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The vegetation of the ecological substrate plays a crucial role in restoring shoreline ecology. This study focused on using zeolite and biochar as substrate modifiers, specifically utilizing the Cynodon dactylon from Central China for vegetation. A pot vegetation experiment was carried out to compare the effects of different ratios of zeolite and biochar. The vegetation indices, including germination index, plant height, and coverage rate, were analyzed and discussed. The results revealed that zeolite primarily influenced the germination index of Cynodon dactylon, while biochar had a more significant impact on germination percentage, germination energy, plant height, and coverage rate. This study discovered that the seed germination effect of the improved substrate initially increased with zeolite content and then decreased. The average germination percentage was 63.96%. Conversely, it decreased with an increase in biochar content, resulting in an average germination percentage of 55.45%. Zeolite and biochar caused a decrease and increase in substrate pH by −0.11 and 0.4 on average, respectively. The germination of each substrate showed a negative correlation with pH. Additionally, the average coverage and plant height decreased with an increase in biochar content. However, the inclusion of 6% zeolite led to an increase in coverage and plant height. Specifically, the average plant height increased by 3.92 cm and the coverage by 7.48%. Our research identified the optimal ratio of zeolite and biochar as 6% zeolite and 0% biochar, showcasing good overall vegetative properties. These findings offer insights for further understanding the vegetative effects of zeolite–biochar-modified substrates and optimizing substrate schemes for ecological vegetation projects. [ABSTRACT FROM AUTHOR]

The vegetation of the ecological substrate plays a crucial role in restoring shoreline ecology. This study focused on using zeolite and biochar as substrate modifiers, specifically utilizing the Cynodon dactylon from Central China for vegetation. A pot vegetation experiment was carried out to compare the effects of different ratios of zeolite and biochar. The vegetation indices, including germination index, plant height, and coverage rate, were analyzed and discussed. The results revealed that zeolite primarily influenced the germination index of Cynodon dactylon, while biochar had a more significant impact on germination percentage, germination energy, plant height, and coverage rate. This study discovered that the seed germination effect of the improved substrate initially increased with zeolite content and then decreased. The average germination percentage was 63.96%. Conversely, it decreased with an increase in biochar content, resulting in an average germination percentage of 55.45%. Zeolite and biochar caused a decrease and increase in substrate pH by −0.11 and 0.4 on average, respectively. The germination of each substrate showed a negative correlation with pH. Additionally, the average coverage and plant height decreased with an increase in biochar content. However, the inclusion of 6% zeolite led to an increase in coverage and plant height. Specifically, the average plant height increased by 3.92 cm and the coverage by 7.48%. Our research identified the optimal ratio of zeolite and biochar as 6% zeolite and 0% biochar, showcasing good overall vegetative properties. These findings offer insights for further understanding the vegetative effects of zeolite–biochar-modified substrates and optimizing substrate schemes for ecological vegetation projects.

Abstract Biological invasions are one of the major threats to biodiversity worldwide and contribute to changing community patterns and ecosystem processes. However, it is often not obvious whether an invader is the “driver” causing ecosystem changes or a “passenger” which is facilitated by previous ecosystem changes. Causality of the impact can be demonstrated by experimental removal of the invader or introduction into a native community. Using such an experimental approach, we tested whether the impact of the invasive plant Impatiens glandulifera on native vegetation is causal, and whether the impact is habitat‐dependent. We conducted a field study comparing invaded and uninvaded plots with plots from which I. glandulifera was removed and plots where I. glandulifera was planted within two riparian habitats, alder forests and meadows. A negative impact of planting I. glandulifera and a concurrent positive effect of removal on the native vegetation indicated a causal effect of I. glandulifera on total native biomass and growth of Urtica dioica. Species α‐diversity and composition were not affected by I. glandulifera manipulations. Thus, I. glandulifera had a causal but low effect on the native vegetation. The impact depended slightly on habitat as only the effect of I. glandulifera planting on total biomass was slightly stronger in alder forests than meadows. We suggest that I. glandulifera is a “back‐seat driver” of changes, which is facilitated by previous ecosystem changes but is also a driver of further changes. Small restrictions of growth of the planted I. glandulifera and general association of I. glandulifera with disturbances indicate characteristics of a back‐seat driver. For management of I. glandulifera populations, this requires habitat restoration along with removal of the invader.

