Xerophytic Plants Research Articles

Does seed size and surface anatomy play role in combating phytotoxicity of nanoparticles?

Rapid utilization of nano-based products will inevitably release nanoparticles into the environment with unidentified consequences. Plants, being an integral part of ecosystem play a vital role in the incorporation of nanoparticles in food chain and thus, need to be critically assessed. The present study assesses the comparative phytotoxicity of nanoparticle, bulk and ionic forms of zinc at different concentrations on selected plant species with varying seed size and surface anatomy. ZnO nanoparticles were chosen in view of their wide spread use in cosmetics and health care products, which allow their direct release in the environment. The impact on germination rate, shoot & root length and vigour index were evaluated. A concentration dependent inhibition of seed germination as well as seedling length was observed in all the tested plants. Due to the presence of thick cuticle on testa and root, pearl millet (xerophytic plant) was found to be relatively less sensitive to ZnO nanoparticles as compared to wheat and tomato (mesophytic plants) with normal cuticle layer. No correlation was observed between nanoparticles toxicity and seed size. The results indicated that variations in surface anatomy of seeds play a crucial role in determining the phytotoxicity of nanoparticles. The present findings significantly contribute to assess potential consequences of nanoparticle release in environment particularly with major emphasis on plant systems. It is the first report which suggests that variations observed in phytotoxicity of nanoparticles is mainly due to the predominant differences in size and surface anatomy of tested plant seeds and root architecture. Effect of various concentrations of nano ZnO, bulk ZnO and zinc sulphate on the growth of pearl millet (A), tomato (B) and wheat (C) seedlings.

MONITORING OF SEASONAL VARIATION IN LATEX OF Calotropis procera AIT. AND Calotropis gigantea L.R.Br USING FTIR SPECTROSCOPY

Background: Calotropis procera Ait and Calotropis gigantea L.R.Br of Family Asclepiadaceae are xerophytic plants which are found abundantly in arid zones of India. Their latex has been attributed with many pharmaceutical and therapeutic values and is being included either as a single drug or as an ingredient of many compound Ayurvedic formulations. Classical texts of Ayurveda recommend a specific collection protocol for crude drug collection depending on the parts used and rutu (season). Collection of latex has been advocated in Sharada (autumn) rutu (season). Objective: The objective of the present study was to assess the influence of six seasons, according to Ayurveda, on the organic profile of latex of C procera and C gigantea by using FTIR. Material and Methods: The crude latex of both species of Calotropis were collected in clean glass vials regularly in all the six rutu i.e Vasanta (March-April),Grishma (May-June), Varsha(July- August), Sharada (September- October), Hemanta (November- December) and Shishira (January- February) from a single plant and then packed in autoclaved appendorfs and sent for FTIR analysis. Observations and results: The differentiation in FTIR was remarkable in Grishma rutu and thus supports the theory that seasons do influence the organic profile of the latex.

Culturable Facultative Methylotrophic Bacteria from the Cactus Neobuxbaumia macrocephala Possess the Locus xoxF and Consume Methanol in the Presence of Ce3+ and Ca2.

Methanol-consuming culturable bacteria were isolated from the plant surface, rhizosphere, and inside the stem of Neobuxbaumia macrocephala. All 38 isolates were facultative methylotrophic microorganisms. Their classification included the Classes Actinobacteria, Sphingobacteriia, Alpha-, Beta-, and Gammaproteobacteria. The deduced amino acid sequences of methanol dehydrogenase obtained by PCR belonging to Actinobacteria, Alpha-, Beta-, and Gammaproteobacteria showed high similarity to rare-earth element (REE)-dependent XoxF methanol dehydrogenases, particularly the group XoxF5. The sequences included Asp301, the REE-coordinating amino acid, present in all known XoxF dehydrogenases and absent in MxaF methanol dehydrogenases. The quantity of the isolates showed positive hybridization with a xoxF probe, but not with a mxaF probe. Isolates of all taxonomic groups showed methylotrophic growth in the presence of Ce3+ or Ca2+. The presence of xoxF-like sequences in methylotrophic bacteria from N. macrocephala and its potential relationship with their adaptability to xerophytic plants are discussed.

