Claytonfleming9598

Soil denitrifying enzyme activity (DEA) was measured by acetylene inhibition technique, along with exploration of factors influencing DEA in a bamboo forest riparian zone in the upper reaches of the Taihu Lake Basin during summer. Our aim was to provide important insights into the assessment of ecological functions of bamboo forest riparian zone on reducing nitrogen pollution in rivers. The results showed that the riparian soil DEA ranged from 6.32 to 23.22 μg N·kg-1·h-1, with a mean value of 14.65 μg N·kg-1·h-1. The vertical distribution (0-40 cm soil profile) of DEA was affected by several factors, such as soil organic carbon (SOC), total nitrogen (TN), nitrate nitrogen (NO3--N), soil water content, and activity of carbon and nitrogen hydrolase, which resulted in decreased DEA with increasing soil depth. The horizontal changes in DEA (at the same soil depth but at different distances from river) was mainly governed by the variation in SOC concentration. In this area, the concentration of soil dissolved organic carbon was relatively low, which might inhibit the soil DEA during summer.Based on the survey data from a 4 hm2 secondary Picea forest plot in the Pangquangou Nature Reserve, Guandi Mountain, Shanxi Province in 2010 and 2015, we analyzed the quantitative characteristics, distribution pattern, and correlation of living and dead standing trees during five years from four aspects, including species composition, diameter class structure, spatial pattern, spatial correlation between different diameter classes of living standing trees and dead standing trees, and intercorrelation between different diameter classes of dead standing trees. The results showed that there were 25811 living standing trees with DBH≥1 cm in the plot in 2010, belonging to 30 species, 22 genera, and 11 families. The distribution of individual diameter class was an inverted "L" type, and the number of individuals decreased in a fracture pattern with the increases of diameter class. During the five years (2010-2015), a total of 2145 dead standing trees were formed, involving 12 species, 10 genera, and 5 families. Moing trees, between 10 cm≤DBH less then 20 cm dead standing trees and 5 cm≤DBH less then 10 cm dead standing trees, and between DBH≥20 cm dead standing trees and 5 cm≤DBH less then 20 cm dead standing trees. Our results indicated that dead standing trees would impact the subsequent dying of living standing trees.Fine roots play an important role in energy flow and substance cycling in forests. How-ever, the estimates of biomass, production and turnover of fine roots remain large uncertainties, and the mechanism underlying local-scale spatial variation in fine roots is still unclear. In a temperate secondary forest in the Maoer Mountain in Northeast China, we investigated the vertical distribution of fine root biomass and necromass at the 0-100 cm profile and the dynamics, production and turnover rate of fine root in 0-20 cm soil layer. The sequential coring (including the Decision Matrix and the Maximum-Minimum formula) and the ingrowth core (3 cm diameter and 5 cm diameter) were compared in estimating production and turnover rate of fine roots. Forest stand variables that might affect fine roots were also explored. The results showed that 76.8% of fine root biomass and 62.9% of necromass concentrated in the 0-20 cm soil layer, and that both decreased exponentially with increa-sing soil depth. The seasonal variation in both fine root biomass and necromass was not significant in 0-20 cm soil layer, which might be related to the negligible snowfall in winter and the extremely high precipitation in summer. There was no significant difference in the results of the estimated fine root production between two diameter ingrowth cores. After log-transformed, fine root production and turnover rate estimated by the Decision Matrix, the Maximum-Minimum formula and ingrowth cores were significantly different among methods. With the increases of soil nutrient concentrations, fine root biomass/fine root necromass ratio significantly increased, fine root necromass significantly decreased, whereas fine root biomass, productivity, and turnover rate were not related to soil nutrient. There was a significant positive correlation between fine root production and aboveground woody biomass increment in the previous-year but not current-year.Understanding altitudinal variation characteristics and driving mechanism of soil enzyme activities and their stoichiometry is of great significance for studying nutrient cycling in fragile mountain forest ecosystems. In this study, we collected soil samples from different altitudes (1380-2438 m) in Helan Mountains to analyze the altitudinal changes in soil physicochemical properties, soil enzyme activities and their stoichiometry and its influencing factors. The results showed that the activities of β-glucosidase (βG) and β-N-acetylglucosaminidase (NAG) and the enzyme activities ratios of soil C/N and soil C/P firstly increased and then decreased with increasing altitude, which all peaked at 2139 m. Crenolanib solubility dmso Alkaline phosphatase (AKP) activities increased with the increases of altitude, with the maximum being found at 2438 m. However, L-leucine aminopeptidase (LAP) activities and soil N/P enzyme activities ratios did not change with increasing altitude. Compared with the soil enzyme stoichiometry in other regions of the world, Helan Mountains showed a certain degree of N limitation. Except for LAP, the activities of the other three enzymes were significantly positively correlated with the ratios of soil organic carbon/total nitrogen, soil