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WU Renjie, XING Wei, GE Zhiwei, MAO Lingfeng, PENG Sili. Stoichiometric characteristics of leaf litter at different decomposition stages in 4 forest types[J]. Journal of Zhejiang A&F University, 2023, 40(1): 155-163. doi: 10.11833/j.issn.2095-0756.20220289
Citation: WU Renjie, XING Wei, GE Zhiwei, MAO Lingfeng, PENG Sili. Stoichiometric characteristics of leaf litter at different decomposition stages in 4 forest types[J]. Journal of Zhejiang A&F University, 2023, 40(1): 155-163. doi: 10.11833/j.issn.2095-0756.20220289

Stoichiometric characteristics of leaf litter at different decomposition stages in 4 forest types

doi: 10.11833/j.issn.2095-0756.20220289
  • Received Date: 2022-04-09
  • Accepted Date: 2022-07-22
  • Rev Recd Date: 2022-07-19
  • Available Online: 2023-01-18
  • Publish Date: 2023-01-17
  •   Objective  This research aims to study the stoichiometric characteristics of leaf litter at different decomposition stages in different stands in southwest Guizhou Province, so as to better understand the nutrient cycling law of different forest ecosystems in karst areas.   Method  4 typical forest types were selected in southwest Guizhou, including Pinus massoniana forest, Phyllostachys edulis forest, Cunninghamia lanceolata forest, and natural forest dominated by Quercus acutissima, Machilus cavaleriei and Cyclobalanopsis glaucoides. Leaf litter at different decomposition stages was collected and stoichiometric characteristics of C, N and P were measured.   Result  (1) The total C content of leaf litter in each decomposition stage of P. edulis forest was significantly lower than that in other stands (P<0.05), and the total C content of leaf litter at decomposed stage of P. massoniana and C. lanceolata forests was significantly lower than that at undecomposed and semi-decomposed stages (P<0.05). The total N content of leaf litter in C. lanceolata forest at undecomposed stage was significantly lower than that at semi-decomposed and decomposed stages (P<0.05). The total P content of leaf litter at decomposed stage of natural forest was significantly higher than that in other stands (P< 0.05), and the total P content at semi-decomposed stage of natural forest was significantly lower than that at undecomposed and decomposed stages (P< 0.05). (2) The C/N ratio of C. lanceolata forest at decomposed stage was significantly higher than that of Ph. edulis forest (P<0.05), and the C/N ratio at undecomposed stage was significantly higher than that at semi-decomposed and decomposed stages (P<0.05). The N/P ratio at undecomposed and decomposed stages of Ph. edulis forest was significantly higher than that of natural forest (P<0.05). The C/P ratio of leaf litter at semi-decomposed stage of C. lanceolata and natural forests was significantly lower than that of P. massoniana forest (P< 0.05), and the C/P ratio at decomposed stage of natural forest was significantly lower than that of other stands (P<0.05).   Conclusion  Both forest type and decomposition stage have significant effects on contents of total C, N and P, as well as stoichiometric characteristics of leaf litter. [Ch, 2 fig. 2 tab. 36 ref.]
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Stoichiometric characteristics of leaf litter at different decomposition stages in 4 forest types

doi: 10.11833/j.issn.2095-0756.20220289

Abstract:   Objective  This research aims to study the stoichiometric characteristics of leaf litter at different decomposition stages in different stands in southwest Guizhou Province, so as to better understand the nutrient cycling law of different forest ecosystems in karst areas.   Method  4 typical forest types were selected in southwest Guizhou, including Pinus massoniana forest, Phyllostachys edulis forest, Cunninghamia lanceolata forest, and natural forest dominated by Quercus acutissima, Machilus cavaleriei and Cyclobalanopsis glaucoides. Leaf litter at different decomposition stages was collected and stoichiometric characteristics of C, N and P were measured.   Result  (1) The total C content of leaf litter in each decomposition stage of P. edulis forest was significantly lower than that in other stands (P<0.05), and the total C content of leaf litter at decomposed stage of P. massoniana and C. lanceolata forests was significantly lower than that at undecomposed and semi-decomposed stages (P<0.05). The total N content of leaf litter in C. lanceolata forest at undecomposed stage was significantly lower than that at semi-decomposed and decomposed stages (P<0.05). The total P content of leaf litter at decomposed stage of natural forest was significantly higher than that in other stands (P< 0.05), and the total P content at semi-decomposed stage of natural forest was significantly lower than that at undecomposed and decomposed stages (P< 0.05). (2) The C/N ratio of C. lanceolata forest at decomposed stage was significantly higher than that of Ph. edulis forest (P<0.05), and the C/N ratio at undecomposed stage was significantly higher than that at semi-decomposed and decomposed stages (P<0.05). The N/P ratio at undecomposed and decomposed stages of Ph. edulis forest was significantly higher than that of natural forest (P<0.05). The C/P ratio of leaf litter at semi-decomposed stage of C. lanceolata and natural forests was significantly lower than that of P. massoniana forest (P< 0.05), and the C/P ratio at decomposed stage of natural forest was significantly lower than that of other stands (P<0.05).   Conclusion  Both forest type and decomposition stage have significant effects on contents of total C, N and P, as well as stoichiometric characteristics of leaf litter. [Ch, 2 fig. 2 tab. 36 ref.]

