Distribution patterns of vegetation biomass and nutrients bio-cycle in alpine tundra ecosystem on Changbai Mountains, Northeast China

A study was conducted to test the correlation between biomass and elevation and the differences in concentration and storks of nutrients among five vegetation types （Felsenmeer alpine tundra vegetation-FA, Lithic alpine tundra vegetation-LA, Typical alpine tundra vegetation-TA, Meadow alpine tundra vegetation-MA, and Swamp alpine tundra vegetation-SA） on alpine tundra of Changbai Mountains, Jilin Province, China in growing seasons of 2003, 2004 and 2005. The biomass of 43 mono-species and soil nutrients in alpine tundra ecosystem were also investigated. Dominant species from Ericaceae （such as Rhododendron chrysanthum and Vaccinium jliginosum var. alpinum） were taken to analyze organ biomass distribution. Result showed that the biomass and elevation had a significant correlation （Biomass-237.3 in（Elevation） ＋494.36; R^2=0.8092; P〈0.05）. No significant differences were found in phosphorus and sulphur concentrations of roots, stems and leaves among the five vegetation types. There were significant differences in nitrogen and phosphorus stocks of roots, stems and leaves and in sulphur stock of stems and leaves among TA, MA, and SA vegetation types （p〈0.05）. The nutrient stock of five vegetations was averagely 72.46 kg.hm^-2, of which N, P, S were 48.55, 10.33 and 13.61 kg·hm^-2, respectively. Soil N and S concentrations in meadow alpine tundra soil type was significantly higher than those in other four soil types （Cold desert alpine tundra soil, Lithic alpine tundra soil, Peat alpine tundra soil, and Gray alpine tundra soil）. Phosphorous concentration in SA type was higher （p〈0.05） than in other types. Soil nutrient stock （0-20cm） was averagely 39.59 t.hm^-2, of which N, P, S were 23.74, 5.86, 9.99 t·hm^-2, respectively.     

Leaf litter and crop residue decomposition in ginkgo agroforestry systems in eastern China: Soil fauna diversity and abundance,microbial biomass and nutrient release

The response of soil fauna to the litter decomposition process has received considerable attention,but this effect has not been fully examined in agroforestry systems.A 1-year in situ decomposition experiment was carried out in a pure ginkgo plantation and two ginkgo agroforestry systems using a litterbag method(11 different treatments were tested in three systems).We found that the application of different organic materials(crop residues)produced positive effects on the number of soil fauna in the ginkgo planting systems;the mixture of ginkgo leaves and corn leaves was the best performing treatment.Collembola and Acarina were the predominant groups in the litter bags and were mainly responsible for the differences among the treatments.Litter mixing promoted the abundance,richness,and diversity of soil fauna,and significant differences regarding the Shannon–Wiener index of the soil fauna were observed among the 11 treatments in July.Significantly higher soil MBC(microbial biomass carbon)and MBN(microbial biomass nitrogen)were observed in agroforestry systems than in pure ginkgo plantations.These results suggest that the practice of intercrop residue application plays an important role in enhancing soil ecosystem function in ginkgo agroforestry systems and may ultimately contribute to sustainable intercrop production,soil fertility,and local economic diversity.     

Effects of environmental factors on species richness patterns of herb layer in Eastern Zhongtiao Mountain

The species richness of herb layer was investigated among 43 plots of forest vegetation in the eastern Zhongtiao Mountain, in southern Shanxi Province, China. The forest vegetation was divided into two major vegetation types such as the deciduous forest and the coniferous forest by the two-way indicator species analysis （TWINSPAN）. The species richness of herb layer was fitted in the topographic and soil feature factors, as well as the topographic relative moisture index （TRMI） by the generalized linear models （GLM）. The results showed that canopy cover and altitude were the most significant environmental factors. Soil pH value and soil nutrients index such as total N, organic matter content had no significant influence. The effect of environment factors on species richness of herb layer had significant difference in vegetation types. For the broad-leaved forest, litter depth and TRMI were the important environment factors. For the coniferous forest, soil clay content was another important environment factor. The range of environmental gradient such as altitude may contribute to the difference.     

