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Pesticides and fertilisers contamination of groundwater
Published in Manish Kumar, Sanjeeb Mohapatra, Kishor Acharya, Contaminants of Emerging Concerns and Reigning Removal Technologies, 2022
Manish Yadav, Nitin Kumar Singh, Neeraj Kumar Singh, Tushali Jagwani, Suman Yadav
Agrochemicals adversely affect the bacterial population in the soil, which finally affects global ecosystem functioning. For the treatment of agrochemicals, earthworm plays a vital role in the treatment of soil. An earthworm belongs to Annelida phylum which has a tube-shape worm with segmented body. They have 7,000 species and one of the most important macrofauna of the soil. They can change physical, biological and chemical properties of soil, which makes them ecosystem engineer. They increase the nutrient content of the soil by degradation and mineralisation of organic matter. One of the major activities of earthworm, i.e. burrowing and casting activity, assists in recycling of nutrients in the soil to make them readily available to plants. Aeration and porosity are increased by the formation of burrows which finally promoted the growth of bacteria. Earthworms have the potential to store heavy metals in their body. This accumulation property of earthworm has taken attention of many researchers which later has proven as good remediation tool for the soil. All breakdown mechanisms take place in guts of earthworm. It has been found that polychlorinated biphenyl (PCB) and atrazine are degraded due to the presence of earthworm which shows that earthworms are capable of removing agrochemical contamination from soil (Singh et al., 2020).
Process-based approach on tidal inlet evolution – Part 1
Published in C. Marjolein Dohmen-Janssen, Suzanne J.M.H. Hulscher, River, Coastal and Estuarine Morphodynamics: RCEM 2007, 2019
D.M.P.K. Dissanayake, J.A. Roelvink
Organisms are however not always only passive subject to the abiotic environment. That is, by their behavior and/or merely their presence, several organisms are able to modify the abiotic conditions in their surroundings, and thereby able to reduce physical stress. These organisms that are able to significantly modify the abiotic environment are defined as ecosystem engineers (Jones et al., 1994, 1997; Reichman & Seabloom, 2002; Wright & Jones, 2006). In case they modify the environment via their actions, we call them allogenic ecosystem engineers (e.g., beavers), whereas species that modify their environment due to the presence of their physical structures are referred to as autogenic engineers (e.g., trees that make up a forest). Modification of the abiotic environment by ecosystem engineers appears to be particularly relevant in physically stressful environments (Jones et al., 1994, 1997). One of the reasons behind this observation is that habitat modification might be a suitable mechanism to reduce physical stress levels (e.g., see Bouma et al., 2005a).
Introduction
Published in Khalid Elnour Ali Hassaballah, Land Degradation in the Dinder and Rahad Basins, 2021
Another example describing the effects of ecological processes and patterns on hydrological regime refers to the so-called ecosystem engineers (Jones et al., 1994; Jones et al., 1997; Alper, 1998; Bruno, 2001; Crain and Bertness, 2006; Hastings et al., 2007; Wright, 2009; Jones et al., 2010). The terms “Ecosystem engineering” which refer to the process, and “Ecosystem engineers” which refer to the organisms responsible, were originally proposed by Jones et al. (1994). Ecosystem engineers defined as an organism that modify, maintain and/or create habitat. Ecosystem engineering leads to changes in two ways. First, through “autogenic engineering” in which the structure of the engineers itself alters the environment (e.g. tree growth) and the engineer remains as part of the engineered environment. Second, through “allogenic engineering” in which organisms transform habitats or resources from one physical state to another and the engineer is not necessarily part of the permanent physical ecosystem (e.g. beaver dams). Both animals and plants can be both autogenic and allogenic engineers (Jones et al., 1997). Such processes retain sediments and organic matter in the channel, influence the structure and dynamics of the riparian zone, change the characteristics of water and materials transported downstream, modify nutrient cycling and eventually influence plant and animal community composition and diversity” (Naiman et al., 1988). Understanding the ecosystem engineering processes required empirical data from comparative and experimental studies, models and conceptual integration of the processes (Jones et al., 1997), which are not available for the DNP. Thus, studying the ecosystem engineering process is beyond the scope of this research and is not part of our analysis.
What is the right scale? Encouraging fruitful engagement for ecology with ecohydraulics
Published in Journal of Ecohydraulics, 2018
Ecologists and ecohydraulicists and have long been captivated by the notion that the activities of organisms can bring about changes in the physical environment (Naiman 1988; Naiman et al. 1988). The well-cited paper by Jones et al. (1994) formally defined ecosystem engineers as organisms that modulate the availability of resources to other species by causing physical state changes in biotic or abiotic materials (i.e. resources) that are exploited by other species – and that this change in resources has ecological consequences, such as a change in species richness and composition. Thus, many ecosystem engineers are likely to create or modify physical heterogeneity and may be classified as biogeomorphic agents.