WU Renjie, XING Wei, GE Zhiwei, MAO Lingfeng, PENG Sili. Stoichiometric characteristics of leaf litter at different decomposition stages in 4 forest types[J]. Journal of Zhejiang A&F University, 2023, 40(1): 155-163. doi: 10.11833/j.issn.2095-0756.20220289
Citation: WU Renjie, XING Wei, GE Zhiwei, MAO Lingfeng, PENG Sili. Stoichiometric characteristics of leaf litter at different decomposition stages in 4 forest types[J]. Journal of Zhejiang A&F University, 2023, 40(1): 155-163. doi: 10.11833/j.issn.2095-0756.20220289
  • 凋落物是森林生态系统中植被代谢的产物。凋落物分解对森林土壤有机质形成和植被群落组成起着决定性作用[1-2],是维持森林生态系统物质循环和能量流动的关键因素[3-5]。凋落物分解包括从新鲜凋落物到粗腐殖质,粗腐殖质进一步分解为腐殖质2个阶段。新鲜凋落物分解为腐殖质的过程中会逐步释放营养元素,使处于不同分解阶段的凋落物养分含量及化学计量比不同。凋落叶作为凋落物的主要组成成分,分解速度快,在养分循环中占据重要的地位[6]。据统计,森林土壤中至少有90%的氮和磷、60%的其他矿质元素来自凋落叶的分解归还[7],因此,凋落叶分解对土壤性质产生直接影响[8],对土壤有机质提升和养分积累具有重要作用。同时,土壤中碳氮磷养分元素及化学计量比也在不同程度上影响凋落叶的分解[9-10],尤其是氮磷元素在诸多生态系统中会对凋落叶分解产生复杂的交互作用。此外,环境因子也与凋落叶分解密切相关,其中温度和湿度被认为是影响凋落叶分解的主要因子。温度和湿度可以直接或通过改变凋落叶质量、土壤酶活性、土壤微生物活性及植被群落组成间接影响凋落叶分解[11]。因此,研究凋落叶不同分解阶段化学计量特征及影响因素,可深入了解其在分解过程中养分归还状况。

    黔西南地区地势西高东低,大部分地区为山地与丘陵,石漠化问题严重,是典型的喀斯特生境和生态脆弱区[12]。该区森林类型丰富,不仅分布有马尾松Pinus massoniana林、毛竹Phyllostachys edulis林、杉木Cunninghamia lanceolata林等人工林,还有以滇青冈Cyclobalanopsis glaucoides、麻栎Quercus acutissima、安顺润楠Machilus cavaleriei等为优势种的天然林。为了更好地了解喀斯特地区森林养分循环规律,为喀斯特地区生态系统恢复重建和科学管理提供理论指导,研究者探究了植被与土壤间碳氮磷化学计量特征[13-16]及不同林分类型凋落物的养分释放规律和归还特征[17-19]。由于对凋落物养分释放特征的研究时长较短,忽略了凋落物在长期分解过程中的营养元素释放规律和迁移特征对森林生态系统养分循环产生的影响。本研究利用空间代替时间的方法,以马尾松林、毛竹林、杉木林以及天然林为对象,根据凋落叶分解状态,将凋落叶分为未分解层、半分解层和已分解层[20-22],采集并测定了处于3种分解阶段凋落叶的全碳、全氮和全磷质量分数,同时,测定了不同林分土壤环境因子,并对凋落叶化学计量特征与环境因子间的相关关系进行了分析,以期为喀斯特地区森林生态系统养分循环以及生态系统功能研究奠定基础。

