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2. Brandt iH026a plant growth regulator

Creator:
Nonomura, A. M., Pedersen, A., Brummel, D. P., Loveless, L., Lauria, A., Haschemeyer, B., and McBride, M. S.
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
zemědělství, regulátory růstu rostlin, dýchání, agriculture, plant growth regulators, respiration, glycoside, Govindjee, photosynthate, Z-scheme, 2, and 581
Language:
Multiple languages
Description:
iH026a is a formulation containing a biochemical class of plant growth regulator that modulates glycoconjugation through the plant lectin cycle. While lectins are common to vascular plants, we observed, consistent with reversible binding of sugars from lectins, enhancements of quantities and qualities of various features, including significant enrichment of Brix soluble sugars compared to controls in cherry, grape, and melon in trials conducted in Arizona and California, USA., A. M. Nonomura, A. Pedersen, D. P. Brummel, L. Loveless, A. Lauria, B. Haschemeyer, M. S. McBride, and Obsahuje bibliografické odkazy
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

3. Comparative photosynthesis, growth, productivity, and nutrient use efficiency among tall- and short-stemmed rain-fed cassava cultivars

Creator:
El-Sharkawy, M. A. and de Tafur, S. M.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
botanika, botany, agriculture, breeding, C3-C4, canopy, drought, ecophysiology, environment, gas exchange, leaf, Manihot, soils, tropics, and yield
Language:
Multiple languages
Description:
Field trials under rain-fed conditions at the International Center for Tropical Agriculture (CIAT) in Colombia were conducted to study the comparative leaf photosynthesis, growth, yield, and nutrient use efficiency in two groups of cassava cultivars representing tall (large leaf canopy and shoot biomass) and short (small leaf canopy and shoot biomass) plant types. Using the standard plant density (10,000 plants ha-1), tall cultivars produced higher shoot biomass, larger seasonal leaf area indices (LAIs) and greater final storage root yields than the short cultivars. At six months after planting, yields were similar in both plant types with the short ones tending to form and fill storage roots at a much earlier time in their growth stage. Root yield, shoot and total biomass in all cultivars were significantly correlated with seasonal average LAI. Short cultivars maintained lower than optimal LAI for yield. Seasonal PN, across cultivars, was 12% greater in short types, with maximum values obtained in Brazilian genotypes. This difference in PN was attributed to nonstomatal factors (i.e., anatomical/biochemical mesophyll characteristics). Compared with tall cultivars, short ones had 14 to 24 % greater nutrient use efficiency (NUE) in terms of storage root production. The lesser NUE in tall plants was attributed mainly to more total nutrient uptake than in short cultivars. It was concluded that short-stemmed cultivars are superior in producing dry matter in their storage roots per unit nutrient absorbed, making them advantageous for soil fertility conservation while their yields approach those in tall types. It was recommended that breeding programs should focus on selection for more efficient short- to medium-stemmed genotypes since resource-limited cassava farmers rarely apply agrochemicals nor recycle residual parts of the crop back to the soil. Such improved short types were expected to surpass tall types in yields when grown at higher than standard plant population densities (>10,000 plants ha-1) in order to maximize irradiance interception. Below a certain population density (<10,000 plants ha-1), tall cultivars should be planted. Findings were discussed in relation to cultivation and cropping systems strategies for water and nutrient conservation and use efficiencies under stressful environments as well as under predicted water deficits in the tropics caused by trends in global climate change. Cassava is expected to play a major role in food and biofuel production due to its high photosynthetic capacity and its ability to conserve water as compared to major cereal grain crops. The interdisciplinary/interinstitutions research reported here, including, an associated release of a drought-tolerant, short-stem cultivar that was eagerly accepted by cassava farmers, reflects well on the productivity of the CIAT international research in Cali, Colombia., and M. A. El-Sharkawy, S. M. de Tafur
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

