Dietary reconstruction of Spy I using dental microwear texture analysis

Spy I from the Meuse River Basin of Belgium is among the most recent Neandertals. This adult lived at the terminus of Marine Isotope Stage (MIS) 3 in cold steppe environments at the northern edge of the habitable zone for Neandertals where plants were relatively scarce. The dietary proclivities of Spy I are reconstructed using dental microwear texture analysis and compared to 33 Neandertals from western Eurasia, MIS 5 to MIS 3. Spy I has an elevated enamel surface complexity suggesting the consumption of course dietary items such as wild seeds, acorns, nuts, and underground storage organs laden with particles of grit. Unlike the young and old individuals from Hortus with low values for anisotropy, Spy I is closest to the adults from this site suggesting a common pattern of masticatory behavior typified this life cycle stage. Like many other Neandertals, Spy I probably consumed plant foods at appreciable levels, some of which were hard and brittle or poorly processed.     

临汾—运城盆地以水为线索的传统地域景观特征和发展启示

临汾—运城盆地是中国最早的农、盐业生产区之一,形成了具有代表性的传统地域景观。研究利用地方志、相关水利、农业等历史信息和现代考证成果,结合历史舆图和1968年卫星航拍图,以水为线索归纳其地域景观特征和营建智慧,为传承地域景观、缓解区域城镇化问题和指导未来相关规划编制提供启示。临汾—运城盆地的传统地域景观主要包括引泉、引河灌溉等引水工程主导的区域景观格局和与自然相适应的聚落防洪排涝景观体系,未来规划设计可以重点从4个方面开展：1）利用传统引水工程骨架构建区域景观格局,发挥新的城镇复合生态系统服务功能;2）开展水生态关键区域的精明保护、修复和关键资源的人文复兴;3）延续传统聚落防洪工程智慧,结合现代工程技术构建与自然相适应的城镇防洪系统;4）传承城镇水利系统、公共环境和人文空间相复合的传统,实现城镇环境品质提升。     

赣江上游流域景观生态风险的时空分异——从生产-生活-生态空间的视角

以赣江上游流域为研究对象,利用1995年、2005年、2015年的3期遥感影像,分析1995—2015年赣江上游流域的土地利用演变特征;基于景观扰动指数与景观脆弱指数构建土地利用生态风险模型;采用半变异分析、自相关分析等方法,研究了赣江上游流域土地利用风险时空变化与驱动力。结果表明:赣江上游流域城乡生活空间面积显著增加,从三生空间看,农业生产空间面积显著减少,土地利用类型由生态、生产空间向城乡生活空间转化,土地利用程度提高。1995—2015年期间土地利用生态风险逐渐上升,高-高型聚类多分布于章贡区、南康区、信丰县等附近,低-低型聚类多分布于安远县、全南县等附近,高风险区、较高面积逐渐扩大,低风险区、较低风险区面积逐渐缩小,引起土地利用类型变化的因素主要为总人口、公路里程、城镇化率等人为因素。研究结果可为区域生态安全格局构建、土地利用的优化布局提供借鉴。     