    • 研究区位于贵州省西南部的兴义市、望谟县、平坝县和普定县境内(24°42′45″~26°31′36″N,104°38′39″~106°14′08″E),属亚热带湿润季风气候,平均海拔为1 443.5 m,年平均气温为14.8 ℃,年平均降水量为1 100~1 400 mm。该区分布有马尾松、毛竹、杉木、麻栎、大叶青冈Cyclobalanopsis jenseniana、云山青冈C. sessilifolia、滇青冈、安顺润楠等林分类型。林下植被以悬钩子属Rubus、狗脊Woodwardia japonica、里白Diplopterygium glaucum、芒萁Dicranopteris pedata、紫萁Osmunda japonica等为主。选取该区4种典型林分类型(马尾松林、毛竹林、杉木林和以麻栎、安顺润楠和滇青冈为优势种组成的天然林),每种林分分别设置3个20 m×20 m的样地。样地基本信息如表1所示。

      林分类型纬度(N)经度(E)海拔/m坡位坡向坡度/(°)郁闭度/%干扰程度经营措施
      马尾松林 24°42′45″ 104°38′39″ 1 050 中  南偏西7° 25.0 50 去除林下植被、无施肥
      26°29′59″ 106°12′15″ 1 480 上  南偏东75° 20.0 30 去除林下植被、无施肥
      26°29′54″ 106°12′13″ 1 444 下  东南 9.0 58 去除林下植被、无施肥
      毛竹林  26°31′36″ 106°14′08″ 1 462 下  7.5 80 去除林下植被、无施肥
      26°31′36″ 106°14′08″ 1 500 中  南偏西60° 12.0 50 去除林下植被、无施肥
      26°31′36 106°14′05″ 1 476 中  东南 8.0 85 去除林下植被、无施肥
      杉木林  24°59′48″ 104°48′44″ 1 890 中  北偏西15° 16.0 40 去除林下植被、无施肥
      25°22′09″ 106°08′02″ 1 530 中  北偏东60° 45.0 70 去除林下植被、无施肥
      25°14′01″ 106°08′40″ 1 250 上  南偏东60° 15.0 70 去除林下植被、无施肥
      天然林  25°22′00″ 106°08′02″ 1 490 下  北偏西60° 40.0 70 无经营措施     
      25°06′15″ 105°05′25″ 1 330 上  30.0 80 无经营措施     
      26°14′44″ 105°45′36″ 1420 中上 北偏东58° 39.0 60 无经营措施     

      Table 1.  Information table of sample plots

    • 2020年11月5—20日采集样地中的凋落叶。具体做法是:在每个样地内随机选取3个面积为1 m2的小样方,将每个小样方中的凋落叶分为未分解(可看清凋落叶形状,多为新鲜叶片)、半分解(凋落叶进入分解发酵阶段,形状不完整,包含杂质,与未分解凋落叶有明显的区别)和已分解(看不出凋落叶形状,为腐殖质状态)3种类型,分别进行采集,采集量为2.28~4.36 t·hm−2。采集完成后将同一个样地中的3个小样方对应层次的凋落叶混合均匀,共取得36个样品。同时,采集样方中0~10 cm土壤,并混合均匀,并用土壤温度测试仪测定并记录土壤温度。

      将凋落叶和土壤装入自封袋带回实验室,凋落叶在65 ℃下烘干至恒量,全自动研磨仪磨碎,过100目筛;土壤自然风干过100目筛。测定凋落叶和土壤全碳(TC)、全氮(TN)和全磷(TP)质量分数。全碳和全氮采用元素分析仪(PE 2400Ⅱ ,美国)进行测定,全磷采用碱熔-钼锑抗比色法测定[23]。土壤pH采用玻璃电极法测定(土水比为1.0∶2.5);土壤含水率采用鲜土烘干法测定。

    • 利用Excel 2010对数据进行处理,采用SPSS 24.0对凋落叶化学计量特征进行双因素(林分类型和凋落叶分解阶段)方差分析,并在林分类型和分解阶段下对化学计量特征进行单因素方差分析(one-way ANOVA),采用LSD法(P<0.05)对各指标在不同处理间的差异进行显著性分析,采用Pearson检验分析凋落叶化学计量特征与环境因子的相关性,用Origin 2018作图。

