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Food Supply
Published in Cameron La Follette , Chris Maser, Sustainability and the Rights of Nature, 2017
Cameron La Follette , Chris Maser
A Rights of Nature system must integrate agriculture into the surrounding ecosystem. It must use and expand some version of the feudal chain of obligation discussed earlier in this book, with rights and obligations extended, in a web rather than a line, to the streams, woods, hedgerows (= naturally vegetated fencerow of woody and herbaceous plants), savannahs, and other aspects of the ecosystem integrated with a mosaic of small fields. Any functional agricultural system will, as indigenous Northwestern cultures have done for millennia, cultivate indicator species (such as huckleberries, salmon, herring, or clams) to both increase the food supply for humans and make the ecosystem more resilient, which is a benefit to all its inhabitants. An “indicator species” is an organism whose presence, absence, or abundance reflects a specific environmental condition. As such, the species’ abundance can indicate a change in the biophysical condition of a particular ecosystem, and thus may be used as a proxy to diagnose the system’s sustainability and its resulting productivity.
MABR process development downstream of a carbon redirection unit: opportunities and challenges in nitrogen removal processes
Published in Environmental Technology, 2022
Sadaf Mehrabi, Dwight Houweling, Martha Dagnew
The aerobic phylum of Nitrospirae grew in a significantly higher amount under continuous aeration rather than intermittent, which is consistent with the relative species abundance of Nitrospira sp as the most dominant species in R1 (Figure 6c). This finding contradicts the study by Bunse et al. that did not observe any difference in NOB abundance under intermittent vs continuous aeration [45]. The lower NOB relative abundance in intermittently aerated MABR was in agreement with previous works that reported decreased NOB growth rate and activity under intermittent aeration. The authors reported Nitrospira as the dominant NOB species rather than Nitrobacter, a typically most abundant species in continuous aeration systems [46, 47]. Similarly, another study indicated that in biofilm regions experiencing oxygen scarcity, Nitrospira was the dominant species, with a lower substrate utilization rate than Nitrobacter [48]. The observed lower NOB abundance in R3, the 3.7 OTR/removed NH4+-N ratio, and the removed COD/removed NOx-N of 3 were all indicators of a nitrite shunt process. Thus, the nitrogen removal in R3 could be through a nitrite shunt or autotrophic denitrification pathway.
Functional diversity and metabolic profile of microbial community of mine soils with different levels of chromium contamination
Published in International Journal of Environmental Health Research, 2020
Sukanta Kumar Pradhan, Upendra Kumar, Nihar Ranjan Singh, Hrudayanath Thatoi
Soil microorganisms are playing critical roles in the functioning of soil in nutrient cycling, structural formation and plant interactions, both positive and negative ways. The present study indicated that the chromium toxicity can significantly alter the soil environment by deteriorating some biological and physicochemical properties. The soil physicochemical properties, Shannon–Wiener and McIntosh indices, AWCD and heat map clustering analysis were significantly different between different studied soils, in particular between forest soil compared to chromite mine soils. The heavy metal toxicity has negative impact on soil AN, AP and AK as well as MBC and MBN affecting enzymatic activities in soils. The more species richness and less species abundance distribution (evenness) were observed in the chromium contaminated mining soils. The AWCD values also have negative correlation with the heavy metal concentration affecting the microbial metabolic activities. There is less utilization of carbon sources in chromite mine soils with the contamination of chromium. Contaminations of heavy metals in mine soil not only negatively affect the available essential nutrients but also decrease the microbial activity and alter their metabolic processes. The assessment of ecotoxicity and microbial activity would be an important step toward determination of environmental health and adoption of bioremediation program for their restoration.
Riparian health conditions of headwater streams in Southwestern Nigeria
Published in International Journal of River Basin Management, 2023
Olutoyin Adeola Fashae, Opeyemi Caleb Fatayo, Adeyemi Oludapo Olusola
The Shannon-Weiner Index (H`) weighs both species richness and species abundance (Shannon, 1948). It takes into account, the number of individuals as well as the number of taxa. It varies from 0 for communities with only a single taxon to high values for communities with many taxa, each with few individuals. It is expressed as: where H` = Shannon-Weiner diversity index, ni = number of individuals of a particular species, N = number of individuals of all species.