Study on Sonneratia apetala productivity in restored forests in Leizhou Peninsula, China

The exotic Sonneratia apetala in Leizhou Peninsula, has shown outstanding fast-growing ability in restored mangrove forests, at the middle and high tide intertidal zone, with year-round fresh water input from drainage. By setting plot and selecting standard tree, investigation and measurement on height growth, diameter growth, biomass, productivity, and so on, were made in a S. apetala plantation at age of six at Lanbei, Fucheng, Leizhou Peninsula in May 2001. The investigating results showed that the mean annual height growth of plantation was 2.03 m and mean annual growth of diameter at breast height (DBH) was 2.35 cm. There exists a significant correlation between the diameter at ground surface (DGS) and DBH. The average biomass of a single standard tree in dry weight was 95.647 kg/m2. A ratio of above-ground biomass to under-ground biomass was 1.60. The stand biomass of unit area was 22.955 kg/m2, singletree wood volume was 88.23 dm3, and the annual wood volume productivity (PA) of the same year was 0.407. The forest energy accumulation was 424.851 MJ/m2, with annual solar energy fixing rate of 40.68 ×10-7%. It is concluded that S. apetala species had characteristics of outstanding high biomass accumulation and could be used as coastal planting tree species in southern China.

秋茄(Kandelia obovata)和无瓣海桑(Sonneratia apetala)红树人工林消波效应量化研究

采用野外监测的方法对海南东寨港三江湾秋茄和无瓣海桑红树人工林的消波效应进行了量化研究。结果表明,裸露海滩的消波作用较弱,波浪在经过裸滩50m后,1/10波高、1/3波高和平均波高分别减低2.9%、4.4%和5.8%。红树林的消波作用显著,总体来说,波浪在经过秋茄林50m后,1/10波高、1/3波高和平均波高分别减低46.3%、46.4%和46.1%,在经过无瓣海桑林50m后分别减低30.1%、29.6%和28.8%。红树林的消波率随林分基部断面积的增大而增加;在浅水区域,红树林的消波率随水深增加而降低;在水深相同的条件下,红树林的消波效应随着波高的增加而增强;红树林的消波率与波浪的传播距离呈非线性正相关性,随着传播距离的增加,波高持续降低,但降幅减小。

华南沿海基围渔塘内无瓣海桑Sonneratia apetala的生长效应

在华南沿海基围渔塘内人工控水条件下进行了红树植物无瓣海桑的人工恢复试验,结果表明:(1)基围内不同控水滩血高程对红树植物无瓣海桑的生长量和成活率有显著影响,随着滩面控水高程的增加,无瓣海桑的生长量与成活率有降低的趋势;(2)基围内种植密度对无瓣海桑的生长有显著的影响:在一定的控水滩面高程下,种植密度越大,生长越差;(3)种植季节对无瓣海桑种植初期的生长影响显著,较冷季节时种植不利于无瓣海桑的成活和生长;(4)在一定的条件下,种植20个月后基围内、外无瓣海桑的生长和成活情况基本接近,差异较小;(5)在基围渔塘内,大米草对红树植物无瓣海桑种植后的初期生长有一定的抑制作用。研究结果可以为华南沿海大面积的基围渔塘内红树林的生态恢复提供一定的理论参考。

福建不同地区人工引种无瓣海桑(Sonneratia apetala)生理生态研究

采用乙醇提取法、纳氏比色法、钼锑抗显色法及F-C法分别研究了人工引种于福建省漳浦、集美、泉港、连江无瓣海桑(Sonneratia apetala)成熟叶片的生理指标:叶绿素、氮、磷及总酚含量。结果表明,4个地区叶片叶绿素a含量在(1.44±0.54)—(2.52±0.94)mg/g之间波动,叶绿素b含量范围在(0.54±0.02)—(0.94±0.11)mg/g之间,叶绿素a/b随着纬度的升高有增大趋势,表明随纬度升高无瓣海桑对蓝紫光需求比例增大;各地点无瓣海桑氮、磷含量均无显著差异,且N:P比值均小于14,表明均存在N限制;总酚含量随着纬度的升高而逐步升高,可能与无瓣海桑生长条件随纬度的上升而受到外界环境胁迫增大有关。

Ecological influence of exotic plants of Sonneratia apetala on understory macrofauna