Above and below ground organic carbon stocks in a sub-tropical Pinus roxburghii Sargent forest of the Garhwal Himalayas

Accurate estimates of tree carbon,forest floor carbon and organic carbon in forest soils (SOC) are important in order to determine their contribution to global carbon (C) stocks.However,information about these carbon stocks is lacking.Some studies have investigated regional and continental scale patterns of carbon stocks in forest ecosystems;however,the changes in C storage in different components (vegetation,forest floor and soil) as a function of elevation in forest ecosystems remain poorly understood.In this study,we estimate C stocks of vegetation,forest floor and soils of a Pinus roxburghii Sargent forest in the Garhwal Himalayas along a gradient to quantify changes in carbon stock due to differences in elevation at three sites.The biomass of the vegetation changes drastically with increasing elevation among the three sites.The above-ground biomass (AGB) and below-ground biomass (BGB) were highest at site Ⅰ (184.46 and 46.386 t·ha-1 respectively) at an elevation of 1300 m followed by siteⅡ (173.99 and 44.057 t·ha-1 AGB and BGB respectively) at 1400 m and the lowest AGB and BGB were estimated at site Ⅲ(161.72 and 41.301 t·ha-1) at 1500 m.The trend for SOC stock was similar to that of biomass.Our results suggest that carbon storage (in both soil and biomass) is negatively correlated with elevation.     

Effect of abiotic factors on understory community structures in moist deciduous forests of northern India

Understory vegetation controls, in a significant way, the regeneration of overstory trees, carbon sequestration and nutrient retention in tropical forests. Development and organization of understory vegetation depend 3n climate, edaphic and biotic factors which are not well correlated with plant community structures. This study aimed to ~xplore the relationships between understory vegetation and abiotic factors in natural and planted forest ecosystems. A non-metric multidimensional scaling （NMS） ordination technique was applied to represent forest understory vegetation among five forest communities, i.e., a dry miscellaneous forest （DMF）, a sal mixed forest （SMF）, a teak plantation （TP）, a low-land miscellaneous forest （LMF） and a savanna area （SAV） of the Katerniaghat Wildlife Sanctuary, located in northern India. Microclimatic variables, such as photosynthetically active radiation （PAR）, air temperature （AT）, soil Lemperature （ST）, ambient atmospheric CO2 concentration, absolute air humidity （AH）, physical and chemical soil ~roperties as well as biological properties were measured. Understory species were assessed via 100 random quadrats （5 m x 5 m） in each of the five forests in which a total of 75 species were recorded encompassing 67 genera from 37 families, consisting of 32 shrubs and 43 plant saplings. DMF was the most dense forest with 34,068 understory individuals per ha of different species, whereas the lowest understory population （13,900 per ha） was observed in the savanna. Ordination and correlation revealed that microclimate factors are most important in their effect compared to ~daphic factors, on the development of understory vegetation in the various forest communities in the north of India.     

Effects of rainwater harvesting on herbage diversity and productivity in degraded Aravalli hills in western India

Over-exploitation and rural growth have severely damaged native vegetations of Aravalli hills in Rajasthan, India. This study was conducted to evaluate the effects of different restoration practices (i.e., rainwater harvesting (RWH) and planting of tree seedlings) on improve- ment in soil water and nutrients and growth and biomass of herbaceous vegetation. Contour trench (CT), Gradonie (G), Box trench (BT), V-ditch (VD) and a control were imposed on 75 plots (each of 700 m 2 ) in natural slope gradient defined as <10%, 10% 20% and >20% slopes in 2005. Each plot had three micro-sites of 1-m 2 at up (USP), middle (MSP) and lower (LSP) part of the plot for observation in 2008. The existed gradient (due to soil texture and topographic features) of soil pH, EC, SOC, NH 4 - N, NO 3 -N and PO 4 -P in June 2005 between >20% to <10% slopes were decreased in 2008 after applying RWH techniques. Such improvement in soil status promoted vegetation growth and biomass in higher slope gra- dients. Soil water, species diversity and herbage biomass increased from USP to LSP, and RWH techniques had positive role in improving SOC, nutrients, vegetation population, evenness and growth at MSP. Despite of lowest SWC, regular rain and greater soil water usage enhanced green and dry herbage biomasses in 10% 20% and >20% slopes, compared with <10% slope. The highest diversity in CT treatment was related to herbage biomass, which was enhanced further by highest concentrations of SOC and PO 4 -P. Further, CT treatment was found to be the best treat- ment in minimizing biomass variance in different slopes. Conclusively, soil texture and topographic features controlled soil water and nutrients availability. Rainwater harvesting techniques increased soil water storage and nutrient retention and also enhanced vegetation status and biomass by minimizing the effects of hillslopes. Thus depending upon the site conditions, suitable RWH technique could be adopted to increase herb- age biomass while rehabilitating the degraded hills.     

