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Role of Post-industrial Sites in Maintaining Species Diversity of Rare, Endangered and Protected Vascular Plant Species on the Example of the Urban-Industrial Landscapes
Published in Artur Dyczko, Andrzej M. Jagodziński, Gabriela Woźniak, Green Scenarios: Mining Industry Responses to Environmental Challenges of the Anthropocene Epoch, 2022
Barbara Bacler-Żbikowska, Teresa Nowak
The close relationship between biodiversity (including rare and protected species) and ecosystem functioning and ecosystem services has been proven. However, it is still poorly understood (Balvanera et al. 2016). Many authors accept that biodiversity is an ecosystem service itself, and many field studies provide supporting data (Balvanera et al. 2016; de Groot et al. 2016). It is very often difficult to estimate the role of individual species in providing specific ecosystem services (de Groot et al. 2016). Scientists undertake many projects regarding this problem. Species diversity plays an essential role in increasing resistance to invasive species and other disturbances (Wilsey & Polley 2002), which is extremely important in areas transformed by the human economy. Although seemingly most species seem superfluous, long-term studies show that high species diversity gives more excellent stability to the ecosystem, which leads to more significant and more stable provision of ecosystem services (Yachi & Loreau 1999).
Biodiversity: Tropical Agroforestry
Published in Yeqiao Wang, Terrestrial Ecosystems and Biodiversity, 2020
Sometimes thought of simply as the number of species in a given area, the concept of biodiversity is much more complex. In addition to a count of species, or species richness, it includes elements of species diversity, genetic diversity, functional diversity, and ecological diversity. Species diversity includes both the number of species in an area and the measure of their relative abundance or spatial distribution. For example, in Table 6.1, each of the two hypothetical communities has three species with a total of 100 individuals. The species richness is the same; however, as calculated by the Shannon Index,[16] the species diversity is higher in Community 2. As with most calculations of species diversity, the Shannon Index takes into account evenness, or a measure of the relative proportions represented by each species. Community 2 has a higher degree of evenness, and thus higher species diversity.
Marine Benthic Productivity
Published in Yeqiao Wang, Coastal and Marine Environments, 2020
Bayden D. Russell, Sean D. Connell
In conclusion, primary productivity in marine ecosystems is largely controlled by abiotic conditions such as resource availability. Human activities increase the availability of resources, changing the conditions for productivity and growth. The resulting increase in productivity does not affect different taxa uniformly, however, with fast-growing “weedy” species often benefiting more than the slower- growing species. The ensuing change in relative dominance, from slower-growing, habitat-forming species to simpler and fast-growing species, causes a loss of habitat and, subsequently, species diversity. In some cases, this ecosystem shift may be able to be reversed, such as by limiting the input of nutrient-rich wastewater into the sea. It remains to be seen, however, whether this will be possible as global CO2 emissions continue to increase, providing an almost unlimited source of carbon for enhanced primary productivity in the species of algae that maintain phase-shifts.
Potential risks of climate change and tropical storms on ecosystem and clams culture activities in Giao Thuy, Nam Dinh, Vietnam
Published in Human and Ecological Risk Assessment: An International Journal, 2023
Giang Pham Thai, Lua Dang Thi, Loan Vu Thi Kieu, Nguyet Nguyen Thi Minh, Thanh Pham Thi, Huy Tong Tran, Jeong Dae Seong, Han Kyungmin
Water Quality Index (WQI): WQI was calculated according to Vietnamese Ministry of Natural Resources and Environment guidelines. Parameters used for calculation include temperature, pH, Hg, Pb, Cd, As, P-PO4, N-NO2, and N-NH4. The rank consists of six grades: very good (91–100%), good (76–90%), fair (51–75%), bad (26–50%), and very bad (10–25%), polluted (0–10%). The allowable values of these parameters are shown in Table 1.Diversity index: The Shannon index (H') was used for the species diversity calculation. The index was calculated according to the following equations:
Floristic surveys of some lowlands polluted of a tropical urban area: the case of Yaounde, Cameroon
Published in International Journal of Phytoremediation, 2021
Ayo Anne, Soh Kengne Ebenezer, Djumyom Wafo Guy Valerie, Nbendah Pierre, Djomo Chimi Cédric, Nana Annie Stephanie, Djocgoué Pierre François, Kengne Noumsi Ives Magloire (In memorium)
In general, we observed that the most abundant macrophytes were not the most frequent on polluted sites also in the control site and vice versa. These results could be used to explain the differences in species diversity observed between polluted and control sites. Species diversity is an important index correlating the number of species and their distribution. Several authors say that the indicative value of a species depends on its overall relative frequency and abundance in sampling (Messou et al. 2013). However, abundant species can as well be characterized as tolerant to heavy metals in the tropical zone (Tchinda et al. 2018; Nguemte et al. 2018). Abundance being the best measure of the degree of tolerance for species growing in disturbed habitats. Thus, species that are very present and dominant in such areas should be those that have an adaptation strategy. According to Eid et al. (2020), heavy metal tolerance in plants is made possible through metal sequestration in plants tissues. This by production of organic compounds, compartmentalization in cell compartments, metal ion efflux, and organic ligand exudation. Such plants are referred to as “polluo-tolerant plant species” (Schwoertzig et al. 2016; Bonanno et al. 2017).
Use of local plants for ecological restoration and slope stability: a possible application in Yan’an, Loess Plateau, China
Published in Geomatics, Natural Hazards and Risk, 2019
Rui Xu, Xunchang Li, Wei Yang, Chao Jiang, Minou Rabiei
Because Artemisia spp. has a better adaptability to surrounding and its advantage will be more obvious with habitat destruction, Artemisia spp. accounts for about over half of all the plants if the slope is more than 40° (Figure 8). Therefore, Artemisia spp. is particularly suitable as pioneer plant for loess slope ecosystem reconstruction without special maintenance. However, the species diversity in an ecological community is beneficial to the ecosystem stability, sustainability, and rehabilitation (Figure 17). Besides Artemisia spp. without special maintenance, some selected plants, such as shrubs and herbs, should be sown and watered at the beginning of growth until their relatively longer roots ensure that they are able to extract water from depth, sustaining their growth. And if necessary, the engineering measures, such as geocell and drainage network, are suggested to ensure plants survival in high steep slopes.