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131.
Nests of birds represent an unusual microhabitat for diverse groups of soil and epigeic invertebrates including millipedes. The millipede faunas of 301 birds nests from 63 localities throughout Slovakia were obtained by heat extraction of the nest substrates. In total 18 species of millipedes were found in 7 different types of nests of 40 bird species. The most frequent millipede species were Polyxenus lagurus and Proteroiulus fuscus. The similarities in the millipede nidifauna depending on the type of nests, ecological characteristics and geographical distribution of millipede species are discussed. 相似文献
132.
The simulation of phenological development in dynamic crop model: The Bayesian comparison of different methods 总被引:2,自引:0,他引:2
Andrej CeglarAuthor Vitae Zalika ?repinšekAuthor Vitae 《Agricultural and Forest Meteorology》2011,151(1):101-115
The main objective of our study was to use Bayesian methods to quantify the uncertainties related to phenological development of maize (Zea mays L.) under various climate conditions. For this purpose, five different phenological methods were implemented in the dynamic crop growth model, which was subsequently optimized, using the data acquired at three different locations in Slovenia. The sensitivity analysis of the crop model was performed in order to find the set of most influential physiological parameters. Subsequent Bayesian model comparison was used in order to quantify the impact of phenological method selection on the final maize yield. The results revealed the importance of using an appropriate phenological method in order to correctly estimate the duration of the growing season and yield, when used within dynamic crop model. The limitations of the phenological methods used in this study are discussed. The selection of phenological method itself did not have a significant influence on the yield estimation, except in years with high temperatures and limiting water conditions. This raises the concern that inaccurate simulation of phenological development may increase the uncertainties of impact assessment on crop yield where crop models are fed with future climate projections. 相似文献
133.
Oszvald M Balázs G Tömösközi S Békés F Tamás L 《Journal of agricultural and food chemistry》2011,59(17):9664-9672
The aim of this work was to compare the effects of incorporated wheat storage proteins on the functional properties of rice and wheat flours. The advantage of rice as a base flour compared to wheat is that it does not contain any wheat flour components and, therefore, has no interactive effect between wheat glutenin proteins. The incorporation of individual HMW glutenin subunit proteins (Bx6, Bx7, and By8) in different ratios had significant positive effects on the mixing requirements of both rice and wheat doughs. Reconstitution experiments using two x+y type HMW-GS pairs together with a bacterially expressed LMW-GS have been also carried out in this study. The largest effects of polymer formation and mixing properties of rice flour dough were observed when Bx and By subunits were used in a 1:1 ratio and HMW and LMW glutenin subunits in a 1:3 ratio. However, using the same subunit ratios in wheat as the base flour, these synergistic effects were not observed. 相似文献
134.
Biswanath Dari Debjani Sihi Santanu Kumar Bal Sanju Kunwar 《Paddy and Water Environment》2017,15(2):395-401
Rice (Oryza sativa L.) is the most important staple food crop in the southern region of Asia, and Indian subcontinent being one of the major producers. Production of conventional transplanted rice requires a large amount of irrigation water, labor, and energy. The scarcity of irrigation water has encouraged farmers to adopt an alternative rice production system, i.e. the direct-seeded rice (DSR), which is proposed to be farmers’ friendly with a potential to save water. Our study reports the performance of DSR with respect to yield and water expense efficiency based on different irrigation regimes and dates of sowing. A field experiment was conducted in the semi-arid region of northern India during the rainy season of 2011 with two treatment combinations (dates of sowing: 15th May and 5th June and three irrigation regimes: irrigation scheduled at irrigation water-to-cumulative potential evapotranspiration; IW/CPE ratio of 1.0, 1.5 and 2.0) in a completely randomized design. We found statistically higher water expense efficiency of DSR sown on 5th June as compared to DSR sown on 15th May without any significant differences in growth and yield. A significant yield difference between DSR grown with irrigation regimes of IW/CPE 1.0 and 1.5 and DSR grown with irrigation regimes of IW/CPE ratio 2.0 were observed. The DSR grown with irrigation regimes of IW/CPE ratio of 1.5 resulted in significantly higher water expense efficiency than the one with IW/CPE ratio of 2.0. Obtaining a higher yield of DSR under scarce irrigation water might be a trade-off between optimum water use and maximum yield avoiding excess ground water exploitation in sub-tropical semi-arid regions of India. Our study suggests that sowing time and irrigation regimes are two important aspects of “rice production” to attain “win–win” solution. Thus, strategic and judicial use of irrigation water with management of sowing time could potentially escalate the rice production in water scarce regions of India. 相似文献
135.
