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1.
We propose that from approximately 3 to 1 million years ago, ice volume changes occurred in both the Northern and Southern Hemispheres, each controlled by local summer insolation. Because Earth's orbital precession is out of phase between hemispheres, 23,000-year changes in ice volume in each hemisphere cancel out in globally integrated proxies such as ocean delta18O or sea level, leaving the in-phase obliquity (41,000 years) component of insolation to dominate those records. Only a modest ice mass change in Antarctica is required to effectively cancel out a much larger northern ice volume signal. At the mid-Pleistocene transition, we propose that marine-based ice sheet margins replaced terrestrial ice margins around the perimeter of East Antarctica, resulting in a shift to in-phase behavior of northern and southern ice sheets as well as the strengthening of 23,000-year cyclicity in the marine delta18O record. 相似文献
2.
Hakan Basak K. Mesut Çimrin Metin Turan Ekrem Ozlu 《Communications in Soil Science and Plant Analysis》2019,50(3):350-361
Mycorrhiza has attracted interest as one of the microorganisms that increase a crop’s salt stress tolerance. This study was conducted to determine the impacts of mycorrhiza inoculation and applying salt at different ratios on the yield of peppers and amino acid concentrations. The study was conducted in greenhouse conditions on loamy soils with four salt treatments, two mycorrhiza inoculations and a control in a complete randomized block design. The present study indicated that salt treatment alone was significantly correlated with crop stem and root amino acid concentrations, RWC% and leaf sizes, whereas applying mycorrhiza showed a positive relationship to stem height, stem and root wet weight, and root amino acids but led to a decloine in root serine and glutamine, and stem amino acid and glutamine. In conclusion, inoculating with mycorrhiza was observed to make a positive contribution to salt stress tolerance at different levels in almost all the parameters examined. 相似文献
3.
Zinnur Gozubuyuk Mesut Cemal Adiguzel Erdal Dasci 《Archives of Agronomy and Soil Science》2020,66(12):1611-1626
ABSTRACT Energy requirement increases rapidly in agriculture due to the increase in mechanization. The aim of the present study is to evaluate the energy use efficiency of silage maize under three different tillage practices (conventional, reduced, no-tillage) combined with four different irrigation levels (full and three deficit irrigations). The no-tillage and reduced tillage practices provided savings in input energy at the rate of 17.4 and 9.1%, respectively compared to the conventional tillage. The highest silage yields in all irrigation levels were obtained in the no-tillage practice. Therefore, in full and deficit irrigated silage maize, the highest energy ratio, energy productivity and net energy and the lowest specific energy values were manifested in the no-tillage practice. Energy rates in the no-tillage practice were higher by 34.2 and 22.9% than the conventional and the reduced tillage practices, respectively. Moreover, the direct and non-renewable energy requirements were the lowest in the no-tillage practice. In conclusion, the fully-irrigated no-tillage practice can be recommended to obtain the highest energy use ratio and productivity. However, no-tillage irrigated with up to 50% less water amount could be a better alternative for areas with a water shortage by improving the energy use ratio with better water and fuel savings. 相似文献
4.
Ram C. Sharma Alexei I. Morgounov Hans J. Braun Beyhan Akin Mesut Keser David Bedoshvili Ahmet Bagci Christopher Martius Maarten van Ginkel 《Euphytica》2010,171(1):53-64
Improved winter wheat (Triticum aestivum L.) cultivars are needed for the diverse environments in Central and West Asia to improve rural livelihoods. This study was
conducted to determine the performance of elite winter wheat breeding lines developed by the International Winter Wheat Improvement
Program (IWWIP), to analyze their stability across diverse environments, and to identify superior genotypes that could be
valuable for winter wheat improvement or varietal release. One hundred and one advanced winter wheat breeding lines and four
check cultivars were tested over a 5-year period (2004–2008). Grain yield and agronomic traits were analyzed. Stability and
genotypic superiority for grain yield were determined using genotype and genotype × environment (GGE) biplot analysis. The
experimental genotypes showed high levels of grain yield in each year, with mean values ranging from 3.9 to 6.7 t ha−1. A set of 25 experimental genotypes was identified. These were either equal or superior to the best check based on their
high mean yield and stability across environments as assessed by the GGE biplot analysis. The more stable high yielding genotypes
were ID800994.W/Falke, Agri/Nac//Attila, ID800994W/Vee//F900K/3/Pony/Opata, AU//YT542/N10B/3/II8260/4/JI/Hys/5/Yunnat Esskiy/6/KS82W409/Spn
and F130-L-1-12/MV12. The superior genotypes also had acceptable maturity, plant height and 1,000-kernel weight. Among the
superior lines, Agri/Nac//Attila and Shark/F4105W2.1 have already been proposed for release in Kyrgyzstan and Georgia, respectively.