Worlding the end: A story of colonial and scientific anxieties over beavers' vitalities in the Castorcene
Published in Tapuya: Latin American Science, Technology and Society, 2021
Like humans or carps, beavers are classified as ecosystem engineers for their capacity to transform an ecosystem's entire structure and functions (Jones, Lawton, and Shachak 1994). In the world of eradication, beavers were apocalyptic creatures. The report translated the inundation that characterizes beaver's existential territories (Watson 2012) into an apocalypse. This riparian relation (Woelfle-Erskine 2017) derives from beavers' capacity to retain water and reduce river flows. Their interest in constructing dams has been interpreted as a means to secure their lodges from heavy currents or predators by generating swamps that are big enough to distance their lodges from the shore. The capacity to flood becomes vital power and a singular action from beaver's world-making. However, these vitalities are translated as the apocalyptic natures of the Anthropocene by conservation visions that see in the drowned and killed riparian forests of lenga trees, the image of the ruins of a failed fur industry from extractivist pasts (Figure 5). Captured by satellites, affective images of flooded forests circulated global anxieties of extinction. Among these translations is the potential destruction of a plant species. Beavers eat, chew, and cut Fuegian native trees, primarily lengas (Nothofagus pumilio), guindos (Nothofagus betuloides), and ñires (Nothofagus Antarctica). The lengas are the ones that beavers prefer; because lengas only regenerate through seeding, they take too much time to regenerate after flooding, the estimated regeneration time is a hundred years (Anderson et al. 2009). This particular characteristic of the relationship between beavers and lengas became a sign of potential extinction that circulated beyond TDF through global conservation actors.
Beetles (Insecta: Coleoptera) as bioindicators of the assessment of environmental pollution
Published in Human and Ecological Risk Assessment: An International Journal, 2018
Samir Ghannem, Samir Touaylia, Moncef Boumaiza
As reported by Rainio and Niemela (2003) bioindicators are considered effective tools for observing and monitoring changes in the environment. Lindenmayerr et al. (2000) defined the use of indicator species as an important and realistic tool for defining sustainable management to assess the effects of anthropogenic and natural disturbances in forests. Work et al. (2008) defined an indicator as any higher taxon or species sensitive to environmental changes. In addition, Siddig (2016) says that indicator species can be used in monitoring environmental changes, and provide warning signals for imminent ecological changes. Moreover, indicator species are living organisms that are easily controlled and whose arrangement reproduces or predicts the situation of the environment in which they are located (Bartell 2006; Burger 2006).The approach to employing indicator species is based on the hypothesis that environmental change may affect the abundance, diversity, and growth rate of one or more species in that location (Burrger 2006). Siddig et al. (2016) denoted that the concept of indicator species is related to several terms such as: (a) Indicator species: One or more taxa selected according to their sensitivity to a particular environmental factor, and then evaluated to make inferences about this factor. Eventually used in the concept of habitat management, restoration of ecosystems and wildlife conservation (Morrison 2009; Caro 2010); (b) Bioindicator/Biomonitor: One or more living organisms used as an indicator of the quality of the environment it is living in and the biological component associated with it. Bioindicators or biomonitors are mainly employed to monitor chemical changes in the environment in disciplines such as ecotoxicology (Burger 2006); (c) Umbrella species: Species that prefer large habitat areas, and are most often used for conservation applications and management of protected areas (Morrison 2009; Caro 2010); (d) Keystone species: due to strong interactions with other species, this species depends on the health condition of the ecosystem. They are used frequently for monitoring environmental quality, level of restoration and management of protected areas (Ellison et al.2005; Morrison 2009; Caro 2010); (e) Flagship species: A species that can, without difficulty, attract public support based on its charismatic qualities and state of conservation. Generally used to classify and monitor the conservation situation of the species (Morrison 2009; Caro 2010); (f) Ecosystem engineer: A species that controls the accessibility of resources for other species by creating physical changes in biotic or abiotic supplies. They are mainly used for ecosystem restoration and conservation (Morrison 2009); (g) Foundation species: A species that defines the structure of a community by ensuring the stability of local conditions for other species, the stabilization of basic ecosystem processes, and their role in controlling ecosystem changes (Ellison et al.2005).