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51.
T. Schmitt Druct Yusftattung Schüpler Tabricius und Karl Suebenguth 《Forstwissenschaftliches Centralblatt》1921,43(2):69-79
Ohne Zusammenfassung 相似文献
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Human-wildlife conflict in the Kingdom of Bhutan: Patterns of livestock predation by large mammalian carnivores 总被引:1,自引:0,他引:1
We examined predation activity throughout Bhutan by tiger (Panthera tigris), common leopard (Panthera pardus), snow leopard (Uncia uncia) and Himalayan black bear (Ursus thibetanus) on a variety of livestock types using data gathered over the first two years (2003-2005) of a compensation scheme for livestock losses. One thousand three hundred and seventy five kills were documented, with leopards killing significantly more livestock (70% of all kills), than tigers (19%), bears (8%) and snow leopards (2%). About 50% of livestock killing were of cattle, and about 33% were of horses, with tigers, leopards and snow leopards killing a significantly greater proportion of horses than predicted from availability. Examination of cattle kills showed that leopards killed a significantly greater proportion of smaller prey (e.g., calves), whereas tigers killed a significantly greater proportion of larger prey (e.g., bulls). Overall, livestock predation was greatest in summer and autumn which corresponded with a peak in cropping agriculture; livestock are turned out to pasture and forest during the cropping season, and subsequently, are less well guarded than at other times. Across Bhutan, high horse density and low cattle and yak density were associated with high rates of livestock attack, but no relationship was found with forest cover or human population density. Several northern districts were identified as ‘predation hotspots’, where proportions of livestock lost to predation were considerable, and the ratio of reported kills to relative abundance of livestock was high. Implications of our findings for mitigating livestock losses and for conserving large carnivores in Bhutan are discussed. 相似文献
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OBJECTIVE: To determine if screw loosening in triple pelvic osteotomies (TPO) is minimized when screws cranial to the ilial osteotomy had maximal sacral purchase. STUDY DESIGN: Prospective study. ANIMALS: Forty-six dogs with decreased acetabular coverage of the femoral head and minimal degenerative joint changes. METHODS: TPOs were performed where screws cranial to the ilial osteotomy were inserted to maximally engage sacral bone. Data collected were: use of ilial and ischial cerclage wire, screw length, ventrodorsal radiographic sacral width (most caudal aspect), pelvic canal diameter, and sacral penetration of the 3 cranial screws. On all subsequent radiographs, changes in screw position, pelvic canal diameter, and sacral purchase were noted. RESULTS: For 69 TPOs, 414 screws were used. Mean radiographic cranial screw length was 34.54 mm. Combined sacral depth of all 3 screws was 93.3% of sacral width. All osteotomies healed uneventfully. Twenty-four screws (6%) loosened with 12 being in the most cranial positions. Use of ischial or ilial cerclage wires did not statistically influence screw loosening. Pelvic diameter decreased by a mean of 7.79% from postoperative radiographs to the last radiographic recheck. CONCLUSIONS: By sufficiently engaging the sacrum with screws cranial to the ilial osteotomy, implant failures can be avoided and screw loosening minimized when a 6-hole TPO plate is used. CLINICAL RELEVANCE: To minimize screw-loosening in TPO, screws inserted cranial to the ilial osteotomy should be inserted to maximum sacral depth without penetrating the vertebral canal. 相似文献
56.
Pietro Perrino G. Battista Polignano Karl Hammer Christian O. Lehmann 《Genetic Resources and Crop Evolution》1984,32(4):197-206
Summary The mission was carried out within the Mediterranean Programme of the IBPGR in April/May 1983 with participants from the Socialist People's Libyan Arab Jamahiriya (Agricultural Research Centre, Tarabulus), the Istituto del Germoplasma, Bari, and the Zentralinstitut für Genetik und Kulturpflanzenforschung, Gatersleben. In Tripolitania, the Fezzan- and Ghadmis-areas 316 samples, mostly cereals and vegetables, have been collected. In Tripolitania and the Ghadmis-area the land-races have been nearly completely replaced by new varieties. In the Fezzan genetic erosion is in progress. There, several cereal- and vegetable-land-races could still be collected. The land-races may be useful for breeding programmes.
Bericht über eine Reise in die Sozialistische Libysche Arabische Volksjamahiriya 1983 zur Sammlung autochthoner Sippen von Kulturpflanzen
Zusammenfassung Die Reise erfolgte im Rahmen des Mediterranean Programme des IBPGR im April/Mai 1983 mit Teilnehmern aus der Sozialistischen Libyschen Arabischen Volksjamahiriya (Agricultural Research Centre, Tarbulus), des Istituto del Germoplasma, Bari, und des Zentralinstituts für Genetik und Kulturpflanzenforschung, Gatersleben. In Tripolitanien, dem Fezzan und dem Gebiet von Ghadmis wurden 316 Proben, meist von Getrieden und Gemüsen, gesammelt. In Tripolitanien und dem Gebiet von Ghadmis sind die Landsorten fast vollständig von neueren Sorten verdrängt worden. Im Fezzan schreitet die Generosion fort. Hier konnten noch zahlreiche Getreide- und Gemüselandsorten gesammelt werden. Die Landsorten können für Züchtungsprogramme nützlich sein.
