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141.
Sod establishment and turfgrass growth as affected by urea–formaldehyde resin foam soil amendment 总被引:1,自引:0,他引:1
Panayiotis A. Nektarios Aimilia-Eleni Nikolopoulou Ioannis Chronopoulos 《Scientia Horticulturae》2004,100(1-4):203-213
Urea–formaldehyde resin foam (UFRF) has recently been introduced as a soil amendment for turfgrass culture. A field study was performed to evaluate the impact of UFRF on soil physical and chemical properties, sod establishment and turfgrass shoot and root growth. Treatments included a non-amended, sandy loam soil and the same soil amended with UFRF at a rate of 20% (v/v) incorporated into the upper 0.1 m of the substrate. Physical and chemical analyses of the two substrates involved the determination of bulk density, total porosity, air-filled porosity at 0.4 m, moisture release curve, pH and electrical conductivity. Turfgrass growth was determined through several measurements that included shoot growth rate, root growth rate and monitoring of three root architecture parameters namely, total root length, total root area and mean root diameter. Turfgrass establishment was evaluated by measuring the vertical force applied to detach the sod from the substrate.UFRF amendment did not influence pH and EC and provided minimal alterations (non-significant) in soil physical properties by slightly increasing total porosity, easily available water and air-filled porosity, and by reducing bulk density. The impact of UFRF amendment improved cumulative clipping yield in five sampling dates but root growth and sod establishment rate were better than the control only on one sampling date. There appears to be limited benefit in amending soil with UFRF. 相似文献
142.
马艳凤 《国外畜牧学(猪与禽)》2006,(4):12-13
乳酪加工为我们提供了一种很有潜在价值的乳制品,可用以添加入断奶仔猪的饲料之中,但在决定选用何种来源的乳清粉之前应慎重考虑以下各点。 相似文献
143.
Sweet sorghum (Sorghum bicolor (L.) Moench) was introduced recently into Greece and is being cultivated experimentally for the production of liquid biofuel.
A pilot survey was conducted in October 2005 to provide information on the species composition and density of its lepidopterous
stem borers, which appear to cause severe losses in production. The dominant pest in that season wasSesamia nonagrioides Lefebvre, with a mean density of 1.41 larvae per plant. Larvae were sampled from various plant internodes and found to have
a preference for the lower ones. Analysis of variance showed no significant effects on larval density of the irrigation levels
or of the organic — conventional soil fertilization method. A significant negative correlation was found between the body
length ofS. nonagrioides larvae and the internode from which they were retrieved. This is the first published report of sorghum borer pests in Greece.
http://www.phytoparasitica.org posting Feb. 7, 2007. 相似文献
144.
The germination of bay laurel (Laurus nobilis L.) seeds wasexamined both in the laboratory and in the field during twoyears. Seeds were collected from a grove in a garden in the townof Drama, Northern Greece, by mid November in the first year andby late November in the second year. The seeds with and withoutpericarp were given a warm-moist (20 °C day/12 °C night) oncold-moist (4±1 °C) treatment in peat or sand. After treatment theseeds were placed in the germinator along with controls. Thegermination of seeds with and without pericarp was alsoinvestigated in the field (late fall sowing). It was found thatthe pericarp caused dormancy. In seeds without pericarp,cold-moist and warm-moist stratification both proved to besuccessful in breaking embryo dormancy (100% and 96% successrespectively). The required stratification duration was 50 daysfor the warm-moist and 60 days for the cold-moist treatments.During the cold-moist stratification no germination was observed.On the other hand, seeds started to germinate during thewarm-moist stratification by about the 50th day. In the fallsowing germination was 20% for seeds with pericarp and 41% for seeds without pericarp. Drying bay laurel seeds caused areduction of the seed germination. 相似文献
145.
Marios Trigkas Christos Anastopoulos Ioannis Papadopoulos Dimitra Lazaridou 《Journal of Sustainable Forestry》2020,39(3):259-282
ABSTRACTForest cooperatives are essentially a form of entrepreneurship. However, they are confronted by various problems and they cannot pay enough attention to value creation. The aim of this paper is twofold: (a) the identification of the structural factors supporting the function of Greek forest cooperatives and the exploration of the possibilities of applying business model innovation to them; (b) the investigation of how the development of an integrated business model can help cooperatives stay ahead in the innovation game, while securing sustainability. By applying business modeling procedures to the forest cooperatives of the Region of Thessaly (Greece) this paper presents, the implementation of innovative development strategy, within the current legislative framework. Results show that the business model approach gives them the ability to develop a shared vision for value creation and delivering through the establishment of a framework related to sustainable forest management based on creation of bonds for achieving a win-win strategy, satisfying the increasing needs for innovative forest-based products, which constitutes a challenge for the sustainable management of forests. We argue that this is the first time this approach has been made regarding forest cooperatives in Greece in relation to the emerging parameters of the general business environment. 相似文献
146.