    • 双因素(林分类型和凋落叶分解阶段)方差分析表明:林分类型对全碳、全氮和全磷质量分数均产生显著影响(P<0.05),凋落叶分解阶段对全碳和全磷质量分数有显著影响(P<0.05)。随着凋落叶分解程度的加剧,全碳质量分数呈现降低趋势;全氮质量分数呈现升高趋势;全磷质量分数除天然林呈升高趋势外,其余呈现降低趋势。两者交互效应对全碳、全氮和全磷质量分数均无显著影响。

      图1可见:各林分类型凋落叶各分解阶段全碳质量分数总和从大到小为天然林(1 466.37 mg·g−1)、马尾松林(1 465.07 mg·g−1)、杉木林(1 455.93 mg·g−1)、毛竹林(1 246.53 mg·g−1)。随着凋落叶分解程度的加剧,4种林分凋落叶全碳质量分数均呈现降低趋势,其中,马尾松林和杉木林凋落叶已分解阶段全碳质量分数均显著低于未分解和半分解阶段(P<0.05),其余2种林分在不同分解阶段无显著差异。不同林分类型凋落叶全碳质量分数具有明显差异,毛竹林凋落叶全碳质量分数在各分解阶段下均显著低于其余3种林分(P<0.05)。

      Figure 1.  Carbon, nitrogen and phosphorus contents of leaf litters in different decomposition stages in four forest types

      各林分类型凋落叶各分解阶段全氮质量分数总和从大到小依次为毛竹林(47.53 mg·g−1)、天然林(42.4 mg·g−1)、杉木林(32.57 mg·g−1)、马尾松林(31.9 mg·g−1)。随着凋落叶分解程度的加剧,马尾松林和天然林凋落叶全氮质量分数先减少后增加;毛竹林逐渐增加;杉木林先增加后减少,且未分解阶段显著低于半分解和已分解阶段(P<0.05)。在不同林分类型凋落叶中,全氮质量分数在各分解阶段均无显著差异。

      各林分类型凋落叶各分解阶段全磷质量分数总和从大到小依次为天然林(8.20 mg·g−1)、杉木林(4.49 mg·g−1)、马尾松林(4.39 mg·g−1)、毛竹林(4.17 mg·g−1)。随着凋落叶分解程度的加剧,杉木林凋落叶全磷质量分数呈现逐渐降低趋势;马尾松林、毛竹林和天然林凋落叶全磷质量分数呈现先降低后升高的趋势,其中,天然林半分解阶段显著低于未分解和已分解阶段(P<0.05)。对不同林分类型进行分析,在半分解阶段中,马尾松林和毛竹林凋落叶全磷质量分数均显著低于天然林(P<0.05);已分解阶段,马尾松林、杉木林和毛竹林凋落叶全磷质量分数均显著低于天然林(P<0.05)。

    • 双因素(林分类型和凋落叶分解阶段)方差分析表明:林分类型和凋落叶分解阶段对其化学计量比均产生显著影响(P<0.05):随着凋落叶分解程度的加剧,凋落叶碳氮比和氮磷比分别呈现出降低和升高的趋势;对于凋落叶碳磷比而言,马尾松林和天然林呈降低趋势,毛竹林和杉木林呈升高趋势。两者交互效应对凋落叶碳氮比、氮磷比和碳磷比均无显著影响。

      4种林分类型不同分解阶段凋落叶碳氮比、氮磷比和碳磷比如图2所示。马尾松林、毛竹林、杉木林和天然林凋落叶碳氮比平均值分别为52.72、27.09、48.11、42.72,凋落叶碳氮比随凋落叶逐渐分解大体呈现出降低趋势,杉木林半分解和已分解阶段碳氮比显著低于未分解阶段(P<0.05)。对不同林分类型进行分析,杉木林已分解阶段碳氮比显著高于毛竹林(P<0.05)。

      Figure 2.  Carbon, nitrogen and phosphorus stoichiometry characteristicsof leaf litters in different decomposition stages in four forest types

