恢复初期红树林树栖滨螺科动物的组成与分布

滨螺科动物是红树林中常见的底栖动物,它们的形态、行为和分布等与红树林植被密切相关。本文调查了植被恢复初期(3年生)红树林树栖滨螺科动物的组成和分布情况,并探讨滩涂高程和树种对滨螺科动物分布的影响。结果表明:植被恢复初期滨螺科物种已成为优势类群,密度达到32.67 ind·m~(-2);黑口滨螺在不同滩涂高程下均为优势种,其密度和生物量在黄零1.8 m高程的秋茄林内较其他林地(黄零2.2和2.6 m)高;粗糙滨螺仅出现在黄零1.8 m的秋茄林内;种植于黄零1.6 m高程的桐花树林内黑口滨螺的生物量和密度均大于同样高程下的秋茄林,但桐花树林内的个体小于秋茄林内的个体;粗糙滨螺在不同树种间的分布没有明显差异;滨螺科物种的分布在红树林恢复初期随生境的异质性表现出差异,这种差异可能与植被形态导致的物理环境差异以及滨螺科物种活动习性、繁殖扩散模式等生物学特性有关。     

广东湛江红树林保护区大型底栖动物群落的空间分带

用生态样带研究了广东湛江红树林保护区高桥镇核心区大型底栖动物的空间分带。结果表明：德耀村红树剖面中出现的大型底栖动物优势种类为琵琶拟沼螺、悦目大眼蟹、扁平拟闭口蟹、宽身闭口蟹、黑口滨螺、等齿角沙蚕、弧边招潮和中华伪露齿螺。该剖面大型底栖动物从高潮位到低潮位可分为3个分布带：琵琶拟沼螺-弧边招潮-浓毛拟闭口蟹带；宽身闭口蟹．悦目大眼蟹．黑口滨螺带；扁平拟闭口蟹-珠带拟蟹手螺带。群落生物量的变化主要由软体动物所主导，栖息密度的变化主要由软体动物和甲壳动物所主导，多样性指数变化主要由软体动物所主导。红寨村红树剖面中出现的大型底栖动物优势种类为琵琶拟沼螺、蝼姑虾、扁平拟闭口蟹、宽身闭口蟹、耳螺科的一种、黑口滨螺、中华伪露齿螺、哈氏仿对虾、弧边招潮和等齿角沙蚕。该剖面大型底栖动物也可分为4个分布带：黑口滨螺-中华伪露齿螺-等齿角沙蚕带；琵琶拟沼螺-宽身闭口蟹-耳螺科的一种带；蝼蛄虾．扁平拟闭口蟹带；沈氏长方蟹-珠带拟蟹守螺带。群落生物量的变化也主要由软体动物所主导，栖息密度的变化主要由甲壳动物所主导，多样性指数变化主要由软体动物所主导。底栖动物群落的等级聚类和非参数多变量标序显示，大型底栖动物分带与红树植物群落类型相一致。大型底栖动物分带受红树植物群落类型影响的主要原因是不同红树植物群落间的群落特征、沉积物性质和所处潮位线存在差异。     

