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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jenvman.2006.04.026 Byline: X.F. Chen (a)(b), J.M. Chen (c), S.Q. An (b), W.M. Ju (c) Keywords: BEPS-terrain lab; Net primary productivity; Topography Abstract: Local topography significantly affects spatial variations of climatic variables and soil water movement in complex terrain. Therefore, the distribution and productivity of ecosystems are closely linked to topography. Using a coupled terrestrial carbon and hydrological model (BEPS-TerrainLab model), the topographic effects on the net primary productivity (NPP) are analyzed through four modelling experiments for a 5700km.sup.2 area in Baohe River basin, Shaanxi Province, northwest of China. The model was able to capture 81% of the variability in NPP estimated from tree rings, with a mean relative error of 3.1%. The average NPP in 2003 for the study area was 741gCm.sup.-2 yr.sup.-1 from a model run including topographic effects on the distributions of climate variables and lateral flow of ground water. Topography has considerable effect on NPP, which peaks near 1350m above the sea level. An elevation increase of 100m above this level reduces the average annual NPP by about 25gCm.sup.-2. The terrain aspect gives rise to a NPP change of 5% for forests located below 1900m as a result of its influence on incident solar radiation. For the whole study area, a simulation totally excluding topographic effects on the distributions of climatic variables and ground water movement overestimated the average NPP by 5%. Author Affiliation: (a) International Institute of Earth System Science, Nanjing University, Nanjing 210093, China (b) School of Life Science, Nanjing University, Nanjing 210093, China (c) Department of Geography and Program in Planning, University of Toronto, 100 St.George St., Room 5047,Toronto, Ont., Canada M5S 3G3 Article History: Received 30 May 2005; Revised 18 March 2006; Accepted 18 April 2006

ABSTRACT--In this paper we present an experimental investigation of the identification of crack location and size. By providing the first three natural frequencies through vibration measurements, curves of crack equivalent [...]

Eight new mutants in soybean were isolated at the K2 Mdh-1-n y20 chromosomal region. Genetic type T234 is yellow foliage and Mandell is green foliage, and they were isolated by screening germplasm for malate dehydrogenase variants. Each of the Mdh1 null mutants were allelic at the Mdh1-n locus. Gene symbols have been proposed for the new mutants and the y15 original gene symbol for T234 was deleted.

A study was conducted to analyze genetic recombinations between the k2 and Mdh1-n y20 loci in soybean in repulsion and coupling phases. A recombination rate was determined between the k2 and Mdh1-n y20 loci in several families with tan saddle seed coats. Results indicated an excess of the recombinants in repulsion phase that was correlated with breakage at the k2 Mdh1 Y20 chromosomal region. Findings also showed a minimized viability in the yellow follage plants resulting from cross combinations in both phases.

Linkage relationships between the Fr3 loci (root fluorescence) and Ap (acid phosphatase) in the soy bean were studied. Genetic stocks and their genotypes used for the experiment were Clark-ti x Hark-Fr3, and Norredo x Hark-Fr3. The Fr3, Ap, Ti, and Lap1 loci gene order and recombination values were established, with acid phosphatase the most distal marker in the a2 linkage group.

Three tan saddle seed coat (k2) mutants and three mutants of malate dehydrogenase 1 null (Mdh1-n) are allelic, in soybean, Glycine max (L.) Merr. The loci k2 and Mdh1-n are tightly linked and separated by about 1 plus or minus 1.36 cM. Inheritance studies of k2 and Mdh1-n show that they are inherited as single nuclear recessive alleles. A cross between genetic type T261 and wild type gives a recombination rate of about 1 plus or minus 1.36% in the coupling phase. No recombinants are obtained in the repulsion phase in the cross between a plant having k2 and the other having Mdh1-n.