Plant Diversity Composition Research Articles

Impact of transforming karst mountainous forests into urban parks on plant diversity patterns.

The conversion of urban montane forest resources into urban parks requires careful assessment to understand its impacts on plant diversity over time. This study aims to enhance urban biodiversity conservation strategies by analyzing how habitat type and park age affect woody plant diversity. We surveyed woody plant species in 60 sample plots across two different habitats (remnant forest vs. artificial green space) within three mountain parks in Guiyang, China, established at different times. The alpha diversity of saplings/seedlings was significantly higher in remnant forests than in artificial green spaces. Artificial green spaces exhibited more homogenous woody plant composition compared with remnant forests. Newer parks showed greater variation in plant composition between the two habitats than older parks. Indicative species in remnant forests were predominantly native, whereas those in artificial green spaces were mainly ornamental species. The transformation of karst mountainous forests into urban parks leads to the homogenization of woody plant composition and impedes the regeneration of saplings/seedlings. Therefore, it is crucial to manage these conversions carefully and strive to preserve as many native species as possible to support urban plant diversity conservation.

Phytochemical and Agronomic Characterization of High-Flavonoid Lettuce Lines Grown under Field Conditions.

Flavonoids are antioxidant phytochemicals that confer a beneficial effect on human health. We have previously developed and characterized eight lettuce (Latuca sativa L.) lines that accumulated high levels of diverse flavonoids and their precursors in controlled environment conditions. Three Rutgers Scarlet lettuce (RSL) lines selected in tissue culture for deep-red color (RSL-NAR, RSL-NBR, RSL-NFR) accumulate anthocyanins and quercetin, three lines identified in a chemically mutagenized red lettuce population accumulate kaempferol (KfoA and KfoB) or naringenin chalcone (Nco), and two lines that were spontaneous green mutants derived from the red line RSL-NAR (GSL, GSL-DG) accumulate quercetin. These eight lines were field-grown in the Salinas Valley of California for four years together with seven control accessions of varying colors (light green, dark green, red, and dark red). At market maturity, a substantial variation in plant composition was observed, but the three RSL lines consistently accumulated high levels of cyanidin, GSL and GSL-DG accumulated the highest levels of quercetin, KfoA and KfoB accumulated kaempferol, and Nco amassed naringenin chalcone, confirming that these mutant lines produce high levels of beneficial phytochemicals under field conditions. Mutant lines and control accessions were also assessed for their biomass production (plant weight, height, and width), overall content of pigments (leaf chlorophyll and anthocyanins), resistance to diseases (downy mildew, lettuce drop, and Impatiens necrotic spot virus), postharvest quality of processed tissue (deterioration and enzymatic discoloration), and composition of 23 mineral elements. All but one mutant line had a fresh plant weight at harvest comparable to commercial leaf cultivars; only Nco plants were significantly (p < 0.05) smaller. Therefore, except for Nco, the new, flavonoid hyperaccumulating lines can be considered for field cultivation.

Variation in plant composition along a gradient of increasing distance from wells in a mountain steppe in southern Mongolia

Habitat degradation and heavy grazing by livestock are common conservation challenges across the steppes of Mongolia and Central Asia. Livestock grazing patterns are generally not uniform and are typically greater near campsites and watering holes. In this study, we examined how plant composition in a mountain steppe in southern Mongolia varied along a gradient of increasing distance from wells. We found that the cover and average height of Ephedera prezewalskii increased with increasing distance from the wells whereas soil chemistry and the other variables of plant composition that we examined were similar along the gradient of increasing distance from the wells. These results suggest relatively limited impact of livestock grazing on plant composition in our study. However, our study was limited in space and time and further studies are needed to understand the impact of livestock grazing in this mountain steppe in southern Mongolia.

Impacts of open‐pit coal mining and livestock grazing on plant diversity in a steppe: From the perspective of remote sensing

AbstractCoal mining and grazing cause land degradation. Plant diversity loss is one of the characteristics. Ground surveys cannot analyze the effects of mining and grazing on plant diversity in large areas, and remote sensing offers a novel solution. The aims of this study were as follows: (1) to analyze the impacts of mining and grazing on plant diversity composition by considering α‐, β‐, and γ‐ diversity comprehensively; (2) to determine the impacts of mining and grazing on the spatial distribution of α‐diversity; (3) to identify priority areas for ecological restoration. We applied a novel remote sensing method to obtain plant α‐, β‐, and γ‐ diversity maps and performed spatial analysis. The results were as follows: (1) mining reduced the proportion of α‐diversity in the total diversity (γ‐diversity) but increased that of β‐diversity. Grazing increased the proportion of α‐diversity but decreased that of β‐diversity. Mining increased the heterogeneity among plant communities, whereas grazing increased the homogeneity. (2) Both mining and grazing reduced α‐diversity. With increasing distance from the mine, α‐diversity increased logarithmically. (3) The severely affected range of mining on plant diversity is approximately 325 m. When there is grazing around the mine, the severely affected range is approximately 400 m. Severely affected areas are priority areas for ecological restoration. Improving the soil quality can be an effective measure. This study gains new insights into the effects of coal mining and grazing on plant diversity. These findings can provide some guidance for governments to formulate ecological restoration measures in mining areas.

