不同处理对蒙古扁桃种子吸水及幼苗生长影响

通过对蒙古扁桃种子吸水过程、幼苗生长的观测,拟合了种子的吸水模型,分析了幼苗生物量的差异.结果表明:蒙古扁桃种子吸水过程适合对数函数曲线模型,吸水率分别适合幂函数、对数函数曲线模型;50℃温水处理水平可以有效地提高带内果皮种子的吸水量和吸水速度,不带内果皮种子经过温水处理后9 h、吸水量为6.3%时种子吸水量即基本达到饱和;种子在1 h内能够大量吸水,适应荒漠强降雨环境;内果皮能够吸收一定的水分,在环境干旱时可以减轻环境干旱造成的种子失水;幼苗地上部分生物量大于地下部分,带内果皮种子育苗能够有效地增加幼苗高度和根系长度.     

濒危树种极东锦鸡儿(Caragana fruticosa)种子的萌发特性

以濒危树种极东锦鸡儿成熟种子为材料,研究极东锦鸡儿种子物理性状和温度对其种子萌发及幼苗生长的影响。结果表明:极东锦鸡儿种荚结实率较低,且约有1/4种子受虫害;成熟种子含水量为6.6%,千粒重18.6 g。种子长、宽和厚存在一定变异。种子长度平均为0.42 cm,宽度平均为0.27 cm,厚度平均为0.24 cm,长宽比为0.64。种皮透水性良好。不同温度条件对种子发芽率具有极显著影响。25℃条件下种子发芽率最高,为38.33%。随着温度的升高或降低,种子发芽率降低。发芽试验的第八天是计算种子发芽势的适宜时期。不同温度条件对极东锦鸡儿幼苗高度的影响极显著,对胚根长度影响显著。25℃有利于幼苗高度和胚根长度的增加,较高温度(30℃)有利于幼苗生物量增加。     

诃子果核处理对发芽的影响试验

采用不同方法处理诃子果核并作发芽试验,结果表明:去内果皮种子的发芽效果最好,其室内发芽率达到82.4%,平均发芽时间为4.6d,发芽历时10d,发芽盛期为第4d;苗圃发芽率为59.2%,平均发芽时间为9.7d,发芽历时30d,发芽盛期为第7d;而带内果皮的各种处理方法的发芽效果均不理想。本文还对诃子去内果皮技术和芽苗移植技术进行探讨。     

柄扁桃内果皮提取液对小麦种子萌发和幼苗生长的影响

用柄扁桃内果皮不同浓度的提取液对小麦种子进行生物活性测定,结果表明柄扁桃内果皮提取液可显著抑制幼苗叶绿素的合成,并对种子萌发过程中的抗氧化酶活性有影响。本研究首次证明柄扁桃内果皮中存在活性较强的抑制物,且易溶于水和乙醚。     

珍稀濒危树种银缕梅种子萌发特性研究

在测定银缕梅(Parrotia subaequalis)种子形态和千粒重的同时,研究了不同储藏方式、温度、赤霉素处理、光照条件对种子萌发的影响.结果表明:银缕梅种子呈长纺锤形,平均长径8.08 mm,平均短径3.79 mm,千粒重46.35 g；储藏方式对银缕梅种子的萌发影响较大,其次为温度,赤霉素浓度对种子发芽率的影响较小,种子萌发的最佳处理组合为常温沙藏、赤霉素浓度600 mg/L、温度20～25℃,发芽率达73.73％；适度光照可缩短种子发芽时间,提高发芽势.     

山杏种子后熟生理及萌发条件的研究

测定了去除内果皮的山杏种子不同温度浸水处理的吸水性、温度对去除胚尖处种皮和不去种皮种子萌发的影响；萌发过程中种子内可溶性糖含量的动态变化；激素对种子萌发的影响及萌发期间种子内ａ-淀粉酶活性和过氧化氢酶活性的变化。结果表明，５０℃低温浸种２４ｈ可达山杏萌发所需水分条件及活力指数；层积处理以２～５℃效果最好；ＧＡ３在适宜浓度下能打破休眠，促进种子发芽、茎根伸长和幼苗生长；种子萌发期间可溶性糖含量呈不断增加趋势，ａ-淀粉酶活性不断增强；层积后种子内ａ-淀粉酶活性显著增强。     

