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Zhu H.,CAS Changchun Northeast Institute of Geography and Agroecology | Banuelos G.,U.S. Department of Agriculture
Journal of Hazardous Materials | Year: 2017

Wetland mesocosms were constructed to assess two hybrid poplar clones (Populustrichocarpa × P. deltoides × P. nigra ‘345-1’ and ‘347-14’) for treating saline water high in boron (B) and selenium (Se), and a hydroponic experiment was performed to test the B tolerance and B accumulation in both clones. In the mesocosm experiment, clone 345-1 exhibited no toxic symptoms at an EC of 10 mS cm−1, while clone 347-14 showed slight toxic symptoms at 7.5 mS cm−1. The removal percentages of B, Se, sodium (Na), and chloride (Cl) ranged from 26.7–45.6%, 50–69.4%, 18.4–24.0%, and 15.8–23.2%, respectively, by clone 345-1, and from 22.9–29.4%, 31.7–43.8%, 16.5–24.2%, and 14.9–23.9%, respectively, by clone 347-1. In the hydroponic experiment, B toxic symptoms were observed at treatments of 150 and 200 mg B L−1 for clones 345-1 and 347-14, respectively. The greatest leaf B concentrations of 3699 and 1913 mg kg−1 were found in clone 345-1 and clone 347-14, respectively. The translocation factor (TF) of clone 347-14 was less than clone 345-1. Clone 345-1 only showed significantly greater (P < 0.05) B removal percentages than clone 347-14 when B treatment was <20 mg B L−1. In conclusion, both tested poplar clones competitively accumulated and removed B and Se in constructed wetlands. © 2017


Pang X.,University of York | Pang X.,CAS Changchun Northeast Institute of Geography and Agroecology | Lewis A.C.,University of York
Journal of Chromatography A | Year: 2013

We present a microfluidic lab-on-a-chip derivatization technique for the analysis of gaseous carbonyl compounds using O-(2,3,4,5,6-pentafluorobenzyl) hydroxylamine (PFBHA) as the derivatizing reagent. The novel microfluidic lab-on-a-chip derivatization technique has been developed to measure nmol per mole (ppbv) mixing ratios of gaseous carbonyl compounds, which are of particular importance to atmospheric chemistry. The technique utilised a planar glass microreactor comprising three inlets and one outlet, gas and fluid splitting and combining channels, mixing junctions, and a 2.0m long, 620μm internal diameter reaction microchannel. The microreactor integrated three functions, providing: (1) a gas and liquid mixer and reactor, (2) reagent heating, and (3) sample pre-concentration. The concentration of derivatization solution, the volumetric flow rates of the incoming gas sample and PFBHA solution, and the temperature of the microreactor were optimised to achieve a near real-time measurement. The enhanced phase contact area-to-volume ratio and the high heat transfer rate in the microreactor resulted in a fast and high efficiency derivatization reaction, generating an effluent stream which was ready for direct introduction to GC-MS. Good linearity was observed for eight carbonyl compounds over the measurement ranges of 1-500ppbv when they were derivatized under optimal reaction conditions. The method detection limits (MDLs) were below 0.10nmolmol-1 for most carbonyls in this study, which is below or close to their typical concentrations in clean ambient air. The performance of the technique was assessed by applying the methodology to the quantification of glyoxal (GLY) and methylglyoxal (MGLY) formed during isoprene photo-oxidation in an outdoor photoreactor chamber (EUPHORE). Good agreements between GLY and MGLY measurements were obtained comparing this new technique with Fourier Transform InfraRed (FTIR), which provides support for the potential effectiveness of the microfluidic technique for gaseous measurements. © 2013 Elsevier B.V.


Su S.,Zhejiang University | Jiang Z.,Minjiang University | Zhang Q.,Zhejiang University | Zhang Y.,CAS Changchun Northeast Institute of Geography and Agroecology
Applied Geography | Year: 2011

This paper analyzed the spatiotemporal dynamics of agricultural landscapes within Hang-Jia-Hu region (China) from 1994 to 2003 using a set of metrics that relate closely with sustainability. Considerable urban expansion was identified with the total built-ups increasing by 224.7% from 6.99 × 104 ha to 22.7 × 104 ha. The outcomes indicated that, at the whole region scale, agricultural landscapes became lost, fragmented, transformed and isolated as urbanization intensified. Global Moran's I statistics and Local Indicators of Spatial Association (LISA) analysis were employed to characterize the spatial dependence and hotspots for intra-level agricultural landscape changes at two grid scales. Generally, isolation of agricultural patches was a localized problem, while shape transformation of agricultural landscapes was a more regionalized problem; hotspots for lost, fragmentation and irregularity of agricultural landscapes concentrated around urban centers, while those for isolation of agricultural patches appeared in rural mountain areas. Spatial regression models further revealed that changes of agricultural landscapes showed diverging relationships with urbanization indicators for each landscape metric. The character and strength of relationships for each landscape metric were different and changed with scale. While our results of agricultural landscape changes consisted with some theoretical predictions in the literature, they also showed different spatiotemporal signatures of urbanization. Resolving these differences will certainly contribute to the ongoing landscape transformation and sustainability debate. This study demonstrated complexities of relationships between urbanization and agricultural landscape changes, and highlighted the importance of selected variables, spatial and temporal scales and incorporation of spatial dimensions when quantifying these relationships. © 2010 Elsevier Ltd.


