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Patterns of sperm use by twice-mated female Queensland fruit flies

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Insect Science 2022年第4期29卷 1159-1169页

作者： Jason Shadmany Siu F.Lee Thu N.M.Nguyen Phillip W.Taylor Applied BioSciences Macquarie UniversityNorth RydeNSWAustralia csiro land and water Black MountainACTAustralia School of BioSciences University of MelbourneParkvilleVictoriaAustralia

Multiple mating by females,polyandry,is common in insects,including in tephritid fruit flies.Female insects that remate commonly store sperm of multiple males.How the sperm of different males contribute to paternity is an important element of sexual selection.Sexual behavior and reproduction of the Queensland fruit fly(Qfly),Bactrocera tryoni,has been extensively investigated both in relation to understanding this economically important species’reproductive biology and in relation to implications for Sterile Insect Technique(SIT),whereby sterile flies are released to constrain reproduction of pest populations.Despite numerous studies of pre-and postcopulatory sexual selection in Qfly,there have been no direct studies of paternity patterns in polyandrous female Qflies.We used two morphologically distinguishable lines to investigate patterns of sperm use in Qfly.The two lines showed comparable mating performance evidenced by similar mating and remating frequency,copula duration,and proportion of second mate paternity(P2)between reciprocal crosses.The mechanism of sperm usage,with P2 close to 0.5 immediately after the second mating followed by gradual decrease of P2 as females aged,is most consistent with stratification or repositioning of sperm.Patterns observed in the present study are compared with the available information from other tephritid fruit flies,and are discussed in relation to this species’reproductive biology,known patterns of sperm storage,and SIT.

关键词： muliple mating polyandry sperm competition sperm pecedence Tephritidac

Quantification of hookworm ova from wastewater matrices using quantitative PCR

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Journal of Environmental Sciences 2017年第7期29卷 231-237页

作者： Pradip Gyawali Warish Ahmed Jatinder P.Sidhu Paul Jagals Simon Toze csiro land and water Ecosciences Precinct School of Public Health The University of Queensland

A quantitative PCR（q PCR） assay was used to quantify Ancylostoma caninum ova in wastewater and sludge samples.We estimated the average gene copy numbers for a single ovum using a mixed population of ova.The average gene copy numbers derived from the mixed population were used to estimate numbers of hookworm ova in A.caninum seeded and unseeded wastewater and sludge samples.The newly developed qP CR assay estimated an average of3.7 × 10~3 gene copies per ovum,which was then validated by seeding known numbers of hookworm ova into treated wastewater.The qP CR estimated an average of（1.1 ± 0.1）,（8.6 ± 2.9）and（67.3 ± 10.4） ova for treated wastewater that was seeded with（1 ± 0）,（10 ± 2） and（100 ± 21）ova,respectively.The further application of the q PCR assay for the quantification of A.caninum ova was determined by seeding a known numbers of ova into the wastewater matrices.The qP CR results indicated that 50%,90% and 67% of treated wastewater（1 L）,raw wastewater（1 L）and sludge（~4 g） samples had variable numbers of A.caninum gene copies.After conversion of the q PCR estimated gene copy numbers to ova for treated wastewater,raw wastewater,and sludge samples,had an average of 0.02,1.24 and 67 ova,respectively.The result of this study indicated that qP CR can be used for the quantification of hookworm ova from wastewater and sludge samples;however,caution is advised in interpreting qP CR generated data for health risk assessment.

