نتایج جستجو برای: urban basin

تعداد نتایج: 226881  

2017
Xibao Xu Guishan Yang Yan Tan Xuguang Tang Hong Jiang Xiaoxiang Sun Qianlai Zhuang Hengpeng Li

Land use changes play a major role in determining sources and sinks of carbon at regional and global scales. This study employs a modified Global biome model-biogeochemical cycle model to examine the changes in the spatiotemporal pattern of net ecosystem production (NEP) in the Taihu Lake Basin of China during 1985–2010 and the extent to which land use change impacted NEP. The model is calibrat...

1999
Gregory C. Johnson

• Median total phosphorus concentrations for the period 1984-93 were less than 0.1 milligrams per liter at 65 of the 83 stations evaluated in the study unit. • Highest total phosphorus concentrations were in the Hiwassee River Basin (near 2.0 milligrams per liter) and at West Chickamauga Creek near Chattanooga (1.45 milligrams per liter). • Total phosphorus concentrations have not significantly...

Journal: :Proceedings of the National Academy of Sciences of the United States of America 2002
Virginia P Edgcomb David T Kysela Andreas Teske Alvin de Vera Gomez Mitchell L Sogin

Molecular microbial ecology studies have revealed remarkable prokaryotic diversity in extreme hydrothermal marine environments. There are no comparable reports of culture-independent surveys of eukaryotic life in warm, anoxic marine sediments. By using sequence comparisons of PCR-amplified small subunit ribosomal RNAs, we characterized eukaryotic diversity in hydrothermal vent environments of G...

2017
Bart J. Harmsen Rebecca J. Foster Emma Sanchez Carmina E. Gutierrez-González Scott C. Silver Linde E. T. Ostro Marcella J. Kelly Elma Kay Howard Quigley

In this study, we estimate life history parameters and abundance for a protected jaguar population using camera-trap data from a 14-year monitoring program (2002-2015) in Belize, Central America. We investigated the dynamics of this jaguar population using 3,075 detection events of 105 individual adult jaguars. Using robust design open population models, we estimated apparent survival and tempo...

Journal: :Zootaxa 2014
Eduardo Hajdu Cristiana Castello-Branco

There are 22 species of Hamacantha registered from all over the world, and frequently from deep-waters, only two of which had previously been reported from the SW Atlantic. Here we describe a third species for this area, Hamacantha (H.) boomerang sp. nov., collected from deep-sea coral mounds at Campos Basin (off Rio de Janeiro state). We found oxeas 271-630 µm long, diancistras in three size c...

2003
A. H. ROY A. D. ROSEMOND J. B. WALLACE

1. The effects of catchment urbanisation on water quality were examined for 30 streams (stratified into 15, 50 and 100 km ± 25% catchments) in the Etowah River basin, Georgia, U.S.A. We examined relationships between land cover (implying cover and use) in these catchments (e.g. urban, forest and agriculture) and macroinvertebrate assemblage attributes using several previously published indices ...

2011
Juliane B Brown Lori A Sprague Jean A Dupree

SPAtially Referenced Regressions On Watershed attributes (SPARROW) models were used to relate instream nutrient loads to sources and factors influencing the transport of nutrients in the Missouri River Basin. Agricultural inputs from fertilizer and manure were the largest nutrient sources throughout a large part of the basin, although atmospheric and urban inputs were important sources in some ...

Journal: :Huan jing ke xue= Huanjing kexue 2012
Yan Wang Jun Li Xiang Liu Zhi-Neng Cheng Rui-Jie Zhang Gan Zhang

Atmospheric deposition of polychlorinated naphthalenes (PCNs) was investigated at 11 sites in Dongjiang River basin of Guangdong Province during the winter (January and February) and summer (July and August) of 2010 to assess the effect of PCNs on those areas. The average daily deposition fluxes of total PCNs was 828 pg x (m2 x d)(-1), and the corresponding TEQ was 0.14 pg x (m2 x d)(-1). Based...

2002
R. Ranzi M. Bochicchio B. Bacchi

River floods are influenced by factors such as the duration, intensity and spacial distribution of precipitation and the land-use as well as the morphological characteristics of the river basin. While the characteristics of the precipitation are tied to the climatology of the region and can change only over the long term, anthropogenic land use changes exhibit a more pronounced dynamic. However...

Journal: :Environmental management 2009
Carol E Rizkalla Robert K Swihart

Forest cover in the upper Wabash River basin in Indiana was fragmented due to agricultural conversion beginning more than 175 years ago. Currently, urban expansion is an important driver of land-use change in the basin. A land transformation model was applied to the basin to forecast land use from 2000 to 2020. We assessed the effect of this projected land-use change scenario on five forest rod...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید