Page 27 - 《广西植物》2025年第8期
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8 期           李金婕等: 云南鸡足山火干扰 40 年形成的云南松林空间分布格局及关联性                                        1 3 9 3

                Spatial distribution patterns and associations of Pinus

                       yunnanensis forest formed by 40 years of fire
                            disturbance in Jizu Mountainꎬ Yunnan



                           1                  1∗               2∗                   2ꎬ3              2
                  LI Jinjie ꎬ ZHANG Caicai ꎬ DENG Yun ꎬ ZHANG Churan ꎬ SU Weihan ꎬ
                                                        4
                                                                            4
                                      4
                           LI Shengfa ꎬ LI Fengchang ꎬ TANG Zhizhong ꎬ LIN Luxiang          2ꎬ5
               ( 1. Institute of Eastern ̄Himalaya Biodiversity Researchꎬ Dali Universityꎬ Dali 671003ꎬ Yunnanꎬ Chinaꎻ 2. CAS Key Laboratory of Tropical
                 Forest Ecologyꎬ Xishuangbanna Tropical Botanical Gardenꎬ Chinese Academy of Sciencesꎬ Mengla 666303ꎬ Yunnanꎬ Chinaꎻ 3. Key
                    Laboratory for Transboundary Ecosecurity of Southwest China of Ministry of Educationꎬ School of Ecology and Environmental
                      Scienceꎬ Yunnan Universityꎬ Kunming 650091ꎬ Chinaꎻ 4. Yu Jinan State ̄Owned Forest Farmꎬ Dali 671009ꎬ Yunnanꎬ
                         Chinaꎻ 5. National Forest Ecosystem Research Station at Xishuangbannaꎬ Mengla 666303ꎬ Yunnanꎬ China )

                 Abstract: Pinus yunnanensisꎬ native to southwest Chinaꎬ is widely used as a pioneer species for afforestation. Large
                 areas of P. yunnanensis natural forests and plantations provide abundant forestry resourcesꎬ playing a key role in forestry
                 construction and sustainable development. Howeverꎬ the high oil content and low ignition point of P. yunnanensis make it
                 susceptible to frequent wildfiresꎬ especially with the intensification of global change. To investigate the community
                 compositionꎬ spatial distribution patterns and associations of dominant species in early post ̄fire regeneration of P.
                                     2
                 yunnanensis forestsꎬ a 1 hm dynamic monitoring plot of P. yunnanensis forest was established in Jizu Mountainꎬ Yunnan
                 Provinceꎬ following the standard protocol of the Forest Global Earth Observatory. This area was a subtropical semi ̄humid
                 evergreen broad ̄leaved forest 40 years ago. Community composition and diameter structures based on census data were
                 analyzed. The g(r) function was used to analyze the spatial patterns and associations between P. yunnanensis in different
                 diameter classes and dominant woody plants with different leaf habits. The results were as follows: (1) There were 3 088
                 individuals (DBH≥1cm)ꎬ belonging to 30 species from 14 families and 21 generaꎬ including 23 evergreen and 7
                                    2
                 deciduous species in 1 hm dynamic plot. (2) The diameter structure of P. yunnanensis and Populus adenopoda was
                 skew ̄normal and belonged to stable populations. While the diameter structure of Viburnum cylindricumꎬ Pinus armandii
                 and Pieris formosa was inverted “J” typeꎬindicating successful regeneration of evergreen plants with a higher number of
                 small ̄diameter individualsꎬ which suggested that they might eventually replace P. yunnanensis forests. (3) The spatial
                 distribution of P. yunnanensis at three developmental stages (saplingsꎬ juvenilesꎬ adults) was mainly aggregatedꎬ and
                 the distribution of adults may shift from aggregated to random or uniform distribution patterns as the scale increases. (4)
                 The saplings of P. yunnanensis were mainly positively correlated with juvenile and adult treesꎬ while juvenile and adult
                 trees were uncorrelatedꎬ indicating a healthy relationship within the P. yunnanensis population. Additionallyꎬ P.
                 yunnanensis showed negative or no correlation with the dominant evergreen and deciduous plantsꎬ indicating competition
                 for limited resources such as light and water. In summaryꎬ the structure of the P. yunnanensis community is stableꎬ and
                 P. yunnanensis remains the dominant species in the early stage of community succession. The spatial distribution of its
                 different developmental stages is dominated by aggregation. Howeverꎬ the distribution of adults may shift to random or
                 uniform distributions in the futureꎬ reflecting the cumulative effects of negative density ̄dependence. Positive spatial
                 associations between different diameter classes are also an important feature in the early stage of community
                 succession. Howeverꎬ as succession progressesꎬ evergreen plants may replace the dominant position of P. yunnanensisꎬ
                 leading the community towards a subtropical semi ̄humid evergreen broad ̄leaved forest.
                 Key words: Pinus yunnanensisꎬ spatial distributionꎬ diameter structureꎬ spatial associationꎬ succession



                种群年龄结构指不同年龄的个体在时间和空                            学特性和所在环境共同决定的ꎬ能够体现种群当
            间上的组成和装配情况ꎬ它是由种群自身的生物                              前的结构状态、对环境的适应能力及生存现状和
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