Herb Diversity Research Articles

Tree Cover Improved the Species Diversity of Understory Spontaneous Herbs in a Small City

A large number of trees have been planted in built-up areas to improve the urban environment, but the effects of tree cover on spontaneous understory herbs are not yet well understood. This study surveyed spontaneous herbs in two kinds of habitats (habitats with and without tree cover) in the built-up area of the small city Junlian in Sichuan Province, China. A total of 222 species of spontaneous herbaceous plants in 180 genera of 71 families were recorded, including a vulnerable species and six species endemic to China. Although the overall species richness values were similar in the two kinds of habitat, the average species richness per quadrat of all plants, perennials, plants with the dwarf growth form, and animal-dispersed plants was significantly higher in the habitats with tree cover than in those without tree cover. The overall species association was significantly positive in the habitats with tree cover (VR = 1.51, p < 0.05) and neural (VR = 0.86) in the habitats without tree cover. Among the top 25 frequently recorded species in each kind of habitat, the species association of plants with the same trait combination type differed greatly in the two kinds of habitats. For the species association between annuals, only 13.33% of species pairs were significantly associated in the habitats with tree cover, while 22.22% of the species pairs were significantly negatively associated in the habitats without tree cover. For the species association between plants with tall growth forms, the proportion of significant positive associations in the habitats with tree cover was approximately twice than in the habitats without tree cover. For the species association between plants with the dwarf growth form, the proportion of negative associations in the habitats without tree cover was approximately twice that in the habitats with tree cover. Species with the same dispersal mode generally had a very low proportion of negative interspecific associations or a high proportion of positive interspecific associations in habitats unfavorable to their establishment. Our findings suggest that tree cover can improve the species richness of the spontaneous herbaceous species beneath them and profoundly influence interspecific coexistence relationships in a built-up area.

The effects of natural enemies on herb diversity in a temperate forest depend on species traits and neighbouring tree composition

Abstract There is mounting evidence that top‐down control by natural enemies helps maintain plant diversity in natural ecosystems. Previous work has concentrated on either forest trees or grassland herbs. Our knowledge of how natural enemies affect herb diversity in forests is limited. We used fungicides and insecticide to experimentally examine the effects of fungi and insects on herb abundance and diversity at the community‐wide scale and within groups of species with certain traits. We also assessed how the effects of fungi and insects on herb assemblages were modified by neighbouring tree diversity and composition in an old‐growth temperate forest. We found that fungicides increased overall herb abundance by 7% while decreasing herb diversity by 5%. This effect of fungicides on both herb abundance and diversity weakened with the increase of neighbouring tree diversity. Insecticide did not affect either herb abundance or diversity noticeably, except in areas dominated by deciduous trees where insecticide application reduced herb diversity. Fungicides and insecticide decreased the diversity of relatively less defended species (i.e. thin‐leaved and non‐clonal) but had no effect on the diversity of herbs with stronger defensive traits (i.e. thick‐leaved and clonal). Fungicides increased the abundance of non‐mycorrhizal (NM) species but not arbuscular‐mycorrhizal (AM) species, although the effect of fungicides on herb diversity was unrelated to species' mycorrhizal association. Insecticide had stronger effects on the abundance and diversity of NM species than AM species. Synthesis. We conclude that fungi and insect herbivores are critical to regulating herb abundance and diversity in this temperate forest, with their effects dependent on species' traits and neighbouring tree diversity and composition. Our results highlight the importance of top‐down control of understory herb communities by natural enemies in temperate forests, advancing our understanding of the processes shaping plant diversity in natural ecosystems.

Thinning can increase shrub diversity and decrease herb diversity by regulating light and soil environments.

Tree thinning affects the light environment, which in turn affects the growth and survival of understory vegetation, thus improving species diversity and nutrient cycling, as well as the ecological habitat factors. However, the response of understory vegetation to the thinning intensity and short-time effects in the temperate broadleaf-conifer mixed forest is not completely clear. In this study, four permanent plots with a total area of 4 hm2 were established in a mixed broadleaf-conifer forest in northeast China, with thinning intensities of 20% (light thinning, LT), 35% (medium thinning, MT), 55% (heavy thinning, HT) and the unthinned plot (CK), respectively, in accordance with the basal area. The responses of species diversity to changes in understory vegetation were conducted by a structural equation model (SEM). The results showed that compared with CK, thinning significantly increased the photosynthetically active radiation (PAR) and the light quality (R/FR) (p < 0.05), while decreased the contents of soil total nitrogen (TN), total phosphorous (TP), organic matter (OM), nitrate nitrogen (NN), ammonia nitrogen (AN) and pH. The degree of fragmentation of light factors among the treatment plots gradually decreased as thinning intensity increased. Among all the thinning treatments, PAR and R/FR were found to be the optimal light condition when the forest thinning intensity was 55%. The light condition was found to have a significant negative correlation with soil TN, TP, OM, and AN. While the soil nutrients were positively correlated with herbaceous layer diversity but negatively correlated with shrub layer diversity. The soil nutrients were lost after thinning in a short time and herb diversity decreased, but shrub diversity increased significantly compared with unthinned plots. For the understory vegetation, the species diversity of shrub and herb layer were showed to be more sensitive to soil nutrients than light environment.

