Initial solar irradiance determinations from nimbus 7 cavity radiometer measurements

Preliminary results from solar radiation measurements from the earth radiation budget experiment on the Nimbus 7 satellite yield a mean value of 1376.0 watts per square meter for the "solar constant" from 16 November 1978 to 15 May 1979. The observed variability (root-mean-square deviation) is +/- 0.73 watt per square meter (+/- 0.05 percent) for the period.     

Changing patterns of water distribution under the influence of land reforms and simultaneous WUA establishment

In 2005 the Uzbek government accelerated the dissolution process of collective farms through full-scale land reform. As the central production unit, the collective enterprise was supplanted by a private, family-based enterprise. Simultaneously Water Users Associations (WUAs) were established that operate and maintain the irrigation and drainage infrastructure of the former collective farms. Though these land-cum-water reforms could in principle initiate enormous changes, there is still a strong continuity due to the state-regulated agricultural system. Although officially only cotton and wheat production are still subject to a state order system, the whole agricultural production is still under strict state control. This paper builds on research conducted during the spring and summer of 2005 and 2006 in the oasis of Khorezm, Uzbekistan. Through field walks in combination with semi- and non-structured interviews, two cases of water management at former collective farm (FCF) level were distinguished: one at the onset of reform and one two years after full-scale reforms. The former shows the strong interlinkage at FCF level between the control of agricultural production and water management. However, the second case shows that even in the post-reform context, where the co-ordination of production and the control of cropping areas are formally no longer arranged at this level, these functions are informally reproduced through the new institutions. The WUA forms a crucial link between privatised producers and a state preoccupied with control.     

Impact of faunal complexity on microbial biomass and N turnover in field mesocosms from a spruce forest soil

In a field study using soil mesocosms in an acid spruce forest soil we investigated the effects of mesofauna and macrofauna on microbial biomass, dissolved organic matter, and N cycling. Intact soil monoliths were taken from the ground, defaunated by deep-freezing, and wrapped in nets of various mesh-sizes to control re-immigration of different faunal size-classes. The monoliths were then replanted in the field. Three treatments of mesocosms were prepared: (1) with only microbiota, (2) microbiota and mesofauna, and (3) microbiota, mesofauna, and macrofauna (= complex fauna). After 8 months of exposure the mesocosms and the unmanipulated control plots (treatment 4) were destructively sampled. We estimated microbial biomass by substrate-induced respiration and the chloroform fumigation-extraction method. N cycling was measured by monitoring microbial N mineralization, the NH _inf4 ^sup+ content, and selected amino acids and the activities of protease, urease, and deaminase. The results from the L/F layer showed that the pool of the microbial biomass was not changed by the activity of the mesofauna. However, the mesofauna and macrofauna together enhanced SIR. An increase in microbial N mineralization was only observed in treatment 3 (microbiota + complex fauna). Protease activity and NH _inf4 ^sup+ content increased in treatments 2 (microbiota + mesofauna) and 3 (microbiota + complex fauna). The complex fauna induced a soil pH increase in treatment 3 as opposed to treatment 1 and the control. This increase was presumably due to excretory NH _inf4 ^sup+ . Principal component analysis revealed that the complex fauna in treatment 3 caused a significantly higher N turnover per unit of microbial biomass.     

Effects of ammonia,ammonium sulphate and sulphur dioxide on the frost sensitivity of scots pine (Pinus sylvestris L.).

The deterioration of forest vitality has been at least partly attributed to air pollution. Especially NH₃, originating from intensive livestock farming and locally deposited in high concentrations, may contribute to forest decline in The Netherlands. Therefore, the effect of NH₃ and SO₂ fumigations on cold stress and water stress of Pinus svlvestris were examined. P. sylvestris trees (3 yr old) were exposed to ambient air supplemented with several NH₃ concentrations, with SO₂ or a combination of NH₃ and SO₂.Tops of branches were then exposed to various subzero temperatures and the effect of air pollution on frost damage was examined. Neither ambient air, NH₃ or SO₂ significantly influenced from sensitivity at –4 or –7°C. Following freezing treatments of –10°C, the influence of NH₃ and SO₂ became apparent. The effect of the combination of these pollutants is synergistic. Exposure to NH₃ alone followed by freezing temperatures lower than –10°C resulted in more severe frost damage in early autumn and spring than in the winter. It also increased the susceptibility of P. sylvestris to water stress. A greater loss of water was observed in NH₃-fumigated needles following drought stress, suggesting increased cuticular transpiration. Bud burst and subsequent shoot growth was also strongly reduced by NH₃ fumigations.     

