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Soil aggregation and aggregate-associated organic carbon under typical natural halophyte communities in arid saline areas of Northwest China

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Pedosphere 2020年第2期30卷 236-243页

作者： Zhibo CHENG jingya WANG William jgale Haichang YANG Fenghua ZHANG College of Agronomy Shihezi UniversityXinjiang 832003China Key Laboratory of Oasis Ecology Agriculture of Xinjiang Shihezi UniversityXinjiang 832003China

Information on the effects of halophyte communities on soil organic carbon(SOC)is useful for sequestrating C in arid *** this study,we identified four typical natural halophyte communities in the Manasi River Basin in Xinjiang Province,Northeast China,namely,Karelinia caspia(Pall.)Less.,Bassia dasyphylla(*** ***.)Kuntze,Haloxylon ammodendron(***.)Bunge,and Tamarix ramosissima *** compared soil aggregation and aggregated-associated SOC under these *** aggregate fraction of 0.053–0.25 mm accounted for 47%–75%of the total soil mass,significantly more than the>0.25 and0.25 mm aggregates(13.3%–43.8%)and *** community having more0.25 mm fraction,followed by the***(4.9 g kg^-1)>***(4.2 g kg^-1)>***(3.4 g kg^-1).The *** community had the highest total SOC and aggregate-associated SOC,which was primarily because aggregate-associated SOC content at the 0–10 and 10–20 cm depths under this community were higher than those under other plant *** *** community could be beneficial for increasing SOC in saline soils in the arid region.

关键词： arid regions C sequestration soil aggregates soil organic C saline soils

Control of the carrier-envelope phases of a synchronously pumped femtosecond optical parametric oscillator and its applications

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Chinese Science Bulletin 2008年第5期53卷 642-651页

作者： SUN jingHua Barry j S gale Derryck T Reid Ultrafast Optics Group School of Engineering and Physical Sciences Heriot-Watt University Edinburgh EH14 4AS UK Laboratory of Optical Physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China

The intrinsic synchronization, multi-color outputs and related carrier-envelope phases (CEP) among pulses bring advantages to synchronously pumped femtosecond optical parametric oscillators and the pumping sources for broadband frequency comb generation and ultrashort waveform coherent syn-thesis. In this paper, we discuss our latest research results in this field, which cover the following as-pects: the phase relationship and energy conservation law in an OPO and related experimental verifi-cation; control of the pumping Ti:sapphire femtosecond laser's CEP by self-referencing technology, and its repetition-rate locking by piezoelectric transducer (PZT); CEP locking of the pulses from the OPO by beating the non-phase-matched visible outputs against pump supercontinuum to obtain a driving signal for a fast PZT on the OPO end mirror; the generation of a broadband frequency comb spanning from 400 nm to 2.4 μm with 1.2 kHz bandwidth; and the realization of coherent interference between phase controlled pump pulses and signal second harmonic pulses.

关键词：光学参数振荡器载波包络相同步控制超短光脉冲

Plant-frugivore interactions in an intact tropical forest in north-east Thailand

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Integrative Zoology 2011年第3期6卷 195-212页

作者： Wangworn SANKAMETHAWEE Andrew j.PIERCE George A.gale Britta Denise HARDESTY Conservation Ecology Program School of Bioresources and TechnologyKing Mongkut’s University of Technology ThonburiBangkok Thailand Walai Rukhavej Botanical Research Institute Mahasarakham UniversityMahasarakhamThailand CSIRO Ecosystem Sciences AthertonQueenslandAustralia