Diversity of herbs and spices plants and their importance in traditional medicine in the South Aceh District, Indonesia

Abstract. Adnan, Navia ZI, Silvia M, Antika M, Suwardi AB, Baihaqi, Yakob M. 2022. Diversity of herbs and spices plants and their importance in traditional medicine in the South Aceh District, Indonesia. Biodiversitas 23: 3836-3843. Kluet people are one of the ethnic communities living in Southern Aceh, Indonesia. Various herbs and spices plants are used by the Kluet people as a traditional medicine in treating diseases and disorders. The study aimed to investigate the diversity of herbs and spices plants and their importance in the traditional medical system. It was based on field surveys, plant collection, and semi-structured interviews with the local people. Interviews were performed with 355 informants selected by using the random sampling technique. A total of 30 medicinal plant species, consisting of 18 families, have been documented. Curcuma longa, Kaempferia galanga, Zingiber officinale, Citrus x aurantiifolia, Alpinia galanga, Averrhoa bilimbi, Elettaria cardamomum, Allium sativum, Cocos nucifera, and Syzygium aromaticum are the most popular medicinal plants known by Kluet people. More than 40% of traditional knowledge related to the use of herbs and spices as traditional medicine was obtained from their families/friends/neighbors. Traditional knowledge is thought to decline among generations. It is supposedly due to lifestyle changes as a result of modernization. The documentation and promotion of traditional medicine systems through formal and non-formal education may contribute to the conservation of biodiversity and traditional knowledge.

Impact of forest fire frequency on floristic diversity in the forests of Uttarakhand, western Himalaya

The Uttarakhand State of India is rich in forest wealth with 45.4% forest cover (India State of Forest Report (2021). However, forest cover may change due to a number of anthropogenic and environmental factors. One of the factors leading to forest degradation is forest fires. Forest fires are related to factors that may be biotic, such as heavy accumulation of Chir pine (Pinus roxburghii, a dominant forest forming tree) needles on the forest floor influencing fuel load accumulation and flammability, or abiotic, such as climate, topography, or soil type influencing fuel moisture and fire spread. This study was carried out using satellite images of study area where fire was classified using the geographical information system (GIS) into four frequency classes (no fire, low fire, moderate fire, and high fire). We sampled a total of 160 quadrates for trees, 320 for shrubs and 480 for herbaceous plants to assess vegetation diversity for each forest fire frequency class. No fire was recorded for 13,619 sample points, which covers an area of 84% of the study area, whereas low fire frequency was recorded for 1784 sample points covering an area of 11%. In the present study, significant differences in species diversity were observed across the fire frequency classes. While species diversity increased in the low fire frequency class, an increase in fire frequency led to a decline in diversity and increased dominance of certain fire-tolerant species. Our results show that species richness and density decreased in higher fire frequency classes, which could be due to a poor regeneration process. We found that tree species diversity was higher for the low fire frequency class, followed by moderate fire frequency class, no fire frequency class, and was lowest for the high fire frequency class. The diversity of herbs decreased with increasing fire frequency, from a minimum of 12 species in the high fire frequency class to a maximum of 37 in the no fire frequency class. Some of the fire-adapted species were Myrica esculenta, Pyrus pashia, Lyonia ovalifolia, Carissa spinarum, Pyracantha crenulata, Desmodium microphyllum, and Micromeria biflora the regeneration of which should be promoted rehabilitate the fire damage forest ecosystem of Uttarakhand.

A Comparative Study of Genetic Responses to Short- and Long-Term Habitat Fragmentation in a Distylous Herb Hedyotis chyrsotricha (Rubiaceae).

The genetic effects of habitat fragmentation are complex and are influenced by both species traits and landscape features. For plants with strong seed or pollen dispersal capabilities, the question of whether the genetic erosion of an isolated population becomes stronger or is counterbalanced by sufficient gene flow across landscapes as the timescales of fragmentation increase has been less studied. In this study, we compared the population structure and genetic diversity of a distylous herb, Hedyotis chyrsotricha (Rubiaceae), in two contrasting island systems of southeast China. Based on RAD-Seq data, our results showed that populations from the artificially created Thousand-Island Lake (TIL) harbored significantly higher levels of genetic diversity than those from the Holocene-dated Zhoushan Archipelago (ZA) (π = 0.247 vs. 0.208, HO = 0.307 vs. 0.256, HE = 0.228 vs. 0.190), while genetic differences between island and mainland populations were significant in neither the TIL region nor the ZA region. A certain level of population substructure was found in TIL populations, and the level of gene flow among TIL populations was also lower than in ZA populations (m = 0.019 vs. 0.027). Overall, our comparative study revealed that genetic erosion has not become much stronger for the island populations of either the TIL or ZA regions. Our results emphasized that the matrix of water in the island system may facilitate the seed (fruit) dispersal of H. chrysotricha, thus maintaining population connectivity and providing ongoing resilience to the effects of habitat fragmentation over thousands of years.

Response of understorey vegetation in chir pine forests to prescribed burning in Shiwalik region of Himalaya

Aim: The present investigation was carried out to understand the impact of controlled/prescribed burning on understorey vegetation in chir pine (Pinus roxburghii) forests of Shiwalik region to manage the summer fire damage. Methodology: Chir pine forest areas of two hectares (ha) each were selected at three sites in Shiwalik region of Himalaya for prescribed burning. Each forest area was delineated into three plots of which one plot was burnt during mid-winter in the year 2017 (B1) and another plot burnt twice (B2) during 2017 and 2018 whereas the third was kept unburnt plot (C) in each site. The phytosociological attributes of understorey vegetation were studied in November, 2018. The difference in density of shrubs (plants 25 m-2) and herbs (plants m-2) in unburnt (C), once burnt (B1) and twice burnt (B2) was analyzed through critical difference (CD). Results: Total density (plants 25m-2) of shrubs ranged from 7.15 to 12.95 in unburnt (C), 3.90 to 8.40 in once burnt (B1) and 2.25 to 4.65 in twice burnt (B2) plots whereas total density (plants m-2) of herbs varied from 25.83 to 44.95 in unburnt (C), 33.20 to 75.92 in once burnt (B1) and 29.31 to 90.93 in twice burnt (B2) plots. The density of shrubs was significantly higher in unburnt plots (C) as compared to burnt plots and vice versa for herbs. The Shanonn Wiener Index (H) ranged from 1.76 to 2.39 for shrubs and 2.32 to 3.15 for herbs. Interpretation: The density of herbs was higher in burnt plots and it was vice versa for shrubs. The prescribed burning enhanced diversity of herbs while shrubs diversity decreased with burning.

Coupled Relationship between Soil Physicochemical Properties and Plant Diversity in the Process of Vegetation Restoration

An in-depth exploration of plant–soil interactions can improve our knowledge of the succession and evolution of forest ecosystems. To understand the coupling relationship between species diversity and soil physicochemical properties in natural secondary forests during the process of vegetation restoration, the species diversity of trees, shrubs and herbs and the physicochemical properties of soil at different depths were investigated in six forest communities in the Qinling Huoditang area over two years (2013 and 2019). The analysis indicated that the soil nutrient content in the region decreased during this period, but the plant diversity index showed no obvious change. Through RDA and regression analysis, we determined that the correlations between plant diversity and soil physicochemical properties were discrete. The tree and herb species diversity were most closely related to the surface soil, while shrub diversity was more strongly regulated by the middle soil layer. Available phosphorus had the strongest effect on trees, and the main factors affecting shrubs were NO3-N and NH4-N. Herb growth was more limited by soil physical properties such as the soil bulk density and porosity. We concluded that evident correlations exist between soil physicochemical properties and plant communities. After six years of natural restoration, the plant diversity index did not change significantly. However, the soil nutrient content decreased obviously. This study provides a reference for the management of vegetation restoration processes in forest ecosystems.

