Soil Modifiers (Ca-Zeolite and Gypsum) as Ecosystem Engineers in Soils of Humid and Semi-arid Tropical Climates

The present study demonstrates the effects of abiotic variables on phytoplankton in two different tropical climates. Samples were taken from tropical reservoirs, including six from a tropical climate (As) and five from a semi-arid climate (BSh). Phytoplankton samples were identified, biomass was quantified and climatic and physicochemical variables were evaluated. Canonical analyses were performed in order to observe the effects of abiotic variables on phytoplankton. In both As and BSh ecosystems, the effects of the physicochemical variables were significant, but the synergistic effects between variables and climatic conditions were more pronounced in BSh. Micronutrients had a significant role in structuring the phytoplankton community in both As and BSh. In As, Cylindrospermopsis raciborskii occurred in the presence of lower concentrations of zinc and copper, whereas in BSh this species was present in the presence of higher concentrations of zinc. In the As climate, Geitlerinema amphibium, Cyclotella meneghiniana, Planktothrix agardhii and Microcystis aeruginosa were associated with higher sodium concentrations in the water, whereas in the BSh climate these species experienced lower rainfall. The findings of the present study show that climate determines the effects of abiotic variables on the phytoplankton community in both an independent and synergistic manner. In the present study, phytoplankton in tropical and semi-arid reservoirs is mostly regulated by nutrients, the effects of which vary according to climate.

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Testing for consistency in the impacts of a burrowing ecosystem engineer on soil and vegetation characteristics across biomes

Scientific Reports ◽

10.1038/s41598-019-55917-x ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 1

Author(s):

M. A. Louw ◽

N. S. Haussmann ◽

P. C. le Roux

Keyword(s):

Species Composition ◽

Ecosystem Engineer ◽

Environmental Gradients ◽

Plant Cover ◽

Ecosystem Engineers ◽

Conservation Strategies ◽

Annual Rainfall ◽

Mesic Grassland ◽

Vegetation Characteristics ◽

Semi Arid

AbstractThe impacts of ecosystem engineers may be expected to vary along environmental gradients. Due to some resources being more limited in arid than in mesic environments, disturbances created by burrowing mammals are expected to have a greater ameliorating effect in arid environments, with larger differences in microhabitat conditions expected between burrows and undisturbed areas. The aim of this study was to test if the impacts of a medium-sized burrowing mammal, the aardvark, on soil properties (soil temperature, moisture and compaction) and vegetation characteristics (plant cover, species richness and species composition) are consistent across three biomes that differ strongly in annual rainfall. Burrowing affected soil and vegetation attributes, but the direction and magnitude of these biogeomorphological impacts were not consistent across the different biomes. For example, plant species composition was altered by burrowing in the arid scrubland and in the mesic grassland, but not in the semi-arid savannah. Contrary to expectations, the difference in the impacts of burrowing between biomes were not related to rainfall, with burrowing having strong, albeit different, impacts in both the arid scrubland and the mesic grassland, but weaker effects in the semi-arid savannah. It appears, therefore, that the impacts of these biogeomorphic agents may be site-specific and that it may be difficult to predict variation in their biotic and abiotic effects across environmental gradients. As a result, forecasting the impacts of ecosystem engineers under different conditions remains a challenge to management, restoration and conservation strategies related to these types of species.

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A promising new tamarind selection-lakshamana : Linking biodiversity with livelihood

Journal of Horticultural Sciences ◽

10.24154/jhs.2020.v15i02.014 ◽

2020 ◽

Vol 15 (2) ◽

pp. 221-224

Author(s):

C Kanupirya ◽

G Karunakaran ◽

P Singh

Keyword(s):

Rural Poor ◽

Marginal Lands ◽

Widespread Occurrence ◽

Global Challenges ◽

Neglected And Underutilized Species ◽

Horticultural Traits ◽

Underutilized Species ◽

Participatory Breeding ◽

Tropical Climates ◽

Semi Arid

Tamarind is a well-known commodity of Indian cuisine having medicinal and industrial uses. It is a nutritious tree crop of widespread occurrence growing on marginal lands in semi-arid and sub-humid tropical climates of India, making it highly valuable in ensuring food security for rural poor. Given the great potential of this neglected and underutilized species to address global challenges such as hunger, poverty and climate change adaptation, there is a need to revisit research and development priorities in its favor and to develop strategies together with stakeholders to increase its utilization. In the present study, a survey was undertaken in Tumkur district of Karnataka to characterize the variability available in tamarind for pod and tree characters and identify superior trees using horticultural traits. A farmer’s tamarind selection “Lakshamana” emerged from participatory breeding having significantly better traits compared to local tamarind.

