نتایج جستجو برای: drylands

تعداد نتایج: 912  

2018
Niv DeMalach Hugo Saiz Eli Zaady Fernando T. Maestre

Species accumulation curves (SAC), i.e. the relationship between species richness and the number of sampling units in a given community, can be used to describe diversity patterns while accounting for the well-known scale-dependence of species richness. Despite their value, the functional form and the parameters of SAC, as well as their determinants, have barely been investigated in plant commu...

Journal: :Environmental management 2004
Rattan Lal

Drylands occupy 6.15 billion hectares (Bha) or 47.2% of the world's land area. Of this, 3.5 to 4.0 Bha (57%-65%) are either desertified or prone to desertification. Despite the low soil organic carbon (SOC) concentration, total SOC pool of soils of the drylands is 241 Pg (1 Pg = petagram = 10(15)g = 1 billion metric ton) or 15.5% of the world's total of 1550 Pg to 1-meter depth. Desertification...

Journal: :Proceedings of the National Academy of Sciences of the United States of America 2015
Fernando T Maestre Manuel Delgado-Baquerizo Thomas C Jeffries David J Eldridge Victoria Ochoa Beatriz Gozalo José Luis Quero Miguel García-Gómez Antonio Gallardo Werner Ulrich Matthew A Bowker Tulio Arredondo Claudia Barraza-Zepeda Donaldo Bran Adriana Florentino Juan Gaitán Julio R Gutiérrez Elisabeth Huber-Sannwald Mohammad Jankju Rebecca L Mau Maria Miriti Kamal Naseri Abelardo Ospina Ilan Stavi Deli Wang Natasha N Woods Xia Yuan Eli Zaady Brajesh K Singh

Soil bacteria and fungi play key roles in the functioning of terrestrial ecosystems, yet our understanding of their responses to climate change lags significantly behind that of other organisms. This gap in our understanding is particularly true for drylands, which occupy ∼41% of Earth´s surface, because no global, systematic assessments of the joint diversity of soil bacteria and fungi have be...

Journal: :Applied and environmental microbiology 2015
Blaire Steven Cheryl R Kuske La Verne Gallegos-Graves Sasha C Reed Jayne Belnap

Biological soil crusts (biocrusts) colonize plant interspaces in many drylands and are critical to soil nutrient cycling. Multiple climate change and land use factors have been shown to detrimentally impact biocrusts on a macroscopic (i.e., visual) scale. However, the impact of these perturbations on the bacterial components of the biocrusts remains poorly understood. We employed multiple long-...

2017
Jerome R. Mayaud Nicholas P. Webb

Drylands are characterised by patchy vegetation, erodible surfaces and erosive aeolian processes. Empirical and modelling studies have shown that vegetation elements provide drag on the overlying airflow, thus affecting wind velocity profiles and altering erosive dynamics on desert surfaces. However, these dynamics are significantly complicated by a variety of factors, including turbulence, and...

Journal: :Forests 2023

Arid and semi-arid lands cover more than one-third of the earth’s terrestrial area are typically characterized by rainfall scarcity, higher temperatures evapotranspiration, salinization, nutrient-poor soil, a paucity vegetation [...]

2010
NAOMI PORAT Ashok K. Singhvi

Luminescence dating has truly transformed the science of deserts and drylands and has necessitated a revision of conventional interpretation of sedimentary records and stratigraphic correlations. This contribution discusses key questions in palaeoclimatology of global deserts, the meaning of a luminescence age on desert sand and presents a review of luminescence-dated aeolian sand records from ...

2017
Jianming Wang Tianhan Zhang Liping Li Jingwen Li Yiming Feng Qi Lu

Dryland ecosystems cover more than 30% of the terrestrial area of China, while processes that shape the biogeographic patterns of bacterial and fungal β-diversity have rarely been evaluated synchronously. To compare the biogeographic patterns and its drivers of bacterial and fungal β-diversity, we collected 62 soil samples from a typical dryland region of northwest China. We assessed bacterial ...

2014
Jing Zhang Jianming Niu Alexander Buyantuev Jianguo Wu

Drylands, which occupy more than 40% of the Earth’s land surface, are highly susceptible to degradation. It is important to understand causes, mechanisms, and environmental consequences of dryland ecosystem degradation. Land use policies are known to play a critical role in driving land cover changes, as well as in mitigating land degradation and promoting sustainable development in drylands. W...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید