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This paper presents a unified framework for transmission-disequilibrium tests for discrete and continuous traits. A conditional score test is derived that maximizes power to detect small effects for any exponential family distribution, which includes binary and normal distributions, and distributions that are skewed or have non-normal kurtosis. The specific distributional form need not be specified, and the method applies to sibships of arbitrary size. Formulas for the distribution of the test statistic are given for models including complex genetic effects (additive, dominant, and recessive gene action), covariates, multiple gene models including gene-gene interactions or heterogeneity, and gene-environment interactions. We develop refinements of our method for trait-based sampling designs and multiple siblings that can have dramatic effects on power.

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Open-pit coal mine dumps in semi-arid areas in northern China are affected by serious soil erosion problems. The conventional field investigation method cannot ensure a fine spatial analysis of gully erosion. With recent technological and algorithmic developments in high-resolution terrain measurement, Unmanned Aerial Vehicles (UAVs) and Structure from Motion (SfM) technology have become powerful tools to capture high-resolution terrain data. In this study, two UAV Photogrammetry surveys and modeling were performed at one opencast coal mine dump gully before and after a freeze-thaw cycle. Finally, a three-dimensional digital model of the slope of the drainage field was established, and a centimeter-level-resolution Digital Orthophoto Map (DOM) and a Digital Elevation Model (DEM) were created. Moreover, the development process of the erosion zone of the open-pit mine dump during a freeze-thaw cycle was studied by UAVs. The results show that there are clear soil erosion phenomena in the erosion gully of the dump during a freeze-thaw cycle. The erosion degree was different across regions, with the highest erosion occurring in high-slope areas at the upper edge of the bank. Moreover, the phenomenon of flake erosion and “crumble” was recorded. At the same time, the NE-E-SE slope and the high-sunshine radiation zone were seriously eroded. Finally, the relationship between the development process of the erosion gully and micro-topography factors was analyzed, providing managers with a sound scientific basis to implement land restoration.

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To understand the response of soil microbial communities in different types of wetlands to anthropogenic disturbances, this study focused on a freshwater wetland (Sanjiang Wetland) and a salt marsh (Momoge Wetland) and sampled cultivated, degraded, and natural soils in these wetlands. High-throughput sequencing was applied to characterize the soil microbial community composition, and physicochemical properties, including pH, total nitrogen, total carbon, and soil water content (SWC), were measured. The results revealed that the total nitrogen, total carbon, and SWC were significantly lower in disturbed soil in the freshwater wetland but higher in the salt marsh. Generally, under anthropogenic disturbances, microbial community diversity decreased in the freshwater wetland and increased in the salt marsh. The bacterial community structure in the salt marsh was more sensitive than that in the freshwater wetland, while the fungal community structure in the freshwater wetland was more susceptible than that in the salt marsh. The results of indicator value analyses revealed specific issues in two wetlands, such as methane generation and anoxic conditions. This study shows that soil microbiomes in two types of wetlands respond differently to human activities, which implies that the type of native wetlands should be considered in the exploitation of wetlands.

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