基于空间距离指数的中国西北干旱内陆河流域生态敏感性时空演变特征——以石羊河流域为例

生态敏感性是生态系统对自然环境变化和人类活动干扰的反映程度及生态环境问题发生难易程度和可能性大小的重要因素之一。以中国西北地区典型的干旱内陆河流域-石羊河流域为例,通过借鉴前人研究成果及实地调查研究,将石羊河流域生态敏感性分为生态风险敏感性、水土流失敏感性和生物多样性敏感性三个方面,并系统构建生态风险敏感性指数、水土流失敏感性指数和生物多样性敏感性指数三个定量评价指标,对石羊河流域综合生态敏感性进行研究。并通过格网编码、圈层分析,探讨近30年石羊河流域生态敏感性的时空变化。研究结果表明:(1)1987—2016年间石羊河流域生态敏感性总体上逐年降低,综合生态敏感性指数(Comprehensive ecological sensitivity index,CESI)值从1987年的1.143上升到2016年的1.287,反映出流域生态环境当前还是向着可持续发展的方向发展;(2)流域生态敏感性整体偏高,常年极度敏感区和常年重度敏感区占流域总面积的42.26%。此外,敏感性空间分异明显,流域上游及下游荒漠区敏感性相对稳定,中下游绿洲区敏感性波动变化较为频繁,且波动变化区占总面积的51.24%,这表明流域生态敏感性与人类活动及工农业生产有较为密切的关系;(3)目前流域生态敏感性整体趋于好转,但局部地区有恶化的趋势,敏感性波动降低的区域面积为11693.57km~2,占流域总面积的28.82%,敏感性波动升高的区域面积为9099.66km~2,占流域总面积的22.43%,这表明一方面在国家宏观政策的引导下,当地在生态环境保护方面做了大量工作,另一方面也表现出在全球生态环境逐渐恶化的大背景下,当地的生态环境治理工作仍然任重道远。     

拉萨河流域大型底栖动物群落结构及其与环境因子的关系

2017年8月对拉萨河流域23个采样点的底栖动物群落和环境因子特征进行了调查,采集到大型底栖动物41属(种),其中水生昆虫35属(种),占85.4%;软体动物2属(种),占4.9%;环节动物3属(种),占7.3%;线形动物1属(种),占2.4%。各点位平均物种数为8种,优势种组成差别较大,优势种主要有四节蜉属(Baetis spp.)、大蚊属(Tipula sp.)、纹石蛾属(Hydopsychesp.)、短石蛾属(Brachycentrus sp.)、水丝蚓属(Limnodrilus sp.)、摇蚊属(Chironomus sp.)等,各采样点底栖动物平均密度为362只/m2。运用生物多样性指数分析底栖动物的群落结构,Marglef丰富度指数、香农威纳指数和均匀度指数平均值分别为1.18、1.32和0.49,生物多样性指数水平较低。采用均匀度指数法和底栖动物BI指数法进行了水质评价,两种评价结果显示分别有30.3%和56.5%的采样点水质为中污染至重污染状态。典范对应分析结果表明:影响拉萨河流域底栖动物群落的主要环境因子是海拔、化学需氧量、硫化物、p H值、总磷和总氮。     

Enantioselective total synthesis,divergent optimization and preliminary biological evaluation of (indole-N-alkyl)-diketopiperazines

The first enantioselective total synthesis of the antifungal natural product (indole-N-isoprenyl)-tryptophan-valine diketopiperazine 5 was accomplished. Four stereoisomers of 5 were intentionally prepared, and the (R, R)-isomer is more favorable in enhancing the antifungal bioactivity. Divergent structural optimization of this attractive model was conducted from the chiral pool amino acids. Fine-tuning of the structure protruded the broad-spectrum antifungal 6b, which also showed good preventative efficacy against Sclerotinia scleotiorum. Compound 5d could accelerate both hypocotyl elongation and root growth of Eclipta prostrata even at the concentration of <2.5 ppm. This unique and easily accessible scaffold will be of prime importance in achieving agrochemical candidates with the novel scaffold.     

四川宣汉晚三叠世孢粉组合及其古植被与古气候意义

对四川盆地东北缘宣汉七里峡剖面须家河组进行了详细的孢粉学研究,发现丰富的孢粉化石,共计59属113种,其中包括蕨类植物孢子35属62种,裸子植物花粉22属47种,苔藓类植物孢子1属3种,以及藻类化石1属1种。据此建立一个孢粉组合,命名为Dictyophyllidites-Lunzisporites-Chasmatosporites组合(简称DLC组合),并进一步分为上、下两个亚组合。根据孢粉组合内一些重要分子的地质时代延限及与国内外有关孢粉组合的对比,提出其地质时代属于晚三叠世诺利期—瑞替期(Norian—Rhaetian)。该孢粉植物群反映了一个以蕨类植物的真蕨类、石松类和裸子植物的松柏类和苏铁类群等占主导且较为繁盛的植被面貌,揭示出温暖潮湿的亚热带—热带气候环境。     

