Variations of plant life form diversity along the Northeast China Transect and its direct gradient analysis

Plant life form diversity and its direct gradient analysis on a larger scale climate change gradient were tested, based on the data from Northeast China Transect platform. The results showed that the species numbers, life form richness and life form diversity were relative higher at the eastern forests and the ecotone between typical vegetation, while those on the meadow grasslands and typical steppes were lower. Although plant life forms can reflect the climate variations, life form diversity is not consistent with the major global gradient along the NECT.

Host plant traits play a crucial role in shaping the composition of epiphytic microbiota in the arid desert,Northwest China

Phyllosphere microorganisms are a crucial component of environmental microorganisms,highly influenced by host characteristics,and play a significant role in plant health and productivity.Nonetheless,the impact of host characteristics on shaping phyllosphere microbial communities of plants with different life forms remains ambiguous.Utilizing high-throughput sequencing technology,this study analyzed the diversity and community composition of phyllosphere epiphytic microorganisms(e.g.,bacteria and fungi)of various plant life forms in the hinterland of the Gurbantunggut Desert,Northwest China.Functional annotation of prokaryotic taxa(FAPROTAX)and fungi function guild(FUNGuild)were employed to assess the ecological functions of microorganisms and to investigate the role of stochastic and deterministic processes in shaping phyllosphere microbial communities.Result showed a diverse array of phyllosphere epiphytic microorganisms in the desert plants,with Proteobacteria,Cyanobacteria,and Actinobacteriota dominating bacterial community,while Ascomycota and Basidiomycota were prevalent in fungal community.Comparison across different plant life forms highlighted distinct microbial communities,indicating strong filtering effects by plant characteristics.FAPROTAX prediction identified intracellular parasites(accounting for 27.44%of bacterial community abundance),chemoheterotrophy(10.12%),and phototrophy(17.41%)as the main functions of epiphytic bacteria on leaves of different life form plants.FUNGuild prediction indicated that phyllosphere epiphytic fungi primarily served as Saprotrophs(81.77%),Pathotrophs(17.41%),and Symbiotrophs(0.82%).Co-occurrence network analysis demonstrated a predominance of positive correlations among different microbial taxa.Raup-Crick dissimilarity index analysis revealed that deterministic processes predominantly influenced phyllosphere bacterial and fungal community assembly.Variance partitioning analysis and random forest modeling suggested that plant leaf functional traits significantly impacted both bacterial and fungal community composition,with fungal community composition showing a closer association with leaf nutrients and physiology compared with bacterial community composition.The distinct responses of bacterial and fungal communities to plant traits were attributed to the differing properties of bacteria and fungi,such as bacteria having higher potential dispersal rates and broader ecological niches than fungi.Overall,the results indicate that phyllosphere bacterial and fungal communities undergo similar community assembly processes,with fungi being more influenced by plant characteristics than bacteria.These findings offer novel insights into the ecology of phyllosphere microbial communities of desert plants.

Ecological biomass allocation strategies in plant species with different life forms in a cold desert, China