Nutrients in litterfall,forest floor and mineral soils in two adjacent forest ecosystems in Greece

The fluxes of masses and the nutrients Ca,Mg,K,N,P and S were determined in the litterfall of two adjacent forest ecosystems of Hungarian oak(Quercus frainetto L.)and European beech(Fagus sylvatica L.)in a mountainous area of northeastern Greece in 2010–2015.The foliar litterfall for both species reached about 70%of the total litterfall,and was significantly higher from the other two fractions(woody and rest litterfall).The fluxes of masses and nutrients were compared between ecosystems for each fraction separately.Only one significant statistical difference was found,that of K in the woody litterfall.In addition,the stocks of masses and nutrients were calculated in the forest floors and mineral soils of the two ecosystems.Likewise,the stocks of nutrients in the forest floors and mineral soils were compared between ecosystems.In the L horizon of the forest floors,statistical differences,as a result of species effect,were found for the stocks of Ca and N.In the FH horizons,the masses and all the nutrient stocks differed significantly,as the beech plot had much higher quantities of organic matter and nutrients.These higher quantities were probably due to low soil temperatures(microclimate)and high acidity in the beech plot(species effect)that slowed down decomposition.In the mineral soils,the propagation of random error derived from random errors of the individual soil layers was an important factor in the statistical comparisons.Because of the soil acidity in the beech plot,the stocks of exchangeable base cations were significantly higher in the oak plot,whereas the other nutrient stocks did not differ.     

Proximate and mineral components of Viscum album var. coloratum grown on eight different host tree species

Mistletoes are parasite plants growing on various tree species,taking nutrients from the host.Beneficial compounds of mistletoe were used in medicine and these mistletoes were commonly collected from oak species that were not well identified.We analyzed the nutritional value by measuring proximate and mineral components of Korean mistletoe(Viscum album var.coloratum)from various host trees.Carbohydrate was the most proximate component in both leaves and twigs followed crude protein,crude fiber,crude ash and crude fat.While the contents of the proximate components and minerals varied among hosts and between plant parts,leaves contained higher crude protein and ash,and more minerals except for magnesium than twigs,although no significant difference was found inmistletoe grown on Prunus mandshurica.There were significant differences of proximate and mineral contents depending on the host species.Mistletoe grown on Chaenomeles sinensis contained higher levels of carbohydrates,crude fat,crude ash,magnesium,calcium,sodium,iron,and zinc than mistletoe grown on other species.Mistletoe grown on P.mandshurica contained high mineral levels of potassium,copper and phosphorous.The nutritional value of mistletoes were greatly influenced by the host species but among the hosts,specific nutrients accumulated in leaves more than in twigs,and vice versa.Based on the analysis,Korean mistletoe contains relatively good quality of nutrients and has high potential for dietary supplements as well as for medicinal compounds.     

Carbon stock measurements of a degraded tropical logged-over secondary forest in Manokwari Regency, West Papua, Indonesia

Several studies have been conducted in the past on carbon stock measurements in the tropical forests of Indonesia.This study is the first related research conducted in the New Guinea Island.In a degraded logged-over secondary forest in Manokwari Regency (West Papua,Indonesia),carbon stocks were measured for seven parts,i.e.,above-ground biomass (AGB),below-ground biomass (BGB),under-storey biomass (B u),necromass of dead leaves (N l),necromass of dead trees (N t),litter (L) and soil (S) using appropriate equations and laboratory analysis.Total carbon stocks were measured at 642.8 tC·ha-1 in the low disturbance area,536.9 tC·ha-1 in the moderate disturbance area and 490.4 tC·ha-1 in the high disturbance area.B u,N l and N t were not significant in the carbon stock and were collectively categorized as a total biomass complex.The carbon stock of litter was nearly equal to that of the total biomass complex,while the total carbon stock in the soil was eight times larger than the total biomass complex or the carbon stock of the litter.We confirmed that the average ratio of AGB and BGB to the total biomass (TB) was about 84.7% and 15.3%,respectively.Improvements were made to the equations in the low disturbance logged-over secondary forest area,applying corrections to the amounts of biomass of sample trees,based on representative commercial trees of category one.TB stocks before and after correction were estimated to be 84.4 and 106.7 tC·ha-1,indicating that these corrections added significant amounts of tree biomass (26.4%) during the sampling procedure.In conclusion,the equations for tree biomass developed in this study,will be useful for evaluating total carbon stocks,especially TB stocks in logged-over secondary forests throughout the Papua region.     

