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71.
广东三岭山森林公园主要人工林碳汇功能及其经济价值评价 总被引:1,自引:0,他引:1
本文以广东三岭山森林公园的马尾松、尾叶桉、大叶相思人工林为研究对象,研究对比它们的碳储量和碳汇经济价值,为评价广东的3个优势造林树种的碳汇能力及为广东的造林选择提供依据。结果表明:3种人工林树种单位碳储量由大到小排列次序为:尾叶桉(166.89 t·hm-2)>大叶相思(128.72 t·hm-2)>马尾松(70.12 t·hm-2)。3种人工林平均碳汇经济价值按大小排列次序为:尾叶桉(45611.04元·hm-2)>大叶相思(35179.18元·hm-2)>马尾松(19163.80元·hm-2)。尾叶桉是这3种人工林中碳储量的主要部分,对广东三岭森林公园发挥着巨大的碳汇功能并具有强大的碳汇经济价值。因此,可以考虑在广东省碳汇造林时选择尾叶桉种植。 相似文献
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Impact of sampling and storage technique,and duration of storage,on the composition of fresh grass when analysed using near‐infrared reflectance spectroscopy 下载免费PDF全文
The objective of this study was to examine the effect of sampling technique (pluck or cut), storage duration (immediate analysis, 24‐h or 48‐h), storage temperature (ambient or chilled) and storage conditions (air present, air excluded or breathable) on the composition of fresh grass sampled from a sward managed to simulate grazing. Treatments were repeated across four sampling dates, with grass samples stored in grip seal bags prior to analysis using near‐infrared reflectance spectroscopy. Grass sampled by ‘pluck’ had a higher crude protein and ME content, and a lower acid detergent fibre (ADF) content, compared to that sampled by ‘cut’. Grass stored for 48 h had a lower water soluble carbohydrate (WSC) and ME content and a higher ADF content than for immediate analysis. Samples stored for 24 h did not differ from immediate analysis. Grass stored at ambient temperature had a lower WSC and ME content compared to immediate analysis. Grass stored under ‘breathable’ conditions had a lower ME content and higher ADF content than immediate analysis or samples stored with air present or air excluded. It is recommended that grass for analysis should be sampled by cutting, stored chilled (4°C) in a sealed bag to minimize exposure to oxygen and analysed within 24 h of harvest. 相似文献
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Peatlands are highly valued for their range of ecosystem services, including distinctive biodiversity, agricultural uses, recreational amenities, water provision, river flow regulation and their capacity to store carbon. There have been a range of estimates of carbon stored in peatlands in the United Kingdom, but uncertainties remain, in particular with regard to depth and bulk density of peat. In addition, very few studies consider the full profile with depth in carbon auditing. The importance of sub‐peat soils within peatland carbon stores has been recognized, but remains poorly understood and is included rarely within peatland carbon audits. This study examines the importance of the carbon store based on a study of blanket peat on Dartmoor, UK, by estimating peat depths in a 4 × 1 km survey area using ground penetrating radar (GPR), extraction of 43 cores across a range of peat depth, and estimation of carbon densities based on measures of loss‐on‐ignition and bulk density. Comparison of GPR estimates of peat depth with core depths shows excellent agreement, to provide the basis for a detailed understanding of the distribution of peat depths within the survey area. Carbon densities of the sub‐peat soils are on average 78 and 53 kg C/m3 for the overlying blanket peat. There is considerable spatial variability in the estimates of total carbon from each core across the survey area, with values ranging between 56.5 kg C/m2 (1.01 m total depth of peat and soil) and 524 kg C/m2 (6.63 m total depth). Sub‐peat soil carbon represents between 4 and 28 per cent (mean 13.5) of the total carbon stored, with greater values for shallower peat. The results indicate a significant and previously unaccounted store of carbon within blanket peat regions which should be included in future calculations of overall carbon storage. It is argued that this store needs to be considered in carbon audits. 相似文献
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以新疆赛买提杏为试验原料,选用0.9 mg/L的24-表油菜素内酯(24-epibrassionolide,EBR)对杏果实进行10 min的浸泡处理,将处理后的果实取出晾干后贮藏在温度为4℃、相对湿度(RH)90%~95%的冷库中,以蒸馏水处理为对照,定期测定相关指标,研究24-表油菜素内酯处理对杏果实贮藏品质的影响。结果表明,24-表油菜素内酯处理可以延缓杏果实贮藏期间可溶性固形物、可滴定酸、叶绿素和抗坏血酸含量的下降,有效降低杏果实的自然发病率,并能有效延缓呼吸速率和失重率的上升。 相似文献
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为研究不同贮藏方式对鲜食核桃在贮藏过程中品质的影响,以“清香”核桃鲜果为试材,分别采用青果贮藏((0±1) ℃、相对湿度70%~80%)、去青皮的湿果贮藏((-7±1) ℃、相对湿度70%~80%)及湿果真空贮藏((-7±1) ℃、相对湿度70%~80%)3种方式贮藏,每15 d对其品质指标进行观察测定。结果表明:随着贮藏时间的延长,所有贮藏方式处理的鲜食核桃的感官品质和营养成分均呈一定的下降趋势。其中,青果贮藏能较好地保持核仁的含水量,维持粗脂肪、蛋白质及可溶性糖含量的稳定性,贮藏后种皮色泽较好,核仁容易剥皮、风味较好,但果壳容易产生霉变;湿果贮藏和湿果真空贮藏可以减轻鲜核桃的霉变,延长了鲜核桃贮藏期,但随着贮藏时间的延长,湿果贮藏核仁水分散失较快,粗脂肪、蛋白质及可溶性糖含量变化较大,使得种皮色泽降低,核仁剥皮困难、风味下降。 相似文献
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