异速生长法计算秋茄红树林生物量

采用异速生长方法,建立树干基部多分枝型秋茄生物量与分枝直径的函数模型,根据该模型计算了浙江鳌江河口人工秋茄林生物量,并比较了我国不同地区秋茄林生物量差异。结果表明,秋茄生物量(W)与分枝直径(D)之间存在极显著的回归关系,叶片(WL)、树干(WS)、根系和分枝基部(WB)及植株总生物量(WT)与分枝直径(D)的异速生长方程分别为:WL=0.187D1.855(R2=0.612,P<0.0001);WS=0.267D1.906(R2=0.821,P<0.0001);WB=4.6D1.136(R2=0.644,P<0.0001);WT=3.614D1.446(R2=0.801,P<0.0001)。我国不同地区秋茄林地上生物量与林龄和纬度之间存在显著的回归关系:lg(地上生物量)=3.123+0.84×lg(林龄)-2.019×lg(纬度),(R2=0.431,F2,11=4.161,P=0.045)。秋茄种群生物量随着林龄的增加而增加,随着纬度的升高呈现降低趋势。浙江鳌江河口3年、5年和10年龄人工秋茄林生物量分别为7.13、11.32和24.35 t/hm2,其中5年龄秋茄林生物量仅为广东湛江同龄秋茄林(自然湿地生境)生物量的18%。然而,广东深圳的3年龄秋茄林(人工湿地生境)生物量仅为该研究中同龄秋茄林生物量的9.3%。此外,以≤11年龄的人工秋茄纯林为对象,建立了种群密度与种群植株平均生物量的关系:lg(平均单株地上生物量)=8.468-2.1×lg(种群密度),(R2=0.961,F=99.764,P=0.001),秋茄种群密度越小,平均植株生物量越大,平均单株生物量较符合Yoda提出的-3/2自疏定律为快,自疏指数为-2.1。因此,纬度和林龄是秋茄种群生物量的主要影响因子,生境类型、种群密度等因素对红树林种群或群落生物量的积累也至关重要。     

川西亚高山次生桦木林恢复过程中的生物量、生产力与材积变化

采用空间代替时间的样地调查方法,利用异速生长方程和一元材积表计算不同林龄桦木林的生物量、生产力与材积,结果表明,桦木林乔木层及平均单株地上生物量均随林龄增加而增加,在50 a时达到最大;生产力则先增加而后逐渐减少,乔木层30 a时生产力为7.88 t.hm-.2a-1,到40 a和50 a时,分别下降到5.17 t.hm-.2a-1和1.19.thm-.2a-1;单株平均生产力在30 a时达到最大值1.13 kg.a-1,40 a时下降为0.96 kg.a-1,50 a时略有上升。林分蓄积量随林龄增加而增加,平均生长量在50 a达到最大值3.78 m.3hm-2,连年生长量在30 a时达到最大值6.07 m.3hm-2。平均单株材积增长速度随林龄增加而增加,50 a时平均生长量和连年生长量达到最大值。     

红树林恢复初期莱氏锥滨螺分布动态

树栖腹足类动物是红树林底栖动物的重要组成部分,其组成和分布受到红树植被的影响。因此,在红树林生态修复中,腹足类动物的恢复依赖于植被的发育。滨螺科(Littorinidae)锥滨螺属(Mainwaringia)动物是亚洲红树林的广布种,但针对其在红树林中的分布及种群特征的研究较少,对红树林植被恢复过程中锥滨螺属动物的恢复动态更是鲜有研究。调查了厦门下潭尾湿地秋茄(Kandelia obovata)红树林恢复初期,新记录种莱氏锥滨螺(Mainwaringia leithii)种群恢复的时间动态,并分析其与植被参数的关系。研究发现,红树林恢复初期,秋茄植被生长迅速,株高、冠幅、基径和覆盖度分别由0.5年生幼林的41.3 cm、25.0 cm、1.04 cm和25%增长为8年生样地的179.2 cm、76.7 cm、5.96 cm和95%。在秋茄胚轴种植6个月左右开始记录到莱氏锥滨螺的个体,其密度和生物量在1.5 a后达到最大(分别为136个/m²和1.86 g/m²),而后逐渐降低,种植3 a后秋茄林内莱氏锥滨螺仅零星分布。除8年生的样地,莱氏锥滨...     

西双版纳橡胶林的生物量及其模型

利用30株不同年龄和径阶的橡胶树样木数据,建立了以胸径(D)和胸径的平方乘以树高(D2H)为自变量的生物量回归模型.根据所建立的生物量回归模型,推算了15个1000 m2不同林龄橡胶林的生物量,并分析了其组成和分配特征及不同林龄生物量的变化趋势.林分的总生物量随林龄而增加,7、13、19、25和47年生橡胶林生物量分别为23.98、66.90、150.37、171.12和250.21 t·hm-2.生物量的器官分配以干材所占的比例最大,占50%以上,并随林龄而递增;枝生物量所占比例也随着林龄的增加而增大;叶和根的生物量所占比例则随林龄呈下降趋势.橡胶林生物量远低于本地区的热带季节雨林和石灰山季雨林,但高于本地区的热带次生林及其他热带地区年龄相近的人工林.     

