山东省长岛县南长山岛黑松和刺槐人工林的碳储量

利用乡土树种改造大面积人工纯林已成为我国海岛人工林近自然化经营的有效模式.采用生物量相对生长方程和样地调查数据相结合的方法,对山东省长岛县南长山岛人工林的优势树种黑松和刺槐的碳储量进行估算.结果表明:黑松和刺槐人工林乔木层平均碳储量分别为56.81和37.26 t·hm^-2,均高于山东省乔木林的平均碳储量(27.62 t·hm^-2).坡向是影响海岛乔木碳储量的重要环境因子,林分密度是影响海岛乔木层碳储量的重要生物因子.黑松人工林乔木层生物量平均累积速率与树龄没有明显的相关性.具有良好固碳功能的黑松是南长山岛的理想树种.     

深圳福田无瓣海桑与海桑人工林鸟类群落研究及生态评价

报道深圳福田无瓣海桑＋海桑人工林和天然林树林鸟类群落的组成特征、密度、相似性、生物多样性等方面的调查研究结果。并通过比较的方法,从鸟类群落学的角度,对无瓣海桑＋海桑人工林的生态功能进行了初步分析和评价。认为：从目前情况看,无瓣海桑和海桑作为深圳沿海人工造林的主要引进树种,对原有红树林生态系统的结构和功能暂时没有不利影响,对尽快恢复和发展红树林地的面积,提高原有红树林生态系统的生物多样性具有积极的作用。建议：①必须采取有效措施防止生态的入侵;②在大面积种植无瓣海桑＋海桑人工林时间种适当面积的当地红树树种。     

不同立地条件对济南千佛山侧柏林生长影响的初步研究

侧柏(Platycladus orientalis Franco,英文名为Oriental arborvitae)为喜暖旱中生乔木。侧柏林在群落分类上属于温性针叶林植被型、侧柏林群系组、侧柏林群系。侧柏是我国主要造林树种之一,广泛分布于全国各地,作为中心分布区之一的山东省。     

子午岭人工林土壤微生物生物量及酶活性

数十年来,黄土高原的生态恢复取得了显著的效益,不仅遏制了当地的土壤流失,改善了土壤质量,同时也减少了向黄河的输沙量.但是,区域森林物种和群落演替还远未得到充分发展.子午岭林区及其高度发达的森林群落,作为先进的生态区,可以将实践经验和知识借鉴到中国黄土高原的其他地区,有助于确定最有效的人工林树种,以便今后更好地进行生态恢复.为了系统地了解典型的当地树种对土壤性质的潜在影响,本研究以黄土高原子午岭天然次生林区生长状况较好的人工林(刺槐、油松和侧柏)为研究对象,并以子午岭林区顶极群落辽东栎天然林为对照,这4种林型具有较一致的树龄(25年)、立地条件等.采用传统方法测定4种乔木林0～20 cm土壤理化性质、土壤酶活性(蔗糖酶、脲酶和碱性磷酸酶)和土壤微生物生物量碳、氮.结果表明: 1)土壤蔗糖酶活性为16.94～64.49 mg·g^-1·24 h^-1,脲酶活性为0.15～0.26 mg·g^-1·24 h^-1,碱性磷酸酶为0.65～1.23 mg·g^-1·24 h^-1,且侧柏土壤的3种酶活性均显著高于刺槐和油松土壤.从3种酶活性几何平均值来看,侧柏土壤酶活性甚至高于辽东栎;2)土壤微生物生物量碳、氮变化范围分别为247.37～529.84 mg·kg^-1、41.48～77.91 mg·kg^-1,均为侧柏>油松>刺槐,且侧柏显著高于油松和刺槐.辽东栎土壤微生物生物量碳高于侧柏,而微生物生物量氮低于侧柏,但差异均不显著;3)油松土壤溶解性碳、氮含量较高,甚至高于土壤微生物生物量碳、氮,说明油松土壤中溶解性有机物是较微生物生物量更主要的活性养分;4)土壤微生物生物量碳、氮与土壤有机碳和全氮含量呈显著正相关性,刺槐和油松土壤蔗糖酶、脲酶和碱性磷酸酶活性分别与土壤有机碳、全氮和全磷含量呈显著正相关;5)主成分分析结果表明,植被类型对土壤微生物生物量碳和氮、有机碳、全氮、碳磷比、氮磷比、脲酶影响较大,土壤微生物生物量碳、氮、碳磷比、氮磷比和氮与磷呈负相关,土壤溶解性碳、氮与碳氮比呈负相关.表明侧柏是较油松和刺槐更适用于南部森林带的造林树种.     

