Raymon Shange

Background/Question/Methods Soil enzymes have been shown to be primary in the functional ecology of soil ecosystems. These enzymes have also been associated with the biogeochemical cycling of carbon, nitrogen, and phosphorous in the ecosphere at large. Because of the sensitivity of soil enzymes to changes in the environment, and their association with plant and microbial communities, their importance have been consistently suggested as ecological indicators within the soil system. This study utilized a survey methodology in which 45 samples were taken from three distinct land use types (pine plantation, grazed pasture, and cultivated vegetable crops) across one agricultural landscape. Soil organic carbon (SOC), pH, and phosphatase enzyme activities were measured and subjected to t-tests in order to determine significant differences between the means. Results/Conclusions Results show that the forested and grazed pasture areas were most distinctive in measured soil properties. In the ...

Background/Question/Methods Cyanide was first introduced commercially over a century ago, and since has been used or produced in many industries including: metal plating, gold mining, gas production, and pharmaceutical production. In the USA 10 million tons of road salt representing an environmental input of 700 tons of iron cyanide are used each year. The known problems with cyanide are its deleterious threats to both human and environmental health. The resiliency of certain communities may hold the key to cyanide remediation. The objective of this study is to evaluate the short term impact of cyanide treatment on soil microbial community composition and structure. A microcosm study was performed in which replicate soil microcosms were treated once with 2 different cyanide compounds (KCN and K2Ni(CN)4-2) and sampled over time for whole community DNA and subsequent 16S rRNA gene sequence analysis. Results/Conclusions Phyla that are commonly found in dominance in soils were also foun...

Two grazing experiments were performed to 1) investigate the effects of supplementing condensed tannins-containing pine bark powder on average daily gain, ruminal fermentation, and rumen microbial diversity dynamics (Experiment 1), and 2) to quantify the influence of different sources of extracted tannins supplementations on ruminal fermentation and rumen microbial diversity changes of goats grazing fresh forages (Experiment 2). In experiment 1, 20 Kiko-Boer cross male goats (Capra hircus; initial body weight= 39.7 ± 2.55 kg) were randomly assigned to 2 experimental diets (alfalfa pellet vs. pine bark powder). Alfalfa pellet (no tannin as a control) or pine bark powder (11% condensed tannins) was supplemented at 0.5% body weight for targeted total dry matter intake of 1.2% body weight. The remaining dry matter intake of each diet was obtained from grazing for 55 days. In experiment 2, 12 Kiko-Boer cross goats were used to measure average daily gain, ruminal fermentation, and gut mic...

Background/Question/Methods . Wetlands provide essential functions to the ecosphere that range from water filtration to flood control. These wetlands have also been reported to contain diverse assemblages of various organisms that greatly distinguish them from other ecosystems. During the 20th century about 53% of the nation’s original wetland acreage was destroyed as a result of agricultural and urban development. Current methods of evaluating the quality of wetlands include assessing vegetation, soil type, and period of inundation. Although these and other assessments have gained notoriety, some researchers have begun to question their efficacy in indicating ecological impact. Identifying sensitive indicators of ecological change that allow for the distinction of the unique ecosystems has become an important area in soil ecology. With recent advances in molecular and bioinformatic techniques, measurement of the structure and composition of soil bacterial communities has become an ...