Current Status and Advancements in Research of Plantation Nutrient Cycling

Nutrient cycling refers to the complicated process of cycling, transferring, changing of mineral and chemical elements in the eco-system, which is one of the most fundamental functions of eco-system. Some of the nutrients mainly circulate among organisms and atmosphere; others mainly circulate among organisms and soil, or among organisms, atmosphere and soil. In short, there are three types of circulations of nutrient cycling in ecosystem: geochemical cycles, biogeochemical cycles and bio- che…     

南峪口铁矿生态影响评价中的植物物种多样性分析

在植被现状调查的基础上,采用物种多样性指数法,对南峪口铁矿生态影响评价的植物物种多样性进行了比较,结果表明：该矿的植被可划分为8个群落类型,反映了矿区不同功能区的植物群落主要类型。根据物种多样性指数的计算结果,不同功能区的植物物种多样性表现出明显差异,按照物种多样性指数大小排序：矿界外评价区＞矿区非开采区＞拟选废石场＞相邻矿区＞工业场地＞炸药库＞铁矿开采区,反映了铁矿开采活动对周边环境干扰程度的差异性。     

东莞市绿道网大岭山森林公园段生态景观林带树种组成及群落特征调查分析

对广东省东莞市绿道网大岭山森林公园段生态景观林带树种组成及群落特征进行调查研究,7种类型的样地调查结果表明:(1)主要乔木优势种为:人面子、大花紫薇、深山含笑、山杜英、木棉等。灌木优势种为灰莉、九里香、山瑞香、金脉爵床、红花檵木、红绒球等;(2)乔木层平均树高为6.40 m,最大值为11.0 m,为木荷,其它依次为铁刀木(10.9 m)、仪花(10.2 m)、木棉(9.8 m);(3)乔木层的H(Shannon-Wie-ner指数)、D(Simpson指数)、J(均匀度指数Evenness)分别为1.72、0.78、0.87;H最大值为2.10,出现在样地7;D最大值为0.83,出现在样地7;J最大值为0.90,出现在样地2、样地4、样地5。     

东莞市生态景观林林分改造效果研究

对广东省东莞市大岭山森林公园低效相思类林分进行改造,4．5a生时采用样方法进行林分生态效益和景观效益的调查。结果表明：（1）选用的红锥、樟树、山苍子等几个树种生长表现最好,高、径生长都较快,其中红锥、樟树的表现尤其优秀;（2）改造后的林分草本层物种达到了3．8—9．4种,平均为6．33种;多样性指数为0．80～1．92,平均为1．39;均匀度指数为0．61～0．87,平均为0．77;生态优势度0．30～0．58,平均为0．35,林分整体生物多样性较好;（3）林地表层土壤（0～25em）疏松,持水能力较强。林分最大持水深15mm,其中林地土壤占98．24％。（4）在相思林下用2年生苗木进行套种改造,采用较高的造林措施,可以在2—3年内形成景观效果,林分复层林冠基本成型,林相有初步的季节变化。     

Relationship between species diversity and biomass of eucalyptus plantation in Guangxi, south China

To reveal the relationship between species diversity and biomass in a eucalyptus (Eucalyptus urophylla × E. grandis) plantation located in the Dongmen State Forestry Farm of Guangxi, south China, 18 sample plots were established and the total biomass, arbor layer biomass and undergrowth biomass of communities were subsequently harvested. The results were as follows: 1) Species richness in eucalypt plantation had remarkable positive correlation with biomass of arbor layer, undergrowth and community (α = 0.001), its correlation coefficients were 0.6935, 0.7028 and 0.7106 respectively. 2) Leaf area index (LAI) had remarkable positive correlation with species richness and undergrowth biomass (α = 0.001). Its correlation coefficients were 0.7310 and 0.6856, respectively. 3) Arbor layer biomass had remarkable correlation with soil organic matter and hydrolysable N, its correlation coefficients was 0.6416 and 0.6203 respectively. Species richness had remarkable correlation with soil organic matter and correlation coefficient was 0.6359. Among them, the correlation was significant at the 0.1 level. Undergrowth biomass had little correlation with nine soil nutrients and correlation coefficients were under 0.4. To sum up, species diversity was advantageous to the promotion of the biomass of the eucalyptus plantation, and the variation of LAI and soil nutrient in small-scales could result in the difference of species diversity and biomass in different sample plots. Translater from Scientia Silvae Sinicae, 2008, 44(4): 14–19 [译自: 林业科学]     

