Amorpha Fruticosa Research Articles

Nitrogen input through chemical and biological pathway affects arbuscular mycorrhizal fungal communities in forage grass cultivation in southwest China

Exogenous nitrogen (N) input significantly affects arbuscular mycorrhizal fungi (AMF) in terrestrial ecosystems. However, how N input in leguminous plants and inorganic N fertilization affect AMF in forage grass cultivation is still unclear. AMF biodiversity indices and soil properties were measured after N fertilization and low or high density Amorpha fruticosa planting in forage grass cultivation areas under six treatments: control; A. fruticosa under low density (AFD1); A. fruticosa under high density (AFD2); N fertilization (N); A. fruticosa under low density with N fertilization (AFD1N); and A. fruticosa under high density with N fertilization (AFD2N). N fertilization in N and AFD1N treatments significantly increased AMF abundance in July. The highest AMF richness and Chao 1 values occurred in AFD2N and AFD2 treatments in December and July, respectively. The Glomus, Funneliformis, Claroideoglomus, and Septoglomus genera were the most abundant in all samples. Growth stage, legume density, N fertilization, and their interaction significantly impacted AMF community composition. AMF community composition differed significantly between N fertilization treatments (N, AFD1N, and AFD2N) and the control in December, and Septoglomus contributed to most of the changes by significantly decreasing in N fertilization treatments. Glomus contributed most to the A. fruticosa treatment changes, significantly decreasing in the AFD1 treatment in December and increasing in the AFD2 treatment in July compared to the control. AMF community composition at the genus level showed more species-pair interactions, and a higher negative correlation with a dominant driving force in Glomus, Funneliformis, Claroideoglomus, and Septoglomus in the N fertilization treatments. These results suggested that Septoglomus was sensitive to N fertilization while Glomus was sensitive to A. fruticosa N fixing. Higher inter-species competition in the relative abundant taxa among the N fertilization treatments compared to the A. fruticosa planting treatments and control highlighted the AMF community composition response to N input. Our findings provide guidance for the effective agricultural management of forage grass.

Responses of soil diazotrophs to legume species and density in a karst grassland, southwest China

Diazotrophs have potential for fixing atmospheric nitrogen (N) in terrestrial ecosystems. The effects of legumes on free-living N-fixing diazotrophs in the karst grassland were determined to provide a basis for ecosystem restoration. In a field experiment, diazotroph responses were examined in five treatments: control, low, and high densities of Amorpha fruticosa and Indigofera atropurpurea. The abundance and community composition of diazotrophs were significantly affected by sampling time and the interaction between different leguminous shrubs and planting density. Legume treatments significantly increased diazotroph abundance compared with the control in December (non-growing season). Greater N input with I. atropurpurea at high density in July (growing season) may suppress soil free-living N-fixing bacteria by decreasing diazotroph abundance. Diazotroph diversity was highest under I. atropurpurea in July. Phyllobacteriaceae and Beijerinckiaceae were abundant in the A. fruticosa plots, while Burkholderiaceae, Comamonadaceae, and Geobacteraceae were abundant in the I. atropurpurea plots. Regardless of the treatments, dissolved organic carbon was the key factor driving seasonal changes in diazotroph abundance and community composition. It suggests seasonal changes in temperature and soil moisture that drive nutrient availability (e.g., ammonium N and nitrate N) under planting legumes may explain the variation in diazotroph communities. Legumes reduced negative interactions among the species in network analyses. These findings suggest that increasing N availability by legume N fixation reduced inter-specific competition among the diazotrophs, with essential roles of rare taxa during the restoration of degraded lands in the karst region.