4. Early Neolithic farming communities in Northern Europe: Reconsideration of the TRB culture

Creator:
Midgley, Magdalena S.
Type:
article and TEXT
Subject:
Mesolithic, Neolithic, Northern Europe, agriculture, flint industries, votive deposites, enclosures, burial, mezolit, neolit, severní Evropa, zemědělství, štípaná industrie, votivní depoty, ohrazení, and pohřby
Language:
Czech
Description:
The neolithisation of Northern Europe was neither synchronous nor uniform and it cannot be defined in simple terms. The early Neolithic populations of Northern Europe – known in the archaeological literature since the beginning of this century under the name of the TRB culture – are a consequence of a long period of contact and of mutual influences between communities with two contrasting life–styles: the Linearbandkeramik and its derivatives settled on the central European loess, and the immensely varied hunter– –gatherers roaming in the sandy and forested habitats of the North European Plain. The current significant issues, as seen through the prism of theoretical and methodological considerations, revolve around the models of transition most appropriate to circumstances in Northern Europe, the conceptual as well as real understanding of the complexity of late hunter-gatherers, the contribution of the Danubian tradition, and the dichotomy between regional diversity (a direct response to local conditions and specific requirements of individual human groups) and cultural unity (as demonstrated in the homogeneity of the process) which interlocked different cultural, economic and social phenomena into a web of dynamic relationships which lead to the emergence of such an extensive cultural complex in Northern Europe. and Neolitizace severní Evropy nebyla ani synchronní, ani jednotná, a nemůže být definována v jednoduchých termínech. Raně neolitické populace v severní Evropě – známé v archeologické literatuře od počátku tohoto století jako kultura nálevkovitých pohárů – jsou výsledkem dlouhodobých kontaktů a vzájemných vlivů mezi komunitami se dvěma odlišnými způsoby života: kulturou s lineární keramikou a jejími deriváty usídlenými ve střední Evropě a velice rozmanitými lovci–sběrači z písčitých a lesnatých severoevropských nížin. Významné otázky, viděno prizmatem teoretických a metodologických úvah, se soustřeďují kolem modelů přechodu, nejpřiměřenějšího podmínkám severní Evropy, pojmového, ale i reálného pochopení rozmanitosti pozdních lovců–sběračů, spolupůsobení dunajské tradice a dichotomie mezi regionální diverzitou (přímá odezva na lokální podmínky a specifické požadavky jednotlivých lidských skupin) a kulturní jednotou (demonstrovanou homogenitou procesu), která propojila různé kulturní, ekonomické a sociální fenomény do sítě dynamických vztahů, jež vedly k výskytu tohoto kulturního komplexu v severní Evropě.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/

5. Effect of slope position on soil properties and soil moisture regime of Stagnosol in the vineyard

Creator:
Magdić, Ivan, Safner, Toni, Rubinić, Vedran, Rutić, Filip, Husnjak, Stjepan, and Filipović, Vilim
Format:
počítač and online zdroj
Type:
model:article and TEXT
Subject:
hillslope, agriculture, Stagnosol, soil properties, soil water content, and Bg horizon
Language:
Slovak
Description:
Hillslope hydrology in agricultural landscapes is complex due to a variety of hydropedological processes and field management possibilities. The aim was to test if there are any differences in soil properties and water regime along the hillslope and to compare vineyard rows (vine) with inter-rows (grass) area for those properties. The study determined that there are significant differences in the contents of soil particle fractions, pH, and humus content along the slope (P < 0.0001), with lower confidence level in bulk density (P < 0.05). Differences between row and inter-row space were significant for the pH, humus, and silt content, but for sand and clay content, and bulk density differences were not determined. The study determined differences in soil water content among five slope positions (P < 0.0001), and between row and inter-row vineyard space (all with P < 0.05). Where in the upper slope positions (e. g., P1) soil water content was higher than on lower slope positions. Higher soil water content was observed at higher slope positions, associated with clay content. However, it can be concluded that the retention of moisture on the slope is more influenced by local-scale soil properties (primarily soil texture) and variability of the crop (row/inter-row) than the position on the slope.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

