豫西北地区暖性灌草丛类草地生态系统固碳特征

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李琳, 赵威. 豫西北地区暖性灌草丛类草地生态系统固碳特征. 草业学报, 2019,28(5): 26-35
LI Lin, ZHAO Wei. Carbon sequestration characteristics of a warm shrub tussock grassland ecosystem in northwestern Henan. Acta Prataculturae Sinica,2019,28(5): 26-35 复制到剪切板

Doi:10.11686/cyxb2018309
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豫西北地区暖性灌草丛类草地生态系统固碳特征

李琳, 赵威^*

河南科技大学农学院,河南洛阳471023

*通信作者. E-mail: zhaowei1@haust.edu.cn

作者简介:李琳(1994-),女,河南济源人,在读硕士。E-mail: 345660744@qq.com

收稿日期: 2018-05-10

基金项目:NSFC-河南人才培养联合基金(U1304306),中国科学院战略性先导科技专项-应对气候变化的碳收支认证及相关问题(XDA05050402)和河南科技大学学科提升计划(13660001)资助

摘要

草地中灌木数量动态变化是影响草地生态系统碳收支的重要因素,灌木层的碳储量是草地生态系统碳库中最不确定的组分之一。暖性灌草丛在豫西北丘陵山地广泛分布,属区域典型植被类型。为揭示暖性灌草丛类草地生态系统固碳特征,对豫西北地区7个样地的灌木层、草本层与土壤碳密度进行了调查,并对生态系统碳密度进行了计算。结果表明,植被与土壤平均有机碳密度分别为2360.07和4610.47 g C·m^-2,其中灌木层植被碳密度(981.63 g C·m^-2)低于草本层(1387.44 g C·m^-2),但差异不显著( P>0.05)。植被碳密度主要由根系所贡献,占整个植被碳密度的93.04%,其中灌木层根系所占比例为41.51%,略小于草本层。生态系统中土壤碳密度占有较大比例,约占整个生态系统碳密度的62.80%。对不同样地而言,由于各自所处生境不同,其生态系统固碳特征存在一定区域差异。各样地的植被碳密度大小顺序依次为P₁>P₅>P₂>P₄>P₆>P₇>P₃,但差异并不显著( P>0.05);土壤碳密度大小顺序依次为P₁>P₂>P₆>P₅>P₄>P₃>P₇,其中P₁与P₄、P₃、P₇存在显著差异( P<0.05);生态系统碳密度大小顺序依次为:P₁>P₂>P₆>P₅>P₄>P₇>P₃,其中P₁与P₄、P₃、P₇差异显著( P<0.05)。

关键词: 灌草丛草地; 生物量分布; 碳密度; 豫西北

Carbon sequestration characteristics of a warm shrub tussock grassland ecosystem in northwestern Henan

LI Lin, ZHAO Wei^*

College of Agriculture, Henan University of Science and Technology, Luoyang 471023, China

*Corresponding author. E-mail: zhaowei1@haust.edu.cn

Abstract

Dynamics of shrub populations are important factors affecting the carbon budget of natural grassland ecosystems. Shrub biomass and the soil carbon stock beneath shrubs are among the most uncertain components in grassland ecosystem carbon accounting. Warm shrub tussock is widely distributed in hilly areas in northwestern Henan and comprises a ‘typical’ (i.e. reference) regional vegetation type. To elucidate the carbon sequestration characteristics of a warm shrub tussock grassland ecosystem, the carbon density of above ground shrub and herb biomass, and the associated soil carbon density were measured in seven plots of different areas in northwestern Henan, and ecosystem carbon density was calculated. The mean vegetation and mean soil organic carbon densities were 2360.07 and 4610.47 g C·m^-2, respectively. The vegetation carbon density for shrub vegetation was 981.63 g C·m^-2, while that of the herb layer was 1387.44 g C·m^-2. The carbon density was mainly contributed by the roots, which accounted for 93.04% of the total vegetation biomass. For shrubs, the root biomass was 41.51%, of total biomass; for herbs it was slightly more. The soil carbon density accounted for 62.80% of the total ecosystem carbon density. Across the seven plots measured, there were differences in the characteristics of ecosystem carbon sequestration. For vegetation carbon density, the plots ranked: P₁>P₅>P₂>P₄>P₆>P₇>P₃, but the difference was not significant ( P>0.05). For soil carbon density the ranking was P₁>P₂>P₆>P₅>P₄>P₃>P₇, with significant differences between P₁ and P₄, P₃, and P₇ ( P<0.05). The ranking for ecosystem carbon density was P₁>P₂>P₆>P₅>P₄>P₇>P₃, with P₁ being significantly different from P₄, P₃ and P₇ ( P<0.05).

Keyword: shrub tussock grassland; biomass distribution; carbon density; northwest Henan

文章图片

大气中温室气体逐年增加导致全球变暖日益严重, 受到了越来越多国际学者的关注^[1]。陆地生态系统碳库主要由植被和土壤两部分构成, 二者总储量约为大气碳库的3倍, 对气候变化和生态系统碳循环具有重要影响^{[2, 3]}。近年来, 我国学者开展了大量有关森林和草地生态系统植被碳储量估算的研究^{[4, 5, 6]}, 但目前对于灌丛生态系统植被生产力与碳储量研究相对缺乏, 尤其缺少地下根系和凋落物的数据^[7], 导致对碳储量的估算具有极大的不确定性。灌草丛多为森林破坏后形成的次生植被, 广泛分布于我国温带地区的丘陵山地, 是一种以灌木为优势种、中生和旱中生草本为建群种的主要植被类型^[8]。灌木具有种类繁多、生命力强、生产力高、适生范围宽等特点, 不仅在群落演替过程中扮演重要角色, 在全球碳循环和气候调节中也发挥着重要作用^{[1, 9]}。全球气候变暖以及人为干扰影响使得草地灌丛化日益严重^{[10, 11]}, 以及生物入侵引发的区域碳储量变化, 使得灌草丛固碳潜力研究成为新的研究热点^{[12, 13]}, 而灌草丛面积增加被认为是陆地生态系统碳储量增加的主要原因^[14]。但对于灌草丛的研究主要集中在其地上部分^{[9, 15]}, 有关地下生物量研究较少。灌丛生物量的估算多采用转换因子法^[9], 缺乏实测数据, 导致估算结果与实测值相差较大。我国是世界上灌草丛分布面积最广泛的国家之一, 拥有灌草丛近2.0× 10⁸ h ${m^{2}}^{[16]}$ , 占我国陆地面积的1/5, 是全球现存森林面积的近2倍^[9]。因此研究灌草丛面积增加而导致的生态系统碳储量改变, 对于正确评价我国陆地生态系统的碳汇功能和固碳潜力具有重要意义。

河南气候温和, 雨量充沛, 拥有各类草地面积约4.60× 10⁶ hm², 占全省土地面积的27.54%, 占全国草地的1.20%。作为河南典型草地类型之一, 暖性灌草丛主要分布在半干旱半湿润的豫西北地区。由于林地砍伐、土地弃耕等人类活动影响, 豫西北灌草丛分布广泛, 其碳储量占植被很大比例。本研究在豫西北暖性灌草丛草地进行调查取样, 分析不同样地固碳特征, 并比较草本层与灌木层的碳储量差异, 以期为准确评估我国草地生态系统总体碳库及其固碳潜力提供基础数据。

1 材料与方法

1.1 研究区概况

豫西北地区位于河南境内伏牛山脊和淮河干流的秦岭淮河一线以北, 属暖温带、湿润至半湿润季风气候^[17], 四季分明, 年平均气温10.913.73 ℃, 年平均降水量528.52857.22 mm^[18]。暖性灌草丛集中分布在豫西北地区, 地形多丘陵山地, 主要土壤类型有钙质石质土、石质土、棕壤性土、褐土、黄绵土等。主要的灌木优势种为酸枣(Ziziphus jujuba)、黄荆(Vitex negundo)、杠柳(Periploca sepium)、长叶胡枝子(Lespedeza caraganae)等, 草本优势种为白羊草(Bothriochloa ischaemum)、阿拉伯黄背草(Themeda triandra)、马唐(Digitaria sanguinalis)等。