Desertification risk assessment and management program

Risk assessment provides the possibility of planning and management to prevent and reduce the risk of desertification. The present study is aimed to assess the hazard and risk of desertification and to develop management programs in the semi-arid western regions of Golestan Province in Iran. Desertification rate was obtained using the Iranian model of desertification potential assessment. Since the rating system was considered for the indicators, data analyses were carried out according to the Mann-Whitney test. The risk of desertification was calculated based on hazard, elements at risk and vulnerability assessment maps. The intensity of desertification was estimated to be medium. Among the factors affecting desertification, agriculture by the weighted average of 3.22 had the highest effect, followed by soil, vegetation, water and wind erosion criteria by weighted averages of 2.45, 2.32, 2.15 and 1.6 respectively. Desertification risk assessment results also showed that about 78% of central and northern parts of the region, with the largest population and residential centers, surface and underground water resources, agriculture and horticulture, is confronted with a high to very high degree of risk. Management plans and control measures, based on risk values were presented in four activities (with two management priorities under critical and non-critical conditions). For the management program with the largest area. Control measures and strategies such as the establishment of halophytic and xerophytic plants, drainage networks, resilient facilities and infrastructure were proposed. Reducing the risk of desertification, could play a crucial role in the sustainable development of drylands and desert ecosystems.

A Review on Ethnobiological & Medicinal Potential of Capparaceae Family Plant: Capparis decidua (Forssk.) Edgew

Rajasthan state is rich in flora of xerophytic plants. Capparis decidua (Forssk.) Edgew. is a wild bushy plant found in hot arid regions. This plant has wide range of distribution in many parts of India. Ethnobiologically, this plant is useful as its various parts like immature flower buds, semi-mature fruits, young shoots with small leaves are pickled for use as a condiment and traditional people use this plant in treating ailments like digestive diseases, anodyne, sudorific, constipation, gout, cough, flu, dropsy, palsy, asthma, and intestinal worms, lumbago, odontalgia. Capparis decidua (Forssk.) Edgew. contains chemical compounds like alkaloids, flavanoids, terpenoids, phenolic compounds, steroids, vitamins, quarternary ammonium compounds and many more phytoconstituents that are responsible for its medicinal value. Different parts of this plant like seed, root, stem, flowers, fruits and leaves have medicinal importance and has shown numerous pharmacological activities like antimicrobial, antibacterial, antifungal, anti-inflammatory, antioxidant, hepatoprotective, anthelmintic, antidiabetic, antisebum, antihyperlipidemic, antisclerotic, antitermite, antiplaque, analgesic, sedative and anticonvulsant. Economic importance of this plant has tended for harvesting, yield and marketing specifically in Thar Desert. Future potential of this crop is very promising as it is a drought and heat tolerant plant which makes it a good weather forecasting species; also it provides people with food (pickle & vegetable), fodder, wood and fuel. The presence of numerous phytoconstituents makes it a medicinally important crop for treating deadly diseases. This review covers taxonomy, distribution, phytochemicals, and nutritional value, and commercial value, traditional and pharmacological aspects of Capparis decidua (Forssk.) Edgew.

Growth, hydrolases and ultrastructure of Fusarium oxysporum as affected by phenolic rich extracts from several xerophytic plants