关键词： Wastewater matrices Quantitative PCR Hookworm ova Health risks

Mapping groundwater dependent ecosystem potential in a semi-arid environment using aremote sensing-based multiple-lines-of-evidence approach

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International Journal of Digital Earth 2023年第1期16卷 375-406页

作者： Stephen G.Fildes Tanya M.Doody David Bruce Ian F.Clark Okke Batelaan UniSA STEM University of South AustraliaAdelaideAustralia csiro Land and WaterAdelaideAustralia National Centre for Groundwater Research and Training(NCGRT) College of Science and EngineeringFlinders UniversityBedford ParkAustralia

Groundwater dependent ecosystems(GDEs)are vulnerable to groundwater regime changes.However,their protection is often hampered by challenges in their identification.Within is presented a remote sensing-based GDE potential mapping approach based on the persistency of relevant vegetation parameters during prolonged dry periods as an indicator of potential‘consistency’of water supply(e.***.groundwater).The study uses a novel approach to characterising persistency for selected vegetation parameters based on a normalised difference measure and an adaptation of the coefficient of variation statistic.Aggregation of parameters was facilitated through the analytic hierarchy process providing a structured weighting approach to minimise parameter bias.The approach is demonstrated in the semi-arid Flinders Ranges of South Australia where new groundwater resources are being sought to support local domestic and industry needs.Variations in GDE potential were mapped to better target areas where exploration of groundwater should be avoided.Mapping results indicated a high-level of agreement of 77%with an independent springs dataset,along with an 87%agreement with areas coinciding with known phreatophyte species and depths to groundwater.The index-based mapping approach has potential applicability across landscapes,as it normalises for variations in vegetation cover,minimises technical overheads,and employs continental-wide remote sensing data-products.

关键词： coefficient of variation NDVI coefficient of variation fractional cover barest Earth wetness percentiles actual evapotranspiration analytic hierarchy process groundwater potential

Using Bayesian multitemporal classification to monitor tropical forest cover changes in Kalimantan,Indonesia

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International Journal of Digital Earth 2022年第1期15卷 2061-2077页

作者： Inggit Lolita Sari Christopher J.Weston Glenn J.Newnham Liubov Volkova Faculty of Science School of Ecosystem and Forest SciencesThe University of MelbourneCreswickAustralia Research Center for Remote Sensing National Research and Innovation Agency (BRIN)JakartaIndonesia csiro land and water Clayton SouthAustralia

Significant areas of native forest in Kalimantan,on the island of Borneo,have been cleared for the expansion of plantations of oil palm and rubber.In this study multisource remote sensing was used to develop a time series of land cover maps that distinguish native forest from plantations.Using a study area in east Kalimantan,landsat images were combined with either ALOS PALSAR or Sentinel-1 images to map four land cover classes(native forest,oil palm plantation,rubber plantation,non-forest).Bayesian multitemporal classification was applied to increase map accuracy and maps were validated using a confusion matrix;final map overall accuracy was>90%.Over 18 years from 2000 to 2018 nearly half the native forests in the study area were converted to either non-forest or plantations of either rubber or oil palm,with the highest losses between 2015 and 2016.Trending upwards from 2008 large areas of degraded or cleared forests,mapped as non-forest,were converted to oil palm plantation.Conversion of native forests to plantation mainly occurred in lowland and wetland forest,while significant forest regrowth was detected in degraded peatland.These maps will help Indonesia with strategies and policies for balancing economic growth and conservation.

关键词： Multitemporal classification Bayesian networks landsat ALOS PALSAR sentinel-1 Indonesia

Competitive effect, but not competitive response, varies along a climatic gradient depending on tree species identity

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Forest Ecosystems 2024年第2期11卷 142-151页

作者： Teresa Valor Lluís Coll David I.Forrester Hans Pretzsch Miren del Río Kamil Bielak Bogdan Brzeziecki Franz Binder Torben Hilmers Zuzana Sitková Roberto Tognetti Aitor Ameztegui Department of Agricultural and Forest Sciences and Engineering(DCEFA) University of LleidaAv.Alcalde Rovira Roure 191E25198 LleidaSpain Joint Research Unit CTFC-AGROTECNIO-CERCA Ctra.Sant LlorençKm.225280SolsonaSpain Swiss Federal Institute of Forest Snow and Landscape Research WSLZürcherstrasse 1118903BirmensdorfSwitzerland csiro land and water GPO Box 1700CanberraACT2601Australia Chair of Forest Growth and Yield Science School of Life Sciences WeihenstephanTechnical University of MunichHans-Carl-Von-Carlowitz-Platz 285354FreisingGermany Forest Research Center INIA-CSICCtra.A Coruña Km 7.528040MadridSpain IuFOR Sustainable Forest Management Research InstituteUniversity of Valladolid&INIASpain Department of Silviculture Institute of Forest SciencesWarsaw University of Life SciencesNowoursynowska 159/3402776WarsawPoland Bavarian State Institute of Forestry(LWF) Hans-Carl-von-Carlowitz-Platz 1D-85354FreisingGermany National Forest Centre Forest Research InstituteT.G.Masaryka 2296001ZvolenSlovakia Faculty of Agricultural Environmental and Food SciencesFree University of Bozen-Bolzano Piazza Università1 I-39100Bolzano

