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Changes in Soil Phosphorus Fractions Following the Conversion of Chinese Fir Plantations to Evergreen Broad-leaved Forests in Subtropical China
No full textForest conversion is a common management practice in forestry, yet the effects of forest conversion on the transformation of phosphorus (P) fractions remain unclear. This work aims at assessing the changes in soil P fractions, including total P (TP), available P (AP), inorganic P (Pi), organic P (Po) and microbial biomass P (MBP) after natural conversion of Chinese fir plantations (CFP) to evergreen broad-leaved forests (EBLF) in subtropical China. Results showed the contents of soil TP and Po were not affected by the forest conversion, but soil AP and MBP concentrations and their proportion significantly increased with forest conversion from CFP to EBLF. The contents of soil P fractions were significantly accumulated in the topsoil (0–20 cm) in the studied forests. Additionally, soil P contents were higher in the winter–spring seasons than in the summer–fall seasons during the period of study. Soil AP content was positively correlated with TP, Po, Pi, labile organophosphorus (LOP), moderate labile organophosphorus (MLOP), moderate resistant organophosphorus (MROP), aluminum–bound P (Al–P), iron–bound P (Fe–P) and MBP contents in EBLF, while the content of soil AP was positively related to Po, LOP, MLOP, Al–P, Fe–P and MBP contents in CFP. Path analysis showed that the most important factor in affecting soil P availability was Po (LOP and HROP) in EBLF stands and was Al–P in CFP stands. Our study suggested that management practices in conserving soil Pi (especially in Al–P) in the CFP and in increasing Po inputs in the EBLF would improve soil P availability in subtropical forests.https://opus.govst.edu/fac/1183/thumbnail.jp
Characterization and Application of Fe-modified Biochar Alleviating Cr(VI) Stress in Pak Choi Seedling Cultivated in Cr-polluted Hydroponics
No full textChromium (Cr) is one of the common environmental pollutants, which causes severe health hazards on human health and environmental security. In this study, we characterized two biochars, a raw biochar (RBC) and a Fe-modified biochar (MBC) made from poplar wood chips and determined the effect of the two biochars on remediation of hexavalent chromium (Cr(VI)) in hydroponic system by monitoring Pak choi growth. Results showed the surface area, pore number and pore volume were significantly higher in MBC than in PBC, but the pore size was larger in PBC than in MBC. When compared to the control, low concentrations of Cr(VI) (≤2 mg L−1) promoted the growth and biomass production of Pak choi by 10–78%. In contrast, the high concentrations of Cr(VI) (≥4 mg L−1) showed a significantly reduction of the growth and biomass production of Pak choi by 10–28%. Fe-modified biochar (MBC) had a more significant impact than RBC on the remediation of Cr in the Cr(VI) pollution and improved growth and biomass production of Pak choi to a greater extent. Our study indicated that MBC has a better effect on degrading Cr(VI) pollution. The findings provide scientific basis and reference for the remediation of heavy metals in aquatic ecosystems by using biochar.https://opus.govst.edu/fac/1180/thumbnail.jp
Ecological Stoichiometry and Stock Distribution of C, N, and P in Three Forest Types in a Karst Region of China
No full textEcological stoichiometry plays important roles in understanding the nutrient constraints on tree growth and development, as well in maintaining ecosystem services in forests, yet the characteristics of carbon:nitrogen:phosphorous (C:N:P) stoichiometry in forests under karst environment have not been sufficiently evaluated. In this study, concentration, distribution, stocks of Nitrogen (N) and Phosphorous (P), and ecological stoichiometry were studied in three common forest types: Masson pine natural forests (MPNF), Masson pine plantation forests (MPPF), and Slash pine plantation forests (SPPF) in a karst region of southwestern China. Results showed that N concentrations were higher in overstory than in understory and litter in the studied forests. However, P concentration was relatively low in overstory component of the forested ecosystems. Meanwhile, the N and P concentrations were higher in SPPF in the stem and litter, while these contents were higher in MPPF and MPNP in the overstory and understory. The N and P stocks ranged from 5.7–6.2 t ha−1, and 0.5–0.6 t ha−1 in the examined forests. The ecological stoichiometry of C:N:P in the three forest types was similar in litter (46–49:2:1), and relatively steady in soil (250–320:13–16:1) and tree leaf (100–200:14–20:1). Soil P status was the primary limiting factor in affecting tree growth in MPPF and SPPF (N:P ratio \u3e 16), while both N and P conditions were the main restrictive factors in MPNP (N:P ratio = 15) in the study area. Our study provides scientific references and useful datasets of C:N:P stoichiometry for sustainable management of forest ecosystems in karst regions.https://opus.govst.edu/fac/1178/thumbnail.jp