Fusarium oxysporum, the causal agent of rot and wilt diseases, is one of the most detrimental phytopathogens for the productivity of many economic crops. The present study was conducted to evaluate the potentiality of some xerophytic plants as eco-friendly approach for management of F. oxysporum. Phenolic rich extracts from five plants namely: Horwoodia dicksoniae, Citrullus colocynthis, Gypsophila capillaris, Pulicaria incisa and Rhanterium epapposum were examined in vitro. The different extracts showed high variability in their phenolic and flavonoid contents as well as total antioxidant capacity. A strong positive correlation existed between the antifungal activity of the tested extracts and their contents of both total phenolics and flavonoids (r values are 0.91 and 0.82, respectively). Extract of P. incisa was the most effective in reducing the mycelial growth (IC50=0.92mg/ml) and inhibiting the activities of CMCase, pectinase, amylase and protease by 36, 42, 58 and 55%, respectively. The high performance liquid chromatography analysis of P. incisa extract revealed the presence of eight phenolic acids along with five polyphenolic compounds. The flavonol, quercetin and its glycosides rutin and quercetrin were the most abundant followed by the phenolic acids, t-cinnamic, caffeic, ferulic and vanillic. P. incisa extract not only affects the growth and hydrolases of F. oxysporum but also induces ultrastructure changes in the mycelium, as revealed by transmission electron microscopy. To our knowledge, this is the first study to investigate the mechanisms underlying the antifungal activity of P. incisa.

Spatial genetic structure of forest and xerophytic plant species in arid Eastern Central Asia: insights from comparative phylogeography and ecological niche modelling

Central Asia is one of the major arid regions of the world, and the spatial genetic structure of plant species in this area displays broad significance with respect to the understanding of plant evolution and biogeographical patterns of temperate arid lands. Although the genetic structure of some plants has been examined in previous studies, it remains mostly unconfirmed whether different plants in the same habitat have similar genetic structure, and the factors that have influenced structure in plants of the region are also unknown. Accordingly, we employed the approaches of molecular phylogeography and species distribution modelling to compare spatial genetic structure and ecological niches for three montane forest and four lowland xerophytic plants in East Central Asia. The results obtained suggest that the three forest species retreat westward during the Last Glacial Maximum as indicated by higher genetic differentiation in western populations. By contrast, multiple peaks of genetic differentiation were detected from chloroplast DNA datasets among populations in each of the four xerophytic species. Based on nuclear ribosomal internal transcribed spacer datasets, anemophilous pollination had shaped the high dispersal ability for pollen-mediated gene flow and outcrossing pollination had triggered extensive heterozygosity among populations. In conclusion, palaeoclimatic changes and species traits have mainly influenced the spatial genetic structure of forest and xerophytic plants in arid Eastern Central Asia.

Identification of drought response genes in Zygophyllum xanthoxylum by suppression subtractive hybridization

Drought is an important abiotic stress that seriously limits plant growth and crop productivity in some regions of the world. Zygophyllum xanthoxylum, a succulent xerophyte species with excellent adaptability to adverse arid environments, is an excellent model system for the study of the molecular mechanisms behind drought tolerance in xerophytic species. To better understand the molecular basis of Z. xanthoxylum responses to drought stress and to isolate drought tolerance-related genes from Z. xanthoxylum, we constructed a cDNA library from Z. xanthoxylum and screened the library for stress-related genes by PCR-based suppression subtractive hybridization (SSH). A total of 637 expressed sequence tags were generated by sequencing 672 randomly selected clones, resulting in the identification of 338 unigenes comprising 77 contigs and 261 singlets. The unigenes were assigned to 13 functional categories, such as metabolism, disease- or defense-related genes and energyrelated gene. In addition, we analyzed the expression patterns of 24 genes associated with drought stress-responsive pathways by real-time RT-PCR. The results indicated that osmolyte biosynthesis genes, reactive oxygen scavengers, transporters, signaling components and transcription factors play important roles in drought stress responses. This study provides a valuable resource for studying the drought tolerance mechanism of this xerophytic plant species.

Verification of Geometric Model-Based Plant Phenotyping Methods for Studies of Xerophytic Plants.

This paper presents the results of verification of certain non-contact measurement methods of plant scanning to estimate morphological parameters such as length, width, area, volume of leaves and/or stems on the basis of computer models. The best results in reproducing the shape of scanned objects up to 50 cm in height were obtained with the structured-light DAVID Laserscanner. The optimal triangle mesh resolution for scanned surfaces was determined with the measurement error taken into account. The research suggests that measuring morphological parameters from computer models can supplement or even replace phenotyping with classic methods. Calculating precise values of area and volume makes determination of the S/V (surface/volume) ratio for cacti and other succulents possible, whereas for classic methods the result is an approximation only. In addition, the possibility of scanning and measuring plant species which differ in morphology was investigated.

