiplano and in Amazonia that coincided with anomalously cold periods in the equatorial and high-latitude North Atlantic, such as the Younger Dryas.  相似文献   

Succession of arbuscular mycorrhizal communities in the foreland of the retreating Morteratsch glacier in the Central Alps     

Fritz Oehl  David Schneider  Ewald Sieverding  Conradin A. Burga 《Pedobiologia》2011,54(5-6):321-331

The development of communities of arbuscular mycorrhizal fungi (AMF) was investigated in the subalpine foreland of the glacier Morteratsch located at approx. 1900–2100 m a.s.l. near Pontresina (Engiadin’ Ota, Switzerland). In particular, we asked if the succession of AMF communities follows or precedes the primary plant succession, and we checked the mycorrhizal status of the pioneer plant Epilobium fleischeri. Soil samples were taken at pioneer and dense grassland sites established during the last hundred years representing different periods of glacier retreat: 1875–1900, 1940–1950, 1970–1980 and 1990–2000. Extraradical hyphal length densities and AMF spore populations were analyzed in soil samples. Spore formation and mycorrhizal root colonization were monitored in trap cultures grown on Trifolium pratense, Lolium perenne, Plantago lanceolata and Hieracium pilosella or on E. fleischeri over 14 months. We found that E. fleischeri is strongly arbuscular mycorrhizal, but plants in closest distance to the glacier (glacier retreat in the last 4–6 years before sampling) were non-mycorrhizal. Spore densities and root colonization in trap cultures were generally low in samples from glacier stage 1990–2000. Highest spore density and colonization were found for the sites ice-free since 1970–1980, whilst highest AMF species richness and hyphal length densities were found at the sites ice-free since 1875–1900. Our findings show an establishment of a few AMF pioneer species (e.g. Diversispora versiformis and Acaulospora punctata) within 5–10 years and species rich AMF communities at sites ice-free for 100 years (28 species). Their succession generally follows the succession of the plant communities. We conclude that AMF pioneer species might be mainly distributed by wind transport while other AMF fungi (e.g. Glomus rubiforme and Glomus aureum) rather need a below-ground hyphal network to invade new areas.  相似文献   

X-ray Pulsar in the Crab Nebula     

Fritz G  Henry RC  Meekins JF  Chubb TA  Friedman H 《Science (New York, N.Y.)》1969,164(3880):709-712

X-ray pulsations have been observed in the Crab Nebula at a frequency closely matching the radio and optical pulsations. About 5 percent of the total x-ray power of the nebula appears in the pulsed component. The x-ray pulsations have the form of a main pulse and an interpulse separated by about 12 milliseconds.  相似文献   

Early warming of tropical South America at the last glacial-interglacial transition     

Seltzer GO  Rodbell DT  Baker PA  Fritz SC  Tapia PM  Rowe HD  Dunbar RB 《Science (New York, N.Y.)》2002,296(5573):1685-1686

Glaciation in the humid tropical Andes is a sensitive indicator of mean annual temperature. Here, we present sedimentological data from lakes beyond the glacial limit in the tropical Andes indicating that deglaciation from the Last Glacial Maximum led substantial warming at high northern latitudes. Deglaciation from glacial maximum positions at Lake Titicaca, Peru/Bolivia (16 degrees S), and Lake Junin, Peru (11 degrees S), occurred 22,000 to 19,500 calendar years before the present, several thousand years before the B?lling-Aller?d warming of the Northern Hemisphere and deglaciation of the Sierra Nevada, United States (36.5 degrees to 38 degrees N). The tropical Andes deglaciated while climatic conditions remained regionally wet, which reflects the dominant control of mean annual temperature on tropical glaciation.  相似文献