Comparing connection to theory in Bachelor's theses: Old research university versus new regional university college

Quality of higher education is often assumed to be linked to the size of the faculty. Therefore, this study tested the hypothesis whether Bachelor's theses in ecology at a large, old research university would have more connection to theory than those at a small, young university college. The results revealed no significant difference between the universities. One potential explanation for these results is that theory is more likely to depend on the individual supervisor who may demand a clear connection to theory in Bachelor's theses. However, in the group of theses categorized as without a clear connection to theory, there were significant differences between the two universities regarding whether students were testing/developing a method or performing a case study. At the large, well-equipped research university, Bachelor's theses were significantly more likely to be based on developing/testing methods, while those at the university college more often comprised inexpensive case studies. Further studies including more universities of contrasting sizes, across countries and disciplines, are required to test the general validity of the findings.qscienc

Impacts of different climate change regimes and extreme climatic events on an alpine meadow community

Climate variability is expected to increase in future but there exist very few experimental studies that apply different warming regimes on plant communities over several years. We studied an alpine meadow community under three warming regimes over three years. Treatments consisted of (a) a constant level of warming with open-top chambers (ca. 1.9 °C above ambient), (b) yearly stepwise increases in warming (increases of ca. 1.0, 1.9 and 3.5 °C), and (c) pulse warming, a single first-year pulse event of warming (increase of ca. 3.5 °C). Pulse warming and stepwise warming was hypothesised to cause distinct first-year and third-year effects, respectively. We found support for both hypotheses; however, the responses varied among measurement levels (whole community, canopy, bottom layer, and plant functional groups), treatments, and time. Our study revealed complex responses of the alpine plant community to the different experimentally imposed climate warming regimes. Plant cover, height and biomass frequently responded distinctly to the constant level of warming, the stepwise increase in warming and the extreme pulse-warming event. Notably, we found that stepwise warming had an accumulating effect on biomass, the responses to the different warming regimes varied among functional groups, and the short-term perturbations had negative effect on species richness and diversityNFR grant (B-AA/BU 08424) to UM

Community and species-specific responses of plant traits to 23 years of experimental warming across subarctic tundra plant communities

To improve understanding of how global warming may affect competitive interactions among plants, information on the responses of plant functional traits across species to long-term warming is needed. Here we report the effect of 23 years of experimental warming on plant traits across four different alpine subarctic plant communities: tussock tundra, Dryas heath, dry heath and wet meadow. Open-top chambers (OTCs) were used to passively warm the vegetation by 1.5–3 °C. Changes in leaf width, leaf length and plant height of 22 vascular plant species were measured. Long-term warming significantly affected all plant traits. Overall, plant species were taller, with longer and wider leaves, compared with control plots, indicating an increase in biomass in warmed plots, with 13 species having significant increases in at least one trait and only three species having negative responses. The response varied among species and plant community in which the species was sampled, indicating community-warming interactions. Thus, plant trait responses are both species- and community-specific. Importantly, we show that there is likely to be great variation between plant species in their ability to maintain positive growth responses over the longer term, which might cause shifts in their relative competitive ability.Scopu

Temporal variations in ambient air quality indicators in Shanghai municipality, China