The study aims to compare the differences of macrofauna communities of wetlands at 3-year-forest- age, 5-year-forest-age Sonneratia apetala artificial mangroves, 5-year-forest-age Kandelia candel ar- tificial mangroves with the same restoration background, and the naked tidal flat in the Qi’ao Island Mangrove Nature Reserve of Zhuhai, Guangdong Province. The results show that there were signif- icant structural differences in macrofauna communities among four kinds of habitats. The increase of biomass and species diversity of macrofauna at 3-year-forest-age S. apetala artificial mangroves was obviously faster than that at 5-year-forest-age K. candel artificial mangroves whose average tree height was close to that of 3-year-forest-age S. apetala artificial mangroves. The BIOENV analysis shows that it was related to the rapid growth of S. apetala, which rapidly changed the light level and shading conditions in the forests. The 5-year-forest-age S. apetala artificial mangroves had lower macrofauna species diversity but higher density and biomass than K. candel artificial mangroves with the same forest age. This was due to the rapid changes of physical and chemical properties of habitat soil by the ecological restoration of S. apetala artificial mangroves as well as the changed food sources possibly caused by the leaf-litter of such non-indigenous mangrove species S. apetala. However, further survey should be conducted on whether there are any negative ecological impacts of large-scale cultivation of S. apetala on macrofauna communities, so as to evaluate correctly S. apetala’s role in the restoration of coastal mangrove ecosystems.

Ecological indicators showing the succession of macrofauna communities in Sonneratia apetala artificial mangrove wetlands on Qi'ao Island at Zhuhai, South China

The Sonneratia apetala artificial mangroves in the intertidal zone of Da Wei Bay at Qi’ao Island of Zhu-hai, South China were chosen as the macrofauna succession plots while bare tidal flats of the same size were established as control plots in surrounding interference-free areas. Conventional change indicators of community structure, such as biomass and biodiversity, and indicators, such as exergy and specific exergy, which reflect the information change of overall communities, were used to analyze the succession of macro-fauna communities inS. apetala artificial mangroves. The similarities and differences in variation tendency of the different ecological indicators and their reflected ecological principles were compared. The results showed that from D-1 to D-1275 after plantingS. apetala, the biomass of the macrofauna communities first increased, which was then followed by an increase in the network relationship between the macrofauna communities （analysis of the Pielou evenness index and Shannon-Wiener diversity index）. The system in-formation （specific exergy） increased the slowest. Between D-1460 and D-2370 after plantingS. apetala, there was a decrease in biomass, network structure, and system information in the succession plots. After the decrease in the system information （the specific exergy）, there was a decline in the network relationships （Pielou evenness index and Shannon-Wiener diversity index）. Biomass was the last indicator to decrease. The similarities and differences among the different ecological indicators varied during the succession pro-cess, which reflected the relativity and differences among the indicators. This study suggested that, although the species diversity index can be an effective indicator of two types of changes （network structure and system information）, it was quite clear that species diversity measurement was not suitable for expressing the changes in biomass during the succession process. While exergy and specific exergy can provide useful information about the structural development of communities, they cannot identify the information state of the system. Therefore, when evaluating macrofaunal succession inS. apetala artificial mangrove wetlands, it would be better to apply a number of different ecological indicators, rather than just one single indicator.

Accumulation and Cycle of Heavy Metals in Sonneratia apetala and S. caseolaris Mangrove Community at Futian of Shenzhen, China

This paper reports the absorption, accumulation, distribution and cycle of Cu, Pb, Zn, Cr and Ni in S. apetala + S. caseolaris, mangrove community at Futian Mangrove Nature Reserve of Shenzhen. The Cu, Pb, Zn, Cr and Ni contents in forest soil increase from bottom to surface layers, and the storage of the five heavy metals in the surface layer (depth 0 ~ 30 cm) is Zn > Pb > Ni > Cr > Cu. The concentration ability is S. caseolaris > S. apetala > K. candel. The existing accumulation of Cu, Pb, Zn, Cr and Ni in the community μis 23 019.63g/m2μ, 23 429.66g/m2μ, 117 870.42g/m2μ, 6 835.80g/m2μ, and 12 995.22g/m2μ, respectively. The annual absorption is 6 592.57g/m2μ, 2 664.80g/m2μ, 23 123.56g/m2μ, 853.24g/m2μ, and 1 990.95g/m2, respectively. The annual return is μ3 179.50g/m2μ, 1 300.65g/m2μ, 7 401.31g/m2μ, 398.99g/m2μ, and 646.20g/m2, respectively. The annual net retention accumulation of Cu, Pb, Zn, Cr and Ni in the community is 3 413.07μg/m2, 1 364.15μ g/m2, 15 722.25μg/m2, 454.25μg/m2, and μ1 344.75g/m2, respectively. The turn over periods of Cu, Pb, Zn, Cr and Ni are 8,19,15,18 and 21 years, respectively.