Status of urban vegetation in Guangzhou City

According to a survey for the urban vegetation of Guangzhou, urban vegetation has a significantly difference from natural vegetation because of intense human impacts. The research was conducted in a synthetic survey for soil, species diversity, roadside trees and ecological function of urban vegetation in Guangzhou City. The results showed that: (1) soil densities of urban roadside and park forests were higher than mean density of natural forest soil. The pH values of soil in urban roadside were higher too, and the content of organic matter and the concentration of nitrogen were lower. (2) Species diversity of urban vegetation was lower. The most number of species was only 16 species in tree layers of urban forest. (3) Tree growth was limited by narrow space in high-density urban area, where the trees with defects and disorders were common. (4) Comparing with mature natural forests, the productivity of urban vegetation was lower. The effect of urban vegetation on balance of carbon and oxygen were influenced by the low primary production of urban vegetation. Therefore, the growth condition for urban vegetation should be improved. Biodiversity, primary production and ecological function should be increased for urban vecletation in order to improve urban eco-environment.     

海螺沟主要植被类型

海螺沟属贡嘎山自然保护区的核心区域,原始森林面积超过70 km2.1999年5月至9月及2006年7月,笔者对海螺沟进行了植物多样性调查.基于植被垂直带谱的样带和样方统计,结合相关文献资料,海螺沟有高等植物78科352属1432种（含种下单位）,植被类型的垂直分异表现为不同空间的带状组合,植被类型较为丰富.     

Early recovery process and restoration planning of burned pine forests in central eastern Korea

In central eastern Korea, there has been a continued effort to sustain pine forests because of their value for wood and mushroom production, as well as for other resources. Through the analysis of previously burned areas,we clarified the effects of fire on vegetation dynamics of pine forests by measuring changes in species composition,population structure, and the growth rates of major tree species. Vegetation analysis was conducted on a series of 100 m^2 plots established in Korean red pine(Pinus densiflora Siebold. & Zucc.) and Mongolian oak(Quercus mongolica Fisch. Ex Ledeb.) forests situated in three different topographic positions on slopes where fire severity varied. We confirmed that most pine trees will succumb to even a surface fire, whereas oak may be killed following high intensity or infrequent fires but will sprout and become dominant. Complete protection from fire favors other, more shade-tolerant deciduous hardwoods. Different restoration plans apply, based on observed vegetation responses for each topographic zone. Near the ridge top,where pine seed sources are most limited, it may be necessary to restore pine forests by planting and to control competing shrubs and herbs. At the mountain foot, where exotic species and species modified by hybridization have invaded aggressively, restoration that involves the introduction of natural vegetation is required. Mid-slope sites,where pine has been replaced by natural vegetation dominated by Mongolian oak, do not require any form of restorative treatment.     

不同植被类型蛾类及植物相似性分析

对紫金山不同植被类型植物种类及蛾类群落结构、时空动态进行了调查,运用jaccard相似性分析方法对不同植被类型植物种类、蛾类种的相似性进行了分析,并在植物及蛾类的相似性之间进行了分析探讨。结果表明：紫金山植物种类丰富,植物分布特别是草本植物分布对环境有较强的依赖性。蛾类种亦丰富,有蛾类28科494种,各植被类型植物种类与蛾类种、数量呈正相关,生态环境及植物群落的差异是导致紫金山蛾类群落结构差别的主要因素;紫金山蛾类多食性种较多。紫金山针阔混交林和阔叶林、针阔混交林和针叶林亲缘关系较近,验证了紫金山针阔混交林是由针叶林衰退的基础上自然演替或是人工干预发展而成的,最后将演替成含有常绿成份的落叶阔叶林,各植被类型处于演替的不同阶段,竹林受人为干扰最大。     

淄博市周边破坏山体立地类型划分

以淄博市周边破坏山体为研究对象,根据野外调查结合植被恢复的影响程度,确定了破坏山体外貌形态、边坡高度、坡度、土层厚度和砾石含量5个立地因子,并对之进行了分级量化;利用聚类分析法将破坏山体划分为7个立地类型和16个亚型;不同立地类型特征和植被恢复难易程度不同。     

不同森林植被类型蛾类群落结构及其多样性研究

为揭示不同森林植被类型鳞翅目蛾类昆虫群落的结构状态和功能,评价不同植物群落的生态稳定性,于2007～2008年对紫金山主要植被类型蛾类昆虫种类、种群密度、分布及发生规律进行了调查;对不同植被类型、不同季节、整体时间动态的蛾类昆虫进行了多样性方面的分析研究.结果表明:紫金山共有蛾类13总科28科355属494种,阔叶林蛾...     

