‘Ecological forestry’ and eucalypt forests managed for wood production in south-western Australia     

Geoff L. Stoneman 《Biological conservation》2007,137(4):558-566

The model of ‘ecological forestry’ has evolved as a part of the development of the concept of ecosystem management. ‘Ecological forestry’ emphasises that manipulation of a forest ecosystem should consider, and as far as practicable work within the limits of, natural disturbance patterns prior to extensive human alteration of the landscape. This paper evaluates the extent to which forest management practices in jarrah (Eucalyptus marginata) and karri (Eucalyptus diversicolor) forests of south-western Australia align with this view of the characteristics and appropriate silviculture of ‘ecological forestry’. Characteristics and appropriate silviculture of ‘ecological forestry’ are evaluated in relation to (i) the stand level decisions of stand structure and harvest timing and (ii) the landscape level decisions of harvest levels and age structures, and spatial patterns of harvest. Forest management in south-western Australia is found to align with appropriate silviculture under this model of ‘ecological forestry’. Additionally, the landscape triad of areas managed to ‘ecological forestry’ principles, conservation reserves and areas managed to production forestry is in place in the south-western forests of Australia. Strengths and weaknesses in the model of ‘ecological forestry’ and the ability to interpret consistency of practices in the forests of south-western Australia with the characteristics of ‘ecological forestry’ are identified.  相似文献   

Comparison of phospholipid fatty acid (PLFA) and total soil fatty acid methyl esters (TSFAME) for characterizing soil microbial communities     

Rebecca E. Drenovsky  Geoff N. Elliott  Kate M. Scow 《Soil biology & biochemistry》2004,36(11):1793-1800

Phospholipid fatty acid (PLFA) and total soil fatty acid methyl esters (TSFAME), both lipid-based approaches used to characterize microbial communities, were compared with respect to their reliable detection limits, extraction precision, and ability to differentiate agricultural soils. Two sets of soil samples, representing seven crop types from California's Central Valley, were extracted using PLFA and TSFAME procedures. PLFA analysis required 10 times more soil than TSFAME analysis to obtain a reliable microbial community fingerprint and total fatty acid content measurement. Although less soil initially was extracted with TSFAME, total fatty acid (FA) content g⁻¹ soil (DW) was more than 7-fold higher in TSFAME- versus PLFA-extracted samples. Sample extraction precision was much lower with TSFAME analysis than PLFA analysis, with the coefficient of variation between replicates being as much as 4-fold higher with TSFAME extraction. There were significant differences between PLFA- and TSFAME-extracted samples when biomarker pool sizes (mol% values) for bacteria, actinomycetes, and fungi were compared. Correspondence analysis (CA) of PLFA and TSFAME samples indicated that extraction method had the greatest influence on sample FA composition. Soil type also influenced FA composition, with samples grouping by soil type with both extraction methods. However, separate CAs of PLFA- and TSFAME extracted samples depicted strong differences in underlying sample groupings. Recommendations for the selection of extraction method are presented and discussed.  相似文献   

Influences of Aporrectodea trapezoides and A. rosea (Lumbricidae) on the uptake of nitrogen and yield of oats (Avena fatua) and lupins (Lupinus angustifolius): The 7th international symposium on earthworm ecology · Cardiff · Wales · 2002     

Geoff H. Baker  Maurice Amato  Jeff Ladd 《Pedobiologia》2003,47(5-6):857-862

  相似文献   

Characterization and content of flavonoid glycosides in genetically modified tomato (Lycopersicon esculentum) fruits   总被引：7，自引：0，他引：7  

Le Gall G  DuPont MS  Mellon FA  Davis AL  Collins GJ  Verhoeyen ME  Colquhoun IJ 《Journal of agricultural and food chemistry》2003,51(9):2438-2446

  相似文献   

Kinetic analysis of nonisothermal differential scanning calorimetry of 1,3-dipalmitoyl-2-oleoylglycerol     

Smith KW  Cain FW  Talbot G 《Journal of agricultural and food chemistry》2005,53(8):3031-3040

The crystallization of fats has been extensively studied because of its importance in the processing of food and food ingredients. Differential scanning calorimetry (DSC) is widely used in such studies. The aim of this study was to examine the determination of kinetic parameters from nonisothermal DSC crystallization of a model fat, 1,3-dipalmitoyl-2-oleoylglycerol. We applied peak and isoconversional methods to determine activation energies and compared these techniques with a nonparametric method, which separates the temperature dependence and degree of crystallization dependence of the crystallization rate. The Johnson-Mehl-Avrami-Erofeyev-Kolmogorov (JMAEK) model provided the best fit to the data, while the temperature dependence of the rate constant was best explained by a Vogel-Fulcher relationship, where the reference temperature was the melting point of the crystallizing species.  相似文献   