广西不同林龄杉木、马尾松人工林根系生物量及碳储量特征

为了解不同林龄杉木、马尾松人工林地地下根系生物量及碳储量特征,以广西杉木、马尾松主产区5个不同林龄阶段(幼龄林、中龄林、近熟林、成熟林、过熟林)的人工林为研究对象,采用全根挖掘法和土钻法获取标准木根系生物量、灌草根系生物量和林分细根生物量,并测定其碳含量,分析其不同林龄阶段地下根系生物量和碳储量分配特征。结果表明:杉木、马尾松林地下根系总生物量分别在9.06—31.40Mg/hm~2和7.91—53.40Mg/hm~2之间,各林龄阶段根系总生物量总体上呈现随林龄增加而增加的趋势,杉木林细根生物量随林龄的增加呈现出先减后增的趋势,马尾松呈现出逐渐减小的趋势;林分各层次根系碳含量表现为乔木灌木草本、细根;杉木、马尾松地下根系碳储量变化趋势与生物量变化趋势相同,杉木、马尾松林不同林龄阶段各层次根系和土壤细根总碳储量分别在7.56—21.97Mg/hm~2和8.86—29.95Mg/hm~2之间;地下根系碳储量总体上以乔木根系占优势,且随林龄的增大其比例呈增加的趋势。     

深圳福田两种红树林植物叶片分解研究

利用分解袋法研究两种红树林植物(秋茄、桐花)叶片在野外实地分解过程中的干物质和有机C、N、P变化情况.结果表明,秋茄叶片野外分解的速度要比桐花叶片快得多,初始非灰分物质干重(AFDW)损失一半所需的时间秋茄为12d,桐花35d左右.分解开始后,两种叶片的N含量均迅速上升,到达峰值后逐渐下降;而P含量则先略为下降,之后慢慢回升;叶片有机C含量则始终保持在相对较为稳定的水平上.试验的结果还表明,桐花叶片在红树林系统内沿潮汐梯度的不同滩面位置上分解时,各地点的分解速率间无显著差异.     

土壤结构与光照水平对秋茄某些生长和生理参数的影响

在香港的３个红树森样地即黄竹湾（沙土）、西径（沙壤土）和米埔（粘壤土）进行了土壤结构对秋茄（Kandelia candel(L.)Durce)生长和生理影响的研究,并在米埔比较了林内和林外秋茄幼苗的生长和生理参数以观察光照水平的效应。在沙土和沙壤土生长的１．５年秋茄幼苗比粘壤土具有较粗的基径的较高的总生物量,说明秋茄幼苗在沙土和沙壤土中比在粘壤土中生长更好。沙土１．５ 茄幼苗的叶片厚度分别为沙壤土和粘壤土的１．７５和２．０５倍,表明沙土中的秋茄幼苗具有旱生结构以维持体内水分。然而,沙土和沙壤土４．５年秋茄幼树的叶片厚度无显著差异,沙土和沙壤土中１．５年秋茄幼苗分配于根系的生物量比例约为５０％,高于粘壤土的值（约４０％）。沙土和沙壤土中１．５年的秋茄比粘壤土具有较低的叶绿素含量、根系活力、硝酸盐还原酶活性、过氧化物酶（ＰＯＸ）活性、超氧化物歧化酶（ＳＯＤ）活性及较高的丙二醛（ＭＤＡ）含量。米埔１．５年秋茄幼苗在红树林外比林内有更好的长势,具有更大的叶面积、特殊叶面积、叶片数量及生物量。林内幼苗具有较高叶绿素含量,较低叶绿素a/b比值,较高硝酸盐还原酶活性和较强的根系活力,林外幼苗的叶片ＰＯＸ和ＳＯＤ活性比林内的值稍高,ＭＤＡ含量比林内显著要高。     