6. Environmental and land-use variables determining the abundance of Ambrosia artemisiifolia in arable fields in Hungary

Creator:
Pinke, Gyula, Karácsony, Péter, Czúcz, Bálint, and Botta-Dukát, Zoltán
Type:
article and TEXT
Subject:
agriculture, arable fields, decision trees, invasion, invasive plants, ragweed, weed distribution, and weed ecology
Language:
English
Description:
Ambrosia artemisiifolia is the most noxious invasive species of weed in Hungary. The aim of this study was to quantify the environmental and land-use factors that explain the variance in its abundance in arable fields. A survey of 243 arable fields was carried out across Hungary, and 19 environmental and 12 land-use factors were measured. These were used as explanatory variables in classification and regression tree models. The abundance of A. artemisiifolia was significantly higher at the edges than at the centres of fields. The most important land-use variables explaining the variance in abundance of A. artemisiifolia were crop type and crop cover, with the highest abundance recorded in sunflower fields and fields with low crop cover. The following explanatory environmental variables were associated with significantly higher A. artemisiifolia abundance: sandy or acidic soils, mean April precipitation > 39 mm, mean annual precipitation > 592 mm and mean May temperature < 15.5 °C. Ambrosia artemisiifolia was significantly less abundant in fields with soils containing high concentrations of Na, K and Mn. Both farmers and nature conservationists should be made aware of the conditions and practices that favour ragweed so that they can develop effective and selective ragweed control practices, particularly in arable habitats with a high diversity of weeds.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/

7. Global warming: causes and impacts on agroecosystems productivity and food security with emphasis on cassava comparative advantage in the tropics/subtropics

Creator:
El-Sharkawy, M. A.
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
fotosyntéza, zemědělství, klimatické změny, oxid uhličitý, zemědělské plodiny, lesy, skleníkové plyny, modelování a simulace, půda, teplota, globální oteplování, photosynthesis, agriculture, climate changes, carbon dioxide, agricultural crops, forests, greenhouse gases, modeling and simulation, soil, temperature, global warming, animal husbandry, cassava, tropics, subtropics, water stress, wild Manihot species, yield, 2, and 581
Language:
Multiple languages
Description:
Earth’s climate has experienced notable changes during the past 50-70 years when global surface temperature has risen by 0.8°C during the 20th century. This was a consequence of the rise in the concentration of biogenic gases (carbon dioxide, methane, nitrous oxide, chlorofluorocarbons, and ozone) in the atmosphere that contribute, along with water vapor, to the so-called ‘greenhouse effect’. Most of the emissions of greenhouse gases have been, and still are, the product of human activities, namely, the excessive use of fossil energy, deforestations in the humid tropics with associated poor land use-management, and wide-scale degradation of soils under crop cultivation and animal/pasture ecosystems. General Circulation Models predict that atmospheric CO2 concentration will probably reach 700 μmol(CO2) mol-1. This can result in rise of Earth’s temperature from 1.5 to over 5°C by the end of this century. This may instigate 0.60-1.0 m rise in sea level, with impacts on coastal lowlands across continents. Crop modeling predicts significant changes in agricultural ecosystems. The mid- and high-latitude regions might reap the benefits of warming and CO2 fertilization effects via increasing total production and yield of C3 plants coupled with greater water-use efficiencies. The tropical/subtropical regions will probably suffer the worst impacts of global climate changes. These impacts include wide-scale socioeconomic changes, such as degradation and losses of natural resources, low agricultural production, and lower crop yields, increased risks of hunger, and above all waves of human migration and dislocation. Due to inherent cassava tolerance to heat, water stress, and poor soils, this crop is highly adaptable to warming climate. Such a trait should enhance its role in food security in the tropics and subtropics., M. A. El-Sharkawy., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