Nitrogen fertilizer and Amorpha fruticosa leguminous shrub diversely affect the diazotroph communities in an artificial forage grassland

Soil diazotrophs have been known to be essential in biological nitrogen (N) fixation, which contributes to the sustainability of agricultural ecosystems. However, there remains an inadequacy of research on the effects of different N inputs from N fertilization and from symbiotic N fixation associated with legumes on the diazotroph communities in agricultural ecosystems. Hence, we investigated the variations in diazotroph abundance and community composition as well as the soil properties with different N inputs in the Guimu-1 hybrid elephant grass cultivation on karst soils in China. We conducted six different N treatments: control, Amorpha fruticosa planting at a spacing of 1.5 × 2 m (AFD1), A. fruticosa planting at a spacing of 1 × 2 m (AFD2), N fertilization (N), A. fruticosa planting at a spacing of 1.5 × 2 m with N fertilization (AFD1N), and A. fruticosa planting at a spacing of 1 × 2 m with N fertilization (AFD2N). Our results showed that the interaction between sampling time and N fertilization significantly affected the diazotroph abundance. In July, the diazotroph abundance significantly decreased in the N fertilization treatments: N, AFD1N, and AFD2N, compared to that in the control. The richness and Chao1 estimator of diazotrophs significantly increased in AFD2N and AFD1 correspondingly in December and July, relative to those in the control. Co-occurrence networks showed species-species interactions with high negative correlations that occurred more in the control than in the N input plots. The N input from N fertilization and legume planting directly increased the ammonium N and nitrate N and consequently affected the dissolved organic N and pH of the soil, thereby altering the diazotroph abundance and richness. Our findings demonstrated that both N fertilization and legumes could reduce the interspecific competition among diazotroph species by providing greater N availability in the forage grass.

The non-native woody species of the flora of Ukraine: Introduction, naturalization and invasion

The process of invasion, naturalization, dispersion and invasive activity of non-native woody species in 5 regional floras, 5 urban floras and over 30 floras of the protected areas is discussed. It has been established that 182 non-native species out of 95 genera and 45 families are currently at different naturalization stages in the spontaneous flora of Ukraine. In terms of life-forms, they may be divided as follows: trees – 41%, shrubs – 35%, trees/shrubs – 15%, lianas – 9%. Most species spread both via seed dispersal and the vegetative way – 56%, using only seed dispersal – 42%, only the vegetative way – 2%. According to the preliminary rating of species-wise invasive activity, 71 species (40%) have naturalized completely, among them 20 invasive species, including 12 transformer species, 29 potentially invasive species, and 22 naturalized species which demonstrate no invasive tendencies. The initial stages of invasion of 111 species are as follows: introduction – 9%, survival – 36%, adaptation of the reproductive sphere – 28%, establishment, formative of local populations – 27%. In terms of dispersion, non-naturalized species are divided as follows: rare – 45%, local – 16%, sporadic – 6%, unique – 12%, spreading under control beyond collections and expositions in botanical gardens and arboretums – 21%. Twelve transformer species, the greatest threat to local diversity, are Acer negundo, Ailanthus altissima, Amorpha fruticosa, Bupleurum fruticosum, Elaeagnus angustifolia, E. rhamnoides, Fraxinus ornus, Parthenocissus quinquefolia, P. vitacea, Robinia pseudoacacia, Rhamnus alaternus, Salix × blanda and 8 invasive proper species: Berberis aquifolia, Colutea orientalis, Daphne laureola, Prunus cerasifera, P. serotina, Quercus ilex, Viburnum tinus, Vitis vinifera. The list of alien species, most widespread in 50 regions of Europe, includes Robinia pseudoacacia (42 regions), Ailanthus altissima (40), Acer negundo (38), Prunus cerasus (34), Quercus rubra (34), Rosa rugosa (34), Prunus domestica (31). The mitigation of the impacts of these species on local biodiversity is possible via the restoration of local native plant communities, land use organization, strict selection of introduced species prior to the introduction, culture of planting management, preventive measures and extending awareness and sharing of information about plant invasions. Therefore, Ukraine’s spontaneous flora is notable for the active process of naturalization of non-native woody species with considerable involvement of invasive alien species. This is the first and preliminary evaluation of the invasive activity of woody species in Ukraine’s flora. The manifestations of the global tendency of increased involvement and invasive activity of alien woody species in domestic flora have been confirmed. These conclusions are also relevant for elaborating the system of preventive, containing and mitigating measures regarding plant invasions in Ukraine.