organic carbon/total phosphorus, and total nitrogen/total phosphorus, and negatively correlated with pH. The LAP, soil C/P enzyme activities ratios and soil N/P enzyme activities ratios showed significant negative correlation with TP. In addition, AKP was significantly negatively correlated with soil bulk density.The development of contemporary macroecosystem sciences requires to comprehensively understand the process mechanism and model mechanism of large-scale macroecosystem structure and function, spatial variation, and dynamic evolution, to realize quantitative simulation, scientific assessment, prediction and early warning of ecosystem change and its impacts on human well-being, and to serve the utilization, protection, regulation, and management of ecosystems. Therefore, a new research field of large-scale integrated ecology of macroecosystem science (IEMES) is emerging. Based on the systematic analysis of the basic theories, approaches and key technologies of integrated ecology of macroecosystem science, the following basic understandings have been formed 1) IEMES takes macroecosystem at regional, continental, and global scales as the research object, and adopts the methods and technologies of multidisciplinary knowledge integration. It is aimed to solve the major resource and environmental problems during the ti-spatiotemporal ecosystem observation and experiment network is the basic scientific and technological facility to carry out deep integration of multi-disciplinary knowledge. It is necessary to develop key technology of multi-disciplinary ecological knowledge integration of multi-factor, multi-process, multi-interface, multi-medium, multi-scale, and multi-method around the regional, continental, and global scale macroecosystem science issues.The efficacy of immunotherapy for advanced non-small cell lung cancer (NSCLC) remains unsatisfactory, as the majority of patients either do not experience an objective response or acquire secondary resistance. As a result, several methods to enhance the systemic efficacy of immunotherapy have been investigated, including a large area of active research by combining immunotherapy with radiation therapy (RT). Given the rapidly burgeoning concept of combining immunotherapy and RT for increasing therapeutic benefit, we review the progress in this field thus far and explore further avenues for enhancing this combination. This review commences with a discussion of the only two existing randomized trials (and a pooled analysis) showing that the addition of RT to immunotherapy improves the abscopal response rate, progression-free survival, and overall survival in metastatic NSCLC patients. We then discussed factors and biomarkers that may be associated with a proportionally greater benefit to additional RT, such as low programmed cell death protein ligand 1 (PD-L1) status, tumor mutational burden (TMB), and patient's immune function. Next, the implementation of RT to overcome immunotherapy resistance is discussed, including a mechanistic discussion and methods with which these mechanisms could be exploited. Lastly, the emerging role of low-dose RT is discussed, which may help to overcome inhibitory signals in the tumor stroma that limit T-cell infiltration. Taken together, given the current state of this rapidly expanding realm, these futuristic strategies may be reflected upon to further enhance the efficacy of immunotherapy for a wider group of patients.This article explores how leadership education and program development is centered on the needs of students, local tribal communities, and institutional charter within the Tribal College and University (TCU) context. Two leadership-based academic programs at two respective TCUs are discussed through the lens of a culturally appropriate framework of Native-nation building to illustrate how leadership development at TCUs is focused on developing student leaders within and for tribal communities.This article focuses on the history of leadership education and student leadership development at Historically Black Colleges and Universities (HBCUs). Although HBCUs range in size and scope, the positive impact that HBCUs have had on graduates and the community large writ is unprecedented especially for students, faculty, administrators and staff of African descent.According to the Hispanic Association of Colleges and Universities, Hispanic Serving Institutions (HSIs) are defined as colleges, universities, or system/districts where total Hispanic enrollment constitutes a minimum of 25% of the total enrollment. Due to the enrollment dependent nature of HSIs, an institution's designation may change over time. This article will include a discussion of how HSIs develop campus cultures that go beyond their designation to support the leader development of students.This article describes the rationale given by many faith-based institutions of higher education for creating and promoting leadership programs. A brief overview of the history of faith based educational institutions is followed by an explanation of the motivations of several different schools for creating and funding leadership programs, as well as the limitations of those programs. The article concludes with suggestions for how these programs can benefit more students and the wider community.This article examines higher education as a vehicle for leadership development and discusses the historical evolution of different institutional types. Through the lens of access and equity, the traditional leadership narrative can expand to critically examine how these different institutional types advance racial equity in leadership education.