珠江口无瓣海桑(Sonneratia apetala)湿地中浮游动物构成及富营养化评价

选择珠江口南沙区两处典型的以大面积人工种植红树植物无瓣海桑(Sonneratia apetala)为主的感潮河涌,进行湿地区域中的浮游动物研究。于2011年5月和11月对开放性河涌湿地14涌(A区)和封闭性河涌湿地19涌(B区)中的浮游动物进行调研,从种类数和丰度、污染指示种和优势种、营养指数E和污染指数A等方面对浮游动物进行群落结构和功能的分析,并以此对湿地水质和无瓣海桑的净化能力进行评价。结果表明,B区林内原生动物总丰度可达106ind/L数量级,7种丰度优势种均为纤毛虫类,优势种哑铃中缢虫(Mesodinium rubrum),1种赤潮原生动物种类,单种丰度在春秋两季可达1.8×105ind/L、5.1×105ind/L。桡足类、枝角类在春季B区林内丰度最高,分别可达576ind/L和46ind/L,显示春季可能为其繁殖季节。轮虫相对不耐污染生境。指数E和指数A均远高于判断阈值。提出了二项浮游动物的富营养判断标准和二条原则。据此判断,B区湿地存在极重的有机污染现象,主要可能与无瓣海桑林内凋落物量较大或根系分泌物的作用且林内水流不畅有关。

Antimicrobial activity of kojic acid from endophytic fungus Colletotrichum gloeosporioides isolated from Sonneratia apetala,a mangrove plant of the Sundarbans

Objective: To isolate and evaluate the antimicrobial activity of the active principle(s) from the ethyl acetate(EtOAc) extract of endophytic fungus Colietotrichum gloeosporioides(C.gloeosporioides) isolated from Sonneratia apetala. Methods: Water agar technique was used to isolate the fungus, and both microscopic and molecular techniques were used for identification of the strain. Potato dextrose broth was used to grow the fungus in large-scale. Reversed-phase preparative HPLC analysis was performed to isolate the major active compound, kojic acid. The EtOAc extract and kojic acid were screened for their antimicrobial activity against two Grampositive and two Gram-negative bacteria as well as a fungal strain using the resazurin 96-well microtitre plate antimicrobial assay. Results: The fungus C. gloeosporioides was isolated from the leaves of Sonneratia apetala. Initial identification of the fugal isolate was carried out using spore characteristics observed under the microscope. Subsequently, the ITS1-5.8 S-ITS2 sequencing was employed for species-level identification of the fungus C. gloeosporioides. Five litres of liquid culture of the fungus produced approximately 610 mg of a mixture of secondary metabolites.Kojic acid(1) was isolated as the main secondary metabolite present in the fungal extract, and the structure was confirmed by 1 D, 2 D NMR and mass spectrometry. The EtOAc extract and compound 1 exhibited considerable antimicrobial activity against all tested microorganisms.Whilst the minimum inhibitory concentration(MIC) values from the EtOAc extract ranged between 2.4×10^(-4)mg/mL and 2.5 mg/mL, those of kojic acid(1) were between 0.125 mg/mL and1 mg/mL. The EtOAc extract and kojic acid(1) were most active against Pseudomonas aeruginosa(MIC = 2.4×10^(-4). mg/mL) and Micrococcus luteus(MIC = 0.125 mg/mL), respectively. Conclusions:The results revealed that the endophytic fungus C. gloeosporioides could be a good source of commercially important kojic acid, which exhibited antimicrobial properties.