光照强度对8种红树植物幼苗生长和生物量分配的影响

选取无瓣海桑(Sonneratia apetala Buch-Ham.)、卤蕨(Acrostichum aureum Linn.)、桐花树(Aegiceras corniculatum Blanco.)、老鼠簕(Acanthus ilicifolius Linn.)、木榄(Bruguiera gymnorrhiza Lam.)、秋茄(Kandelia candel Druce.)、银叶树(Heritiera littoralis Ait.)和黄槿(Hibiscus tiliaceus L.)为研究对象,通过遮荫控制实验,研究这8种红树植物幼苗在不同光照强度(自然光强的100%、45%、30%、10%)下的生长和生物量分配特征。结果表明:(1)遮荫对无瓣海桑幼苗相对生长速率、生物量积累、基径的增长和叶片数的增长均有显著的抑制作用;(2)桐花和老鼠簕在遮荫处理下生长状况较好,遮荫对桐花生长的影响不显著,对老鼠簕幼苗的生长则有一定的促进作用;(3)当光照强度降低时,无瓣海桑、秋茄、老鼠簕、桐花树的幼苗都对地上部分投入了更多的生物量,其中秋茄、老鼠簕和桐花树通过提高叶生物量来获取更大的光能捕获能力。研究结果表明,从对光照的生长适应角度来看,桐花、老鼠簕和卤蕨适宜种植在郁闭度较高的林下;秋茄适宜在郁闭度较低的林下种植;真红树无瓣海桑和木榄以及半红树黄槿和银叶树则不适合在林下种植。     

人工生境条件下几种红树植物的净初级生产力比较研究

选择3种红树植物海桑(Sonneratia caseolaris)、秋茄(Kandelia candel)和桐花树(Aegiceras corniculatum),每种分别按45%、30%和15%的面积比例种植于滩涂海水养殖塘.种植后连续2年对红树植物进行生态监测.结果表明,海桑增高457.0cm,基径增加86.1mm,成活率92.9%;桐花树高、基径分别增长2.1cm和36.5mm,成活率93.9%;秋茄成活率44.7%,增高20.4cm、基径增加2.4mm,说明在不受自然潮汐影响的人工生境条件下,海桑和桐花树对环境的适应能力强,生长较好,秋茄的生长适应性较差.据不同时期树高、基径与干、枝、叶、根的生物量,求得植物各器官生物量与树高、基径的回归方程,分析了3种红树植物的生物量与净初级生产力.海桑单位面积生物量5597.8g·m^-2,桐花树962.5g·m^-2,秋茄66.0g·m^-2.生物量在植物各器官的分配按大小排序,海桑为树干＞树枝＞树根＞树叶;桐花树为树叶＞树枝＞树干＞树根;秋茄为树干＞树根＞树叶＞树枝.单位面积净初级生产力海桑为7051.5g·m^-2,桐花树1105.8g·m^-2,秋茄93.0g·m^-2.高生产力伴随高归还量,凋落物归还量占净初级生产力的比重为海桑20.5%、桐花树15.4%、秋茄7.%.     

Mapping and characterization of mangrove plant communities in Hong Kong

Ecological surveys were carried out to investigate the distribution and characterization of remaining mangrove stands in Hong Kong. The field studies indicate that 43 mangrove stands, excluding Mai Po Nature Reserve, still remained along the coastline of Hong Kong despite tremendous reclamation and development which occurred in the past 40 years. Most mangrove stands were found in Deep Bay (western part)and Sai Kung District (eastern coasts). The total areas occupied by these mangrove stands were 178 ha,varying from a very small stand (with 1–2 mangrove shrubs) to fairly extensive mangroves in Deep Bay (> 10 ha). It appeared that mangrove stands located in Deep Bay area were larger than those in the eastern coasts. Twenty plant species were identified from these stands, with 13 being exclusive or associate mangrove species. The major constituent species were Kandelia candel, Aegiceras corniculatum, Excoecaria agallocha and Avicennia marina. Rare species such as Heritiera littoralis were only found in a few mangrove stands. Out of the 43remaining mangrove stands, 23 were more worthwhile for conservation and their plant community structures were further investigated by transect and quadrat analyses. The importance values (sum of relative abundance,frequency and dominance) show that K. candel was the most dominant species. Species richness and Simpson's indices together with tree height, tree density and canopy area fluctuated significantly between mangrove stands. These values were used to prioritize the conservation potential of the remaining mangrove stands in Hong Kong. This revised version was published online in August 2006 with corrections to the Cover Date.     