外来植物火炬树水浸液对土壤微生态系统的化感作用

引种自北美的外来植物火炬树(Rhus typhina L.)是中国北方主要造林树种之一.然而,近年来分布区的不断扩大暗示着该树种的潜在入侵性.以火炬树为对象,研究火炬树不同浓度(0、0.005、0.025、0.1g/mL)的鲜枝叶水浸液对土壤微生物群落结构、酶活性、土壤养分含量及土壤矿化的影响.研究结果表明:随着水浸液浓度的提高,火炬树增加了细菌和真菌的数量;火炬树对所测土壤酶活性产生了不同程度的影响,脲酶和磷酸酶均有随着水浸液浓度的提高而增大的趋势,而蔗糖酶活性受影响不明显;随水浸液浓度升高,火炬树显著提高了土壤全碳、全钾、速效氮、有效磷、速效钾的含量,对土壤含水量、pH值、全氮与全磷没有显著影响;同时,火炬树通过促进微生物的矿化速率,提高了土壤无机氮的供给.以上结果表明,火炬树可以改变土壤的微生物组成和土壤酶活性并影响土壤相关营养元素循环,从而为自身的入侵创造有利条件.本研究揭示外来植物火炬树水浸液对土壤微生态系统的影响,从化感间接作用角度为火炬树的潜在入侵性提供进一步的数据支持.     

侧柏林高生长和径向生长及其与经营措施的关系（简报）

侧柏(Platycladus orientalis)原产中国,具有较大的环境价值和经济价值,是我国主要造林树种之一。山东省位于我国暖温带南部,是侧柏林的中心分布区之一。境内现有侧柏人工林149万亩,为褐土上分布面积最大的森林类型。     

豫西黄土丘陵区不同林龄栎类和侧柏人工林碳、氮储量

利用空间代替时间样地调查法,分析了豫西黄土丘陵区栎类和侧柏人工林生态系统碳、氮储量的分布格局,以及不同土层碳储量和氮储量随林龄的动态变化.结果表明:随着树龄的增加,两类人工林乔木层和枯落物层碳储量均增加,土壤碳储量和氮储量主要在表层(0~20 cm)汇聚,且各土层碳储量和氮储量随着林龄增加表现为减少-增加-减少的趋势.各林龄栎类人工林土壤表层碳、氮储量分别为20.31~50.07和1.68~2.12 t·hm^-2;不同林龄侧柏人工林土壤表层碳、氮储量分别为23.99~48.76和1.59~2.34 t·hm^-2;各林龄栎类和侧柏人工林生态系统的碳储量分别为52.04~275.82和62.18~279.81 t·hm^-2;侧柏人工林碳汇能力略高于栎类人工林.土壤C/N随着造林年限的增加呈增加趋势.     

大造桥虫对火炬树的危害及其发生特点

火炬树ＲｈｕｓｔｇｈｉｎａＬｉｎｎ．原产北美,以其适宜地域广、成林速度快、净化空气作用强、秋后红叶观赏价值高,而成为我地区荒山荒滩主要绿化树种和城乡主要美化树种。１９９４年９月发现,大造桥虫在我区１００ｈｍ２、５年生火炬树上大发生。虫株率１００％,平均虫口密度０．６头／复叶,单叶几乎全被食光,使火炬树失去净化、绿化、美化作用。大造桥虫ＡｓｃｏｔｉｓＳｅｌｅｎａｒｉａ（Ｄｅｎｉｓｅｔ　Ｓｃｈｉｆｆｅｒｍｕｌｌｅｒ）属鳞翅目尺蛾科,国内南方省份多有该虫的分布,而在北方火炬树上大发生成为火炬树的主要害…     

青藏高原东缘不同树种人工林对土壤酶活性及养分的影响

为评价不同树种人工林对土壤酶及养分的影响,选择立地条件和营林方式相同的4种人工林(连香树[CJ]、油松[PT]、落叶松[LK]和华山松[PA])为研究对象,以落叶灌丛(QC)为对照,比较不同树种人工林地土壤酶活性和土壤养分的变化。结果显示:(1)造林降低了土壤酸性磷酸酶、脱氢酶、β-葡萄糖苷酶和过氧化氢酶活性,但人工造林后土壤脲酶活性增加;(2)造林也明显影响了土壤养分,与对照林地相比,除CJ人工林土壤中磷(P)略高外,造林地土壤有机碳(TOC)、氮(N)、水可提取有机碳(WEOC)和氮(WEON)、铵态氮(NH+4-N)和硝态氮(NO-3-N)均降低;(3)不同的人工林树种之间土壤养分及酶活性也存在一定的差异性,CJ和LK人工林土壤C、N、P及相关酶活性明显不同于PT和PA人工林;(4)土壤酶与养分变化有一定的相关性,除转化酶和多酚氧化酶反应较迟钝外,其它酶对环境反应较敏感。综合分析表明,在川西地区选择高密度单一树种造林并没有改善土壤养分和酶活性,在该地区选择落叶或阔叶树种造林可使土壤肥力恢复。     

