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Effects of channelization on Fish Biomass in River Ecosystems

Journal of Environmental Science and Engineering(A) 2012年第8期1卷 980-985页

作者： Scott S. Knight R.F. cullum F.D. Shields Jr. p.c. smiley USDA-ARS National Sedimentation Laboratory Oxford 38655 MS USA USDA-ARS-Soil Drainage Research Unit Columbus 43210 OH USA

channel straightening in a naturally meandering river is a common historical trigger of channel incision which typ.c.lly results in stream bank destabilization. Several of the larger river systems in the upland portion of the Yazoo River Basin have subjected channelization resulting in profound changes in the physical and geomorphological characteristics of these systems. Fish were sampled using electroshocking gear and hoop nets to evaluate the imp.c. of stream bank destabilization and loss of habitat heterogeneity resulting from channelization on fish communities. While distinct differences in the fish communities were evident, only the Skuna appeared to have characteristics of a damaged system. More than 95% of the biomass was comprised of sp.c.es reaching an adult length of less than 300 mm. The lotic omnivorous fishes that dominated the biomass from Skuna are often associated with smaller streams rather than rivers. Furthermore, 72% of the catch consisted of fish preferring littoral zone habitats. The shallow depth and lack of woody debris in Skuna provided a selective advantage for smaller sp.c.es of fish that could use shoreline habitats as protection from the current. Based on results from the Skuna River, channel straightening that leads to channel incision, bank failure and over widening provide habitats too shallow to support a community of fishes typ.c.l of northern Mississippi riverine system. This information may be useful in making comparison of damaged riverine ecosystems and assist managers in determining impairment and success in the TMDL （Total Maximum Daily Load） process.

关键词： channel incision channel straightening fish biomass.

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Short-Term Disturbance Effects of Outdoor Education Stream classes on Aquatic Macroinvertebrates

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Journal of Environmental protection 2017年第11期8卷 1333-1353页

作者： Jon p. Bossley peter c. smiley smiley Jr. Environmental Science Graduate program The Ohio State University Columbus OH USA School of Natural and Social Sciences Mount Vernon Nazarene University Mount Vernon OH USA USDA Agricultural Research Service Soil Drainage Research Unit Columbus OH USA

Outdoor education programs frequently offer stream classes that teach students how to assess water quality based on the composition of aquatic macroinvertebrate communities. Repeatedly using the same site for stream classes can cause disturbance that could negatively imp.c. aquatic macroinvertebrates. However, the imp.c. of outdoor education stream classes on short term temporal trends of aquatic macroinvertebrates has not been evaluated. Our objective was to quantify whether outdoor education stream classes caused localized and short-term imp.c.s on the aquatic macroinvertebrate community. We sampled aquatic macroinvertebrates over a five day period in May 2014 from an imp.c.ed riffle subjected to repeated substrate disturbance by outdoor education stream classes and an unimp.c.ed riffle that was not subjected to stream classes within an agricultural stream in central Ohio. We did not observe a difference in macroinvertebrate community response variables between different time periods or among days within the imp.c.ed riffle as part of our within riffle analysis. We documented that macroinvertebrate abundance and dorsoventrally flattened clinger abundance was greater within the unimp.c.ed riffle than the imp.c.ed riffle. Macroinvertebrate evenness was greater in the imp.c.ed riffle than the unimp.c.ed riffle. In the imp.c.ed riffle percent clingers was greater on Monday than on Friday. conversely, in the unimp.c.ed riffle percent clingers was greater on Friday than on Monday. Our results indicated that outdoor education stream classes did not alter short term temporal trends of macroinvertebrate community structure within an imp.c.ed riffle, but the stream classes resulted in differences in community structure between an imp.c.ed and unimp.c.ed riffle. Our results suggest that outdoor education centers should avoid repeatedly using the same site for their stream classes to prevent negatively imp.c.ing aquatic macroinvertebrates.