© 2020, The Author(s). Official data on daily PM2.5, PM10, SO2, NO2, CO, and maximum 8-h average O3 (O3_8h) concentrations from January 2015 to December 2018 were evaluated and air pollution status and dynamics in Shanghai municipality were examined. Factors affecting air quality, including meteorological factors and socio-economic indicators, were analyzed. The main findings were that: (1) Overall air quality status in Shanghai municipality has improved and number of days meeting ‘Chinese ambient air quality standards’ (CAAQS) Grade II has increased. (2) The most frequent major pollutant in Shanghai municipality is O3 (which exceeded the standard on 110 days in 2015, 84 days in 2016, 126 days in 2017, 113 days in 2018), followed by PM2.5 (120days in 2015, 104 days in 2016, 67 days in 2017, 61 days in 2018) and NO2 (50 days in 2015, 67 days in 2016, 79 days in 2017, 63 days in 2018). (3) PM2.5 pollution in winter and O3 pollution in summer are the main air quality challenges in Shanghai municipality. (4) Statistical analysis suggested that PM2.5, PM10, SO2 and NO2 concentrations were significantly negatively associated with precipitation (Prec) and atmosphere temperature (T) (p < 0.05), while the O3 concentration was significantly positively associated with Prec and T (p < 0.05). Lower accumulation of PM, SO2, NO2, and CO and more serious O3 pollution were revealed during months with higher temperature and more precipitation in Shanghai. The correlation between the socio-economic factors and the air pollutants suggest that further rigorous measures are needed to control PM2.5 and that further studies are needed to identify O3 formation mechanisms and control strategies. The results provide scientific insights into meteorological factors and socio-economic indicators influencing air pollution in Shanghai.This study was supported by the Key Research Program of Frontier Sciences (Grant No. ZDBS-LY-7011), National Key Research and Development Program of China (2017YFF0207303; 2016YFC0503004). The online sharing of air quality data by the Shanghai Environmental Monitoring Center is gratefully acknowledged

Severe vegetation degradation associated with different disturbance types in a poorly managed urban recreation destination in Iran

Recreational activities worldwide have major impacts on the environment. This study examined the impact of different kinds of recreational activities on plant communities in a highly visited park in Mashhad, Iran. Vegetation in the park was sampled along 41 random 10-m transects with different human disturbances (trails, dirt roads, campsites) and undisturbed communities. Life form spectrum, species composition, species and phylogenetic diversity were determined for all communities. Disturbance increased the frequency of therophytes, but decreased the frequency of chamaephytes and percentage vegetated area. Recreational-mediated disturbance had variable impact on species composition, but decreased species and phylogenetic diversity compared with undisturbed areas. Roads and campsites caused the greatest damage, while trails had the smallest negative impact on vegetation. This study showed that damage to (semi-)natural park vegetation differs with recreation activity. This finding can help prioritise management activities to minimise negative impacts of recreation activities on local vegetation. The current visitor load to the urban park studied here appears too high to be sustainable over time, so better monitoring and restrictions on visitor numbers may be needed to minimise the negative impacts on park vegetation. The camping impacts can be managed by creating clusters of designated campsites to spatially concentrate the impact area. Low-impact practices should be communicated to visitors.This work was fnancially supported by Iran National Science Foundation, INSF (grant number: 98026163

Quantification of ecosystem services providing socio-economic benefits to customary owners of natural resources in Pauri, western Himalaya

Climate change has negative consequences for the biophysical environment and an observable impact on flows of ecosystem services. Considering the high relevance of ecosystem services, it is imperative to analyze the present status of ecosystem services flows, for effective planning to cope with natural and anthropogenic catastrophes. It is equally important to identify drivers of natural resource deterioration. In a study conducted among 545 randomly selected households in 91 villages along an altitudinal gradient (1801 m asl (zone C)) in Pauri District, Uttarakhand, India, a multi-disciplinary bottom-up, indicator-based approach was applied for identification and normalization of indicators pertaining to ecosystem services. The greatest reduction in ecosystem services was recorded in zone A (0.56), followed by zone B (0.46) and C (0.35). The greatest estimated deterioration was seen in supportive (0.48) and regulatory (0.47) services. The perspective provided can facilitate adaptive management of ecosystems along an altitudinal gradient in the Himalayas, e.g., the district-level quantification of ecosystem services can guide policy-makers and planners towards more efficient adaptation planning and help minimize the gap between local requirements and policy/program formulation.The authors express their gratitude to the Hemvati Nandan Bahuguna Garhwal (A Central) University, Srinagar, Uttarakhand, India, for research assisstence. The authors thank editors Brian Fath and Bronwyn Hayward, and reviewers for constructive comments that improved the paper. JMA was funded by Qatar Petroleum (QUEX-CAS-QP-RD-18/19)

A Comprehensive Literature Review on Cadmium (Cd) Status in the Soil Environment and Its Immobilization by Biochar-Based Materials

