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Juraj Lieskovský Pavol Kenderessy Jana Špulerová Tibor Lieskovský Peter Koleda Felix Kienast Urs Gimmi 《Landscape Ecology》2014,29(5):867-877
Collectivization of agriculture (1950s–1970s) was one of the most important periods in landscape development in Slovakia. Traditionally managed agricultural landscapes, that covered more than half of the Slovak territory, were transformed into large-scale fields and only fragments of traditional agricultural landscapes survived. We mapped the remaining traditional agricultural landscapes using aerial photos and historical maps. We then statistically analyzed the various geographical factors and their influence on the transformation process of traditional and collectivized fields, i.e., slope steepness, soil fertility, distance from settlements and isolation from regional capital cities. The comparison was performed using classification tree analysis. We constructed a set of decision rules that explain why fields were managed traditionally or collectivized. Our findings show that traditional agricultural fields were more likely to persist on steep terrain, less fertile soils, and on locations that were closer to the settlements, but more isolated from the regional capital cities. Steepness played the most important role: small-scale fields located on steep areas were not accessible to heavy machinery and therefore, frequently survived the collectivization. We show that the selected geographical factors are good explanatory variables for the collectivization of arable fields and orchards. For vineyards and grasslands, however, the explanatory power of the selected geographical factors is lower, and we suspect that other factors, not depicted in the analysis play an important role. 相似文献
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Jozef Kov��?ik Bo?ivoj Klejdus Josef Hedbavny Pavol M��rtonfi Franti?ek ?tork Lenka M��rtonfiov�� 《Water, air, and soil pollution》2011,218(1-4):681-691
Selected physiological parameters and copper uptake by three chamomile (Matricaria chamomilla) cultivars (two tetraploid????Lutea?? and ??Unknown?? and one diploid????Novbona??) exposed to 60 ??M Cu over 7 days were studied. Genome size was 10.6 and 5.5 pg DNA/2C and chromosome number 2n?=?36 and 2n?=?18 in tetraploids and diploid, respectively. Root tissue water content and dry biomass were more reduced in diploid cultivar. Soluble proteins were depressed by Cu excess in all cultivars without respect to ploidy. Lignin accumulation and cinnamylalcohol dehydrogenase activity was the highest in Novbona. Phenylalanine ammonia-lyase activity was stimulated in tetraploid but reduced in diploid roots. Diploid contained higher amount of Cu and soluble phenols in both shoots and roots. Sulphur-containing amino acids were stimulated in Cu-exposed shoots independently on ploidy level. Potassium content was more reduced in the diploid cultivar. Our data indicate that induction of phenolic metabolism is faster in diploid cultivar which also contained higher amount of Cu. In this view, polyploidisation is a good tool for the reduction of shoot metal accumulation and growth tolerance to Cu excess. Identity of Czech tetraploid cultivar ??Unknown?? is also discussed. 相似文献
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Edita Bagdonait? Pavol MártonfiMiroslav Rep?ák Juozas Labokas 《Industrial Crops and Products》2012,35(1):302-308
The growing demand for the medicinal plant, Hypericum perforatum, is not being met by available supply in many countries. The conditions for obtaining quality crude drug should be thoroughly studied to ensure adequate supply. The current study describes the variation of major bioactive compounds in different accessions of H. perforatum (Hypericaceae) in two floral development stages. Two extraction procedures were evaluated for the quantification of the major bioactive compounds in H. perforatum. The Soxhlet extraction technique was demonstrated to be more effective with higher extraction yields. The contents of rutin, hyperoside, quercitrin, quercetin, and 3,8″-biapigenin were determined by high performance liquid chromatography (HPLC). This procedure was used to establish the variation in the contents of flavonoids in the field-growing H. perforatum and to evaluate factors predetermining that variation with some practical implications for utilization. A significant difference in flavonoid contents between two floral development stages was detected. The results of the study showed that rutin prevailed during the budding stage, whereas quercitrin, quercetin, and 3,8″-biapigenin were dominant during the full-flowering stage. The contents of hyperoside were similar in both developmental stages of the plants. The highest amounts of the most bioactive compounds were observed in the full-flowering stage, which could therefore be considered the best stage for the harvesting of the raw material of H. perforatum, known as Hyperici herba in pharmaceutics. The study revealed evident intraspecific variations in the flavonoid contents of H. perforatum. Several chemotypes were recognized by qualitative and quantitative differences in flavonoids. Qualitative analysis of the flavonoid contents confirmed the presence of the chemotype of H. perforatum containing no rutin, though the chemotype with higher levels of both rutin and hyperoside was more frequent. The accessions of H. perforatum also showed remarkable differences in chemical composition depending on the origin of plants. Therefore, employing the correct developmental stage for the harvesting of the selected accessions of H. perforatum is highly recommended for the quality production of the drug Hyperici herba. 相似文献
