A review of spatial causal inference methods for environmental and epidemiological applications

The scientific rigor and computational methods of causal inference have had great impacts on many disciplines, but have only recently begun to take hold in spatial applications. Spatial casual inference poses analytic challenges due to complex correlation structures and interference between the treatment at one location and the outcomes at others. In this paper, we review the current literature on spatial causal inference and identify areas of future work. We first discuss methods that exploit spatial structure to account for unmeasured confounding variables. We then discuss causal analysis in the presence of spatial interference including several common assumptions used to reduce the complexity of the interference patterns under consideration. These methods are extended to the spatiotemporal case where we compare and contrast the potential outcomes framework with Granger causality, and to geostatistical analyses involving spatial random fields of treatments and responses. The methods are introduced in the context of observational environmental and epidemiological studies, and are compared using both a simulation study and analysis of the effect of ambient air pollution on COVID-19 mortality rate. Code to implement many of the methods using the popular Bayesian software OpenBUGS is provided

Plastome phylogenomics of sugarcane and relatives confirms the segregation of the genus Tripidium (Poaceae: Andropogoneae)

Sugarcane (Saccharum officinarum) is one of the most important crops inthe world and a major source of sugar for human consumption. Despite this immense value, the circumscription of the genus Saccharum is complex, contentious, and largely unresolved. Saccharum is accepted in a broad sense by some authors or split into various genera such as Erianthus and Tripidium. A plastome phylogenomic analysis of sugarcane and relatives was performed in order to investigate generic delimitation, with emphasis on Tripidium (= Erianthus sect. Ripidium). Our plastome phylogenomics clearly demonstrates that Saccharum s.l. is polyphyletic and Tripidium (distributed in Old World) belongs to a distinct lineage from Saccharum s.s. (Old World) and Erianthus s.s. (= Erianthus sect. Erianthus, New World). Therefore, the present analysis confirms the recognition of Tripidium as a distinct genus from Saccharum and Erianthus, which is also supported by morphology and nuclear markers. The circumscription of Erianthus s.s. remains unclear since our plastome phylogenomics is consistent with either considering it as a distinct genus or including it in Saccharum. Better understanding of the evolutionary relationships of sugarcane and relatives may be useful for the selection of potential taxa for interspecific and intergeneric crosses in the genetic improvement of sugarcane. A taxonomic treatment of the six species of Tripidium is also presented, including descriptions, illustrations, data on geographical distribution, and three new nomenclatural combinations.Fil: Welker, Cassiano A. D.. Universidade Federal de Uberlândia; BrasilFil: McKain, Michael R.. University of Alabama at Birmingahm; Estados UnidosFil: Vorontsova, Maria S.. Royal Botanic Gardens; Reino UnidoFil: Peichoto, Myriam Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; ArgentinaFil: Kellogg, Elizabeth Anne. Donald Danforth Plant Science Center; Estados Unido