Legume Biological Nitrogen Fixation Improves but Chemical Nitrogen Fertilizer Suppresses Soil Nematode Communities in a Camellia Oleifera Plantation
No full textLegume intercropping by biological nitrogen (N) fixation is supposed as a more sustainable way than chemical N addition to enhance soil N availability in agronomy, however, the effects of the two types of N input on soil food web are scarcely determined. To fill the knowledge gap, we conducted a field experiment with randomized block design in an oil-tea (Camellia oleifera) plantation, which included five N manipulation treatment: legume intercropping (Arachis hypogaea and Cassia tora), chemical N fertilizer application (84 and 168 kg N ha-1 yr-1), and the control (no N addition). The soil nematode communities and physicochemical properties were monitored in the seedling, heading, and mature stages of the legumes respectively. The results showed that the legume intercropping significantly increased the abundances of bacterivores and omnivore-predators compared with the N fertilizations. Weighted nematode fauna analysis showed that N fertilization treatments were mainly located in the degraded plot (quadrat IV), and legume treatments were located in the structure plot (quadrat III). Structural equation model revealed that the legume intercropping positively correlated with the abundance of bacterivores and omnivore-predators while N fertilization rate negatively correlated with the abundance of bacterivores and fungivores. Our results suggest that the legume biological N fixation was more conducive to providing N sources to soil organisms than the chemical N fertilizer, which resulted in an enhanced and a degraded soil food web respectively. Thus, legume intercropping is a more sustainable N management practice for the cultivation of C. oleifera plantations.https://opus.govst.edu/fac/1173/thumbnail.jp
Synthesis and Scope of the Role of Postmating Prezygotic Isolation in Speciation
No full textHow barriers to gene flow arise and are maintained are key questions in evolutionary biology. Speciation research has mainly focused on barriers that occur either before mating or after zygote formation. In comparison, postmating prezygotic (PMPZ) isolation—a barrier that acts after gamete release but before zygote formation—is less frequently investigated but may hold a unique role in generating biodiversity. Here we discuss the distinctive features of PMPZ isolation, including the primary drivers and molecular mechanisms underpinning PMPZ isolation. We then present the first comprehensive survey of PMPZ isolation research, revealing that it is a widespread form of prezygotic isolation across eukaryotes. The survey also exposes obstacles in studying PMPZ isolation, in part attributable to the challenges involved in directly measuring PMPZ isolation and uncovering its causal mechanisms. Finally, we identify outstanding knowledge gaps and provide recommendations for improving future research on PMPZ isolation. This will allow us to better understand the nature of this often-neglected reproductive barrier and its contribution to speciation.https://opus.govst.edu/fac/1121/thumbnail.jp
What We Owe Owls. Nonideal Relationality among Fellow Creatures in the Old Growth Forest
No full textThough many of us have constructed our lives (or have had them constructed for us) such that it is easy to ignore or forget, human lives are entangled with other animals in many ways. Some interspecies relations would arguably exist in some form or another even under an ideal model of animal ethics. Others have an inescapably non-ideal character – these relationships exist as they do because things have gone wrong. In such circumstances we have reparative duties to animals we have wronged because we have wronged them. Here I draw upon Christine Korsgaard’s “Fellow Creatures” (2018) and other nonideal approaches to animal ethics to critically assess the United States Fish & Wildlife Service practice of killing barred owls to protect endangered spotted owls in the old growth forest of the Pacific Northwest. This is a difficult case to be sure, but one that can benefit from non-ideal moral assessment in terms of interspecies relational repair. I argue for increased spotted owl habitat preservation and forest restoration as an alternative to barred owl removal that better aligns with both nonideal relational animal ethics and stated US Fish & Wildlife Service values.https://opus.govst.edu/fac/1104/thumbnail.jp
Leguminous Crop Restores the Carbon Flow Attenuation from Nitrogen Loading Within Woil Nematode Food Web in a Camellia oleifera Plantation