The findings provide information on wide adaptation of the internationally important winter wheat genotypes, and demonstrate
that the IWWIP program is enriching the germplasm base in the region with superior winter wheat genotypes to the benefit of
national and international winter wheat improvement programs. 相似文献
5.
Sung Il Lee Kerim Y. Aydin Paul D. Spencer Thomas K. Wilderbuer Chang Ik Zhang 《Fisheries Science》2010,76(3):411-434
We evaluated the role of flatfishes in the organization and structure of the eastern Bering Sea ecosystem using the Ecopath/Ecosim
approach. As basic input data for the Ecopath/Ecosim model, we used estimates of biomass from bottom trawl surveys and age-structured
population models, production/biomass (P/B) ratio, consumption/biomass (Q/B) ratio, diet composition (DC), and fisheries harvests for each component of species or species groups. We estimated the trophic
level of each component, niche overlaps among flatfishes, and the impacts of competition and predation on flatfish species
in the eastern Bering Sea ecosystem. Based on those estimates, we developed the tropho-dynamic structure of the ecosystem,
and the model was used to simulate ecological effects of fishery exploitation patterns. No single flatfish species appeared
to have a profound and uniquely important role in the organization and structure of the ecosystem. Instead, the most important
component among the guild of flatfish species appeared to be yellowfin sole Pleuronectes asper, which had greater biomass than other flatfish and a relatively diverse diet among the small flatfish species. Pacific halibut
Hippoglossus stenolepis, Greenland turbot Reinhardtius hippoglossoides, and arrowtooth flounder Atheresthes stomias were important keystone predators in the eastern Bering Sea ecosystem together with some groups of marine mammals and sea
birds. Intra flatfish complex cannibalism was not observed, however, substantial diet overlaps were common in the flatfish
guild system. 相似文献
6.
Kirstin K. Holsman Kerim Aydin Jane Sullivan Tom Hurst Gordon H. Kruse 《Fisheries Oceanography》2019,28(3):345-358
Pacific halibut (Hippoglossus stenolepis) are an ecologically, commercially, and culturally important Alaskan groundfish species. Commercial harvest of halibut dates back to the late 19th century and has been managed by the International Pacific Halibut Commission (IPHC) since 1921. IPHC surveys have revealed declining trends in survey biomass in multiple regions and region‐specific declines in mean size‐at‐age (size‐at‐age) over the past two decades (>50% in some areas). Changes in size‐at‐age can arise from a variety of physical, ecological, sampling, and fishery effects, including size‐dependent fishery or predation mortality, alteration in growth from variability in prey quality or quantity, and changes in temperature‐dependent metabolic demands. Here, we develop and apply a bioenergetics model for halibut using survey‐based diet and temperature data for Alaska to evaluate potential environmental drivers of size‐at‐age. In general, juvenile (<40 cm fork length) foraging rates were highest in the Gulf of Alaska concomitant with higher potential growth and elevated basal metabolic demands during warm summer conditions. In contrast, adult (40–120 cm FL) potential growth was highest in the Eastern Bering Sea, potentially reflecting lower metabolic costs and higher rates of prey consumption in that region. We additionally find evidence for interannual variation in potential growth, with a higher frequency of reduced growth potential in the last decade, particularly in the Eastern Bering Sea in 2015 and 2016 for both juvenile and adult halibut. These results suggest the potential for patterns in size‐at‐age to arise from trophic and environmental constraints that collectively limit growth in some regions and years. 相似文献
7.
Adem Gunes Metin Turan Nurgul Kitir M. Sefik Tufenkci Kerim Mesut Cimrin Ertan Yildirim Sezai Ercisli 《Erwerbs-Obstbau》2016,58(3):177-184
Deficiency of Boron (B) is widespread in the many parts of region of Turkey. So, the effects of boron and plant growth promoting bacteria (Bio-B) on the fruit yield, antioxidant enzyme activity and plant freeze injury of strawberry cv. Fern were investigated under field conditions between 2013 and 2014. The experimental plot was a completely randomized design with 4 replicates. Control and Bio-B were used as fertilizer agent in the experiment. Bio-B fertilizer was applied in three methods as soil, foliar and soil + foliar application methods to strawberry plants. Data through 2 years showed that the use of Bio-B significantly increased fruit yield, antioxidant enzyme activity and decreased freeze injury of strawberry leaf. Soil + foliar applications of Bio-B fertilizer increased to fruit yield compared to the control by 55.91?%. However, foliar application of Bio-B fertilizer increased to catalase (CAT), peroxidase (POD), and superoxide dismutase (SOD) enzyme activity compared with the control treatment 41.86?%, 48.99?%, and 26.59?%, respectively and decreased freeze injury of strawberry leaves 27.41?%. Overall, the results of this study suggest that Bio-B fertilizer application have the potential to increase the yield, antioxidant enzyme activity and decreased freeze injury of strawberry plants under field conditions. 相似文献
8.
