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181.
Solichin Manuri Cris Brack Teddy Rusolono Fatmi Noor’an Louis Verchot Sandhi I. Maulana Wahyu C . Adinugroho Hery Kurniawan Dian Wulansih Sukisno Gita Ardia Kusuma Arif Budiman Rahmad Supri Anggono Chairil Anwar Siregar Onrizal Onrizal Dhany Yuniati Emma Soraya 《Annals of Forest Science》2017,74(1):23
Key message
This study assessed the effect of ecological variables on tree allometry and provides more accurate aboveground biomass (AGB) models through the involvement of large samples representing major islands, biogeographical zones and various succession and degradation levels of natural lowland forests in the Indo-Malay region. The only additional variable that significantly and largely contributed to explaining AGB variation is grouping based on wood-density classes.Context
There is a need for an AGB equation at tree level for the lowland tropical forests of the Indo-Malay region. In this respect, the influence of geographical, climatic and ecological gradients needs to be assessed.Aims
The overall aim of this research is to provide a regional-scale analysis of allometric models for tree AGB of lowland tropical forests in the Indo-Malay region.Methods
A dataset of 1300 harvested trees (5 cm ≤ trunk diameter ≤ 172 cm) was collected from a wide range of succession and degradation levels of natural lowland forests through direct measurement and an intensive literature search of principally grey publications. We performed ANCOVA to assess possible irregular datasets from the 43 study sites. After ANCOVA, a 1201-tree dataset was selected for the development of allometric equations. We tested whether the variables related to climate, geographical region and species grouping affected tree allometry in the lowland forest of the Indo-Malay region.Results
Climatic and major taxon-based variables were not significant in explaining AGB variations. Biogeographical zone was a significant variable explaining AGB variation, but it made only a minor contribution on the accuracy of AGB models. The biogeographical effect on AGB variation is more indirect than its effect on species and stand characteristics. In contrast, the integration of wood-density classes improved the models significantly.Conclusion
Our AGB models outperformed existing local models and will be useful for improving the accuracy on the estimation of greenhouse gas emissions from deforestation and forest degradation in tropical forests. However, more samples of large trees are required to improve our understanding of biomass distribution across various forest types and along geographical and elevation gradients.182.
A Anwar 《British poultry science》1967,8(4):311-314
For the standardisation of rations for Fayoumi chicks, gross protein value unit (G.P.V.U.) was introduced; this was taken to mean the amount of supplementary protein that would stimulate as much growth as 3 per cent casein protein having gross protein value of 100.
Three total protein levels were tested in diets containing the same productive energy levels (1800kcal./kg.) and G.P.V.U.’s (30 per kg. of food). Since no significant differences in chick growth were recorded up to 8 weeks of age it was concluded that it is practical to adjust the energy :protein ratio between productive calories and G.P.V.U.’s per kg. of food irrespective of the total protein in the diets of growing Fayoumi chicks. 相似文献
183.
Ali Anwar Ahmad Guillaume Douay Mary-Ruth Low Suria Fabbri Hui Cheng Chen 《Veterinary anaesthesia and analgesia》2021,48(3):380-387
ObjectiveTo assess the efficacy of butorphanol–azaperone–medetomidine (BAM) and butorphanol–midazolam–medetomidine (BMM) protocols for immobilization of wild common palm civets (Paradoxurus musangus) with subsequent antagonization with atipamezole.Study designProspective, randomized, blinded clinical trial.AnimalsA total of 40 adult wild common palm civets, 24 female and 16 male, weighing 1.5–3.4 kg.MethodsThe civets were randomly assigned for anesthesia with butorphanol, azaperone and medetomidine (0.6, 0.6 and 0.2 mg kg–1, respectively; group BAM) or with butorphanol, midazolam and medetomidine (0.3, 0.4 and 0.1 mg kg–1, respectively; group BMM) intramuscularly (IM) in a squeeze cage. When adequately relaxed, the trachea was intubated for oxygen administration. Physiological variables were recorded every 5 minutes after intubation. Following morphometric measurements, sampling, microchipping and parasite treatment, medetomidine was reversed with atipamezole at 1.0 or 0.5 mg kg–1 IM to groups BAM and BMM, respectively. Physiological variables and times to reach the different stages of anesthesia were compared between groups.ResultsOnset time of sedation and recumbency was similar in both groups; time to achieve complete relaxation and tracheal intubation was longer in group BAM. Supplementation with isoflurane was required to enable intubation in five civets in group BAM and one civet in group BMM. All civets in group BAM required topical lidocaine to facilitate intubation. End-tidal carbon dioxide partial pressure was lower in group BAM, but heart rate, respiratory rate, rectal temperature, peripheral hemoglobin oxygen saturation and mean arterial blood pressure were not different. All civets in both groups recovered well following administration of atipamezole.Conclusions and clinical relevanceBoth BAM and BMM combinations were effective for immobilizing wild common palm civets. The BMM combination had the advantage of producing complete relaxation that allowed intubation more rapidly. 相似文献
184.
