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江西金盆山林区天然常绿阔叶林生态系统碳储量研究 总被引:1,自引:0,他引:1
【目的】探讨亚热带典型天然常绿阔叶林碳储量及其碳分布格局,以期为常绿阔叶林生态系统碳汇功能评价提供基础数据和理论依据。【方法】以江西省金盆山林区优势树种生态系统生物量研究为基础,结合主要优势树种碳含量实测数据,对金盆山典型常绿阔叶林丝栗栲林、南岭栲林、米槠林的碳储量及碳空间分布格局进行研究,并以这3种林分的碳密度均值计算整个金盆山林区天然常绿阔叶林总碳储量。【结果】金盆山林区丝栗栲林、南岭栲林、米槠林生态系统碳密度分别为294.82、307.63、318.97 t/hm^2,林区生态系统总碳密度为307.14 t/hm^2,林区现存碳总量为2.25×10^6 t;生态系统碳密度分布规律为植被层>土壤层>凋落物层,植被层碳密度分布规律为乔木层>灌木层>草本层,其中乔木层主干的碳密度占56.54%;土壤层碳密度随着土壤层的加深呈下降趋势,40 cm以下土层间的碳密度变化不明显。【结论】金盆山林区常绿阔叶林不同林分间生态系统碳密度差异不显著,生态系统内碳密度有较强的空间分布规律,生态系统碳密度高于我国森林生态系统平均碳密度和多种典型森林类型碳密度,具有较强的碳汇功能。 相似文献
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围绕武夷山群落结构特征、主要生态功能以及与其他区域常绿阔叶林的比较进行研究表明:①对武夷山常绿阔叶林的群落特征调查主要集中在米槠林、甜槠林、丝栗栲林、青冈林和木荷林等5种森林群落类型,其中关于甜槠林群落结构特征的报道较多;②有关武夷山常绿阔叶林生态功能的研究主要集中在土壤特征和群落特征调查方面,在土壤特征调查方面主要研究了土壤的生化和理化性质,在群落调查方面主要回答了物种组成、多样性分析、种间联结性、生物量等问题,土壤和群落特征调查方面发表的文献占文献总数量的90%以上,而气候和水文方面的报道较少。 相似文献
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亚热带常绿阔叶林结构、树种多样性和土壤特性的研究(英文) 总被引:1,自引:0,他引:1
采用样地调查法,对日本冲绳岛北部的亚热带常绿阔叶林的林分结构,树种组成以及土壤特性等进行了调查分析。结果表明,该亚热带林具有林冠低矮、小径木多等特点。林分的平均林冠高度仅10m,平均立木密度达5400株·hm2(≥3.0cmDBH),其中胸径小于10cm的立木占64%。林分胸高断面积为54.4m2·hm-2。30个调查样地共出现树种数(≥3.0cmDBH)达80种,分属31个科。根据树种的重要值,Castanopsis sieboldii和Schima wallichii分别为优势树种和亚优势树种。树种多样性指数(H’)平均达3.63,均衡度指数(J’)为0.71,丰富度指数(S’)为4.72。这些多样性指数都随着优势树种重要值的增加而显著降低。土壤养分测定结果表明,该森林的土壤肥力低,异质性大,并可能存在Al毒害。由相关分析知,林分密度和优势树高均与土壤pH值呈显著正相关关系;多样性指数则与土壤交换性K ,Ca2 以及Ca2 /Al3 比呈显著的正相关,而与土壤有机碳,全氮和磷呈显著的负相关。这些结果说明土壤性质是影响冲绳亚热带常绿阔叶林林分结构和树种组成多样性的重要因素。图3表4参38。 相似文献
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采用地统计学的方法分析了蛟河阔叶红松林土壤氮素的空间分布特征,并利用克里格差值绘制了土壤有效氮和全氮的空间分布图,结果表明:有效氮的平均含量为0.95±0.45 g·L-1,A层土壤有效氮的平均含量为1.19±0.45 g·L-1,B层土壤有效氮的平均含量为0.87±0.43 g·L-1,C层土壤有效氮的平均含量为0.67±0.28 g·L-1,变异系数分别为0.469、0.374、0.481、0.424;全氮的平均含量为0.97±0.449 g·L-1,A层土壤全氮的平均含量为1.31±0.391 g·L-1,B层土壤全氮的平均含量为0.87±0.345 g·L-1,C层土壤全氮的平均含量为0.58±0.253 g·L-1,变异系数分别为0.463、0.298、0.397、0.437。土壤中有效氮和全氮的含量,在水平方向上波动较大,呈非正态分布;在垂直方向上逐层递减,A层B层C层。 相似文献
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以植被不同恢复阶段的普洱季风常绿阔叶林林地土壤为研究对象,分析了土壤理化性质随植被恢复的动态变化。结果表明:土壤容重随恢复时间的延长呈现降低的趋势,而土壤孔隙度和水分含量则随恢复时间的延长缓慢增大。土壤有机质和全N含量在恢复15年及原始林中最高,全P含量为恢复30年最低,原始林最高,全K含量则是恢复40年样地中最高。不同恢复阶段样地中,原始林中速效N含量最高,恢复15年样地中速效P含量最高,恢复40年样地中速效K含量最高。所有恢复阶段间pH值均无显著性差异,而阳离子交换量由高到低依次为恢复15年>原始林>恢复40年>恢复30年。土壤理化性质相关性分析显示,土壤容重与土壤全N、土壤全P、速效N、有机质具有显著相关性,而土壤孔隙度则仅与土壤pH值具有显著相关性,土壤水分含量则与土壤全N、速效N、阳离子交换量具有显著相关性。 相似文献
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This study explores the sprouting characteristics of an evergreen broad-leaved forest after clear-cutting based on a survey
of 1,893 stumps of 62 tree species in Okinawa, Japan. The sprouting capabilities of the stumps varied among tree species.
