Cushion Shrubs Encroach Subhumid Rangelands: Fertility Islands in Fragile Soils Along a Grazing Gradient in Patagonia

Abstract PurposeThis work assesses changes in soil and vegetation structure associated with grazing intensity (GI) in subhumid grasslands. We conducted the study in the Subandean district of Patagonia, Argentina. Non-degraded Subandean grass steppes have extremely erodible volcanic soils and are valuable grazing ranges. However, nowadays vast portions exhibit a heterogeneous cover that is mostly of cushions shrubs, with big eroded soil patches.MethodsWe selected four study sites along a GI gradient and one grazed-excluded site. Soils, vegetation cover and patches structure were characterised. We took soil samples beneath grass and shrub patches and their interpatches and in undisturbed spots. ResultsSoils in undisturbed spots had the highest chemical fertility. Soils in grazing areas showed high heterogeneity associated with plant life-form and GI. Results also showed that medium and fine sand particles remobilised from bare soil to vegetated patches. Total nitrogen and organic matter increased in the same direction. Grass cover decreased as GI increases, while shrubs cover and total richness increased, until a collapse at the highest intensity. Relative cover of cushion shrubs and bare soil grow steadily with GI. ConclusionsThe fertility island effect was associated with cushion shrubs. Grazing caused cushion shrub encroachment regardless of its intensity. Notwithstanding this, the same disturbance -grazing- which promoted cushions prevalence also favoured the collapse of fertile islands when reached to maximum intensity. Ecosystem services provision from a range management standpoint decreased. However, the increases in richness under moderate GI could represent an enhancement in system functionality.

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Structure of pond vegetation of a vereda in the Brazilian Cerrado

Rodriguésia ◽

10.1590/s2175-78602011000400002 ◽

2011 ◽

Vol 62 (4) ◽

pp. 721-729 ◽

Cited By ~ 7

Author(s):

Suzana Neves Moreira ◽

Arnildo Pott ◽

Vali Joana Pott ◽

Geraldo Alves Damasceno-Junior

Keyword(s):

Water Depth ◽

Rainy Season ◽

Life Form ◽

Mato Grosso ◽

Relative Cover ◽

Dry Seasons ◽

The Relationship ◽

Measured Water ◽

Mato Grosso Do Sul ◽

New Occurrences

Abstract This is the first report on aquatic macrophytes in ponds of veredas (palm swamps) in the Cerrado (Brazilian savanna). We studied a pond in a vereda in Terenos, Mato Grosso do Sul state, central-western Brazil, during drought and flood periods to assess plant community structure and the relationship between species distribution and water depth. Sampling was carried out in five permanent transects, along which we placed sampling units of 1 m2 quadrats every 5 m. We estimated visually the relative cover of each species, bare ground, dead matter, and exposed water. We also measured water depth. We recorded 77 species of 49 genera and 31 families. The number of species varied between seasons, and in the rainy season the amphibious life form was predominant. The richest families were Poaceae (15 species), Cyperaceae (11), Asteraceae (4) and Lentibulariaceae (4). The richest genera were Rhynchospora (4), Utricularia (4), Eleocharis (4), Aeschynomene (3), Bacopa (3), Ludwigia (3) and Panicum (3). We found six new occurrences for the cerrado. Eleocharis acutangula had the highest relative cover (rainy and dry seasons), followed by Bacopa reflexa (rainy season), Paspalum lenticulare (rainy and dry seasons), Leersia hexandra (rainy and dry seasons), and Sagittaria rhombifolia (rainy season). Some species were distributed mainly at shallower depths, others occurred in deeper water, whereas some species varied greatly in terms of depth. Heliotropium filiforme and Ludwigia nervosa were found only in the dry season. In the rainy season, as expected, the exclusive species were mostly true aquatics.

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Changes in plant life-form, pollination syndrome and breeding system at a regional scale promoted by land use intensity

Diversity and Distributions ◽

10.1111/ddi.12353 ◽

2015 ◽

Vol 21 (11) ◽

pp. 1319-1328 ◽

Cited By ~ 4

Author(s):

Dietmar Moser ◽

Stefan Dullinger ◽

Thomas Mang ◽

Karl Hülber ◽

Franz Essl ◽

...

Keyword(s):

Land Use ◽

Breeding System ◽

Life Form ◽

Regional Scale ◽

Pollination Syndrome ◽

Land Use Intensity ◽

Plant Life ◽

Plant Life Form

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Rangeland condition in relation to environmental variables, grazing intensity and livestock owners' perceptions in semi-arid rangeland in western Iran

The Rangeland Journal ◽

10.1071/rj09022 ◽

2010 ◽

Vol 32 (4) ◽

pp. 367 ◽

Cited By ~ 3

Author(s):

M. Faramarzi ◽

S. Kesting ◽

J. Isselstein ◽

N. Wrage

Keyword(s):

Environmental Variables ◽

Management Practices ◽

Grazing Intensity ◽

Bare Soil ◽

Grazing Pressure ◽

Botanical Composition ◽

Western Iran ◽

Range Condition ◽

Rangeland Condition ◽

Semi Arid

Rangeland condition has often been assessed in relation to either botanical, edaphic, environmental or management factors. In this investigation, we analysed the interaction of soil and topographic variables, management and range condition against the background of a sociological survey of livestock owners in western Iran to better understand the main influencing factors of rangeland quality in the area. In four grazing areas in Kermanshah differing in grazing pressure, environmental variables and livestock owners’ perceptions on range condition, investigations of botanical composition, soil and topographic variables were carried out on 43 main plots. To evaluate range condition, four factors were considered, namely litter frequency, herbage palatability, amount of biomass, and percentage of bare soil. A questionnaire was used to obtain information about management practices, the perception of livestock owners on range condition and suggested solutions to problems in the different grazing areas. The range condition scores showed that the condition of the sites was either fair or poor. Of the soil and topographic factors, only north-facing aspect explained part of the variation in range condition scores. High grazing intensity was associated with poor range condition. To improve the rangeland condition, measures influencing water availability and a reduction of grazing pressure seem to be more relevant in the study area than fertilisation or seeding.