Assessing the Impact of Road and Land Use on Species Diversity of Trees, Shrubs, Herbs and Grasses in the Mountain Landscape in Southern Africa

Mountain landscape, described as a global biodiversity hotspot due to high endemism, is threatened by land-use change, including management and modification of vegetation. However, there is little knowledge about how road and land use affect plant diversity in mountains landscapes, particularly in southern Africa. Previous studies have studied the impact of the road or land use on plant species diversity separately and have concentrated on a single plant species. Here we compare the plant diversity of regenerated trees, shrubs, herbaceous plant, and grasses among Forest, Fallow, Agriculture, and Road in the Moribane Forest Reserve (MFR), in Eastern Chimanimani Mountain landscape in Mozambique. To assess how land-use change affects plant diversity, we conducted 45 transects along the roadside and randomly established 24 quadrats in the Agriculture fields and Fallow and 26 quadrats in the pristine Forest. In each transect and quadrats, we recorded the occurrence of four plant life forms (regenerated trees, shrubs, herbaceous, and grass species) to determine the alpha and beta-diversity across land-uses, and we assessed the invasiveness of each species. Species composition varied significantly among the land-uses types. Roadside had higher species diversity and the highest number of invasive species (138 total species of all plant life forms; 31 invasive species), following Agriculture (72; 30), Fallow (81; 20), and Forest (78; 19). There was no similarity in species between roadsides and other land-uses. Furthermore, roadside recorded the highest average species turnover for all plant life forms following Agriculture, Forest, and Fallow. Among the plants, the most important life form was herbaceous with 143 species, following grass with 86 species, shrubs with 86, and regenerated trees with 65 species. The land-use pattern makes the landscape more diversified in the study area and, as a result, increase the plant species richness and diversity by species replacement. This study is unique in collecting and analyzing data on different plant life forms on roadsides linked with a range of different land-use types within a small region of a mountain landscape in southern Africa.

Responses of Fine Roots at Different Soil Depths to Different Thinning Intensities in a Secondary Forest in the Qinling Mountains, China.

Simple SummaryFine roots of different sizes make critical contributions to carbon stocks and terrestrial productivity, but the changed characteristics of fine roots with different diameters at different soil depths under thinning disturbances remain poorly understood. In our study, we aimed to elucidate the response characteristics of fine roots with different diameters to thinning intensities at different soil depths, and to explore the driving mechanism of the change in the fine-root characteristics. We found that higher thinning intensities negatively affected 0.5–1 mm and 1–2 mm fine-root biomass, while the <0.5 mm fine-root characteristics fluctuated with increasing thinning intensities. Our results suggest that the thinning intensity exhibits varied influential mechanisms on the changed characteristics of <0.5 mm fine roots and thicker fine roots (0.5–2 mm). Collectively, our findings provide important insights into the effects of forest management on changes in fine-root characteristics, and supplement meaningful data on fine-root productivity to improve the parameterization of future ecological models.Fine roots make critical contributions to carbon stocks and terrestrial productivity, and fine roots with different diameters exhibit functional heterogeneity. However, the changed characteristics of fine roots with different diameters at different soil depths following thinning disturbances are poorly understood. We investigated the biomass, production, mortality and turnover rate of <0.5 mm, 0.5–1 mm, and 1–2 mm fine roots at 0–20 cm, 20–40 cm, and 40–60 cm soil depths under five thinning intensities (0%, 15%, 30%, 45%, and 60%) in a secondary forest in the Qinling Mountains. The biomass, production and turnover rate of <0.5 mm fine roots fluctuated with increasing thinning intensities, while the 0.5–1 mm and 1–2 mm fine-root biomass significantly decreased. The thinning intensities had no effects on the fine-root necromass or mortality. The change in the fine-root characteristics in deeper soils was more sensitive to the thinning intensities. The principal component analysis results showed that increased <0.5 mm fine-root biomass and production resulted from increased shrub and herb diversity and biomass and decreased soil nutrient availability, stand volume, and litter biomass, whereas the 0.5–1 mm and 1–2 mm fine-root biomass showed the opposite trends and changes. Our results suggest that different thinning intensities exhibit varied influential mechanisms on the changed characteristics of fine roots with different diameters.