1.2 研究方法

1.2.1 样地选择在20世纪90年代全国草地类型图和2000土地利用图基础上, 结合1997-1998年郭孝等^{[19, 20]}对河南草地的调查结果, 选取豫西北地区暖性灌草丛草地, 于2017年开展调查研究。

1.2.2 样方分布及取样原则根据典型性和代表性原则设置7个样地(表1), 分别位于河南林州、辉县、灵宝、嵩县、淇县、渑池、修武, 每个样地14个取样点。在每个取样点中, 按照坡度方向设置一条100 m的样线, 每隔20 m设定12个5 m× 5 m的灌木样方, 同时在灌木样方内设置两个1 m× 1 m的草本植物样方, 调查灌木与草本植物种类及群落特征, 并进行植物与土壤的取样。

表1 样地概况 Table 1 Basic information of the sampled plots

样地 Plot	地理坐标 Location	海拔 Altitude (m)	植被盖度 Vegetation coverage (%)	土壤类型 Soil type	年降水量 Annual precipitation (mm)	年均温度 Mean average temperature (℃)	灌木物种组成 Composition of shrub species	草本优势种组成 Dominant species of herb
P₁	113.73° E, 36.05° N	471	65	钙质石质土 Calcareous stone soil	672.1	12.8	酸枣, 黄荆, 截叶铁扫帚, 野皂荚, 多花胡枝子Ziziphus jujube, Vitex negundo, Lespedeza cuneata, Gleditsia microphylla, Lespedeza floribunda	白羊草, 荩草, 阿拉伯黄背草, 马唐Bothriochloa ischaemum, Arthraxon hispidus, Themeda triandra, Digitaria sanguinalis
P₂	113.65° E, 35.80° N	564	81	石质土 Stony soil	489.1	13.5	黄荆, 酸枣, 茵陈蒿, 野皂荚, 椭圆叶木蓝, 杠柳, 中华绣线菊V. negundo, Z. jujube, Artemisia capillaries, G. microphylla, Indigofera cassoides, Periploca sepium, Spiraea chinensis	白羊草, 狗尾草, 阿拉伯黄背草, 马唐B. ischaemum, Setaria viridis, T. triandra, D. sanguinalis
P₃	114.68° E, 34.91° N	517	53	棕壤性土 Brown soil	606.5	14.5	铁杆蒿, 长叶胡枝子, 酸枣, 河北木蓝, 地稍瓜, 截叶铁扫帚, 紫穗槐Artemisia gmelinii, Lespedeza caraganae, Z. jujube, Indigofera bungeana, Cynanchum thesioides, L. cuneata, Amorpha fruticosa	白羊草, 野艾蒿, 荩草B. ischaemum, Artemisia lavandulaefolia, A. hispidus
P₄	112.72° E, 34.52° N	362	53	褐土性土 Cinnamon soil	681.5	14.2	黄荆, 杠柳, 多花胡枝子, 中华绣线菊, 两面针V. negundo, P. sepium, L. floribunda, S. chinensis, Zanthoxylum nitidum	白羊草, 阿拉伯黄背草, 荩草B. ischaemum, T. triandra, A.hispidus
P₅	114.05° E, 35.70° N	424	60	褐土、钙质石质土 Cinnamon soil, Calcareous stone soil	519.6	13.8	黄荆, 酸枣, 野皂荚, 中华绣线菊, 长叶胡枝子, 卵叶鼠李, 杭子梢V. negundo, Z. jujube, G. microphylla, S. chinensis, L. caraganae, Rhamnus bungeana, Campylotropis macrocarpa	白羊草, 荩草, 马唐B. ischaemum, A.hispidus, D. sanguinalis
P₆	111.96° E, 35.01° N	729	65	黄绵土 Loessial soil	662.4	12.6	陕西荚蒾, 黄栌, 多花胡枝子, 黄荆, 酸枣, 美丽胡枝子Viburnum schensianum, Cotinus coggygria, L. floribunda, V. negundo, Z. jujube, Lespedeza formosa	野艾蒿, 阿拉伯黄背草, 马唐A. lavandulaefolia, T. triandra, D. sanguinalis
P₇	113.38° E, 35.47° N	1234	76	棕壤性土 Brown soil	560.4	14.4	黄荆, 悬钩子, 地稍瓜, 多花胡枝子, 杠柳, 椭圆叶木蓝, 雀儿舌头V. negundo, Rubus coreanus, C. thesioides, L. floribunda, P. sepium, I. cassoides, Leptopus chinensis	白羊草, 阿拉伯黄背草, 荩草B. ischaemum, T. triandra, A. hispidus

表1 样地概况 Table 1 Basic information of the sampled plots

1.3 生物量的测定

采用收获法^[8]测定群落植物活体和凋落物生物量。草本植物地面以上的所有部分齐地面剪下, 灌木按照高度(height, H)大小确定剪取比例, 收集所有当年的新枝、老龄枝和叶片(H> 2.0 m, 取25%; H=1.02.0 m, 取50%; H< 1.0 m, 取100%)以及地上的凋落物, 除去土粒和杂质, 带回实验室于65 ℃下48 h烘干后称量。地下生物量草本层测定采用根钻法。在每个草本样方中用7.0 cm根钻取3钻后合并, 分成05 cm、510 cm、1020 cm、2030 cm、3050 cm、5070 cm、70100 cm共7个土层, 在0.125 mm筛中清洗干净, 放进65 ℃烘干至恒重。其他调查取样全部完成后, 对灌木样方内生长的所有灌木进行完整挖掘, 挖出的根系洗净后65 ℃烘干至恒重。土壤样品采集方法与草本层根系生物量相同, 分层装好后带回实验室置于室内阴凉处风干, 去除杂质研磨后过筛(0.200 mm)备用。

1.4 植被和土壤碳密度计算

1.4.1 植被有机碳含量测定和碳密度计算采用Carlo-Erba的NA1500元素分析仪测定地上植物活体、凋落物的有机碳含量, 结合各自生物量数据计算碳密度。

Cd=α × M

式中:Cd为碳密度(g C· m^-2); α 为有机碳含量(%); M为地上或地下生物量(g· m^-2)。

1.4.2 土壤有机碳含量测定和碳密度计算采用Carlo-Erba的NA1500元素分析仪测定土壤有机碳含量。根据土壤有机碳含量、土壤容重、土层深度等参数计算土壤有机碳密度(soil organic carbon density, SOC_density, g C· m^-2):

SOC_density= $\overset{n}{\sum_{i = 1}}$ D_i× θ _i× C_i× (1-δ _i)× 10

式中:n为土层数; D_i为不同土层厚度(cm); θ _i为土壤容重(g· cm^-3); C_i为不同土层土壤有机碳含量(%); δ _i为> 2 mm砾石含量(体积%)。

1.5 数据处理

采用Microsoft Excel 2013进行数据整理。采用SPSS 18.0软件One-way ANOVA模块进行单因素方差分析和Duncan多重比较(α =0.05)。采用OriginPro 18.0软件作图。

2 结果与分析

2.1 生物量及群落层组成

由表2可知, 豫西北地区不同样地暖性灌草丛灌木层的生物量大小顺序为:P₇> P₁> P₆> P₂> P₄> P₃> P₅, 数值介于1426.083193.47 g· m^-2, 平均为2231.41 g· m^-2, 但各样地间生物量差异并不显著(P> 0.05)。灌木层各器官生物量大小顺序为:根系> 老枝> 新枝> 叶片> 凋落物, 其中地下平均生物量为2076.37 g· m^-2, 地上平均生物量为155.02 g· m^-2。不同样地草本层生物量差异较大, 顺序依次为:P₅> P₄> P₁> P₂> P₆> P₃> P₇, 平均生物量为4261.01 g· m^-2, 其中P₅最大为7060.21 g· m^-2, P₇最小为2280.3 g· m^-2, 二者之间差异显著(P< 0.05)。草本层生物量大小顺序为:根系> 活体> 凋落物, 地下平均生物量为3889.52 g· m^-2, 地上平均生物量为271.49 g· m^-2, 其中地下生物量明显高于地上生物量。不同样地群落整体生物量大小顺序为:P₅> P₁> P₄> P₂> P₆> P₇> P₃, 平均生物量为6492.42 g· m^-2, 其中草本层生物量(65.63%)> 灌木层(34.37%)。

