广东番禺红树林造林研究

结合广东番禺红树林造林的现状,对影响红树林幼苗成活率和生长状况的因素进行初步分析,并据此提出提高造林保存率的措施等。影响红树林造林成活及生长的因素为①水深潮水越深,红树幼苗成活率越低,生长越差;②风浪海面风浪越大,红树幼苗受干扰越大,成活和生长越差;③人为活动干扰会严重影响红树幼苗的成活和生长;④造林地的杂草会影响某些红树植物幼苗的光照条件;⑤海滩垃圾废物会挂断和压倒大量红树幼苗;⑥海滩石油污染会阻止红树胚轴的萌发;⑦幼苗种植时越粗壮,种植得越精细,则种植后生长越好。并提出提高造林成效的措施①加强维护和管理包括护理受损伤的红树幼苗,清除塑料袋等垃圾物,制止在红树幼苗区的捕捞活动,造林前清除杂草和固定某些红树植物幼苗;②补植受破坏的红树幼苗和扩大种植。     

广东番禺红树林造林研究

结合广东番禺红树林造林的现状,对影响红树林幼苗成活率和生长状况的因素进行初步分析,并据此提出提高造林保存率的措施等。影响红树林造林成活及生长的因素为：①水深：潮水越深,红树幼苗成活率越低,生长越差;②风浪：海面风浪越大,红树幼苗受干扰越大,成活和生长越差;③人为活动干扰会严重影响红树幼苗的成活和生长;④造林地的杂草会影响某些红树植物幼苗的光照条件;⑤海滩垃圾废物会挂断和压倒大量红树幼苗;⑥海滩石油污染会阻止红树胚轴的萌发;⑦幼苗种植时越粗壮,种植得越精细,则种植后生长越好。并提出提高造林成效的措施：①加强维护和管理：包括护理受损伤的红树幼苗,清除塑料袋等垃圾物,制止在红树幼苗区的捕捞活动,造林前清除杂草和固定某些红树植物幼苗;②补植受破坏的红树幼苗和扩大种植。     

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。     

红树林保护区的生态环境效益

红树林保护区是一个由生物和环境组成的有机组合的开放系统, 是世界上最富多样性,生产力最高的海洋生态系统之一。红树林特殊的植物生态特性胎生 红树植物不少具有胎生现象, 这种特征有利于在海滩上繁殖和远距离传播。一般情况是红树植物的果实成熟时仍留在树上, 种子在母树上的果实内发芽, 形成幼苗, 掉进泥中后, 即可扎根成苗; 若掉入涨潮水中, 可远漂传播, 遇到潮落时再在滩泥中扎根生长。根系 红树植物具特殊的根系, 可分为支柱根、板状根和呼吸根。即适应泥泞的红树植物, 从茎基伸出拱形下弯的支柱根或宽厚的板根, 以抗御风浪和起到…     

红树林生物多样性恢复

从红树植物及与之密切相关的底栖动物的多样性恢复出发,分析了我国当前红树林恢复存在的主要问题,并提出了对此需要着重进行的基础研究思路。在红树植物多样性恢复方面,胎生种类的繁殖体在母树上就已萌发,成熟繁殖体可直接用于海滩造林,大多数种类已用于红树林恢复;而非胎生红树植物繁殖体的萌发脱离母树,成熟繁殖体难以直接在海滩造林,其育苗具有一定难度,因此较少用于红树林恢复,可以通过非胎生红树植物的种子休眠、生理生态和化感作用等方面的研究,极大限度地增加红树植物生态恢复的种类。在动物多样性恢复方面,底栖动物生物多样性恢复还是“非定向”的,可通过在具类似底质、盐度和潮位的河口海岸地段不同恢复时间的人工红树林,研究红树林植被不同恢复措施（主要是种植密度和种类选择）对底栖动物生物多样性的影响,使得红树林的生态恢复在改造生态系统其它生物组份上不会呈现盲目性和不可预测性。     

外来红树植物无瓣海桑引种及其生态影响

无瓣海桑是我国首个从国外引进并大面积推广种植的红树植物,生长快,适应性强,已成为华南沿海红树林恢复造林的主要树种。但近年来无瓣海桑引种已引起较大争论,焦点是无瓣海桑是否会对乡土红树植物生长产生不利影响,是否会造成生态入侵,是否应限制推广种植。根据引种以来的研究成果,对无瓣海桑的生态适应性、种植技术、生产力与物质循环、生态影响等四个方面的引种研究进行综述;分析无瓣海桑引种对乡土红树植物生长的影响和生态入侵可能性,对无瓣海桑引种造林提出建议。指出今后无瓣海桑引种的的研究重点为:无瓣海桑引种的生态监测与入侵评估;对滩涂水生生物的影响;与乡土红树植物优化配置的混交种植技术;无瓣海桑的资源化利用。     