高盆樱桃种子萌发特性初探

高盆樱桃 Cerasus cerasoides 原生于西藏和云南地带,为我国唯一冬季开花的樱属树种。其树形优美,花色艳丽,造景效果好,目前多应用于云南地区的绿化及造林。为探索高盆樱桃种子的萌发特性,测定其长、宽、厚、百粒重、吸水特性、发芽特性以及芽苗质量指标,并初步探索种子大小对种子萌发的影响。结果表明：高盆樱桃种子浅褐色,呈卵圆状;平均长 10.56 mm,平均宽 7.89 mm,平均长宽比为 1.34,平均厚 6.06 mm,平均百粒重为 25.48 g;在培养皿铺纱布保湿的环境下种子发芽率为 42.67%;大种子发芽势、发芽率等数值均高于中、小种子,种子大小与发芽率呈正相关。     

育苗方式对3种扁桃植物成苗率与幼苗生长的影响

以蒙古扁桃(Amygdalus mongolica)、长柄扁桃(Amygdalus pedunculata)、四川扁桃(Amygdalus tangutica)种子为试验材料,采用穴盘、营养钵、大田3种方式进行播种育苗,通过比较3种扁桃在不同育苗方式下的生长特性,旨在筛选3种扁桃的最佳育苗方式,为其人工种植和推广应用提供依据。结果表明:(1)蒙古扁桃、四川扁桃在穴盘育苗中的出苗率最大,分别为92. 4%、88. 8%,长柄扁桃的出苗率仅为85. 8%。(2)蒙古扁桃、长柄扁桃的株高和地径分别在营养钵、大田育苗下有最大值,而四川扁桃的株高在营养钵育苗下显著高于穴盘132. 9%(P0. 05)。(3)相同育苗方式下,3种扁桃的地上生物量、地下生物量和总生物量均随育苗时间的延长显著增加;不同育苗方式下,蒙古扁桃的地上生物量、总生物量表现为:营养钵大田穴盘,四川扁桃的地下生物量和总生物量表现为:大田营养钵穴盘,长柄扁桃的地上生物量、地下生物量和总生物量均在营养钵育苗下有最大值。综合考虑经济和生态效益,在宁夏进行推广应用时,蒙古扁桃应以营养钵育苗为主,其它2种扁桃以大田育苗为主,营养钵育苗为辅。     

厚朴不同种源及家系种子性状的变异

研究厚朴自然分布区内8个省份19个种源的种子长、种子宽、种子厚、种子长宽比及种子百粒重等性状的变异及趋变模式.结果表明:种源间种子长、种子宽、种子厚、种子长宽比等性状的差异均达到极显著水平;种源内不同家系种子长、种子宽、种子厚等性状的差异也均达到极显著水平;种源间种子百粒重变异远远高于种源内家系间变异,前者种子百粒重变异幅度为14.147～24.547 g,后者种子百粒重变异幅度为15.003～17.357 g;种子宽、种子厚和种子百粒重等性状受积温和热量因子控制作用极为明显.     

固沙先锋植物沙米的生物学特征研究

以石羊河下游荒漠区的古浪明沙咀和民勤西沙窝为研究区,研究了沙米的形态结构特征、种子形态及其萌发特性等,结果表明:沙米植株冠幅大小、第1层侧枝数、根径、根深、根幅和最大根长与株高呈线性正相关关系;地上生物量、地下生物量和总生物量与株高呈二次曲线关系,达到显著正相关;沙米生物量中地上生物量占到绝大部分,地上部分生物量中以10～20 cm生物总量最大,各层生物量逐渐减少;沙米种子的大小、千粒质量、种子含水率在不同生态区域或不同年份之间差异显著;沙米种子自然萌发率不高,在黑暗条件下,可提高其发芽率。     

The productivity of salt marsh vegetation at Tollesbury,Essex, and Stiffkey,Norfolk, England

