1,586 research outputs found

    Efecto de dos especies de plantas invasoras fijadoras de nitrógeno sobre las propiedades químicas del suelo en el centro-sur de Chile

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    Dos especies invasoras leñosas, Acacia dealbata y Teline monspessulana (Fabaceae), ampliamente distribuidas en el centrosurde Chile, poseen la capacidad de fijar biológicamente el nitrógeno atmosférico y contribuir a la fertilidad del suelo. Sepresentan evidencias de potenciales cambios ocasionados por estas especies en las propiedades químicas del suelo en áreasaltamente degradadas de la Región del Bío-Bío, Chile.Dos especies invasoras leñosas, Acacia dealbata y Teline monspessulana (Fabaceae), ampliamente distribuidas en el centrosurde Chile, poseen la capacidad de fijar biológicamente el nitrógeno atmosférico y contribuir a la fertilidad del suelo. Sepresentan evidencias de potenciales cambios ocasionados por estas especies en las propiedades químicas del suelo en áreasaltamente degradadas de la Región del Bío-Bío, Chile

    Nutritional contribution of atmospheric deposition to the Strandveld vegetation of West Coast South Africa Justine Muhoro Nyaga.

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    Includes abstract.Includes bibliographical references.Ecosystem nutrient availability depends on the balance between rates of nutrient inputs and losses. Nutrients may be lost through fire and displacement of ash, herbivory, leaching and volatilization. The main pathways through which nutrients may be acquired are weathering of rock and atmospheric deposition. Symbiotic and free-living diazotrophic bacteria and blue green algae also contribute N. In ecosystems with limited occurrence of N₂-fixation and occurring on low-nutrient bedrock, atmospheric deposition is the most significant source of nutrients. Nutrients from atmospheric deposition may be of natural or anthropogenic origin, and can be “wet-deposited” dissolved in precipitation and “dry-deposited” when aerosols settle out of the atmosphere onto plant and soil surfaces. Studies on nutrient cycling around the world suggest that nutrient deposition can provide substantial amounts of nutrients to coastal ecosystems, although mineral weathering of rocks can also a significant source. Limited prior work on deposition in coastal areas of South Africa suggests that nutrient deposition could be an important component of nutrient budgets in the Cape Floristic Region. The west coast of South Africa borders a section of the Atlantic Ocean that is highly productive and characterized by strong seasonal winds, rough waters and strong wave action. This area is home to the Strandveld vegetation, which grows on marine-derived soils. Based on this, I hypothesized that marine aerosol deposition is a significant source of nutrients for the vegetation in west coast South Africa. To test this hypothesis, I examined the spatial and temporal characteristics of atmospheric deposition as well as the climatic and ecological characteristics of the area

    Global effects of non-native tree species on multiple ecosystem services

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    Non-native tree (NNT) species have been transported worldwide to create or enhance services that are fundamental for human well-being, such as timber provision, erosion control or ornamental value; yet NNTs can also produce undesired effects, such as fire proneness or pollen allergenicity. Despite the variety of effects that NNTs have on multiple ecosystem services, a global quantitative assessment of their costs and benefits is still lacking. Such information is critical for decision-making, management and sustainable exploitation of NNTs. We present here a global assessment of NNT effects on the three main categories of ecosystem services, including regulating (RES), provisioning (PES) and cultural services (CES), and on an ecosystem disservice (EDS), i.e. pollen allergenicity. By searching the scientific literature, country forestry reports, and social media, we compiled a global data set of 1683 case studies from over 125 NNT species, covering 44 countries, all continents but Antarctica, and seven biomes. Using differentmeta-analysis techniques, we found that, while NNTs increase most RES (e.g. climate regulation, soil erosion control, fertility and formation), they decrease PES (e.g. NNTs contribute less than native trees to global timber provision). Also, they have different effects on CES (e.g. increase aesthetic values but decrease scientific interest), and no effect on the EDS considered. NNT effects on each ecosystem (dis)service showed a strong context dependency, varying across NNT types, biomes and socio-economic conditions. For instance, some RES are increased more by NNTs able to fix atmospheric nitrogen, and when the ecosystem is located in low-latitude biomes; some CES are increased more by NNTs in less-wealthy countries or in countries with higher gross domestic products. The effects of NNTs on several ecosystem (dis)services exhibited some synergies (e.g. among soil fertility, soil formation and climate regulation or between aesthetic values and pollen allergenicity), but also trade-offs (e.g. between fire regulation and soil erosion control). Our analyses provide a quantitative understanding of the complex synergies, trade-offs and context dependencies involved for the effects of NNTs that is essential for attaining a sustained provision of ecosystem servicesinfo:eu-repo/semantics/publishedVersio