Utilization from bio fertilization is well known a considerable tool to improve the yield and fruit quality of various crop fruits through the increasing emphasis on maintain of soil health, minimize environmental pollution and decrease the use of chemical fertilization. In this study, in order to improve wine grape quality features of cv. Shiraz, four different doses of foliar microbial fertilizer, including 0, 1000, 2000 and 3000?ppm were applied at two different terms as Term I (mostly; pre-bloom applications) and Term II (mostly; post-bloom applications). However, there were no influences of application terms of foliar microbial fertilizer treatments; treatment doses had considerable effects on yield and quality parameters. The lowest p-values, meaning the highest berry quality, from doses of foliar microbial fertilizer were obtained from 2000?ppm (105.08?μW), 1000?ppm (110.40?μW), 3000?ppm (112.97?μW) and 0?ppm (119.58?μW). Comparing the applications of foliar microbial fertilizer, it was observed that doses of 2000?ppm (3155.56?mg/kg), 1000?ppm (3000.92?mg/kg) and 3000?ppm (2530.19?mg/kg) exhibited higher total phenolic compounds content when compared with 0?ppm treatment (2206.97?mg/kg). Berries from grapevines applied with the doses of 2000, 1000 and 3000?ppm foliar microbial fertilizer respectively shown higher total anthocyanin content such as 1230.19, 1160.85 and 865.86?mg/kg compared to 0?ppm (637.37?mg/kg). As a result, research the findings indicated that 2000 and 1000?ppm doses of foliar microbial fertilizer were obviously effective on wine grape quality features of cv. Shiraz in terms of electrochemical property, total phenolic compounds content and total anthocyanin content. 相似文献
136.
137.
Y. Bal G. Kelling S. Kapur E. Aka H. etin O. Erol 《Land Degradation \u0026amp; Development》2003,14(4):363-376
Two well‐known ancient sites in southern Anatolia were selected to investigate and quantify the impact of historical land degradation on the Mediterranean coast of Turkey. These sites are the Luwian settlements of Kelenderis (modern Aydıncık) and nearby Nagidos (Bozyazı), both in Mersin Province and both occupied since around 4000 BP . Changes in local climatic conditions over this period have produced variations in the rates of fluvial transport of sediment/soil from the hinterland into the relevant deltaic regions, thus influencing rates of coastal progradation and aggradation. In addition, both eustatic and neotectonic movements have contributed to deltaic subsidence and/or hinterland uplift, with consequential impact on coastal evolution (positive or negative). The novel geoarchaeological methodology adopted in this study involves the creation of a graphical archive from detailed and standardised measurements taken from rectified mono‐ and stereoscopic aerial photographs. These archival data were then integrated with data from several types of historical map and field measurements in order to develop a geographical information system (GIS) database that could be interrogated, enabling graphical models of past coastal change to be constructed and calculations then made of the coastal configurations at successive historical periods. These calculations reveal that over the past 6000 years there has been only limited erosion/degradation in the karstic hinterland supplying the sediment to these two study sites (contrary to some previous statements concerning the high degradation risk of Mediterranean karst terrains). Furthermore, rates of progradation in each delta appear to have become diminished or even reversed in the past several decades as a result of both natural and anthropogenic factors. The precise contribution of neotectonic movements in this seismically active zone remains unquantified and is a topic requiring further interdisciplinary study. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
138.
139.
Balß-Hannover 《European Journal of Forest Research》1916,38(5):268-273
140.
Relationships between climatic factors and C, N pools in particle-size fractions of steppe soils, Russia Many soils of the Russian steppe are characterized by high soil organic matter contents and similar parent material. Thus, they are suitable for investigations of a climatic impact on C and N pools. We sampled 10 topsoils of the zonal Russian steppe at 0–10 and about 50–60 cm depth intervals. After particle-size fractionation into clay (<2 μm), silt (2–20 μm), fine sand (20–250 μm) organic C and N concentrations were determined in bulk soils and fractions. The results suggest that especially the older organic matter of the subsoil (in the silt fraction) is correlated with climatic factors. Topsoils show less evidence for climatic influences on C and N pools. As the ratio of mean annual precipitation to potential evaporation (=N/V) increases, C/N ratios decrease in all fractions and, thus, in the bulk subsoil. Obviously the degree of soil organic matter alteration was more pronounced in the order Greyzem (N/V = 1.0) > Chernozem, Phaeozem (N/V = 0.89) > Haplic Kastanozem (N/V = 0.6) > Calcic (N/V = 0.34), and Gypsic Kastanozem (N/V = 0.32). The organic carbon contents of the bulk subsoil are highest in the subsoil of the Chernozem and Phaeozem, and decrease with increasing N/V ratio (i.e., increasing heat input and dryness) to the Calcic Kastanozem. This is accompanied by an increasing enrichment of organic carbon in the silt fractions (r = ?0.99 for the correlation of the C enrichment in silt with N/V). 相似文献