      马尾松林、毛竹林、杉木林和天然林凋落叶氮磷比平均值分别为7.87、12.39、7.99、7.97。随着凋落叶分解程度的加剧,马尾松林和杉木林凋落叶氮磷比呈现逐渐升高的趋势;毛竹林和天然林凋落叶氮磷比呈现先升高后降低的趋势,且各分解阶段之间无显著差异。对不同林分类型进行分析,在未分解和已分解阶段中,天然林氮磷比显著低于毛竹林(P<0.05),半分解阶段中无显著差异。

      马尾松林、毛竹林、杉木林和天然林凋落叶碳磷比平均值分别为381.35、324.66、349.26、227.82。随着凋落叶分解程度的加剧,马尾松林、毛竹林和天然林凋落叶碳磷比呈现先升高后降低的趋势;杉木林凋落叶碳磷比呈先降低后升高的趋势;天然林半分解阶段凋落叶碳磷比显著高于未分解和已分解阶段(P<0.05)。对不同林分类型进行分析,在半分解阶段中,杉木和天然林凋落叶碳磷比均显著低于马尾松林(P<0.05),已分解阶段中,天然林凋落叶碳磷比显著低于其余3种林分(P<0.05)。

    • 凋落叶全碳、全氮、全磷质量分数及化学计量特征与环境因子相关分析如表2所示。凋落叶全碳质量分数与土壤温度和坡度极显著正相关(P<0.01),与林分郁闭度显著负相关(P<0.05);凋落叶全氮质量分数与坡位和土壤含水率显著负相关(P<0.05);凋落叶全磷质量分数与土壤碳氮比显著负相关(P<0.05),与土壤氮磷比、土壤碳磷比、土壤温度、土壤pH、坡度显著正相关(P<0.05, P<0.01)。

      项目凋落叶全碳凋落叶全氮凋落叶全磷凋落叶碳氮比凋落叶氮磷比凋落叶碳磷比
      土壤全碳 0.125 −0.047 0.130 0.136 −0.041 −0.093
      土壤全氮 0.110 −0.022 0.265 0.124 −0.122 −0.243
      土壤全磷 0.052 −0.074 −0.229 0 0.104 0.217
      土壤碳氮比 0.073 −0.029 −0.336* 0.022 0.262 0.386*
      土壤氮磷比 0.231 −0.220 0.377* 0.296 −0.341* −0.343*
      土壤碳磷比 0.230 −0.222 0.332* 0.296 −0.305 −0.295
      土壤温度 0.439** −0.193 0.565** 0.267 −0.556** −0.418*
      土壤含水率 −0.007 −0.340* −0.318 0.251 0.013 0.253
      土壤pH 0.167 −0.224 0.461** 0.216 −0.462** −0.453**
      海拔 0.015 0.013 −0.275 −0.075 0.190 0.239
      郁闭度 −0.419* 0.197 −0.192 −0.212 0.371* 0.086
      坡度 0.450** −0.096 0.469** 0.187 −0.456** −0.358*
      坡位 0.282 −0.386* 0.256 0.328 −0.411* −0.217
        说明:*和**分别表示在P<0.05和P<0.01下显著相关

      Table 2.  Pearson correlations between stoichiometric characteristics of leaf litters and environmental factors

      凋落叶全碳、全氮、全磷化学计量与环境因子的关系是:凋落叶碳氮比除与海拔和林分郁闭度呈负相关关系外,与其余环境因子均呈正相关关系,但相关性不显著;对凋落叶氮磷比而言,除受土壤氮磷比影响外(P<0.05),还与土壤温度、土壤pH、坡位、坡度呈显著负相关关系(P<0.05, P<0.01),与林分郁闭度呈显著正相关(P<0.05);凋落叶碳磷比与土壤碳氮比和土壤氮磷比分别呈显著正相关和负相关(P<0.05),还与土壤温度、土壤pH、坡度呈显著负相关(P<0.05, P<0.01)。