Which regionalization scheme is the best to predict wetland plant distribution in Western Patagonia?

AbstractQuestionsGiven the current multiplicity of threats to pond biodiversity, there is a clear need to examine which environmental drivers determine the composition and distribution of species. Using wetland plants as pond biodiversity surrogates, two questions led to this work: How do wetland plant species assemblages and abundance vary across local‐ and regional‐scale classification schemes in wetlands? How does wetland plant beta‐diversity vary within these wetland classification schemes?LocationWestern Patagonia, Argentina, from 36°S to 56°S and from 73°W to 65°W.MethodsWetland plant distribution constrained by water and climatic factors was analyzed using canonical correspondence analysis. Variance partitioning analysis was performed to assess which classification scheme (phytogeographical units, wetland regions, wetland genesis and hydrogeomorphological types) better explained variation in plant composition. An IndVal analysis was also carried out to detect taxa with the highest association values (indicator taxa) for the different categories of wetland classification. Beta‐diversity was calculated to evaluate variation patterns within classification schemes.ResultsPlant distribution was mainly related to site location across the latitudinal gradient, following a decreasing pattern of air temperature from northern to southern wetlands. Variance partitioning analysis confirmed the effectiveness of a regional‐scale classification (wetland regions) in predicting plant associations, and the IndVal analysis also highlighted this classification scheme above the remainder, sustaining the highest number of indicator taxa. Wetland plant beta‐diversity patterns were explained by relatively high species turnover, with species composition showing low nestedness values.ConclusionClimate factors rather than local characteristics were the main drivers of plant distribution at the wide regional scale analyzed. Wetland region (classification based on climatic criteria) was the most effective scheme in predicting plant associations and sustaining the highest number of indicator taxa. Also, ponds located in the Patagonian Andes and those with a glacigenic origin contribute most to the regional wetland plant diversity. Therefore, these aspects should be taken directly into account in the future delineation of protected areas to increase the resilience of Patagonian wetland habitats and their associated biota, and to maintain the ecosystem services that they provide.

Global patterns and drivers of rainfall partitioning by trees and shrubs.

Spatiotemporal redistribution of incident rainfall in vegetated ecosystems results from the partitioning by plants into intercepted, stemflow, and throughfall fractions. However, variation in patterns and drivers of rainfall partitioning across global biomes remains poorly understood, which limited the ability of climate models to improve the predictions of biome hydrological cycle under global climate change scenario. Here, we synthesized and analyzed the partitioning of incident rainfall into interception, stemflow, and throughfall by trees and shrubs at the global scale using 2430 observations from 236 independent publications. We found that (1) globally, median levels of relative interception, stemflow, and throughfall accounted for 21.8%, 3.2%, and 73.0% of total incident rainfall, respectively; (2) rainfall partitioning varied among different biomes, due to variation in plant composition, canopy structure, and macroclimate; (3) relative stemflow tended to be driven by plant traits, such as crown height:width ratio, basal area, and height, while relative interception and throughfall tended to be driven by plant traits as well as meteorological variables. Our global assessment of patterns and drivers of rainfall partitioning underpins the role of meteorological factors and plant traits in biome-specific ecohydrological cycles. We suggest to include these factors in climate models to improve the predictions of local hydrological cycles and associated biodiversity and function responses to changing climate conditions.

Chemistry of medicinal plants as an integral part of ecological education

The degree of variability in the composition of herbal medicines was studied on the example of the preparation of St. John's wort from various Ukrainian producers. The Cu and Zn contents were the most stable compared to other (Fe, Mn, Co, Cr, Ni, Pb, Cd) microelements among plants of different origins. The content of toxic elements (Pb, Cd) did not exceed the established standards. Meanwhile, a 2-3-fold concentration difference was observed for hyperforin, an active pharmaceutical ingredient in St. John’s wort. Thus, the existing standards do not ensure the stability of the composition of herbal preparations. As a result, the quality of medicinal drugs can be significantly different. The key reason for the variation in plant composition is environmental influence, including anthropogenic factors. Existing training programs for prospective specialists of the pharmaceutical industry do not pay enough attention to the impact of the environment on the quality of herbal raw materials. Necessary changes to the syllabi of relevant disciplines are formulated to eliminate this shortcoming and ensure sustainable development of raw materials sources for the pharmaceutical industry.

Trade-offs for butterfly alpha and beta diversity in human-modified landscapes and tropical rainforests.

