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1.
Identification of medicinal plants by their molecular signature is a fast growing tool. The identification of Desmodium gangeticum (L.) DC. (Shalparni, a constituent of Ayurvedic formulation “Dashmoolarishtha”) was carried out using genomic approach. Authentic samples of D. gangeticum(L.) DC., D. velutinum (Willd.) DC. and D. triflorum (L.) DC. were analyzed and compared to commercial samples of various origin. Within twenty primers used, eleven gave 223 RAPD fragments. RAPD profiles of three species showed very low similarity index (0.21–0.39), whereas market samples showed high similarity of 0.82–0.89 with authenticated D. gangeticum.  相似文献   

2.
Disturbance is a key factor affecting plant species richness and it has been hypothesized that species richness reaches a peak some time after disturbance occurs. Managed boreal forests are characterized by large scale disturbance in the form of clear-cuttings, which partly resembles natural disturbance regimes. The young stands however, which may be important to many plants, are often homogenous and dense compared to naturally regenerated stands. We examined previously unstudied effects of disturbance, succession and management practices on plant species richness in boreal forests. Survey data covering the northern and central parts of Sweden (4465 plots) were used to compare species richness and composition in four stand maturity classes—“cutting”, “young”, “pre-mature” and “mature”, and two fertility classes—“rich” and “poor”. In addition, the effect of thinning was examined in young and pre-mature forests.  相似文献   

3.
Fundamental to herbal medicine quality is the use of 'authentic' medicinal herb species. Species, however, 'represent more or less arbitrary and subjective man-made units'. Against this background, we discuss, with illustrative examples, the importance of defining species boundaries by accommodating both the fixed (shared) diagnostic and varying (within-species) traits in medicinal herb populations. We emphasize the role of taxonomy, floristic information and genomic profiling in authenticating medicinal herb species, in addition to the need to include within species phytochemical profile variations while developing herbal extract identification protocols. We outline the application of species-specific genomic and phytochemical markers, chemoprofiling and chemometrics as additional tools to develop qualifying herbal extract references. We list the diagnostic traits available subsequent to each step during the medicinal herb extract manufacturing process and delineate limits to qualification of extract references.  相似文献   

4.
A herbal preparation “Compound Codyceps-TCM-700C (CC-700C)” was tested for hepatoprotective effect against the carbon tetrachloride induced liver damages in Sprague-Dawley rat model for a period of 6-weeks. Two dosage levels of CC-700C, respectively 286.2 mg/kg-bw (L-TCM) and 2862 mg/kg-bw (H-TCM), and a positive control Silymarin (Sigma) were used to compare their therapeutic effect. Both CC-700C's and Silymarin showed nontoxic in nature, as evidenced by body weight gain, organ weights and appearance including liver, spleen, and kidney. The activities of aspartate aminotransferase (AST) and alanine-aminotransferase (ALT) were more effectively suppressed by CC-700C than Silymarin. In addition, all levels of serum bilirubin, serum albumin, triglyceride (TG), total cholesterol (TC), platelet count (PLT), and prothombin time (PT) except TG were shown effectively restored to normal values by CC-700C and Silymarin. Moreover, although levels of glutathione (GSH), glutathione reductase (GSH-Rd), and superoxide dismutase (SOD) were equally maintained by these three preparations, glutathione peroxidase (GSH-Px) was suppressed only by H-TCM, and SOD only by Silymarin. In contrast, the activity of catalase efficiently recovered to control level on administration of CC-700C, being far better than Silymarin. Finally the liver collagen content, an indication of fibrosis, was also significantly suppressed by CC-700C, better effect was by L-TCM, but both levels were superior to Silymarin. Conclusively, the herbal preparation “Compound Cordyceps TCM-700C” is a potent hepatoprotective preparation. For therapeutic use, a dosage of 286.2 mg/kg-bw would be sufficiently effective.  相似文献   

