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Grey KA, Foden WB, Midgley GF. Bioclimatic controls of CO2 assimilation near range limits of the CAM succulent tree Aloidendron dichotomum. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:7434-7449. [PMID: 36066187 DOI: 10.1093/jxb/erac343] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Accepted: 08/23/2022] [Indexed: 06/15/2023]
Abstract
Aloidendron dichotomum appears to be undergoing the early stages of a range shift in response to anthropogenic climate change in south-western Africa. High mortality has been recorded in warmer populations, while population expansions have been recorded in cooler poleward parts of its range. This study aimed to determine the key environmental controls on A. dichotomum photosynthesis in areas of population expansion, to inform the potential attribution of directional population expansion to anthropogenic warming. Nocturnal acid accumulation and CO2 assimilation were measured in individuals growing under a range of temperature and watering treatments in a greenhouse experiment. In addition, nocturnal acid accumulation and phosphoenolpyruvate carboxylase activity were quantified in two wild populations at the most southerly and south-easterly range extents. Multiple lines of evidence confirmed that A. dichotomum performs Crassulacean acid metabolism. Total nocturnal acid accumulation was highest at night-time temperatures of ~21.5 °C, regardless of soil water availability, and night-time CO2 assimilation rates increased with leaf temperature, suggesting a causal link to the cool southern range limit. Leaf acidity at the start of the dark period was highly predictive of nocturnal acid accumulation in all individuals, implicating light availability during the day as an important determinant of nocturnal acid accumulation.
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Affiliation(s)
- Kerry-Anne Grey
- Global Change Biology Group, Department of Botany and Zoology, Stellenbosch University, Stellenbosch, South Africa
- School for Climate Studies, Stellenbosch University, Stellenbosch, South Africa
| | - Wendy B Foden
- Global Change Biology Group, Department of Botany and Zoology, Stellenbosch University, Stellenbosch, South Africa
- South African National Parks, Cape Town, South Africa
- Climate Change Specialist Group, Species Survival Commission, International Union for Conservation of Nature, Gland, Switzerland
| | - Guy F Midgley
- Global Change Biology Group, Department of Botany and Zoology, Stellenbosch University, Stellenbosch, South Africa
- School for Climate Studies, Stellenbosch University, Stellenbosch, South Africa
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2
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McLellan RC, Watson DM. The living dead: Demography of Australian sandalwood in Australia's western rangelands. AUSTRAL ECOL 2022. [DOI: 10.1111/aec.13243] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Richard C. McLellan
- Gulbali Institute, School of Animal, Environmental and Veterinary Sciences Charles Sturt University Albury New South Wales Australia
| | - David M. Watson
- Gulbali Institute, School of Animal, Environmental and Veterinary Sciences Charles Sturt University Albury New South Wales Australia
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3
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Martyn TE, Barberán A, Blankinship JC, Miller M, Yang B, Kline A, Gornish ES. Rock structures improve seedling establishment, litter catchment, fungal richness, and soil moisture in the first year after installation. ENVIRONMENTAL MANAGEMENT 2022; 70:134-145. [PMID: 35487980 DOI: 10.1007/s00267-022-01651-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Accepted: 04/11/2022] [Indexed: 06/14/2023]
Abstract
Grasslands are essential natural and agricultural ecosystems that encompass over one-third of global lands. However, land conversion and poor management have caused losses of these systems which contributed to a 10% reduction of net primary production, a 4% increase in carbon emissions, and a potential loss of US $42 billion a year. It is, therefore, important to restore, enhance and conserve these grasslands to sustain natural plant communities and the livelihoods of those that rely on them. We installed low cost rock structures (media lunas) to assess their ability to restore grasslands by slowing water flow, reducing erosion and improving plant establishment. Our treatments included sites with small and large rock structures that were seeded with a native seed mix as well as sites with no seed or rock and sites with only seed addition. We collected summer percent cover for plants, litter, and rock and spring seedling count data. We also collected soil for nutrient, moisture, and microbial analysis. Within the first year, we found no change in plant cover between rock structures of two rock sizes. We did find, however, an increase in soil moisture, litter, fungal richness, and spring seedling germination within the rock structures, despite a historic drought. This work demonstrates that rock structures can positively impact plants and soils of grasslands even within the first year. Our results suggest that managers should seriously consider employing these low-cost structures to increase short-term plant establishment and possibly, soil health, in grasslands.