Biomass allocation patterns among plant species are related to their adaptive ecological strategies. Ephemeral, ephemeroid and annual plant life forms represent three typical growth strategies of plants that grow in autumn and early spring in the cold deserts of China. These plants play an important role in reducing wind velocity in the desert areas. However, despite numerous studies, the strategies of biomass allocation among plant species with these three life forms remain contentious. In this study, we conducted a preliminary quadrat study during 2014–2016 in the southern part of the Gurbantunggut Desert, China, to investigate the allocation patterns of above-ground biomass(AGB) and below-ground biomass(BGB) at the individual level in 17 ephemeral, 3 ephemeroid and 4 annual plant species. Since ephemeral plants can germinate in autumn, we also compared biomass allocation patterns between plants that germinated in autumn 2015 and spring 2016 for 4 common ephemeral species. The healthy mature individual plants of each species were sampled and the AGB, BGB, total biomass(TB), leaf mass ratio(LMR) and root/shoot ratio(R/S) were calculated for 201 sample quadrats in the study area. We also studied the relationships between AGB and BGB of plants with the three different life forms(ephemeral, ephemeroid and annual). The mean AGB values of ephemeral, ephemeroid and annual plants were 0.806, 3.759 and 1.546 g/plant, respectively, and the mean BGB values were 0.106, 4.996 and 0.166 g/plant, respectively. The mean R/S value was significantly higher in ephemeroid plants(1.675) than in ephemeral(0.154) and annual(0.147) plants. The mean LMR was the highest in annual plants, followed by ephemeroid plants and ephemeral plants, reflecting the fact that annual plants allocate more biomass to leaves, associated with their longer life span. Biomass of ephemeral plants that germinated in autumn was significantly higher than those of corresponding plants that germinated in spring in terms of AGB, BGB and TB. However, the R/S value was similar in plants that germinated in autumn and spring. The slope of regression relationship between AGB and BGB differed significantly among the three plant life forms. These results support different biomass allocation hypotheses. Specifically, at the individual level, the AGB and BGB partitioning supports the allometric hypothesis for ephemeroid and annual plants and the isometric hypothesis for ephemeral plants.

Functional Enrichment of Utopian Distribution of Plant Life-Forms

Adaptive fuzzy neural inference systems are used to illustrate the primary nodal number of plant life-forms. Categorization of two candidate areas is carried out using the water-energy dynamic (for Ecuador, South America) and Macedonia, Southern Europe), within which the life-form spectra are distributed. Genetic optimization methods are used to expand the primary nodal number to the complete number of life-form categories. The distribution of the elements exhibits a stochastic, binomial distribution and the utopia line and curve are summarized which enhance accuracy of the climatic data and of the consequent numbers of plant species occurrences. Expansion of the distribution of each life-form category is approximated within the Z utopia hyperplane with use of the functional approximation algorithm. This process gives additional structure and informative value to the Z plane, enhancing our ability to make informed policy decisions concerning species and ecosystem conservation.

2011-2015年洞庭湖洲滩群落植物生态型、生活型和生长型组成数据集

植物群落结构与环境的关系可以通过研究植物生活型和生态型进行深入的解析,同时植物生活型是研究植物群落的发生、发展及演替规律的重要内容。中国科学院洞庭湖湿地生态系统观测研究站按中国生态系统研究网络(CERN)监测指标体系,在洞庭湖周期性水文变化情势下,对洞庭湖湿地洲滩典型植物群落类型的物种组成进行长期定位监测。通过专家对洞庭湖湿地3个典型植物群落(苔草、南荻和水蓼)的长期监测数据集进行验证,确保数据的准确性,然后进行分类处理,得到洞庭湖洲滩2011-2015年植物群落植物生活型、生长型和生态型数据集。本数据集包含有植物种名、拉丁名、生活型、生长型、光生态型、水分生态型、土壤pH值生态型、淤积生态型,共8个指标,同时提供了完整的样地信息和样地管理记录,为数据的科学利用提供了空间和时间上的背景信息。本数据集为分析洞庭湖湿地洲滩植被群落生态型和生活型组成,植物群落与环境的相关提供了数据支撑,是深入研究洞庭湖湿地植物被演替的重要参考依据。