    • 凋落叶在分解过程中养分释放大致分为3种模式:①直接释放,养分含量出现延续性减少状态;②淋溶—富集—释放,养分含量先减少后增多再减少,这一过程中养分含量变化具有较大的波动性;③富集—释放,为了满足微生物参与凋落叶分解过程的需要,养分含量随时间变化先升高后降低[24]。本研究中,不同养分元素的释放规律有所差异。4种林分凋落叶全碳质量分数呈直接释放规律,从大到小均表现为未分解层、半分解层、已分解层。这与赵畅等[25]研究结果类似,凋落叶分解过程中可溶性糖和有机质的损失,以及分解微生物的消耗都可能造成碳的减少。对氮元素而言,马尾松林和天然林呈现淋溶—富集规律,表明凋落叶分解过程中为满足微生物生命活动的需要而吸收了一定量的氮。SULKAVA等[26]研究指出:马尾松林凋落物在分解过程中氮呈现出的富集规律,杉木林和毛竹林也呈现富集规律。这是由于氮的释放滞后于凋落叶的质量损失。杉木林凋落叶中全磷为直接释放,表明杉木林更易受到磷元素的限制。凋落叶碳氮比、碳磷比和氮磷比反映其自身分解速率及植物生长过程中受何种元素的限制[27]。随着凋落叶逐渐分解,杉木林碳氮比显著降低,与王书丽等[27]研究的研究结果一致,表明其分解初期受微生物影响分解迅速;天然林凋落叶碳磷比未分解阶段显著高于其分解阶段,这可能是由于土壤微生物对磷的固持效应相关[28];4种林分凋落叶分解后期氮磷比均有增大趋势,证明林分易受到氮或磷元素的限制。

    • 林分类型可以直接或通过改变土壤微生物群落结构间接影响凋落叶养分及化学计量特征[29-30],这与本研究得出的林分类型对其影响显著的结果一致。含氮量较高的凋落叶会降低分解惰性碳的微生物活性[31],其碳的留存量会升高。本研究得出毛竹林高氮低碳的结论,证明了林分类型影响凋落物养分释放,通常与林分自身性质相关。本研究发现毛竹林全磷质量分数低于马尾松林,这可能是由于该地区土壤微环境不同而导致。马尾松林、毛竹林、杉木林、天然林凋落叶全氮平均质量分数分别为10.63、15.84、10.86、14.13 mg·g−1,全磷平均质量分数分别为1.46、1.39、1.50、2.73 mg·g−1,均高于全球森林凋落叶氮(10.0 mg·g−1)和磷(0.7 mg·g−1)质量分数[32]。这可能与氮、磷元素重吸收程度有关。本研究得出所有林分凋落叶碳氮比、碳磷比和氮磷比均小于全球森林的平均水平[33],碳磷比也低于亚热带常绿阔叶林和亚热带人工林凋落叶平均值[34],这与该地区富含大量磷元素有关。氮磷比较小除与该区富含磷元素有关,还可能受叶片结构的影响。

    • 凋落叶分解主要受非生物因素和生物因素共同影响[35]。非生物因素包括环境因子、凋落叶自身质量等,生物因素包括土壤微生物丰富度和多样性。土壤化学计量比、土壤pH、土壤温度和土壤湿度通过改变土壤微生物群落结构间接影响凋落叶的养分释放[36]。在本研究中,土壤化学计量比、土壤温湿度、土壤pH、林分郁闭度、坡度对凋落叶养分质量分数均有显著影响。较高的土壤湿度改变了土壤微生物的生长活性,影响凋落叶中氮的释放,进而改变了凋落叶碳氮比。本研究得出土壤含水率、土壤温度、土壤pH、坡度与凋落叶碳氮比相关不显著,尤其是土壤含水率对凋落叶化学计量比之间的相关均不显著,这是因为该区气温较高、林分郁闭度大的特点影响了某些土壤微生物群落对凋落叶的分解活动。坡度通过改变土壤表面径流影响凋落叶养分分布规律;郁闭度改变了由水热变化引起的一系列生物化学过程从而导致凋落叶的养分迁移;海拔可以通过改变气温和降水间接影响凋落叶分解。海拔对凋落叶养分及其化学计量比的影响不显著的可能原因是本研究没有在大范围尺度上研究海拔与凋落叶养分之间的关系。

    • 林分类型对凋落叶养分质量分数及化学计量特征均有显著影响,凋落叶分解阶段对全碳和全磷质量分数及化学计量特征均有显著影响。随着凋落叶分解程度的加剧,4种林分凋落叶全碳质量分数均呈现出释放规律,马尾松林和杉木林已分解阶段全碳质量分数均显著低于未分解和半分解阶段;杉木林全氮质量分数呈现富集—释放的规律;天然林全磷质量分数呈现淋溶—富集的规律。杉木林未分解阶段凋落叶碳氮比显著高于半分解和已分解阶段;天然林碳磷比先升高后降低,且其半分解阶段碳磷比显著高于未分解和已分解阶段。

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