Epigeic spiders as ecological indicators of conservation value for peat bogs     

Alan G. Scott  Geoff S. Oxford 《Biological conservation》2006,127(4):420-428

  相似文献   

Associations among echocardiography,cardiac biomarkers,insulin metabolism,morphology, and inflammation in cats with asymptomatic hypertrophic cardiomyopathy     

Ingrid van Hoek  Hannah Hodgkiss-Geere  Elizabeth F. Bode  Julie Hamilton-Elliott  Paul Mõtsküla  Valentina Palermo  Yolanda M. Pereira  Geoff J. Culshaw  Anna Ivanova  Jo Dukes-McEwan 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2020,34(2):591-599

  相似文献   

Feline cerebrovascular disease: clinical and histopathologic findings in 16 cats     

Altay UM  Skerritt GC  Hilbe M  Ehrensperger F  Steffen F 《Journal of the American Animal Hospital Association》2011,47(2):89-97

Sixteen cats with cerebrovascular disease confirmed via histology to be of nontraumatic and nonneoplastic origins are described. In addition, the anatomy of the arterial supply of the cat's brain is reviewed. It is suggested that this unique arterial design may influence the incidence of cerebrovascular accidents in this species. Of the 16 cats reviewed, seven cats had ischemic infarctions, five had hemorrhagic infarctions, and four were diagnosed with intracranial hemorrhage. The median age was 8 yr and 9.5 yr in cats with infarctions and intracranial hemorrhages, respectively. Clinical signs were severe, acute, consistent with the localization of the cerebrovascular lesion, and influenced by underlying pathology. Four cats with infarction showed lateralized neurologic signs. Four cats with infarctions were diagnosed with pulmonary disease antemortem and three cats had hyperthyroidism. Cerebrospinal fluid analysis and computed tomography scans were available in two cats. None of the infarctions were grossly visible. All cats with hemorrhagic infarcts had severe liver pathology and nephritis was identified in four cats. Hypoxia was a feature in four cats and one cat suffered cardiac failure. In conclusion, the clinical picture is influenced by the type of cerebrovascular disease, the localization of the intracranial lesions, and any underlying pathology.  相似文献   

5th International Conference on Mycobacterium bovis. Preface     

Fairbrother P  Crews K  Livingstone P  Buddle B  de Lisle G  Collins D  Nugent G 《Veterinary microbiology》2011,151(1-2):1

  相似文献   

Restoring longleaf pine (Pinus palustris Mill.) in loblolly pine (Pinus taeda L.) stands: Effects of restoration treatments on natural loblolly pine regeneration     

Benjamin O. KnappG. Geoff Wang  Huifeng HuJoan L. Walker  Carsyn Tennant 《Forest Ecology and Management》2011,262(7):1157-1167

Historical land use and management practices in the southeastern United States have resulted in the dominance of loblolly pine (Pinus taeda L.) on many upland sites that historically were occupied by longleaf pine (Pinus palustris Mill.). There is currently much interest in restoring high quality longleaf pine habitats to such areas, but managers may also desire the retention of some existing canopy trees to meet current conservation objectives. However, fast-growing natural loblolly pine regeneration may threaten the success of artificially regenerated longleaf pine seedlings. We evaluated the establishment and growth of natural loblolly pine regeneration following different levels of timber harvest using single-tree selection (Control (uncut, residual basal area ∼16 m²/ha), MedBA (residual basal area of ∼9 m²/ha), LowBA (residual basal area of ∼6 m²/ha), and Clearcut (complete canopy removal)) and to different positions within canopy gaps (approximately 2800 m²) created by patch cutting at two ecologically distinct sites within the longleaf pine range: Fort Benning, GA in the Middle Coastal Plain and Camp Lejeune, NC in the Lower Coastal Plain. The density of loblolly pine seedlings was much higher at Camp Lejeune than at Fort Benning at the end of the first growing season after harvesting. Following two growing seasons, there were no significant effects of canopy density or gap position on the density of loblolly pine seedlings at either site, but loblolly pine seedlings were taller on treatments with greater canopy removal. Prescribed fires applied following the second growing season killed 70.6% of loblolly pine seedlings at Fort Benning and 64.3% of seedlings at Camp Lejeune. Loblolly pine seedlings were generally less than 2 m tall, and completeness of the prescribed burns appeared more important for determining seedling survival than seedling size. Silvicultural treatments that include canopy removal, such as patch cutting or clearcuts, will increase loblolly pine seedling growth and shorten the window of opportunity for control with prescribed fire. Therefore, application of prescribed fire every 2-3 years will be critical for control of loblolly pine regeneration during restoration of longleaf pine in existing loblolly pine stands.  相似文献