中国省级重点保护野生植物的种类组成和多样性分析

为揭示我国省级重点保护野生植物的主要特征,对我国已公布省级重点保护野生植物名录的24个省份数据进行了整理,并初步分析其种类组成、生活型谱和濒危等级。结果显示:(1)我国省级重点保护野生植物共有2044种,隶属于208科,844属。其中,大型真菌有23种,苔藓植物有14种,石松类和蕨类植物有63种,裸子植物有50种,被子植物有1894种。不同省份的重点保护植物种数介于17~448种,平均种数为115种。(2)植物的生活型共有10种。其中以草本植物最多,有1200种,占总种数的58.71%;其次为常绿乔木,有262种,占总种数的12.82%;再次为落叶乔木,有225种,占总种数的11.01%。(3)根据世界自然保护联盟(IUCN)红色名录的濒危等级划分,这2044种植物可分为6种类型。其中以无危(LC)最多,有1224种,占比59.88%;其次为易危(VU),有248种,占比12.13%;再次为近危(NT),有198种,占比9.69%;濒危(EN)有173种,占比8.46%;极危(CR)有128种,占比6.26%。值得注意的是,濒危植物类群(包括CR、EN、VU、NT)的植物合计有747种,占比36.55%。研究发现,我国省级尺度的重点保护野生植物名录涵盖的植物类群广泛,但是各省制定的名录涉及的植物种数和比例差异很大。不同省份的重点保护野生植物的生活型多样,但是总体上以草本植物为主;这些植物的濒危等级相对较高,这可能与其地理分布相对狭窄、种群规模往往较小以及受到一定人为活动的影响有关。因此,建议国家及省级相关职能部门在省级尺度上对重点保护野生植物名录制定加强指导,在强调物种的珍稀、濒危和特有性的同时,更好地兼顾管理的可操作性、有效性和充分性。

明堂山主要药用植物资源调查分析

为全面了解岳西县明堂山药用植物资源的组成类型、生活型和药用部位等资源现状,本文采用传统野外调查方法收集药用植物资源的分布信息,通过形态观察及查阅相关文献资料对药用植物进行物种鉴定和药用植物整理分析.结果表明,本次调查发现药用植物231种,隶属96科205属,以小型科(2~4种)和单种科(1种)为主.生活型以草本植物占绝对优势(61.47%);药用部位以全草类、根及根茎类占多数(61.48%);珍稀濒危药用植物29种,其中国家一级保护植物2种,二级保护植物8种.岳西县明堂山药用植物资源类型多样性特征明显,生态环境保护良好,此次调查为后续有效保护和合理开发药用植物资源提供科学依据.

Impacts of snow on seed germination are independent of seed traits and plant ecological characteristics in a temperate desert of Central Asia

Seed germination profoundly impacts plant community composition within the plant life cycle.Snow is an important source of water for seed germination in the temperate deserts of Central Asia.Understanding how seed germination responds to variations in snow cover in relation to seed traits and plant ecological characteristics can help predict plant community sustainability and stability in Central Asia under a scenario climate change.This study investigated the seed germination of 35 plant species common to the Gurbantunggut Desert in Central Asia under the three snow treatments:(1)snow addition;(2)ambient snow;and(3)snow removal.Two-way analysis of variance(ANOVA)tests were performed to assess interactions among the impacts of snow treatments,seed traits and plant ecological characteristics on seed germination.Phylogenetic generalized least-squares(PGLS)model was used to test the relationships between seed traits and seed germination.The results demonstrated that snow variations had no significant impacts on seed germination overall.Seed germination under the snow addition treatment was similar with that under the ambient snow treatment,irrespective of seed traits and plant ecological characteristics.Snow removal only had negative impacts on seed germination for certain groups of seed traits and plant ecological characteristics.Seed mass positively affected seed germination,showing a linear increase of arcsin square root-transformed seed germination with log-transformed seed mass.Seed shape also profoundly impacted seed germination,with a higher germination percentage for elongated and flat seeds.Seed germination differed under different plant life forms,with semi-shrub species showing a significantly higher germination percentage.Most importantly,although snow treatments,seed traits and plant ecological characteristics had no interactive effects on seed germination overall,some negative impacts from the snow removal treatment were detected when seeds were categorized on the basis of seed mass and shape.This result suggests that variations of snow cover may change plant community composition in this temperate desert due to their impacts on seed germination.