This study presents data on the biomass and net aerial primaryproductivity (NAPP) of two contrasting East Anglian salt marshes.One site was at Tollesbury, Essex where the marshes are of theestuarine type and are subject to marsh degradation and erosionwhile the other site was 130 km to the north at Stiffkey, Norfolkwhere the barrier-type marshes are still actively developing withno signs of erosion. The NAPP was determined by the method ofSmalley with quadrats being harvested monthly with replacement.At the lowest levels at Tollesbury there was Pioneer Marshwhich was dominated by a mixture of Salicornia spp. and Astertripolium. At higher levels at Tollesbury there was LowerMarsh which was dominated by a mixture of Atriplex portulacoides andPuccinellia maritima. Over the four years of the studyPuccinellia became the dominant species following a markeddecrease in the extent and vigour of Atriplex. At Stiffkey theMiddle Marsh was at a much higher level and the vegetation waspredominantly a short dense sward with Atriplex portulacoides,Puccinellia maritima and Limonium vulgare together with smallerquantities of Armeria maritima and Plantago maritima. The meanNAPPs over three years of the Pioneer and Lower Marsh atTollesbury (467 & 519 g m^-2 yr^-1respectively) were similar butin 1993 the NAPPs recorded at Tollesbury were higher than thoserecorded at Stiffkey (625 & 583 compared with 458 g m^-2yr^-1).Smalleys method is difficult to apply to communities wherespecies dominance is variable, especially when dominance isshared between species with markedly different growth patterns.The results for NAPP obtained from the salt marshes at Tollesburyand Stiffkey are discussed in relation to results obtained byother workers from comparable areas in England and theNetherlands. Attention is also drawn to the possibly largerbelow-ground component of production that is frequentlyoverlooked. The importance of salt marshes in relation to othercoastal communities lies in the export of a proportion of theorganic matter produced and this mainly depends on theabove-ground production.     

Responses of swamp bay,Persea palustris,and avocado,Persea americana,to various concentrations of the laurel wilt pathogen,Raffaelea lauricola

Laurel wilt, caused by the fungus Raffaelea lauricola and transmitted by the exotic ambrosia beetle Xyleborus glabratus, has killed members of the Lauraceae plant family throughout the southeast United States. A series of experiments were conducted to examine the effects of inoculum concentration on the development of laurel wilt in swamp bay, Persea palustris, and avocado, Persea americana. In each experiment, host plants were inoculated with aqueous suspensions of 10², 10³, 10⁴ or 10⁵ conidia of R. lauricola, and plants were rated periodically for external symptom development (wilting and foliar dieback). At the end of experiments, plants were rated for internal symptoms of the disease (discoloration of sapwood) and assayed for R. lauricola on a semi‐selective medium. Symptom severity in swamp bay was significantly lower for the 10² treatment than at higher (10³–10⁵) concentrations, whereas 10² and 10³ conidia caused less disease than 10⁴ and 10⁵ conidia in avocado. At the lowest inoculum concentration, 67% of the swamp bay plants and 20% of the avocados died by the time the respective experiments were terminated. The pathogen was recovered from a high proportion of the symptomatic sapwood of swamp bay (100%) and avocado (94%), and sapwood discoloration and recovery of R. lauricola from inoculated stems of swamp bay were highly correlated with recovery of the pathogen and symptom development in roots. Clearly, swamp bay and avocado are very sensitive to R. lauricola. The ability of only 100 conidia of this pathogen to kill these hosts suggests that few individuals of X. glabratus or other ambrosia beetles that carry low levels of the pathogen would be sufficient to transmit conidia that infect and lead to disease development. The results are also relevant to the development of disease‐tolerant host selections, as they indicate levels of the pathogen appropriate for use in screening plants for disease resistance.     

东莞蕨类植物区系研究

采用野外调查与查阅标本相结合的方法,对东莞蕨类植物区系及其分布特点进行研究,结果表明:东莞市有蕨类植物37科66属125种,其区系特点为:①分布区类型在科、属、种的水平上皆以热带、亚热带性质为主,占各自总数的64.87%、75.76%与61.60%。②科与属的分布区类型显示出东莞蕨类植物区系从热带向亚热带过渡的性质,与温带蕨类植物区系的联系较弱;在种的水平上,温带成分占总数的28.80%,呈现出热带蕨类植物区系向温带蕨类植物区系过渡的特点。③在种的水平上热带亚洲分布及东亚分布类型构成了东莞蕨类植物区系的主体,各占38.40%和20.80%。④与周边4个地区的比较中,与深圳的相似性为最高,与乐昌的相似性为最低;总体上,东莞蕨类植物区系与周围地区关系较为密切。     

