Copper: An alternative to mercury; more effective than zirconium in Kjeldahl digestion of ecological materials

Jones, Martha N.; Bradshaw, H. David

doi:10.1080/00103628909368165

Cited by 18 publications

(9 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Soil OM was determined by mass loss following ignition after heating crucibles containing about 1 g of the soil at 550°C for 5 hours to consume the organic matter by oxidation ( Chapman 1976). Soil [N T ] and [P T ] were determined colorimetrically on a LACHAT flow‐injection analyzer (QuikChem AE Automated Ion Analyzer System, LACHAT ZELLWEGER Analytic Instruments Inc., Milwaukee, Wisconsin, U.S.A.) following modified micro‐Kjeldahl digestion procedures ( Parkinson & Allen 1975; Jones & Bradshaw 1989; LACHAT Instruments, Inc. 1992 a , 1992 b ).…”

Section: Methodsmentioning

confidence: 99%

Effects of Restoration Thinning on PresettlementPinus ponderosain Northern Arizona

Stone

Kolb

Covington

1999

Restoration Ecology

View full text Add to dashboard Cite

In the 100 years following the arrival of Euro-American settlers in northern Arizona, Pinus ponderosa (ponderosa pine) forests changed from open, low-density stands to closed, high-density stands. The increase in tree density has been detrimental to the vigor of old-growth trees that established before settlement (presettlement trees). In this study, we examined whether the vigor of presettlement trees could be improved by restoring the original stand structure by thinning the ponderosa pines that established after settlement (postsettlement trees). The restoration treatment caused the following changes in the presettlement trees and their environment in the first year following thinning: an increase in volumetric soil water content between May and August, an increase in predawn xylem water potential in July and August, a decrease in midday xylem water potential in June and August, an increase in net photosynthetic rate in August, an increase in foliar nitrogen concentration in July and August, and an increase in bud and needle size. The results show that the thinning restoration treatment improved the condition of presettlement ponderosa pines by increasing canopy growth and the uptake of water, nitrogen, and carbon.

show abstract

Section: Methodsmentioning

confidence: 99%

Effects of Restoration Thinning on PresettlementPinus ponderosain Northern Arizona

Stone

Kolb

Covington

1999

Restoration Ecology

View full text Add to dashboard Cite

show abstract

“…Analyses followed USEPA (1979) andAPHA (1985) procedures with digestions according to Jones & Bradshaw (1989). During the last 2 yr, urea was also measured (McCarthy 1970).…”

Section: Methodsmentioning

confidence: 99%

Multi-year distribution patterns of nutrients within the Neuse River Estuary, North Carolina

Christian¹,

Boyer²,

Stanley³

1991

Mar. Ecol. Prog. Ser.

124

View full text Add to dashboard Cite

Spabal and temporal patterns of nutnent dlstnbutions m the Neuse h v e r Estuary, North Carol~na were assessed from a 4 yr study lnvolvlng 82 longitudinal transects of the estuary T h s major nver-dominated estuary receives water from a 16 000 km2 dralnage basin and 1s connected to the Atlantic Ocean by Pamhco Sound Concentratlons of nltrogen and phosphorus species and chlorophyll a were measured in assoclabon u l t h environmental factors Intrastahon d~s t r l b u t~o n s of variables were generally non-normal and interstat~on dlstrlbutlon patterns vaned considerably between specles measured Concentrations of d~ssolved species decreased down-estuary although lnternal sources of both ammonlum and filterable reachve phosphorus were apparent Particulate specles demonstrated maxlma in the upper estuary associated with autochthonous production The relat~ve isolation of the Neuse k v e r Estualy from ocean inputs and long flushlng tlmes of freshwater provide an environment whlch promotes nonconservahve m w n g of nutrient species The average flushlng time for the estuary was 51 d providing an extended period w t h l n the estuary for substantial recycling Thus I s t n b u t l o n patterns reflect the dominance of biolog~cal and chemical achvlty except when large freshets cause r a p~d movement of water to the lower estuary and out Into Pamhco Sound

show abstract

“…Organic carbon content was analysed based on the chromic acid wet oxidation method (Walkley & Black, 1934). Total N was detected using an Auto Kjeldahl Unit model K370 (Buchi, Flawil, Switzerland;Jones & Bradshaw, 1989). Hydrolysable N was converted to ammonium by reaction with iron (II) sulfate and sodium hydroxide by a diffusion procedure.…”

Section: Chemical Analysesmentioning

confidence: 99%

16S rRNA gene analyses of bacterial community structures in the soils of evergreen broad-leaved forests in south-west China

Chan

Yang

et al. 2006

FEMS Microbiology Ecology

101

View full text Add to dashboard Cite

Bacterial community structure was studied in humus and mineral soils of evergreen broad-leaved forests in Ailaoshan and Xishuangbanna, representing subtropical and tropical ecosystems, respectively, in south-west China using sequence analysis and terminal restriction fragment length polymorphism (T-RFLP) analysis of 16S rRNA genes. Clone sequences affiliated to Acidobacteria were retrieved as the predominant bacterial phylum in both forest soils, followed by those affiliated to members of the Proteobacteria, Planctomycete and Verrucomicrobia. Despite higher floristic richness at the Xishuangbanna forest than at the Ailaoshan forest, soil at Xishuangbanna harbored a distinctly high relative abundance of Acidobacteria-affiliated sequences (80% of the total clones), which led to a lower overall bacterial diversity than at Ailaoshan. Bacterial communities in humus and mineral soils of the two forests appeared to be well differentiated, based on 16S rRNA gene phylogeny, and correlations were found between the bacterial T-RFLP community patterns and the organic carbon and nutrient contents of the soil samples. The data reveal that Acidobacteria dominate soil bacterial communities in the evergreen broad-leaved forests studied here and suggest that bacterial diversity may be influenced by soil carbon and nutrient levels, but is not related to floristic richness along the climatic gradient from subtropical to tropical forests in south-west China.

show abstract

Copper: An alternative to mercury; more effective than zirconium in Kjeldahl digestion of ecological materials

Cited by 18 publications

References 8 publications

Effects of Restoration Thinning on PresettlementPinus ponderosain Northern Arizona

Effects of Restoration Thinning on PresettlementPinus ponderosain Northern Arizona

Multi-year distribution patterns of nutrients within the Neuse River Estuary, North Carolina

16S rRNA gene analyses of bacterial community structures in the soils of evergreen broad-leaved forests in south-west China

Contact Info

Product

Resources

About