表2 各样地不同群落层生物量 Table 2 Biomass of community layers in each sampled plot (Mean± SE, g· m^-2)

2.2 地上碳密度

如图1所示, 各样地灌木层地上碳密度大小依次为:P₅> P₇> P₁> P₄> P₂> P₃> P₆, 平均碳密度为70.17 g C· m^-2, 其中P₅最大为102.43 g C· m^-2, P₆最小为44.54 g C· m^-2, 但二者差异并不显著(P> 0.05)。灌木层各器官平均碳密度大小顺序为:老龄枝> 叶片> 新枝> 凋落物, 其中老龄枝最高为30.12 g C· m^-2, 但不同器官碳密度各样地之间差异均不显著(P> 0.05)。各样地草本层地上碳密度大小依次为:P₂> P₆> P₄> P₁> P₃> P₇> P₅, 平均碳密度为103.01 g C· m^-2, 其中P₂最大为192.88 g C· m^-2, P₅最小为61.46 g C· m^-2, 二者之间差异显著(P< 0.05)。草本层活体碳密度大小顺序为:P₂> P₁> P₆> P₄> P₃> P₇> P₅, 平均碳密度为65.87 g C· m^-2, 但各样地间差异并不显著(P> 0.05)。凋落物碳密度大小依次为:P₂> P₄> P₆> P₁> P₅> P₃> P₇, 平均碳密度为37.13 g C· m^-2, 其中P₂最大为104.22 g C· m^-2, 显著大于其他6个样地(P< 0.05)。不同样地地上平均碳密度草本层> 灌木层, 但不同样地草本层地上碳密度差异显著(P< 0.05), 但灌木层差异不显著(P> 0.05)。

	Figure Option View Download New Window
	图1 各样地地上碳密度不同小写字母表示不同样地间差异显著(P< 0.05), 下同。Fig.1 Aboveground carbon density of each sampled plot Different lowercase letters indicated significant difference among different sampling sites at 0.05 level, the same below.

2.3 根系碳密度

由图2可知, 暖性灌草丛根系总碳密度为2195.88 g C· m^-2。其中灌木层根系碳密度大小顺序为:P₇> P₁> P₆> P₂> P₄> P₃> P₅, 平均碳密度为911.45 g C· m^-2, 占草地根系总碳密度的41.51%, 但7个样地间差异并不显著(P> 0.05)。草本层根系碳密度大小依次为:P₅> P₁> P₂> P₄> P₆> P₃> P₇, 平均碳密度为1284.43 g C· m^-2, 其中P₅最大为2192.66 g C· m^-2, P₇最小为469.82 g C· m^-2, 两者间差异显著(P< 0.05)。

	Figure Option View Download New Window
	图2 各样地根系碳密度Fig.2 Root carbon density of each sampled plot

2.4 植被与土壤碳密度

如图3所示, 暖性灌草丛植被碳密度为2360.07 g C· m^-2。其中灌木层植被碳密度大小依次为:P₇> P₁> P₆> P₂> P₄> P₃> P₅, 平均碳密度为981.63 g C· m^-2, 其中P₇最大为1428.25 g C· m^-2, P₅最小为630.65 g C· m^-2, 但样地间差异并不显著(P> 0.05)。草本层植被碳密度大小顺序为:P₅> P₂> P₁> P₄> P₆> P₃> P₇, 平均碳密度为1387.44 g C· m^-2, 其中P₅最大为2254.12 g C· m^-2, P₇最小为533.72 g C· m^-2, 二者之间差异显著(P< 0.05)。由以上结果可知, 不同样地植被碳主要分布于地下, 灌木层根系碳密度占植被碳密度的83.76%96.02%, 草本层根系碳密度占植被碳密度的88.02%97.27%。土壤是暖性灌草丛最主要的固碳场所。各样地土壤碳密度大小依次为:P₁> P₂> P₆> P₅> P₄> P₃> P₇, 平均碳密度为4610.47 g C· m^-2, 其中P₁最大为8426.29 g C· m^-2, P₇最小为1794.3 g C· m^-2, 二者之间差异显著(P< 0.05)。

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	图3 各样地植被与土壤碳密度Fig.3 Vegetation and soil carbon density of each sampled plot

2.5 生态系统碳密度

各样地生态系统碳密度大小顺序为:P₁> P₂> P₆> P₅> P₄> P₇> P₃, 生态系统平均碳密度为6979.54 g C· m^-2, 其中P₁最大为11349.89 g C· m^-2, P₃最小为3733.06 g C· m^-2, 二者之间差异显著(P< 0.05)(图4)。土壤层有机碳密度占生态系统的比例分别为P₁(74.24%)> P₆(73.38%)> P₂(70.8%)> P₅(62.21%)> P₃(58.61%)> P₄(52.56%)> P₇(47.77%)。草本层占生态系统碳密度的12.39%30.92%, 灌木层占生态系统碳密度的8.26%38.02%。暖性灌草丛生态系统碳密度空间分布序列为:土壤层> 植被层(灌木层+草本层), 而土壤碳密度是生态系统碳密度的最主要来源。

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	图4 各样地生态系统碳密度Fig.4 Ecosystem carbon density of each sampled plot

3 讨论

植被净初级生产力是陆地生态系统碳库的主要来源, 植被净初级生产力变化反映了生态系统对气候及土地利用变化的响应^[14]。灌草丛生态系统作为一个巨大的潜在碳汇, 在全球碳平衡和气候调节中发挥着重要作用^[21]。生物量动态变化是反应物质积累与生产潜力的重要指标, 也体现了植物的生长规律^[22]。而植物不同组分生物量分配不仅受外界环境限制, 同时还受植物遗传特性和个体差异影响^[23]。根据最优分配理论, 植物通过调节生物量在各器官中的分配来适应外界环境, 以最大限度获取资源, 从而维持最大生长速率^[24]。当光照受到限制时, 植物会分配更多资源在枝、叶; 而当水分和养分受限时, 更多资源会分配到地下根系^[25]。本研究中暖性灌草丛灌木层各器官生物量大小顺序为:根系> 老枝> 新枝> 叶片> 凋落物, 草本层生物量大小顺序为:根系> 活体> 凋落物, 无论是灌木层还是草本层, 其地下生物量均明显高于地上, 这是由于暖性灌草丛主要分布在豫西北地区, 降水较豫南地区少, 但光照充足。灌草丛生物量在群落不同层次之间的分配受群落特性和物种组成等因素的综合影响^[26]。已有的亚热带灌草丛生物量研究中, 生物量在植被层上的分配多表现为灌木层> 草本层> 凋落物层^[27], 本研究中将灌木层与草本层的凋落物进行分别计算, 更能准确估算灌木层和草本层各自的固碳量。研究结果表明, 灌木层生物量小于草本层, 主要原因是研究区草本物种丰富、种群密度大, 且黄背草等株型高大, 具有明显竞争优势, 相比而言灌木层则显得较为稀疏。在灌木层中, 老龄枝生物量普遍高于新生枝, 叶片生物量最低, 可见本地区灌木生物量主要分配在老龄枝中, 而新枝所占比重较小, 反映了灌木固碳缓慢, 这与杨昊天等^[28]的研究结果一致。此外灌木叶片所占比例最小, 也与研究地点普遍存在放牧等人为干扰, 导致其生物量降低有关^[29]。