1983 .
— 1983 . ( .-. ), . , 316 , . . , . .相似文献
57.
Soil development with time was investigated on beach ridges with ages ranging from about 1380 to 6240 14C-years BP at the eastern coast of central Patagonia. The main pedogenic processes are accumulation of organic matter and carbonate leaching and accumulation within the upper part of the soils. Soil formation is strongly influenced by incorporation of eolian sediments into the interstitial spaces between the gravel of which the beach ridges are composed. Different amounts of eolian material in the soils lead to differentiation into Leptosols (containing ≤ 10% fine earth in the upper 75 cm) and Regosols (containing > 10% fine earth). Soil depth functions and chronofunctions of organic carbon, calcium carbonate, pH, Ca:Zr, Mg:Zr, K:Zr, Na:Zr, Fe:Zr, Mn:Zr, and Si:Al (obtained from X-ray fluorescence analysis) were evaluated. To establish soil chronofunctions mean values of the horizon data of 0–10 cm below the desert pavement were used, which were weighted according to the horizon thicknesses. The depth function of pH shows a decrease towards the surface, indicating leaching of bases from the upper centimeters. Chronofunctions of pH show that within 6000 radiocarbon years of soil development pH drops from 7.0 to 6.6 in the Leptosols and from 8.1 to 7.5 in the Regosols. The higher pH of the Regosols is due to input of additional bases from the eolian sediments. Chronofunctions of Ca:Zr and K:Zr indicate progressive leaching of Ca and K in the Regosols, showing close relationships to time (R2 = 0.972 and 0.995). Na leaching as indicated by decreasing Na:Zr ratios shows a strong correlation to time only in the Leptosols (R2 = 0.999). Both, Leptosols and Regosols show close relationships to time for Fe:Zr (R2 = 0.817 and 0.824), Mn:Zr (R2 = 0.940 and 0.803), and Si:Al (0.971 and 0.977), indicating enrichment of Fe and Mn and leaching of Si. Leaching of mobile elements takes place on a higher level in the Regosols than in the Leptosols from the beginning of soil formation. Hence, a significant part of the eolian sediments must have been incorporated into the beach ridges very soon after their formation. 相似文献
58.
Rachel E. Creamer Pat Bellamy Helaina I. J. Black Clare M. Cameron Colin D. Campbell Paul Chamberlain Jim Harris Nisha Parekh Mark Pawlett Jan Poskitt Dote Stone Karl Ritz 《Biology and Fertility of Soils》2009,45(6):623-633
The use of indicators in soil monitoring schemes to detect changes in soil quality is receiving increased attention, particularly
the application of soil biological methods. However, to date, the ability to compare information from different laboratories
applying soil microbiological techniques in broad-scale monitoring has rarely been taken into account. This study aimed to
assess the consistency and repeatability of two techniques that are being evaluated for use as microbiological indicators
of soil quality: multi-enzyme activity assay and multiple substrate-induced respiration (MSIR). Data were tested for intrinsic
(within-assay plate) variation, inter-laboratory repeatability (geometric mean regression and correlation coefficient) and
land-use discrimination (principal components analysis). Intrinsic variation was large for both assays suggesting that high
replicate numbers are required. Inter-laboratory repeatability showed diverging patterns for the enzyme assay and MSIR. Discrimination
of soils was significant for both techniques with relatively consistent patterns; however, combined laboratory discrimination
analyses for each technique showed inconsistent correspondence between the laboratories. These issues could be addressed through
the adoption of reliable analytical standards for biological methods along with adequate replication. However, until the former
is addressed, dispersed analyses are not currently advisable for monitoring schemes. 相似文献
59.
Italy has been used as a country for estimating genetic erosion in crops. It was possible to compare early surveys (from the
1920s to the 1950s), especially on wheats, with results of later missions in the 1980s and 1990s. In the early years, a relatively
high genetic erosion was observed (13.2% p.a.). From the 1950s until the 1980s erosion rates between 0.48 and 4% p.a. were
estimated. In the little island of Favignana there was an erosion rate of 12.2% p.a. leading to the extinction of the last
wheat landraces of this island. There have been no significant differences in erosion rates between field- and garden-crops
though there has been the impression that garden crops are better preserved over the long run. Interestingly extinction rates
of wild plants (0.13% in the Mediterranean) come close to the average erosion rates of crop plants in the area.
1Dedicated to Erna Bennett on the occasion of her 80th birthday
2Lecture presented during the XVIIth Congress of EUCARPIA in Tulln, Austria, 2004 相似文献
60.