松辽盆地来D13井地层划分对比研究

岩石组合特征和同位素数据表明,松辽盆地来D13井137.0—142.0m井段属于早白垩世晚期(Aptian—Albian期)营城组。104.2—137.0m井段光山核桃粉(Caryapollenites simplex)-拟榛莫米粉(Momipites coryloides)-朴粉未定种(Celtispollenites sp.)-具缘铁杉粉(Tsugaepollenites igniculus)组合特征可以与前人的大安组孢粉组合特征对比,反映的都是暖温带至北亚热带中生气候,而与晚白垩世嫩江组的孢粉组合特征截然不同,应该确定为早中新世晚期至中中新世的大安组。54.2—104.2m井段小蒿粉(Artemisiaepollenites minor)-拟桦粉未定种(Betulaceoipollenites sp.)-枥粉未定种(Carpinipites sp.)-水龙骨单缝孢未定种(Polypodiaceaesporites sp.)组合特征可以与前人的泰康组孢粉组合特征对比,反映的都是暖温带至北亚热带中生偏旱气候,这与前人依据岩石组合特征确定为泰康组的结论一致,孢粉组合时代分析表明,该井段沉积的时间为晚中新世至上新世初期。研究结果丰富了松辽盆地新近纪孢粉地层学内容,为松辽盆地西部斜坡区井下新近纪孢粉地层学对比提供了新资料,也为邻区新近纪生物地层学对比以及古植被和古气候分析提供了新的依据。     

Bird responses to riparian management of degraded lowland streams in southeastern Australia

We assessed the degree to which fencing, livestock exclusion, and replanting of riparian zones affected avian assemblages in massively cleared landscapes. Measurements were made at three creeks in the southern Murray–Darling Basin in southeastern Australia, each of which had circa 1‐km long treated sections and paired “untreated” circa 1‐km sections, where no fencing, planting, or stock exclusion was done. We measured the change in vegetation characteristics and abundances of native birds for up to 8 years after works were completed. Prior to data collection, we developed expected responses of bird species based on the anticipated time‐courses of change in vegetation structure. We used hierarchical Bayesian models to explore the effects of the management actions, and to account for within‐site variation in vegetation characteristics. There were major changes in vegetation structure (reductions in bare ground and increases in shrubs and tree recruitment) but avian responses generally were small and not as expected. There are at least four possible reasons for the limited avian responses: (1) there has been a long‐term decline in woodland birds across the region; (2) the study was conducted during the longest drought in the instrumental record in the study region; (3) the total amount of replanted vegetation was small in a massively denuded region; and (4) monitoring may have been over too short a term to detect responses to longer‐term changes in structural vegetation.     

Genetic diversity of Eucalyptus camaldulensis Dehnh. following population decline in response to drought and altered hydrological regime

The river red gum (Eucalyptus camaldulensis Dehnh.) inhabits riparian zones and associated floodplains throughout Australia. Following changes to hydrological regime due to river regulation and prolonged drought in south‐eastern Australia, river red gum populations within the Murray–Darling Basin have suffered substantial decline. To better understand the effect of drought on river red gum genetic diversity, we examined single nucleotide polymorphism (SNP) variation in 12 candidate genes among six red gum floodplain forest sites in Yanga National Park, which had experienced contrasting levels of drought and associated decline over an eight‐year period. We also examined genetic diversity using these markers in five additional river red gum populations from the Murray–Darling Basin to place genetic diversity results from Yanga in a regional context. Tree condition was significantly lower and mortality higher in the most drought affected sites; however, differences in overall genetic diversity and divergence were not detected among sites. No evidence of genetic adaptation in response to drought in this set of candidate genes was detected when differentiation at individual SNP loci was examined. While the overall condition of E. camaldulensis was strongly influenced by hydrological regime, our results suggest the evolutionary potential of floodplain forests in Yanga were not immediately impacted by population decline linked with drought and changes in hydrological regime. We propose that due to low genetic structure among populations in the region, genetic diversity of river red gums within the Murray–Darling Basin might be effectively conserved during periods of extended drought by protecting representative populations.