5.
Even though considerable parts of the global tropical forests are located in Africa, reliable data on African forest resources is limited. While this is widely recognized for tropical moist forests, it also holds for tropical dry forests. To partially fill the gap a forest inventory was carried out in Burkina Faso, West Africa. In this paper we present a methodological approach and sample based estimates of the tree and forest resources including estimates of (1) land cover classes, (2) species composition, and (3) above ground tree carbon stocks. Following the land classification of the Food and Agriculture Organization of the United Nations (FAO), the forest cover of Burkina Faso was estimated as 42.6% (116,847 km2). For the classes “other wooded land”, “other land” and “other land with tree cover” the estimates were 1.6%, 53.6%, and 9.1%, respectively. We found notable differences to the estimates published by FAO, in particular when considering the classes “forest” and “other wooded land” separately, but lesser so when the two classes are combined. That points to a major issue in applying these class definitions in semiarid environments. Given the relatively small sample size (n = 46 field observed plots), relative standard errors (SE%) of area estimates are high (around 9% for the larger area classes). Aboveground tree carbon stocks were estimated to be 6.640, 5.580 and 7.222 Mg ha−1 for “forest”, “other wooded land” and “other land with tree cover”, respectively (SE% around 18% for all three estimates). Availability of biomass models is very limited for all classes, in particular when it comes to shrubs. Furthermore, it was estimated that the most abundant tree species in Burkina Faso is Vittelaria paradoxa, the “shea butter tree” which is a multi-use tree species of high relevance for rural livelihoods.To our knowledge this study is the first field-based forest inventory on national level in Burkina Faso where the estimation of errors was possible on statistical grounds, and done. The results of this study revealed major issues that should be taken into account when doing similar studies, including carbon monitoring and accounting: increasing the sample size will lead to smaller standard errors (at a higher costs, of course), but will not solve the crucial points (1) of non-availability of suitable biomass models, in particular for shrub lands and (2) of implementation issues regarding the definition of land cover types.  相似文献   

6.
Chen CC  Chuang PH  Chen YS  Yao CH  Chen HM 《Fitoterapia》2011,82(8):1249-1257
Intestinal α-glucosidase performs a physiologically vital function in the digestive process of dietary carbohydrates. Administration of an α-glucosidase inhibitor may retard the digestion and absorption of carbohydrates. Consequently, the rise in postprandial blood glucose could be suppressed. This study developed a novel technology, called “after flowing through immobilized receptor (AFTIR),” for targeting components in herbal medicines with α-glucosidase-suppressing capability. As a result, we reveal that the AFTIR system is a highly-efficient drug screening platform, capable of purifying and identifying active components with α-glucosidase-suppressing capability in herbal medicines.  相似文献   

7.
Ethanolic extracts of diploid Artemisia dracunculus L. (wild tarragon) from populations in the U.S., and polyploid tarragon from a variety of sources, were screened for the anti-diabetic compounds davidigenin; sakuranetin; 2’,4’-dihydroxy-4-methoxydihydrochalcone; 4,5-di-O-caffeoylquinic acid; 5-O-caffeoylquinic acid and 6-demethoxycapillarisin using LC-MS. Only decaploid plants contained all six target compounds and were the only plants that contained davidigenin and 2,4-dihydroxy-4-methoxydihydrochalcone. These results exhibit the importance of germplasm selection and provenance when studying plants for medicinal activity. Relying only on the “right species” for consistent medicinal activities may not be sufficient, as intraspecific variation may be highly significant.  相似文献   