Indoor Control Efficacy of 4 Kinds of Pesticides against Latoia pastorlis (Butler) in Sonneratia apetala Buch-Ham

[Objective]The paper was to screen pesticide that could effectively control Latoia pastorlis （Butler）, and provide reference for its utilization in fields. [Method]The indoor control efficacy of 25% benzoylphenal urea, 30% trichlorfon, 16 000 IU/mg Bacillus thuringiensis and Beauveria bassiana on 2-3 instars larvae of L. pastorlis were determined, and the indoor toxicity of 25% benzoylphenal urea and crystal trichlorfon on shrimp was also tested. [Result]Four pesticides all had insecticidal effects on 2-3 instars larvae of L. pastorlis, of which 30% trichlorfon 800, 1 000 and 1 500 times and 25% benzoylphenal urea 800 times had the best control effect. Crystal trichlorfon with the concentrations of 0.500, 0.100, 0.010 mg/L and 25% benzoylphenal urea 8 000, 10 000, 15 000 times had little or no impact on shrimp, respectively.[Conclusion] 30% Trichlorfon was rapidly available with small impact on shrimp, which were suitable for emergency use or daily control of L. pastorlis. 25% Benzoylphenal urea and 16 000 IU/mg B. thuringiensis had relatively slow insecticidal effect, which was suitable for daily control of L. pastorlis.

Biological Characteristics of Trabala vishnou Lefebure in Sonneratia apetala Buch-Ham

[Objective]The paper was to understand the biological characteristics of Trabala vishnou Lefebure. [Method]Using the combination methods of field survey, caged observation in forest and indoor rearing observation, the morphological characteristics, biological characteristics and natural enemies of T. vishnou in Qinzhou Kangxiling Mangrove Natural Reserve in Guangxi Province were investigated.[Result]T. vishnou occurred for 4- 5 generations each year in Qinzhou Mangrove Nature Reserve of Guangxi, the developmental duration of each generation averagely was 57.64 d. The pest survived the winter as eggs, mature larvae or pupae, and the overwintering eggs, mature larvae and pupae began to occur in December.[Conclusion]The study provided a scientific theoretical foundation for the prediction and control of T. vishnou.

无瓣海桑(Sonneratia apetala)对浮游微藻群落结构及生态功能的影响研究

2009年春季和秋季对广州市南沙区14涌和19涌以人工种植红树植物无瓣海桑(Sonneratia apetala)为主的湿地水体中的浮游微藻进行采样调查,从种类数、丰度、门类组成和多样性指数对微藻进行群落结构及其生态功能的分析研究,并以此对湿地水质进行评价和从藻类的角度分析无瓣海桑对湿地水体的净化功能。结果显示,微藻种类极其丰富,共鉴定出8门92属338种,总丰度在105～107个/L数量级,其中以19涌湿地公园无瓣海桑林内微藻丰度最高,达9.45×106～1.20×107个/L,为超富营养水平。14涌和19涌都存在着有机污染现象,但14涌湿地水质要优于19涌,主要与其内水文条件较优有关。无瓣海桑如果在较封闭的水体环境中易产生较严重的水体富营养化现象。在管理人工红树林湿地时应注意保证林内与林外水体的流通。

Ecological Assessment on the Introduced Sonneratia caseolaris and S. apetala at the Mangrove Forest of Shenzhen Bay, China

yTwo exotic species, Sonneratia caseolaris (L.) Engl. and S. apetala B. Ham., were introduced to Futian Mangrove Forest Nature Reserve, Shenzhen Bay, in 1993 for afforestation. Winter cold caused frigid harm but did not appear to be an obstacle to the introduction. The cold tolerance of the parental and filial generation increased in several years. The two Sonneratia spp. could propagate by seeds and disperse in Shenzhen Bay. While the two species grew faster than indigenous species, at the same time they promoted the growth of indigenous species, but they could not replace indigenous mangrove species. Suitable habitat was more important than the distance from the source in the natural spreading for the two species. The niche of the two species did not overlap with the niche of indigenous species. The two species did not self regenerate, although they could disperse on localized area in Shenzhen Bay. Therefore, it was unlikely that the two species would pose ecological disaster.