塔里木盆地南缘绿洲-沙漠过渡带8种植物C、N、P生态化学计量特征的季节变化

研究荒漠生态系统中乔木、灌木和草本叶片生态化学计量特征及其随季节变化的规律,旨在阐明不同生活型植物生长发育过程中生态化学计量特征动态平衡及其差异,为荒漠生态系统的保护与管理提供理论依据。选择塔里木盆地南缘绿洲-沙漠过渡带内不同生活型8种植物,在生长季的4—9月连续进行叶片采集,分析叶片C、N、P含量及其计量比在整个生长季的变化。结果表明:(1)整体上,8种植物叶片C含量的季节变化不大,N、P含量在生长初期最高,之后逐步下降,体现了明显的稀释作用,而植物叶片的C∶N、C∶P和N∶P在整个生长季内的变化规律不一致;(2)综合分析8种植物叶片C、N、P含量及其计量比值在整个生长季节内的变异,变异系数由大到小排序为:P(32.39%)>C∶P(25.67%)>N(20.96%)>N∶P(20.42%)>C∶N(19.83%)>C(6.49%);(3)植物叶片C含量的变异主要受物种和生活型的影响,N、P含量及C∶N、C∶P的变异受物种和生长季的影响最大,而N∶P的变异受到生长季与物种的交互影响大于生长季的影响;(4)8种植物叶片N、P含量间存在极显著的正相关关系(P<0.001);P含量则与N∶P间呈现显著负相关(P<0.001),而N含量与N∶P间无显著相关性(P>0.05)。绿洲-沙漠过渡带8种植物叶片碳、氮、磷含量及其化学计量比在生长季因物种而不同,它们在生长季内的变异系数在物种间也存在差异,植物生长更容易受到N元素的限制。

桂林市訾洲公园植物资源调查研究

为了解桂林市訾州公园植物资源及景观现状,通过实地调查并查阅相关文献资料,对该公园植物组成、优势科、生活型、观赏特性、物种来源等进行分析。结果表明,园内共有维管束植物167种,隶属于74科145属,其中以豆科和禾本科为优势科;植物生活型齐全,乔木和草本占主体且常绿植物数量较多;观赏植物以观花植物为主,占植物总种数的57.5%;乡土植物97种,外来植物70种,占比分别为58.08%、41.92%;园内还有中国特有植物5种,濒危植物9种和国家重点保护植物7种。訾洲公园植物景观与其他构景要素较协调,地域特色鲜明,但仍需丰富藤本植物应用形式、增加观赏植物种类、加强宣传科普教育和采取合理的养护管理办法。以期为訾洲公园及桂林城市公园景观营建和升级改造提供参考。

大别山北缘不同生活型木本植物叶功能性状及其耦合关系

【目的】探讨大别山北缘不同生活型木本植物叶功能性状变异,研究叶功能性状指标之间的耦合关系,为解析植物对气候变化的响应机制提供依据。【方法】采集大别山北缘连康山国家级自然保护区30种常见的不同生活型木本植物(常绿、落叶、乔木、灌木)的叶片,测定其叶绿素含量(以SPAD表示)、干鲜比、氮质量分数、磷质量分数、钾质量分数、氮磷比、叶面积、比叶面积共8个叶功能性状指标,分析了不同生活型木本植物叶功能性状及其相关性。【结果】不同生活型木本植物叶功能性状指标具有一定的差异性,其中常绿和落叶树种的叶片SPAD、氮质量分数、磷质量分数、钾质量分数、叶面积和比叶面积之间差异显著(P<0.05);乔木与灌木树种的叶面积、氮质量分数、磷质量分数、钾质量分数、干鲜比与氮磷比差异显著(P<0.05)。部分叶功能性状指标之间存在一定的相关性,叶片氮、磷质量分数与钾质量分数呈显著正相关(P<0.05),叶片氮质量分数与磷质量分数呈显著正相关(P<0.05);叶面积与叶片氮、磷、钾质量分数呈显著正相关(P<0.05),比叶面积与叶片氮、磷、钾质量分数呈显著正相关(P<0.05)。主成分分析结果表明:叶片磷、氮、钾质量分数是较为重要的叶功能性状指示指标,可将30种木本植物归为4个功能组,且第1和第2主成分对植物叶功能性状变异的贡献率分别为55.2%和12.8%。【结论】叶功能性状指标在不同生活型木本植物之间存在一定差异,其中叶磷、氮、钾质量分数是指示性指标,且与叶面积显著正相关。图4表1参28.