植被碳储量反映了绿色植物在光合作用中固定贮存碳的能力, 是物质组分的一个综合指标^[30]。灌木层作为植被碳密度的主体之一, 也是陆地生态系统重要碳汇来源。本研究的灌木层碳密度占整个植被碳密度的41.60%, 表明灌木层是植被碳储量不可忽略的部分。胡会峰等^[9]研究河南灌丛碳密度为624.45 g C· m^-2, 全国灌丛碳密度为10.88 mg C· hm^-2; Woodwell等^[31]估算了全球2.65× 10⁹ hm²灌木林和沙漠灌丛的平均碳密度为10.50 mg C· hm^-2, 而Ni^[6]估算我国灌丛碳密度为45.60 mg C· hm^-2, 而本研究灌木碳密度显著高于以上结果, 主要是由于在植被碳含量研究中, 不同地区、不同植被类型的碳含量存在差异, 不同研究得出结果也不尽相同^{[32, 33]}。目前关于碳密度的研究, 大部分采用平均碳密度方法^{[9, 34]}, 即碳密度等于生物量乘以换算系数0.50或0.45。然而不同物种、不同器官之间碳含量存在差异, 用平均碳密度法会高估生态系统碳密度。而植物碳密度也受植被生物量的影响^[35]。本试验使用不同物种不同器官的含碳率和生物量来计算灌草丛植被的地上碳密度, 结果较为可靠。豫西北地区暖性灌草丛根系总碳密度占植被的93.04%, 表明根系是植被碳密度重要的组成部分。但灌木层根系平均碳密度较草本层低, 约占植被碳密度的40.51%左右, 符合地上地下生物量分布结果。土壤有机碳对生态系统过程、大气组成及气候变化速率的作用及其重要意义已经得到普遍的认同^{[2, 36]}。在豫西北地区暖性灌草丛中, 土壤层有机碳密度为4610.47 g C· m^-2, 占生态系统总碳密度的62.8%。赵威等^[18]计算河南豫西北地区草地土壤碳密度为5.81× 10³ g C· m^-2, 虽然本结果低于上述研究, 但也达到了总碳密度的79.34%, 进一步证实了暖性灌草丛土壤碳库在整个豫西北地区土壤碳库中占有重要地位。

4 结论

豫西北地区暖性灌草丛草地植被碳密度为2360.07 g C· m^-2, 其中灌木层(41.6%)略低于草本层(58.4%), 但差异并不明显。根系是植被碳密度的主要组成, 占植被碳密度的93.04%; 其中灌木层根系碳密度(41.51%)低于草本层(58.49%)。生态系统碳密度约62.8%由土壤所贡献, 其次是根系的19.35%, 地上部分仅贡献了17.85%。综上所述, 豫西北地区暖性灌草丛灌木层在植被碳密度中占很大比重, 如果在固碳研究中忽略了灌木碳储量, 将导致草地生态系统碳储量估算出现较大误差。

The authors have declared that no competing interests exist.

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2007

0.0

... 大气中温室气体逐年增加导致全球变暖日益严重,受到了越来越多国际学者的关注^[1] ...

... 灌木具有种类繁多、生命力强、生产力高、适生范围宽等特点,不仅在群落演替过程中扮演重要角色,在全球碳循环和气候调节中也发挥着重要作用^[1,9] ...

2000

0.0

... 陆地生态系统碳库主要由植被和土壤两部分构成,二者总储量约为大气碳库的3倍,对气候变化和生态系统碳循环具有重要影响^[2,3] ...

... 土壤有机碳对生态系统过程、大气组成及气候变化速率的作用及其重要意义已经得到普遍的认同^{[2, 36]} ...

2012

0.0

. 2012, 32(5):603-608

Soil organic carbon changing with altitudes on the Mountainous Region

伊犁山地不同海拔土壤有机碳的分布

Sun H L , Li W H , Yang Y H

孙慧兰, 李卫红, 杨余辉

1. Xinjiang Laboratory of Lake Environment and Resources in Arid Zone; College of Geography Science and Tourism, Xinjiang National University, Urumqi 830054, China; 2. State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China

Based on data from field investigations and laboratory analysis in 2008 and 2009, soil organic carbon distribution and its influencing factors were studied, taking the northern slope of Wusun Mountain and the southern slope of Keguqin Mountain on the Ili mountainous region, Xinjiang as the study area. The results showed that: 1) Soil organic carbon content in 0-50cm soil layer of alpine meadow and meadow steppe was higher and that was lower in desert steppe. Soil organic carbon content decreased with the increasing of soil depth, both changing range and rate of soil organic carbon content was constant in 0-10cm and 10-20cm soil layer of the Ili mountainous region, however the soil organic carbon content was showed decreasing trend with high changing range in alpine meadow which is on over 2700m above the sea level, and that was slower in Temperate meadow steppe. The desert steppe had the slowest changing range. The difference in decreasing range of soil organic carbon has proved that its vertical distribution pattern was also different; 2) the soil carbon/ nitrogen ratio of southern and northern slope of Ili mountainous region was between7-15 and the soil had higher humification degree and nitrogen mineralization potential. Soil carbon/nitrogen ratio in most sites in different elevation decreased with the increasing of soil depth, and the southern slope of Ili mountainous region had the higher soil carbon/nitrogen decreasing ratio than that of the northern slope; 3) soil organic carbon had a positive significant correlation with soil total nitrogen, total phosphorus and soil moisture (P

以乌孙山北坡、科古琴山南坡为例,分析伊犁山地南北坡土壤有机碳的分布特征和影响因素。结果表明：① 0~50 cm范围内,高寒草甸、草甸草原土壤有机碳含量较高,荒漠草原土壤有机碳含量最低。土壤有机碳含量均随土壤深度的增加而降低,高寒草甸随土壤深度的增加土壤有机碳下降幅度最大;② 伊犁山地土壤腐殖化程度高,氮矿化能力强。大部分海拔的土壤碳氮比随土壤深度的增加而减少。河谷南坡碳氮比降低速率要大于河谷北坡。③ 土壤有机碳与全氮、全磷以及土壤含水率表现出良好的正相关性;与pH值表现出较好的负相关性,特别是20~50 cm处。植被类型分布和人类活动影响对土壤有机碳垂直变化影响显著。

... 陆地生态系统碳库主要由植被和土壤两部分构成,二者总储量约为大气碳库的3倍,对气候变化和生态系统碳循环具有重要影响^[2,3] ...

2010

0.0

... 近年来,我国学者开展了大量有关森林和草地生态系统植被碳储量估算的研究^[4,5,6],但目前对于灌丛生态系统植被生产力与碳储量研究相对缺乏,尤其缺少地下根系和凋落物的数据^[7],导致对碳储量的估算具有极大的不确定性 ...

2004

0.0

2002

0.0

... hm^-2,而Ni^[6]估算我国灌丛碳密度为45 ...

2007

0.0

1986

0.0

... 灌草丛多为森林破坏后形成的次生植被,广泛分布于我国温带地区的丘陵山地,是一种以灌木为优势种、中生和旱中生草本为建群种的主要植被类型^[8] ...

... 3 生物量的测定采用收获法^[8]测定群落植物活体和凋落物生物量 ...

2006

0.0

. 2006, 30(4):539-544

Vegetation carbon storage of major shrublands in China

中国主要灌丛植被碳储量

Hu H F , Wang Z H , Liu G H

胡会峰, 王志恒, 刘国华

(1 State Key Laboratory of Systems Ecosystem, Research Center for Eco_Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China); (2 Department of Ecology, College of Environmental Sciences, Center for Ecological Research & Education, and Key Laboratory for Earth Surface Processes of the Ministry of Education, Peking University, Beijing 100871, China)

