Contrasting effects of nutrients and climate on algal communities in two lakes in the Windermere catchment since the late 19th century

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铁西区城市改造过程中建筑景观的演变规律

探索城市改造过程中景观的变化规律对城市景观变化的预测有重要的指导意义。以沈阳市铁西区1997、2002、2005、2008年建筑物三维信息为基础数据。按照建筑物使用性质将其分为居住、工业、商业、教育与医疗、其他建筑5类,按照建筑物的高度将其分为平房、低层、多层、中高层、高层和超高层6类。采用转移矩阵法分析了不同时段建筑类型的更替规律。并将探索性空间数据分析法应用于建筑改造空间分布特征的研究。结果显示:1997到2002年,居住建筑是建筑改造的主体。2002年后,工业建筑成为建筑改造的主体。1997到2008年,不同高度类型的建筑更替顺序为:平房→低层建筑→多层建筑。新增建筑先以低层为主,后以中高层,逐渐以高层为主。建筑改造在空间上并不是随机分布的,而是存在显著的空间正相关关系。在局部空间范围内,建筑改造呈现成片集中改造的现象。     

黄淮平原冬小麦不同品种根系生长差异

选择黄淮平原地区当前主推品种郑麦9023,以及早期引进品种阿勃和丰产3号为材料,利用微根管技术,研究冬小麦活根长和根直径径级的分布动态,以及以活根长为基础的净生长速率的变化规律.结果表明：根直径为0.05～0.25 mm的细根是冬小麦根系的主要组成部分,根直径≤0.5 mm的细根占活根长的98%以上;冬小麦的平均根直径随着生育进程不断变化,其变化范围为0.15～0.22 mm,不同品种之间没有显著差异;活根长与根尖数呈显著正相关,表明根尖数是活根长增加的主导因素;返青期到拔节期是冬小麦根系生长最旺盛的时期,阿勃和丰产3号具有较长时期的根系增长活力,郑麦9023自拔节期以后根直径≥0.1 mm的细根根尖数占总根尖数的比例有所上升,这有利于提高生育后期根系抗性和保证根系活性稳定,以满足籽粒灌浆的需要.     

广州市萝岗区风水林植物组成及群落结构分析

通过野外实地调查,对广州市萝岗区风水林的植物组成及群落结构进行了分析.结果表明:萝岗区单个风水林面积为40 ～600 hm2,共有维管植物112科255属387种;其中,蕨类植物15科21属35种,裸子植物1科1属2种,被子植物96科233属350种;草本和乔木种类较多,分别有122和111种;灌木和藤本种类较少,分别有84和70种;其中,包含国家级珍稀保护植物5种和一些需要关注的种类,以及林下凤尾蕨(Pteris grevilleana Wall.ex Agardh)和虎克鳞盖蕨[Microlepia hookeriana (Wall.) Presl]2种广州市新记录种.优势科较明显,包含茜草科(Rubiaceae)、菊科(Compositae)、大戟科(Euphorbiaceae)、禾本科(Poaceae)、蝶形花科(Papilionaceae)、樟科( Lauraceae)等;虽然寡属科和寡种科所占比例较大,但包含种数较少;寡种属所占比例较大,占总属数的90.59％.植被类型属于南亚热带季风常绿阔叶林,以南亚热带常绿树种为主,可分为乔木层、灌木层和草本层,层间有丰富的藤本植物;作为群落的主体结构,木本植物较草本植物有优势.群落优势建群种主要为樟科、大戟科、壳斗科(Fagaceae)、山茶科(Theaceae)、胡桃科(Juglandaceae)和苏木科(Caesalpiniaceae)等科的种类,依据优势种不同可划分为13个群系.根据调查结果,对广州市萝岗区风水林的保护和资源利用提出了建议.     

The orthomolecular treatment of cancer: III. Reticulum cell sarcoma: Double complete regression induced by high-dose ascorbic acid therapy

The response of a patient with histologically proven reticulum cell sarcoma to no treatment other than large doses of ascorbic acid is described. At the time of first diagnosis, the disease was widely disseminated, and a very dramatic regression of all parameters of disease activity was induced by the continuous administration of large doses of ascorbic acid. Reduction in dosage some months later coincided with reactivation of the disease process. The reinstitution of regular high-dose ascorbic acid therapy induced a second complete remission. The case report is illustrated by serial radiographs. The significance of the therapeutic response is briefly discussed in relation to general schemes of cancer management.     

Correlations of IL-23R gene polymorphism with clinicopathological characteristics and prognosis of hepatocellular carcinoma patients after interventional therapy

In this study, we summarized the association of IL-23R gene polymorphisms with hepatocellular carcinoma (HCC). A total of 270 HCC patients were selected as HCC group, and 251 healthy individuals served as the control group. PCR-RFLP was performed to detect IL-23R gene polymorphism, including rs17375018 and rs11805303. Survival rate and risk factors of HCC were identified. The findings suggested that IL-23R rs17375018 was correlated with genetic susceptibility to HCC, and GC haplotype was closely linked with the risk factors of HCC. Moreover, rs17375018 polymorphism was related to portal vein tumor thrombus (PVTT) and alcohol consumption in HCC patients, while prognosis was better in HCC patients with AA genotype of rs17375018 polymorphism. Lastly, GG genotype in rs17375018, PVTT and TNM stage III and IV were identified as independent risk factors for HCC. In conclusion, IL-23R rs17375018 polymorphism might serve as a prognostic factor in patients with HCC after interventional therapy.     