Background: Understanding the role of species identity in interactions among individuals is crucial for assessing the productivity and stability of mixed forests over time. However, there is limited knowledge concerning the variation in competitive effect and response of different species along climatic gradients. In this study, we investigated the importance of climate, tree size, and competition on the growth of three tree species: spruce(Picea abies), fir(Abies alba), and beech(Fagus sylvatica), and examined their competitive response and effect along a climatic gradient.Methods: We selected 39 plots distributed across the European mountains with records of the position and growth of 5,759 individuals. For each target species, models relating tree growth to tree size, climate and competition were proposed. Competition was modelled using a neighbourhood competition index that considered the effects of inter-and intraspecific competition on target trees. Competitive responses and effects were related to climate.Likelihood methods and information theory were used to select the best model.Results: Our findings revealed that competition had a greater impact on target species growth than tree size or climate. Climate did influence the competitive effects of neighbouring species, but it did not affect the target species? response to competition. The strength of competitive effects varied along the gradient, contingent on the identity of the interacting species. When the target species exhibited an intermediate competitive effect relative to neighbouring species, both higher inter-than intraspecific competitive effects and competition reduction occurred along the gradient. Notably, species competitive effects were most pronounced when the target species' growth was at its peak and weakest when growing conditions were far from their maximum.Conclusions: Climate modulates the effects of competition from neighbouring trees on the target tree and not the susceptibility of the target tree to competition. The modelling appr

关键词： Competition coefficient Competition reduction Interspecific competition Intraspecific competition Mixing effects Mixed species forest Neighbourhood models Plant-plant interactions

Numerical Approach for Thermal History Modelling in Multi-Episodic Rifting Basins

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Journal of Earth Science 2014年第3期25卷 519-528页

作者： Bo Kang Xinong Xie Tao Cui Key Laboratory of Tectonics and Petroleum Resources of Ministry of Education China University of Geosciences csiro land and water

Pre-existing models for thermal history modelling have shown deficiency in explicit algorithms to establish the quantitative relationship between maturity indices and thermal gradients in some sedimentary basins that experienced multi-episodic rifting evolution. In this study, a forward and inverse combination model（FICM） is proposed to estimate the vitrinite reflectance（Ro） and thermal gradients. The forward module is used to calculate Ro values. It couples the EASY%Ro model with burial history reconstruction with consideration of thermal gradient variations during basin evolution. The inverse module reconstructs histoical thermal gradients by calibrating cmputed Ro against measured Ro data. The time-temperature series is a necessary input for both forward and inverse modules. Sample density is a profound factor influencing the accuracy of modelling results. In order to obtain satisfying outputs, a sufficient sample density is required. Thermal gradients are assumed to vary linearly between two given samples. Modelling results of case studies indicate that the sensitivity of heating time to Ro evlution is differnt with thermal gradients depending on geolgoical setting. Three difffernt districts, which include the time-sensitive area, the temperature-sensitive area and the non-sensitive area, can be recognized on the the relationship map among Ro variations, heating time and geothermal gradients. This model can be applied to reconstruct the thermal history and maturation evolution in a basin that has undergone complex multi-episodic rifting.

关键词： thermal history maturity EASY%Ro burial history vitrinite reflectance.