Plants species for ecological landscaping in urban territory in Central Siberia

Green spaces such as parks and street trees represent a key component of urban ecosystems. Planting trees and shrubs in cities provides a number of environmental, economic, social and health benefits and also preserves biodiversity in highly urbanized areas. The key problem of the ecological landscaping in Central Siberia is to select plants species resistant both to high level of pollutants and to large variations in temperature. Basing on the comparative study of growth characteristics and physiological state of plants in natural and urban ecosystems we recommend 31 plants species of 16 families for ecological landscaping. Recommended species for ecological landscaping in Central Siberia are Abies sibirica, Acer platanoide, Amorpha fruticosa, Berberis thunbergii, Berberis vulgaris, Cornus alba, Cotoneaster lucidus, Crataegus sanguine, Dasiphora spp., Forsythia spp., Juglans mandshurica, Juniperus Sabina, Larix sibirica, Philadelphus spp., Physocarpus opulifolius, Picea obovata, Picea pungens, Pinus sibirica, Pinus sylvestris, Ribes aureum, Rosa rugosa, Salix alba, Salix ledebouriana, Salix purpurea, Sorbaria sorbifolia, Sorbus aucuparia, Spiraea salicifolia, Syringa josikaea, Tamarix ramosissima, Tilia cordata, Viburnum opulus. Coniferous plants are presented with 7 species of 5 genera. Deciduous plants are presented with 24 species of 21 genera. The list of recommended plants species includes both trees and shrubs.

INaturalist is an Unexploited Source of Plant-Insect Interaction Data

The aim of this study was to assess whether it is possible to extract useful interaction data between flowers and visiting insects using photographs from citizen science. Ultimately the longer-term aim is to understand possible impacts of invasive species on pollination networks. We used data from iNaturalist (https://www.inaturalist.org), GBIF (https://www.gbif.org), and GLOBI (https://www.globalbioticinteractions.org). From iNaturalist, we used photographs to extract flower visitation interactions. GBIF data were used for plant and pollinator occurrences, and GLOBI was used for information about known interactions between plants and pollinators. For this study we selected four plant species: Oxalis pes-caprae (Bermuda buttercup), Cirsium vulgare (spear thistle) Amorpha fruticosa (false indigo) and Lantana camara (common lantana). These species are relatively common, frequently photographed and known to be attractive to insects. All of these species are also considered invasive in different parts of world. We found that over 60% of all photographs identified as a picture of a bee (Apoidea) also showed a flower that the insect was visiting. Thirty-nine percent of butterflies (Papilionoidea) were photographed on a flower and 38% of Syrphidae. Currently, there are about 170,000 pictures of bees; 700,000 butterflies and 50,000 Syrphidae on iNaturalist from all over the world. This means there is a vast untapped resource of insect-plant interaction data on iNaturalist just waiting for exploitation. iNaturalist provides a standardized and cost-efficient enhancement to specimen collection, and it can be easily adapted for specific research goals. However, the relatively high rate of photographs without both species identifications (plant and visitor) highlights the importance of investing in resources to promote this approach and the importance of determining the identity of all species in a photograph.

(Mis) management of floodplain vegetation: The effect of invasive species on vegetation roughness and flood levels