Large mammalian herbivores modulate plant growth form diversity in a tropical rainforest

Abstract The world’s terrestrial biomes are broadly classified according to the dominant plant growth forms that define ecosystem structure and processes. Although the abundance and distribution of different plant growth forms can be strongly determined by factors such as climate and soil composition, large mammalian herbivores have a strong impact on plant communities, thus defaunation (the local or functional extinction of large animals) has the potential to alter the compositional structure of plant growth forms in natural ecosystems. Tropical rainforests sustain a high diversity of growth forms, including trees, palms, lianas, shrubs, herbs and bamboos, all of which play important ecosystem functions. Here, we experimentally evaluate how large mammalian herbivores affect the dominance, diversity and coexistence of these major tropical forest plant growth forms, by monitoring communities of saplings on the understorey in 43 paired exclusion plots in a long‐term replicated exclusion experiment in the understorey of the Atlantic forest of Brazil. Over the course of 10 years large herbivore exclusion decreased diversity among growth forms, increased the absolute abundance of palms and trees (22% and 38% respectively) and increased the diversity of species within these two groups, to the detriment of other growth forms. Furthermore, all pairwise relationships between growth forms were positive on plots where herbivores had access, whereas several strong negative relationships emerged in plots where herbivores were excluded. This occurred despite strong background directional temporal trends affecting plant communities in both experimental treatments across the region. Synthesis. Our work indicates that the defaunation alters growth form dominance by favouring palms and trees while eroding diversity among growth forms and coexistence on a temporal scale. Large herbivore mammals promote diversity among growth forms, preventing the hyper‐dominance of trees and palms, yet without supressing the diversity of species within growth forms. We argue that large herbivore mammals affect growth forms through several non‐mutually exclusive mechanisms, including herbivory, seed dispersal and physical disturbance, as well as differential effects linked to the morphological and physiological adaptations of growth forms. We conclude that defaunation might lead to profound impacts on important ecosystem functions underpinned by growth form diversity, and result in vertical and horizontal structural simplification of tropical rainforests.

Coprolite palynology from Abrigo do Lagar Velho (Portugal) and a revision of Gravettian vegetation in the Iberian Peninsula

Palynological investigations on Gravettian coprolites of Abrigo do Lagar Velho (Vale do Lapedo, Leiria, Portugal) dated between ca. 30 to ca. 27.3 ka cal BP are presented. The palaeoecological data shows a semi-forested landscape with Pinus, Poaceae, Erica, Artemisia, Juniperus and Quercus as the dominant taxa. A diversity of trees, shrubs, and herbs is also noticeable, including broad-leaf trees, Mediterranean woody shrubs and trees, conifers, xerothermophytes, indicators of saline substrates and heliophytes such as Erica, Asteroideae, Cistaceae, Ephedra fragilis and E. distachya. The overall reconstruction is a mosaic of different landscapes or types of vegetation around the rock-shelter. Indeed, we provided approach on the Gravettian vegetation of the Iberian Peninsula, connecting the palaeoecosystem with the biogeography of past human populations during the late Pleistocene.

Divergent herb communities in drier and chronically disturbed areas of the Brazilian Caatinga

Although the herbaceous plants concentrate the diversity of vascular plants in the largest dry forest of South America, the Brazilian Caatinga, their responses to environmental modifications are poorly known. We assessed the taxonomic, phylogenetic and functional responses of herb communities to independent gradients of annual rainfall (510−940 mm), chronic disturbance (0–100%), and local density of woody plants in 19 forest sites of the Catimbau National Park, Northeast Brazil. We expected that drier and more chronically disturbed stands with greater density of woody plants would support less-dense and impoverished herb communities. We recorded 6787 individuals belonging to 57 species and 53 genera, predominantly dicots. Rainfall reduction decreased herb density, benefited a small set of particular genera, increased phylogenetic clustering within terminal clades and favored species pollinated by birds and butterflies. Increased chronic disturbance did not affect herb density and richness, but benefited another set of herb genera, reduced phylogenetic clustering and favored dicot herbs pollinated by bees. The density of woody plants also affected different aspects of taxonomic, phylogenetic and functional dimensions. By shaping different components of herb diversity, rainfall reduction and increased chronic disturbance are likely to act synergistically and drive the Caatinga towards multiple successional pathways.

Tipping the scales: how fire controls the balance among functional groups in Angolan grasslands

Fire plays an important role in the ecology of tropical grasslands globally. However, detailed studies comparing the response of plant functional groups to fire seasonality, and thus phenological timing, are scarce from humid Afrotropical grasslands. Such information, however, is crucial for understanding what keeps the grasslands open and for enabling evidence-based management, and conservation. We initiated an experiment in frost- and fire-prone Angolan geoxyle grasslands in 2017, investigating the effect of different timing of fires on cover and diversity of trees, grasses, geoxyles and herbs. We installed permanent, randomised plots with fire exclusion, annual early and late dry-season burning, representing the local burning practices. Functional plant groups reacted differently to the treatments, becoming apparent at species level and their performance metrics. After three years, grass species benefitted from late and no burning, and herbs from late burning, whereas geoxyles thrived under early burning. Tree growth was suppressed under late burning, and did not increase with fire exclusion. Species richness and diversity was higher in burnt than in unburnt plots. Seasonal timing of fire tips the scales between geoxyles and grasses. The extraordinary plant diversity of Angolan geoxyle grasslands is a result of pyrodiversity and frost, keeping the grasslands open even in absence of fire.

