四川绵阳市三江库区水鸟类资源及保护对策

1998年9月～2001年12月,对绵阳市三江库区水鸟资源进行了调查,共观察到水鸟49种,隶属10科7目,占四川水鸟种数的39.8%,占全国水鸟种数的22.68%.同时就库区鸟类保护提出几点建议.     

长洲水利枢纽建坝后对库区水鸟影响的预测分析

长洲水利枢纽库区分布有41种水鸟,其中38种是涉禽,它们主要栖息于河谷带。环境影响评价分析表明,大坝建成蓄水后将给涉禽带来很不利的影响。由于生境的改变,库区水鸟群落将发生变化,涉禽的种类和数量将减少,而游禽的种类和数量将增多。建议开展受威胁的珍稀水鸟海南鳽(Gorsachius magnificus)的生态生物学研究,以便提出有效的保护措施。     

四川绵阳地区水鸟的多样性分析

2000年1月～2003年1月,采用样线法对绵阳地区水鸟进行调查,共记录7目10科30属58种。其中有各级保护动物19种,留鸟12种(20．7％),夏候鸟4种(6．92％),旅鸟、冬候鸟各21种(36．19％)。区系组成包括：古北型43种(74．1％),东洋型9种(15．5％),广布型6种(10．4％)。多样性分析得出绵阳地区水鸟Shannon-Winer指数H’=2．5736、Pielou指数J=0．6338及G-F指数DG-F=0．5936。在3种不同类型湿地生以涪江境中,河谷多样性最丰富。同时指出,自然环境恶化和人类活动是该地区水鸟面临的主要威胁。     

鸭绿江河口水鸟调查报告

１９９７年３月至１９９８年４月,在鸭绿江河口中国一侧进行的鸟类调查中,共录得水鸟８３种,隶属于６目１０科３８属。其中６８种（８１．９％）被敖中日候鸟保护协定,国家Ⅱ级保护水鸟４种,世界濒危水鸟１种;繁殖水鸟２８种,冬侯卵９种。克季迁徙主食昆虫高峰期为５月９日,秋季为８月１１日。在鸭绿江下游发现大的鹭类繁殖群。     

山东聊城水鸟组成及其生态分布

报道了聊城境内水鸟种类及其1991—2000年间的分布变动。结果显示,聊城境内有水鸟7目12科45种．绿头鸭、斑嘴鸭为优势种;常见种有小鹏鹏、苍鹭、普通秋沙鸭、白腰草鹬及普通翠鸟;珍稀鸟类包括东方白鹳、白琵鹭、大天鹅、中华秋沙鸭、黑尾塍鹬及黑嘴鸥等6种。本地区80％的水鸟数量趋于下降,应加强保护工作。     

密云水库的浮游植物群落结构与密度

 1998年的调查研究显示,密云水库库区水体的浮游植物群落为硅藻(Bacillariophyta)—绿藻(Chlorophyta)型,细胞密度为358.76×104·L-1。湖泊的营养特征为浮游植物响应型。1988～1998年库区水体总氮增长48.7％,总磷增长31.2％,浮游植物细胞密度增长41.7％,库区水体已为中营养,并出现了富营养型浮游植物指示种类,例如斜生栅藻(Scenedesmus obliquus(Turp)．Kütz．),铜绿微囊藻(Microcystis aeruginosa Kütz．),湖泊色球藻(Chroococcus limneticus Lemm．)。水体向富营养化发展趋势明显。应加强水环境保护,增加密云水库流域植被覆盖度,净化、涵养水源,以保证密云水库向北京市供水的质量和数量。     

三门峡黄河库区湿地自然保护区鸟类区系调查

１９９５－１９９７年对河南省三门峡黄河库区湿地自然保护区鸟类资源进行了调查,共记录鸟类７８种,隶属１５目２８科,其中古北界鸟类３８种（４８．７２％）,东洋界鸟类９种（１１．５４％）,广布型鸟类３１种（３９．７４％）,区系组成呈现南,北鸟类混杂分布,以古北界鸟类为主的特征。     

