Woody encroachment over 70 years in South African savannahs: overgrazing, global change or extinction aftershock?
نویسندگان
چکیده
منابع مشابه
Effects of anabolic and catabolic nutrients on woody plant encroachment after long-term experimental fertilization in a South African savanna
The causes of the worldwide problem of encroachment of woody plants into grassy vegetation are elusive. The effects of soil nutrients on competition between herbaceous and woody plants in various landscapes are particularly poorly understood. A long-term experiment of 60 plots in a South African savanna, comprising annual applications of ammonium sulphate (146-1166 kg ha-1 yr-1) and superphosph...
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Processes that control the hydrological balance in eastern South Africa on orbital to millennial timescales remain poorly understood because proxy records documenting its variability at high resolution are scarce. In this work, we present a detailed 270,000 year-long record of terrestrial climate variability in the KwaZulu-Natal province based on elemental ratios of Fe/K from the southwest Indi...
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We discuss three interlinked issues: the natural pace of environmental change and adaptation, the likelihood that a population will adapt to a potentially lethal change, and adaptation to elevated CO2, the prime mover of global change. Environmental variability is governed by power laws showing that ln difference in conditions increases with ln elapsed time at a rate of 0.3-0.4. This leads to s...
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A large fraction of the world grasslands and savannas are undergoing a rapid shift from herbaceous to woody-plant dominance. This land-cover change is expected to lead to a loss in livestock production (LP), but the impacts of woody-plant encroachment on this crucial ecosystem service have not been assessed. We evaluate how tree cover (TC) has affected LP at large spatial scales in rangelands o...
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ژورنال
عنوان ژورنال: Philosophical Transactions of the Royal Society B: Biological Sciences
سال: 2016
ISSN: 0962-8436,1471-2970
DOI: 10.1098/rstb.2015.0437