Paleovegetational Reconstruction and Implications on Formation of Oil Shale and Coal in the Lower Cretaceous Laoheishan Basin (NE China): Evidence from Palynology and Terpenoid Biomarkers

In some cases, the oil shale deposited in shallow lakes may be genetically associated with the coal-bearing successions. Although paleovegetation is an important controlling factor for the formation of oil shale- and coal-bearing successions, few studies have focused on their joint characterization. In this study, a total of twenty-one oil shale and coal samples were collected from the upper member of the Lower Cretaceous Muling Formation (K1ml2) in the Laoheishan Basin, and investigated for their bulk geochemical, maceral, palynological, and terpenoid biomarker characteristics, in order to reconstruct the paleovegetation and reveal its influence on the formation of oil shale and coal. The K1ml2 is subdivided into lower, middle, and upper units. The studied oil shale samples from the lower and upper units display a high ash yield (Ad), low total organic carbon (TOC) and sulfur (S) contents, and limited hydrocarbon generation potential. The studied coal samples from the middle unit are characterized by low Ad, and high TOC and low S values, and show significant hydrocarbon generation potential. The paleovegetation during the formation of the lower unit was dominated by mire vegetation, such as shrubs (e.g., Lygodiaceae, Schizaeaceae), tree ferns (e.g., Dicksoniaceae/Cyatheaceae), and coniferous trees (e.g., Podocarpaceae). In the middle unit interval, the paleovegetation was represented by highland vegetation (Pinaceae and Araucariaceae) and peat-forming coniferous plants (e.g., Podocarpaceae, Cupressaceae/Taxodiaceae). Various vegetation, such as herbs (e.g., Osmundaceae), shrubs (e.g., Schizaeaceae), and coniferous trees (e.g., Podocarpaceae) was prosperous during the upper unit interval. Coniferous trees could provide abundant hydrogen-rich materials (e.g., resins) to the mire/lake, which may elevate the hydrogen content in peat/lake sediments, and finally result in higher hydrocarbon generation potential in the coal than in the oil shale. Therefore, the influence of paleovegetation on the formation of oil shale and coal should be fully considered when studying oil shale- and coal-bearing successions. The results also provide guidance for further exploration studies on oil shale and coal in northeast China.

Communities of Festuca komarovii – endemic of cryo-arid Pleistocene vegetation of the Eastern Sayan

The identity of the highland vegetation of the eastern part of the ridge East Sayan is due to the history of the formation of flora and vegetation in the late Pleistocene, as well as to the features of underlying rocks, mainly represented by limestones. As a result, endemic plant species and communities formed on these ancient alignment surfaces. One of these species is Festuca komarovii Krivot. (Komarov fescue). The relictness of Festuca komarovii is confirmed by the systematic position of the species in the generic complex; it belongs to the distinctive section Leocopoa (Griseb.) Krivot. The section combines only three species – Festuca sibirica, F. hubsugulica, F. komarovii, of which the last two are endemic of the Hangai-Sayan center. The Komarov fescue in the modern vegetation of the East Sayan shows itself as a coenogen and indicator of paleocryogenic landscapes. The research results showed a high coenotic role of this fescue in the vegetation of the studied territory, in particular the syntaxa of the cryophyte-steppe florocenotype (unions Kobresion myosuroidis Mirkin et al. 1983 em. Hilbig 2000 and Potentillo niveae–Caricion pediformisТеlyatnikov 2011). We also described the new association Ptilagrosto mongholicae–Festucetum komarovii Namzalov ass. hoc loco, floristically and coenotically related to the associations of the union Dryadion oxyodontae Zhitlukhina et Onishchenko ex Chytrý et al. 1993, which belongs to the class Carici rupestris–Kobresietea bellardii Ohba 1974. However, one important feature should be noted that the Komarov fescue in communities of associations of tundra and subalpine forest vegetation is noted in a small abundance as an accompanying species. To some extent, this confirms the initial coenogenetic proximity of Festuca komarovii to grass ecosystems – cryophytic stepoids of the periglacial Pleistocene complex.

The Subnival Vegetation of Moquegua, South Peru: Chasmophytes, Grasslands and Cushion Communities

