Soil and vegetation seasonal changes in the grazing Andean Mountain grasslands     

MU?OZ María ángeles  FAZ ángel 《山地科学学报》2014,11(5):1123-1137

Andean grasslands ecosystems are fragile environments with rigorous climatologic conditions and low and variable food for the grazing. The Apolobamba area is located in the Bolivian Andean Mountains. Its high grasslands provide a natural habitat for wild and domestic camelids such as vicuna（Vicugna vicugna） and alpaca（Lama pacos）. The botanical diversity plays an essential role in maintaining vital ecosystem functions. The objectives of this research were to determine the seasonal changes in soil properties, to study the vegetation changes during the wet and dry seasons and the influence of soil properties and camelid densities on the vegetation in the Apolobamba grasslands. Four zones with different vicuna populations were selected to be studied. The following soil parameters were determined： total organic carbon, total nitrogen, available phosphorous, cation exchange capacity, exchangeable cations, pH and texture. The vegetation season changes were studied through botanical identification, above-ground biomass, plant cover and species richness. Results showed that some soil properties such as C/N ratio, CEC, silt and clay percentages kept stable against the seasonal changes. Generally, soil nutrients were relatively higher during the dry season in the surface and subsurface. The results did not point out the predominant vegetation growth during the wet season. The seasonal vegetation growth depended on each species. Thegood soil fertility corresponded to the highest plant cover. Soil fertility presented no influence on the above-ground biomass of the collected species. The negative influence of camelid grazing on soil properties could not be assessed. However, overgrazing could affect some plant species. Therefore, protection is needed in order to preserve the biodiversity in the Andean mountain grasslands.  相似文献   

Mushroom production as an alternative for rural development in a forested mountainous area     

José A. BONET  José R. GONZáLEZ-OLABARRIA  Juan MARTíNEZ DE ARAGóN 《山地科学学报》2014,11(2):535-543

Wild mushrooms are recognized as important non-wood forest products in mountainous ecosystems, but their real potential for generating rural economies has not been fully evaluated due to the difficulties in obtaining reliable productivity data, minimizing their true potential as contributor to rural economies. Mushroom yield models based on large data series from Pinus forest ecosystems in the region of Catalonia(Spain), combined with data from the Spanish National Forest Inventory allow us to estimate the potential mushroom productivity by forest ecosystems. The results of 24,500 tons/yr of mushrooms of which 16,300 tons are classified as edible and 7,900 tons are commonly marketed demonstrate the importance of mushroom productions in Catalonian pine forests, mostly located in mountainous areas where the development of agricultural activities is limited. Economic mushroom value is estimated at 48 million € for the edible mushroom and 32 million € for those corresponding to marketable yields, confirming the potential of this non-wood forest product. These production results and corresponding economic values provide a basis for the incorporation of wild mushrooms as significant non-wood forest products in the development of forest policies in mountainous areas.  相似文献   

Modeling heavy metal concentration distributions in estuarine waters: an application to Suances Estuary (Northern Spain)     

María Luisa Sámano  Andrés García  José Antonio Revilla  César Álvarez 《Environmental Earth Sciences》2014,72(8):2931-2945

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Dispersion modeling of air pollutants in the atmosphere: a review     

Ádám Leelőssy  Ferenc Molnár Jr.  Ferenc Izsák  Ágnes Havasi  István Lagzi  Róbert Mészáros 《Central European Journal of Geosciences》2014,6(3):257-278

Modeling of dispersion of air pollutants in the atmosphere is one of the most important and challenging scientific problems. There are several natural and anthropogenic events where passive or chemically active compounds are emitted into the atmosphere. The effect of these chemical species can have serious impacts on our environment and human health. Modeling the dispersion of air pollutants can predict this effect. Therefore, development of various model strategies is a key element for the governmental and scientific communities. We provide here a brief review on the mathematical modeling of the dispersion of air pollutants in the atmosphere. We discuss the advantages and drawbacks of several model tools and strategies, namely Gaussian, Lagrangian, Eulerian and CFD models. We especially focus on several recent advances in this multidisciplinary research field, like parallel computing using graphical processing units, or adaptive mesh refinement.  相似文献   

Pliocene and late Pleistocene (MIS 5e) decapod crustaceans from Santa Maria Island (Azores Archipelago: Central Atlantic): systematics,palaeoecology and palaeobiogeography     