人工红树林的生长与病虫害防治的研究

为了配合“十五”863项目研究红树林修复海水滩涂养殖水的营养污染,在深圳海上田园旅游区的科技试验区鱼塘构筑种植岛种植一年生红树植物海桑(Sonneratia caseolarisL.)、桐花树(Ageiceras corniculatum(L.)Blanco)、秋茄(Kandelia candelL.Druce)并监测了解其生长发育的情况及物候期;掌握危害红树林植物生长的主要病虫害.结果表明,海桑生长速度快,各生长形态指标都远大于秋茄和桐花树,并且具有良好的抗逆特性但怕冷冻.秋茄生长速度慢,对环境的适应能力差,怕水淹,成活率最低;桐花树抗逆性强,成活率最高.红树林植物幼龄时期容易受到病虫害严重威胁,要做好防治工作,保证红树林植物的健康生长.     

红树林的生态学

组成红树林(Mangrove)的植物并非全是红树科(Rhizophoraceae)的植物,因此我们把组成红树林的植物称为红树植物(Mangrove-Plants),以与红树科植物相区别,因为红树科植物井非都能在周期性潮汐浸渍的海滩或河流中形成群落,例如红树科中鹅山木(Carallia)和山红树(Pellacalyx)二属植物是在陆地上或山林中生长的,不具有红树植物的生态习性,它们不是红树植物。这说明植物的系统发育和它们的生态习性是两回事,不一致的。     

Competition and abiotic stress affect the size of mangroves near their geographic range limit

竞争和非生物胁迫影响处于地理分布边界的红树植物的个体大小 关于红树植物竞争的研究大多局限于幼苗和人工林。我们首次对天然红树林中成年红树的种内竞争进行了控制实验研究,旨在检验竞争和非生物因子在决定红树植物个体大小中的相对重要性。研究样 地位于靠近红树林地理分布边界的美国德克萨斯州阿兰萨斯港(Port Aransas)附近区域。该区域的红树林由“灌丛”状的黑红树(萌芽白骨壤,Avicennia germinans)单一物种组成。我们对10个样方中原生红树 林进行疏伐,形成系列红树林覆盖度梯度,在2013–2019年期间观测各样方中红树植物的生长指标,量化分析红树林覆盖度对红树植物生长的影响;并于2019年调查了红树林的冠层高度。研究结果表明,在该研究期间,红树植物的相对生长速率随着红树林覆盖度的增加而降低,100%红树林覆盖度样方中的红 树植物大小几乎没有增长,说明它们已经达到了该红树林密度条件下的最大尺寸。在红树林覆盖度降低 的样方中,株高明显增加,在红树林覆盖度为11%的样方中,红树植物株高增加了约52%。对比临水岸 边和林内两种生境中的样方,处于临水岸边生境的红树林冠层高度比处于林内生境的高约30%,且这两 种生境的红树林冠层高度均随红树林覆盖度的增加而降低。叶片叶绿素含量和冠层光截留量的测定数据 显示,该区域红树植物的生长也受到氮限制的影响。由此表明,处于地理分布边界的“灌丛”状红树林一 方面受到营养的限制,另一方面红树植物种内个体间仍存在较为强烈的竞争,且种内竞争对红树植物生长的影响较该红树林内非生物生境因子更为重要。     

红树植物淹水胁迫响应研究进展

潮汐淹水是红树植物面临的主要环境胁迫之一,也是导致目前红树林造林成活率低的一个关键因子。由于长期适应于水淹生境,红树植物发育出一套适应于潮间带生长的抗淹水机制。综述了与红树植物相关的抗淹水胁迫响应机制,包括了形态结构、生长、水分和光合作用、膜脂过氧化系统和根系脱氢酶系统、内源激素和胁迫多胺等5个方面。提出应用人工潮汐系统研究红树植物的淹水抗性机理是确定不同种类红树植物的耐淹水能力的有效手段。并指出生长的研究是淹水胁迫响应研究的基础,而与分子手段相结合的激素水平的研究将在红树植物抗性胁迫研究中得到重视。     

