Figure - available from: Nature Plants
This content is subject to copyright. Terms and conditions apply.
SEM assessing direct and indirect effects on the fertile island effect a–c, The effects of climate (aridity (ARID), rainfall seasonality (SEAS)), soil (pH and sand (SAND) content), plants (perennial cover (COV), perennial plant richness (RICH)), plant height (HT), plant shape (SHAPE), leaf area (AREA), leaf length (LNGTH), canopy width (WIDTH), palatability (PALAT), deciduousness (DECID), resprouting ability (RESP) and allelopathy (ALLEL)) and grazing (standardized grazing pressure) are considered for soil decomposition (a), soil fertility (b) and soil and water conservation (c) after accounting for the effects of location (latitude, cosine longitude, sine longitude). Standardized path coefficients, adjacent to the arrows, are analogous to partial correlation coefficients and indicative of the effect size of the relationship. Pathways are significantly negative (red unbroken line), significantly positive (blue unbroken line) or mixed significantly negative and significantly positive (black unbroken lines). Non-significant pathways are not shown in the models. Model fit details are as follows: a, organic matter decomposition: χ² = 31.9, d.f. = 26, P = 0.20, R² = 0.17, r.m.s.e.a. < 0.001, Bollen–Stine = 0.40 (2,000 bootstraps); b, fertility: χ² = 31.9, d.f. = 26, P = 0.20, R² = 0.19, r.m.s.e.a. < 0.001, Bollen–Stine = 0.40 (2,000 bootstraps); c, conservation: χ² = 31.9, d.f. = 26, P = 0.20, R² = 0.10, r.m.s.e.a. < 0.001, Bollen–Stine = 0.40 (2,000 bootstraps). N = 288 for all analyses. Source data
Source publication
Perennial plants create productive and biodiverse hotspots, known as fertile islands, beneath their canopies. These hotspots largely determine the structure and functioning of drylands worldwide. Despite their ubiquity, the factors controlling fertile islands under conditions of contrasting grazing by livestock, the most prevalent land use in dryla...
Citations
... Due to its fine-scale nature, microclimate can vary dramatically over short distances and time periods, playing a crucial role in the survival and reproduction of organisms. For instance, soils exhibit high spatial variation, which directly impacts the distribution of all forms of biodiversity, including microorganisms, plants, invertebrates and other animals (Garten et al. 2007, Eldridge et al. 2024. Topography also greatly influences local conditions, such as temperature, water availability, solar radiation and wind currents Nunes et al. 2019, De Frenne et al. 2021, Kemppinen et al. 2024. ...
Much of the work developed on biodiversity dynamics due to climate change focuses on large scales. Yet, we know that small scale is critical to fully understand biodiversity change, particularly for plants and small or less mobile organisms which might seek refuge in sites that keep specific microclimatic and biotic conditions dampening the effects of large-scale changes. The project BASS - Biodiversity Assessment at Small Scales - aims to explore the intricate relationships between small-scale environmental variations in space and time and biodiversity patterns. Central to our study is researching how microclimatic conditions, such as potential solar radiation, influence species occurrence, abundance, community composition and biotic interactions within a Mediterranean context. Our objectives include gaining a deeper understanding of the effects of localised environmental conditions and their change in time on biodiversity, providing critical data for an under-researched Mediterranean Biodiversity Hotspot region, and examining the dynamics of small-sized species, particularly plants and invertebrates. We have established a network of 16 fixed sampling points across the Lisbon University field station - Herdade da Ribeira Abaixo (HRA), Grândola (South Portugal): eight with high and eight with low potential solar radiation. Each of these plots will serve as a 'mesocosm' for detailed ecological studies in the next decades. This framework will support a variety of research projects each focusing on different taxa and questions, including Masters' theses, PhD dissertations and independent studies, thereby fostering a collaborative research environment. By integrating previously collected data during the last three decades with new findings, we aim to offer valuable insights into the processes underlying ecosystem functioning and change at small spatial scales. This project not only addresses fundamental ecological questions, but also contributes to sustainable landscape management and biodiversity conservation efforts.
Борьба с засухой является важной задачей в мире. Quercus robur L. относится к засухоустойчивым видам, которые применяются в агролесомелиорации территорий с засушливым климатом. Абсцизовая кислота (АBA) является фитогормоном, участвующим в формировании адаптации к засухе. Фермент абсцизная альдегидоксидаза (AAO) обеспечивает синтез ABA. Цель работы – оценить экспрессию гена AAO у двух популяций Q. robur во время фазы облиствления и плодоношения в условиях засухи. В двух популяциях Q. roburбыли отобраны образцы листьев в начале и середине вегетации: облиствления и плодоношения. Оценка транскрипционной активности гена AAO производилась с помощью ОТ-ПЦР-РВ и расчета его относительной экспрессии. По результатам оценки кривых плавления ампликонов была подобрана пара праймеров для расчета относительной экспрессии AAO у Q. robur. Оценка транскрипционной активности AAO в двух популяций Q. robur показала различия в середине вегетационного периода во время интенсивной засухи. Было выявлено, что особи Q. robur, произрастающие на территории Нижневолжской станции по селекции древесных пород, обладают более высокой транскрипционной активностью AAO. Полученные результаты могут быть использованы для генотипирования особей Q. robur с высокой экспрессией AAO в различных популяциях для создания коллекции засухоустойчивых древесных растений.