8.
Understory herb communities in the Southern Appalachians are among the highest biodiversity plant communities in North America. In the mid-1990s, a debate began over whether understory herb communities recover to their pre-disturbance states following logging. Studies showing reduced herb-layer diversity in previously logged forests were criticized for not accounting for intersite environmental heterogeneity. More recent studies have addressed environmental heterogeneity, but have neglected long-term recovery by using “mature forests” as young as 80 years old as the benchmark for diversity comparison, even though old growth stands have disturbance return intervals exceeding 500 years. Here we address concerns clouding previous studies of high-diversity Appalachian herb communities and investigate their long-term recovery by comparing paired sites of old growth forest and forest logged 100–150 years ago. We found that species richness and individual abundance is greater in old growth forests than mature forests and that species composition differed significantly between the two. Turnover in species among old growth and mature forests accounted for 11% of the total species richness and was significantly greater than expected. Species turnover at intermediate (5–50 m) and landscape-scales (>10 km) contributed the most towards total species richness. Herb communities in rich cove forests have successional trajectories that exceed 150 years, with important community changes still occurring long after the forest returns to what has been previously termed a “mature” state. To conserve the diverse herb layer, we conclude that mature forest stands are too young to serve as baselines for recovery, landscape-scale preservation of multiple forest stands is needed to maximize species richness, and maintaining 100–150-year logging rotations will likely lead to loss of biodiversity.  相似文献   

9.
There is a widespread view that forest plantations with exotic species are green deserts, unable to sustain biodiversity. Few studies have demonstrated, however, that planted stands of exotic trees have a greater negative effect on the plant diversity of savanna vegetation. We compared the native woody flora under four stands of slash pine of about 45 years old with four stands where the previously existing native Cerrado vegetation was preserved and protected from disturbances for the same period, has changed into dense vegetation - the “cerradão”, at Assis municipality, São Paulo State, Brazil. Aiming at understanding the potential ecological filters driving these communities, we assessed air and soil humidity, light availability and classified the native species on the basis of shade tolerance, dispersal syndrome and biomes in which they occur (Atlantic Forest or Cerrado). We recorded an average of 70 (±13) species under pine stands and 54 (±16) species in cerradão. Of the total of 136 species recorded, 78 occurred in both habitats, eight were exclusive to the “cerradão” (shade tolerant and also occurring in forest ecosystems) and 18 were recorded only under pine stands (82% heliophytic, exclusive to the Cerrado biome). Among the functional attributes and abiotic variables analyzed, only light availability explained the floristic differences found. Since richness was higher under pine, we refuted the hypothesis that exotic species constrain the establishment of the native species richness in the understory. On the other hand, the dark environment under the closed-canopy of the “cerradão” acts as a filter inhibiting the establishment of typical Cerrado species. Since pine stands, if managed in long cycle, maintain a reasonable pool of Cerrado endemic species in the understory pine plantations may be a good starting point for savanna restoration.  相似文献   

10.
A survey of medicinal plants used by the ethnic communities of Dibru-Saikhowa Biosphere Reserve in Northeast India has been reported. Fifty-five plant species belonging to 34 families and 52 different genera were included. For each plant species, botanical name, vernacular name, part(s) used, popular medicinal use, forms of preparation and applications of the herbal remedies are provided.  相似文献   

11.
Traditional systems of medicine have become a topic of global importance recently. Increased commercialization of economically important medicinal plants has resulted in overharvesting, threatening their survival. The present study was carried out to document the indigenous uses of medicinal plants by the local communities in and around Rema-Kalenga Wildlife Sanctuary, Bangladesh. Data collection was predominantly qualitative recording the species use, identifying their relative importance (RI) and assessing the informants’ consensus factor (Fic) on associated knowledge. We interviewed 140 households of the local community and 5 local herbal practitioners. A total of 44 plant species were in use to treat 33 ailments under 10 broad disease categories. Five species were found to have high use versatility (RI > 1), Emblica officinale L. being the most versatile. Respiratory problems scored the highest Fic value (0.56) involving the use of 30% of the species recorded. Terminalia bellerica Roxb., Sterculia villosa Roxb., Dillenia pentagyna Roxb. and Terminalia arjuna Bedd. were being harvested commercially. Use by the community, particularly for subsistence consumption, seemed to be sustainable, but commercial extraction of some species appeared unsustainable. Buffer zone-based commercial farming of medicinal plants with a commercial value could serve a dual purpose of assuring sustainable alternative income generation for local communities as well as conserving the natural resources in protected areas.  相似文献   