Postglacial vegetation history of Orcas Island, northwestern Washington

The revegetation of islands following retreat of Pleistocene glaciers is of great biogeographical interest. The San Juan Islands, Washington, feature regionally distinctive xerophytic plant communities, yet their vegetation history, as it relates to past climate and sea level, is poorly known. We describe a 13,700-year-old pollen record from Killebrew Lake Fen and compare the vegetation reconstruction with others from the region. The data suggest that the narrow channels surrounding Orcas Island were not a barrier to early postglacial immigration of plants. Between 13,700 and 12,000 cal yr BP, Pinus, Tsuga, Picea, Alnus viridis, and possibly Juniperus maritima were present in a mosaic that supported Bison antiquus and Megalonyx. The rise of Alnus rubra-type pollen and Pteridium spores at ca. 12,000 cal yr BP suggests a warming trend and probably more fires. Temperate conifer taxa, including Cupressaceae, Pseudotsuga, Tsuga heterophylla, and Abies, increased after 11,000 cal yr BP and especially in the last 7000 cal yr BP. After 6000 cal yr BP, Pseudotsuga and Cupressaceae dominated the vegetation. The last 1500 yr were the wettest period of the record. Due to its rain shadow location, Orcas Island experienced drier conditions than on the mainland during most of the postglacial period.

Rainfall effects on the sap flow of Hedysarum scoparium.

In arid and semi-arid areas, plant physiological responses to water availability depend largely on the intensity and frequency of rain events. Knowledge on the responses of xerophytic plants to rain events is important for predicting the structure and functioning of dryland ecosystems under changing climate. The sap flow of Hedysarum scoparium in the Mu Us Sand Land was continuously measured during the growing season of 2012 and 2013. The objectives were to quantify the dynamics of sap flow under different weather conditions, and to examine the responses of sap flow to rain events of different sizes. The results showed that the daily sap flow rates of H. scoparium were lower on rainy days than on clear days. On clear days, the sap flow of H. scoparium showed a midday plateau, and was positively correlated with solar radiation and relative humidity. On rainy days, the sap flow fluctuated at low levels, and was positively correlated with solar radiation and air temperature. Rain events not only affected the sap flow on rainy days through variations in climatic factors (e.g., solar radiation and air temperature), but also affected post-rainfall sap flow velocities though changes in soil moisture. Small rain events (<20 mm) did not change the sap flow, whereas large rain events (>20 mm) significantly increased the sap flow on days following rainfall. Rain-wetted soil conditions not only resulted in higher sap flow velocities, but also enhanced the sensitivity of sap flow to solar radiation, vapor pressure deficit and air temperature.

Meiotic chromosome behavior of Haworthia limifolia

Haworthia limifolia is a xerophytic plant belonging to the family Liliaceae and is indigenous to Africa. It is use extensively for its medicinal properties like antibacterial, antifungal properties and used for the treatment of sores, superficial burns, as a blood purifier and to promote pregnancy in women and cattles. In present investigation chromosomal behaviour of H. limifolia in meiosis was studied. In diplotene stage chiasmata was observed showing the possibilities of genetic recombination. Chromosome clumps were observed in diakinesis indicating sticky nature of chromosomes. Meiotic abnormalities like stickiness, precocious movement, formation of bridges and laggards were also reported in both meiosis I and II. A fairly high percentage of pollen sterility that is 73.41% was recorded resulting in failure of fruit formation. This plant could be designated as facultative apomict (Swanson, 1957) as the only means of reproduction found was asexual or vegetative.