Floodplains are prone to plant invasions, which increase their roughness and decrease their flood conveyance capacity. In recent decades, extremely high floods have occurred in the Tisza River (Hungary) without an increase in discharge. This could be partly explained by land cover changes, as plough fields and pastures have been replaced by forest plantations and invasive plants have become widespread in the Tisza River floodplain. The aims of the present research were (1) to evaluate long-term land cover changes from the point of view of floodplain roughness, (2) to calculate vegetation density with and without the invasive shrub Amorpha fruticosa, and (3) to model (HEC-RAS) the flood conveyance in the case of unmanaged and managed vegetation (eliminating invasive plants). The study was carried out at three floodplain sections of the Tisza and Maros rivers, Hungary.In the eighteenth century, wetlands (61–93%) covered the studied floodplain areas, but as a result of mid-nineteenth-century channel regulation works, pastures and plough fields (42–72%) became widespread, and riparian forests (8–19%) appeared. In the late twentieth century, poplar plantations (43–86%) replaced pastures and plough fields and provided a perfect habitat for invasive plants. As a result of these land cover changes, the mean vegetation roughness of the floodplains increased from 0.021–0.032 (1783) to 0.066–0.092 (2017). However, at-site measurements indicate considerably higher vegetation roughness values (0.093–0.134) when the invasive Amorpha is also considered. Invasive species clearance could decrease the vegetation roughness by 86%.Based on our modelled data, peak flood stages could be decreased by 13–34 cm after the clearance of invasive plants. However, these values are influenced by the floodplain slope and characteristics of the modelled flood wave. The management of longer floodplain sections would have a considerable effect on flood stages, while the clearance of smaller patches would not have this effect.

Effects of different legume species and densities on arbuscular mycorrhizal fungal communities in a karst grassland ecosystem

Legumes can increase nitrogen (N) input to soil via N2 fixation, and arbuscular mycorrhizal fungi (AMF) can colonize legumes, which further promotes the acquisition of nutrients such as phosphorus (P). Nevertheless, little is known about how different legume species or planting densities affect soil AMF communities. We measured soil AMF abundance, diversity, and community composition in two legume species that had been planted at two densities in a karst grassland. Five treatments were used: control (CK), Amorpha fruticosa at 1.5 × 2 m density (AFD1), A. fruticosa at 1 × 1 m density (AFD2), Indigofera atropurpurea at 1.5 × 2 m density (IAD1), and I. atropurpurea at 1 × 1 m density (IAD2). The results showed that A. fruticosa plots were significantly richer in Redeckera spp., while I. atropurpurea plots were richer in Septoglomus. AMF abundance in AFD1, AFD2, and IAD1 was significantly higher than in CK, but AMF abundance in IAD2 was significantly lower than that in the other treatments. AMF richness and Chao1 estimator in AFD1 were significantly higher than in CK. Funneliformis, Septoglomus, and Acaulospora were significantly more abundant in IAD2 than in the other treatments. The interaction between legume species and density had a significant effect on AMF abundance and community composition. AMF abundance and diversity were significantly negatively and positively correlated with available P and microbial biomass N, respectively. These results suggest that different species and densities of legumes may increase available N, which could improve AMF abundance and alleviate soil P deficiencies. Planting A. fruticosa or I. atropurpurea at a low density may be an effective method to increase AMF colonization of roots, and thus, nutrient transport in karst grasslands.

Growth and physiological responses to successional water deficit and recovery in four warm-temperate woody species.

Plant responses to drought and their subsequent rehydration can provide evidence for forest dynamics within the context of climate change. In this study, the seedlings of two native species (Vitex negundo var. heterophylla, Quercus acutissima) and two exotic species (Robinia pseudoacacia, Amorpha fruticosa) to China were selected in a greenhouse experiment. The gas exchange, stem hydraulic parameters, plant osmoprotectant contents and antioxidant activities of the seedlings that were subjected to sustained drought and rehydration (test group) as well as those of well-irrigated seedlings (control group) were measured. The two native species exhibited a greater degree of isohydry with drought because they limited the stomatal opening timely from the onset of the drought. However, the two exotic species showed a more 'water spender'-like strategy with R. pseudoacacia showing anisohydric responses and A. fruticosa showing isohydrodynamic responses to drought. Severe drought significantly decreased the leaf gas exchange rates and hydraulic properties, whereas the instantaneous water use efficiency and osmoprotectant contents increased markedly. Most of the physiological parameters recovered rapidly after mild drought rehydration, but the water potential and/or supply of nonstructural carbohydrates did not recover after severe drought rehydration. The results demonstrate that the xylem hydraulic conductivity and shoot water potential jointly play a crucial role in the drought recovery of woody plants. In brief, the native species may play a dominant role in the future in warm-temperate forests because they employ a better balance between carbon gain and water loss than the alien species under extreme drought conditions.