大理苍山杜鹃花属植物资源及其种质资源圃建设分析

基于苍山科学考察资料及文献资料,对苍山杜鹃花属植物资源特征及种质资源圃建设条件进行分析。结果表明,苍山分布有杜鹃花属植物57种,占全国杜鹃花种数的9.5%,占云南省杜鹃花种数的14.3%;生活型以灌木型为主(73.6%),其次为灌木或乔木型(24.6%);分布海拔大于2 500 m的种数达44种,占苍山杜鹃花总种数的77.2%;苍山地区杜鹃花花色极其丰富,其中白色系种类最多(33.3%),其次为粉红色系(19.3%);杜鹃花花期为2—8月,主要集中于4—6月开放。从海拔、可建面积、水路条件等方面对苍山范围内具备建设杜鹃花种质资源圃的地块进行分析,结果认为,苍山花甸坝及大理大学茶园具有较好的建设条件。

河北茅荆坝自然保护区野生观赏植物资源调查与分析

通过田野调查和资料查询,对茅荆坝自然保护区野生观赏植物资源生活型进行调查统计。结果显示,该区域主要有58科123属149种审美价值较高的野生观赏植物。以此为基础,梳理归纳这些植物各自的生长类型、生态习性、分布状况、花(果)期、观赏部位、观赏特性和绿化用途等,分析其在保护开发中存在的被破坏、被取代、被淘汰等问题,提出保护优先、合理开发、适度利用,按难易程度递进开发利用,尊重生物多样性以及多层次开发、复合式利用等保护开发原则,为冀北地区和地理环境相近地区提供参考借鉴。

西北干旱区荒漠植物叶片和细根碳、氮、磷化学计量特征

植物的叶片和细根是植物地上部分和地下部分最重要的营养器官,其碳(C)、氮(N)、磷(P)化学计量特征反映了植物的养分限制状况及叶片与细根间的协同作用,开展叶片与细根化学计量关系的研究,对认识植物养分利用策略及元素间平衡关系有重要意义。对西北干旱区21种荒漠植物叶片与细根C、N、P含量进行了测定,分析了C、N、P含量及其计量比在不同生活型及不同器官间的关系。结果表明:1)西北干旱区荒漠植物叶片与细根C含量相对稳定,叶N、P含量高于细根,说明在干旱生境中,植物对养分的分配侧重于地上部分,以完成其正常的生命活动;叶片与细根的N∶P无显著差异,有明显的保守性,表明植物地上与地下部分养分吸收策略与分配规律具有一致性;2)不同生活型植物叶片和细根的C、N、P含量及C∶N、C∶P存在显著差异,灌木与禾草具有较高的C∶N和C∶P,杂类草具有较高的N、P含量,说明灌木与禾草倾向于保守型养分适应策略,杂类草倾向于快速生长的资源竞争策略;3)21种荒漠植物叶片与细根N、P含量间均存在显著的正相关关系,表明西北干旱区荒漠植物体内N、P元素间存在相互作用;4)植物叶片与细根间C、N、P含量及C∶N、C∶P存在等速生长关系,表明植物光合产物和养分在地上与地下部分间的分配具有平行的比例关系,但这种关系受生活型影响。上述结果表明西北干旱区不同生活型植物在恶劣生境中存在不同的养分适应策略,且地上与地下部分的养分利用策略及分配规律存在协同作用,这为进一步认识西北干旱区荒漠植物的养分利用策略提供了试验基础。