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Affiliation(s)
- Trace E Martyn
- School of Natural Resources and the Environment, The University of Arizona, Tucson, AZ, 85721, USA.
| | - Albert Barberán
- Department of Environmental Science, The University of Arizona, Tucson, AZ, 85721, USA
| | - Joseph C Blankinship
- Department of Environmental Science, The University of Arizona, Tucson, AZ, 85721, USA
| | - Mary Miller
- Elkhorn Ranch, Tucson, AZ, 85736, USA
- Altar Valley Conservation Alliance, Tucson, AZ, 85736, USA
| | - Ben Yang
- Department of Environmental Science, The University of Arizona, Tucson, AZ, 85721, USA
| | - Albert Kline
- School of Natural Resources and the Environment, The University of Arizona, Tucson, AZ, 85721, USA
| | - Elise S Gornish
- School of Natural Resources and the Environment, The University of Arizona, Tucson, AZ, 85721, USA
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Zupichiatti V, Zeballos SR, Whitworth‐Hulse JI, Gurvich DE. Survival and growth of cactus species after a wildfire in central Argentina: Differences among species and the effects of microenvironment characteristics. AUSTRAL ECOL 2021. [DOI: 10.1111/aec.13102] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Veronica Zupichiatti
- Facultad de Ciencias Exactas, Físicas y Naturales Universidad Nacional de Córdoba Córdoba Argentina
| | - Sebastian R. Zeballos
- Facultad de Ciencias Exactas, Físicas y Naturales Universidad Nacional de Córdoba Córdoba Argentina
- Instituto Multidisciplinario de Biología Vegetal (FCEFyN, CONICET‐UNC) Av. Vélez Sarsfield 1611, CC495 Córdoba CP5000 Argentina
| | - Juan I. Whitworth‐Hulse
- Grupo de Estudios Ambientales – IMASL Universidad Nacional de San Luis & CONICET San Luis Argentina
| | - Diego E. Gurvich
- Facultad de Ciencias Exactas, Físicas y Naturales Universidad Nacional de Córdoba Córdoba Argentina
- Instituto Multidisciplinario de Biología Vegetal (FCEFyN, CONICET‐UNC) Av. Vélez Sarsfield 1611, CC495 Córdoba CP5000 Argentina
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5
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Gouws CA, Haussmann NS, le Roux PC. Seed trapping or a nurse effect? Disentangling the drivers of fine-scale plant species association patterns in a windy environment. Polar Biol 2021. [DOI: 10.1007/s00300-021-02898-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Effect of shade and precipitation on germination and seedling establishment of dominant plant species in an Andean arid region, the Bolivian Prepuna. PLoS One 2021; 16:e0248619. [PMID: 33788871 PMCID: PMC8011746 DOI: 10.1371/journal.pone.0248619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Accepted: 03/02/2021] [Indexed: 11/25/2022] Open
Abstract
Germination and seedling establishment are two critical processes in the life cycle of plants. Seeds and seedlings must pass through a series of abiotic and biotic filters in order to recruit as members of their communities. These processes are part of the regeneration niche of the species. In arid regions, the regeneration niche is frequently associated to facilitation by shade. Facilitation is a positive interaction between plants, in which one of them acts as a benefactor (the nurse) of the other (the beneficiary). The result of this interaction can be reflected in the increased growth, survival, and/or reproduction of the beneficiary plant. In this study, we determined experimentally the effect of shade and irrigation on the germination and early survival of dominant species of a semi-arid Andean region, the Bolivian Prepuna. An experiment with Acacia feddeana, Prosopis ferox, Cercidium andicola (woody species), Parodia maassii, and Oreocereus celsianus (cactus species) was carried out at an experimental garden in La Paz, Bolivia, with a bifactorial design, considering shaded and unshaded pots, subjected to two irrigation treatments (≈50 and 80 mm of rainfall during the whole study period). Microenvironmental conditions did not affect the seed germination of the woody species. However, they showed differences in seedling survival: A. feddeana survived better under shade, whereas P. ferox and C. andicola survived better without shade. Cercidium andicola, compared to P. ferox, was more affected by shade and low irrigation. Although germination success of cacti was low, both species germinated better under shade and with high irrigation. These results showed differences in the regeneration niche of dominant species of the Prepuna which may favor their coexistence and which may be characteristic of other dry Andean regions.