Background and Aims Shrublands is one of the major types of terrestrial ecosystems, which widely distributes from tropical to polar regions. Due to their largely distributional area in China, it is very important for us to exactly estimate their carbon storages and spatial distributions. Answers to the following questions were sought: (a) How much is the vegetation carbon storage of major shrublands in China? (b) How are their spatial distributions in China? Methods Based on published biomass data in shrublands and 1∶4 000 000 digital vegetation map of China, carbon storage of major shrublands in China was estimated using the method of mean biomass carbon density for different shrublands types. Key Results The carbon storage of six shrublands in China is 1.68±0.12 Pg C(1 Pg = 10 15 g) with an total area of 15 462.64×10 4 hm 2 . The average vegetation carbon density is 10.88±0.77 Mg C•hm -2 , varying from 5.92 to 17.00 Mg C•hm -2 for different shrubland types. The distribution of shrublands is spatially heterogeneous in the country. Shrublands in three provinces (Yunnan, Guizhou and Sichuan) in Southwest China occupies 23.5% of the total area and contributes to approximately one_third (32.6%) of the total carbon storage of six shrubland types in China due to favorable climeste and soil conditions. The area of six shrubland types in Inner Mongolia is the second largest among all the provinces. However, the vegetation carbon storage in Inner Mongolia shrublands is only 84.81 Tg C (1 Tg = 10 12 g), following that of Yunnan, Guizhou, Sichuan, Jiangxi, and Hunan. The probable reason is ascribed to its arid or semiarid climatic conditions. Although shrublands hold about 1.5 times the area of forests in China, the carbon storage of shrublands corresponds 27%－40% of forests because carbon density of shrublands accounts for only one_fifth of forests. Similarly, the proportion of vegetation carbon storage of shrublands to that of grasslands in China varies from 36% to 55% due to the different areas of grasslands used in previous studies. Conclusion This study draw the following conclusions: (a) As important ecos ystem types in China, shrublands hold large vegetation carbon storage, which is main component of China’s vegetation carbon storage. (b) Because of different climatic and soil conditions, their distributions are spatially heterogeneous in China and The average vegetation carbon density varies greatly for different shrubland types.

在广泛收集资料的基础上，利用植被平均碳密度方法，估算了我国6种主要灌丛植被的碳储量，并分析了其区域分布特征。主要结果如下：1) 6种灌丛植被总面积为15 462.64 ×10 4 hm 2 ，总碳储量为1.68±0.12 Pg C(1 Pg=10 15 g)，灌丛植被平均碳密度为10.88±0.77 Mg C•hm -2 (1 Mg=10 6 g)，不同植被类型差异较大，在5.92～17Mg C•hm -2 之间波动。2) 从区域分布来看，西南3省(云南、贵州、四川)既是我国灌丛主要的分布地区之一，分布面积占6种灌丛总面积的23.5%，又是我国灌丛碳储量的主要储库，碳储量占整个6种灌丛碳储量的1/3（32.6%），适宜的水热条件决定了该地区的植被平均碳密度要高于全国平均水平。3) 与我国森林和草地的植被碳储量相比，这些灌丛碳储量相当于我国森林和草地碳储量的27%～40%和36%～55%。

... 但对于灌草丛的研究主要集中在其地上部分^{[9, 15]},有关地下生物量研究较少 ...

... 灌丛生物量的估算多采用转换因子法^[9],缺乏实测数据,导致估算结果与实测值相差较大 ...

... 10⁸ h m2[16],占我国陆地面积的1/5,是全球现存森林面积的近2倍^[9] ...

... 胡会峰等^[9]研究河南灌丛碳密度为624 ...

... 目前关于碳密度的研究,大部分采用平均碳密度方法^[9,34],即碳密度等于生物量乘以换算系数0 ...

2001

0.0

. 2001, 25(3):366-370

Research progress in relationship between shrub invasion and soil heterogeneity in a natural semiarid grassland

半干旱地区天然草地灌丛化与土壤异质性关系研究进展

Zhang H , Shi P J

张宏, 史培军

The causes and mechanisms of shrub invasion in natural grassland, and the impact on soil resource (soil moisture and available nutrients) heterogeneity caused by shrub invasion of natural grassland are reviewed as are biogeochemical ecosystem processes and the relationship between soil heterogeneity and land degradation in semi-arid areas. Periodic drought and human activity are the two main factors promoting shrub invasion in semiarid areas. Temporal and spatial heterogeneity of soil resources increased with shrub invasion: as soil moisture and available nutrients accumulate under the shrub canopy forming an ‘island of fertility’. Both physical and biological factors show increasing heterogeneity with shrub establishment. Temporal and spatial heterogeneity of soil resources at the patch scale contribute to the initiation of soil erosion and consequent land degradation. Grass and shrub patch mosaic landscapes have low stability and have the highest likelihood of future land degradation. Hence, shrub invasion and shrub density in communities in natural grassland in semi-arid areas should be controlled to prevent soil erosion. Multi-scale analysis of the causes of soil resource heterogeneity in ecosystem are helpful in revealing the mechanisms of land degradation in semi-arid areas.

回顾了半干旱地区天然草地灌丛化的成因和机理、灌丛化导致草地土壤水分和养分空间异质性及其对生态系统生物地球化学过程的影响，以及土壤异质性与土地退化关系等方面的研究进展，周期性气候干旱和过度放牧是天然草地灌丛化的主要原因，伴随灌木入侵而出现的草地土壤水分和养分的空间异质性，是造成生态系统水分和养分流失，以及土壤加速侵蚀的原因之一。因此，半干旱地区天然草地的灌丛化应得到一定的控制，使群落中灌丛保持适宜的密度，以避免生态系统水分和养分的损失。

... 全球气候变暖以及人为干扰影响使得草地灌丛化日益严重^[10,11],以及生物入侵引发的区域碳储量变化,使得灌草丛固碳潜力研究成为新的研究热点^[12,13],而灌草丛面积增加被认为是陆地生态系统碳储量增加的主要原因^[14] ...

2009

0.0

2002

0.0

2002

0.0

2017

0.0

... 3 讨论植被净初级生产力是陆地生态系统碳库的主要来源,植被净初级生产力变化反映了生态系统对气候及土地利用变化的响应^[14] ...

2010

0.0

... 但对于灌草丛的研究主要集中在其地上部分^{[9, 15]},有关地下生物量研究较少 ...

2006

0.0

. 2006, 17(8):1382-1388

Aboveground biomass of three conifers in Qianyanzhou plantation

千烟洲人工林主要树种地上生物量的估算

Li X R , Liu Q J , Chen Y R

李轩然, 刘琪璟, 陈永瑞

1 Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; 2 Graduate University of Chinese Academy of Sciences, Beijing 100039, China; 3 Department of Environment and Resources management, College of Chifeng, Chifeng 024001, China; 4 Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110015, China

In this paper, the regressive models of the aboveground biomass of Pinus elliottii, P. massoniana and Cunninghamia lanceolata in Qianyanzhou of subtropical China were established, and the regression analysis on the dry weight of leaf biomass and total biomass against branch diameter ( d ), branch length ( L ), d 3 and d 2 L was conducted with linear, power and exponent functions. Power equation with single parameter ( d ) was proved to be better than the rests for P. massoniana and C. lanceolata , and linear equation with parameter ( d 3 ) was better for P. elliottii . The canopy biomass was derived by the regression equations for all branches. These equations were also used to fit the relationships of total tree biomass, branch biomass and foliage biomass with tree diameter at breast height ( D ), tree height ( H ), D 3 and D 2 H , respectively. D 2 H was found to be the best parameter for estimating total biomass. For foliageand branch biomass, both parameters and equation forms showed some differences among species. Correlations were highly significant ( P ＜0.001) for foliage-, branch-and total biomass, with the highest for total biomass. By these equations, the aboveground biomass and its allocation were estimated, with the aboveground biomass of P. massoniana, P. elliottii , and C. lanceolata forests being 83.6, 72.1 and 59 t·hm -2 , respectively, and more stem biomass than foliageand branch biomass. According to the previous studies, the underground biomass of these three forests was estimated to be 10.44, 9.42 and 11.48 t·hm -2 , and the amount of fixed carbon was 47.94, 45.14 and 37.52 t·hm -2 , respectively.

利用不同参数和函数,模拟了千烟洲人工林主要树种马尾松、湿地松和杉木的枝条、叶生物量和总生物量及单株各器官生物量,选择最佳函数计算生物量在各树种不同器官中的分配,估算不同林型的地上生物量.结果表明,不同树种的枝条基径( d )和枝条生物量(BW)、叶生物量(LW)之间,当 d 3 为自变量时,相关系数最高,湿地松利用线性函数、马尾松和杉木利用幂函数模拟效果最佳;单木总生物量以利用 D 2 H (胸径 2 ×树高)为自变量的幂函数模拟相关系数最高;3个树种叶和枝生物量各有不同的最佳自变量和函数类型,但同一树种的叶、枝生物量最佳拟合方程的自变量和函数类型一致.马尾松林、湿地松林和杉木林的地上生物量分别为83.6、72.1和59 t·hm -2 ，其中树干生物量所占比重最大，叶生物量最小.根据前人的研究结果推算3种林分地下生物量分别为10.44、9.42和11.48 t·hm -2 ，其固碳量分别为47.94、45.14和37.52 t·hm -2 .