The stumps of 60 species could produce sprouts, while those of the other two species could not. In 10 of the sprouting species,
the mean sprout-stem number was higher than 4.0 stems per stump; nine sprouting species showed low sprouting capabilities.
Additionally, Castanopsis sieboldii and Schima wallichii, the dominant species, exhibited high sprouting capabilities. Further, the sprouting capabilities varied with stump diameter
at breast height (DBH). Stumps with a larger DBH tended to have a higher mean number of sprout stems per stump, higher DBH,
and higher tree height than the smaller stumps. The forest stands regenerated by sprouting might recover into a tree community
similar to that before clear-cutting. 相似文献
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不同采伐强度对闽西常绿阔叶林林分结构稳定性的影响 总被引:3,自引:0,他引:3
应用多样性分析方法和改进后的 M.Godron 稳定性测定方法研究常绿阔叶林5种不同强度采伐(弱度9.8%、中度24.5%,强度46.8%和极强度72.3%和皆伐)作业10 a后林分结构稳定性.结果表明,择伐林地林分处于稳定状态,随着择伐强度的增强,林分的稳定性开始逐渐降低.皆伐林地林分处于不稳定状态.对于常绿阔叶林的科学经营,从稳定性出发,应尽量采取择伐方式,尤其是中低强度的择伐方式. 相似文献
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Xiaoniu Xu Yoshihiro Tokashiki Eiji Hirata Tsutomu Enoki Kangoro Nogami 《Journal of Forest Research》2000,5(3):151-156
Patterns of litterfall and nutrient input in a subtropical evergreen broad-leaved forest in northern Okinawa, Japan, were
studied during May, 1996–April, 1999. The mean annual rate of litterfall in the five sampling plots ranged from 6.84 to 8.93
Mg ha−1 yr−1, of which 63.3–68.5% were leaves; 22.4–29.1% woody parts (including branches < 5.0 cm in diameter and bark); 2.8–5.0% sexual
organs and 4.6–6.3% miscellaneous material. Significant differences were found among plots and among years. Significantly
monthly differences pronounced seasonal patterns in litterfall were observed. Total litterfall and leaf litter showed negative
correlations with relative basal area of the dominant species,Castanopsis sieboldii; and showed positive correlations with mean height of the stands. The dominant species,C. sieboldii produced an average of 2.36 Mg ha−1 yr−1 of leaf litter, which covered 30.5% of the annual litter production, and the nutrient input from those litterfall contributed
32.3, 28.3, 30.2, 22.2, 32.5, and 30.5% of total N, P, K, Ca, Mg, and Na, respectively. Nutrient use efficiency in litter
production was high, especially for P and K compared with other broad-leaved forests in Japan indicating that P and K may
be limiting in Okinawan evergreen broad-leaved forest. 相似文献
12.