Ethno-medico-biology of Bhadrak district, Odisha, India

We carried out an ethno-medico-biological investigation in the interior of Bhadrak district, Odisha, India to explore the therapeutic use of traditional plants/animals by local inhabitants. The villagers and rural people used plant and animal species as medicine. We recorded therapeutic use of 18 plant species of 13 families and 12 animal species of seven taxonomic categories. Different plant/animal parts like bark, leaf, flower, seed, stem, root, whole plant, oil, blood, milk, urine and flesh were reported as used in raw or cooked form against 17 specific diseases. Prominent diseases treated by plant/animal remedies were asthma, cardiovascular ailments, diabetes, epilepsy, jaundice, malaria, skin disorder and rheumatism. This study provides a better database for future studies.     

Plant communities, species diversity, richness, and regeneration of a traditionally managed coastal forest, Kenya

The Kenyan coastal forests make up one of the World 25 Biodiversity Hotspots. They consist of over 140 fragments (the majority with areas less than 0.5 km²) of the once extensive Zanzibar-Inhambane lowland moist forest. The over 60 known Mijikenda sacred Kaya forests and groves scattered along the coastal hinterland form the greater part of this ecosystem. The forests are of biological and cultural significance, and this has been recognized nationally and internationally, with some now listed as World Heritage Sites. The forests are protected by councils of Kaya elders who regulate use of their resources. Increasing human population and subsequent rise in demand for forest products and land for settlement has put a strain on these relic forests. Farm encroachment and extraction of forest products in different Kaya forests have affected the vegetation ecology at varying levels. This study investigated the spatial species distribution, association and regeneration potential of commonly utilized plants in one of these traditionally managed ecosystems. A modified nested plot method was used to collect data in the field.Using TWINSPAN multivariate, and indicator species analysis, two plant communities (Asteranthe and Bridelia) and an undifferentiated vegetation type were identified. Species association in Asteranthe consisted largely of forest dependant species, with a significant presence of woody climbers. It was comprised of two sub-communities namely Manilkara and Scorodophloeos. In contrast the second plant community, Bridelia, was dominated by light demanding species. It comprised one sub-community (Catunaregam) and a seral stage (Keetia). The species diversity and richness was higher in the Asteranthe community compared to Bridelia. Some of the forest species commonly utilized by the local people were observed to regenerate both in open and closed forest habitats while others had seedling recruitment confined to closed forest.Despite some coastal forests showing physiognomic similarity, detailed study shows intra-variation linked to topography, exposition, type and intensity of human perturbation both currently and in the distant past. Clearly, vegetation patterns of coastal forests of eastern Africa change at fairly short intervals.Recruitment of forest specialists is likely to decline if closed forests are opened up by farm encroachment, however their less specialized counterparts can pioneer in re-colonization of disturbed sites if conservation is strengthened. There is need to invigorate traditional management systems of forests with cultural significance by recognizing and giving increased legal mandates to the local custodians.     

鸭儿芹等五种森林蔬菜人工栽培技术研究

采用大棚设施栽培和林下仿生栽培方法对鸭儿芹、三脉紫菀、败酱、马兰和牛繁缕五种森林蔬菜进行人工栽培,结果表明在大棚设施条件下采用以5:1:4的锯木屑 猪粪 黄心土配制的人工基质栽培产量达4715kg/亩.年,比大棚设施条件下的土壤栽培和露地栽培产量高30.1%和87.3%;林下仿生栽培条件下的产量分别是露地遮阳网蔽荫和无遮阳网蔽荫对照的2.3倍和5.1倍。同时还对鸭儿芹等五种森林蔬菜人工栽培的经济效益做了分析。     

系统论述卫片色调与坡向、坡度、坡位、林分龄组、郁闭度的关系

当前 ,人类赖以生存的地球资源与环境面临越来越严重的威胁。如何迅速、宏观、准确、周期性监控资源和环境 ,已被各国和国际环境组织所重视 ,而卫星遥感就具有迅速、宏观、准确、周期性等特点 ,已被各国应用。内蒙古大兴安岭林业调查规划设计院于 1996年松岭林业局森林资源二类调查时就采用了这个先进的卫星遥感技术。现将影响卫片色调的坡向、坡度、坡位、林分龄组、郁闭度的五大因素进行系统研究 ,找出其相关规律 ,为今后的森林资源调查建立标志和目视判读解译标志提供理论依据