2014

0.0

... 1 研究区概况豫西北地区位于河南境内伏牛山脊和淮河干流的秦岭淮河一线以北,属暖温带、湿润至半湿润季风气候^[17],四季分明,年平均气温10 ...

2018

0.0

... 22 mm^[18] ...

... 赵威等^[18]计算河南豫西北地区草地土壤碳密度为5 ...

1997

0.0

... 1 样地选择在20世纪90年代全国草地类型图和2000土地利用图基础上,结合1997-1998年郭孝等^[19,20]对河南草地的调查结果,选取豫西北地区暖性灌草丛草地,于2017年开展调查研究 ...

1998

0.0

2009

0.0

... 灌草丛生态系统作为一个巨大的潜在碳汇,在全球碳平衡和气候调节中发挥着重要作用^[21] ...

2006

0.0

. 2006, 14(4):310-314

Dynamical characteristics of population component and biomass structure of cultivated Hemarthria compressa grassland

扁穗牛鞭草人工种群构件及生物量动态变化

Liu J P , Zhang X Q , You M H

刘金平, 张新全, 游明鸿

1. Department of Grassland, Sichuan Agriculture University, Ya′an, Sichuan Province 625014, China; 2. Academy of Life Science, West Normal University, Nanchong, Sichuan Province 737002, China; 3. Sichuan Academy of Grassland Science, Chengdu, Sichuan Province 611731, China

Biodiversity is decreasing dramatically with ecological environment deteriorating and human predatory utilization. It has been a critical issue how to protect and study the biodiversity. Hemarthria Compressa is a quality gramineous forage, which is planted in tropical and sub-tropical areas as an excellent grass resource for stockbreeding. In present study, the population component number, distribution, and biomass structure of the cultivated Hemarthria compressa mowing grassland in the different growth period were analyzed. Results show that different curved shapes are seen in the charts among the different parameters. The tiller number of population emerges in an ‘S’ shape during the phenophase. In the early regrowth period and flowering period, the number of secondary tiller is larger than that of the first. When the plant height reaches 50 cm, the number of first tiller which determines the forage yield could ascend to a peak of 3640 tiller/m 2 . During the booting stage when the plant height is about 80 cm, the number of first tiller drops to 2840 tiller/m 2 . Meanwhile, the leaf number of each tiller and of the population are both in an ‘S’ shape shown in the chart. The leaf area of each tiller shows a ‘厂’ shape in the chart, while the leaf area of population gives a typical double ‘S’ shape. In addition, the leaf biomass of each tiller and of the population show an ‘n’ and a double ‘S’ shape, respectively. The number of stem is approximately the same as that of the tiller, though the stem biomass of each tiller and of the population are not shown in an ‘S’ shape synchronously. The aboveground biomass of population is of an ‘S’ shape during the phenophase, while the quality of forage deceases linearly. The changes of the component structure and of the number of population reflect the growth stage and the development condition of the population, which decide the distribution of biomass and the econo-mic outputs. Therefore, scientific and reasonable use and management of the cultivated grassland, based on the growth rhythm of the population, is a key project in the future.

测定扁穗牛鞭草( Hemarthria compressa )人工割草地不同生长时期种群构件数量与分布、生物量结构变化,结果表明:在生育期内种群分蘖数呈现双“S”形变化,在再生初期与开花期二级分蘖数量大于一级分蘖,决定产量的一级分蘖在株高50cm时,数量达最大值3640蘖/cm,到孕穗期(株高约80cm)降为2840蘖/cm;单蘖与叶片数均呈双“S”形变化;单蘖叶面积呈“厂”形变化,而叶面积呈现出典型的双“S”形变化;单蘖和叶片生物量分别呈“n”和双“S”形变化;茎的数量与分蘖数变化一致,单蘖和茎生物量并非同步呈双“S”形变化;地上生物量在生育期内呈“S”形变化;牧草质量呈“直线”形下降。

... 生物量动态变化是反应物质积累与生产潜力的重要指标,也体现了植物的生长规律^[22] ...

2010

0.0

. 2010, 29(11):2146-2154

Biomass distribution and its functioning of forest understory vegetation

东北天然次生林下木树种的生物量器官分配规律

Cheng Y F , Guo Q X , Li X N

程远峰, 国庆喜, 李晓娜

College of Forestry, Northeast Forestry University, Harbin 150040, China

Taking the secondary forest in Maoershan Mountain of Northeast China as study object, the biomass allocation of its understory plants (including tree-like plants and typical shrub categories) was investigated, and the allometry of the components biomass (foliage M L , new branch M NB , old branch M OB , small root M SR , large root M LR , branch M BR , aboveground M AG , and belowground M BG ) versus each other and each component biomass against plant size was analyzed. The biomass allocation of the understory plants complied with allometry theory, and the allometry power exponents of the components biomass were plastic. The M L ∝M NB (0.924-1.055), M OB ∝M LR (0.917-1.024), M BR ∝M LR (1.095-1.164), and M AG ∝M BG (1.064-1.125) were isometry, the power (0.585-0.700) of new branch biomass scaling old branch biomass was nearly to 0.67, the foliage biomass nearly scaled the 0.75 power of branch biomass (0.742-0.795), the power exponent (0.853-0.918) of foliage biomass scaling root biomass was nearly to 0.86, and the allometry power of small root biomass scaling large root biomass was 0.658-0.750. The biomass allocation of understory plants complied with allometry partitioning theory, and the component biomass proportions of foliage, new branch, old branch, small root, and large root were 5.83%-20.60%, 0.83%-7.42%, 36.25%-68.24%, 1.32%-6.75%, and 16.38%-42.88%, respectively, with the root/shoot ratio being 0.272-0.866. The plant biomass allocation partitioning varied with plant species and plant size. For understory plants, the biomass allocation of foliage, new branch, and small root and the root/shoot ratio -decreased significantly ( P P P >0.05).

以帽儿山天然次生林主要下木树种为研究对象，探讨了植物生物量器官（叶、新枝、多年枝、细根、粗根）分配特征及其与物种和个体大小的关系。结果表明：1)林下植物器官生物量的相对生长遵循异速生长理论，相对生长关系并不唯一。叶与新（0.924～1.055）、多年枝与粗根（0.917～1.024）和地上部分与地下部分（1.064～1.125）近于等.速生长，新枝与多年枝（0.585～0.700），叶与总枝（0.742～0.795），叶与总根（0.853～0.918），以及细根与粗根（0.658～0.750）的生物量相对生长表现为异速生长。2)林下植物生物量器官分配遵循异速生长分配理论，叶、新枝、多年枝、细根和粗根等的生物量比例依次是5.83%～20.60%、0.83%～7.42%、36.25%～68.24%、1.32%～6.75%和16.38%～42.88%、根冠比是0.272～0.866。3)器官生物量比例与物种和植物大小等有关，各植物的器官生物量比例有差异，随植物生长，各植物生物量的叶分配、新枝分配、细根分配和根冠比明显减小、多年枝分配明显增加（ P P >0.05）。

... 而植物不同组分生物量分配不仅受外界环境限制,同时还受植物遗传特性和个体差异影响^[23] ...

1999

0.0

... 根据最优分配理论,植物通过调节生物量在各器官中的分配来适应外界环境,以最大限度获取资源,从而维持最大生长速率^[24] ...

1985

0.0

... 而当水分和养分受限时,更多资源会分配到地下根系^[25] ...

2017

0.0

... 灌草丛生物量在群落不同层次之间的分配受群落特性和物种组成等因素的综合影响^[26] ...

2009

0.0

... 凋落物层^[27],本研究中将灌木层与草本层的凋落物进行分别计算,更能准确估算灌木层和草本层各自的固碳量 ...