扬州市森林、湿地生态系统外来入侵植物调查分析与管理对策

通过线路踏查、资料分析,对扬州市森林、湿地生态系统外来入侵植物的种类组成、生活型、繁殖方式、原产地、入侵方式、生态系统类型及分布进行了研究。结果表明:扬州市外来入侵植物共有18种,隶属于9科15属,其中菊科种类最多(9种),占比50.00%;调查到的外来入侵植物均为草本植物,以一二年生草本植物最多(10种),占比55.56%;这些草本植物大多均依靠种子繁殖,仅有空心莲子草、大薸和凤眼蓝3种水生草本植物依靠营养繁殖;按原产地统计来看,原产于美洲的植物种类最多(15种),占83.33%;有50.00%(9种)入侵植物属于有意引入,44.44%(8种)属于无意引入,自然传入的仅有豚草1种。按生态系统来看,乔木林地和灌木林地中的外来入侵植物种类最多,有15和13种。就扬州市外来入侵植物发生情况进行了讨论分析,并提出相应的管理对策。

麦秀国家森林公园植物种类组成及区系研究

为了解麦秀国家森林公园植物的分布及种类多样性,采用野外采集植物和文献分析相结合方法,分析了麦秀国家森林公园植物区系的基本特点。结果表明:(1)植物种类丰富,维管植物68科290属744种,其中蕨类植物7科11属21种,裸子植物3科4属9种,被子植物58科275属714种。(2)植物生活型多样,乔木28种,灌木61种,半灌木4种,草本645种,藤本6种;草本植物占绝对优势。(3)植物以小科所占比例最大,占总科数的32.35%。(4)在科的地理分布上,划分为5个类型5个变型,其中世界分布的科较多,占总科数的54.10%。(5)在属的地理分布上,北温带分布最为广泛,占总属数的1/3;世界分布、旧世界温带分布、北温带和南温带(全温带)间断分布的属数量也较多,在总属数中的比例都超过了10.00%;中国特有属9个。

兴安盟地区常见野生植物种质资源及其生活型特征

【目的】调查分析兴安盟地区常见野生植物种质资源分布情况及其生活型特征,为野生植物资源的保护与合理开发利用提供参考。【方法】以兴安盟为研究区,采用实地踏查法结合室内分类鉴定,调查分析该区域常见野生植物种质资源的地理分布范围、生境特点、种类及其生活型特征。【结果】在兴安盟地区共收集到常见野生植物种质资源240份,不重复物种173个,分属40科、121属。其中,多年生禾草种质资源47份,灌木、亚灌木及小乔木26份,多年生杂类草115份,1~2年生草本植物52份。以多年生杂类草种子最多,占收集种子总数的46.96%,其次为1~2年生草本植物种子,占比为21.67%;多年生禾草和灌木、亚灌木、小乔木种子较少,占比分别为19.58%和10.83%。【结论】从地理分布范围看,多年生禾草主要分布在乌兰浩特市,灌木、亚灌木与小乔木主要分布在扎赉特旗与阿尔山市,多年生杂类草和1~2年生草本植物主要分布在扎赉特旗、阿尔山市、科尔沁右翼前旗与中旗。

