Where Did the Agricultural Nonpoint Source Trades Go? Lessons from Virginia Water Quality Trading Programs

Governmental agencies, nongovernmental organizations, and agricultural organizations promote water quality trading programs as an innovative policy to engage agricultural producers in conservation activities. Cost analyses suggest regulated sources can reduce compliance costs by purchasing agricultural nonpoint source credits. Yet, such “point‐nonpoint” trades are rare. This article assesses the demand for agricultural nonpoint sources in well‐developed nutrient trading programs in Virginia for industrial and municipal wastewater treatment plants, municipal stormwater programs, and land developers. Evidence suggests nutrient trading programs in Virginia will not stimulate investments in pollutant reduction practices on working agricultural lands. The lack of demand for agricultural nonpoint source credits can be attributed to a substantial degree to the design features and incentives present in multiple overlapping regulatory programs. The legal setting that dampens regulated source demand for nonpoint source credits in Virginia is broadly representative of conditions found elsewhere in the United States.     

中国露天生物质燃烧的温室气体排放及秸秆禁燃政策的协同减排效应

露天生物质燃烧是温室气体(CO₂、CH₄、N₂O)的重要排放源之一,这些排放可影响本地、区域和全球的大气化学和气候变化,并带来一系列生态环境问题,进而对人类及其他生物的生存环境产生影响.本研究采用卫星火点排放清单(FINN),对2010—2019年中国露天生物质燃烧温室气体排放进行研究,并分析秸秆禁燃政策对温室气体排放的影响,对后续秸秆禁燃政策的制定具有重要参考价值.结果表明,我国2010—2019年平均年温室气体排放量为1.53×10⁸t(将CH₄和N₂O的温室效应换算为同等效应的CO₂当量单位),总体呈波动性下降趋势.温室气体排放量最大的植被类型是森林(7.43×10⁷t)和农作物(3.19×10⁷t),分别占总排放量的48.7%和20.9%.从月分布来看,露天生物质燃烧排放的温室气体集中在2—6月,3月是高峰值.从空间分布上看,排放主要集中在华南、西南和华东地区,占总排放量的72.9%...     

Climatic, socio-economic, and health factors affecting human vulnerability to cholera in the Lake Victoria basin, East Africa

Cholera epidemics have a recorded history in the eastern Africa region dating to 1836. Cholera is now endemic in the Lake Victoria basin, a region with one of the poorest and fastest growing populations in the world. Analyses of precipitation, temperatures, and hydrological characteristics of selected stations in the Lake Victoria basin show that cholera epidemics are closely associated with El Ni?o years. Similarly, sustained temperatures high above normal (T(max)) in two consecutive seasons, followed by a slight cooling in the second season, trigger an outbreak of a cholera epidemic. The health and socioeconomic systems that the lake basin communities rely upon are not robust enough to cope with cholera outbreaks, thus rendering them vulnerable to the impact of climate variability and change. Collectively, this report argues that communities living around the Lake Victoria basin are vulnerable to climate-induced cholera that is aggravated by the low socioeconomic status and lack of an adequate health care system. In assessing the communities' adaptive capacity, the report concludes that persistent levels of poverty have made these communities vulnerable to cholera epidemics.     

PCDD/F and dioxin-like PCB in Hong Kong air in relation to their regional transport in the Pearl River Delta region