Interactions between wild and cultivated carrots (Daucus carota L.) in the Netherlands

Summary An investigation was made into the causes why bolters occur in carrot cultivation. In the first year of cultivation blooming plants are the result of a gene flow from wild to cultivated carrots. Hybridization may occur in areas where cultivated carrots are grown for seed production. Apart from bolters producing inedible roots such hybridization also causes a decline in quality of cultivated carrots in general. Small changes in morphological and phenological characteristics of the wild carrot are due to introgression from the cultivated carrot.     

The selection of pulses in Suriname

The consumption of pulses in Suriname amounts to an annual value of about Sf 600,000, of which two thirds represent the value of importations. There is a long standing wish to reduce imports by increasing the production and consumption of local products. The article describes the many previous attempts to establish reliable methods of cultivation, which failed because of unpredictable rainfall and the very heavy clay soil which remains waterlogged for a long time after a shower. A method introduced recently, viz. of planting pulses on ridges, has shown promising results since it avoids the difficulties of soil management. However, this method used in several experiments, needs to be adapted to the agricultural conditions of the small-holders. If the majority of rice farmers would successfully adopt this method, production could be raised to supersede the local demand by many times so that the product could be sold abroad. The selection program of pulses should then proceed as follows:

1. 1.
   to ascertain which pulses are in constant demand by the world market     

AFLP analysis of genetic diversity in leafy kale (<Emphasis Type="Italic">Brassica oleracea</Emphasis> L. convar. <Emphasis Type="Italic">acephala</Emphasis> (DC.) Alef.) landraces,cultivars and wild populations in Europe

AFLP markers were used to characterize diversity and asses the genetic structure among 17 accessions of kale landraces, cultivars and wild populations from Europe. The range of average gene diversity in accessions was 0.11–0.27. Several landraces showed higher levels of diversity than the wild populations and one cultivar had the lowest diversity measures. The landraces that were most genetically diverse were from areas where kales are known to be extensively grown, suggesting in situ conservation in these areas as a supplement to storage of seeds in gene banks. An analysis of molecular variance (AMOVA) showed that 62% of the total variation was found within accessions. For most accessions, genetic distance was not related to geographic distance. Similarities among accessions were probably not caused by recent gene flow since they were widely separated geographically; more likely the relationship among them is due to seed dispersal through human interactions. Our results indicate that a kale population found in a natural habitat in Denmark was probably not truly wild but most likely an escape from a cultivated Danish kale that had subsequently become naturalized.     

Cross-linking behavior and foaming properties of bovine α-lactalbumin after glycation with various saccharides

α-Lactalbumin was glycated via the Maillard reaction in the dry state using various mono- and oligosaccharides. The reaction resulted not only in coupling of the saccharides to α-lactalbumin but also in cross-linked proteins. The glycation rate and the extent of cross-link formation were highly dependent on the saccharide used. Glycation by arabinose and xylose led to a very fast protein cross-link formation, whereas glucose showed a relatively low protein cross-linking ability. The stability of foams, created using the various glycated protein samples, depended on the type of saccharide used, the extent of glycation, and possibly the amount of cross-linked protein. Compared to nonmodified α-lactalbumin, glycation with rhamnose and fucose improved foam stability, whereas application of glucose, galacturonic acid, and their oligosaccharides did not exert a clear effect. Mass spectrometric analysis revealed that dehydration of the Amadori products is an indicator of the formation of protein cross-links.     

Effects of pecking incentives during rearing on feather pecking of laying hens.

1. Additional straw or grain was supplied to hens during rearing in floor pens with litter floors. During lay, hens were housed in pens with partly-littered partly-slatted floors. The effects on foraging behaviour and feather pecking were studied and feather damage was scored at 17, 30 and 42 weeks of age. 2. Supply of grain in the litter during rearing caused an increase in ground scratching. Ground pecking also tended to increase. Supply of straw had no significant effect on the observed behaviours. 3. Feather damage in the laying period was significantly reduced by providing grain during rearing. A similar tendency was found for groups that received straw during rearing. On the basis of the behavioural observations it was concluded that this better plumage cover was caused by less feather pecking. 4. The frequency of pecking at food was decreased during rearing by the supply of grain. This could not be explained solely on the basis of a lower food intake. Apparently the efficiency of pecking at food had changed as well. Behavioural data from the laying period suggest that this change was of a more permanent character. 5. The incentive value of the ground and the substrate covering it might be increased by the supply of grain during the rearing period. This causes foraging-related behaviours like scratching and pecking to be directed to the ground. The hens' perception of incentive stimuli for pecking is apparently influenced by experience during rearing. 6. To prevent birds redirecting their ground pecks to the feathers of other birds, not only the peckability/scratchability of the ground seems to be important but also other aspects like nutritive value or taste.