Wheat grain yield,phosphorus uptake and soil phosphorus fraction after 23 years of annual fertilizer application to an Andosol 总被引:1,自引:0,他引:1
A field experiment was conducted on an Andosol to evaluate wheat (Triticum aestivum L.) yield, P and N uptake and soil P fraction after long-term fertilization (no fertilizer, NPK, NP, NK and PK treatments). Application rates of N, P and K fertilizers were 100, 65 and 83 kg ha−1 year−1 by ammonium sulfate, superphosphate, and potassium chloride, respectively. Phosphorus fertilization was critical for grain yield since the NK treatment did not increase yield compared with no fertilizer treatment. Agronomic efficiency of P was greater than agronomic efficiency of N, although apparent recovery of P and N were 17 and 53%, respectively. Combination application of fertilizer P and N resulted in the greatest grain yield over 23-year cultivation. Interaction impact on grain yield between P and N ranged from 71 to 109%, and was greater than the values for cereals in the earlier works. The N/P ratios of wheat decreased by P application and increased by N application. The N/P ratios in NPK and NP treatments were higher than the values attaining maximum yield for cereal crops reported by other works. 相似文献
185.
Kazufumi?OsakoEmail author Mohammed?Anwar?Hossain Koichi?Kuwahara Yukinori?Nozaki 《Fisheries Science》2005,71(2):367-373
The cryoprotective effects of trehalose on fish myofibrillar protein were compared with those of sucrose, glucose and sorbitol.
The frozen surimi with trehalose exhibited significantly higher Ca2+-ATPase activity through-out the storage periods, resulting in higher gel-forming ability than that of without trehalose.
The amount of unfrozen water was significantly increased in the surimi upon addition of trehalose at any concentrations tested.
The findings suggest that trehalose constructed bound water molecules in protein structure, consequently suppressed freeze-induced
denaturation of protein and maintained gel-forming ability. An addition of 5.0% to 7.5% concentration of trehalose showed
threshold behavior to increase the amount of unfrozen water and to prevent freeze-induced denaturation of protein. The effects
of trehalose were almost similar to those of other sugars. 相似文献
186.
根据历年采自新疆各地区的350号木灵藓属Orthotrichum 植物标本,在查阅大量文献的基础上,通过经典分类学方法,对新疆木灵藓属植物进行了整理、鉴定和分类。结果表明:新疆有木灵藓属植物5亚属、17种,包括裸孔亚属subg. Gymnoporus (6种) 、直叶亚属subg. Orthophyllum (1种)、疣叶亚属subg. Pulchella (5种)、圆孔亚属subg. Phaneroporum (1种)、木灵藓亚属subg. Orthotrichum (4种),其中高山木灵藓Orthotrichum alpestre Hornsch. ex B.S.G为中国新记录种;中国木灵藓O. hookeri Wils. ex Mitt.、东亚木灵藓O. ibukiense Toy.、短丛木灵藓O. pumilum Sw. 和卷叶木灵藓O. revolutum C. Muell. 为新疆新记录种。通过对新疆新记录种的生境、识别特征、采集地点、地理分布、海拔等信息的整理分析,绘制了4个种的线条图,并编制了新疆木灵藓属植物的分亚属和分种检索表。 相似文献
187.
Jie Li Yuanliang Shi Jiafa Luo David Houlbrooke Stewart Ledgard Anwar Ghani Stuart Lindsey 《Journal of Soils and Sediments》2014,14(8):1341-1349
Purpose
With land application of farm effluents from cows during housing or milking as an accepted practice, there are increasing concerns over its effect on nitrogen (N) loss through ammonia (NH3) volatilization. Understanding the relative extent and seasonal variation of NH3 volatilization from dairy effluent is important for the development of management practices for reducing NH3 losses. The objectives of this study were to determine potential NH3 losses from application of different types of dairy effluent (including both liquid farm dairy effluent (FDE) and semi-solid dairy farm manure) to a pasture soil during several contrasting seasons and to evaluate the potential of the urease inhibitor (UI)—N-(n-butyl) thiophosphoric triamide (NBTPT, commercially named Agrotain®) to reduce gaseous NH3 losses.Material and methods
Field plot trials were conducted in New Zealand on an established grazed pasture consisting of a mixed perennial ryegrass (Lolium perenne L.)/white clover (Trifolium repens L.) sward. An enclosure method, with continuous air flow, was used to compare the effects of treatments on potential NH3 volatilization losses from plots on a free-draining volcanic parent material soil which received either 0 (control) or 100 kg N ha?1 as FDE or manure (about 2 and 15 % of dry matter (DM) contents in FDE or manure, respectively) with or without NBTPT (0.25 g NBTPT kg?1 effluent N). The experiment was conducted in the spring of 2012 and summer and autumn of 2013.Results and discussion
Results showed that application of manure and FDE, both in fresh and stored forms, potentially led to NH3 volatilization, ranging from 0.6 to 19 % of applied N. Difference in NH3 losses depended on the season and effluent type. Higher NH3 volatilization was observed from both fresh and stored manure, compared to fresh and stored FDE. The difference was mainly due to solid contents. The losses of NH3 were closely related to NH4 +-N content in the two types of manure. However, there was no relationship between NH3 losses and NH4 +-N content in either type of FDE. There was no consistent seasonal pattern, although lower NH3 losses from fresh FDE and stored FDE applied in spring compared to summer were observed. Potential NH3 losses from application of fresh FDE or manure were significantly (P?<?0.05) reduced by 27 to 58 % when NBTPT was added, but the UI did not significantly reduce potential NH3 volatilization from stored FDE or manure.Conclusions
This study demonstrated that NH3 losses from application of FDE were lower than from manure and that UIs can be effective in mitigating NH3 emissions from land application of fresh FDE and manure. Additionally, reducing the application of FDE in summer can also potentially reduce NH3 volatilization from pasture soil. 相似文献188.