12.
Each year, forest fires destroy about 500,000 ha of vegetation in Europe, predominantly in the Mediterranean region. Many large fires are linked to the land transformations that have taken place in the Mediterranean region in recent decades that have increased the risk of forest fires. On the one hand, agricultural fallows and orchards are slowly being colonized by vegetation, and on the other hand, the forest is not sufficiently used, both of which result in increased accumulation of fuel. In addition, urbanization combined with forest extension results in new spatial configurations called “wildland-urban interfaces” (WUI). WUI are commonly defined as “areas where urban areas meet and interact with rural lands, wildland vegetation and forests”. Spatial analyses were performed using a WUI typology based on two intertwined elements, the spatial organization of homes and the structure of fuel vegetation. The organization of the land cover in terms of representativeness, complexity or road density was evaluated for each type of WUI. Results showed that there were significant differences between the types of WUI in the study area. Three indicators (i) “fire ignition density”, derived from the distribution of fire ignition points, (ii) “wildfire density”, derived from the distribution of wildfire area and (iii) “burned area ratio”, derived from the proportion of the burned area to the total study area were then compared with each type of WUI. Assuming that the three indicators correspond to important aspects of fire risk, we showed that, at least in the south of France, WUI are at high risk of wildfire, and that of the different types of wildland-urban interfaces, isolated and scattered WUI were the most at risk. Their main land cover characteristics, i.e. low housing and road densities but a high density of country roads, and the availability of burnable vegetation such as forested stands and shrubland (garrigue) explain the high fire risk. Improving our knowledge of relationships between WUI environments and fire risk should increase the efficiency of wildfire prevention: to this end, suitable prevention actions and communication campaigns targeting the types of WUI at the highest risk are recommended.  相似文献   

13.
The nature of “climate change” will differ with geographical regions and its final impact on ecosystems vary with the extent of temperature increase, changes in irradiance and levels of UVB, amount and patterns of precipitation and humidity, and alterations in the incidence and nature of abiotic disturbances. Despite many uncertainties, there is consensus in the fact that global warming already has and will have impact on the temporal and spatial dynamics of insect herbivores. Ectothermic organisms are affected by the changes in environmental conditions directly in dispersal, reproduction, development and mortality, and indirectly through altered plant nutritional quality, resistance and via community interactions. Ambiguous consequences are to be expected depending on the individual host plant and herbivore species, probably involving altered incidence and intensity of pest outbreaks and changes in distributional ranges. Regions that represent northern or upper limits of occurrence, such as the Alps or the boreal zone, are likely to be affected most by an increase in stability and population density of certain pest species, such as defoliating insects or bark beetles. At the same time, temperature increase and drought will render areas of distribution in southern and continental parts of Europe less suitable for heat susceptible species, which will probably not only result in northwards shifts, but range contractions. The review is based on chapters of the “Study on impacts of climate change on European forests and options for adaptation” led by the European Forest Institute (Efi) and on results of the EU project “PROMOTH - Global change and pine processionary moth: a new challenge for integrated pest management”. Thaumetopoea pityocampa serves as illustrative example for insect herbivores whose latitudinal and altitudinal distribution is mainly controlled by temperature and already modified by global warming.  相似文献   

14.
The composition and structure of riparian forests in the coast redwood region were analyzed in relation to the length of time since timber harvest, and the width of riparian buffer zone. Ten sites were sampled in the central range of the coast redwood forest type within a variety of post-harvest age groups and riparian buffer zone widths. Data was collected using randomly selected sample plots adjacent to perennial coastal steams. Correlation Fisher's r to z tests and two-tailed t-test were used to examine the relationship between the sample variables and the experimental parameters “years since harvest”, and “width of buffer.” Results indicate that canopy cover was negatively correlated to “years since harvest” with the highest level of canopy cover found on the youngest sites and the lowest level found on the old-growth sites. The hardwood to conifer dominance ratio and the basal area of Alnus rubra (red alder) were correlated negatively to both “years since harvest” and “buffer width” indicating that timber harvest favored hardwood species. Late seral associates such as Oxalis oregana (redwood sorrel), Anthyrium filix-femina (lady fern), and Vaccinium parviflorum (billberry) were found preferentially in older forests and sites with wider buffer zones, while non-native species such as Hedera helix (English ivy), Pampas cortedaria (pampas grass), and Myosotis latifolia (forget-me-not) were found preferentially in younger forests and areas with smaller buffer zones.  相似文献   