PCDD/F and dioxin-like PCB were measured in 142 air samples of Hong Kong. The annual average PCDD/F and dioxin-like PCB concentrations obtained for Hong Kong air at Tap Mun (PCDD/F: 1724+/-1984; dioxin-like PCB: 1572+/-1170 fg m(-3)), Yuen Long (PCDD/F: 2927+/-2695; dioxin-like PCB: 4331+/-1962 fg m(-3)) and Tsuen Wan (PCDD/F: 1875+/-1502; dioxin-like PCB: 2972+/-1510 fg m(-3)) from January 2004 to March 2005 were comparable to other urban centers around the world and were within the Japanese and USA ambient air quality guidelines. A clear seasonal pattern was observed for PCDD/F, generally with a 50-60 times higher air concentration in winter when background northerly wind was weaker and land-sea breeze prevailed, resulting in regional transport; and a lower concentration in summer, due to the inflow of clean oceanic southeasterly wind from the South China Sea. A higher WHO-TEQ value of dioxin-like PCB (mainly attributed to the relatively higher WHO-TEQ value of PCB 126) in Yuen Long during winter, compared with other months, could also be related to the regional transport by the winter monsoon wind and the low mixing height in winter. Spatially, air concentrations of PCDD/F and dioxin-like PCB demonstrated a west-to-east gradient (with Yuen Long>Tsuen Wan>Tap Mun). It is suggested that PCDD/F and dioxin-like PCB were transported into the western airshed of Hong Kong from the Pearl River Delta by land-sea breeze circulation and confined to the northwestern part, due to the blocking effect of the northwestern airshed in Hong Kong.     

Constant light exposure and/or pinealectomy increases susceptibility to trichloroethylene-induced hepatotoxicity and liver cancer in male mice

Environmental Science and Pollution Research - Exposure to light at night, pineal gland impairment, and the environmental pollutant trichloroethylene (TCE) have serious implications for health and...     

Connectivity of wood thrush breeding,wintering, and migration sites based on range‐wide tracking

Many migratory animals are experiencing rapid population declines, but migration data with the geographic scope and resolution to quantify the complex network of movements between breeding and nonbreeding regions are often lacking. Determining the most frequently used migration routes and nonbreeding regions for a species is critical for understanding population dynamics and making effective conservation decisions. We tracked the migration of individual Wood Thrushes (Hylocichla mustelina) (n = 102) from across their range with light‐level geolocators and, for the first time, quantified migration routes and wintering regions for distinct breeding populations. We identified regional and species‐level migratory connectivity networks for this declining songbird by combining our tracking results with range‐wide breeding abundance estimates and forest cover data. More than 50% of the species occupied the eastern wintering range (Honduras to Costa Rica), a region that includes only one‐third of all wintering habitat and that is undergoing intensive deforestation. We estimated that half of all Wood Thrushes in North America migrate south through Florida in fall, whereas in spring approximately 73% funnel northward through a narrow span along the central U.S. Gulf Coast (88–93°W). Identifying migratory networks is a critical step for conservation of songbirds and we demonstrated with Wood Thrushes how it can highlight conservation hotspots for regional populations and species as a whole. Conectividad de Sitios de Reproducción, Invierno y Migración del Zorzal con Base en Rastreo de Cobertura Amplia     

Hydraulic characterization for steam enhanced remediation conducted in fractured rock

To explore the viability of Steam Enhanced Remediation (SER) in fractured rock a small-scale steam injection and water/vapour extraction pilot study was conducted at the former Loring Air Force Base in northern Maine, USA. A detailed well testing program was undertaken to assist in the design of the injection and extraction well array, and to assess the possibility of off-site heat and contaminant migration. A structurally complex limestone having low matrix porosity and a sparse distribution of fractures underlies the study site. To characterize the groundwater and steam flow pathways, single-well slug tests and more than 100 pulse interference tests were conducted. The results of the well testing indicate that the study site is dominated by steeply dipping bedding plane fractures that are interconnected only between some wells in the injection/extraction array. The SER system was designed to take advantage of interconnected fractures located at depth in the eastern end of the site. An array of 29 wells located in an area of 60 by 40 m was used for steam injection and water/vapour extraction. The migration of heat was monitored in several wells using thermistor arrays having a 1.5 m vertical spacing. Temperature measurements obtained during and after the 3 month steam injection period showed that heat migration generally occurred along those fracture features identified by the pulse interference testing. Based on these results, it is concluded that the pulse interference tests were valuable in assisting with the design of the injection/extraction well geometry and in predicting the migration pathways of the hot water associated with the steam injection. The pulse interference test method should also prove useful in support of any other remedial method dependant on the fracture network for delivery of remedial fluid or extraction of contaminants.