惠州市生态公益林乡土树种筛选试验

比较了广东省博罗县梅花林场11种8年生乡土树种的生长状况,并应用样方法调查分析了林分的物种多样性。结果表明,白楸(Mallotus paniculatus)、红苞木(Rhodoleia championii)、红锥(Castanopsis hystrix)和火力楠(Michelia macclurei)生长较快;大头茶(Gordonia axillaris)、柳叶桢楠(Machilus salicina)和拐枣(Hovenia dulcis)生长较慢。与造林初期相比,改造后8年生的林分物种多样性和均匀度稍有下降。研究表明,白楸、红苞木、红锥和火力楠均适合作为惠州市生态公益林和风景林的树种。     

Carbon, water and nutrient flux in Maya homegardens in the Yucatán peninsula of México

The Yucatán Peninsula of México has shallow soils and receives low amounts of precipitation, and has therefore low agricultural potential. Lacking large-scale irrigation from rivers and adequate rainfall, the indigenous Maya groups maintain agricultural productivity by adapting a variety of practices. Multistrata homegardens, one of their agricultural systems, have provided goods for trade, sale and personal consumption for many centuries. Nevertheless, an understanding of the controlling biological factors and interactions within these systems can lead to yield improvements. Photosynthetic rates, water use and litter production for a variety of species have been studied in these gardens to determine how Maya management impacts resource flow, productivity and diversity. When irrigated, diurnal photosynthetic rates nearly doubled for Manilkara zapota and water use increased two fold for M. zapota and Cordia dodecandra. Total litter production in traditional homegardens varied from 1,000 to 4,000 kg ha⁻¹ yr⁻¹ and ten arboreal species were found to contribute more than 33% of total litterfall biomass. Nutrient concentrations in the leaves of the predominant species were analyzed; Meliococcusbijugatus and Spondias purpurea were found to contribute the largest quantities of N, P and C. Our research indicates that species and structural diversity are critical to sustainability of homegardens, allowing efficient use and transfer of carbon, nutrients and water. This revised version was published online in June 2006 with corrections to the Cover Date.     

海南岛中部山区自然植被演变阶段物种多样性分析

运用α和β物种多样性指数分析热带地区海南中部山区草地、灌丛、次生林和原始林植被演替过程中物种多样性变化规律。结果表明,物种丰富度指数、Margalef's指数和Shannon-Wiener指数能较好地反映不同演替阶段间的物种多样性大小差异;而Alatalo均匀度指数能较好反映物种分布变化。从草地到原始林阶段,群落α物种多样性呈连续增大趋势。Jac-card和Srenson相异性指数能较好地反映不同演替阶段群落间的物种更替,且呈单峰曲线变化,在灌丛与次生林过渡阶段最大。     

杉木人工林择伐5年后生态效果综合分析

对杉木(Cunninghamia lanceotata(Lamb.)Hook.)人工林进行4种不同强度择伐作业,分别为弱度12.9%、中度23.5%、强度46.1%和极强度64.6%,分析不同强度择伐5 a后对植被、土壤和凋落物的影响。结果表明:与未采伐相比,林分平均树高、平均胸径、蓄积量和断面积均随择伐强度增大呈先增大后减小的趋势;林下灌木和草本的物种多样性指数均增大;0~20 cm土层土壤密度、水分、孔隙状况和养分状况,均得到一定程度的改善;强度择伐下林地凋落物现存量及其养分总量均最大。综合比较得出,强度择伐5 a后林地生态环境的综合改善效果较佳,更适宜南方山地杉木人工林的科学经营与管理。     

亚热带常绿阔叶林结构、树种多样性和土壤特性的研究(英文)

采用样地调查法,对日本冲绳岛北部的亚热带常绿阔叶林的林分结构,树种组成以及土壤特性等进行了调查分析。结果表明,该亚热带林具有林冠低矮、小径木多等特点。林分的平均林冠高度仅10m,平均立木密度达5400株·hm2(≥3.0cmDBH),其中胸径小于10cm的立木占64%。林分胸高断面积为54.4m2·hm-2。30个调查样地共出现树种数(≥3.0cmDBH)达80种,分属31个科。根据树种的重要值,Castanopsis sieboldii和Schima wallichii分别为优势树种和亚优势树种。树种多样性指数(H’)平均达3.63,均衡度指数(J’)为0.71,丰富度指数(S’)为4.72。这些多样性指数都随着优势树种重要值的增加而显著降低。土壤养分测定结果表明,该森林的土壤肥力低,异质性大,并可能存在Al毒害。由相关分析知,林分密度和优势树高均与土壤pH值呈显著正相关关系;多样性指数则与土壤交换性K ,Ca2 以及Ca2 /Al3 比呈显著的正相关,而与土壤有机碳,全氮和磷呈显著的负相关。这些结果说明土壤性质是影响冲绳亚热带常绿阔叶林林分结构和树种组成多样性的重要因素。图3表4参38。     