Geographical isolation caused the diversification of the Mediterranean thorny cushion-like Astragalus L. sect. Tragacantha DC. (Fabaceae)

Understanding the origin and evolution of Mediterranean vascular flora within the long-term context of climate change requires a continuous study of historical biogeography supported by molecular phylogenetic approaches. Here we provide new insights into the fascinating but often overlooked diversification of Mediterranean xerophytic plants. Growing in some of the most stressing Mediterranean environments, i.e. coastal and mountainous opened habitats, the circum-Mediterranean Astragalus L. sect. Tragacantha DC. (Fabaceae) gathers several thorny cushion-like taxa. These have been the subjects of recent taxonomical studies, but they have not yet been investigated within a comprehensive molecular framework. Bayesian phylogenetics applied to rDNA ITS sequences reveal that the diversification of A. sect. Tragacantha has roots dating back to the Pliocene, and the same data also indicate an eastern–western split giving rise to the five main lineages that exist today. In addition, AFLP fingerprinting supports an old east–west pattern of vicariance that completely rules out the possibility of a recent eastern origin for western taxa. The observed network of genetic relationships implies that contrary to what is widely claimed in the taxonomic literature, it is range fragmentation, as opposed to a coastal-to-mountain ecological shift, that is likely the main driver of diversification.

The Productivity and Structure of Sage (Salvia L.) Populations in the Territories of Lesser Caucasus Range

18 populations of Salvia species are selected in the fitocenological complexes of the regions of Lesser Caucasus range (Nakhchivan AR and north-east regions of LC ). In these populations, the fitocenological state of 4 species (S.limbata, S.sclarea, S.verticulata və S.tesquicola) which are belonged to the breed, is estimated,their reserves are found out and the dynamics of the productivity in the ontogeny is determined.It is known that, in the populations, individuals belonged to the g1 və g2 phases of the ontogeny are more and at the same phase, the plant gives more product. Sage (Salvia L.) breed is one of the representatives of Lamiaceae (Lamiaceae Lindl.) family.27 species of the breed spread in the flora of Azerbaijan. 19 species of them spread in the flora of the Nakhchivan AR, and 12 species in the central, northern and eastern regions of Lesser Caucasus.Two of these territories – central and south are under Armenian occupation, that is why, only the population structure of the species in the north-east is found out. 9 species from 19 species which are come across in the flora of the Nakhchivan AR are merely characteristic for the region. 4 species which are come across in the north-east regions of Lesser Caucasus and in the autonomous republic, are selected and each of the species is in the surround of Lesser Caucasus range[nakh cons]. Referring to the literature,among them, S.limbata is not noted in the north-east regions of LC, but during the reserches, the same species are come across in the lower and central mountainous zones of the territory and in the dry stony-rocky slopes. It is a xerophyte plant, the territory is a new spreading field for it. In “Tartar” region, its new population is noted. Its other populations are noted in “Goranboy” and “Dashkesen” regions. 5-6 populations of the plant are setted in the Nakhchivan AR ( in “Babak”, “Sherur”, “ Kengerli” regions).From the other selected three species, S.verticulata is come across in the all regions of Azerbaijan, S.tesquicola is in the Nakhchivan plain and “Goygol” region in the north of LC,and S.sclareais in the east of LC range ( in the “Shamkir” and “Gadabay” regions) and in the Nakhchivan highlands.

Alteration of Neutrophil Reactive Oxygen Species Production by Extracts of Devil's Claw (Harpagophytum).

Harpagophytum, Devil's Claw, is a genus of tuberiferous xerophytic plants native to southern Africa. Some of the taxa are appreciated for their medicinal effects and have been traditionally used to relieve symptoms of inflammation. The objectives of this pilot study were to investigate the antioxidant capacity and the content of total phenols, verbascoside, isoverbascoside, and selected iridoids, as well as to investigate the capacity of various Harpagophytum taxa in suppressing respiratory burst in terms of reactive oxygen species produced by human neutrophils challenged with phorbol myristate acetate (PMA), opsonised Staphylococcus aureus, and Fusobacterium nucleatum. Harpagophytum plants were classified into different taxa according to morphology, and DNA analysis was used to confirm the classification. A putative new variety of H. procumbens showed the highest degree of antioxidative capacity. Using PMA, three Harpagophytum taxa showed anti-inflammatory effects with regard to the PBS control. A putative hybrid between H. procumbens and H. zeyheri in contrast showed proinflammatory effect on the response of neutrophils to F. nucleatum in comparison with treatment with vehicle control. Harpagophytum taxa were biochemically very variable and the response in suppressing respiratory burst differed. Further studies with larger number of subjects are needed to corroborate anti-inflammatory effects of different taxa of Harpagophytum.