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Pérez HE, Chumana LAO. Enhancing Conservation of a Globally Imperiled Rockland Herb ( Linum arenicola) through Assessments of Seed Functional Traits and Multi-Dimensional Germination Niche Breadths. PLANTS 2020; 9:plants9111493. [PMID: 33167381 PMCID: PMC7694399 DOI: 10.3390/plants9111493] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 10/29/2020] [Accepted: 10/30/2020] [Indexed: 12/18/2022]
Abstract
Humans currently face an extraordinary period of plant biodiversity loss. One strategy to stem further losses involves the development of species-level recovery plans that guide conservation actions. Seeds represent an important component in the life history of plants and are crucial for conservation activities. Yet, most recovery plans contain meager seed biology information. We set out to examine seed functional traits and germination niche breadth of Linum arenicola seeds exposed to a range of thermal, photoperiodic, and salinity gradients to gain perspectives on the seed biology of this endangered species that may inform conservation decision making and assist recovery plan development. We found that fresh seeds possess non-deep physiological dormancy, which may be alleviated via a four-week dry after-ripening treatment. The germination response of non-dormant seeds is subsequently promoted by constant rather than alternating temperatures. The optimum germination temperature range is 20–22 °C. Non-dormant seeds do not possess an absolute light requirement for germination, but are sensitive to low levels of salinity (EC50 = 6.34 ppth NaCl). The narrow thermal and salinity germination niche breadths reported here suggest a specialized reproductive strategy that may require careful consideration when planning ex and in situ conservation activities.
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Affiliation(s)
- Héctor Eduardo Pérez
- Department of Environmental Horticulture, University of Florida, 2047 IFAS Research Drive, Gainesville, FL 32611, USA;
- Correspondence: ; Tel.: +1-352-273-4503
| | - Luis Andres Ochoa Chumana
- Department of Environmental Horticulture, University of Florida, 2047 IFAS Research Drive, Gainesville, FL 32611, USA;
- Ministerio de Agricultura y Ganadería, Unidad de Gestión Distrital de Desarrollo Productivo, 24D01, Calle 10 de Agosto y Juan Montalvo, Santa Elena-Santa Elena, Ecuador
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8
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Cáceres Y, Schrieber K, Lachmuth S, Auge H, Argibay D, Renison D, Hensen I. Effects of altitude, land use and microsites on early life performance of a high mountain tree: Insights from an in situ sowing experiment. DIVERS DISTRIB 2019. [DOI: 10.1111/ddi.12956] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Affiliation(s)
- Yolanda Cáceres
- Institute of Biology/Geobotany and Botanical Garden Martin Luther University Halle Wittenberg Halle (Saale) Germany
- German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐Leipzig Leipzig Germany
| | - Karin Schrieber
- Institute of Biology/Geobotany and Botanical Garden Martin Luther University Halle Wittenberg Halle (Saale) Germany
- Department Chemical Ecology, Faculty of Biology Bielefeld University Bielefeld Germany
| | - Susanne Lachmuth
- Institute of Biology/Geobotany and Botanical Garden Martin Luther University Halle Wittenberg Halle (Saale) Germany
- German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐Leipzig Leipzig Germany
| | - Harald Auge
- German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐Leipzig Leipzig Germany
- Department of Community Ecology Helmholtz – Centre for Environmental Research – UFZ Halle (Saale) Germany
| | - Daihana Argibay
- Instituto de Investigaciones Biológicas y Tecnológicas Centro de Ecología y Recursos Naturales Renovables (CONICET – Universidad Nacional de Córdoba) Córdoba Argentina
| | - Daniel Renison
- Instituto de Investigaciones Biológicas y Tecnológicas Centro de Ecología y Recursos Naturales Renovables (CONICET – Universidad Nacional de Córdoba) Córdoba Argentina
| | - Isabell Hensen
- Institute of Biology/Geobotany and Botanical Garden Martin Luther University Halle Wittenberg Halle (Saale) Germany
- German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐Leipzig Leipzig Germany
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9
