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991.
David Nicholas Barton Ståle Navrud Heid Bjørkeslett Ingrid Lilleby 《Journal of Soils and Sediments》2010,10(2):186-201
Purpose
As input to a cost-benefit analysis of large-scale remediation measures of contaminated sediments in the Grenland fjords in Norway, we conducted a contingent valuation (CV) survey of a representative sample of households from municipalities adjacent to these fjords. 相似文献992.
Yang Yang Yuezhi Pan Xun Gong Moutian Fan 《Genetic Resources and Crop Evolution》2010,57(8):1239-1248
Citrus hongheensis is a critically endangered species endemic to the Honghe river region in southeastern Yunnan, China. Its genetic diversity
and differentiation were investigated using Inter-Simple Sequence Repeat (ISSR) markers. One hundred primers were screened,
and a total of 245 loci were amplified from seven natural populations by 13 informative and reliable primers. Of these 245
ISSR loci, 233 were polymorphic and the detected variations revealed a relatively high level of intraspecific genetic diversity.
At the population level, the mean percentage of polymorphic loci (PPB) was 36.50%, while the average expected heterozygosity (He) and Shannon diversity index (Ho) were 0.1327 and 0.1972, respectively. At the species level (across all populations), PPB was 95.10%, while He and Ho were 0.3520 and 0.5195, respectively. A high Gst value (0.6247) indicated that there is significant differentiation among populations, which was confirmed by AMOVA analysis
(Φst = 0.6420). Pairwise genetic identity (I) values among populations ranged from 0.6341 to 0.7675, with a mean of 0.7008. We propose that the high level of genetic
differentiation may be the result of habitat fragmentation and limited gene flow (Nm = 0.1502). For effective in situ conservation and population restoration of C. hongheensis it will be important to maintain historical processes, including high outbreeding rates, sufficient gene flow, and large
effective population sizes. 相似文献
993.
Cindy L. Yu Jason C. Legg 《Journal of Agricultural, Biological & Environmental Statistics》2010,15(2):139-157
The National Resources Inventory (NRI) is a large-scale longitudinal survey conducted to assess trends and conditions of nonfederal
land. A key NRI estimate is year-to-year change in acres of developed land, where developed land includes roads and urban
areas. In 2003, a digital data collection procedure was implemented replacing a map overlay. Data from an NRI calibration
experiment are used to estimate the relationship between data collected under the old and new protocols. A measurement error
model is postulated for the relationship, where duplicate measurements are used to estimate the error variance of the new
procedure. If any significant discrepancy is detected between new and old measures, some parameters that govern the algorithm
for the new protocol can be changed to alter the relationship. Parameters were initially calibrated so overall averages nearly
match for the new and old protocols. Analyses on the data after initial parameter calibration suggest that a line with an
intercept of 0 and a slope of 1 is an acceptable representation for the relationship between the two determinations. Estimation
of the measurement error variances as functions of the proportion of developed land are also given. 相似文献
994.
Richard Huggins Yan Wang Joanne Kearns 《Journal of Agricultural, Biological & Environmental Statistics》2010,15(3):279-289
Estimating equations give a flexible method of inference when the likelihood is either intractable or is not fully specified.
Here we consider a batch marking experiment where the full likelihood is complex and without resorting to devices such as
the computationally intensive expectation-maximization (EM) algorithm is intractable. However, a pseudo-likelihood that yields
tractable estimating equations may be easily constructed and its effectiveness is demonstrated via simulation studies. The
methodology was applied to study the abundance of Oriental weatherloach in a waterbody in South-Eastern Australia. The programs
and data set used in this article are available in the online supplements. 相似文献
995.
Spatial distribution of sediments and transfer properties in soils in a stormwater infiltration basin 总被引:1,自引:2,他引:1
Patrice Cannavo Laure Vidal-Beaudet Béatrice Béchet Laurent Lassabatère Sylvain Charpentier 《Journal of Soils and Sediments》2010,10(8):1499-1509
Purpose
The aim of our study was to characterise the heterogeneity of sediment distribution in a stormwater retention/infiltration basin (Pont de Cheviré, Nantes, France) and to determine the impact of this distribution on water transfer properties in the soil. 相似文献996.