浅谈油松新育苗的培育及注意事项

油松是西北地区荒山造林的先锋树种。油松苗的培育可分两种:容器或播种。无论容器,还是播种,油松新育苗的培育都要遵循一定顺序,从采种、选地、整地到处理种子和播种都要科学培育。播种后,还要科学管理,注意防寒、防冻,以确保油松新育苗的安全、优质。     

Invasion possibility and potential effects of Rhus typhina on Beijing municipality

Rhus typhina, an alien species introduced from North America, was identified as a main afforestation species in Beijing municipality. However, its invasiveness is still at odds. To clariflj this problem, we applied the North American Screening System and the Australian Screening System to preliminarily predict its invasion possibility. Both screening systems gave the same recommendation to "reject". The geographical distribution was surveyed, with the population features of R.typhina against the native plant communities being assessed. With anthropogenic assistance, R. typhina has been scattered on almost all habitats from downtown to mountains, including roadsides, farmlands and protected areas. As a clonal shrub,R. typhina possessed a high spreading rate, varying from 6.3 m13 years at sterile habitats to 6.7m/3 years at fertile ones.Significantly lower species richness, individual density and diversity were observed in the R. typhina community than those of the native Vitex negundo Linn.var. heterophylla (Franch.) Rehd. community at both sterile and fertile habitats. Continual wide plantation of R. typhina may further foster its population expansion, which helps the species to overcome spatial isolation. The fact that each root fragment can develop into a new individual makes R. typhina very difficult to be eradicated once established. From a biological point of view, we believe that R. typhina is a plant invader in Beijing. We therefore suggest the government should remove the name of R. typhina from the main tree species list in afforesting Beijing.     

火炬树分泌道的发育解剖学研究

本文报道了火炬树分泌道的结构、分布和发育。火炬树的分泌道是由一层分泌细胞及其外侧1—5层薄壁组织细胞组成的鞘细胞所包围。分泌道主要分布于根、茎、叶、花和果实的维管束的韧皮部内,此外,在茎的髓部也存在散生的分泌道。各类器官中的分泌道都以裂生方式发育;营养器官中的分泌道先于维管分子分化,生殖器官中的则后于维管分子的分化。     

火炬树抗螨性生物测定

本文分别测定了二斑叶螨Tetranychus urticae Koch和山楂叶螨Tetranychus viennensis Zacher对火炬树的选择性,以及限制性条件下火炬树对叶螨的生存及产卵的影响。结果表明：在火炬树叶和苹果叶之间,二斑叶螨和山楂叶螨在2 h, 6 h, 10 h, 12 h对火炬树的选择率分别为9.5%, 6.5%,5%,5%和2%,5%,1%和0,显著低于对苹果的选择率。被限制于火炬树叶上生存的山楂叶螨144 h后死亡率100%,产卵力随生存时间增加而下降,至96 h后产卵终止; 被限制于火炬树叶上生存的二斑叶螨240 h后全部死亡,整个观察期内（24～216 h）始终没有产卵。据此认为： 叶螨强烈拒食火炬树,火炬树对叶螨具有生存、产卵抑制作用,但这种抑制作用呈现种间差异。     

Dispersal modes affect tropical forest assembly across trophic levels

We examined assemblages of trees and two major groups of vertebrate seed dispersers, birds and primates, in Ugandan protected areas to evaluate the roles of dispersal limitation and species sorting in community assembly. We conducted partial Mantel tests to investigate relationships between community similarity, environmental distance and geographic distance. Results showed that environmental factors, specifically temperature and rainfall, significantly and more strongly structured tree assemblages than geographic distance. Analysis of tree dispersal modes revealed wind‐dispersed tree guilds were significantly dispersal limited but trees dispersed by animals were not. For assemblages of vertebrate seed dispersers, dispersal limitation significantly and more strongly structured assemblages of primates than species sorting whereas environmental factors significantly and more strongly structured assemblages of birds than dispersal limitation. We therefore examined whether trees dispersed by primates were more dispersal limited than trees dispersed by birds. We found consistent trends that primate fruit trees were more dispersal limited than bird fruit trees using three definitions of dispersal syndromes based on fruit color. Our results suggest that the dispersal abilities of primary consumers may affect the distribution of primary producers at large spatial scales.     