Screw withdrawal capacity used in the eccentric joints of cabinet furniture connectors in particleboard and MDF 总被引:1,自引:0,他引:1
Eccentric joints are commonly used to join particleboard and medium-density fiberboard (MDF) in cabinet furniture construction.
Screws and screws with plastic sockets are offered by many manufacturers for these kinds of joints, yet little information
is available concerning their withdrawal capacity in these materials. Research reported here indicates that face withdrawal
strengths of the screws differ slightly from manufacturer to manufacturer in particleboard and MDF, whereas withdrawal strengths
of screws with plastic sockets differ greatly from one manufacturer to another. Furthermore, the withdrawal capacity of the
screws was found to correlate with the density of both particleboard and MDF. 相似文献
147.
148.
Chrisa K Doxa Ioannis E Papadakis Pascal Divanach Maroudio Kentouri 《Aquaculture Research》2011,42(11):1623-1631
Red porgies (Pagrus pagrus) of 20.6±1.5 g mean weight were reared in tanks under four delayed self‐feeding conditions (0=control, 7, 30 and 90 s) after rod activation. The time intervals were chosen to simulate the time taken for a commercial pelleted feed to transit the tube linking a surface‐mounted feed hopper and the depth at which a cage might be submerged. Daily feeding rate, growth, food conversion index and condition factor were quite similar but fish behaviour differed among conditions. Fish remained close to the feeding point in the first two treatments (0 and 7 s delay) but foraged more widely in the remaining treatments (30 and 90 s delay), only reconsolidating around the feeding point a few seconds before feed was released. Results are discussed in relation to learning capacity and adaptation of fish to feeding behaviour flexibility, in order to develop reliable self‐feeding systems suitable for submerged cages. 相似文献
149.
Christos Noulas Ioannis Alexiou Juan M. Herrera Peter Stamp 《Journal of plant nutrition》2013,36(8):1201-1218
Field experiments were conducted for two years to compare and identify bread spring wheat (Triticum aestivum L.) genotypes which make the most efficient use of nitrogen (N). Such information is required for breeding strategies to reverse the negative relationship between yield and protein content. Three Swiss spring wheat cultivars (‘Albis’, ‘Toronit’, ‘Pizol’) and an experimental line (‘L94491’) were grown without (N0; 0 kg N ha?1) and with high fertilizer N [(NH4NO3); (N1; 250 kg N ha?1) supply on a clay loam soil with low organic matter content. Biomass and nitrogen accumulation in biomass as well as the leaf growth and senescence patterns (SPAD) were investigated in an attempt to explain the physiology of growth and N translocation of these genotypes. The pre-anthesis accumulation of biomass and N in the biomass depended on genotype only at N1 in 2000. In this year, conditions were less favorable for the pre-anthesis accumulation of biomass and N, which was, on average, 10 and 20% lower, respectively, of the total than in 1999. The contribution of pre-anthesis assimilates to the grain yield (CPAY) was higher in 1999 for all genotypes (36.9%) compared to 2000 (13.5%) except ‘Toronit’. Between anthesis and maturity the climate influenced the genetic variability of some N use efficiency components: N translocation efficiency (NTE) and dry matter translocation efficiency (DMTE). NTE was higher in 1999 (68.1%) compared to 2000 (50.7%); 1999 was a year in which the post-anthesis period was drier and warmer than usual. ‘Toronit’ produced the highest biomass by maturity due mainly to greater and longer lasting green leaf area after anthesis. ‘Albis’ performed relatively well under low input conditions, with considerable amounts of N being re-translocated to the seeds at maturity (NHI), whereas ‘Pizol’ accumulated in grains N as high as for ‘L94491’. In a humid temperate climate breeding for greater N uptake and partitioning efficiency may be a promising way to minimize N losses and produce high phytomass and grain yields. Using high protein lines as selection material and combining them with high biomass genotypes may lead to high protein contents without decreasing yield. 相似文献