    Efecto alelopático de la invasora Acacia dealbata Link (Fabaceae) en dos especies de plantas nativas del centro-sur de Chile

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    Plant species that growth close to or under the canopy of Acacia dealbata Link (Fabaceae, subfamily: Mimosoideae) withinits non-native range, survive with difficulty or not at all, especially if they are native. This phenomenon has been attributedto allelopathy; one of the strategies used by A. dealbata to trigger an invasion process. Native species Quillaja saponariaMolina (tree) and Helenium aromaticum (Hook.) H.L. Bailey (herb), share A. dealbata’s range in South-central Chile. Thisstudy was performed on the Mediterranean Biobío Region of Chile. We evaluated the effect of leaves, flowers, pods andseeds of A. dealbata on the germination and early growth of these native species. Biological assays were carried out underlaboratory conditions, based on aqueous extracts and the direct effect of plant material. Leaf litter prevented the germinationof both species and seeds of the invasive species impeded the germination of Q. saponaria. Other plant parts from A.dealbata also induced reductions of hypocotyl and radicle lengths in the native species, reaching over 50 % in some treatmentvalues. All plant parts caused radicle necrosis, preventing the formation of root hairs and, consequently, jeopardizing thesurvival possibility of the recipient species. The results show that A. dealbata can interfere with the establishment of pioneerherbaceous species in ecological succession and can also affect trees if they are reached by the invasion front.Las plantas que crecen cerca o bajo el dosel de Acacia dealbata Link (Fabaceae, subfamilia: Mimosoideae), cuando esta seencuentra en el rango no nativo, sobreviven con dificultad o no lo logran, especialmente si son nativas. Este fenómeno se haatribuido a la alelopatía; una de las estrategias utilizadas por A. dealbata para promover su proceso de invasión. Las especiesnativas Quillaja saponaria Molina (arbórea) y Helenium aromaticum (Hook.) H.L. Bailey (herbácea) comparten el rango dedistribución de A. dealbata en el centro-sur de Chile. El presente trabajo se realizó en la Región del Biobío y se evaluaronlos efectos de hojas, flores, vainas y semillas de A. dealbata en la germinación y crecimiento temprano de las especiesnativas mencionadas. Los ensayos biológicos se llevaron a cabo en condiciones de laboratorio, basados en extractos acuososy efectos directos del material vegetal. Nuestros resultados indicaron que las hojas impidieron la germinación de ambasespecies nativas, pero las semillas impidieron sólo la germinación de Q. saponaria. Otras partes de la planta de A. dealbatatambién indujeron fuertes reducciones de las longitudes del hipocótilo y radícula en las especies nativas, superándose el50% en algunos tratamientos. Todas las partes de la planta causaron necrosis en la radícula, evitando la formación de pelosradicales y, por consiguiente, comprometiendo la posibilidad de supervivencia de las especies receptoras. Estos resultadosmuestran que A. dealbata puede interferir en el establecimiento de especies herbáceas pioneras en la sucesión ecológica ytambién puede afectar especies arbóreas secundarias si son alcanzadas por el frente de invasión