Saowaluck Bua-in Yingyong Paisooksantivatana 《Genetic Resources and Crop Evolution》2010,57(3):405-414
The genetic relatedness among 51 accessions, 14 species of the genus Zingiber and genetic variability of a clonally propagated species, Zingiber montanum (Koenig) Link ex Dietr., from Thailand were studied using random amplified polymorphic DNA (RAPD) profiles. Twenty-nine random
primers gave reproducible amplification banding patterns of 607 polymorphic bands out of 611 scored bands accounting for 99.40%
polymorphism across the genotypes. Jaccard’s coefficient of similarity varied from 0.119 to 0.970, indicative of distant genetic
relatedness among the genotype studied. UPGMA clustering indicated eight distinct clusters of Zingiber, with a high cophenetic correlation (r = 1.00) value. Genetic variability in Z. montanum was exhibited by the collections from six regions of Thailand. High molecular variance (87%) within collection regions of
Z. montanum accessions was displayed by AMOVA and also explained the significant divergence among the sample from six collection regions.
Our results indicate that RAPD technique is useful for detecting the genetic relatedness within and among species of Zingiber and that high diversity exists in the clonally propagated species, Z. montanum. 相似文献
997.
Andrea R. Litt Robert J. Steidl 《Journal of Agricultural, Biological & Environmental Statistics》2010,15(2):228-247
Inferences about abundance often are based on unadjusted counts of individuals observed, in part, because of the large amount
of data required to generate reliable estimates of abundance. Where capture-recapture data are sparse, aggregating data across
multiple sample elements by pooling species, locations, and sampling periods increases the information available for modeling
detection probability, a necessary step for estimating abundance reliably. The process of aggregating sample elements involves
balancing trade-offs related to the number of aggregated elements; although larger aggregates increase the amount of information
available for estimation, they often require more complex models. We describe a heuristic approach for aggregating data for
studies with multiple sample elements, use simulated data to evaluate the efficacy of aggregation, and illustrate the approach
using data from a field study. Aggregating data systematically improved reliability of model selection and increased accuracy
of abundance estimates while still providing estimates of abundance for each original sample unit, an important benefit necessary
to maintain the design and sampling structure of a study. Within the framework of capture-recapture sampling, aggregating
data improves estimates of abundance and increases the reliability of subsequent inferences made from sparse data. Additional
tables and datasets may be found in the online supplements. 相似文献
998.
Anna A. Filatenko Karl Hammer Sulaiman Al Khanjari Andreas Buerkert 《Genetic Resources and Crop Evolution》2010,57(8):1135-1139
Due to its geographic position on the northeastern tip of the Arabian Peninsula and its sea trade relationships with Asia,
East Africa and the Middle East, Oman has for millennia been at the cross-roads of inter-regional exchange of cultivated plants.
This is reflected in recent findings of new cultivars of banana (Musa spp.) and wheat (Triticum spp.) in remote oases of the Hajar Mountains in northern Oman. Material collected in 2003 and 2004 contained six new botanical
varieties of wheat which are described here. One of them belongs to the tetraploid T. aethiopicum, the others are hexaploid. 相似文献
999.
Jiaguo Jiao Erle C. Ellis Ian Yesilonis Junxi Wu Hongqing Wang Huixin Li Linzhang Yang 《Journal of Soils and Sediments》2010,10(3):461-472
Purpose
Village landscapes, which integrate small-scale agriculture with housing, forestry and a host of other land use practices, cover more than 2 × 106 km2 across China. Village lands tend to be managed at very fine spatial scales (≤30 m), with managers altering soil fertility and even terrain by terracing, irrigation, fertilizing, and other land use practices. Under these conditions, accumulation of excess phosphorous in soils has become important contributor to eutrophication of surface waters across China’s densely populated village landscapes. The aim of this study was to investigate relationships between fine-scale patterns of agricultural management and soil total phosphorus (STP) within China’s village landscapes. 相似文献1000.
Xing-Pu Li Su-Que Lan Ye-Lun Zhang Yu-Ping Liu 《Genetic Resources and Crop Evolution》2010,57(7):1007-1012
Pericarp color in wheat is an important trait related to nutrients and health benefits. Identification of molecular markers closely linked to the grain color genes will help utilize pericarp trait in wheat breeding. Genetic studies involving F1, F2, and F3 populations from the cross Jizi 439 (purple grain)/Gao8901 (white grain) showed that the purple grain color was controlled by two genes. By using the bulked segregant analysis (BSA) approach, two DNA pools were established from the dark purple-grain and white-grain plants respectively. Among the 230 pairs of microsatellite primers used in this study, two markers showed polymorphism in DNA pools, parents, F1 and F2 populations. Linkage analysis indicated that the two markers Xgwm47 and Xgwm155 were linked with two purple pigment genes. One of the purple pigment genes is located on chromosome 2AS and is 34.7cM away from the marker Xgwm47, whereas another gene is mapped on 3AL with 14.7cM away from marker Xgwm155. 相似文献