关键词： Substrate Disruption Trampling Macroinvertebrate community Riffles

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Small Mammal Habitat Use within Restored Riparian Habitats Adjacent to channelized Streams in Mississippi

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Journal of Environmental protection 2013年第11期4卷 1280-1291页

作者： peter c. smiley Jr. charles M. cooper USDA-ARS National Sedimentation Laboratory Oxford Mis- sissippi USA USDA-ARS Soil Drainage Research Unit Columbus Ohio USA

Riparian zones of channelized agricultural streams in northwestern Mississippi typ.c.lly consist of narrow vegetative corridors low in habitat diversity and lacking riparian wetlands. Land clearing practices and stream channelization have led to the development of gully erosion and further fragmentation of these degraded riparian zones. currently, installation of a gully erosion control structure (drop pipe) at the riparian zone-agricultural field interface leads to the incidental establishment of four riparian habitat types that differ in habitat area, vegetative structure, and pool size. Small mammals were sampled within four sites of each habitat type from June 1994 to July 1995. Small mammal diversity, abundance, and hispid cotton rat (Sigmodon hispidus) weight were the least within smallest Type I habitats with the least vegetative structural diversity and were the greatest within the larger Type II, III, or IV habitats having greater vegetative structural diversity and pool size. Small mammal diversity and abundance were the least in the summer 1994, increased in the fall 1994, and then declined later in our study. Hispid cotton rat abundance was the least in summer 1994, winter 1994, and spring 1995 and was the greatest in fall 1994 and summer 1995. Our results suggest that modifying the drop pipe installation design to facilitate the development of larger riparian habitats with greater vegetative structural diversity will provide the greatest benefits for small mammals.

关键词： Gully Erosion channelization channel Incision Erosion control Small Mammals

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化石DNA的发现及其地质背景和进化意义

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大自然探索 1991年第1期10卷 41-47页

作者：杨洪 c.J.smiley 洪光美国爱达荷大学地质系美国爱达荷大学地质系攻读博士学位

美国爱达荷(Idaho)州克拉克亚(clarkia)中新世木兰化石叶绿体 DNA 是目前人类所获取的最古老的基因密码。clarkia 产地独特的地质背景和古气候、古湖沼学条件构成了化石 DNA 保存的基础。化石的埋藏过程和埋藏条件是保持基因物质不被破... 详细信息

美国爱达荷(Idaho)州克拉克亚(clarkia)中新世木兰化石叶绿体 DNA 是目前人类所获取的最古老的基因密码。clarkia 产地独特的地质背景和古气候、古湖沼学条件构成了化石 DNA 保存的基础。化石的埋藏过程和埋藏条件是保持基因物质不被破坏的关键。化石 DNA 的研究将在修正进化率、认识成种作用、独立检验生物分类以及各种进化理论方面具有重大意义。

关键词：化石DNA 进化论埋藏学

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TyrB^(26)位点改变的人类胰岛素类似物的化学合成与体外活性

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中国生物工程杂志 2007年第7期27卷 40-44页

作者：马宝全康伟晏俊开 Vasily M Gelfanov David L smiley Richard D DiMarchi 南开大学生命科学学院天津300071 天津生物工程职业技术学院天津300462 美国印地安那州立大学化学系布卢明顿印地安那州47405

为了研究人类胰岛素B链第26位的酪氨酸对胰岛素和受体之间结合的影响,包括单独的氨基酸替换或化合物替换的不同胰岛素类似物的合成,其中化合物替代类似物的B链c末端都减少了4个氨基酸。在对它们与胰岛素受体的亲和力进行研究中发现它们... 详细信息

为了研究人类胰岛素B链第26位的酪氨酸对胰岛素和受体之间结合的影响,包括单独的氨基酸替换或化合物替换的不同胰岛素类似物的合成,其中化合物替代类似物的B链c末端都减少了4个氨基酸。在对它们与胰岛素受体的亲和力进行研究中发现它们与胰岛素受体的亲和力没有丢失,HisB26类似物和N-MeHisB26类似物的结合能力与胰岛素相比改变不大,分别是胰岛素的72%和107%。N-MeGluB26类似物,AadB26类似物和phe(4-carboxy)B26类似物的结合能力有很大的提高,分别是130%,234%和160%。

关键词：胰岛素胰岛素受体氨基酸

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