The anti-invasive activity of Robinia pseudoacacia L. and Amorpha fruticosa L. on breast cancer MDA-MB-231 cell line

The paper investigates anticancer effects of methanol extracts of invasive plant species Robinia pseudoacacia L. (RpE) and Amorpha fruticosa L. (AfE) on breast cancer MDA-MB-231 and healthy MRC-5 cells. The anticancer activity was evaluated through examination of cytotoxic effects, anti-invasive potential and impact on redox status in comparative analysis using their chemical composition. According to the IC50 values, the investigated plants had no significant cytotoxic effects either on healthy cell line MRC-5 or on MDA-MB-231 cancer cells, but they showed great anti-invasive potential by suppressing all investigated parameters of tumor invasion and metastases (Matrix Metalloproteinases (MMP), protein concentration and MMP-9, C-X-C Motif Chemokine Ligand 12 (CXCL-12), Vascular Endothelial Growth Factor (VEGF-A) and Hypoxia-Inducible Factor (HIF-1α) gene expression) in MDA-MB-231 cells. Based on their remarkable anti-invasive potential, RpE and AfE are suitable for use as potential supplements in anticancer therapy or as nutritional food supplements.

Phytosociology, Distribution and Ecology of a Willow Community with False Tamarisk from the Lotru Valley (Romanian Carpathians)

The overall objective of this research was to contribute to a better knowledge of the phytosociology, ecology and distribution of the plant community formed by Myricaria germanica (false tamarisk) and the willow species Salix purpurea. This plant community has an important role in reducing the speed and strength of the water flow during floods. The description was based on cover‐abundance data for the faithful, dominant, characteristic and companion species of this plant community. A predominance of Myricaria germanica was observed when analysing the phytocoenoses, as the species finds in this area favourable ecological conditions for an abundant development. Salix purpurea presents a small abundance-dominance or in some phytocoenoses may even lack. The field research also revealed the excessive development of the species Calamagrostis pseudophragmites in some areas, related mostly with the effect of human activities. The anthropogenic disorders have induced modifications in the floristic physiognomy and compositions of the phytocoenoses, favouring also the invasion of opportunistic species such as Ambrosia artemisiifolia, Impatiens glandulifera, Phytolacca amearicana, Amorpha fruticosa, Erigeron annuus, which continuously extend in the studied territory. As Myricaria germanica and Salix purpurea phytocoenoses suffer a great decline throughout Europe, the habitat built by these species was declared of interest and was included in the Habitats Directive.
 
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 In press - Online First. Article has been peer reviewed, accepted for publication and published online without pagination. It will receive pagination when the issue will be ready for publishing as a complete number (Volume 47, Issue 3, 2019). The article is searchable and citable by Digital Object Identifier (DOI). DOI link will become active after the article will be included in the complete issue.
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An experimental study exploring the influencing factors for ultrasonic-assisted extraction of flavonoid compounds from leaves of Amorpha fruticosa L.

In this paper, the ultrasonic-assisted extraction process of flavonoid compounds from leaves of Amorpha fruticosa is optimized. In single factor experiments, solid/liquid ratios, ultrasonic power, ethanol concentrations and extraction cycles were experimental factors. Box–Behnken central composite design and RSM analyzed the effects of the four factors on the yield of total flavonoids. The optimal extraction parameters were solid/liquid ratio 1:50 g/mL, ultrasonic power 316 W, ethanol concentration 50%, 4 extraction cycles. In the optimized condition, the estimated value of the regression model was 66.6456 mg/g while the measured value was 66.4329 mg/g.