氮添加对红松人工林草本层植物多样性的影响

PDF HTML阅读 XML下载 导出引用 引用提醒 氮添加对红松人工林草本层植物多样性的影响 DOI: 10.5846/stxb202110122873 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家科技基础资源调查专项（2019FY202300） Effects of nitrogen addition on species diversity of the understory plants in the Korean pine plantation Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:氮沉降是驱动生物多样性变化的重要因素之一。为了探索氮添加对红松（Pinus koraiensis）人工林草本层植物多样性的影响及其驱动机制，以黑龙江凉水国家级自然保护区红松人工林为研究对象，设置N0（对照处理，0 kg hm-2 a-1）、N20（低氮处理，20 kg hm-2 a-1）、N40（中氮处理，40 kg hm-2 a-1）和N80（高氮处理，80 kg hm-2 a-1）4个施氮水平，进行6年的氮添加实验。结果表明：（1）氮添加显著降低草本层3个功能群的密度和盖度，而对高度无显著影响；（2）6年氮添加使对照与施氮处理间群落相似度随施氮水平的增加而减小；（3）氮添加显著降低草本植物的丰富度和Shannon-Wiener多样性指数，而未对蕨类和木本植物的丰富度和Shannon-Wiener多样性指数产生显著影响，对草本层3个功能群的Pielou均匀度指数均无显著影响；（4）氮添加对草本植物的C、N、P含量、N：P、C：P产生显著影响，对木本植物的P含量、N：P、C：P产生显著影响，对蕨类植物的C：N：P生态化学计量均无显著影响；（5）草本植物多样性与土壤化学性质无显著的相关关系，草本植物丰富度、Shannon-Wiener多样性指数与植物盖度、密度呈显著的正相关关系，丰富度与植物N含量呈显著的负相关关系，Shannon-Wiener多样性指数与植物N：P呈显著的负相关关系。研究表明6年氮添加改变植物草本层中物种组成和群落结构，3个功能群密度和盖度显著降低，高度未产生显著变化，仅降低草本植物的丰富度和多样性。造成该现象的原因可能是，不同物种对于氮的利用特性和耐受程度存在差异，氮添加引起草本植物养分失衡，改变物种组成和群落结构，从而影响草本植物多样性。研究结果可为我国温带森林生态系统持续性管理提供数据和理论基础。 Abstract:Nitrogen deposition is one of the important driving factors of biodiversity change. To explore the effect of nitrogen addition on the understory plants diversity of the Korean pine (Pinus koraiensis) plantation and its driving mechanism, we simulated N deposition with four levels of N addition rate N0 (control treatment, 0 kg hm-2 a-1), N20 (low nitrogen treatment, 20 kg hm-2 a-1), N40 (medium nitrogen treatment, 40 kg hm-2 a-1) and N80 (high nitrogen treatment, 80 kg hm-2 a-1) for 6 years, based on the Korean pine plantation in Liangshui National Nature Reserve in Heilongjiang Province. The results showed that:(1) nitrogen addition significantly reduced the density and coverage of the three functional groups in the understory plants, but had no significant effect on the height. (2) The 6-year nitrogen addition reduced community similarity between control and nitrogen application treatment decreased with the increase of nitrogen application level. (3) Nitrogen addition significantly reduced the Shannon-Wiener diversity index and species richness of herbs in the Korean pine plantation. Nitrogen addition had no significant effect on the species richness and Shannon-Wiener diversity index of woody plants and ferns. Nitrogen addition had no significant effect on the Pielou evenness index of the three functional groups of herbs. (4) Nitrogen addition had significant effects on the contents of C, N, P, N:P and C:P of herbs. Nitrogen addition had significant effect on the contents of P, N:P and C:P of woody plants, and it had no significant effect on C:N:P ecological stoichiometry of ferns. (5) There was no significant correlation between herb diversity and soil chemical properties. There was significantly positive correlation between species richness of herbs, Shannon Wiener index and coverage, density of herbs. There was significantly negative correlation between species richness of herbs and plant N content, and between herb Shannon Wiener index and plant N:P. The 6-year nitrogen addition changed the species composition and community structure in the understory plants, significantly reduced the density and coverage of the three functional groups, and had no significant change on the height, and it only reduced the species richness and Shannon-Wiener diversity index of herbs. The reason for this phenomenon may be that different species have different nitrogen utilization characteristics and tolerance, and nitrogen addition causes nutrient imbalance of herbs, changes species composition and community structure, and affects herbs diversity. The results provide data and theoretical basis for the sustainable management in temperate forest ecosystems in China. 参考文献 相似文献 引证文献