Alper YILMAZ Bulent EKIZ Mustafa OZCAN Cuneyt KAPTAN Hulya HANOGLU Mesut YILDIRIR 《Animal Science Journal》2009,80(4):460-467
The aim of study was to investigate the effect of genotype on carcass measurements and meat quality characteristics of purebred Hair Goat, Saanen × Hair Goat (F1 and B1 ) kids under an intensive production system. In total, 24 kids were slaughtered at the age of approximately 133 days. Kids were fattened for 56 days immediately after weaning. Hot carcass weights were 6.78, 7.61 and 7.02 kg and dressing percentages were 49.71, 49.27 and 48.78%, respectively ( P > 0.05). Differences between genotypes for carcass measurements and indexes were not significant. Effect of genotype on pH measurements, drip loss, water holding capacity, cooking loss and Warner Bratzler shear force values were not significant. Meat lightness values at 0 h, 1 h and 1 day after cutting were higher in crossbred kids than Hair Goat kids ( P < 0.05). Redness value was significantly higher in meat samples of Hair goat kids at 0 h, 1 h and 1 day measurements ( P < 0.05). Kid genotype had no significant effect on meat sensory characteristics, except tenderness. Panelists gave lower scores for meat tenderness to F1 and B1 crosses compared to purebred Hair Goat kids. In conclusion, higher meat lightness values of crossbred kids, at particularly B1 level, might have a positive effect on the consumer choices. 相似文献
9.
The present study investigated the antifungal effects of essential oils of oregano (Origanum onites) and laurel (Laurus nobilis) on Saprolegniasis, a disease that occurs in rainbow trout eggs during the incubation period. Oregano and laurel were ground after drying, and essential oils were obtained by water distillation method using a Clevenger apparatus. The essential oils were added to potato dextrose agar (PDA) at the rates of 1–1000 ppm, and the minimum inhibitory concentration (MIC) was determined as 250 ppm whereas the minimum lethal concentration (MLC) was determined to be 500 ppm for both plants. In the in vivo trials, fertilized eggs were treated with predetermined doses either by bathing during water hardening and incubation period or only during incubation period, and death rates were monitored during embryological development. The best larvae hatching rate was determined in 500 ppm oregano and 500 ppm laurel groups treated during water hardening plus daily as 82.11% and 79.87%, respectively. According to the results, it was determined that oregano and laurel essential oils exhibited better results in all doses compared with the negative control group, and 500 ppm dose had a better effect than the positive control group treated with formalin. 相似文献
10.
Galip Yuce Didem Ugurluoglu Alime T. Dilaver Turgay Eser Mesut Sayin Mert Donmez Sakir Ozcelik Funda Aydin 《Water, air, and soil pollution》2009,202(1-4):69-89
The high radioactivity and trace elements in drinking water are common concerns for human health. The aim of this study was to investigate the eligibility of groundwater for drinking purpose in terms of both radioactivity and trace element contents in Eskisehir Region (Turkey). The study area is located in a highly populated residential area where water supply is mostly met from groundwater. The area is about 20,000 km2, where igneous, metamorphic, and sedimentary rocks are exposed. The 209 water samples collected from 84 water resources (including thermal waters) were analyzed with respect to major ions, trace elements, and radioactivity (gross alpha and gross beta) during both in wet and dry seasons. Based on the analysis results, trace elements in 49 samples of 84 water resources were over the limits of Code TS 266 1997 (Turkish Drinking Water Standards) and WHO 1993 standards. Particularly, Fe, Mn, Al, As, Ba, Zn, Cr, Cu, and B ion concentrations exceeded the limits. The gross alpha values in 18 locations and gross beta values in three locations also exceeded the limits of aforementioned standards in terms of radioactivity (gross alpha?=?0.1 Bq L?1; gross beta?=?1 Bq L?1). Furthermore, water radioactivity levels were close to the allowable limits in 33 water resources. The obtained results explicitly indicate that there is a strong relationship between the higher radioactivity–trace element contents and geochemical composition of rocks, which controls the radioactivity and trace element concentrations present in the aquifer. 相似文献