围填海对盐城珍禽自然保护区越冬水鸟群落及空间分布的影响

盐城自然保护区是全球水鸟重要的越冬地之一, 随着近几十年来围填海活动强度的不断增加, 其景观格局发生了重大变化, 这种改变势必会影响越冬水鸟的群落结构和空间分布。因此, 以盐城自然保护区北缓冲区和核心区作为研究区, 根据 1975—2013 年研究区土地利用类型变化图将其划分为围垦区和未围垦区, 分析了 2009—2013 年围垦区和未围垦区之间越冬水鸟种类、数量、多样性和空间分布的差异。结果表明: 1)围填海对水鸟的种类组成具有显著的影响, 围垦区雁鸭类水鸟的种类和数量显著高于未围垦区。土地利用类型的改变对水鸟的种类数具有显著影响, 围填海对芦苇和盐田的水鸟种类数量影响显著; 2)围填海造成土地利用类型的改变对水鸟的 Shannon-Wiener 指数具有显著的影响, 其中围垦区鱼塘的 Shannon-Wiener 指数显著高于未围垦区; 3)未围垦区碱蓬生境水鸟多度最大, 围垦区芦苇生境水鸟多度最大, 围填海造成的生境类型的改变对鹳类、鹤类、鸻鹬类、雁鸭类水鸟的栖息地选择具有较大影响。结果强调围垦后生境的可利用性和人为干扰大小决定了水鸟的群落结构和空间分布。     

河北衡水湖国家级自然保护区水鸟群落特征及其季节性变化

2020年5月—2021年4月,对河北衡水湖国家级自然保护区进行了水鸟调查,共记录水鸟82种,隶属于7目14科。其中,鹬科、鹭科和鸭科鸟类共同组成了该区域水鸟群落的优势类群,涉禽种类多、种群规模小,游禽种类少、种群规模大。豆雁、苍鹭、灰翅浮鸥等为自然保护区内水鸟群落的优势种。不同月份水鸟群落的物种丰富度、种群数量、物种多样性指数差异较大,其最大值分别出现在3—4、1和5月。总体上,衡水湖自然保护区水鸟物种丰富度维持较高水平,迁徙期水鸟物种丰富度和Shannon多样性指数更高,越冬期水鸟种群数量更大,7月水鸟物种丰富度最低、Pielou均匀度指数最高。迁徙期的水鸟群落相似度普遍较高,春季迁徙期鸻鹬类种数占比高,秋季迁徙期和越冬期雁鸭类种数占比高、种群数量大。此外,本次调查共记录国家重点保护水鸟18种,集中出现在越冬期及早春和晚秋。     

若尔盖湿地水鸟多样性季节性动态分析

若尔盖湿地位于青藏高原东缘,是我国最大的高寒泥炭湿地之一。2010年从3月至12月,对若尔盖湿地水鸟种类、数量和分布进行了较为系统的调查。共记录到48种26050只水鸟,隶属于6目12科,其中雁鸭类水鸟最多,共统计到21408只,占水鸟总数的82.2%。3月和10月是若尔盖湿地水鸟的高峰期,11月是低谷期,主要是由于水鸟的迁离和越冬水鸟尚未到达的缘故。尕海是若尔盖湿地的重要组成部分,全年物种数和水鸟数量占了整个若尔盖湿地较大的比例。卫星跟踪的结果表明,青海湖斑头雁在若尔盖湿地与云南和贵州的越冬水鸟汇合,因此加强若尔盖湿地禽流感的防控是非常重要的。     

Role for dopamine in malonate-induced damage in vivo in striatum and in vitro in mesencephalic cultures