Fleshy-fruited plants in tropical forests largely rely on vertebrate frugivores to disperse their *** this plant-animal interaction is typically considered a diffuse mutualism,it is fundamental as it provides the template on which tropical forest communities are *** applied a mutualistic network approach to investigate the relationship between small-fruited fleshy plant species and the fruit-eating bird community in an intact evergreen forest in north-east Thailand.A minimum of 53 bird species consumed fruits of 136 plant ***-avian frugivore networks were highly asymmetrical,with observed networks filling 30%of all potential *** some of the missing links in the present study might be due to undersampling,forbidden links can be attributed to size constraints,accessibility and phenological uncoupling,and although the majority of missing links were unknown(58.2%),many were probably due to a given bird species being either rare or only a very occasional fruit *** most common frugivores were bulbuls,barbets and fairy-bluebirds,which were responsible for the majority of fruit removal from small fleshy fruited species in our *** birds seemed to be a minor component of the plant-frugivore networks,accounting for only 3%of feeding visits to fruiting trees;they filled 2%of the overall potential *** majority of interactions were generalized unspecific;however,Saurauia roxburghii *** to be dependent on flowerpeckers for dispersal,while Thick-billed Pigeons were only seen to eat figs.

关键词： avian frugivore nestedness plant-frugivore networks seed dispersal tropical forest

The Global Boundary Stratotype Section and Point （GSSP） for the base of the Cenomanian Stage, Mont Risou, Hautes-Alpes, France

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Episodes 2004年第1期27卷 21-32页

作者： W.j.Kennedy A.S.gale j.A.Lees M.Caron OxfordUniversityMuseumofNaturalHistory ParksRoadOxfordOXI3PWU.K. DepartmentofPalaeontology TheNaturalHistoryMuseumCromwellRoadLondonSW75BPU.K.andSchoolofEarthandEnvironmentalSciencesUniversityofGreenwichChathamMaritimeCampusChathamKentME44AWU.K. ResearchSchoolofGeologicalandGeophysicalSciences BirkbeckCollegeandUniversityCollegeLondonGowerStreetLondonWCIE6BTU.K. InstitutdeGeologie UniversitedeFribourgCH-1700FribourgSwitzerland.

Following the unanimous recommendation of the International Commission on Stratigraphy, the Global boundary Stratotype Section and Point (GSSP) for the base of the Cenomanian Stage is defined at a level 36 metres below the top of the Marnes Bleues Formation, a level that corresponds to the the first appearance of the planktonic foraminiferan Rotalipora globotruncanoides Sigal, 1948, on the south side of Mont Risou, east of Rosans, Haute-Alpes, France, where it can be placed in the context of a series of secondary marker levels based on nannofossils, planktonic foraminifera, ammonites,and an ornate δ^13C curve.

关键词：地层学地层分界线层型地质构造

Process and Mechanism for the Development of Physical Crusts in Three Typical Chinese Soils

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Pedosphere 2013年第3期23卷 321-332页

作者： BU Chong-Feng W.j.gale CAI Qiang-Guo WU Shu-Fang Institute of Soil and Water Conservation Northwest A&F University Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resources College of Resources and Environment Northwest A&F University Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences College of Water Resources and Architectural Engineering Northwest A&F University

To compare the development of physical crusts in three typical cultivated soils of China, a black soil （Luvic Phaeozem）, a loess soil （Haplic Luvisol）, and a purple soil （Calcaric Regosol） were packed in splash plates with covered and uncovered treatments, and exposed to simulated rainfall. Meshes covered above the surfaces of half of soil samples to simulate the effects of crop residue on crusting. The results indicated a progressive breakdown of aggregates on the soil surface as rainfall continued. The bulk density and shear strength on the surface of the three soil types increased logarithmically as rainfall duration increased. During the first 30 min of simulated rainfall, the purple soil developed a 7-8 mm thick crust and the loess soil developed a 3-4 mm thick crust. The black soil developed a distinguishable, but still unstable, crust after 80 rain of simulated rainfall. Soil organic matter （SOM） content, the mean weight diameter （MWD） of soil aggregates, and soil clay content were negatively correlated with the rate of crust formation, whereas the percentage of aggregate dispersion （PAD）, the exchangeable sodium percentage （ESP）, and the silt and sand contents were positively correlated with crusting. Mechanical breakdown caused by raindrop impact was the primary mechanism of crust formation in the black soil with more stable aggregates （MWD 25.0 mm, PAD 3.1%） and higher SOM content （42.6 g kg-1）. Slaking and mechanical eluviation were the primary mechanisms of crust formation in the purple soil with low clay content （103 g kg-1）, cation exchange capacity （CEC, 228 mmol kg-1）, ESP （0.60%）, and SOM （17.2 g kg-1）. Mechanical breakdown and slaking were the most important in the loess soil with low CEC （80.6 mmol kg-1）, ESP （1.29%）, SOM （9.82 g kg-1）, and high PAD （71.7%） and MWD （4.6 mm）. Simulated residue cover reduced crust formation in black and loess soils, but increased crust formation in purple soil.