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Interaction of land management and araucaria trees in the maintenance of landscape diversity in the highlands of southern Brazil. PLoS One 2018; 13:e0206805. [PMID: 30462660 PMCID: PMC6248941 DOI: 10.1371/journal.pone.0206805] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 10/19/2018] [Indexed: 11/19/2022] Open
Abstract
In the southern Brazilian highlands, pre-Columbian societies created domesticated landscapes through the use and management of forests, including nurse Araucaria angustifolia trees, a common conifer in these regions. Nowadays, local smallholders still use traditional practices, such as burning, to promote vegetation for cattle grazing in highland grasslands. Even though burning is normally of small extent and low frequency, such management can slow down natural forest expansion and contribute to the maintenance of grasslands, by opposing the facilitative effect of nurse araucaria trees. To comprehend the interplay between human cultural management, species interactions and the environment, it is important to better understand how these relations affect diversity and composition. Our goal was to investigate how land management, biotic interactions and abiotic factors affect saplings species richness, abundance and composition. We hypothesized that (1) land management would decrease sapling richness and abundance and change sapling composition, (2) nurse araucaria trees would increase species richness and abundance and change sapling composition, and (3) the interactive effect between land management and nurse araucaria trees would shape sapling richness, abundance and composition. Data were collected in unmanaged and managed conditions, both beneath araucaria crowns and in nearby treeless areas. Our results indicate that abundance and species composition are affected by land management and araucaria crown influence. The highest values of sapling abundance were found beneath crowns in unmanaged areas. Species composition changed between all assessed combinations of land management and crown influence. Our study demonstrates the major roles of land management and facilitation in structuring communities, despite the effects of rock and grass cover. Moreover, our results clarify patterns and processes that may emerge in natural highland grasslands, such as the conversion of grasslands into forests and the loss of cultural landscapes when the main local management actions are excluded.
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10
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Lindow-López L, Galíndez G, Sühring S, Pastrana-Ignes V, Gorostiague P, Gutiérrez A, Ortega-Baes P. Do cacti form soil seed banks? An evaluation using species from the Southern Central Andes. PLANT BIOLOGY (STUTTGART, GERMANY) 2018; 20:1053-1058. [PMID: 29932289 DOI: 10.1111/plb.12868] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Accepted: 06/19/2018] [Indexed: 06/08/2023]
Abstract
There is controversy over whether cactus species form soil seed banks. Although it is commonly assumed that cacti do not form seed banks, very few studies have evaluated them. In this work, we analysed whether cactus species form soil seed banks, studying seed distribution, seed density and seed longevity in the Southern Central Andes. Soil samples were collected in two microhabitats (under nurse plants and in bare areas) at 12 selected sites. We determined seed presence-absence, density and distribution for 32 native cactus species. Seed longevity for six of these species was determined through a burial experiment. We recorded viable seeds for 62.5% of the 32 evaluated species, finding variation in seed density between microenvironments and among populations. In some species, the highest seed density was found under potential nurse plants. Seed germination and seed viability decreased with burial time, with seed longevity always being <24 months after burial. Our results show strong evidence that cactus species do form seed banks. Seed density can vary between microenvironments and among populations, suggesting that cactus-nurse plant associations can also be explained by differential seed dispersal and not only by differential establishment. We found that Echinopsis and Gymnocalycium species form short-term seed banks. Our results will help to better understand the population dynamics of cactus species, a focal species group for conservation actions because many of them are threatened by human activities.