人工红树林幼林藤壶危害及防治研究进展

随着近年来红树林恢复性造林面积的扩大,海洋污损生物藤壶对红树林幼林的危害问题日益突出.文中综述了藤壶附着的生物化学、藤壶在红树林附着的生态学、藤壶对人工红树林幼林的危害和国内所采用的化学药物防治措施等方面的研究进展,以及今后的研究方向.藤壶在红树林的附着和分布模式受海水盐度、浸淹深度、林分郁闭度、水文条件等环境因素和生物因素的影响.而藤壶胶粘蛋白的氨基酸组成、一维结构,胶粘蛋白在水下的交联、组装和胶粘的过程与机制,以及藤壶危害红树幼苗的机制和危害权重尚需要深入探讨.研究红树植物对藤壶附着的响应和长期适应机制将为藤壶的防治提供更多的启示.     

The abundance and growth of Avicennia marina and Rhizophora stylosa in the low shore zone of Darwin Harbour,Northern Territory

Abstract The growth and distribution of the two mangrove seedling species, Avicennia marina (Forsk.) Vierh. and Rhizophora stylosa Griff., were studied in the low-shore zone at three locations along two estuaries of Darwin Harbour to determine how growth varied along the estuary and within the habitats of the low shore zone. The low shore environment was heterogenous for factors such as salinity and light, with substantial variation within and between locations. Seedlings of Avicennia were in higher densities in light gaps than in the adjacent forest, and density in both habitats decreased towards the mouth of the estuary. Growth of Avicennia seedlings, as measured through in situ growth trials and plant harvests, increased towards the mouth of the estuary. Results for Rhizophora seedlings were more complex although some similar trends were evident. This may have been due to the greater early survival of Rhizophora seedlings compared to Avicennia seedlings. The importance of propagule origin was investigated, for Rhizophora, by transplanting propagules between locations along one estuary. Increased seedling survival was observed at the propagule source site; however, this effect was subtle and probably not the most important factor affecting seedling survival at a site.     

Ecology of Mangrove Growth and Recovery in the Lesser Antilles: State of Knowledge and Basis for Restoration Projects

Whereas the increasing knowledge on tropical coastal wetlands highlights the ecological and economical importance of such ecosystems, anthropogenic activities within the coastal zone have caused substantial, irreversible losses of mangrove areas in the Lesser Antilles during the last decades. Such a paradox gives strength to compensatory policy efforts toward mangrove restoration. We review the available knowledge on the ecology of mangrove growth and recovery in the Lesser Antilles as a contribution to possible restoration projects in such islands. Distribution of species follows a general pattern of seaward/landward zonation according to their respective tolerance to flooding and to pore‐water salinity. An experimental study of seedling growth following simulated oil spill has documented the tolerance of Rhizophora mangle and Avicennia germinans seedlings to oil concentration in soils and the effects of natural biotic and abiotic factors on seedlings growth and survival. Monitoring mangrove recovery following hurricane Hugo has given information on growth patterns, from seedling to sapling stages, according to species and site conditions. Forest recovery was mostly due to pre‐established seedlings. For the large Rhizophora propagules, buoyancy appears to be a quite inefficient way of dispersal far inland from the sea shore or riversides. Causes of recovery failure are discussed. From these results we attempt to answer the questions when, where, how to plant mangroves, and what species to use.     

辽东山区长白落叶松人工林天然更新障碍分析

通过对辽东山区不同间伐强度下长白落叶松林内种子库,种子萌发,幼苗出现、成活与生长的观测,分析了长白落叶松天然更新的主要影响因素.结果表明:40年生落叶松人工林的种子雨中,有30%的种子有活力,可以满足天然更新的需要;土壤种子库的种子主要分布在枯枝落叶层,4月下旬林内种子开始萌发,6月幼苗数量达到最大,幼苗累计出现率与间伐强度(光照)之间无显著相关,只受到地被物的影响;随间伐强度的增加,幼苗平均存活率提高,但林下幼苗生长缓慢,苗高均不超过6 cm;林内当年幼苗9月全部消失,没有超过1年生的幼苗,但皆伐迹地的更新幼苗存活较多、生长良好.初步确定地被物和光照是辽东山区长白落叶松天然更新的主要障碍因子.     