8. Habitat preferences of a declining population of the little owl, Athene noctua in Central Poland

Creator:
Żmihorski, Michał, Romanowski, Jerzy, and Osojca, Grzegorz
Type:
article and TEXT
Subject:
grasslands, pastures, GIS, agriculture, farmland, and conservation
Language:
English
Description:
The number of little owls, Athene noctua is decreasing in many European countries. In order to evaluate causes of the decline in Poland, habitat preferences of this species were analysed. Using GIS methods, 25 settled territories of the little owl, recorded during field surveys between 2000 and 2005, were compared with 50 unsettled locations. It was found that the proportion of built-up areas was higher in the occupied territories than in the random locations. No differences in grassland, forest and field proportion, habitat diversity and edge length were recorded between the occupied, and the random locations. The amount of forest and the proportion of built up areas appeared to be the best predictor of the occurrence of the little owl. Next, habitat use at 7 additional territories, which were occupied by little owls in 1980–90s and later abandoned, was analysed. In 2006, as compared to the period 1980–90, numbers of pollard willows decreased, whereas the number of buildings increased in these territories. The overall results lead to a conclusion that the little owl shows a high degree of habitat plasticity. The decrease of the area of grasslands and numbers of pollard willows is not likely to explain the population decline of the species.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/

9. Klimatické změny ve středoevropském pravěku

Creator:
Bouzek, Jan
Type:
article and TEXT
Subject:
klimatické změny, pravěká populace, zemědělství, strategie využívání krajiny, climatic changes, prehistoric population, agriculture, and land use strategy
Language:
Czech and English
Description:
Studie shrnuje výsledky studia vztahů mezi klimatickými změnami a osídlením a využíváním krajiny v době poledové. Výzkum ukázal, že proměny klimatu se na pravěkém zemědělství a využívání krajiny odrážely zásadním způsobem a že ovlivnily vývoj pravěkých kultur. Optimalizovaný systém využívání krajiny, vytvořený jednou pravěkou kulturou, se stal při klimatických změnách fragilní. Reakcí na klimatické fluktuace, spočívající v nutnosti změny strategie využívání krajiny, byl někdy i zánik jedné archeologické kultury a její nahrazení kulturou novou. and The article summarizes the results of the study of relations between the prehistoric settlement pattern and climate during the Holocene. The pattern of relations between prehistoric settlement and landscape reflected climatic fluctuations. All prehistoric cultures had to find the optimal strategy of land use under given conditions, and the optimalized system of agriculture/animal husbandry became fragile; climatic changes caused usually the end of one prehistoric culture, while the next culture often reflected the necessary changes of economic strategy; establishment of a new system developed as a response to the new situation.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/

10. Komise pro dějiny a vývoj evropského zemědělství SIEF a česká etnografie v 60.-80. letech 20. století

Creator:
Woitsch, JIří
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
SIEF, Commission for History and Development of European Agriculture, Ethnologia Europaea, agriculture, and international project
Language:
Czech
Description:
The 1960s saw an extraordinary development of international cooperation within European ethnology. The reason were favourable international political circumstances, advanced research work of the progressive generation of ethnographers as well as institutional and paradigm establishment of the European comparative ethnology (Ethnologia Europaea), which was suggested mainly by Sigurd Erixon and his collaborators. Even the generation of exceptional personalities of Czechoslovak (or Czech and Slovak) ethnography participated in the work on large-scale projects; they also were members of supranational research teams and organizations. A plethora of internationally anchored research dealt with transport, grain cultivation and livestock rearing - i.e. themes relating to the agrarian ethnography, whereby it was the SIEF Commission or History and Development of European Agriculture that carried a lot of weight in the coordination of the above research in the late 1960s. The contribution analyses the background and work of the Commission, the results of international projects organised by it, and the influence of the large-scale research on the development and thematic targets of Czech ethnography in the 1960s through 1980s.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public