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Affiliation(s)
- L Lindow-López
- Laboratorio de Investigaciones Botánicas (LABIBO), Facultad de Ciencias Naturales, Universidad Nacional de Salta-CONICET, Salta, Argentina
| | - G Galíndez
- Laboratorio de Investigaciones Botánicas (LABIBO), Facultad de Ciencias Naturales, Universidad Nacional de Salta-CONICET, Salta, Argentina
| | - S Sühring
- Laboratorio de Investigaciones Botánicas (LABIBO), Facultad de Ciencias Naturales, Universidad Nacional de Salta-CONICET, Salta, Argentina
| | - V Pastrana-Ignes
- Laboratorio de Investigaciones Botánicas (LABIBO), Facultad de Ciencias Naturales, Universidad Nacional de Salta-CONICET, Salta, Argentina
| | - P Gorostiague
- Laboratorio de Investigaciones Botánicas (LABIBO), Facultad de Ciencias Naturales, Universidad Nacional de Salta-CONICET, Salta, Argentina
| | - A Gutiérrez
- Laboratorio de Investigaciones Botánicas (LABIBO), Facultad de Ciencias Naturales, Universidad Nacional de Salta-CONICET, Salta, Argentina
| | - P Ortega-Baes
- Laboratorio de Investigaciones Botánicas (LABIBO), Facultad de Ciencias Naturales, Universidad Nacional de Salta-CONICET, Salta, Argentina
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11
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García-Ruiz M, Ruán-Tejeda I, Zuloaga-Aguilar MS, Íñiguez-Dávalos LI. Characterization of endozoochorous dispersal of pitayo Stenocereus queretaroensis, in Autlán, Jalisco, Mexico. ETHOL ECOL EVOL 2018. [DOI: 10.1080/03949370.2017.1423114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Affiliation(s)
- Miriam García-Ruiz
- Departamento de Ecología y Recursos Naturales, Universidad de Guadalajara, Av. Independencia Nacional 151, Autlán 48900, Jalisco, México
| | - Irma Ruán-Tejeda
- Departamento de Ecología y Recursos Naturales, Universidad de Guadalajara, Av. Independencia Nacional 151, Autlán 48900, Jalisco, México
| | - Martha S. Zuloaga-Aguilar
- Departamento de Ecología y Recursos Naturales, Universidad de Guadalajara, Av. Independencia Nacional 151, Autlán 48900, Jalisco, México
| | - Luis I. Íñiguez-Dávalos
- Departamento de Ecología y Recursos Naturales, Universidad de Guadalajara, Av. Independencia Nacional 151, Autlán 48900, Jalisco, México
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López-Flores D, Zavala-Hurtado JA, Golubov J, Mandujano MC. SPATIAL DISTRIBUTION AND ASSOCIATION WITH NURSE PLANTS OF THE BISHOP'S MITER CACTUS ASTROPHYTUM MYRIOSTIGMA IN THE CHIHUAHUAN DESERT. SOUTHWEST NAT 2018. [DOI: 10.1894/0038-4909-63-3-186] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Donají López-Flores
- Doctorado en Ciencias Biológicas y de la Salud, Universidad Autónoma Metropolitana, Calzada del Hueso 1100, Colonia Villa Quietud, Coyoacán, Ciudad de México, México, 04960 (DLF)
| | - J. Alejandro Zavala-Hurtado
- Laboratorio de Ecología, Departamento de Biología, Universidad Autónoma Metropolitana-Iztapalapa, Av. San Rafael Atlixco 186, Colonia Vicentina. Iztapalapa, Ciudad de México, México, 09340 (JAZH)
| | - Jordan Golubov
- Laboratorio de Ecología y Sistemática Vegetal, Departamento El Hombre y Su Ambiente, Universidad Autónoma Metropolitana-Xochimilco, Calzada Del Hueso 1100, Colonia Villa Quietud, Coyoacán, Ciudad de México, México, 04960 (JG)
| | - María C. Mandujano
- Laboratorio de Genética y Ecología, Departamento de Ecología de la Biodiversidad, Instituto de Ecología, Universidad Nacional Autónoma de México, UNAM, Circuito Exterior S/N anexo Jardín Botánico exterior, Ciudad Universitaria, Coyoacán, Ciudad de Mé
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Loayza AP, Herrera-Madariaga MA, Carvajal DE, García-Guzmán P, Squeo FA. Conspecific plants are better 'nurses' than rocks: consistent results revealing intraspecific facilitation as a process that promotes establishment in a hyper-arid environment. AOB PLANTS 2017; 9:plx056. [PMID: 29218138 PMCID: PMC5710651 DOI: 10.1093/aobpla/plx056] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Accepted: 10/19/2017] [Indexed: 05/30/2023]
Abstract