Biological invasions are one of the major threats to biodiversity worldwide and contribute to changing community patterns and ecosystem processes. However, it is often not obvious whether an invader is the "driver" causing ecosystem changes or a "passenger" which is facilitated by previous ecosystem changes. Causality of the impact can be demonstrated by experimental removal of the invader or introduction into a native community. Using such an experimental approach, we tested whether the impact of the invasive plant Impatiens glandulifera on native vegetation is causal, and whether the impact is habitat‐dependent. We conducted a field study comparing invaded and uninvaded plots with plots from which I. glandulifera was removed and plots where I. glandulifera was planted within two riparian habitats, alder forests and meadows. A negative impact of planting I. glandulifera and a concurrent positive effect of removal on the native vegetation indicated a causal effect of I. glandulifera on total native biomass and growth of Urtica dioica. Species α‐diversity and composition were not affected by I. glandulifera manipulations. Thus, I. glandulifera had a causal but low effect on the native vegetation. The impact depended slightly on habitat as only the effect of I. glandulifera planting on total biomass was slightly stronger in alder forests than meadows. We suggest that I. glandulifera is a "back‐seat driver" of changes, which is facilitated by previous ecosystem changes but is also a driver of further changes. Small restrictions of growth of the planted I. glandulifera and general association of I. glandulifera with disturbances indicate characteristics of a back‐seat driver. For management of I. glandulifera populations, this requires habitat restoration along with removal of the invader. [ABSTRACT FROM AUTHOR]

Tropical and subtropical high-mountain forests are often restricted to ravines, with forest presence being rare in other topographies such as ridges. We tested the hypothesis that this distribution is partly due to increased soil water content and/or protection from winds in ravines as compared to ridges. We planted 396 saplings of the dominant tree species in a three-factor experiment that included topography (ridge/ravine), wind protection (protected/unprotected) and water addition (watered/not watered). We monitored wind speed and soil water content for one complete annual cycle and sapling survival and growth for 27 months. Sapling survival presented marginally significant differences for topography, being slightly greater in ridges than in ravines (0.88 and 0.78, respectively), with no significant differences for wind protection or water addition treatments. By contrast, sapling growth was considerably reduced in ridges as compared to ravines (16.1 and 26.0 cm, respectively); the wind protection treatment showed a significant positive effect on growth (saplings grew 25.5 and 16.5 cm with and without wind protection, respectively), whereas the water addition treatment had no effect. Importantly, saplings under wind protection treatment in ridges had similar growth to that of unprotected saplings in ravines, and growth difference due to the wind protection treatment was positively correlated with wind intensity, suggesting that reduced wind impact in ravines is an important abiotic factor that promotes forest occurrence in ravines. [ABSTRACT FROM AUTHOR]

Students often struggle to connect concepts with evidence, sometimes because development of research skills has not been emphasized in their science courses. We developed a strategy and protocol to train high school students in research and experimental investigation of questions related to course material on legume biology. The richness of this subject matter allows for adaptations of our framework to address diverse areas of science, including principles in ecology, environmental science, agriculture, microbiology, and evolution. Our framework includes a hands-on classroom inquiry that investigates the symbiotic relationship between nitrogen-fixing rhizobial bacteria and legumes. This student-led, inquiry-based project employs an intellectually demanding, hands-on method of education to build critical research skills using an adaptable model and inexpensive materials. We also report positive student feedback from a post hoc survey to gauge student attitudes toward the activity and the effectiveness of this framework. [ABSTRACT FROM AUTHOR]