Away‐field advantage: mangrove seedlings grow best in litter from other mangrove species

Plant community composition can impact ecosystem processes via litter feedbacks. Species variation in litter quality may generate different patterns of nutrient supply for plants that are dependent on litter inputs. However, it is not known whether plants grow faster in their own litter, litter from other species, or in litter mixtures from multiple species. To test whether litter identity and mixture status influenced mangrove seedling growth, biomass allocation, and stoichiometry, we performed mesocosm experiments. Two species of mangrove seedlings, Avicennia germinans, black mangrove and Rhizophora mangle, red mangrove, were exposed to all possible combinations of three mangrove litter types and were isolated from all other nutrient inputs. Litter treatments significantly altered seedling growth. Seedlings from both mangrove species grew most rapidly in litter from a different species rather than their own, irrespective of litter chemical quality, decomposition rate, and nitrogen release. Litter mixtures from white and black mangroves caused black mangroves to grow 65% more than expected. Litter treatments did not impact seedling root:shoot ratios or tissue C:N. Our finding that seedlings grow best in litter from other species may indicate a mechanism that helps sustain the coexistence of dominant species.     

Simulated sea level change alters anatomy, physiology, growth, and reproduction of red mangrove (Rhizophora mangle L.)

Tropical coastal forests – mangroves – will be one of the first ecosystems to be affected by altered sea levels accompanying global climate change. Responses of mangrove forests to changing sea levels depend on reactions of individual plants, yet such responses have not been addressed experimentally. We report data from a long-term greenhouse study that assessed physiological and individual growth responses of the dominant neotropical mangrove, Rhizophora mangle, to levels of inundation expected to occur in the Caribbean within 50–100 years. In this study, we grew potted plants in tanks with simulated semidiurnal (twice daily) high tides that approximated current conditions (MW plants), a 16-cm increase in sea level (LW plants), and a 16-cm decrease in sea level (HW plants). The experiment lasted 2½ years, beginning with mangrove seedlings and terminating after plants began to reproduce. Environmental (air temperature, relative humidity, photosynthetically active radiation) and edaphic conditions (pH, redox, soil sulfide) approximated field conditions in Belize, the source locale for the seedlings. HW plants were shorter and narrower, and produced fewer branches and leaves, responses correlated with the development of acid-sulfide soils in their pots. LW plants initially grew more rapidly than MW plants. However, the growth of LW plants slowed dramatically once they reached the sapling stage, and by the end of the experiment, MW plants were 10–20% larger in all measured growth parameters. Plants did not exhibit differences in allometric growth as a function of inundation. Anatomical characteristics of leaves did not differ among treatments. Both foliar C:N and root porosity decreased from LW through MW to HW. Relative to LW and HW plants, MW plants had 1–7% fewer stomata/mm², 6–21% greater maximum photosynthetic rates, 3–23% greater absolute relative growth rates (RGRs), and a 30% higher RGR for a given increase in net assimilation rate. Reduced growth of R. mangle under realistic conditions approximating future inundation depths likely will temper projected increased growth of this species under concomitant increases in the atmospheric concentration of CO₂.     

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。     

Population dynamics of a Sonneratia caseolaris stand in the Lam River estuary of Vietnam: a restoration perspective

Species composition, age distribution, and their relationship with land height from the datum line (LH) of the Sonneratia caseolaris stand, which grows in the Lam River estuary in Vietnam, were surveyed to obtain fundamental knowledge that aimed at contributing to mangrove restoration. The data gathered on the sandbar consists of three mangrove species and one mangrove associate species, with one non-mangrove species, and were divided into three communities. In terms of the age distribution of the S. caseolaris–Aegiceras corniculatum community, the tree-phase densities for both species are lower than those exhibited by younger phases. In its succession, the seedlings of S. caseolaris and A. corniculatum are primarily recruited at the mean tide level (MWL) in the early stages. Then, A. corniculatum expands to the lower tide zone primarily on mud flat bare land. For both species, full irradiance on the bare land in the low tide zone below MWL is crucial for growth, but S. caseolaris, which propagates by releasing small seeds, can barely survive in the low tide zone because its seeds are easily flushed away. In contrast, A. corniculatum, which propagates using crypto-viviparous seedlings, has a higher survival rate in the low tide zone. As a result, the LH of seedlings of A. corniculatum distribution is significantly lower than that of the distribution of S. caseolaris trees (p?<?0.05). It is important to provide appropriate environmental conditions for forest restoration in order to promote succession. The findings from the current study on population dynamics related to LH and tidal conditions are expected to be applied to platforms for S. caseolaris stands and mangrove restoration.