7 research outputs found

    Volcanic fertilization of Balinese rice paddies

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    Abstract Since the advent of high-yielding ''Green Revolution'' rice agriculture in the 1970s, Balinese farmers have been advised to supply all the potassium and phosphate needed by rice plants via chemical fertilizers. This policy neglects the contribution of minerals leached from the volcanic soil and transported via irrigation systems. We documented frequent deposition of volcanic ash deposits to rice producing watersheds. Concentrations of phosphorus in rivers were between 1 and 4 mg l − 1 PO 4 , increasing downstream. We measured extractable potassium and phosphate levels in the soils of unfertilized Balinese rice paddies, and found them to be indistinguishable from those in fertilized paddies, and sufficient for high grain yields. Field experiments varying phosphorus applications to rice fields from 0 to 100 kg superphosphate per hectare (7-26 kg P ha − 1 ) demonstrated small increases in harvest yields only with the smallest additions. Direct measurements of PO 4 in irrigation waters indicate that most of the added phosphate flows out of the paddies and into the river systems, accumulating to very high levels before reaching the coast

    Erratum: Corrigendum: Sequence and comparative analysis of the chicken genome provide unique perspectives on vertebrate evolution

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    International Chicken Genome Sequencing Consortium. The Original Article was published on 09 December 2004. Nature432, 695–716 (2004). In Table 5 of this Article, the last four values listed in the ‘Copy number’ column were incorrect. These should be: LTR elements, 30,000; DNA transposons, 20,000; simple repeats, 140,000; and satellites, 4,000. These errors do not affect any of the conclusions in our paper. Additional information. The online version of the original article can be found at 10.1038/nature0315

    A study of the influence of environmental factors on the nightly emergence of the Little Brown Bat, Myotis lucifugus while noting clustering patterns.

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    We observed the effects of the abiotic factors temperature, light intensity, humidity, wind and time of sunset on the time of first nightly emergence grouping patterns and their relation to emergence time. Three roosts were observed for a week, nightly from 8:45pm to 10:15pm. Measurements of the environmental factors in question were taken at set time intervals throughout the night and at the time of first emergence. The time of first emergence differed significantly between roosts, as did the light levels at emergence. There was no significant correlation between time of first emergence and any of the abiotic variables except time to sunset. We also found that bats tend emerge in clusters, and that these group emergences were more frequent before light intensity reached 0 lux.http://deepblue.lib.umich.edu/bitstream/2027.42/54685/1/3125.pdfDescription of 3125.pdf : Access restricted to on-site users at the U-M Biological Station

    Generation and annotation of the DNA sequences of human chromosomes 2 and 4

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    Sequence and comparative analysis of the chicken genome provide unique perspectives on vertebrate evolution

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    We present here a draft genome sequence of the red jungle fowl, Gallus gallus. Because the chicken is a modern descendant of the dinosaurs and the first non-mammalian amniote to have its genome sequenced, the draft sequence of its genome--composed of approximately one billion base pairs of sequence and an estimated 20,000-23,000 genes--provides a new perspective on vertebrate genome evolution, while also improving the annotation of mammalian genomes. For example, the evolutionary distance between chicken and human provides high specificity in detecting functional elements, both non-coding and coding. Notably, many conserved non-coding sequences are far from genes and cannot be assigned to defined functional classes. In coding regions the evolutionary dynamics of protein domains and orthologous groups illustrate processes that distinguish the lineages leading to birds and mammals. The distinctive properties of avian microchromosomes, together with the inferred patterns of conserved synteny, provide additional insights into vertebrate chromosome architecture

    Generation and annotation of the DNA sequences of human chromosomes 2 and 4

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