The accelerating expansion of human populations and associated economic activity across the globe have made maintaining large, intact natural areas increasingly challenging. The difficulty of preserving large intact landscapes in the presence of growing human populations has led to a growing emphasis on landscape approaches to biodiversity conservation with a complementary strategy focused on improving conservation in human‐modified landscapes. This, in turn, is leading to intense debate about the effectiveness of biodiversity conservation in human‐modified landscapes and approaches to better support biodiversity in those landscapes. Here, we compared butterfly abundance, alpha richness, and beta diversity in human‐modified landscapes (urban, sugarcane) and natural, forested areas to assess the conservation value of human‐modified landscapes within the Wet Tropics bioregion of Australia. We used fruit‐baited traps to sample butterflies and analyzed abundance and species richness in respective land uses over a one‐year period. We also evaluated turnover and spatial variance components of beta diversity to determine the extent of change in temporal and spatial variation in community composition. Forests supported the largest numbers of butterflies, but were lowest in each, alpha species richness, beta turnover, and the spatial beta diversity. Sugarcane supported higher species richness, demonstrating the potential for conservation at local scales in human‐modified landscapes. In contrast, beta diversity was highest in urban areas, likely driven by spatial and temporal variation in plant composition within the urban landscapes. Thus, while improving conservation on human‐modified landscapes may improve local alpha richness, conserving variation in natural vegetation is critical for maintaining high beta diversity.

The relationship of vegetation and soil differentiation during the formation of black-soil-type degraded meadows in the headwater of the Qinghai-Tibetan Plateau, China

In alpine meadow ecosystems, considerable spatial heterogeneity in forb-dominant vegetation exists as a result of severe grassland degeneration; however, there is limited quantitative information on the vegetative differences between degenerated and pristine grasslands. Therefore, a field study, which seeks to identify the edaphic factors driving the variation in plant composition and distribution, was conducted in a severely degraded alpine meadow located in the Qinghai-Tibetan Plateau, NW China. Five meadows, an original meadow and four degraded meadows, were used to determine the differentiation and relationships between the vegetation and soil of degraded alpine meadows. The dominated species of these degraded meadows are Ligularia virgaurea–Artemisia gmelinii (LA), Oxytropis ochrocephala–Leontopodium nanum (OL), Aconitum pendulum–Potentilla anserina (AP) and Stellera chamaejasme–Artemisia nanschanica (SA), respectively. The results indicate that vegetation cover, grass biomass, species number and diversity indices clearly decrease from the original to the degraded meadow. Soil water, clay and nutrient content are also reduced with grassland degradation in surface and subsoil layers. The joint study of floristic and edaphic variables confirms that the soil features, especially the bulk density, sand content, pH, salinity, N and K, mainly determine the establishment of vegetation in the severely degraded fields of this study. These results may be useful for alpine grassland ecosystem restoration and management.

Adaptation of plant functional group composition to management changes in calcareous grassland

It is the aim of plant functional research to generate general rules of species assembly and species reactions based on plant functional traits. Here we determined plant functional groups that are important with regard to land use types (grazing, mowing, mulching, burning, abandonment) and looked for mechanisms leading to changes in species composition after management changes in calcareous grasslands. To filter out the set of traits which best described the variation in plant composition along the studied land use gradient and to identify functional groups we chose an iterative three-table ordination method. We included traits related to persistence as well as traits describing the germination niche of a plant. To gain insight into underlying mechanisms which led to differing importance of these plant functional groups at different management regimes we investigated shifts in dominance of the identified functional groups at eight management regimes using long-term vegetation data of a site which was grazed before the onset of different management regimes in 1974. Ongoing unidirectional changes in cover of the four determined functional groups at most of the treatments indicated that even after almost 30 years new equilibria of functional group composition were still not reached. The study showed that other management treatments but grazing and mowing led to changes in functional group composition, which were mainly driven by increasing dominance of a highly competitive species group.

Local Variation in Diet Composition of the Japanese Serow During Winter

We investigated local geographical variation in the plant composition and quality (crude protein) of the diet of the Japanese serow (Capricornis crispus) by analyzing rumen contents. We collected the rumen contents from 111 Japanese serows culled for pest control between January and March 1997 in Shizuoka Prefecture, central Japan. The composition of the diet, characterized by a high proportion of browse (65.2%), including green plant leaves (55.3%), confirmed that the Japanese serow is a typical browser, at least in winter. Although the composition of the diet varied geographically even within Shizuoka Prefecture (i.e. the northern populations included less green broad leaves, and more grasses and Sasa spp.), altitude did not affect the composition. Latitudinal variation in plant composition of the diet was explained by a shift in plant availability within vegetation zones from evergreen broad-leaf to deciduous broad-leaf forests. Lack of variation in the diet plant composition with changes in altitude may be explained by probably greater altitudinal than latitudinal variation in the territories of the Japanese serow, and by greater individual variation in food habits. Diet quality remained at a constant high level regardless of altitudinal and latitudinal variation in diet plant composition. This suggests that the Japanese serow maintains a high-quality diet by selective feeding, which is possible only when the serow is at low population density and in possession of a territory.