Harsh environmental conditions in arid ecosystems limit seedling recruitment to microhabitats under nurse structures, such as shrubs or rocks. These structures, however, do not necessarily afford the same benefits to plants because nurse rocks provide only physical nurse effects, whereas nurse plants can provide both physical and biological nurse effects. Nevertheless, if the nurse plant is a conspecific, the benefits it provides may be outweighed by higher mortality due to negative density-dependent processes; consequently, negative density-dependence is expected to limit plants from acting as nurses to their own seedlings. The degree to which an abiotic nurse may be more beneficial than a conspecific one remains largely unexplored. Here, we examine the role and elucidate the mechanisms by which conspecific plants and rocks promote plant establishment in a hyper-arid desert. For 4 years, we examined establishment patterns of Myrcianthes coquimbensis (Myrtaceae), a threatened desert shrub that recruits solely in rock cavities and under conspecific shrubs. Specifically, we characterized these microhabitats, as well as open interspaces for comparison, and conducted germination, seed removal and seedling survival experiments. Our results revealed that conspecific shrubs and nurse rocks modified environmental conditions in similar ways; soil and air temperatures were lower, and water availability was higher than in open interspaces. We found no evidence on negative density-dependent recruitment: seed removal was lowest and seedling emergence highest under conspecific plants, moreover seedling survival probabilities were similar in rock cavities and under conspecific plants. We conclude that the probability of establishment was highest under conspecific plants than in other microhabitats, contrasting what is expected under the Janzen-Connell recruitment model. We suggest that for species living in stressful environments, population regulation may be a function of positive density-dependence and intraspecific facilitation may be a process that promotes the persistence of some plant species within a community.
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Affiliation(s)
- Andrea P Loayza
- Department of Biology, University of La Serena, Av. Raúl Bitrán 1305, La Serena 1720256, Chile
| | | | - Danny E Carvajal
- Department of Biology, University of La Serena, Av. Raúl Bitrán 1305, La Serena 1720256, Chile
- Institute of Ecology and Biodiversity (IEB), Las Palmeras 3425, Ñuñoa, Santiago 7800003, Chile
| | - Patricio García-Guzmán
- Department of Biology, University of La Serena, Av. Raúl Bitrán 1305, La Serena 1720256, Chile
- Institute of Ecology and Biodiversity (IEB), Las Palmeras 3425, Ñuñoa, Santiago 7800003, Chile
| | - Francisco A Squeo
- Department of Biology, University of La Serena, Av. Raúl Bitrán 1305, La Serena 1720256, Chile
- Institute of Ecology and Biodiversity (IEB), Las Palmeras 3425, Ñuñoa, Santiago 7800003, Chile
- Center for Advanced Studies in Arid Zones (CEAZA), Av. Raúl Bitrán 1305, La Serena 1720256, Chile
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14
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Ordoñez-Salanueva CA, Orozco-Segovia A, Canales-Martínez M, Seal CE, Pritchard HW, Flores-Ortiz CM. Ecological longevity of Polaskia chende (Cactaceae) seeds in the soil seed bank, seedling emergence and survival. PLANT BIOLOGY (STUTTGART, GERMANY) 2017; 19:973-982. [PMID: 28787550 DOI: 10.1111/plb.12611] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Accepted: 08/02/2017] [Indexed: 06/07/2023]
Abstract
Soil seed banks are essential elements of plant population dynamics, enabling species to maintain genetic variability, withstand periods of adversity and persist over time, including for cactus species. However knowledge of the soil seed bank in cacti is scanty. In this study, over a 5-year period we studied the seed bank dynamics, seedling emergence and nurse plant facilitation of Polaskia chende, an endemic columnar cactus of central Mexico. P. chende seeds were collected for a wild population in Puebla, Mexico. Freshly collected seeds were sown at 25 °C and 12-h photoperiod under white light, far-red light and darkness. The collected seeds were divided in two lots, the first was stored in the laboratory and the second was use to bury seeds in open areas and beneath a shrub canopy. Seeds were exhumed periodically over 5 years. At the same time seeds were sown in open areas and beneath shrub canopies; seedling emergence and survival were recorded over different periods of time for 5 years. The species forms long-term persistent soil seed banks. The timing of seedling emergence via germination in the field was regulated by interaction between light, temperature and soil moisture. Seeds entered secondary dormancy at specific times according to the expression of environmental factors, demonstrating irregular dormancy cycling. Seedling survival of P. chende was improved under Acacia constricta nurse plants. Finally, plant facilitation affected the soil seed bank dynamics as it promoted the formation of a soil seed bank, but not its persistence.