2013

0.0

. 2013, 33(5):1340-1348 DOI:10.7522/j.issn.1000-694X.2013.00197

Biomass allocation patterns of four shrubs in desert grassland

荒漠草地4种灌木生物量分配特征

Yang H T , Li X R , Liu L C

杨昊天, 李新荣, 刘立超

Shapotou Desert Experiment and Research Station, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China

Biomass mainly reflected the accumulated energy by plant. Plant species have evolved specialized strategies to regulate biomass allocation among various organs or between above- and belowground biomass(R/S). Biomass allocation can affect carbon turnover among different pools and the terrestrial ecosystem carbon cycling. We investigated biomass allocation patterns and characters of root distribution of four common shrubs on individual levels in desert area, southeast of the Tengger Desert, China. Our results indicated that the biomass allocation strategy in above ground organs were different among four shrubs, the R/S were also different. These results reflect every shrub have evolved their unique growth strategy. The canopy and biomass increased and R/S decreased with the growth of shrubs. Shrubs may have higher competition needs for limited resources at the young than older stage. Root biomass distribution are different among Kalidium foliatum (in the uppermost 0-30 cm of the soil), Salsola passerina (in the uppermost 0-50 cm of the soil), Ceratoides latens and Reaumuria soongorica (in the uppermost 0-70 cm of the soil). Reduced major axis analysis showed that the slopes of the relationship between above- and belowground biomass of Ceratoides lateens, Salsola passerine and Reaumuria soongorica close to 1, which support isometric scaling hypothesis. However, the slope of the relationship between above- and belowground biomass of Kalidium foliatum was significantly different from 1.0, which dont support this hypothesis. There is a significant linear relationship between above- and belowground biomass after logarithmic transformation. The relationship can be used to estimate belowground biomass effectively.

生物量是植物积累能量的主要体现,其在各器官中的分配是植物对环境适应的结果,反映了植物的生长策略。生物量分配会影响不同碳库之间的碳周转,进而影响陆地生态系统碳循环。选取腾格里沙漠东南缘荒漠草地的4种优势灌木种,采用全挖法在个体水平上研究了各器官的生物量以及地下-地上生物量关系(根冠比R/S),试图揭示生物量在各器官中以及地下-地上的分配格局。结果表明:不同物种生物量在地上部分各器官中的分配策略不同;R/S也不相同,其中红砂（Reaumuria soongarica）最大(中值为0.972),珍珠（Salsola passerina） (中值为0.744）和驼绒藜（Ceratoides latens）(中值为0.670)次之,盐爪爪（Kalidium foliatum）最小(中值为0.179),这表明4种灌木具有各自独特的生长策略。随着灌木的生长,冠幅和生物量不断增大,R/S呈下降趋势,说明植物在开始生长阶段对限制性的水分和养分可能有更高的竞争需求。4种灌木的根系分布在不同种间也存在差异,盐爪爪根系较浅(主要分布在0～30 cm土层),其次是珍珠（主要分布在0～50 cm土层),驼绒藜和红砂的根系分布较深(主要分布在0～70 cm土层)。驼绒藜、红砂和珍珠的地下-地上生物量分配模式支持等速生长假说,而盐爪爪的地下-地上生物量分配模式则不支持该假说。4种灌木的地上生物量与地下生物量(经对数转换)均呈极显著的线性相关关系(p

... 在灌木层中,老龄枝生物量普遍高于新生枝,叶片生物量最低,可见本地区灌木生物量主要分配在老龄枝中,而新枝所占比重较小,反映了灌木固碳缓慢,这与杨昊天等^[28]的研究结果一致 ...

2001

0.0

... 此外灌木叶片所占比例最小,也与研究地点普遍存在放牧等人为干扰,导致其生物量降低有关^[29] ...

2013

0.0

. 2013, 22(1):112-119 DOI:10.11686/cyxb20130114

The carbon contents and the relationship with the calorific values of 67 plant species in Inner Mongolia grassland

内蒙古草原67种植物碳含量分析及与热值的关系研究

Long S Y , Bao Y J , Li Z H

龙世友, 鲍雅静, 李政海

采用野外取样与室内分析相结合的方法，对内蒙古锡林郭勒３种草原类型中６７种植物的碳含量，以及碳含量和热值的相关关系进行了研究。结果表明，６７种植物的碳含量呈正态分布。基于生活型分类群的碳含量（％）平均值从小到大依次为：一二年生植物（４９．３９±２．８８）＜多年生杂草（５２．３１±１．６５）＜半灌木（５２．８４±１．９０）＜多年生禾草（５３．５４±０．８８），一二年生植物碳含量显著低于其他类群（ P ＜０．０５），其他３个类群之间没有显著性差异（ P ＞０．０５）。基于水分生态类型的碳含量（％）平均值从小到大依次为：旱中生植物（５０．０１±４．３６）＜中生植物（５１．８０±１．９２）＜湿中生植物（５１．９６±０．７８）＜旱生植物（５２．３４±１．９０）＜中旱生植物（５２．５４±１．５３），不同水分生态功能群之间的碳含量无显著性差异（犘＞０．０５）。在基于科的分类群的碳含量中，不同科的植物之间差异显著（ P ＜０．０５），其中：藜科植物的碳含量最低，仅为（４８．４３±２．６５）％。碳含量与热值呈现显著的正相关关系（ r ＝０．５２， P ＜０．０１）。

... 植被碳储量反映了绿色植物在光合作用中固定贮存碳的能力,是物质组分的一个综合指标^[30] ...

1978

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... Woodwell等^[31]估算了全球2 ...

2007

0.0

. 2007, 26(3):307-313

Carbon concentration and its characteristics in terrestrial higher plants

陆生高等植物碳含量及其特点

Zheng W J , Bao W K , Gu B

郑帷婕, 包维楷, 辜彬

1 College of Life Science, Sichuan University, Chengdu 610064, China; 2 Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China

A precise estimation of vegetation carbon storage is the key of illustrating the effects of vegetative restoration on the carbon balance in terrestrial ecosystem. In common, this carbon storage is estimated by carbon concentration coefficient and biomass. This paper collected the actual data of various plants carbon concentration, and analyzed the characteristics of the carbon concentration in different plant life types, plant tissues, and different areas. The results showed that plant carbon concentration was in the range of 24.95%-55.44%, with an average of (43.63±0.14) %. The average carbon concentration of different life types was arbor (46.22%)＞ shrub (45.93%)＞bryophyte (41.64%)＞herbage (37.13%), and that of different tissues was flower (48.52%)＞fruit (47.19%)＞branch (45.42%)＞stem (44.48%)＞leaf (43.36%)＞root (42.88%). As for different geographical areas, the average carbon concentration was high latitude area (50.30%)＞low latitude area (45.30%)＞middle latitude area (39.68%), and there were significant differences among different climatic types. As a result, error always existed when fixed coefficients were used to estimate the carbon storage.

精确评估植被碳贮量是阐明植被恢复对全球陆地生态系统碳平衡影响的核心。碳贮量一般根据碳含量系数与生物量来估计。本文收集了植物碳含量实测数据，分析了不同生长型植物、植物构件和不同区域植物的碳含量状况及其特点，结果表明：植物碳含量在24.95%～55.44%，平均为(43.63±0.14)%；不同生长类型植物平均碳含量是乔木（46.22%）＞灌木（45.93%）＞苔藓（41.64%）＞草本（37.13%）；不同的构件的碳含量是花（48.52% ）＞果（47.19%）＞枝（45.42%）＞干（44.48%）＞叶（43.36%）＞根（42.88%）；不同地带的碳含量是高纬度地区（50.30%）＞低纬度地区（45.30%）＞中纬度地区（39.68%），且不同气候型之间均有显著差异。因此，用固定的碳含量系数来估计碳贮量存在较大误差。

... hm^-2,而本研究灌木碳密度显著高于以上结果,主要是由于在植被碳含量研究中,不同地区、不同植被类型的碳含量存在差异,不同研究得出结果也不尽相同^[32,33] ...