15.
Windward slopes of the inland mountain ranges in British Columbia support a unique inland temperate rainforest (ITR) ecosystem. Increasing fragmentation and the loss of old ITR stands have highlighted the need for determining conservation biology priorities among remaining old forest stands. We have addressed this issue by surveying foliose macrolichens within 53 old ITR stands in British Columbia's 135,000 ha very wet-cool interior-cedar hemlock (ICHvk2) biogeoclimatic subzone in the upper Fraser River watershed. Study plots were stratified by leading tree species and by “wet” versus “dry” relative soil moisture conditions. Other plot variables included: temperature, precipitation, incident solar loading, and canopy openness. Ordination plots showed a distinct assemblage of foliose cyanolichens, including Lobaria pulmonaria, Lobaria retigera, Sticta fuliginosa, Nephroma isidiosum, Nephroma occultum, and Pseudocyphellaria anomala, whose abundance was correlated with increasing relative soil moisture, temperature, canopy openness, precipitation, and basal area of spruce. Logistic regression models similarly identified relative soil moisture and temperature in all parsimonious models. Leading tree species, in combination with “wet” relative soil moisture and/or temperature, were important factors explaining the presence or absence of five (Cavernularia hultenii, L. retigera, N. occultum, Platismatia norvegica, and Sticta oroborealis) of the eight modeled old-growth associate lichen species. This combination of conditions favouring the development of canopy lichen communities in old forests was best expressed in low elevation water receiving sites. We hypothesize that groundwater availability in these sites promotes species richness and abundance of canopy lichens by creating more favourable conditions for growth, and by reducing fire return intervals which allows for the accumulation of rare species over time. Historically, forests in these wet “toe-slope” positions were disproportionately targeted for logging. Their conservation should now be a high priority, given their disproportionate significance to maintaining canopy lichen diversity in the present-day landscapes.  相似文献   

16.
This paper reports the results of an ethnobotanical survey of medicinal plants used by the Thari people of the Nara Desert, Sindh, Pakistan. Fifty-one plant species distributed across 28 families and 43 genera were discovered to have medicinal uses by local inhabitants of the Nara Desert. Twenty-one of those species are proposed to have new uses not recorded in the Indo-Pak folk herbal medicinal literature. Boraginaceae and Amaranthaceae were the most dominant families (5 species; 2 and 4 genera, respectively) of medicinal plants, followed by Asteraceae, Capparidaceae, Convolvulaceae, Poaceae, Scrophulariacea and Zygophyllaceae. About 44 types of ailments were treated with various parts of the 51 medicinal plant species. For treating ailments, the use of the whole plant was higher (53%) than leaves (18%), roots (14%) and fruits (10%) alone.  相似文献   

17.
Rapid conversion of lodgepole pine (Pinus contorta) dominated landscapes in western Alberta to a mosaic of successional stand ages has long-term implications for elk populations in the region that have not been fully assessed. We developed stand-level models of forage succession using data from 159 cutblocks to simulate forage and cover availability within the home range of an elk under “even-flow” and “pulsed” timber cutting scenarios that are common in this area. We found forage biomass peaked approximately 9 years following felling for both herbaceous (graminoids and forbs) and palatable browse forage. Forage production was determined primarily by the age of the cutblock (time since felling) and to a lesser extent elevation, compound topographic index (a measure of site wetness), and the distance to the nearest deciduous forest patch. Forbs became increasingly abundant as stands matured. Browse composition shifted from palatable species to unpalatable species after approximately 30 years. Within an elk home range (100 km2), we found that simulating an “even-flow” cutting regime resulted in forage availability that was always higher than under the current conditions of 90% forests when more than 10 ha were harvested per year. Further, forest cover (>30>30-year-old stands) was never less than the guideline of 60% of the area needed to provide adequate thermal and hiding cover. In contrast, when a “pulsed” harvest scenario was simulated, similar to what occurs for mountain pine beetle control, forage availability changed dramatically over time as a large cohort of harvested timber aged. Without further harvesting the stand conditions in the home range eventually returned to a state of pre-harvest risk for mountain pine beetle outbreak. We demonstrated several additional harvesting scenarios that avoided the potential risk and produced a much higher level of forage than currently exists.  相似文献   