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Affiliation(s)
- C A Ordoñez-Salanueva
- Laboratorio de Fisiología Vegetal, UBIPRO, Facultad de Estudios Superiores-Iztacala, Universidad Nacional Autónoma de México, Tlalnepantla, México
| | - A Orozco-Segovia
- Instituto de Ecología, Universidad Nacional Autónoma de México, Ciudad Universitaria, México
| | - M Canales-Martínez
- Laboratorio de Farmacognosia, UBIPRO, Facultad de Estudios Superiores-Iztacala, Universidad Nacional Autónoma de México, Tlalnepantla, México
| | - C E Seal
- Department of Comparative Plant and Fungal Biology, Royal Botanic Gardens, Kew, UK
| | - H W Pritchard
- Department of Comparative Plant and Fungal Biology, Royal Botanic Gardens, Kew, UK
| | - C M Flores-Ortiz
- Laboratorio de Fisiología Vegetal, UBIPRO, Facultad de Estudios Superiores-Iztacala, Universidad Nacional Autónoma de México, Tlalnepantla, México
- Laboratorio Nacional en Salud, Facultad de Estudios Superiores-Iztacala, Universidad Nacional Autónoma de México, Tlalnepantla, México
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15
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Quipildor VB, Mathiasen P, Premoli AC. Population Genetic Structure of the Giant Cactus Echinopsis terscheckii in Northwestern Argentina Is Shaped by Patterns of Vegetation Cover. J Hered 2017; 108:469-478. [PMID: 28369439 DOI: 10.1093/jhered/esx027] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Accepted: 03/23/2017] [Indexed: 11/13/2022] Open
Abstract
Species inhabiting drylands commonly depend on the surrounding vegetation for recruitment under stress, while competition may affect populations in moister environments. Our objective was to analyze how different climates and vegetation affect the fine-scale spatial genetic structure (SGS) of the columnar cactus Echinopsis terscheckii. At 4 sites, we estimated vegetation cover by digitized patches and the normalized difference vegetation index (NDVI). We mapped 30 individuals per population and collected tissue for isozyme electrophoresis using 15 putative loci. Spatial autocorrelation between all possible genotype pairs and the number of genetically homogeneous groups and families were calculated for each population. Greater cover (66%) and average NDVI values were detected in the most humid habitat that consisted of fewer, larger, and more dispersed vegetation patches. All populations were genetically diverse and showed significant SGS. Positive correlations were found between the distance at which maximum autocorrelation and kinship values were reached and vegetation area and patch size. Also higher NDVI values were associated with lower number of patches. Populations exposed to higher precipitation and vegetation cover consisted of sparse individuals that clustered at larger distances whereas vegetation patches in arid climates produced groups of closely related genotypes at small distances. These results support the stress-gradient genetic hypothesis. Under water stress, facilitation promotes establishment underneath patchy vegetation resulting in fine-scale family structure. In moister xerophilous forests, competition for resources, that is, light, results in sparse individuals and thus coarse-scale neighborhoods. This information can guide conservation and/or restoration efforts, such as the spatial scale to be considered in germplasm collection.