The present work is a phytosociological synthesis and syntaxonomic overview of the vegetation of the highest subnival parts (superpuna) of the open alpine vegetation of the high plateaus (puna) of the Andes of Moquegua, South West Peru, as related to the main environmental gradients. Using TWINSPAN and DCA ordination analysis, 153 phytosociological relevés were analyzed. For each association, subassociation and community, the syntaxonomy, floristic diversity and relation with environmental variables are described. The syntaxonomy and synecology of superpuna vegetation was studied in 19 localities at an altitude of 4450–4800 m. The study area has a pluviseasonal climate with yearly rainfall (December-April). Four main highland vegetation types were distinguished: 1. slope and scree chasmophyte vegetation composed of shrubs, cushions, ground rosettes and grasses, 2. grasslands (grazed and ungrazed) characterized by great species richness in shrubs, cushions, ground rosettes, grasses and herbs, 3. vegetation of plateaus with cushions, shrubs, ground rosettes, herbs and grasses and 4. nitrophilous vegetation with high cover and low species richness. Within the vegetation of the orotropical and cryorotropical bioclimatic belts three phytosociological classes can be distinguished: Argyrochosmetea niveae (chasmophytic vegetation), Calamagrostietea vicunarum (grasslands with cushions), Anthochloo lepidulae-Dielsiochloetea floribundae (highland slopes and plateaus) and a nitrophylous community. One new association from rock and scree slopes was described within the Saxifragion magellanicae (Argyrochosmetea niveae). Within the Calamagrostion minimae, which comprises grasslands with cushions and mat-forming plants, one new association with two subassociations could be distinguished. Within the grassland and cushion associations of the Azorello-Festucion (Calamagrostietea vicunarum), three new associations were described, comprising nine subassociations. In the Anthochloo-Dielsiochloetalia one new and one previously described association and one community are distinguished. In addition, the nitrophilous community of Tarasa nototrichoides and Urtica flabellata has been described. In total the vegetation comprised 172 vascular species belonging to 32 families. Our study provides the first syntaxonomic revision of chasmophytes, cushion associations and high-altitude grasslands in the Andes of North Moquegua. The proposed syntaxonomic scheme contains the associations distributed under similar habitat conditions throughout the Southern Andes of Peru, but also the associations reflecting the local floristic and environmental patterns. The subnival vegetation of Moquegua hosts some rare endangered and/or protected plant species.

Approach of Soil and Water Conservation on Desilting Highland in Typical Irrigation Area from the Lower Yellow River

Exampled by Weishan irrigated area, the largest irrigation area in the lower basin of Yellow River, this study summarizes the experience of erosion controlling on desilting highland for years and proposes comprehensive control modes including water diversion irrigation management. After taking the engineering measures such as land leveling, soil mulching and land planishing and the vegetation measures such as slope protection by highland vegetation and shelterbelt network, the desilting highland in Weishan irrigation area was overall controlled, soil erosion and ecological environment deterioration have been restrained effectively.

The roles of history and habitat area in the distribution and composition of avian species assemblages in the highlands of Costa Rica

Bird species assemblages in isolated Neotropical highland mountains have been moulded by the drastic climatic changes that occurred in late Pleistocene. Palynological evidence indicates that after the Pleistocene the highlands of Costa Rica and western Panama became isolated as climate turned gradually more tropical and highland vegetation retreated to the upper elevations of high mountains, forming highland islands. We surveyed birds at 10 representative sites throughout the Costa Rican highlands in order to determine the species composition of highland endemic assemblages. The area of available highland habitat explains 77% of the variance in species richness of the 36 highland endemics across highland islands, and the composition of these species assemblages have a nested distribution, rather than being independent sets of species on each island. The observed nested pattern is more consistent with a differential extinction model of species assemblages, and less likely to be explained by differential migration. We conclude that the reduction of highland vegetation and the avifauna associated with it, and its subsequent confinement to the summit of high mountains, is a possible explanation for the current distribution of highland endemic species in Costa Rican highland islands.

Arbuscular mycorrhizal colonization and growth of Eremanthus incanus Less. in a highland field

This paper focuses on Eremanthus incanus Less. (Asteraceae), a common species of highland regions in Brazil. The effect of arbuscular mycorrhizal (AM) inoculation on plant growth (height and diameter) was evaluated. Roots were examined from individuals randomly selected from undisturbed areas of highland vegetation and from an experimental restored site. Results showed that E. incanus presented high AM colonization both in restored and undisturbed sites. Moreover, AM colonization was significantly higher in the inoculated treatment than in the non-inoculated one. The species presented Arum-type colonization and frequent production of vesicles, especially in the restored site. Arbuscular mycorrhizal inoculation stimulated plant growth (height and diameter). Ten AM fungi (AMF) taxa were found in the studied rooting zones: Acaulospora spinosa, A. elegans, A. foveata, Acaulospora sp., Gigaspora margarita, Glomus sp., Dentiscutata biornata, D. cerradensis, Dentiscutata sp. and Racocetra verrucosa. These results revealed that AMF is a common and important component in highland vegetation in Brazil, and should be included in future restoration programs.

The Invasion of Highlands in Galá'pagos by the Red Quinine-tree Cinchona succirubra

The alien tree species Cinchona succirubra, the Red Quinine-tree (Rubiaceae), was introduced to the Galápagos Islands, Ecuador, in 1946, for purposes of cultivation, but causes much concern as, by 1987, it was found to cover about 4,000 hectares in the highlands of Santa Cruz Island, changing the original, largely endemic, vegetation. Some limited herbicide trials have been made by the Galápagos National Park Service, but a really successful method of controlling this pest still remains to be found.The removal of Cinchona plants from a 1000-ha Intensive Control Area (ICA) within the Galápagos National Park has been successful to date. However, large stands of the tree exist in the adjacent agricultural area of Santa Cruz Island, as well as elsewhere in the National Park. With the maturation of these stands, an increased input of Cinchona succirubra seeds to the ICA can be anticipated.Strengthened use of manual, chemical, and biological, control measures are therefore recommended on a shortterm basis, in order to conserve the unique highland vegetation of Santa Cruz Island, Galápagos.