Aloin Content Determination In Aloe Vera With Its Physicochemical Properties Along With Its Physicochemical And Phytochemical Evaluation In Piper nigrum

Abstract-India has a vast diversity of herbs. Around 3,000 years before, these herbs were acknowledged and use as medicinal plants and helpful for treating people. New scientific research has established that some plants and herbs have presence of many active compounds and possess specific pharmacological properties. Aloe vera (ghritkumari) and Piper nigrum (black pepper or maricha) are the oldest plants which are used as a medicinal herb as well as in household. Aloe vera or Ghritkumari species are currently used by cosmetic and pharmaceutical industries. Aloe vera has antibacterial, antiviral, and antiseptic properties which help to treat skin-related problems. Piper nigrum is a species that is used in various medications since very old times. They have also been used as domestic medicine against various infections, a quality attributable to the existence of certain chemical moieties in them. Physicochemical analysis and bioactive compound evaluation of the medicinal plants in essence ofAloe veraandPiper nigrum was undertaken in this study.In physicochemical analysis of aloe vera, many parameters were tested against pulp extract and leave extract (i.e., pulp and leave); parameters are color, odour, taste, total solid, total ash value, total dissolved solid, specific gravity, PH, refractive index. For aloin content evaluation, High-Performance Layer Chromatography techniques were used in the Aloe vera plant. In physicochemical analysis, many standardization parameters like alcohol soluble extractive values, water-soluble extractive values, loss on drying, total ash value, acid insoluble ash and total ash value of P. nigrum fruits were analysed. For phytochemical screening, following a 6-stage extraction process is performed, the extracts collected fromP.nigrum were exposed to a number of preliminary biochemical and phytochemical tests. The presence of tannins, saponins, terpenoids, flavonoids, and alkaloids wastested in the chloroform and aqueous extract which is used in the following investigation. However, from the aggregation of all our results, we concluded that the presence of these phytochemicals and bioactive component in these medicinal plants indicates potential therapeutic properties for welfare of humans.

Vegetation Structure and Carbon Stock of Two Community Managed Shorea robusta Forests of Dhangadhi, Nepal

Community forests play a vital role in sustainable development and storing carbon stock to mitigate global warming. This study aimed to assess the plant diversity, carbon stock and regeneration status of two Shorea robusta forests managed by the community - Manehara Community Forest (MCF) and Siddhanath community forests (SCF) of Kailali district, Nepal. These two forests differ in the moisture regime- MCF is with ponds and streams and is mostly wet, but SCF is primarily dry with no ponds and streams. To examine vegetation status and carbon stock in these two forests, twenty circular plots of 20 m radius was laid in each forest using stratified random sampling. Within each main plot, two subplots of 5m radius and three subplots of 2m radius were laid to study shrub and herb characteristics, respectively. Soil sampling was also done to analyze the role of soil moisture in carbon stock and regeneration. For this, soil samples of each plot were collected up to 20cm depth. Altogether 100 plant species were recorded from the study forests. Tree and shrub diversity was higher in MCF than in SCF, but herb diversity and seedling numbers were higher in relatively dry SCF than in MCF. The carbon stock of MCF (92.99t/ha) was higher than in SCF (51.94 t/ha). In both forests, carbon stock increased with the increasing basal area (P = 0.0001). A significant strong positive relationship (P = 0.0001) between density and carbon stock was found in SCF, but this relation was weak (P = 0.018) in MCF. Both community forests were fairly regenerating with a good number of small aged individuals, SCF shows an inverted J shaped density diameter (d-d) curve, whereas MCF shows a bell-shaped d-d curve.

Characteristics and factors influencing the natural regeneration of Larix principis-rupprechtii seedlings in northern China.