2010

0.0

2014

0.0

. 2014, 50(6):28-33 DOI:10.11707/j.1001-7488.20140604

Carbon density characteristics of two typical shrub communities in the Northern Mountain Region of Hebei

冀北山地2种典型灌丛的碳密度特征

Li Y N , Yu X F , Xu Z Q

李亚男, 虞晓凡, 许中旗

1. College of Forestry, Agricultural University of Hebei Baoding 071000; 2. Key Lab of Genetic Resources of Forest and Forest Protection of Hebei Province Baoding 071000; 3. Mulanweichang National Forestry Administration of Hebei Province Weichang 068400

The carbon density characteristics of two common types of shrubs (including Spiraea pubescens shrub and Corylus heterophylla shrub) were studied in the paper,which are distributed in northern mountain region of Hebei province. The results showed that Spiraea pubescens shrub was higher than Corylus heterophylla shrub in both the carbon density of every parts and total carbon density. The biological carbon density, litter carbon density, soil organ carbon density and total carbon density of Spiraea pubescens shrub were 5.91,0.23,54.31 and 60.44 t·hm -2 ,and those of Corylus heterophylla shrub were 12.81,1.38,141.08 and 155.27 t·hm -2 . The biological carbon density of Spiraea pubescens shrub was lower than the average carbon density of shrub communities of China which was 10.88 t·hm -2 , and that of Corylus heterophylla shrub was higher than that. The total carbon density of Spiraea pubescens shrub was lower than that of Larix gmelinii forest, Populus davidiana forest, Betula platyphylla forest, Quercus mongolica forest and Pinus tabulaeformis forest, and the total carbon density was lower than that of Larix gmelinii forest, Populus davidiana forest, Betula platyphylla forest,and higher than that of Quercus mongolica forest and Pinus tabulaeformis forest. It was concluded that there is significant difference among various shrubs, and there is a bigger carbon density in the shrubs under better site conditions and free of disturbance for long time and the carbon density of shrubs should be considered when the carbon density is evaluated in regional scale, moreover, in order to enhance carbon sequestration of vegetation, some measurements should be carried out to lead a succession from shrubs to forests. Shrubs might be regarded as complementary for forests in carbon sequestration in temporal and spatial aspects.

研究冀北山地常见的2种灌丛（榛子灌丛、土庄绣线菊灌丛）的碳密度特征。结果表明：土庄绣线菊灌丛各个组分的碳密度及总碳密度都明显低于榛子灌丛，土庄绣线菊灌丛的生物碳密度、凋落物碳密度、土壤碳密度和总碳密度分别为5.91，0.23，54.31和60.44 t·hm -2 ，榛子灌丛的生物碳密度、凋落物碳密度、土壤碳密度和总碳密度分别为12.81，1.38，141.08和155.27 t·hm -2 ；土庄绣线菊灌丛的生物碳密度明显低于中国主要6种灌丛的平均值（10.88 t·hm -2 ），而榛子灌丛则高于该平均值；绣线菊灌丛的总碳密度也明显低于该地区的华北落叶松林、山杨林、白桦林、蒙古栎林和油松林，榛子灌丛的总碳密度则低于落叶松林、山杨林和白桦林，但高于油松林和蒙古栎林。由此得出结论：2种灌丛之间的碳密度存在较大差异，未受到明显干扰且立地条件较好的灌丛具有较高的碳密度；在区域植被碳密度的评估中应将灌丛纳入评估范围；应采取有效措施诱导该地区的灌丛向乔木林进行演替，以提高碳截存能力；灌丛的碳截存是乔木林碳汇作用在空间和时间上的补充。

... 目前关于碳密度的研究,大部分采用平均碳密度方法^[9,34],即碳密度等于生物量乘以换算系数0 ...

2007

0.0

. 2007, 27(7):2794-2801

Carbon storage and spatial distribution in Phyllostachy pubescens and Cunninghamia lanceolata plantation ecosystem

竹( Phyllostachy pubescens )、杉木( Cunninghamia lanceolata )人工林生态系统碳贮量及其分配特征

Xiao F M , Fan S H , Wang S L

肖复明, 范少辉, 汪思龙

Chinese fir ( Cunninghamia lanceolata (Lamb.) Hook.) and Moso bamboo ( Phyllostachy pubescens ) are two native and major commercial tree species in South China. Because of their high quality in timber and value in economy, Chinese fir and Moso bamboo have been widely planted in the subtropical area of China. Their distribution area in China are more than 7×10 6 hm 2 for Chinese fir plantation, approximately one fourth of total area of plantation forest in China, and more than 3×10 6 hm 2 for Moso bamboo plantation, accounting for one fifth of the total bamboo forest area in the world. Moso bamboo and Chinese fir plantations are also important for high ecological value in soil preservation, water purification and carbon storage etc.. In order to estimate their carbon storage and its spatial distribution we compared the biomass, carbon concentration between the two plantation based on the survey in their permanent plots. The results showed that the mean carbon concentrations between the two tree species were significantly different, with higher total carbon concentration in Chinese fir than in Moso bamboo. The average carbon concentration in all organs changed in the order of trunk (5043%) > leaf (49.57%) > bark (48.84%) > branch (48.33%) > root (47.89%) for Chinese fir, in the order of sheath (49.91%) > branch (48.46%) > leaf (46.92%) > stem (46.68%) > rhizome (4478%) > root (44.51%) for Moso bamboo. The average carbon concentration in Moso bamboo was not correlated to their age. The carbon concentration of soil to the depth of 60cm ranged from 0.746% to 2.390%, with higher carbon concentration and storage in the soil of 0 -2 0 cm than in the other layer. The total carbon storage of Chinese fir and Moso bamboo plantation ecosystem were 15019 tC•hm -2 and 166.34tC•hm -2 respectively. The spatial distribution pattern of carbon stocks was basically consistent in the order of soil layer > trees layer > shrub and herb and litter layer, with the order of soil (8392%) > trees (1538%) > standing litters (0.38%) > shrub and herb (0.32%) in Moso bamboo plantation forest, and the order of soil (6203%)>trees (34.99%)> standing litters (2.28%) >shrub and herb (0.70%) in Chinese fir plantation. The carbon storage and its allocation among their organs in tree layer were found to be highly correlated with their biomass. Annual carbon fixation of tree layer in Moso bamboo was 9.94tC•hm -2 •a -1 , amounted to 3644 tCO2•hm -2 •a -1 , about 139 times as that of Chinese fir plantation.

研究比较了湖南会同林区毛竹、杉木人工林生态系统碳含量和碳贮量分配特征，结果表明, 15年生杉木各器官碳含量在47.15%～50.43%之间，不同器官碳含量高低依次为树干、树叶、树皮、树枝、树根；毛竹不同器官碳含量波动在44.51%～4991%，各器官碳含量高低依次为竹鞭、竹枝、竹叶、竹干、竹蔸、竹根，但是毛竹不同器官碳含量与年龄之间没有明显变化规律。林地土壤3个层次(60cm深)碳素含量为0.746%～2.390%，各层次碳素含量分布不均，表层（0～20cm）土壤碳素含量和碳贮量最高。毛竹、杉木人工林生态系统碳贮量分别为166.34tC•hm -2 和150.19tC•hm -2 ，并且其碳贮量空间分布格局基本一致, 土壤层是主要部分，其次为乔木层，林下植被层和凋落物层所占比例最小。其中，毛竹林土壤层有机碳贮量占83.92%，乔木层占15.38%，林下植被和凋落物层分别占0.38%和0.32%；杉木人工林土壤层碳贮量占62.03%，乔木层占34.99%，林下植被和凋落物层分别占0.70%和2.28%。另外，碳贮量在两个树种各器官中的分配，基本与各自的生物量成正比例关系。从植被年固定碳量来看，毛竹林为9.94 tC•hm -2 •a -1 ，相当于年固定CO2量为36.44 tCO2•hm -2 •a -1 ，是杉木林的1.39倍。

... 而植物碳密度也受植被生物量的影响^[35] ...

2010

0.0

... 土壤有机碳对生态系统过程、大气组成及气候变化速率的作用及其重要意义已经得到普遍的认同^{[2, 36]} ...