广元3种林分类型生物产量与磷素空间格局的研究

本文以川北低山暴雨区水土流失定位观测站内的3个不同植被恢复模式为研究对象,通过野外调查与室内实验相结合的方法,对湿地松纯林,刺槐纯林及湿地松刺槐混交林生态系统内生物量及各器官磷素分配格局进行了分析,研究表明:1、3种不同植被类型林分生物量大小顺序为湿地松纯林>混交林>刺槐纯林,在生物量组成上,均为乔木层生物量大于灌木层及层间植物的生物量;2混交林中湿地松和刺槐的树叶、树皮及刺槐果的磷素含量分别大于纯林中的对应器官的磷素含量,湿地松纯林和混交林中枝的磷素含量分别是0.261 g.kg-1和0.264 g.kg-1,而刺槐树枝的磷素含量在纯林和混交林中分别为0.454 g.kg-1和0.348 g.kg-1;混交林中林分总磷素含量大于湿地松林分磷素含量而小于刺槐林分磷素含量,其乔木层和灌木层中的磷素含量的大小顺序与林分磷素总含量一致。     

广西不同植被类型地表径流的研究

1982—1989年,采用定位对比对不同植被类型的地表径流量及动态进行了观测研究。结果表明:1.不同植被类型的地表径流差异很大,草坡>针叶林>阔叶林或针阔混交林;区内各植被类型的径流系数较小,平均为0.78％,但各类型间差异很大,可达57倍强。2.地表径流的季节动态,主要受降水的季节分配规律制约;而不同植被类型的地表径流量主要受植被的树冠群体或植物群体、枯枝落叶层和土壤层的综合效能所决定。这种综合效能呈现阔叶混交林或针阔混交林大于针叶林、针叶林大于草坡地的规律。文中还建立了不同植被类型地表径流深与林外降雨量的回归模型。     

Spatial pattern of soil carbon and nutrient storage at the alpine tundra ecosystem of Changbai Mountain,China

气候变化对土壤碳和养分的影响越来越受到生态学家的关注,尤其是对高山冻原生态系统的影响。本研究目的是长白山高山冻原系统土壤碳和养分的空间异质性。结果表明:不同土层深度的土壤碳在Meadow alpine tundra vegetation (MA)中显著地高于其他植被类型(p<0.05);在每一植被类型中,表层(010 cm)碳含量显著地高于1020 cm的土层;土壤氮的分布格局是氮素在表层和1020 cm土层变化规律相似;不同土层深度的土壤磷在Lithic alpine tundra vegetation (LA) 中显著地低于其他植被类型(p<0.05);土壤钾浓度在Felsenmeer alpine tundra vegetation (FA) 和LA中显著地高于其他植被类型,但在每一植被类型中土壤钾浓度随土壤深度没有明显的变化;不同深度土壤硫在MA中显著地高度其他植被类型;对每一植被类型而言,C: N, C: P, C: K 和C: S随土壤深度增加而降低。除了在SA的表层外,表层的土壤C: N高于1020 cm的土层。在长白山高山冻原系统中,随植被类型的变化,土壤碳和养分储量有着显著的空间异质性。参29表3图1。     

坝上高寒区城市园林植物应用现状与分析

以河北省坝上地区的张北、尚义、沽源、康保四县城市园林为研究对象，通过分区样方调查、市民意愿访问及对比国家标准等方式，分析了区域园林植物应用种类、结构配置、层次和季相分布，以及非绿期植被等景观生态效果。结果表明，坝上城市园林植物应用种类少，受偏好造林及疏于管护影响，以旱柳、垂榆、白榆、小叶杨等乡土树种为主的乔木类应用普遍，花灌木和地被植物配植比例偏低，形成以乔木为主的寡层片园林景现。坝上道路、企事业单位的绿化效果接近国家最低标准，居民区显著低于国家标准。区域绿期植被简单、花季短促，非绿期植被覆盖度大幅下降，直接影响了固土减尘、保护环境的生态效果。基于高寒干旱生境特征，区域多年生地被植物的引用成为丰富园林景观结构、展宽花季、提高冬春季节地面覆盖度的关键。