Influence of vegetation restoration on matrix structure and erosion resistance of iron tailings sites in eastern Hebei, China

The effects of vegetation restoration on matrix structure and erosion resistance of iron tailings were studied at dump sites in Malanzhuang, Qian’an, Hebei province, China. The restoration process involved soil spray sowing restoration model with Rhus typhina, soil and iron tailings admixture spray sowing restoration model with Amorpha fruticosa Linn. and six-hole brick restoration model with Pinus tabulaeformis Carriere.–Amorpha fruticosa Linn. mixed-forest, and direct restoration model with Hippophae rhamnoides and Sabina vulgaris. Results show that the composition and distribution of particles and aggregates were closely related to erosion resistance (P A. fruticosa soil and iron tailings admixture spray sowing > mixed-forest six-hole brick > H. rhamnoides direct restoration > S. vulgaris direct restoration. The R. typhina soil spray sowing restoration model resulted in the greatest improvement in matrix structure of iron tailings, increasing the clay (10.6%) and large particle aggregates (18.7%) contents significantly (P < 0.01). Simultaneously, particle population, grading conditions (Cu = 28.86, Cs = 1.65), and aggregate stability (6.02) were significantly improved. The A. fruticosa soil and iron tailings admixture spray sowing restoration model, which effectively improved particle distribution (Cu = 8.51, Cs = 1.07), increased the number of large aggregates considerably (9.6%), thereby increasing aggregate stability (6.2). The six-hole brick model significantly increased the number of large aggregates (4.0%) and improved the stability of aggregates (6.2). H. rhamnoides direct restoration improved the stability of aggregates (5.1) but showed no other significant improvements. The effect of S. vulgaris direct restoration on matrix structure of iron tailings was not significant. Due to its dependence on matrix structure of iron tailings, the erosion resistance of R. typhina soil spray sowing restoration model was the greatest, while that of S. vulgaris direct restoration was the weakest. There was no significant difference in the erosion resistance of the other models. Overall, vegetation restoration supplemented by soil spray sowing restoration and engineering measures is superior to in situ direct vegetation restoration in the short-term. In-situ direct restoration has long-term ecological significance because of its advanced concept of near-natural restoration and the advantages of low cost, easy operation, and low secondary damage.

Effects of re-vegetation type and arbuscular mycorrhizal fungal inoculation on soil enzyme activities and microbial biomass in coal mining subsidence areas of Northern China

Coal mining subsidence leads to the degradation of vegetation cover and reduces soil quality. Soil microbes play a critical role in the recycling of soil nutrients and soil fertility. Both arbuscular mycorrhizal fungi (AMF) and artificial re-vegetation play key roles in regulating biogeochemical systems. Here, we investigated the effects of AMF inoculation and artificial re-vegetation type on soil invertase, urease and alkaline phosphatase activities, soil microbial biomass carbon (MBC), soil microbial biomass nitrogen (MBN), and their correlations with soil physicochemical properties using redundancy analysis and partial redundancy analysis in order to enhance and reclaim soil quality and the ecological efficiency of coal mining subsidence areas. The results show that soil nutrients and soil enzyme activities in FM (inoculated with Funneliformis mosseae) soils were significantly higher than in control (uninoculated) soils under all re-vegetation types, and soil organic carbon content (SOC) was highest in Hippophae rhamnoides (HR) soils. Soil MBC followed the order HR > Amorpha fruticosa (AF) > Xanthoceras sorbifolium (XS) > Cerasus humilis (CH). Soil total nitrogen (TN), dissolved organic nitrogen (DON) and nitrate nitrogen (NO3—N) were key factors affecting soil microbial activity in the FM soils, whereas SOC, DON, and soil C/N ratio were the important factors in control soils. Soil microbial activity was affected by soil factors to different degrees. AMF are essential for plant acquisition of soil resources, especially soil nitrogen. AMF were correlated with the potential activities of N acquisition enzymes in soil and affected N cycling in the coal mining subsidence soils.

Фітоценотична характеристика угруповань із участю Amorpha fruticosa (Fabaceae) у Середньому Придніпров’ї (Україна)

Фітоценотична характеристика угруповань із участю Amorpha fruticosa (Fabaceae) у Середньому Придніпров’ї (Україна)

Medonosne biljke u kanalskoj mreži Banata

This paper aims to point out the presence and distribution of honey plants along the canal network of the Banat region, and the relationship between their basic ecological (ecological group, ecological indices) and biological (life form, flowering time, pollination) characteristics. A total of 18 honey plants were observed, dominated by hemicryptophytes and phanerophytes (over 70%). Species Salix alba, Populus alba and invasive species Amorpha fruticosa were found along the largest number of canals. Correlation and PCA analyses determined that the flowering time of the honey plants depends on their ecological group, plant life form and habitat characteristics (pH, temperature, light, aeration, the nutrients content in the soil). Forest, wetland and woody plants have a shorter flowering time, compared with weed-ruderal species. Twelve species are invasive in Europe, while Acer negundo and Amorpha fruticosa are highly invasive species in Serbia. It has been ascertained that honey species which are not invasive in Serbia (but in the wider Europe region they are) are often recommended for planting, which can lead to their more intensive spread and increase the possibility of them becoming invasive in our country.

Allelopathic potential of selected woody species growing on fly-ash deposits

The objective of this study was to determine the allelopathic potential of Robinia pseudoacacia L., Ailanthus altissima (Mill.) Swingle and Amorpha fruticosa L. that grow on the fly-ash deposits at the ?Nikola Tesla ? A? thermoelectric power plant in Obrenovac. The chemical characteristics of fly ash, such as pH, electrical conductivity (EC), content of carbon (C) and nitrogen (N), contents of available phosphorus (P2O5) and potassium (K2O), the contents of total and available Fe, Cu, Mn, Ni and Zn as well as of phenolic acids (3,5 dihydroxybenzoic acid (3,5-DHBA) and ferulic acid) and flavonoids (rutin and quercetin) were analyzed in control fly ash (bare zones without vegetation cover) and plant rhizospheric fly ash. In order to determine the allelopathic activity of phenolic compounds in fly ash, modified soil sandwich allelopathic biotests were performed, and Trifolium pratense L. (red clover) was used as the indicator species. A. fruticosa showed the highest allelopathic activity, followed by A. altissima whereas R. pseudoacacia showed the lowest allelopathic potential. Negative correlation was noted between radicle and hypocotyl growth inhibition of red clover and the pH of fly ash. Positive correlations were found between radicle growth inhibition and the content of C, P2O5, total concentrations of Cu, available concentrations of Mn and Ni, the contents of ferulic acid, 3,5-DHBA, and rutin. Our results indicate that A. fruticosa and A. altissima increased the content of phenolics in fly ash, which can act as allelochemicals leading to radicle growth inhibition of red clover in the pioneer plant community on fly-ash deposits. These woody species that colonized fly-ash deposits can initiate the beginning of pedogenetic processes altering the ecosystem processes at degraded sites.

Nanocellulose-Graphene Oxide Hybrid Aerogel to Water Purification

The depletion of non-renewable resources and pollution of industrial wastewater are major challenges to the human security. Using green renewable resources to address the above problems coincides with the sustainable development of human society. In this study, we attend to design hybrid aerogel, derived from nanocellulose and graphene oxide (GO), to realize wastewater purification via adsorption behavior, benefitting from its high specific surface area and high porosity. Nanocellulose, isolated from Amorpha fruticosa Linn. as a shrub plant, and graphene oxide were combinely employed to prepare the hybird aerogel via freeze-drying process; and its purification ability to remove methylene blue(MB), congo red (CR) and waste oil in waste water was tested. The results indicate that the isolated nanocellulose bears abundant hydroxyl groups and high aspect ratio of ~500 with average diameter of ~30 nm, which is well distributed on the surface of graphene oxide sheet with side length of about 1~3 μm, both of which form the hybrid aerogel with porosity larger than 99%. The nanomaterials physically assemble its orignial aggregation state. When the mass ratio of nanocellulose and graphene oxide is 8 : 2, the hybrid aerogel reaches the highest adsorption capacity of 265.6mg/g and 21.5mg/g for MB and CR, respectively. The hybrid aerogel after hydrophobic treatment shows excellent oil adsorption capacity up to 25.6 g/g, which is beneficial to oil/water separation. This strategy provides potential great-application of the nanocellulose in water purification.