    Effects of forest preservation, livestock exclusion and use of shrubs as potential nurses on planting success of an endangered tree

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    Domestic livestock are widespread in seasonally dry forests, likely causing forest degradation and limiting tree seedling establishment. Shrubs can play an important role in facilitating tree regeneration, by protecting trees from livestock damage and ameliorating unfavorable abiotic conditions. We aimed at disentangling the relative contribution of grazing exclusion, long-term forest conservation, and the potential facilitation effect of shrubs on the performance of saplings of the native tree Kageneckia lanceolata. We planted 400 saplings in grazed and ungrazed areas situated both in a preserved and a degraded forest. In each situation, we established planting plots in three accompanying vegetation treatments: herbs, a non-leguminous spiny shrub and a leguminous spiny shrub. Survival of three-year-old saplings was 10-fold higher in the preserved than in the degraded forest and two-fold higher in the ungrazed than in the grazed site. Differences in survival among accompanying vegetation treatments were much smaller than between grazing treatments. Survival significantly increased with increasing protection by shrubs only in the degraded site. Sapling growth patterns were fairly similar to survival patterns, with no growth in the degraded forest, except for limited growth under both shrubs in the ungrazed site. We conclude that, in selecting plantation sites for the study species, forest condition and grazing exclusion should be prioritized over microsite selection based on neighboring vegetation.Fil: Torres, Romina Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; ArgentinaFil: Pollice, Julieta. Universidad Provincial de Cordoba. Facultad de Turismo y Ambiente.; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; ArgentinaFil: Valfré Giorello, Tatiana Alejandra. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Ecología y Recursos Naturales Renovables; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; ArgentinaFil: Herrero, María Lucrecia. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Ecología y Recursos Naturales Renovables; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; ArgentinaFil: Navarro Ramos, Silvia Elisa. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Ecología y Recursos Naturales Renovables; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; ArgentinaFil: Ibarra Grellet, Ignacio. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Ecología y Recursos Naturales Renovables; ArgentinaFil: Renison, Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Ecología y Recursos Naturales Renovables; Argentin

    State of Knowledge of Soil Biodiversity – Status, Challenges and Potentialities, Report 2020

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    Our well-being and the livelihoods of human societies are highly dependent on biodiversity and the ecosystem services it provides. It is essential that we understand these links and the consequences of biodiversity loss for the various global challenges we currently face, including food insecurity and malnutrition, climate change, poverty and diseases. The Agenda 2030 for Sustainable Development sets out a transformative approach to achieve socio-economic development while conserving the environment. There is increasing attention on the importance of biodiversity for food security and nutrition, especially above-ground biodiversity such as plants and animals. However, less attention is being paid to the biodiversity beneath our feet, soil biodiversity. Yet, the rich diversity of soil organisms drives many processes that produce food, regenerate soil or purify water. In 2002, the Conference of the Parties (COP) to the Convention on Biological Diversity (CBD) decided at its 6th meeting to establish an International Initiative for the Conservation and Sustainable Use of Soil Biodiversity and since then, the Food and Agriculture Organization of the United Nations (FAO) has been facilitating this initiative. In 2012, FAO members established the Global Soil Partnership to promote sustainable soil management and increase attention to this hidden resource. The Status of the World’s Soil Resources (FAO, 2015) concluded that the loss of soil biodiversity is considered one of the main global threats to soils in many regions of the world. The 14th Conference of the Parties invited FAO, in collaboration with other organizations, to consider the preparation of a report on the state of knowledge on soil biodiversity covering its current status, challenges and potentialities. This report is the result of an inclusive process involving 300 scientists from around the world under the auspices of the FAO’s Global Soil Partnership and its Intergovernmental Technical Panel on Soils, the Convention on Biological Diversity, the Global Soil Biodiversity Initiative and the European Commission. The report presents the state of knowledge on soil biodiversity, the threats to it, the solutions that soil biodiversity can provide to problems in different fields, including agriculture, environmental conservation, climate change adaptation and mitigation, nutrition, medicine and pharmaceuticals, remediation of polluted sites, and many others. The report will make a valuable contribution to raising awareness of the importance of soil biodiversity and highlighting its role in finding solutions to today’s global threats; it is a cross-cutting topic at the heart of the alignment of several international policy frameworks, including the Sustainable Development Goals (SDGs) and multilateral environmental agreements. Furthermore, soil biodiversity and the ecosystem services it provides will be critical to the success of the recently declared UN Decade on Ecosystem Restoration (2021-2030) and the upcoming Post- 2020 Global Biodiversity Framework. Soil biodiversity could constitute, if an enabling environment is built, a real nature-based solution to most of the problems humanity is facing today, from the field to the global scale. Therefore efforts to conserve and protect biodiversity should include the vast array of soil organisms that make up more than 25% of the total biodiversity of our planet