Phytochemical Profiling and Bioactivity of A Mangrove Plant,Sonneratia apetala,from Odisha Coast of India

Objective： To test the antioxidant, antidiabetic, anticancer and antibacterial activities along with phytochemicals of Sonneratia apetala Buch.-Ham. Methods： The antibacterial activity was determined by agar well diffusion method. The antioxidant activity was determined by standard assay. The antidiabetic activity was evaluated by α-glucosidase inhibition assay and in vivo anticancer property was determined against Ehrlich ascites carcinoma （EAC） cells in Swiss Albino mice. Further partial characterization of the methanol extracts was carried out by thin layer chromatography, high performance liquid chromatography, 1H nuclear magnetic resonance spectroscopy and Fourier transform-infra red spectrum spectral analysis. Results： Four solvent extracts （acetone, ethanol, methanol and aqueous） of leaf and bark possess strong antioxidant properties. In vivo anticancer activity of methanol extract leaf indicated positive activity showing 34% inhibition against EAC cells in Swiss Albino mice. All extracts exhibited a-glucosidase inhibitory activity in a dose-dependent manner indicating presence of promising antidiabetic properties. The extracts possess strong antibacterial activity against the selected pathogenic bacteria （minimal inhibitory concentration ranging from 1.25-5.00 mg/mL）. The partial characterization of the methanol extracts of leaf and bark revealed the presence of phenolics as the lead compound responsible for studied bioactivities of the plant extracts. Conclusion： Sonneratia apetala extracts have potent antibacterial, antioxidant, antidiabetic and anticancer properties which can be further exploited for its pharmaceutical applications.

厦门下潭尾红树“实验林”研究成果分析和启示

为了研究林鹏院士2005年在厦门市下潭尾开展的红树林“实验林”对厦门市红树林红树林生态修复工作的指导作用,本研究分析了该“实验林”的乡土种秋茄(Kandelia obovata)和引进种无瓣海桑(Sonneratia apetala)生态恢复影响、乡土种与引进种不同搭配种植模式的生态效果,以及其各阶段植被演变的状况。结果表明,无瓣海桑在厦门海域扩散能力差,未见生态入侵的危害,并有逐渐生态归化趋势;通过加强监控、扬长避短,因地制宜、分区施策、适地适树,合理规划,可以充分发挥外来植物的正面作用。

外来红树无瓣海桑在广东省的空间分布研究

外来红树无瓣海桑Sonneratia apetala是我国红树林造林的重要树种,具有耐水浸、生长速度快、适应性强等特点。随着无瓣海桑的自然更新与扩张,其入侵风险引起社会广泛关注。为准确获取无瓣海桑分布,加强对这一外来树种的跟踪检测,研究基于Sentinel-2卫星影像和随机森林算法,在Google Earth Engine平台下构建了2015年广东省无瓣海桑分布数据,总体精度达到96.3%。结果表明:2015年广东省无瓣海桑总面积为1704.33 hm^(2)。应用核密度分析方法发现,这一外来红树主要集中在雷州半岛西部和珠江口区域。与2020年的数据对比显示,广东省无瓣海桑的斑块数量和斑块面积均有较为显著的扩张。

钦州湾不同林龄无瓣海桑人工林表层沉积物生态化学计量特征

【目的】生态化学计量学是探索耦合元素平衡和循环的有效工具,研究无瓣海桑人工林表层沉积物关键元素含量及其生态化学计量特征,为外来植物科学管控提供理论依据。【方法】以钦州湾滨海湿地3块不同林龄(10、15和20 a)的无瓣海桑人工林为研究对象,每个林分设置3块20 m×20 m的样地,每块样地内采用蛇形布点法采集0~20 cm表层沉积物样品,测定样品的有机碳(TOC)、全氮(TN)、全磷(TP)、有效磷(AP)、全硫(TS)、有效硫(AS)、全钾(TK)、有效钾(AK)等含量,研究表层沉积物C、N、P等元素生态化学计量特征及其影响因素。【结果】1)无瓣海桑林龄对沉积物TOC、TN、TP、TS、AS等理化性质及C/N、C/P、C/S、C/K、N/S、P/S、P/K、S/K等生态化学计量具有显著影响;2)研究区沉积物C/N均值(20.41)略高于中国湿地土壤C/N均值(18.22),C/P均值(64.91)、N/P均值(3.19)远低于中国湿地土壤C/P均值(245.22)、N/P均值(13.6),C∶N∶P均值为20.3,处于中国湿地土壤中C∶N∶P变化范围7.08~41.44之间;3)相关性分析与冗余分析结果表明,TOC、TN和TP是影响沉积物生态化学计量变化的关键因子。【结论】研究区沉积物具有富C、P而少N的特点,沉积物P素矿化能力较强,无瓣海桑生长需P量大、受N限制。在无瓣海桑人工林管理过程中,建议科学调控沉积物TOC含量、降低入海口N素和P素输入来减缓无瓣海桑的扩散速度,以降低其生态风险。