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Biodiversity associations of soil fauna and plants depend on plant life form and are accounted for by rare taxa along an elevational gradient

Soil Biology and Biochemistry ◽

10.1016/j.soilbio.2019.107640 ◽

2020 ◽

Vol 140 ◽

pp. 107640

Author(s):

Guorui Xu ◽

Yuxin Zhang ◽

Shuang Zhang ◽

Keming Ma

Keyword(s):

Life Form ◽

Soil Fauna ◽

Elevational Gradient ◽

Rare Taxa ◽

Plant Life ◽

Plant Life Form

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Potensi Makroalga di Paparan Terumbu Karang Perairan Teluk Lampung

Oseanologi dan Limnologi di Indonesia ◽

10.14203/oldi.2017.v2i1.15 ◽

2017 ◽

Vol 2 (1) ◽

pp. 55 ◽

Cited By ~ 2

Author(s):

Tri Handayani

Keyword(s):

Species Richness ◽

Reef Flat ◽

Life Form ◽

Coastal Ecosystem ◽

Economic Values ◽

Number Of Species ◽

Average Biomass ◽

Study Sites ◽

Surrounding Areas ◽

Base Substrate

<strong>The Potency of Macroalgae in the Reef Flat of Lampung Bay.</strong> Lampung Bay is a strategic area that develops quite rapidly. This condition will put pressure on the coastal ecosystem as the estuary of all activities from surrounding areas. Macroalgae, which is one component of the coastal ecosystem, is also under pressure. Therefore, we need to know the species richness, potency, and macroalgae life characteristics in Lampung Bay waters. The study was conducted in March 2009, in eight locations, namely Piabung, Klagian, Pancur, Limbungan, Puhawang Barat, Puhawang Timur, Puhawang Kecil, and Kalangan. The macroalgae samples were collected by the quadratic transect method. The parameters observed were species, biomass, substrate, and macroalgae life form. A total of 27 macroalgae species were identified consisting of three divisions and 17 genera. Division Chlorophyta, Ochrophyta, and Rhodophyta each consisted of nine species. Nineteen species were macroalgae that have important economic values. The highest number of macroalgae species was found in Pancur, while the lowest was in Kalangan. The genera that dominated the study sites were Halimeda and Caulerpa. The highest average biomass was found in Pancur with 675.5 g/m2, whereas in Kalangan there was no macroalgae observed. The base substrate was dominated by sand. The condition of the base substrate affects the number of species and the nature of macroalgae life. In general, macroalgae resources in the waters of Lampung Bay are not potential to be developed, but Sargassum in Pancur has the potential to be developed as seeds.

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The importance of plant life form on spatial associations along a subtropical coastal dune gradient

Journal of Vegetation Science ◽

10.1111/j.1654-1103.2012.01414.x ◽

2012 ◽

Vol 23 (5) ◽

pp. 952-961 ◽

Cited By ~ 15

Author(s):

Camila T. Castanho ◽

Alexandre A. Oliveira ◽

Paulo Inácio Prado

Keyword(s):

Life Form ◽

Coastal Dune ◽

Spatial Associations ◽

Plant Life ◽

Plant Life Form

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Effect of plant life form on relationship between δD values of leaf wax n-alkanes and altitude along Mount Taibai, China

Organic Geochemistry ◽

10.1016/j.orggeochem.2010.11.005 ◽

2011 ◽

Vol 42 (1) ◽

pp. 100-107 ◽

Cited By ~ 22

Author(s):

Zhang Pu ◽

Liu Weiguo

Keyword(s):

Life Form ◽

Leaf Wax ◽

Plant Life ◽

Plant Life Form

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Remnant seed banks and vegetation as predictors of restored marsh vegetation

Canadian Journal of Botany ◽

10.1139/b98-038 ◽

1998 ◽

Vol 76 (4) ◽

pp. 620-629 ◽

Cited By ~ 22

Author(s):

Stephen C Brown

Keyword(s):

Seed Bank ◽

Wetland Hydrology ◽

Bare Soil ◽

Seed Banks ◽

Forage Crops ◽

Marsh Vegetation ◽

Remnant Vegetation ◽

Species Abundances ◽

Natural Wetlands ◽

Study Sites

Selection of sites for wetland restoration requires analysis of probable success at recreating diverse natural vegetation. We studied the seed banks and the remnant vegetation at restoration sites to determine their degree of similarity to the vegetation that developed following restoration of wetland hydrology. The study sites had been used for forage crops and pasture following long-term drainage. The seed bank was a very poor predictor of plant species abundances following restoration. Similarity between remnant vegetation and restored vegetation was consistently higher than similarity values using seed banks at both restored and natural wetlands. Our results suggest that seed-bank analysis is an inefficient technique for predicting restored vegetation in sites with prolonged disturbance, and that analysis of remnant vegetation on the sites is probably more useful. However, results would probably differ at sites with tile drainage that have limited remnant vegetation or created wetlands with bare soil where seed germination would play a greater role in revegetation. In addition, seed-bank studies are important to determine if aggressive invasive species are present at potential restoration sites.Key words: seed banks, wetlands, restoration, marshes, vegetation.

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