Christensen PR Ruff SW Fergason RL Knudson AT Anwar S Arvidson RE Bandfield JL Blaney DL Budney C Calvin WM Glotch TD Golombek MP Gorelick N Graff TG Hamilton VE Hayes A Johnson JR McSween HY Mehall GL Mehall LK Moersch JE Morris RV Rogers AD Smith MD Squyres SW Wolff MJ Wyatt MB 《Science (New York, N.Y.)》2004,305(5685):837-842
The Miniature Thermal Emission Spectrometer (Mini-TES) on Spirit has studied the mineralogy and thermophysical properties at Gusev crater. Undisturbed soil spectra show evidence for minor carbonates and bound water. Rocks are olivinerich basalts with varying degrees of dust and other coatings. Dark-toned soils observed on disturbed surfaces may be derived from rocks and have derived mineralogy (+/-5 to 10%) of 45% pyroxene (20% Ca-rich pyroxene and 25% pigeonite), 40% sodic to intermediate plagioclase, and 15% olivine (forsterite 45% +/-5 to 10). Two spectrally distinct coatings are observed on rocks, a possible indicator of the interaction of water, rock, and airfall dust. Diurnal temperature data indicate particle sizes from 40 to 80 microm in hollows to approximately 0.5 to 3 mm in soils. 相似文献
189.
新城疫病毒西藏分离株的生物学特性鉴定及遗传进化分析 总被引:1,自引:0,他引:1
从西藏病死藏鸡中分离到具有血凝活性的病毒、经血凝抑制试验、电镜观察、PCR扩增和测序鉴定为新城疫病病毒(NDV),通过动物致病性试验证明该病毒对鸡具有致病性;分离毒株毒力测定结果显示,MDT为120h,EID50为10-8.44、IVPI为0.5、ICPI为0.6,均符合NDV弱毒株特征。血凝解脱及血凝素热稳定性试验显示:各分离株的血凝解脱时间短,血凝素热稳定性较差,符合NDV弱毒株的特征。F基因的序列测定遗传进化分析表明,西藏分离毒株之间的核苷酸序列具有99%的同源性,与疫苗株LaSota的同源性为90%;与国内标准强毒株F48E8同源性为81%。推导其氨基酸序列分析表明,各分离株的F蛋白的裂解位点氨基酸112 G-K-Q-G-R-L117,具有NDV弱毒株特征,与毒力测定结果相符。本研究首次报道了NDV西藏分离毒株遗传进化情况和生物学特性情况,为进一步研究高海拔、缺氧环境下NDV生物学特性变化研究奠定了基础。 相似文献
190.
为查明达坂城山区地衣物种多样性及其分布特征,在研究区不同海拔设置样地,开展了野外调查和室内鉴定分析。结果表明,达坂城山区地衣共有68种,隶属11目23科38属。其中,茶渍目、微孢衣目和黄枝衣目包含45个种(66.18%),占优势地位。地衣种类组成优势科、优势属和单属科、单种属情况明显,表现出达坂城山区地衣区系的特殊性和单一性。达坂城山区地衣主要由岩面生和地面生地衣种类组成,岩面生地衣占总种数的72.06%,地面生地衣占总种数的27.94%。壳状地衣在研究区占绝对优势,其次是叶状地衣和鳞片状地衣。该地区地衣共生藻类型主要为共球藻和球形绿藻,适应该地区干旱的生境条件。该地区地衣的分布具有垂直地带性特征,山地草原带的地衣种类最多,共47种,占总种数的69.12%;亚高山草甸带27种,占总种数的39.71%;高山草甸带25种,占总种数的36.76%。 相似文献