Quantification of Heavy Metals in the &lt;I&gt;Aloe vera&lt;/I&gt; L. Samples Available in the Market

The plant Aloe vera L. (Synonym: Aloe barbadensis Mill.) has been use for decades for beauty, health as well as medicinal purposes . In dermatology also it is widely being used. As many other herbs this succulent xerophytic plant also can absorb heavy metals through roots. The fresh leaves are nowadays in high demand as rejuvenating agent in cancer patients which necessitates quality assurance. In market, bundles of it are available for sale collected from various places. The presence of any toxic elements in it may lead to serious health hazards, if above permissible levels. In the present study, market samples of A. vera were collected from local markets and the heavy metal content analysis was carried out using ICP-AES (Inductively coupled plasma) method to assess the heavy metal load of A. vera samples. The results revealed that out of 10 samples analyzed, one proved to have lead content above WHO permissible limit, where as all other samples were having below permissible levels of heavy metals.

Species composition and phytosociology of xerophytic plant communities after extreme rainfall in South Peru

We present a phytosociological overview of the arid and semi-arid montane vegetation of the province of Arequipa in southern Peru. The xerophytic vegetation was studied after extreme rainfall had promoted exceptionally lush vegetation and a high aboveground floristic diversity. We used TWINSPAN for classification and Detrended Correspondence Analysis for gradient analysis of our releves. PC-ORD was used to show the hierarchical similarity structure of the syntaxa, and to compare them with related communities in Peru and surrounding countries from literature. We present a synoptic table, and describe the physiognomy, floristic composition, ecology and spatial distribution of the plant communities. In total, we recorded 187 plant species, including 50 endemics, in 196 phytosociological releves distributed over 2030 km2 at an elevation between 2020 and 3260 m a. s. l. The releves were assigned to three alliances in the class Opuntietea sphaericae. The vegetation consists mainly of native species of trees, shrubs, grasses, succulents, annual herbs, and ferns. The most diverse families were Asteraceae, Cactaceae, Solanaceae, Malvaceae, Boraginaceae, Fabaceae, Poaceae, Amaranthaceae and Pteridaceae. Within the class Opuntietea sphaericae, three alliances have been distinguished of which two are new. The Ambrosio artemisioidis-Weberbauerocerion weberbaueri comprising six associations was recorded on barren hillsides between 2000 and 2900 m a. s. l. in the Arequipa city boundary zones. The Corryocaction brevistyli defines xerophytic scrub between 2700 and 3200 m a. s. l. in semi-dry regions bordering the puna grasslands. It contains the Balbisio weberbaueri-Ambrosietum artemisioidis and the Aloysio spathulatae-Corryocactetum brevistyli, all in need of further investigation as they lack diagnostic species. A unit clearly distinguished by Weberbauerocereus rauhii and Neoraimondia arequipensis is here described as a new alliance, Neoraimondio arequipensis-Weberbauerocerion rauhii. It grows in inter-Andean valleys in dry regions (1100- 2200 m a. s. l.), with abundant cacti accompanied by few xerophytes.

De novo transcriptome sequencing and comprehensive analysis of the drought-responsive genes in the desert plant Cynanchum komarovii.