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为丰富我国冬小麦遗传多样性,为其遗传改良提供物质保障,对引进的104份斯洛伐克冬小麦种质资源的株高、株穗数、穗长、小穗数、穗粒数和千粒质量等主要农艺性状进行了调查分析。研究结果表明:引进的资源主要表现为株高偏高、穗子较大、千粒质量偏低的特点,且株高、穗长与千粒质量三性状均与对照品种存在极显著差异;6个性状变异系数幅度为0.08~0.37,变异系数的顺序为株穗数>株高=主茎穗粒数>千粒质量>穗长>小穗数,表现了丰富的遗传多样性;64份冬性种质与40份春性种质的千粒质量差异达到极显著水平,株高和主茎穗粒数差异达到0.05显著水平,株穗数、穗长和小穗数差异不显著;株高与株穗数、株高与穗长、穗长与小穗数、穗长与穗粒数、小穗数与穗粒数呈极显著正相关,穗长与千粒质量、穗粒数与千粒质量呈显著正相关;聚类分析将104份种质分为4类;筛选出综合农艺性状优良的种质3份,可直接作为亲本材料应用于黄淮冬麦区的小麦遗传改良研究。 相似文献
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通过化学杀雄配制出杂交种衡杂102,表现出较好的高产性、节水性及适应性。水处理单位面积穗数、穗粒数超标优势为5.77%和3.97%,均达0.05显著水平;千粒重、产量超标优势为9.36%和12.21%,达0.01极显著水平。节水处理平均产量482.44 kg/667 m2,比对照增产8.29%,名列30个参试品种第1名。通过杂种优势利用,可以选育出高产、节水的小麦杂交种。 相似文献
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The fate of cadmium in field soils of the Danubian lowland 总被引:1,自引:0,他引:1
Lubomir Lichner Pavel Dlapa Miloslav Sir Andrea Cipakova Beata Houskova Pavol Fasko Viliam Nagy 《Soil & Tillage Research》2006,85(1-2):154-165
The susceptibility of soils to deep penetration of cadmium was assessed by measuring cadmium adsorption on soil particles <0.01 mm, easily mobile in soil macropores, and bypassing ratio. The latter is defined as a ratio of the rate of macropore flow to the rate of total (macropore and matrix) flow. Measurements were made on soils from the Danubian lowland, which is a large (1260 km2) agriculturally managed area situated in the south-west of Slovakia, with a shallow (0.5–3.8 m deep) underlying aquifer containing about 10 km3 of freshwater. In this study, the susceptibility of soils to deep penetration of cadmium was assessed on light, loamy-sand soil in Kalinkovo, medium heavy, loamy soil in Macov, and heavy, clay soil in Jurova. It was found that when the interaction between soil and cadmium lasted 1 min, more than 35, 32, and 48% of cadmium was adsorbed on the particles <0.01 mm in soils from Kalinkovo, Macov, and Jurova, respectively. In the case of ponding infiltration, more than 50% of water can flow via topsoil macropores in Kalinkovo, about 70% in Macov, and 96% in Jurova. This value of bypassing ratio can be met during an irrigation/rain with higher intensity then the infiltration rate into the soil matrix of studied soils. As the rains resulting in the macropore flow can occur 24 times on average in south-western Slovakia during the vegetation season, the probability of deep penetration of cadmium is very high, mainly during an initial stage of rainfall. For this reason, some mitigative agricultural practices (e.g. subsurface fertilizer banding or shallow ploughing) should be used in this region to prevent soils from the deep penetration of cadmium. 相似文献
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乔文臣 赵明辉 李会敏 孙书娈 孟祥海 魏建伟 李丁 李强 赵凤梧 Pavol Hauptvogel Edita Gregov Daniela Benedikova 《中国农学通报》2017,33(2):1-6
为了明确冬小麦新品种‘衡6632’的高产高效栽培技术措施,为该品种大面积应用提供理论依据,进行了不同播期和种植密度对该品种产量及其构成因素影响的研究。试验采用裂区设计,设5个播期和6个种植密度处理,于2014—2015年在河北省深州市护驾迟镇旱作节水试验站进行试验。结果表明:(1)播期对单位面积穗数、千粒重及产量有显著影响,但对穗粒数影响不显著;种植密度对产量及其构成因素均有显著影响。(2)产量随着播期的推迟和种植密度增加呈现先升高后降低的趋势。在一定范围内,‘衡6632’单位面积穗数随着播期的推迟而减少,随密度的增加而增加;穗粒数、千粒重随播期的推迟而增加。穗粒数在种植密度300万/hm~2以上时随种植密度增加而减少。千粒重随种植密度的增加而降低。研究分析表明:‘衡6632’在春一水条件下,适宜播期为10月7—19日,最佳播期为10月10—15日,相应的种植密度为225万~300万/hm~2。 相似文献
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通过对普通小麦(T.aestivum)、四倍体硬粒小麦(T.durum)种问杂交超高产新种质HsZ6.06.56性状表现分析表明:该种质与受体亲本石4185相比,挑旗期、抽穗期及成熟期分别提早1,1及2d,株高、穗长、小穗数三性状等同于受体。在产量构成三因素中,株穗数、穗粒数等同于受体,方差分析差异不显著;千粒重是构成该种质超高产的主要因素,本试验中单项指标超受体幅度达27.72%。利用种间杂种优势,是创造小麦超高产新种质的有效途径。 相似文献
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Background, Aims and Scope Being an integral part of nature, soil affects all main natural resources and is simultaneously affected by them. This is
due to soil management practices (agriculture, forestry) and to the leaching and emission of soil substances. Soil affects
mainly water resources and the open air. In this work, soil nitrate production as a possible cause for nitrate leaching and
nitrogen emission from soil into the air was determined and generalized. CO2 emissions from soil into the air were quantified as well. All data were generalized and evaluated.
Methods The data were obtained by analyzing samples taken from nine different soils in Slovakia during 3 years.
Results and Discussion Between 30 and 50 kg of nitrate nitrogen were produced in non-N-fertilized soils during the growing season. Application of
fertilizer N yielded 50 to 90 kg N-NO3-. About 111 thousand tons of N-NO3 are produced yearly in all non-N-fertilized agricultural soils in Slovakia. On the average, about 10,061 thousand tons of
C-CO2 can be produced in the soil cover during the growing season (about 4.2 tons of C-CO2 per ha).
Recommendation and Outlook Published data suggest that it is necessary to decrease soil nitrate production and to reduce CO2 emissions from soils. The data also attest to a very high level of external effects of soil, including negative effects accelerated
mainly by human activities. 相似文献