南京中山植物园秋冬季鸟类对植物种子的传播作用

1999年10月20日－2000年1月20日,在南京中山植物园内随机收集鸟粪样品160份,共分离出874粒结构完整的种子和果核、3块鞘翅目昆虫残体和1块鸟类羽毛残块。已鉴定出842粒种子和果核,分属于16科20属26种（变种）。在鸟粪样品中出现频率较高的种子依次分别属于冬青（Ilex purpurea)(22.22%)、圆柏（Sabina chinensis)(11.11%)、盐肤木（Rhus chinensis)(10.63%)、朴树（Celtis sinensis)(9．18％）、爬山虎（Parthenocissus tricuspidata)(7.73%)、龙柏（S.chinensis cv.kaizuca)(7.25%)等;种子数量相对较多的植物种类主要有冬青（23．52％）、盐肤木（16．15％）、圆柏（13．54％）、爬山虎（7．96％）、龙柏（7．96％）、小果蔷薇（Rosa cymosa)(5.34%)等。除经鸟粪传播外,鸟类还通过衔取果实以及在吞食果实后将种子呕出的方式传播种子。初步发芽试验表明,鸟粪样品中的爬山虎、盐肤木的种子,以及被鸟呕出的樟树（Cinnamomum camphora)、楝树（Melia azedarach)的种子均可发芽出苗。鸟类传播种子使南京中山植物园内樟树、冬青、海桐（Pittosporum tobira)和红豆杉（Taxus chinensis)等栽培树种成功地侵入到位于植物园北缘的虎山山坡黑松（Pinus thunbergii)、枫香（Liquidambar formosana)群落、以及植物园内山溪边的枫杨（Pterocarya stenoptera)、朴树群落等生境中。鸟类对种子的传播作用扩大了南京中山植物园内那些具有肉质果实、种子具有坚硬种皮或种子包被于坚硬果核中的植物种类的分布范围,促进了它们的自然更新。     

北京市居住区林木健康评价

为了揭示北京市居住区林木健康变化特征及影响因素,提供北京市居住区林木健康经营对策。对北京市85个居住区林木进行健康特征调查,在建立林木健康评价模型评价林木健康状况的基础上,采用方差分析法和多重比较法分析不同类型居住区林木健康差异。结果表明:不同类型居住区林木健康指标差异显著(P0.05),各指标变化规律不完全一致;不同类型居住区地表覆盖情况、光污染程度、树干倾斜度、栽植截干、树势、冠形、干形等方面普遍较差。北京市居住区林木健康指数在0.60—0.80之间,健康等级呈现右偏正态分布特点,健康林木比例为3. 65%,亚健康林木(56. 07%)最多,其次是中等健康林木(36.68%),不健康林木有3.50%,濒死林木仅占0.10%。居住区林木健康指数在不同区域和不同来源间差异不显著(P0.05),在不同时期间差异显著(P0.05),健康指数大小分别为:三—四环=四—五环五—六环二环内=二—三环;福利房商品房保障房;2009—2013年2003—2008年=1998—2002年=1991—1997年1956—1990年。北京市居住区林木生长处于亚健康状态,潜在影响因子如地表覆盖情况、光污染程度、树干倾斜度等指标是限制北京市居住区林木生长的重要因子。适当减小夜间照明影响、增加有机地表覆盖、避免过度的修枝截干和加强林木养护管理是当前北京市居住区林木健康生长的保障。     

Patterns of Seed Dispersal and Dispersal Failure in a Hawaiian Dry Forest Having Only Introduced Birds

Dry forests are among the most endangered natural communities in the Hawaiian Islands. Most have been reduced to isolated trees and small forest fragments in which native tree species reproduce poorly. The replacement of native birds by introduced generalists may be contributing to dry forest decline through modification of seed dispersal patterns. To document seed dispersal by introduced birds, we conducted foraging observations on fleshy-fruited trees and measured seed rain under trees and in adjacent open areas for 1 year in a dry forest dominated by native trees. Although trees covered only 15.2 percent of the study area, 96.9 percent of the bird-dispersed seeds were deposited beneath them. The Japanese white-eye (Zosterops japonicus) was the principal dispersal agent. Among bird-dispersed seeds, those of the invasive tree Bocconia frutescens accounted for 75 percent of all seeds collected beneath trees (14.8 seeds/m²/yr) and the invasive shrub Lantana camara accounted for 17 percent. Although nearly 60 percent of the reserve's native woody species possess fleshy fruits, introduced birds rarely disperse their seeds. Native trees accounted for <8 percent of all bird-dispersed seeds and are consequently experiencing dispersal failure by falling directly under parent trees. Smaller-seeded non-native plants, in contrast, may be benefiting from dispersal by introduced birds. Current dispersal patterns suggest that these readily disseminated non-native plants may eventually replace the remaining native flora.     