18.
Clearance of understory to enhance the recreational value of the forest is common in urban woodlands. Open forests are generally perceived as safe and pleasant, but clearance is likely to be negative for woodland birds as the shrub layer is important for foraging and protection. In this 3-year experiment with a before after control impact (BACI) design, the effects from understory clearance on woodland bird abundance and diversity in five suburban broadleaved forests in south-western Sweden were studied. Understory clearance was either made in regular patches, with 50% removal of understory, or as “Complete” (90%) removal. Adjacent stands of equal size were left unmanaged as controls. Woodland birds and understory vegetation were surveyed before and after the management. The total density of breeding forest birds decreased in the plots with “Complete” removal of the understory compared to plots with “Patchy” clearance. “Patchy” clearance had no significant effect on bird density. Bird diversity was not affected by the management. Woodland birds are highly valued animals in urban green areas and the impact on bird fauna should therefore be taken into consideration in the development of management plans for urban woodlands. The present study has demonstrated that clearance of understory can have negative effects on bird abundance if carried out over large areas. Clearance in patches was not found to have negative effects on bird abundance and can promote recreational values by increasing visibility and structural variation of the forest.  相似文献   

19.
Biodiversity and the lexicon zoo   总被引：1，自引：0，他引：1  
Ecologists and natural resource managers struggle to define and relate biodiversity, biocomplexity, ecological integrity, ecosystem services, and related concepts; to describe effects of disturbance dynamics on biodiversity; and to understand how biodiversity relates to resilience, resistance, and stability of ecosystems and sustainability of resource conditions. Further diversifying this “lexicon zoo” are the ecological roles of rare species and refugia, and measures of surrogates and indicators of biodiversity parameters. To impart order on this lexicon zoo, a “concept map” framework is suggested for clearly defining biodiversity parameters and related terms, relating biodiversity to ecosystem services and sustainability, describing how disturbance affects biodiversity, and identifying biodiversity parameters for management and monitoring. Many relations among these concepts are poorly understood in managed forest environments and are presented here as testable tenets.  相似文献   

20.
In this study, we identified the distribution characteristics of a mixed forest of coniferous and broad-leaved trees (a typical forest type in Hokkaido, Japan) using landscape metrics and topographic factors, and attempted to apply this knowledge to examine forest management. This approach provides a new perspective (i.e., the landscape structure) on forest management, which traditionally has been determined on the basis of individual forest stands. We first created a cover type map of the study area by means of aerial photo interpretation. The characteristics of each cover type identified from the photographs were determined using landscape metrics for each cover class. We digitized a forest administrative map (1:20,000 scale) using 20-m contours, and imported this into GIS software to produce a terrain model; on this model, we overlaid the cover types. Our examination of landscape metrics showed that most of the natural forest could be managed similarly. However, our examination of topographic characteristics revealed exceptions (e.g., areas that are difficult to regenerate) that will require particular attention when managing the natural forest. Based on the information we obtained, we proposed a guideline for sustainable forest management. From the land cover map, we proposed an “improved” cover type map to illustrate the development of a high growing stock of forest based on forest management. We compared the current cover map with the “improved” cover map and demonstrated that the improved form would have more significant effects on fauna that do not recognize differences in the proportion of the dominant species types than on those that can recognize these differences. Our results show how the information obtained using landscape metrics and terrain models is an essential tool for various stages of forest management planning.  相似文献   

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