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Drought-induced starvation of aardvarks in the Kalahari: an indirect effect of climate change

Biology Letters ◽

10.1098/rsbl.2017.0301 ◽

2017 ◽

Vol 13 (7) ◽

pp. 20170301 ◽

Cited By ~ 9

Author(s):

Benjamin Rey ◽

Andrea Fuller ◽

Duncan Mitchell ◽

Leith C. R. Meyer ◽

Robyn S. Hetem

Keyword(s):

Climate Change ◽

Body Temperature ◽

Indirect Effect ◽

Indirect Effects ◽

Activity Patterns ◽

Ecosystem Engineers ◽

Direct And Indirect Effects ◽

Physiological Plasticity ◽

Temperature Records ◽

Semi Arid

Aardvarks ( Orycteropus afer ) are elusive burrowing mammals, predominantly nocturnal and distributed widely throughout Africa except for arid deserts. Their survival may be threatened by climate change via direct and indirect effects of increasing heat and aridity. To measure their current physiological plasticity, we implanted biologgers into six adult aardvarks resident in the semi-arid Kalahari. Following a particularly dry and hot summer, five of the study aardvarks and 11 other aardvarks at the study site died. Body temperature records revealed homeothermy (35.4–37.2°C) initially, but heterothermy increased progressively through the summer, with declining troughs in the nychthemeral rhythm of body temperature reaching as low as 25°C before death, likely due to starvation. Activity patterns shifted from the normal nocturnal to a diurnal mode. Our results do not bode well for the future of aardvarks facing climate change. Extirpation of aardvarks, which play a key role as ecosystem engineers, may disrupt stability of African ecosystems.

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Interactive Effects of Three Ecosystem Engineers on Infiltration in a Semi-Arid Mediterranean Grassland

Ecosystems ◽

10.1007/s10021-010-9335-4 ◽

2010 ◽

Vol 13 (4) ◽

pp. 499-510 ◽

Cited By ~ 95

Author(s):

David J. Eldridge ◽

Matthew A. Bowker ◽

Fernando T. Maestre ◽

Patricia Alonso ◽

Rebecca L. Mau ◽

...

Keyword(s):

Ecosystem Engineers ◽

Interactive Effects ◽

Semi Arid

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Climate Variability, Climate Change and Social Vulnerability in the Semi-arid Tropics

10.1017/cbo9780511608308 ◽

1996 ◽

Cited By ~ 42

Keyword(s):

Climate Change ◽

Climate Variability ◽

Social Vulnerability ◽

Semi Arid

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Ferrihydrite dissolution at the root zone of crops under semi-arid condition controls the plant uptake of uranium and arsenic

10.1021/scimeetings.0c03694 ◽

2020 ◽

Author(s):

Arindam Malakar ◽

Michael Kaiser ◽

Daniel D. Snow ◽

Harkamal Walia ◽

Chittaranjan Ray

Keyword(s):

Plant Uptake ◽

Root Zone ◽

Arid Condition ◽

Semi Arid

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Life strategies in a semi-arid grassland community — mechanisms of dispersal and reproduction within Lapiedro martinezii-Stipetum tenacissimae (Southeastern Spain)

Feddes Repertorium ◽

10.1002/fedr.4921100310 ◽

1999 ◽

Vol 110 (3-4) ◽

pp. 265-285 ◽

Cited By ~ 1

Author(s):

I. Hensen

Keyword(s):

Life Strategies ◽

Grassland Community ◽

Southeastern Spain ◽

Semi Arid

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THE CLASSIFICATION OF LAND ACCORDING TO THE DEGREE OF RABBIT INFESTATION IN CENTRAL OTAGO

Proceedings of the New Zealand Grassland Association ◽

10.33584/jnzg.1987.48.1792 ◽

1987 ◽

pp. 65-70

Author(s):

I.G.C. Kerr ◽

J.M. Williams ◽

W.D. Ross ◽

J.M. Pollard

Keyword(s):

Carrying Capacity ◽

Mediterranean Climate ◽

Natural Habitat ◽

Public Funding ◽

Soil Survey ◽

European Rabbit ◽

Cultural Modification ◽

Classification Information ◽

Semi Arid

The European rabbit (Oryctolagus cuniculus) introduced into New Zealand in the 183Os, has consistently flourished in Central Otago, the upper Waitaki, and inland Marlborough, all areas of mediterranean climate. It has proved difficult to manage in these habitats. The 'rabbit problem' is largely confined to 105,000 ha of low producing land mostly in semi arid areas of Central Otago. No field scale modifications of the natural habitat have been successful in limiting rabbit numbers. The costs of control exceed the revenue from the land and continued public funding for control operations appears necessary. A system for classifying land according to the degree of rabbit proneness is described. Soil survey and land classification information for Central Otago is related to the distribution and density of rabbits. This intormation can be used as a basis for defining rabbit carrying capacity and consequent land use constraints and management needs. It is concluded that the natural rabbit carrying capacity of land can be defined by reference to soil survey information and cultural modification to the natural vegetation. Classification of land according to rabbit proneness is proposed as a means of identifying the need for, and allocation of, public funding tor rabbit management. Keywords: Rabbit habitat, rabbit proneness, use of rabbit prone land.

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