BackgroundCynanchum komarovii Al Iljinski is a xerophytic plant species widely distributing in the severely adverse environment of the deserts in northwest China. At present, the detailed transcriptomic and genomic data for C. komarovii are still insufficient in public databases.ResultsTo investigate changes of drought-responsive genes and explore the mechanisms of drought tolerance in C. komarovii, approximately 27.5 GB sequencing data were obtained using Illumina sequencing technology. After de novo assembly 148,715 unigenes were generated with an average length of 604 bp. Among these unigenes, 85,106 were annotated with gene descriptions, conserved domains, gene ontology terms, and metabolic pathways. The results showed that a great number of unigenes were significantly affected by drought stress. We identified 3134 unigenes as reliable differentially expressed genes (DEGs). During drought stress, the regulatory genes were involved in signaling transduction pathways and in controlling the expression of functional genes. Moreover, C. komarovii activated many functional genes that directly protected against stress and improved tolerance to adapt drought condition. Importantly, the DEGs were involved in biosynthesis, export, and regulation of plant cuticle, suggesting that plant cuticle may play a vital role in response to drought stress and the accumulation of cuticle may allow C. komarovii to improve the tolerance to drought stress.ConclusionThis is the first large-scale reference sequence data of C. komarovii, which enlarge the genomic resources of this species. Our comprehensive transcriptome analysis will provide a valuable resource for further investigation into the molecular adaptation of desert plants under drought condition and facilitate the exploration of drought-tolerant candidate genes.Electronic supplementary materialThe online version of this article (doi:10.1186/s12864-015-1873-x) contains supplementary material, which is available to authorized users.

Biological rehabilitation in the degraded land, a case study of Shariingol Soum of Selenge Aimag in Mongolia

Land is degraded and abandoned by intensive usages from mining and agriculture activities in the northern part of Mongolia. Especially agriculture land usage without rotation is one of the reasons of soil fertility loss. Land degradation is not only becoming an ecological degradation, but also decrease of economic benefits.We have conducted a survey on the planting perennial in the abandoned and degraded land. Planting perennials in the degraded lands is considering a one of the important technologies for plant regeneration (Institute of Geoecology, MAS. 2002). Lands are traditionally used for pasture and animal husbandry, but in recent decades multiple land use has increased rapidly in Mongolia. Especially, the mining activities have been implemented rapidly.From the result, we can see that, the wintering of Medicago falcata L is 70-76 percent and yield is 12-16.4 centner/ha in the abandoned land, and 80-85 percent for wintering and yield is 2-3.5 centner/ha in the degraded land from mining activities. Due to planting perennial, xerophyte plants increased by 12 percent and mesophyte plants increased by 45 percent in the abandoned land. In contrast, mesophyte plants decreased by 2 percent, and xerophyte plants decreased by 8 percent in the degraded land from mining activities.Journal of agricultural sciences №15 (02): 106-112, 2015

Palynomorph assemblages and paleoclimate records from the Zhuanchengzi Bed of the Yixian Formation, western Liaoning Province, China

We collected, processed, identified, and analyzed the spores and pollen samples from the Zhuanchengzi Bed of the Yixian Formation in the Yingwoshan area of western Liaoning. As a result, we confirm a palynomorph assemblage of Cicatricosisporites-Protoconiferus. The pollen was primarily from gymnosperms, dominated especially by conifer pollen. Pteridophyte spores were less common and some questionable angiosperm pollen occurred occasionally. The age of the palynomorph assemblage is dated as the late Valanginian or Hauterivian-Barremian stage, the Early Cretaceous. The study applies the concept of Palynological Vegetation based on palynological spectra and the paleoecological characteristics of palynological taxa for the first time. Palynological vegetation type, climatic zone type, and humidity type are divided quantitatively for the Zhuanchengzi Bed in the Yixian Formation of western Liaoning. We then obtained the evolutionary trends. The results showed that the overall climate was warm and humid during the deposition period of the Zhuanchengzi Bed in the Yixian Formation. Palynological vegetation types are various and include coniferous forest, deciduous broadleaf forest, evergreen broad-leaved forest, grass, and shrubs. The local temperature changed from warm to much warmer and from a semi-humid to humid climate. Palynological vegetation types are always dominated by coniferous forest. The coexistence of deciduous broad-leaved forest, evergreen broad-leaved forest, shrubs, grass, and some xerophytic plants indicates vertical zonation and seasonal climate change The vertical vegetation types and the warm humid climate may imply a large geomorphological contrast in the Yixian Formation of western Liaoning.