Matúš Hyžný  Carlos S. Melo  Ricardo S. Ramalho  Ricardo Cordeiro  Patrícia Madeira  Lara Baptista  A. Cristina Rebelo  Cynthia Gómez  Alfred Uchman  Markes E. Johnson  Björn Berning  Sérgio P. Ávila 《第四纪科学杂志》2021,36(1):91-109

The presence of decapod crustaceans in the Pliocene and Pleistocene (MIS 5e) fossil record of Santa Maria Island (Azores Archipelago) is herein reviewed. Our study raises the number of fossil decapods from this island from one species to 10 taxa (three for the Pliocene and seven for the Last Interglacial). Four of these 10 taxa are reported for the first time in the fossil record, worldwide. A new species of a mud shrimp is also described (Upogebia azorensis n. sp.). Our study suggests that the Plio–Pleistocene decapod assemblages of the Azores did not differ significantly from modern ones, being dominated by species that are today widespread across the Webbnesia ecoregion, the Mediterranean Sea, and the eastern Atlantic shores, including the Azores. As far as can be judged from the limited fossil record, apparently no tropical crab species with a Cabo Verdean/Senegalese provenance reached the Azores during windows of opportunity associated with Glacial Termination 2 or with the initial setting of the Last Interglacial period. This contribution increases the total number of marine taxa reported for the Pliocene and Pleistocene outcrops of Santa Maria Island to 218 and 155, respectively, highlighting the scientific relevance of its palaeontological heritage.  相似文献   

A 10Be production‐rate calibration for the Arctic     

NICOLÁs E. YOUNG  JOERG M. SCHAEFER  JASON P. BRINER  BRENT M. GOEHRING 《第四纪科学杂志》2013,28(5):515-526

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Modeling spatial landslide susceptibility in volcanic terrains through continuous neighborhood spatial analysis and multiple logistic regression in La Ciénega watershed,Nevado de Toluca,Mexico     

Castro-Miguel  Rutilio  Legorreta-Paulín  Gabriel  Bonifaz-Alfonzo  Roberto  Aceves-Quesada  José Fernando  Castillo-Santiago  Miguel Ángel 《Natural Hazards》2022,113(1):767-788

Natural Hazards - Little study has been done on the effect of the pixel neighborhood information when modeling landslide susceptibility using multiple logistic regression (MLR). The present...  相似文献   

Sunspots During the Maunder Minimum from Machina Coelestis by Hevelius     

V. M. S. Carrasco  J. Villalba Álvarez  J. M. Vaquero 《Solar physics》2015,290(10):2719-2732

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The Influence of the Electron κ-Distribution in the Solar Corona on the Fe VIII – Fe XV Line Intensities     

Elena DzifčÁKOVÁ 《Solar physics》2006,234(2):243-256

Changes in the excitation equilibrium of Feviii – Fe xv in the solar corona due to the electron non-thermal κ-distribution are studied. The shape of the distribution affects the electron excitation rate and thus the relative intensities of the spectral lines. Since the shape of the electron distribution function influences also the ionization equilibrium of Fe, both effects change the final intensities of the lines. Possibilities for diagnostics of the shape of the electron distribution in the solar corona are discussed. Synthetic spectrum of Fe for T = 1.58× 10⁶ K and n_e = 10⁸ cm⁻³ is shown together with the synthetic spectra computed with DEM for the quiet Sun.  相似文献   

INDUSTRIAL HERITAGE AND PLACE IDENTITY IN SPAIN: FROM MONUMENTS TO LANDSCAPES*     

PAZ BENITO DEL POZO  PABLO ALONSO GONZÁLEZ 《Geographical review》2012,102(4):446-464

In Spain, the birth of interest in the nation's industrial heritage dates from the 1980s and occurred alongside the process of deindustrialization. Policies concerning derelict industrial sites have shifted gradually from destruction to preservation, rehabilitation, and enhancement, and industrial heritage enhancement projects are now widespread in the country. However, a clear mismatching has arisen between institutional and academic initiatives and local communities, which exhibit widespread disinterest in or even rejection of industrial remains. This problematic situation can be related to the utilization of industrial heritage as an economic resource without paying much attention to its connections with memory and identity. Also, the mismatching is due to a positivist approach to industrial heritage whereby the monument and the museum are prioritized. We argue that projects which consider industrial remains as part of cultural landscapes might shorten the gap between the institutional and economic side of industrial heritage and its identity‐building and popular facets.  相似文献