不同林龄和潮位无瓣海桑生态系统碳储量差异

为探究林龄和潮位对无瓣海桑Sonneratia apetala生态系统碳储量的影响,文章以广东省珠海市淇澳岛自然保护区的无瓣海桑人工林为研究对象,选择滩涂、高潮位无瓣海桑林(2002年种植,18 a)、低潮位无瓣海桑林(2002年种植,18 a)、低潮位无瓣海桑林(2008年种植,12 a),分别测定生物量和0~100 cm土层土壤的有机碳含量、氮磷硫含量、微生物碳含量,以及理化因子如pH、盐度、容重。结果表明,18 a低潮位无瓣海桑植物生物量((297.06±18.92)Mg·hm^(-2))、土壤碳储量((184.97±2.45)Mg·hm^(-2))和生态系统碳储量((312.77±10.59)Mg·hm^(-2))均显著高于12 a低潮位无瓣海桑(分别为(210.68±4.80)、(137.86±10.31)和(228.49±12.37)Mg·hm^(-2),P<0.05),林龄的增加显著提高了植物生物量以及土壤碳氮比,表明红树林源碳对土壤碳的贡献比例明显增大。18 a高潮位无瓣海桑的生态系统碳储量(347.66±39.46 Mg·hm^(-2))显著高于18 a低潮位无瓣海桑(P<0.05),可能是因为高潮位无瓣海桑林经受低强度的潮汐作用以及较弱的微生物分解作用。因此,林龄和潮位对生态系统碳储量均有显著性影响,而无瓣海桑因其较低的碳氮比,可能会不利于土壤碳的累积,同时因无瓣海桑具有潜在的入侵风险,不适宜作为本土红树林退化区生态修复的工具种。

无瓣海桑炭疽病病原菌鉴定及其生物学特性分析

为明确无瓣海桑炭疽病的病原菌种类,为该病害的有效防控提供基本依据,采集无瓣海桑Sonneratia apetala受害叶片,通过组织分离法获得菌株,利用柯赫氏法则确定病原菌;利用形态学及分子生物学分析方法明确病原菌的分类地位,同时开展生物学特性分析。通过接种试验确定,从病组织中分离获得菌株WBHS-YK-1为无瓣海桑炭疽病的病原菌。该菌在PDA上培养7 d,菌落圆形,气生菌丝白色,培养基底部有青黑色色素沉淀,同时产生黄色的分生孢子堆;分生孢子呈长椭圆,无色,无隔膜,孢子大小为(15~19)μm×(6~8)μm。基于ITS序列构建的系统发育树显示:该菌株与菌种Colletotrichum fructicola聚在同一分支,支持率高达98%,表明该菌与C.fructicola具有较高的亲缘关系。结合形态学特征,最终确定菌株WBHS-YK-1为果生炭疽菌C.fructicola。该菌能最佳碳源为葡萄糖,最佳氮源为蛋白胨;最适培养温度为30℃,最适pH为7~8。

不同林龄无瓣海桑人工林土壤生态化学计量特征

为探究不同林龄无瓣海桑林土壤养分及其生态化学计量特征变化,通过测定10,15,22 a共3个林龄无瓣海桑林0~30 cm土层土壤的pH值、含盐量(TDS)、有机碳(SOC)、全氮(TN)、碱解氮(AN)、全磷(TP)、有效磷(AP)、全钾(TK)和速效钾(AK)含量,计算化学计量比,并分析各指标间的相关性。结果表明:1)造林后,土壤pH值表现为先上升后下降,土壤养分明显增加,土壤SOC,TN含量高于全国土壤平均水平,TP含量略低于全国土壤平均水平;2)不同林龄土壤理化性质及生态化学计量比均存在显著差异,随林龄的增加,土壤pH值先增加后降低,SOC,TN,AN,TP和AK含量先降低后增加,TK和AP变化不明显;3)无瓣海桑林的生长发育可能受到氮(N)的限制,尤其是林龄幼中期影响较大。无瓣海桑人工林对红树林湿地土壤养分的恢复具有明显的调节作用。