青冈栎次生林作为亚热带地区次生林的典型代表之一,研究其林分内主要树种的空间分布格局及关联性,可以更好地开展次生林经营指导工作。通过对9块青冈栎次生林样地的调查,运用空间点格局分析方法对其林分内主要树种的空间分布格局及种间关联性进行研究。结果表明:1)以完全空间随机模型为零假设时,林分整体的空间分布格局在0~12m尺度上呈聚集分布,在12~25m尺度呈随机分布,大于25m尺度趋于均匀分布态势;以异质泊松模型为零假设时,林分整体的空间分布格局总体上呈随机分布;2)样地内青冈栎、杜鹃和拟赤杨在小尺度上呈聚集分布,随尺度增加呈随机分布或均匀分布;甜槠、杉木和檵木基本在所有尺度呈随机分布。3)样地内建群种青冈栎与杉木在所有尺度呈负相关,与其它主要树种在小尺度呈负相关,随着尺度增加变为不相关;所有伴生树种的种间关联性在0~2m为负相关,在其它尺度上不相关为主。青冈栎次生林的空间分布格局受生境异质性的影响,且空间分布格局和主要树种间的关联性随空间尺度的不同而变化。 相似文献
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光皮桦与青冈栎苗期生理生化特性研究 总被引:2,自引:0,他引:2
对光皮桦和青冈栎幼苗进行硝酸还原酶活力、氨基态氮含量及全氮含量测定,结果显示光皮桦的三项生理生化指标均明显高于青冈栎。硝酸还原酶活力在光皮桦各营养器官中的分布大小是叶>根>茎;在青冈栎各器官的分布是叶最高,茎其次,根最低。氨基态氮含量在两树种的分布情况与硝酸还原酶活力类似。生长盛期的硝酸还原酶活力及氨基态氮含量达到高峰。研究表明光皮桦的氮素同化能力和贮藏能力高于青冈栎,因此营养生长旺盛。 相似文献
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Gong Zhang Guang-Ming Zeng Guo-He Huang Yi-Min Jiang Jia-Mei Yao Chun-Yan Du Ru Jiang Chang Zhang 《Journal of Forest Research》2006,11(6):389-396
The effects of dry deposition, canopy leaching, precipitation ion concentration, and precipitation H+ concentration on net throughfall flux (NTF, throughfall minus bulk precipitation) were evaluated on a seasonal basis by using
a multiple regression analysis approach based on an observation period of 4 years in Shaoshan subtropical mixed evergreen
forest, south-central China. Regression analysis results indicated that the estimated canopy exchange flux was the dominant
factor regulating the NTF and the calculated dry deposition was a minor term. The seasonal dry deposition of base cations
accounted for 15%–43% of the NTF. The NTF analysis showed that K+, Ca2+, Mg2+, Na+, and weak acids in throughfall were derived from foliar leaching and the canopy uptakes of H+, NH4
+, and NO3
− were from precipitation. The retention rate of proton (H+ and NH4
+) in the canopy was close to the canopy leaching rate of base cations when corrected for weak acids because weak acid-induced
canopy leaching did not exchange with protons, which suggested that the canopy leaching processes neutralized acid precipitation
in Shaoshan forest. 相似文献
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Dynamics of nitrogen nutrition of coexisting dominant trees in mixed broad-leaved/Korean pine forest 总被引:1,自引:0,他引:1
IntroductionThecapacityofwoodyplantstoassimilateavail-ablenitrogen(nitrateandammonium)hasbeenweIlstudied,especiaIIyintermsofhabitatandspe-cies-reIateddifferencesinnitrateandammoniumassimiIationcapacity(Addoms1937lHauck1968lAlGharbietaI.1984,L8eetaI.1978,Tamm,1991,Vi-touseketaI.,1982iLietaI1994a,1994b,1995)However,nostudyhasfocusedonspecies-specifictemporalvariationinnitrateandammoniumassimiIa-tionamongexplicitIyco-existingwoodyplants,eventhoughtemporaIdifferentiationintheuseofnitratean… 相似文献
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Biomass,and carbon and nitrogen pools in a subtropical evergreen broad-leaved forest in eastern China 总被引:1,自引:0,他引:1
Subtropical evergreen broad-leaved forest is the most widely distributed land-cover type in eastern China. As the rate of
land-use change accelerates worldwide, it is becoming increasingly important to quantify ecosystem biomass and carbon (C)
and nitrogen (N) pools. Above and below-ground biomass and ecosystem pools of N and C in a subtropical secondary forest were
investigated at Laoshan Mountain Natural Reserve, eastern China. Total biomass was 142.9 Mg ha−1 for a young stand (18 years) and 421.9 Mg ha−1 for a premature stand (ca. 60 years); of this, root biomass was from 26.9 (18.8% of the total) to 100.3 Mg ha−1 (23.8%). Total biomass C and N pools were, respectively, 71.4 Mg ha−1 and 641.6 kg ha−1 in the young stand, and 217.0 Mg ha−1 and 1387.4 kg ha−1 in the premature stand. The tree layer comprised 91.8 and 89.4% of the total biomass C and N pools in the young stand, and
98.0 and 95.6% in the premature stand. Total ecosystem C and N pools were, respectively, 101.4 and 4.6 Mg ha−1 for the young stand, and 260.2 and 6.6 Mg ha−1 for the premature stand. Soil C comprised 23.8–29.6% of total ecosystem C whereas soil N comprised 76.9–84.4% of the total.