陇中黄土丘陵区土地利用强度-生态系统服务-人类福祉时空关系研究——以安定区为例

基于土地利用和社会统计数据,构建了"土地利用强度-生态系统服务-人类福祉"多尺度分析框架,从县区和乡镇尺度探讨了定西市安定区1990—2015年土地利用强度-生态系统服务-人类福祉的时空权衡/协同关系。结果表明:1990—2015年安定区土地利用强度-生态系统服务-人类福祉关系变化存在区域整体相似性和乡镇局部差异性;土地利用强度的增加,提高了供给服务和生产资料供给福祉,但弱化了调节和支持服务;供给与支持服务权衡主要集中于安定区北部和西南部。该区生态系统服务间的权衡程度较高,不利于生态系统服务保育和居民福祉的持续提升。区域的脱贫致富因立足于提高居民福祉,退耕还林还草、发展特色高效产业、劳务输出等是实现该区社会生态系统的经济收益与生态效益共赢的有效途径。     

城市周边农田景观中非农生境与土壤动物的协同关系——以沈阳市沈北新区为例

农田景观中非农生境对生物多样性保护、耕地多功能性和农业产量等具有重要影响.本文选择中国城市化过程中生物多样性保护与农业高产需求相互冲突的典型地区沈阳市沈北新区为研究区,采用信息熵模型划分为城市近郊、城市边缘区和乡村区域,采用手捡法和Baermann 法调查,鉴定了节肢动物和土壤线虫,并通过线性回归分析确定了非农生境类型、结构及数量与土壤动物的协同关系.结果表明： 沈北新区农田景观的非农生境斑块面积均小于1 hm².随着与城市中心距离的增加,非农生境类型和比例逐渐增加,面积比例呈倒“U”型变化,斑块数量比例从8.6%增加到27.8%;土壤动物个体数呈现“U”型变化,物种量无明显变化规律.乡村和城市近郊的非农生境斑块数量比与土壤动物个体数呈正向协同关系,城市边缘区无明显规律;非农生境面积比与土壤动物个体数均呈反向协同关系;非农生境斑块数量比和面积比与土壤动物物种量均无明显协同关系.     

珠海万山海域生态系统服务价值与能值评估

采用生态系统服务货币价值和能值价值分析方法,对珠海万山区2007-2012年海洋生态系统服务价值变化进行分析.结果表明:研究期间,珠海万山区海洋生态系统服务货币价值和能值价值分别由772163万元和1.04× 1022 sej上升至1151284万元和1.97×1022 sej.货币价值和能值价值都能对海洋生态系统服务价值的变动趋势进行预测,但两者所反映的价值结构有所不同,生态能值更能客观地评价生态系统服务价值.生态文明建设对于合理开发海洋资源,优化海洋生态系统服务功能有着重要意义,是推动海洋生态系统服务结构发展的内在驱动力.     

Constructed Wetland Habitat for American Avocet and Black-Necked Stilt Foraging and Nesting

Abstract In 1994, a 117-ha wetland was designed, constructed, and operated by the Tulare Lake Drainage District (TLDD), California, USA, to provide foraging and nesting habitat for American avocets (Recurvirostra americana) and black-necked stilts (Himantopus mexicanus). The wetland was operated seasonally in compliance with regulatory requirements to compensate for impacts to stilts, avocets, and other wildlife exposed to elevated selenium concentrations, fluctuating water levels resulting in nest flooding, and high nest-predation rates at the TLDD agricultural drainage evaporation basins. Water supply for the wetland was from low-selenium (typically <2 μg/L) saline agricultural drainage water, although the facility also had capability to blend and use freshwater and saline supplies. Coincident with wetland construction, 2 evaporation basins totaling 1,174 ha were physically modified and operated to discourage their use by shorebirds. In the first year of wetland operation (1995), American avocet and black-necked stilt nest construction at the wetland was 17.6 nests/ha. This compares to a preproject (1994) combined density of 1.9 nests/ha at the evaporation basins. From 1995 through 2004, annual nesting attempts by American avocets and black-necked stilts at the wetland averaged 2,896 per year (24.8 nests/ha). American avocets and black-necked stilts represented 91% of the nests observed at the wetland. Over the 10-year monitoring period, nest success at the wetland averaged 82% for American avocets and 75% for black-necked stilts. We estimated nest predation rates at the constructed wetland to be <1%. During the same period, American avocet and black-necked stilt nesting at the evaporation basins declined from 2,266 in 1994 to 9 in 2004. The constructed wetland has proven to be effective in attracting and providing suitable nesting habitat for large numbers of avocets and stilts. Results of this long-term study confirm the validity of management recommendations for American avocets and black-necked stilts and suggest that agricultural drainage can be successfully managed to provide highly productive managed wetlands.