Exploring the interaction of avian frugivory and plant spatial heterogeneity and its effect on seed dispersal kernels using a simulation model

Seed dispersal by avian frugivores is one of the key processes influencing plant spatial patterns, but may fail if there is disruption of plant–frugivore mutualisms, such as decline in abundance of dispersers, fragmentation of habitat, or isolation of individual trees. We used simulation model experiments to examine the interaction between frugivore density and behaviour and the spatial arrangement of fruiting plants and its effect on seed dispersal kernels. We focussed on two New Zealand canopy tree species that produce large fruits and are dispersed predominantly by one avian frugivore (Hemiphaga novaeseelandiae). Although the mean seed dispersal distance decreased when trees became more aggregated, there were more frugivore flights between tree clusters, consequently stretching the tails of the dispersal kernels. Conversely, when trees were less aggregated in the landscape, mean dispersal distances increased because seeds were deposited over larger areas, but the kernels had shorter tails. While there were no statistically meaningful changes in kernel parameters when frugivore density changed, decreases in density did cause a proportional reduction in the total number of dispersed seeds. However, birds were forced to move further when fruit availability and fruit ripening were low. Sensitivity analysis showed that dispersal kernels were primarily influenced by the model parameters relating to disperser behaviour, especially those determining attractiveness based on distance to candidate fruiting trees. Our results suggest that the spatial arrangement of plants plays an important role in seed dispersal processes – although tree aggregation curbed the mean seed dispersal distance, it was accompanied by occasional long distance events, and tree dispersion caused an increase in mean dispersal distance, both potentially increasing the probability of seeds finding suitable habitats for germination and growth. Even though low frugivore densities did not cause dispersal failure, there were negative effects on the quantity of seed dispersal because fewer seeds were dispersed.     

Scale‐dependent effects of forest restoration on Neotropical fruit bats

Neotropical fruit bats (family Phyllostomidae) facilitate forest regeneration on degraded lands by dispersing shrub and tree seeds. Accordingly, if fruit bats can be attracted to restoration sites, seed dispersal could be enhanced. We surveyed bat communities at 10 sites in southern Costa Rica to evaluate whether restoration treatments attracted more fruit bats if trees were planted on degraded farmlands in plantations or island configurations versus natural regeneration. We also compared the relative influence of tree cover at local and landscape spatial scales on bat abundances. We captured 68% more fruit bat individuals in tree plantations as in controls, whereas tree island plots were intermediate. Bat activity also responded to landscape tree cover within a 200‐m radius of restoration plots, with greater abundance but lower species richness in deforested landscapes. Fruit bat captures in controls and tree island plots declined with increasing landscape tree cover, but captures in plantations were relatively constant. Individual species responded differentially to tree cover measured at different spatial scales. We attribute restoration effects primarily to habitat structure rather than food resources because no planted trees produced fruits regularly eaten by bats. The magnitude of tree planting effects on fruit bats was less than previous studies have found for frugivorous birds, suggesting that bats may play a particularly important role in dispersing seeds in heavily deforested and naturally regenerating areas. Nonetheless, our results show that larger tree plantations in more intact landscapes are more likely to attract diverse fruit bats, potentially enhancing seed dispersal.     

Directed seed dispersal towards areas with low conspecific tree density by a scatter‐hoarding rodent

Scatter‐hoarding animals spread out cached seeds to reduce density‐dependent theft of their food reserves. This behaviour could lead to directed dispersal into areas with lower densities of conspecific trees, where seed and seedling survival are higher, and could profoundly affect the spatial structure of plant communities. We tested this hypothesis with Central American agoutis and Astrocaryum standleyanum palm seeds on Barro Colorado Island, Panama. We radio‐tracked seeds as they were cached and re‐cached by agoutis, calculated the density of adult Astrocaryum trees surrounding each cache, and tested whether the observed number of trees around seed caches declined more than expected under random dispersal. Seedling establishment success was negatively dependent on seed density, and agoutis carried seeds towards locations with lower conspecific tree densities, thus facilitating the escape of seeds from natural enemies. This behaviour may be a widespread mechanism leading to highly effective seed dispersal by scatter‐hoarding animals.