钱塘江流域森林群落物种多样性与土壤因子的关系

对钱塘江流域不同林分的4个物种多样性指数和9个土壤指标进行回归分析。结果表明:全磷、速效钾与乔木层各指数有显著负相关关系(P<0.05),有效磷与乔木层Simpson指数有显著负相关关系(P<0.05),水解性氮与草本层Shannon-Wiener指数、Gleason指数有显著正相关关系(P<0.05),速效钾与草本层Gleason指数有显著正相关关系(P<0.05);逐步回归分析表明,土壤全磷、速效钾对钱塘江流域植被物种多样性影响较大。     

The role of indigenous trees for the conservation of biocultural diversity in traditional agroforestry land use systems: The Bungoma case study: In-situ conservation of indigenous tree species

In order to precisely assess the role of agroforestry for the conservation of (agro-)biological diversity there is a need to adjust sampling methods used in plant sociology. This study is on the contribution of agroforestry land use to the in-situ conservation of indigenous trees within a typical East-African smallholder farming system in Western Kenya. A modified approach to measuring species richness and abundance is presented. The selection of tree-rich structures was done according to management patterns rather than considering syntaxonomic classifications from the vegetation science point of view. This approach, which is better suited to the strongly human-influenced vegetation of agroecosystems, employs between-management unit diversity measures to help evaluate abundance and constancy of species in particular management units. The predominant off-farm vegetation patterns are riverine forests, rocky hillsides, hedgerows, wooded grassland relicts, woodlands or colline forest relicts and tree groves whereas the noticeable tree-rich on-farm management units are homegardens, homesteads, life fences, coffee- and banana-groves and annual cropping fields. 98% out of all indigenous tree species known from Bungoma, occur in off-farm lands. 53% of the indigenous tree species occur in tree rich on-farm management units while 47% of the indigenous trees are dependent on the maintenance of off-farm lands. Hedgerows embody the most promising secondary vegetation structure that shows ample potential to accommodate a wide range of indigenous perennial species outside the natural vegetation formations. The pattern of distribution of various vegetation structures, and the mixture with diverse tree-based on-farm plots are interesting features in regard to floristic and eco-diversity on a landscape level. In this respect, three areas that show different population densities and distinct agro-historical conditions were compared. In regions of particular high population density the degree of association of various functional land use forms and woodland structures – each characterised by its own floristic make-up – is comparatively high. In contrast, in regions with less population but that were settled at a later date, one encounters fewer stands of woody plants with lower numbers of species. This revised version was published online in June 2006 with corrections to the Cover Date.     

粤北英西峰林走廊传统村落大岩村人居环境特色

粤北英西峰林走廊地区为典型的喀斯特地貌,且由于历史的移民迁徙分布着诸多传统村落。选取粤北英德市黄花镇大岩村为例,通过实地调研和设计分析的方法,立足于喀斯特地区的地域特性,对大岩村的村落选址、村落布局、景观环境经营进行分析。认为大岩村的人居环境存在以下特色:在选址上背山面田,村落与山体形成轴线关系;村落布局贴山延展,生产生活关系紧密;在庭园空间的营造上巧于借自然之景。     

桉树人工林养分循环研究成果分析

本文主要介绍了桉树人工林养分循环的意义与研究现状。从地球化学循环和生物小循环（养分含量、养分积累和分布、凋落物、养分循环特征）两方面阐述桉树人工林养分循环的研究内容,分析说明桉树人工林养分循环研究存在的问题及发展趋势,并提出几点建议。     

广东典型低效生态公益林植物群落结构及物种多样性

基于广东省典型低效生态公益林林分类型——马尾松纯林、杉木纯林及针阔混交林群落的样方调查,分别对其物种组成、区系成分、植被结构特征、物种丰富度和多样性进行了研究。结果表明：在18个调查样方中,共记录到维管束植物58科 92属149种,热带亚热带区系特征明显;几种典型低效生态公益林群落垂直结构都相对简单,均尚处于植被演替的较早期阶段;物种丰富度指数为32～66,Shannon Wiener多样性指数值为0.61～3.15,Simpson优势度指数值为0.26～0.89,以及均匀度指数值为0.15～0.89。文章初步探讨了影响生态公益林植物多样性的主要因素和提高不同类型低效生态公益林植物多样性的途径。     