Cadmium, Cd(II) pollution of soils is a serious environmental and agricultural issue, posing a threat to crop production, environmental quality, food safety, and human health. Therefore, immobilization of Cd(II) in soils is crucial. Biochar-based materials are receiving significant attention as Cd(II) immobilizers, due to their multifunctional surface properties. The remediation/immobilization mechanisms involved are, mainly, surface complexation, chemical reduction, precipitation, ion exchange, π–π interactions, hydrogen bonding, and adsorption. These mechanisms are mostly dependent on biochar surface pore size, oxygen-containing functional groups, pyrolysis temperature used in biochar preparation, biochar feedstock, and soil characteristics. So far, various pristine and modified biochar substrates have been used to remediate heavy metal-contaminated soils. Therefore, in this review paper, we briefly summarize the chemical forms, release sources, and maximum permissible limits of Cd(II) in soil. We also summarize recent scientific findings on the performance of biochar substrates in Cd(II)-contaminated soils to minimize Cd(II) mobility, bioavailability, and potential accumulation in crops. Finally, we identify challenges associated with the use of biochar and suggest areas for future research. The review presents an overview of the knowledge of biochar as a promising amendment for the decontamination of Cd(II)-polluted soils.J.M.A. was supported by Qatar Petroleum (QUEX-CAS-QP-RD-18/19)

Planning for assisted colonization of plants in a warming world

Assisted colonization is one way of facilitating range shifts for species that are restricted in their ability to move in response to climate change. Here we conceptualize and apply a new decision framework for modelling assisted colonization of plant species prior to in situ realization. Three questions were examined: a) Is species translocation useful in a certain area? b) where, and c) how long will it be successful in the future? Applying our framework to Carex foetida in Italy at the core of its distribution and its southern edge revealed that assisted colonization could be successful in short-term (2010–2039) climate conditions, partially in medium (2040–2069) but not in long-term (2070–2099) scenarios. We show that, for some species, it is likely that assisted colonization would be successful in some portions of the recipient site under current and short-term climate conditions, but over the mid- and long-term, climate changes will make species translocation unsuccessful. The proposed decision framework can help identify species that will need different conservation actions (seed banks and/or botanical gardens) when assisted colonization is unlikely to be successful. Furthermore it has broad applicability, as it can support planning of assisted migration in mountainous areas in the face of climate change.University of Pavia

Assessment of leaf morphological, physiological, chemical and stoichiometry functional traits for understanding the functioning of Himalayan temperate forest ecosystem

Leaf functional traits support plant survival and growth in different stress and disturbed conditions and respond according to leaf habit. The present study examined 13 leaf traits (3 morphological, 3 chemical, 5 physiological, and 2 stoichiometry) of nine dominant forest tree species (3 coniferous, 3 deciduous broad-leaved, 3 evergreen broad-leafed) to understand the varied response of leaf habits. The hypothesis was to test if functional traits of the conifers, deciduous and evergreen differ significantly in the temperate forest and to determine the applicability of leaf economic theory i.e., conservative vs. acquisitive resource investment, in the temperate Himalayan region. The attributes of the functional traits i.e., leaf area (LA), specific leaf area (SLA), leaf dry matter content (LDMC), leaf water content (LWC), stomatal conductance (Gs), and transpiration (E) followed the order deciduous > evergreen > coniferous. Leaf carbon and leaf C/N ratio showed the opposite pattern, coniferous > evergreen > deciduous. Chlorophyll (Chl) and photosynthetic rate (A) were highest for evergreen species, followed by deciduous and coniferous species. Also, structural equation modelling determined that morphological factors were negatively related to physiological and positively with chemical factors. Nevertheless, physiological and chemical factors were positively related to each other. The physiological traits were mainly regulated by stomatal conductance (Gs) however the morphological traits were determined by LDMC. Stoichiometry traits, such as leaf C/N, were found to be positively related to leaf carbon, and leaf N/P was found to be positively related to leaf nitrogen. The result of the leaf functional traits relationship would lead to precise prediction for the functionality of the temperate forest ecosystem at the regional scale