两种生活型木本植物叶功能性状变异特征研究

以乔木和灌木两种生活型木本植物为研究对象,研究其植物叶性状及其变异特征,揭示两种生活型木本植物的适应机理。以新乡市16种木本植物:刺槐(Robinia pseudoacacia)、五角枫(Acer elegantulum)、加拿大杨(Populus×ca⁃nadensis)、毛白杨(Populus tomentosa)、法桐(Platanus orientalis)、白蜡(Fraxinus chinensis)、玉兰(Magnolia denudata)、银杏(Ginkgo biloba)、栾树(Koelreuteria paniculata)、日本晚樱(Cerasus serrulata)、紫荆(Cercis chinensis)、紫叶李(Prunus cerasifera)、垂丝海棠(Malus Halliana)、西府海棠(Malus micromalus)、榆叶梅(Amygdalus triloba)和丁香(Syzygium aromaticum)为试材,对其叶面积(leaf area,LA)、叶厚度(leaf thickness,LT)、叶干物质含量(leaf dry matter content,LDMC)、比叶面积(specific leaf area,SLA)、叶鲜重(fresh leaf weight,FW)、叶干重(dry leaf weight,DW)、叶绿素含量(chlorophyll,Chl)和叶含水率(leaf moisture content,LWC)这8种叶功能性状进行测定和分析。结果表明:8种叶性状存在不同程度的变异。乔木树种的叶鲜重(90.13%)、叶干重(86.36%)和叶面积(95.13%)呈强变异,叶干物质含量(18.79%)和叶含水率(12.81%)属于弱变异;灌木树种的比叶面积(54.03%)、叶鲜重(60.17%)和叶面积(62.17%)属于强变异;叶含水率(14.60%)属于弱变异。叶功能性状间关系密切,乔木树种的叶面积与叶鲜重和叶干重呈极显著正相关关系(p<0.01),与比叶面积呈显著正相关关系(p<0.05);灌木树种的叶面积与叶鲜重、叶干重、比叶面积和叶含水率都呈极显著正相关关系(p<0.01),与叶干物质含量呈极显著负相关关系(p<0.01)。主成分分析显示,8种叶功能性状指标中,叶鲜重、叶干重、叶绿素含量贡献率最大,可作为木本植物适应生境的重要指标。总体来说,乔木树种的大多叶功能性状的稳定性和性状间的相关性与灌木植物相比较弱,乔木树种为适应生态环境,在生存机制上做出的调整程度大于灌木树种。

鸭绿江口湿地外来入侵植物区系、生活型及种类特征

【目的】鸭绿江口湿地沿边沿海,生物入侵形势严峻,本文旨在探究其外来入侵植物特征的基本信息,为我国北方滨海湿地入侵植物防控提供支持和参考。【方法】基于植物地理学理论和外业实地踏查法,同时结合文献查阅和咨询法,研究鸭绿江口湿地外来入侵植物区系、生活型和种类特征。【结果】鸭绿江口湿地外来入侵植物共有33种,隶属11科26属,其中菊科、豆科和苋科是入侵植物的优势科,占总种数的57.57%;植物科的区系以世界分布型为主,属的区系以泛热带、世界分布型占主导地位;原产于美洲的种类最多,占总种数的51.52%;生长型以草本植物为主,占总种数的90.91%;生活型以地面芽和一年生植物种数最多,占总种数的87.87%;果实以瘦果类型居多,占总种数的27.27%;扩散方式以混合传播和风力传播为主,占63.63%;湿地内入侵植物危害等级以恶性入侵(Ⅰ级)和严重入侵种(Ⅱ级)为主,占总种数的39.4%。【结论】鸭绿江口湿地外来入侵植物种类以菊科、豆科和苋科为主;原产美洲最多,以草本植物为主,混合传播和风力传播占优,危害严重的种类多。应加强入侵植物监测和预警,并结合河口、海岸等生境治理,采取相应措施予以防除。

土壤起源与宜居地球的形成

在各种成土因素交互作用下,地球土壤起源和演变历经变化的环境和多种成土过程。研究表明最早的古风化壳出现在太古宙;而随着地球生物演进,生物因素加入风化成土作用与成土过程,土壤学家眼中的土壤形成、发育于寒武纪。漫长的地质历史时期不同的成土环境发育有各种类型土壤,这些土壤发育与演化过程又反作用于景观、地形、生态系统、气候系统,改变大气成分组成和地球化学循环,影响、反馈、调节全球或地区的表层系统,土壤圈的形成是宜居地球形成的重要标志。