ROBINIA PSEUDOACACIA L. AND AMORPHA FRUTICOSA L. АS HEAVY METALS PHYTOREMEDIATION

A large amount of heavy metals leads to environmental pollution. Heavy metals are part of the land or may arise as a result of human products. Affecting the normal growth and development of plant systems and only to a certain limit concentrations of metals. Increasing these suitable and permitted a value to metals in the soil leads to changes in the composition and appearance of the environment in a negative direction. To eliminate or reduce elevated concentrations of heavy metals and their adverse effects on the environment, many researchers focus their attention on finding species that can act as scavengers soil and phytoremediations. There are a large number of plant species that are capable of survival on such surfaces, whether it comes to wild species or species that are on the site with the aim planted. The best known and the most common fitoremedijatori by woody species are Acacia (Robinia pseudoacacia L.) and its most closely related to indigo ( Amorpha fruticosa L.). Its advanced adaptation and the possibility of survival in the soil rich with heavy metals, are plant species that are used in order to protect the environment from the adverse effects of heavy metals. These species have developed ability to adapt, and thereby can perform the accumulation of heavy metals from the soil. They absorb these metals or through the root system, through the tree to the leaves and flowers or leaves through the metal while returning the return direction. In this way, that is, the accumulation of metals that are present in concentrations higher than allowed for stay vegetation, stored and purified by environmental influences damaging of elements which are present in the air and in the soil.

Allelopathic Effects of Aqueous Leaf Extracts from Four Shrub Species on Seed Germination and Initial Growth of Amygdalus pedunculata Pall.

This study aimed to screen out the shrub species which can promote the seed germination and seedling growth of Amygdalus pedunculata Pall. and offer insight for ecological environment governance of the coal mines subsidence area in Mu Us Sandy Land, Yulin City of Shaanxi Province. The indoor bioassay method was used to study the aqueous leaf extracts from Amorpha fruticosa Linn., Hedysarum mongolicum Turez., Sabina vulgaris Ant., and Hippophae rhamnoides Linn. under different concentration gradients to examine seed germination, initial growth, and physiological and biochemical of two Amygdalus pedunculata varieties (YY-1 from Yuyang County (YY) and SM-6 from Shenmu County (SM), Shaanxi Province, China). The results showed that with aqueous leaf extracts concentrations at lower concentrations of 0.025 (T1) and 0.05 g·mL−1 (T2) from A. fruticosa, H. mongolicum, and S. vulgaris significantly promoted seed germination and seedling growth of two A. pedunculata varieties. Moreover, H. rhamnoides aqueous leaf extracts had the strongest inhibitory effect on seed germination and seedling growth of A. pedunculata, and death occurred at concentrations of 0.15 (T4) and 0.20 g·mL−1 (T5). The enzyme activity and chlorophyll content of the A. pedunculata leaves decreased with an increase in the aqueous leaf extracts concentration of the four shrubs; the change trend of malondialdehyde content was the opposite. Root activity of the A. pedunculata increased and then decreased. The H. mongolicum and S. vulgaris are the most suitable mixed tree species for YY-1, while H. mongolicum and A. fruticosa are the most suitable mixed tree species for SM-6 at a relatively low density with more security. The results provide a theoretical basis and technical support for the establishment of an artificial mixed forest of A. pedunculata in the coal mine subsidence area of Mu Us Sandy Land.