无瓣海桑、海桑、秋茄红树人工林群落动态及物种多样性研究

对红树植物无瓣海桑、海桑、秋茄3种人工林群落动态及物种多样性特征的系统研究结果表明,无瓣海桑群落和海桑群落的乔木层明显分为上层和中层两个亚层,上层木为无瓣海桑或海桑,中层木主要为秋茄和桐花树;秋茄群落的乔木层为单一层次,基本由秋茄组成．在无瓣海桑群落和海桑群落中,优势种群无瓣海桑或海桑仅有高龄级个体存在,未出现自然更新现象;秋茄和桐花树为旺盛增长种群,有可能成为优势种群,表明无瓣海桑和海桑为先锋造林树种,在裸滩种植可以促进其它红树植物的天然定居生长;在秋茄群落中,秋茄为旺盛增长种群,能够自然：更新演替,桐花树和海莲属初生增长种群．无瓣海桑群落和海桑群落的物种组成和物种多样性指标较接近,基本包含秋茄群落中的主要物种秋茄、桐花和海莲。表明无瓣海桑和海桑能与这些物种协调共生,同时种植无瓣海桑或海桑可以形成多样化的红树林群落;无瓣海桑群落和海桑群落在形成初期,种植密度较大时,物种多样性较高;密度相近时。形成初期随林龄的增加。其物种多样性略有提高．     

The growth of Kandelia candel seedlings in mangrove habitats of the Zhangjiang estuary in Fujian, China

Propagules of Kandelia candel collected from the Zhangjiang estuary were planted in mangrove habitats along the intertidal gradient. The rooting rates of K. candel propagules varied spatially. The lowest rate occurred in Avicennia marina forest (69.7%). The rates were higher in K. candel forest (90.0%), at the fringe of the mangrove forest (89.3%) and on the bare tidal flat outside the mangrove forest (82.7%). After one year, the survival rates of seedlings planted under A. marina forest, K. candel forest, at the fringe of the mangrove forest, and on the bare tidal flat were 13.7%, 54.7%, 76.0%, and 34.7%, respectively. Among the surviving K. candel seedlings, those at the fringe of the mangrove forest and on the bare tidal flat had greater height, stem diameter, leaf number, leaf area, and biomass than those under A. marina and K. candel forests. These results demonstrated that establishment and growth of K. candel seedlings occurred successfully at the fringe of the mangrove forest, but were the worst under A. marina forest. The performance of K. candel seedlings was independent of physico-chemical characters of sediment. However, interspecies competition, propagule predation by insects and crabs, and the incident light had significant effects on seedling survival and growth.     

Variation in Carbon Storage and Its Distribution by Stand Age and Forest Type in Boreal and Temperate Forests in Northeastern China

The northeastern forest region of China is an important component of total temperate and boreal forests in the northern hemisphere. But how carbon (C) pool size and distribution varies among tree, understory, forest floor and soil components, and across stand ages remains unclear. To address this knowledge gap, we selected three major temperate and two major boreal forest types in northeastern (NE) China. Within both forest zones, we focused on four stand age classes (young, mid-aged, mature and over-mature). Results showed that total C storage was greater in temperate than in boreal forests, and greater in older than in younger stands. Tree biomass C was the main C component, and its contribution to the total forest C storage increased with increasing stand age. It ranged from 27.7% in young to 62.8% in over-mature stands in boreal forests and from 26.5% in young to 72.8% in over-mature stands in temperate forests. Results from both forest zones thus confirm the large biomass C storage capacity of old-growth forests. Tree biomass C was influenced by forest zone, stand age, and forest type. Soil C contribution to total forest C storage ranged from 62.5% in young to 30.1% in over-mature stands in boreal and from 70.1% in young to 26.0% in over-mature in temperate forests. Thus soil C storage is a major C pool in forests of NE China. On the other hand, understory and forest floor C jointly contained less than 13% and <5%, in boreal and temperate forests respectively, and thus play a minor role in total forest C storage in NE China.     