Defects in mitochondrial energy metabolism have been implicated in the pathology of several neurodegenerative disorders. In addition, the reactive metabolites generated from the metabolism and oxidation of the neurotransmitter dopamine (DA) are thought to contribute to the damage to neurons of the basal ganglia. We have previously demonstrated that infusions of the metabolic inhibitor malonate into the striata of mice or rats produce degeneration of DA nerve terminals. In the present studies, we demonstrate that an intrastriatal infusion of malonate induces a substantial increase in DA efflux in awake, behaving mice as measured by in vivo microdialysis. Furthermore, pretreatment of mice with tetrabenazine (TBZ) or the TBZ analogue Ro 4-1284 (Ro-4), compounds that reversibly inhibit the vesicular storage of DA, attenuates the malonate-induced DA efflux as well as the damage to DA nerve terminals. Consistent with these findings, the damage to both DA and GABA neurons in mesencephalic cultures by malonate exposure was attenuated by pretreatment with TBZ or Ro-4. Treatment with these compounds did not affect the formation of free radicals or the inhibition of oxidative phosphorylation resulting from malonate exposure alone. Our data suggest that DA plays an important role in the neurotoxicity produced by malonate. These findings provide direct evidence that inhibition of succinate dehydrogenase causes an increase in extracellular DA levels and indicate that bioenergetic defects may contribute to the pathogenesis of chronic neurodegenerative diseases through a mechanism involving DA.     

Scurvy in capybaras bred in captivity in Argentine

In order to determine if the absence of vitamin C in the diet of capybaras (Hydrochoerus hydrochaeris) causes scurvy, a group of seven young individuals were fed food pellets without ascorbic acid, while another group of eight individuals received the same food with 1 g of ascorbic acid per animal per day. Animals in the first group developed signs of scurvy-like gingivitis, breaking of the incisors and death of one animal. Clinical signs appeared between 25 and 104 days from the beginning of the trial in all individuals. Growth rates of individuals deprived of vitamin C was considerably less than those observed in the control group. Deficiency of ascorbic acid had a severe effect on reproduction of another population of captive capybaras. We found that the decrease in ascorbic acid content in the diet affected pregnancy, especially during the first stages. The results obtained suggest that it is necessary to supply a suitable quantity of vitamin C in the diet of this species in captivity.     

Changes in lactate dehydrogenase activity in chicken tissues in hyperthyreosis in ontogenesis

The lactate dehydrogenase activity in reactions of lactate oxidation and synthesis was studied in subfractions of the chicken brain, heart and liver at the embryonal, early postembryonal and adult stages of development after thyroxine administration. It has been shown that during embryogenesis thyroxine predominantly enhanced the rate of lactate oxidation in the mitochondrial tissues. A marked increase in the lactate synthesis was found in cytoplasm of the adult chicken tissues. Specificity of enzyme activity alterations was detected in the chicken brain during ontogenesis after thyroxine administration.     

SSTR5 ablation in islet results in alterations in glucose homeostasis in mice

Somatostatin (SST) peptide is a potent inhibitor of insulin secretion and its effect is mediated via somatostatin receptor 5 (SSTR5) in the endocrine pancreas. To investigate the consequences of gene ablation of SSTR5 in the mouse pancreas, we have generated a mouse model in which the SSTR5 gene was specifically knocked down in the pancreatic beta cells (betaSSTR5Kd) using the Cre-lox system. Immunohistochemistry analysis showed that SSTR5 gene expression was absent in beta cells at three months of age. At the time of gene ablation, betaSSTR5Kd mice demonstrated glucose intolerance with lack of insulin response and significantly reduced serum insulin levels. Insulin tolerance test demonstrated a significant increase of insulin clearance in vivo at the same age. In vitro studies demonstrated an absence of response to SST-28 stimulation in the betaSSTR5Kd mouse islet, which was associated with a significantly reduced SST expression level in betaSSTR5Kd mice pancreata. In addition, betaSSTR5Kd mice had significantly reduced serum glucose levels and increased serum insulin levels at 12 months of age. Glucose tolerance test at an older age also indicated a persistently higher insulin level in betaSSTR5Kd mice. Further studies of betaSSTR5Kd mice had revealed elevated serum C-peptide levels at both 3 and 12 months of age, suggesting that these mice are capable of producing and releasing insulin to the periphery. These results support the hypothesis that SSTR5 plays a pivotal role in the regulation of insulin secretion in the mouse pancreas.