关键词： aggregate bulk density shear strength simulated rainfall soil properties

Roost selection of the endangered Spotted Greenshank(Tringa guttifer) in critical habitat in the Inner Gulf of Thailand

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Avian Research 2019年第2期10卷 199-208页

作者： Chenxing Yu Dusit Ngoprasert Philip D.Round Andrew j.Pierce Tommaso Savini George A.gale Conservation Ecology Program School of Bioresources and TechnologyKing Mongkut’s University of Technology ThonburiBangkok 10150Thailand. Department of Biology Mahidol UniversityRama 6 RoadBangkok 10400Thailand

Background: Roost-site quality can significantly affect the individual fitness of shorebirds, but roost sites remain poorly described for many threatened species on the East Asian–Australasian Flyway. We studied roost-site selection of the globally endangered Spotted Greenshank (Tringa guttifer) in the Inner Gulf of Thailand, an area which supports approximately 24% of their global wintering population, during two non-breeding seasons (October 2014–May 2015 and December 2015–February 2016). Methods: We measured nine variables associated with roost site characteristics including water depth, indicators of disturbance/predation risk, and associations with other shorebird species. We predicted that roost ponds with shallow water in proximity to foraging sites would receive higher usage than those further away. Results: A total of 94 sites were measured of which 46 were used for roosts with 23 used repeatedly. All used sites were human-modified ponds, of which 44 were used for salt farming and two used for aquaculture. Roosts were on average 1.10 ± 0.78 (SE) km from foraging sites and 5.8 ± 2.4 cm deep. The most supported model indicated that roost sites were negatively associated with distance to foraging sites and positively associated with the presence of Grey Plover (Pluvialis squatarola) and water depth. Conclusions: Traditional saltpans and other artificial wetlands near (< 1 km) mudflats serve as the primary high-tide roost habitat in the Inner Gulf of Thailand for this Spotted Greenshank population and perhaps seven other globally threatened or near-threatened species. Critically, all observed roost sites are on private land with no formal protection and thus will require creative public–private partnerships to manage sustainably.

关键词： Habitat selection Saltpans Shorebirds

Road induced edge effects on a forest bird community in tropical Asia

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Avian Research 2018年第2期9卷 123-135页

作者： Daphawan Khamcha Richard T.Corlett Larkin A.Powell Tommaso Savini Antony j.Lynam George A.gale Conservation Ecology Program School of Bioresources and Technology King Mongkut’s University of Technology Thonburi Center for Integrative Conservation Xishuangbanna Tropical Botanical Garden Chinese Academy of Sciences School of Natural Resources University of Nebraska-Lincoln Wildlife Conservation Society Global Conservation Program

Background: Edge effects cause changes in bird community richness, abundance, and/or distribution within a landscape, but the avian guilds most influenced can vary among regions. Although Southeast Asia has the highest rates of deforestation and projected species loss, and is currently undergoing an explosive growth in road infrastructure, there have been few studies of the effects of forest edges on avian communities in this ***: We examined avian community structure in a dry evergreen forest in northeastern Thailand adjacent to a five-lane highway. We evaluated the richness and abundance of birds in 11 guilds at 24 survey points on three parallel transects perpendicular to the edge. At each point, 10-min surveys were conducted during February-August 2014 and March-August 2015. Vegetation measurements were conducted at 16 of the bird survey points and ambient noise was measured at all 24 survey ***: We found a strongly negative response to the forest edge for bark-gleaning, sallying, terrestrial, and understory insectivores and a weakly negative response for arboreal frugivore-insectivores, foliage gleaning insectivores, and raptors. Densities of trees and the percentage canopy cover were higher in the interior, and the ambient noise was lower. In contrast, arboreal nectarivore-insectivores responded positively to the forest edge, where there was a higher vegetation cover in the ground layer, a lower tree density, and a higher level of ambient ***: Planners should avoid road development in forests of high conservation value to reduce impacts on biodiversity. Where avoidance is impossible, a number of potential mitigation methods are available, but more detailed assessments of these are needed before they are applied in this region.