• Planting seedlings under shrubs increased survival by 46 % after 3 years, with some marginal evidence that shrubs inhibited seedling diameter growth. • The addition of biochar increased seedling survival by 11% but had no effect on seedling growth. • Our study suggests that planted seedling survival in post-wildfire areas can be increased by utilizing existing vegetation and soil amended with biochar. The synergistic effects of widespread high-severity wildfire and anthropogenic climate change are driving large-scale vegetation conversion. In the southwestern United States, areas that were once dominated by conifer forests are now shrub- or grasslands after high-severity wildfire, an ecosystem conversion that could be permanent without human intervention. Yet, the reforestation of these landscapes is rarely successful, with a mean planted seedling survival of just 25 %. Given these low rates, we carried out a planting experiment to quantify the impacts of biochar as a soil amendment and shrubs as nurse plants on planted conifer seedling survival and growth following high-severity wildfire. We planted 1200 seedlings of three species (Pinus ponderosa , P. strobiformis , and Pseudotsuga menziesii) in a 2-ha area within the footprint of the Las Conchas fire in New Mexico, USA. We used four treatments: under shrubs, or in the open and with or without biochar in a full-factorial design. We found that planting tree seedlings underneath shrubs increased tree seedling survival by 46 % after 3 years, with some marginal evidence that shrubs inhibited seedling diameter growth (mean R2 = 0.08). The addition of biochar increased seedling survival by 11 % but had no effect on seedling growth. Our study suggests that planted seedling survival in post-wildfire areas can be increased by planting under shrubs in soil amended with biochar. The widespread adoption of these methods may improve the success rates of post-wildfire reforestation efforts in semi-arid areas, regaining some of the ecosystem services lost to high-severity wildfire. [ABSTRACT FROM AUTHOR]

The purpose of this study was to assess the volume increment diversification of selected provenances of grand fir growing under mountain conditions of Poland. The mean increment was determined on the basis of volume reached by the respective provenances when trees were 30 years old while the current increment was calculated from a difference between the volume when trees were 30 years old and the volume when they were 26 years old. It was found that the productive (increment) potential of tested grand fir partial populations is determined by the genotype (provenance). Among the tested provenances grand fir from Salmon River on Vancouver Island in Canada is characterized by the greatest productive capacity.

The genetic variation in 20 provenances of European larch, growing under site conditions of the Beskid Sądecki mountain range (experimental area in Krynica), was investigated during a long-term study carried out within the 1967 Polish Provenance Experiment on Larch. Data consisted of diameter measurements taken outside bark on standing trees of the analyzed provenances. Results showed that there was no distinct variation in the tested larch populations in respect of stem form. Some differences between compared provenances in respect of stem taper and form factor were the result of differences in tree height and diameter.

A long-term study carried out within the 1967 All-Poland Larch Provenance Experiment investigated genetic variation in 20 Polish provenances of larch growing under the site conditions of the Beskid Sądecki Mts. (at a test site in Krynica). The study was based on the measurements of tree height made in individual larch populations during 1969-1999, i.e. when trees were 5, 8, 11, 15, 20, 25, 30 and 35 years old. The results showed a considerable adaptation stability of the provenances tested at the Krynica site. This stability, however, tended to decrease with increasing mean height of trees. An estimation of the effect of the "genotype (provenance) × years of observation (age)" interaction revealed a high stability of height growth in larch populations having extreme values of this trait. As follows from the study, it is possible, especially in the case of the latter group of provenances, to carry out effective selection in the early stage of tree growth, thus ensuring a permanent genetic gain.

In this paper, two kinds of microbial agents - carbonate-microbe agents (CMA) and phosphate-microbe agents (PMA) - were used to remedy heavy metals in contaminated soil. Contrastive analysis of the remedying effects by CMA and PMA was obtained. Meanwhile, green vegetable cultivation and a vegetable transplanting experiment were conducted in contaminated soil that had been remedied by two kinds of microbial agents. The planting experiment clearly contributed to analysis of the remedying effect. The experimental results indicated that two kinds of microbial agents had a remarkable remedying effect on the heavy metals; the remedying effect of Cr2+ and Pb2+ by CMA was better compared with PMA, while the remedying effect of Cd2+ and Zn2+ by PMA was better than CMA, and the remedying effect of Cu2+ was almost equally good by two kinds of microbial agents. Bud rate and growth momentum improved significantly in contaminated soil after remediation, the concentration of heavy metals in seedlings and vegetables was reduced greatly, and several heavy metals indices were lower than the national standards. For different heavy metals pollution, different microbial agents should be used: namely the CMA are suitable for remedying Cr2+ and Pb2+, whereas PMA are suitable for remedying Cd2+ and Zn2+. [ABSTRACT FROM AUTHOR]