Supply-Demand Analysis of Urban Emergency Shelters Based on Spatiotemporal Population Estimation

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International Journal of Disaster Risk Science 2020年第4期11卷 519-537页

作者： Xiaodong Zhang Jia Yu Yun Chen Jiahong Wen Jiayan Chen Zhan'e Yin School of Environmental and Geographical Sciences Shanghai Normal UniversityShanghai 200234China csiro land and water Canberra 2601Australia

Supply–demand analysis is an important part of the planning of urban emergency shelters.Using Pudong New Area,Shanghai,China as an example,this study estimated daytime and nighttime population of the study area based on fine-scale land use data,census data,statistical yearbook information,and Tencent user-density big data.An exponential function-based,probability density estimation method was used to analyze the spatial supply of and demand for shelters under an earthquake scenario.The results show that even if all potential available shelters are considered,they still cannot satisfy the demand of the existing population for evacuation and sheltering,especially in the northern region of Pudong,under both the daytime and the nighttime scenarios.The proposed method can reveal the spatiotemporal imbalance between shelter supply and demand.We also conducted a preliminary location selection analysis of shelters based on the supply–demand analysis results.The location selection results demonstrate the advantage of the proposed method.It can be applied to identify the areas where the supply of shelters is seriously inadequate,and provide effective decision support for the planning of urban emergency shelters.

关键词： Big data China population estimation Probability density estimation Supply-demand analysis Urban emergency shelters

Streamflow response to climate variability and human activities in the upper catchment of the Yellow River Basin

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Science China(Technological Sciences) 2009年第11期52卷 3249-3256页

作者： ZHAO FangFang XU ZongXue ZHANG Lu ZUO DePeng Key Laboratory of water and Sediment Sciences Ministry of EducationCollege of Water SciencesBeijing Normal UniversityBeijing 100875China csiro land and water Canberra ACT 2601Australia

Both sensitivity-based method and simulation method are used to analyze the streamflow response to climate variability and human activities in the upper catchment of the Yellow River Basin (UYRB) in this study. The separation regime of effects from climate variability and human activities is investigated. Results show that the changes of streamflow are more sensitive to precipitation than potential evapotranspiration (PET). Effect of climate variability on streamflow estimated using the sensitivity-based method is weak in the upper catchment of Jimai station, and strong in the upper catchment of Lanzhou station, where the climate effects accounted for about 50% of total streamflow changes. Effects of human activities on streamflow accounted for about 40% in the UYRB, with weaker effects in the upper catchment of Tangnaihai station than those in the upper catchment of Lanzhou station. Both climate variability and human activities are main factors to affect the changes of streamflow in the UYRB.

关键词： climate variability human activities Yellow River streamflow response

Validity of the Bouchet's complementary relationship at 102 observatories across China

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Science China Earth Sciences 2009年第5期52卷 708-713页

作者： YU JingJie1,2,ZHANG YongQiang3,LIU ChangMing1,2 1 Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences,Beijing 100101,China 2 Key Laboratory of water Cycle and Related land Surface Processes,Chinese Academy of Sciences,Beijing 100101,China 3 csiro land and water,PO Box 1666,Canberra ACT 2601,Australia Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Key Laboratory of water Cycle and Related land Surface Processes Chinese Academy of Sciences Beijing China csiro land and water Canberra Australia

Bouchet in 1963 hypothesized that for large homogeneous land surface with minimum advection of heat and moisture,there exists a 1:1 complementary relationship of potential and actual evaporation coupled through land-atmosphere feedbacks.The complementary relationship has been widely used to estimate regional actual evaporation and explain the pan evaporation paradox.We examine the standardized potential evaporation(potential evaporation divided by wet environment evaporation) at 102 observatories at different elevations across China.Generally,the relationship is appropriate at the low elevations(<1000 m).With the increase of elevation,vapor transfer power becomes much less than radiation energy budget because of lower vapor pressure deficit and stronger global solar radiation.As a result,at the high elevations(over 1000 m),the excess energy resulted by limited moisture availability is not enough to be converted into drying power of the air.This result suggests that the complementary relationship is asymmetric at the high elevations.

关键词： evaporation complementary relationship elevation China