    State of Knowledge of Soil Biodiversity: Status, Challenges, and Potentialities

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    This report presents the threats to soil biodiversity and the solutions that soil biodiversity can provide to problems in different fields, including agriculture, environmental conservation, climate change adaptation and mitigation, nutrition, medicine and pharmaceuticals, remediation of polluted sites, and many others. There is increasing attention on the importance of biodiversity for food security and nutrition, especially above-ground biodiversity such as plants and animals. Less attention is being paid to the biodiversity beneath our feet: soil biodiversity. Yet the rich diversity of soil organisms drives many processes that produce food, regenerate soil or purify water. This report is the result of an inclusive process involving more than 300 scientists from around the world under the auspices of FAO's Global Soil Partnership and its Intergovernmental Technical Panel on Soils, the Convention on Biological Diversity, the Global Soil Biodiversity Initiative, and the European Commission

    Biological Flora of Central Europe–Lupinus polyphyllus Lindl

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    The invasive herb Lupinus polyphyllus has been focus of a number of fact sheets worldwide but a comprehensive summary of the species’ taxonomy and morphology, distribution, habitat requirements, and biology has been lacking. This paper gives a thorough account of the species’ systematic position and taxonomy, highlighting the difficulties to delimit taxa, which is related to interbreeding among members of this genus. However, L. polyphyllus var. polyphyllus is apparently the taxon that has naturalized and is regionally invasive in temperate-humid climates worldwide. We also present an updated distribution map of L. polyphyllus in the native and invaded ranges, which highlights seven regions in the world where the species has been established. We show that the climatic niche of L. polyphyllus in the invaded range shifts towards higher summer precipitation and lower isothermality, probably because the invaded range includes subcontinental regions of eastern Europe and western Siberia. The habitats of L. polyphyllus range from rather dry to wet, have moderately acidic to strongly acidic soils, and the species’ indicator values across Europe suggest that it occurs along a gradient from very nutrient poor sites to intermediate to rich sites from northern to southern Europe. The species shows high resistance to both drought and frost. In Central Europe, the species has a stronghold in alpic mountain hay meadows, abandoned meadows and pastures, low and medium altitude hay meadows, anthropogenic herb stands and temperate thickets and scrubs. In northern Europe, the species occurs in anthropogenic herb stands along roads and railroads as well as in abandoned pastures and fields. We also found some doubtful information about L. polyphyllus in the literature. This refers to its description as “rhizomatous perennial” although it lacks rhizomes; an apparently very high longevity of its seeds, which may only be true under artificial conditions in an ex situ seed repository; and a very deep rooting depth, which may not represent the average rooting depth but rather an extreme value. Knowledge about the interrelationships between the species’ future population dynamics and spread and ongoing climate warming is lacking. Finally, our review points out that there is currently no evidence-based strategy for a cost-efficient management of L. polyphyllus although it is among the most problematic non-native plant species in Europe due to its environmental and socio-economic impacts
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