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Affiliation(s)
- Vilma B Quipildor
- INIBIOMA CONICET, Universidad Nacional del Comahue, Quintral 1250, Bariloche 8400, Argentina
| | - Paula Mathiasen
- INIBIOMA CONICET, Universidad Nacional del Comahue, Quintral 1250, Bariloche 8400, Argentina
| | - Andrea C Premoli
- INIBIOMA CONICET, Universidad Nacional del Comahue, Quintral 1250, Bariloche 8400, Argentina
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16
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Pérez-Sánchez RM, Flores J, Jurado E, González-Salvatierra C. Growth and ecophysiology of succulent seedlings under the protection of nurse plants in the Southern Chihuahuan Desert. Ecosphere 2015. [DOI: 10.1890/es14-00408.1] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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17
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Fujita T, Mizuno K. Role of nurse rocks on woody plant establishment in a South African grassland. TROPICS 2015. [DOI: 10.3759/tropics.24.57] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- Tomohiro Fujita
- Graduate School of Asian and African Area Studies, Kyoto University
- Graduate School of Letters, Kyoto University
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18
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Ontogenetic shifts in plant-plant interactions in a rare cycad within angiosperm communities. Oecologia 2014; 175:725-35. [PMID: 24652529 DOI: 10.1007/s00442-014-2929-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Accepted: 03/05/2014] [Indexed: 10/25/2022]
Abstract
Gymnosperms and angiosperms can co-occur within the same habitats but key plant traits are thought to give angiosperms an evolutionary competitive advantage in many ecological settings. We studied ontogenetic changes in competitive and facilitative interactions between a rare gymnosperm (Dioon sonorense, our target species) and different plant and abiotic neighbours (conspecific-cycads, heterospecific-angiosperms, or abiotic-rocks) from 2007 to 2010 in an arid environment of northwestern Mexico. We monitored survival and growth of seedlings, juveniles, and adults of the cycad Dioon sonorense to evaluate how cycad survival and relative height growth rate (RHGR) responded to intra- and interspecific competition, canopy openness, and nearest neighbour. We tested spatial associations among D. sonorense life stages and angiosperm species and measured ontogenetic shifts in cycad shade tolerance. Canopy openness decreased cycad survival while intraspecific competition decreased survival and RHGR during early ontogeny. Seedling survival was higher in association with rocks and heterospecific neighbours where intraspecific competition was lower. Shade tolerance decreased with cycad ontogeny reflecting the spatial association of advanced stages with more open canopies. Interspecific facilitation during early ontogeny of our target species may promote its persistence in spite of increasing interspecific competition in later stages. We provide empirical support to the long-standing assumption that marginal rocky habitats serve as refugia from angiosperm competition for slow-growing gymnosperms such as cycads. The lack of knowledge of plant-plant interactions in rare or endangered species may hinder developing efficient conservation strategies (e.g. managing for sustained canopy cover), especially under the ongoing land use and climatic changes.
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19
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Rojas-Aréchiga M, Mandujano MC, Golubov JK. Seed size and photoblastism in species belonging to tribe Cacteae (Cactaceae). JOURNAL OF PLANT RESEARCH 2013; 126:373-386. [PMID: 23065043 DOI: 10.1007/s10265-012-0526-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2012] [Accepted: 09/11/2012] [Indexed: 06/01/2023]
Abstract
The response of seed germination towards light and the relationship to seed traits has been studied particularly well in tropical forests. Several authors have shown a clear adaptive response of seed size and photoblastism, however, the evolutionary significance of this relationship for species inhabiting arid environments has not been fully understood and only some studies have considered the response in a phylogenetic context. We collected seeds from 54 cacti species spread throughout the tribe Cacteae to test whether there was correlated evolution of photoblastism, seed traits and germination using a reconstructed phylogeny of the tribe. For each species we determined the photoblastic response under controlled conditions, and seed traits, and analyzed the results using phylogenetically independent contrasts. All studied species were positive photoblastic contrasting with the basal Pereskia suggesting an early evolution of this trait. Seeds from basal species were mostly medium-sized, diverging into two groups. Seeds tend to get smaller and lighter suggesting an evolution to smaller sizes. No evidence exists of a relationship between seed size and photoblastic response suggesting that the photoblastic response within members of this tribe is not adaptive though it is phylogenetically fixed and that is coupled with environmental cues that fine tune the germination response.
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Affiliation(s)
- Mariana Rojas-Aréchiga
- Instituto de Ecología, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, Mexico, Mexico
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20
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Intraspecific Directed Deterrence by the Mustard Oil Bomb in a Desert Plant. Curr Biol 2012; 22:1218-20. [DOI: 10.1016/j.cub.2012.04.051] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2012] [Revised: 04/23/2012] [Accepted: 04/24/2012] [Indexed: 11/22/2022]
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21
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Ruderality in extreme-desert cacti? Population effects of chronic anthropogenic disturbance on Echinocereus lindsayi. POPUL ECOL 2012. [DOI: 10.1007/s10144-012-0307-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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22
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Castro J, Allen CD, Molina-Morales M, Marañón-Jiménez S, Sánchez-Miranda Á, Zamora R. Salvage Logging Versus the Use of Burnt Wood as a Nurse Object to Promote Post-Fire Tree Seedling Establishment. Restor Ecol 2010. [DOI: 10.1111/j.1526-100x.2009.00619.x] [Citation(s) in RCA: 95] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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