Our results suggest that a very high percentage of N in this subtropical forest ecosystem is stored in the mineral soil, whereas
the proportion of organic C in the soil pool is more variable. The subtropical forest in eastern China seems to rapidly accumulate
biomass during secondary succession, which makes it a potentially rapid accumulator of, and large sink for, atmospheric C. 相似文献
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Soluble organic nitrogen in forest soils of northeast China 总被引:2,自引:0,他引:2
Soluble organic nitrogen (SON) is recognized as a sensitive indicator of soil nitrogen status. The present work was conducted in the temperate forests of northeast China where soils are typically characterized by high organic matter and high organic nitrogen content, and soil sampling was made in early spring just after the freeze-thaw period. The water extracted SON pools in the organic layer of forest soils were measured within the range from 156.0 mg·kg-1 to 292.6 mg·kg-1, a similar magnitude of salt solution extracted SON pools reported in literatures. However, the water soluble SON pools in 0-15 cm mineral soils in present study were much higher (3-10 times) than any other reports, ranging from 58.6 mg·kg-1 to 125.2 mg·kg-1. Water soluble SON varied markedly among the soils under different forests and at different sites. The SON in water extracts were positively and significantly correlated to soil organic matter and total nitrogen contents, but negatively correlated to microbial biomass nitrogen (MBN). The reasons of the abnormally large SON pools and the negative correlations between SON and MBN in the 0-15cm mineral soils in this study were specially discussed. 相似文献
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为全面掌握龙王山自然保护区落叶阔叶林的林分结构特征,设置了3个100m×100m样地,对其中的6个30m×30m样方,进行群落和林分调查。经统计分析,结果表明龙王山落叶阔叶林中树种种类多,优势树种为小叶白辛树和锐齿槲栎,林分树种组成具有一定的复杂性和多样性。林分株数密度平均为1511株/hm2,林分样地间差异不明显。胸径分布呈典型的倒"J"型;树高主要集中在4-9m的树高级,分布则呈偏左的正态分布。林分结构总体上具有多树种复层异龄的基本特征,具有良好的生物多样性保护和植物种质资源保存作用。 相似文献
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Soil nitrogen status of larch plantations in comparison with secondary broad-leaved forest 总被引:3,自引:0,他引:3
IntroductionSoildegradationofsouthernChinesefir(CunnhaamialanceolaIe)pIantationshavebeenCon-tinuaIlyreiorted(ShenWeitongl992;Che11BingI1aol992;FangQil992).lnthenortI1eastforestregionsofChina,larch(LarirohensisandLa)`ixgInelinii)planta-tionsmade7opercentoftheman-madeforests,andthechangesinsoilpropertiesundertI1econiferouspIanta-tionshavealsodrawnmuchattentionofmanyforesters.OurobjectivewastoexaminethedifferenceinsoilnitrogenstatusbetweenLarchp1antatiol1sandsecon-darybroad-Ieavedforests(… 相似文献
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Ho-Taek Park Shigeaki Hattori Takafumi Tanaka Gyung-Soo Cha 《Journal of Forest Research》1999,4(4):261-269
This study was conducted to document the effects of canopy change on radiation and energy balances in a deciduous broad-leaved
forest. Global solar radiation was highly variable with a maximum close to 28.7 MJ m−2 day−1 and a minimum of about 0.7 MJ m−2 day−1. The high daily variation of net radiation was the result of the frequency and duration of rainfall. The mean annual albedo
in this study site was 0.126. Seasonal variation of albedo was characterized by steadily decreasing values with leaf-fall,
but at the time when new leaves sprouted the trend did turn upwards. The mean annual radiation efficiency at this study site
was 0.564, and the seasonal variation of the radiation efficiency was dependent upon the net long-wave radiation rather than
albedo. This study also illustrated the seasonal variation of the proportion of the actual evaporation to the equilibrium
evaporation as a means for estimating the latent heat flux from forest using the equilibrium evaporation model. Seasonal variation
of the proportion of the actual evaporation to the equilibrium evaporation reflected the physiological and productive activities
of trees. Latent heat flux dominated the energy balance and, in particular, reached about 96% of net radiation in July. 相似文献