Larix principis-rupprechtii is an important and widely distributed species in the mountains of northern China. However, it has inefficient natural regeneration in many stands and difficulty recruiting seedlings and saplings. In this study, we selected six plots with improved naturally-regenerated L. principis-rupprechtii seedlings. A point pattern analysis (pair-correlation function) was applied to identify the spatial distribution pattern and correlation between adult trees and regenerated seedlings mapped through X/Y coordinates. Several possible influencing factors of L. principis-rupprechtii seedlings’ natural regeneration were also investigated. The results showed that the spatial distribution patterns of Larix principis-rupprechtii seedlings were concentrated 0–5 m around adult trees when considering the main univariate distribution type of regeneration. There was a positive correlation at a scale of 1.5–4 m between seedlings and adult trees according to bivariate analyses. When the scale was increased, these relationships were no longer significant. Generally, adult trees raised regenerated L. principis-rupprechtii seedlings at a scale of 1.5–4 m. Principal component analysis showed that the understory herb diversity and litter layer had a negative correlation with the number of regenerated seedlings. There was also a weak relationship between regenerated numbers and canopy density. This study demonstrated that the main factors promoting natural regeneration were litter thickness, herb diversity, and the distance between adult trees and regenerated seedlings. Additionally, these findings will provide a basis for the late-stage and practical management of natural regeneration in northern China’s mountain ranges.

Self-management using crude herbs and the health-related quality of life among adult patients with hypertension living in a suburban setting of Malaysia.

PurposeTo determine the prevalence of crude herbs’ use in the self-management of hypertension and the health-related quality of life (HRQOL) in patients with hypertension.MethodsThis cross-sectional study was performed among patients with hypertension attending a government health clinic. Socio-demographic characteristics, lifestyle modifications, medical history and predictors of crude herbs users were obtained. The diversity of crude herbs used was assessed using a modified international complementary and alternative medicine questionnaire (I-CAM-Q) and the HRQOL was assessed using the SF36 instrument.ResultsOut of the 294 patients recruited, 52.4% were female, 41.5% were Malay and 38.8% were within the 60 to69 age category. The prevalence of crude herbs users was 30.6% and the most common herbs used were pegaga (Centella asiatica), peria (Momordica charantia) and betik (Carica papaya). Using the regression analysis, significantly higher odds of using crude herbs are noted among Malay or Indian patients who have these characteristics: attained secondary education, experienced falls or muscle pain, and had systolic blood pressure of more than 140 mmHg. There was no significant difference in HRQOL domains between the crude herb users and non-users (p>0.05).ConclusionBesides taking allopathic medications, certain patients with hypertension use crude herbs as a form of self-management. Although patients are adamant about integrating crude herbs as a form of self-management, the effects of doing so have not been properly investigated. This implies that the healthcare staff members need to communicate with the patients regarding the use of crude herbs together with conventional drugs.

Research on Species Diversity of Pinus radiata Plantation under Different Afforestation Models in Dry-hot Valley of the Minjiang River

According to the field experiment, the species diversity of Pinus radiata pure forest, Pinus radiata and Cupressus chengiana mixed forest, Pinus radiata, Cupressus chengiana and Robinia pseudoacacia mixed forest was studied in Wenchuan, Lixian and Maoxian dry-hot valleys of the Minjiang River. The results showed that: (1) Ailanthus altissima was the common accompanying tree species in the tree layer of P. radiata plantation, Lespedeza bicolor was the dominant species in the shrub layer, and Artemisia had great regeneration potential in the herb layer. The species richness was in the order of herb layer > shrub layer > tree layer, and Asteraceae, Gramineae and Leguminosae were the dominant species under the forest. (2) During the time of 5—20 years, with the extension of time, the growth of average tree height and diameter at breast height (DBH) of P. radiata pure forest increased, but the number of shrub and herb species and vegetation coverage decreased gradually. The growth of average tree height and DBH of P. radiata and C. chengiana mixed forest was low, and the number of shrub and herb species under the forest had little change. The growth of average tree height and DBH of P. radiata, C. chengiana and R. pseudoacacia mixed forest increased slowly, but the species diversity and biomass of shrub and herb under the forest showed an upward trend. (3) In the practice of afforestation in the dry-hot valley of the Minjiang River, P. radiata, C. chengiana and R. pseudoacacia mixed forests with suitable density could be used as the main afforestation model. For the P. radiata pure forests to be tending, native tree species such as R. pseudoacacia, A. altissima and L.bicolor were preferred to be replanted after thinning to increase species diversity.