BazTech - Yadda

1

Community level variation in plant leaf traits along an elevation gradient in the semi-arid mountains of Northwest China

Yang Jun-long, Li Xiao-wei

Polish Journal of Ecology

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2022

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vol. 70, nr 4

142--158

EN

An elevation gradient affects temperature, precipitation, soil properties, and other environmental factors important for plant growth, resulting in differential responses of plant functional traits within and between species. Here, three transect lines were established along an elevation gradient of 1500 to 2900 m that spanned four vegetation types: desert grassland, low mountain shrub zone, subalpine coniferous forest, and subalpine shrub zone in a semiarid mountain ecosystem (western part of the Helan Mountains, Northwest China). Nine functional plant traits — leaf nitrogen (LN), leaf carbon (LC), leaf thickness (LT), specific leaf area (SLA), leaf phosphorus, leaf dry matter content, and the leaf carbon/leaf nitrogen (C/N), leaf carbon/leaf phosphorus (C/P), leaf nitrogen/leaf phosphorus (N/P) — were quantified to investigate (1) how the community-weighted means (CWM) and unweighted means (CM) vary; (2) how inter- and intraspecific functional traits vary; and (3) how the climate, topography and soil properties affect plant functional traits at the community level. We found that with rising elevation, SLA and LT increased and then decreased, while C/P and N/P showed opposite trend for both CWM and CM. Additionally, the higher LN and lower C/N were found in subalpine shrub zone. The leaf functional traits between CWM and CM showed no significant difference but a close relationship between them. Generally, all the leaf traits were explained better by interspecific variation than by intraspecific variation, except for N/P. The covariance analysis indicated that LP and LC showed negative covariance effects, whereas all other leaf traits showed positive covariance effects. The contribution to plant leaf traits from altitude was slightly higher than vapor pressure and soil organic carbon. Our major finding emphasize that plant communities in the western Helan Mountains were assembled along elevation primarily via interspecific variation.

2

Biodiversity Versus Stability: the Biological Effect of Plant Functional Traits on Ecosystem Functioning in Grasslands Dominated by Leymus chinensis

Zhao N., Shao X., Wang K.

Polish Journal of Ecology

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2016

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Vol. 64, nr 3

339--349

EN

Although diversity-ecosystem theory predicts that ecosystem functioning is strongly determined by species number, species traits play an important role in regulating ecosystem-level dynamics. We analyze responses of species attributes to diversity level and resource availability, and explore their consequences for ecosystem functioning and ultimately assess the contributions of five traits (vegetative plant height, clonal growth, root depth, cespitose habit and seed mass) to ecosystem functioning defined by spatial stability of community biomass. We found that functional traits disproportionately affected spatial stability. Relationships between species functional traits and spatial stability of community biomass indicated that diversity of vegetative plant height facilitated stability of a nitrogen fertilized undisturbed natural community (NAT), and that of a phosphorus fertilized forb, legume and bunchgrass community (FLB). The clonal growth form was also identified as a stabilizing trigger for a unfertilized undisturbed natural community (NAT), whereas diversity in root depth, cespitose habit and seed mass were related to destabilization of a nitrogen fertilized rhizomatous grass community (RRR). Studies quantifying interactions among plant traits, community structure and ecological functioning will contribute much more to understanding of the effects of the ecological behavior of specific traits on the ecosystem functioning.

3

Effect of long-term abandonment and spring grazing on floristic and functional composition of dry grasslands in a Central Apennine farmland

Catorci A., Cesaretti S., Gatti R.

Polish Journal of Ecology

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2013

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Vol. 61, nr 3

505--517

EN

Semi-natural dry grasslands host some of the most valuable habitats in Europe, due to their biodiversity heritage. Nevertheless, a strong decline in their extension, due to the cessation of traditional management, has been observed in the last decades. The aim of the study was to assess plant community changes due to abandonment and the effect of spring grazing in sub-Mediterranean dry grasslands, focusing on the plant functional traits involved in this turnover. The study area is located in the central Apennines (Italy), where grasslands were grazed by sheep in late winter and spring until 1980 and are nowadays abandoned. Relevés sampled (using the Braun-Blanquet method) in different years, namely in 1976–1980 (grazed pasture) and again in 2010 (abandoned pasture) were compared. Results indicated that abandonment leads to the increase of species richness. Traits and strategies indicator sets were: therophyte for the grazed pasture; geophytes, flower palatability, early flowering strategy, clonal ability and presence of storage organs for the abandoned ones. Traits related to low levels of stress (tolerance strategies) are heavily reduced in grazed systems, and thus the functional composition of plant community is mostly characterised by traits promoting avoidance strategies. In abandoned conditions a higher number of species can co-exist thanks to the micro-scale variation of soil features and niche diversification. The research findings also revealed grazing timing as a key factor for understanding changes of plant functional trait patterns and spring grazing as a threat for orchid species.