关键词： Road edge Avian guilds Dry evergreen forest Thailand

Tolerance to Zn deficiency and P-Zn interaction in wheat seedlings cultured in chelator-buffered solutions

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journal of Arid Land 2011年第3期3卷 206-213页

作者： WenXuan MAI XiaoHong TIAN Willam jeffery gale XiWen YANG XinChun LU College of Resources and Environment Northwest A＆F University Yangling 712100 China Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

Zinc deficiency is a common constraint for wheat production in the regions with limited precipitation,particularly in the regions with high levels of available phosphate （P） in *** experiments were conducted using chelator-buffered nutrient solutions to characterize differences in tolerance to Zn deficiency among three winter wheat （Triticum aestivum L）.genotypes and to investigate the relationship between P and Zn nutrition in wheat *** indices,Zn efficiency,relative shoot-to-root ratio,total Zn uptake in shoot,and shoot dry weight were used to compare the tolerance to Zn deficiency among three wheat *** results indicated that the four indices could be used in breeding selection for Zn uptake-efficient *** genotype H6712 was the most tolerant to Zn deficient,followed by M19,and then ***,H6712 had the highest Zn uptake efficiency among the three *** addition of P to the growth medium increased Zn uptake and translocation from roots to *** Zn content of the wheat plant was 43% higher with 0.6 mmol/L P treatment than that of control with 0 mmol /L P *** Zn translocation ratios from roots to shoots were increased by 16% and 26% with 0.6 mmol/L P treatment and 3 mmol/L P treatment,respectively,compared with 0 mmol/L P *** contrast,high Zn concentrations in the growth medium inhibited P translocation from roots to shoots,but the inhibitive effects were not ***-six percent of P taken up by wheat plants was translocated to the wheat shoots at 0 μmol/L Zn treatment,while the percent was 60% at 3 μmol/L Zn *** result may be due to the fact that the wheat plants need more P than Zn.

关键词： chelator-buffered solution tolerance to Zn deficiency P and Zn interaction

Development of the sexually dimorphic nucleus of the preoptic area and the influence of estrogen-like compounds

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Neural Regeneration Research 2013年第29期8卷 2763-2774页

作者： Zhen He Sherry Ann Ferguson Li Cui Lazar john Greenfield Merle gale Paule Division of Neurotoxicology National Center for Toxicological ResearchFood and Drug Administration Department of Neurology University of Arkansas for Medical Sciences

One of the well-defined sexually dimorphic structures in the brain is the sexually dimorphic nucleus, a cluster of cells located in the preoptic area of the hypothalamus. The rodent sexually dimorphic nucleus of the preoptic area can be delineated histologically using conventional Nissl staining or immunohistochemically using calbindin D28K immunoreactivity. There is increasing use of the cal- bindin D28K-delineated neural cluster to define the sexually dimorphic nucleus of the preoptic area in rodents. Several mechanisms are proposed to underlie the processes that contribute to the sexual dimorphism （size difference） of the sexually dimorphic nucleus of the preoptic area. Recent evidence indicates that stem cell activity, including proliferation and migration presumably from the 3^rd ventricle stem cell niche, may play a critical role in the postnatal development of the sexually dimorphic nucleus of the preoptic area and its distinguishing sexually dimorphic feature： a signifi-cantly larger volume in males. Sex hormones and estrogen-like compounds can affect the size of the sexually dimorphic nucleus of the preoptic area. Despite considerable research, it remains un-clear whether estrogen-like compounds and/or sex hormones increase size of the sexually dimor-phic nucleus of the preoptic area via an increase in stem cell activity originating from the 3^rd ventricle stern cell niche.

关键词： neural regeneration review sexual orientation sexual behavior calbindin D28K estrogen-likecompound bisphenol A neural stem cells grants-supported paper neuroregeneration