No full textExcessive nitrogen (N) loading poses a substantial risk to soil biodiversity and disrupts carbon (C) flows within the soil food web. Intercropping with legumes is often considered a sustainable way to maintain soil N availability and mitigate the associated detrimental effects. However, it remains unclear whether and how legume crops restore energetic attenuation caused by N loading within the soil food web. Here, we conducted a two-year field experiment using randomized block design in a subtropic Camellia oleifera plantation with high wet N deposition. We examined the effects of applying N fertilizers at normal or half levels (168 or 84 kg N ha−1yr−1) and intercropping legumes (Arachis hypogaea or Cassia tora) on the soil nematode food web. We observed that N fertilization suppressed the majority of nematode trophic groups, weakened the stability of food web structure, and diminished the C flows across the bacterial and fungal energy channels. Conversely, intercropping with legumes (particularly with C. tora) bolstered the densities of bacterivore and fungivore nematodes. This enhancement facilitated interactions within the soil micro-food web, and subsequently augmented the C flows within their respective channels. Model predictions suggested that the detrimental effects of N fertilizers on the nematode food web are primarily linked to decreased soil pH resulting from soil N accumulation. Notably, higher soil organic C was found to mitigate these effects. Furthermore, N-enriched legume substrates played a beneficial role in stimulating soil microbial activities and facilitating C flows through bottom-up control. Our findings emphasize the positive impacts of legume crops on mitigating soil biodiversity loss and restoring energetic attenuation within soil food web under N-saturated soil conditions. These findings provide valuable insights for agroforestry management practices aimed at sustaining soil health and ecosystem resilience.https://opus.govst.edu/fac/1067/thumbnail.jp
Evaluating the Effectiveness of Cyber Security Regulations
Get PDFThe rapid advancement of technology has led to an increase in the volume and sensitivity of personal and professional data stored and shared online. As a result, there is a growing need for effective cyber security regulations to protect against data breaches and ensure the confidentiality and integrity of sensitive information. The Health Insurance Portability and Accountability Act (HIPAA), Payment Card Industry Data Security Standard (PCI DSS), and General Data Protection Regulation (GDPR) are three such regulations that have been implemented to address this need. This thesis aims to evaluate the effectiveness of these regulations in protecting sensitive information and preventing data breaches. A comprehensive literature review of existing research on the topic is conducted, and case studies of the implementation and enforcement of these regulations are analyzed. The study finds that while these regulations have been successful in raising awareness and establishing standards for cyber security, there is still room for improvement in their implementation and enforcement. Additionally, the study identifies the challenges and limitations in evaluating the effectiveness of cyber security regulations. Finally, recommendations for future research are provided in this area. The study concludes that while these regulations are important steps towards improving cyber security, more research is needed to fully understand their effectiveness and potential for improvement
2023-2024 Catalog
Get PDFThe 2023-2024 Governors State University Undergraduate and Graduate Catalog is a comprehensive listing of current information regarding:Degree RequirementsCourse OfferingsUndergraduate and Graduate Rules and Regulation
Flawed Feminism: An Exploration of Femininity in Contemporary Domestic Noir
Get PDFCrime fiction is a genre whose female characters are often misunderstood, weak, powerless victims. Domestic noir, a subgenre of crime fiction, does the opposite. Authors of domestic noir fiction dig into the female experiences, seeking to understand and write women characters who represent feminism and femininity despite any shortcomings they have. In Big Little Lies by Liane Moriarty, I argue that reading this novel through the Critical Feminist Theory changes the interpretation of the female experience. Instead of reading the book for entertainment, digging into the larger scale issues in this book sheds light on the women’s experiences. Gone Girl by Gillian Flynn is another novel misunderstood through the female main character. I argue that Amy’s villainy doesn’t make her any less feminine even though she is a psychopath. Often compared to Gone Girl, The Girl on the Train by Paula Hawkins is focused in this thesis as its own entity. In contrast to Big Little Lies’ female main characters, Hawkins explores three female main characters who are not so privileged, who do not exude feminism, women who make mistakes in which there is no coming back from, and women who have loved too much or have been loved too little; all of whom emulate feminism in their individuality