Changing livelihoods on the slopes of Mt. Kilimanjaro,Tanzania: Challenges and opportunities in the Chagga homegarden system

Mt. Kilimanjaro area with the old Chagga agroforestry system has been one of the most productive agricultural areas is Tanzania. Today the area is facing several challenges that affect people’s livelihoods. To study implications of low coffee price, population pressure and ensuing land use change on the farming systems and livelihoods of the people of the southern slopes of Mt. Kilimanjaro, Tanzania, an interview survey was conducted. A multivariate regression analysis was used in studying and testing the interrelationships between farm production and some socio-economic variables (assets). From nine different independent variables only land size and farmers age had statistically significant influence on revenue from the main crops grown. This suggests that families have so many different combinations of assets and farm-specific temporally varying strategies and objectives that it is not possible to find clear patterns of assets and strategies that would lead to successful livelihood outcomes. Due to sinking coffee prices in the world market, farmers have been looking for alternatives to earn cash. As land scarcity hinders both expansion of cultivation and expansion of animal keeping, more intensified and diversified production and off-farm activities have become crucial. There is an urgent need for technical research and experimentation on new agricultural options for the area and a need of understanding and creation of marketing channels.     

湖南湖北藤本植物物种多样性和生态特征

对湖南、湖北藤本植物的分类群起源、生活习性、攀援方式、繁育系统几个方面进行系统分析.结果表明:研究区藤本种子植物60科159属784种(含变种),分别占本区种子植物的29.7%、10.8%和11.1%;在全部含藤本植物的科属中,含10个种以下的科、属分别占总科数、总属数的68.3%和89.9%;藤本种类的数量主要集中在少数几个大科或大属中, 葡萄科和猕猴桃科等11个大科占有总种数的64.8%;攀援方式分为5大类,12小类,缠绕类最多,占48.7%,卷曲类23.2%,搭靠类16.5%,吸固类6.0%,混合类5.6%;两性花类67.3%,杂性花类5.1%,单性花27.5%,雌雄异株种数多于雌雄同株.     

大黑山生态修复区典型植物群落物种多样性变化特征分析

以大黑山水土保持生态修复工程示范区为研究区域,运用典型植物群落物种组成和群落物种多样性指数方法,对大黑山水土保持生态修复区典型植物群落物种多样性变化特征进行了研究,结果表明,生态修复区内天然次生林植物群落形成了乔灌草相结合的稳定的植物群落结构。人工林植物群落按生长型可以划为明显的乔木层和草本层2层群落结构类型;典型植物群落物种多样性指数的排序为:蒙古栎+蒙椴植物群落(Ⅱ)>山杏+黄榆植物群落(Ⅰ)>蒙古栎植物群落(Ⅲ)>油松+山杏混交植物群落(Ⅴ)>油松纯林植物群落(Ⅳ)>油松+沙棘混交植物群落(Ⅵ)>油松疏林植物群落(Ⅶ)。天然次生林植物群落的物种多样性要大于人工林植物群落。天然次生林植物群落由于远离人类活动区,长期以来受人为干扰较小,逐渐形成了相对比较发达的草本层植物群落。     

Effects of thinning on nutrient content pools in two Pinus sylvestris forests in the western Pyrenees

Abstract

Nutrient content [nitrogen (N), phosphorus (P), potassium (K), calcium (Ca) and magnesium (Mg)] in needles, branches and stems before (P0, not thinned) and after thinning (P20 and P30, 20% and 30% of basal area removed, respectively) was studied in 37- and 32-year-old Pinus sylvestris L. forests in the western Pyrenees: Garde and Aspurz. Thinning significantly decreased all nutrient pools in P20 and P30 relative to P0 on both sites, but no significant differences were found between P20 and P30 owing to low statistical power. Thinning increased the differences between the two forests for total above-ground content of P and Mg, and for the content of N, P and K in the 1999 needles cohort. The former result was due in part to the higher concentration of P (needles and branches) and Mg (needles) in Garde. Therefore, the importance of needles relative to the other nutrient pools increased for N and P after thinning. This may have resulted from the fact that the removal of dead trees with low needle biomass was greater in Garde than in Aspurz. Based on the percentage of basal area removed, nutrient removal in Garde for P30 was higher than expected, apparently owing to an increase in branch removal relative to P20. These results indicate that effects of thinning on nutrient pools were influenced by differences in stand structure and nutrient tissue concentrations between sites.