福建漳江口红树林区秋茄幼苗生长动态

通过福建漳江口红树林自然保护区内8个样方24个小样方人工种植600个秋茄胚轴,在3a时间内对秋茄胚轴建立、幼苗生长以及环境因子进行定期观测。研究结果表明：林缘空地的秋茄生长状况良好,白骨壤林内最不利于秋茄幼苗的生长。潮位、盐度、底质土壤理化因子不是造成该样地各样方间秋茄幼苗生长差异的主要原因。动物取食、光照状况以及种间竞争是限制秋茄生长的主要环境因子。秋茄胚轴在长根前易于随潮水漂走,底质土壤中自骨壤致密的根系抑制了秋茄胚轴的定植,导致白骨壤林内秋茄幼苗漂走的数量最多。昆虫和螃蟹等动物的取食是导致林内已经固着生长的秋茄幼苗大量死亡的最主要原因,而林外被取食的幼苗个体极少。此后秋茄幼苗能否继续成长,主要取决于幼苗所接受到的光照条件。3a后,在荫蔽的树冠下,秋茄幼苗无法存活;而在林外,秋茄幼苗已经长成幼树。在林外滩涂上迅速生长的互花米草,也将影响秋茄幼苗的更新和生长。     

Carbon Accumulation Patterns During Post-Fire Succession in Cajander Larch (Larix cajanderi) Forests of Siberia

Increased fire activity within boreal forests could affect global terrestrial carbon (C) stocks by decreasing stand age or altering tree recruitment, leading to patterns of forest regrowth that differ from those of pre-fire stands. To improve our understanding of post-fire C accumulation patterns within boreal forests, we evaluated above- and belowground C pools within 17 Cajander larch (Larix cajanderi) stands of northeastern Siberia that varied in both years since fire and stand density. Early-successional stands (<20-year old) exhibited low larch recruitment, and consequently, low density, aboveground larch biomass, and aboveground net primary productivity (ANPP_tree). Mid-successional stands (21- to 70-year old) were even-aged with considerable variability in stand density. High-density mid-successional stands had 21 times faster rates of ANPP_tree than low-density stands (252 vs. 12?g?C?m^?2?y^?1) and 26 times more C in aboveground larch biomass (2,186 vs. 85?g?C?m^?2). Density had little effect on total soil C pools. During late-succession (>70-year old), aboveground larch biomass, ANPP_tree, and soil organic layer C pools increased with stand age. These stands were low density and multi-aged, containing both mature trees and new recruits. The rapid accumulation of aboveground larch biomass in high-density, mid-successional stands allowed them to obtain C stocks similar to those in much older low-density stands (~8,000?g?C?m^?2). If fire frequency increases without altering stand density, landscape-level C storage could decline, but if larch density also increases, large aboveground C pools within high-density stands could compensate for a shorter successional cycle.     

潮滩红树植物抗低温适应的生态学研究

采用电导法定量测定了中国东南沿海红树植物叶片的抗寒力变化。结果表明;(1)海南琼山东寨港主要红树种类冬季抗寒力(半致死温度)介于-2.3～-6.8℃之间,其中红树科植物抗寒力较强,多数种类属于低温敏感性相对较弱的L类型;海桑科和楝科红树种类抗寒力较弱,属于低温敏感性较强的H类型。(2)随纬度升高(个别地点除外),秋茄(Kandelia candel)、桐花树(Aegiceras corniculatum)和红海榄(Rhizophors,stylosa)抗寒力增强,呈现种群分化趋势。(3)同一地点,秋茄和桐花树抗寒力有明显季节变化：夏季最低,秋冬两季高于春季。(4)同一群落内,生长于中潮区滩面的秋茄抗寒力强于高潮区,但桐花树抗寒力在各个滩面相差木大。(5)秋茄和桐花树树冠上不同部位叶片的抗寒力不同,由表及里,由上至下,呈降低趋势。红树叶片抗寒力的种群分化、季节变化和部位差异是其趋异适应的结果,有益于红树植物的生存和繁育。