Bu Y.,CAS Shanghai Institutes for Biological Sciences | Wu D.H.,CAS Changchun Northeast Institute of Geography and Agroecology
Florida Entomologist | Year: 2012

Chinese Yamatentomon is revised and Yamatentomon guoi sp. nov. is described from northeastern China. The new species is characterized by the extremely long sensillum b on foretarsus, short and slender A1 setae on tergites I-VII, presence of P3a on tergites IV-VII, 5 pairs of A-setae on tergite VII, and pore arrangement on tergites IV-VI. The new species is similar to Y. kunnepchupi Imadaté, 1964, but can be distinguished by the length of sensilla b and e on foretarsus, and chaetotaxy of tergites IV and V. DNA barcodes for the new species are provided to give a reference for identification in the future. In addition, Yamatentomon yamato (Imadaté & Yosii, 1956) was redescribed based on the specimens from type locality. An updated key to the world species of the genus was also provided.


Li L.,Indiana University – Purdue University Indianapolis | Song K.,Indiana University – Purdue University Indianapolis | Song K.,CAS Changchun Northeast Institute of Geography and Agroecology
Remote Sensing of Environment | Year: 2015

Phycocyanin primarily exists in freshwater cyanobacteria. Accurate estimation of low phycocyanin concentration (PC) is critical for issuing an early warning of potential risks of cyanobacterial population growth to the public. To monitor cyanobacterial biomass in eutrophic inland waters, an approach is proposed to partition non-water absorption coefficient (at-w(λ)) into the contribution of colored dissolved matter (CDM), non-phycocyanin pigments, and phycocyanin with the aim of improving the accuracy in remotely estimated PC, in particular for low PC. The proposed algorithm extends the IOP Inversion Model of Inland Waters (IIMIW) that derives at-w(λ) and chlorophyll-a concentration from remote sensing reflectance. The extended IIMIW retrieves absorption spectra of both CDM (acdm(λ)) and phytoplankton (aph(λ)) with R2≥0.80 and a relative root mean square error (rRMSE)≤31.79% for acdm(412), aph(443), aph(620), and aph(665) when validated with data collected in 2010 from three Indiana reservoirs. In fact, comparison of our algorithm with other partitioning models demonstrates the new algorithm to be more suitable for inland waters. The algorithm also achieved more accurate PC estimation with R2=0.81, rRMSE=33.60%, and mean relative error (RE)=49.11% than the widely used semi-empirical algorithm with R2=0.73, rRMSE=45.09%, and mean RE=182.29% for the same dataset. The validation of our algorithm against the data collected in other years shows that the proposed algorithm worked for a wide range of limnological conditions. In particular, low PC (PC≤50mgm-3) values of for all datasets used in this study were well predicted by the proposed algorithm. © 2014 Elsevier Inc.


Liu D.,CAS Changchun Northeast Institute of Geography and Agroecology | Zhang Z.-Q.,Landcare Research
Zootaxa | Year: 2013

The genus Austrophthiracarus (Acari: Oribatida: Phthiracaridae) was represented in New Zealand by four species prior to this work. In this paper, two new species of Austrophthiracarus are described from the South Island, New Zealand: Austrophthiracarus cronadun sp. nov. collected near Cronadun, Buller and Austrophthiracarus tawhai sp. nov. from Catlins State Forest, Otago. A key to all known species of Austrophthiracarus in New Zealand is provided. Copyright © 2013 Magnolia Press.


Liu D.,CAS Changchun Northeast Institute of Geography and Agroecology | Zhang Z.-Q.,Landcare Research
Systematic and Applied Acarology | Year: 2013

The genus Oribotritia (Acari: Oribatida: Oribotritiidae) was represented in New Zealand by six species prior to this work. In this paper, three species of Oribotritia from New Zealand are described, including two new species, Oribotritia mangamuka sp. nov. and Oribotritia bilaminae sp. nov., and a known species with some variation. A key to all known species of Oribotritia in New Zealand is also provided. © 2013 Systematic & Applied Acarology Society.


Su S.,Zhejiang University | Xiao R.,Zhejiang University | Zhang Y.,CAS Changchun Northeast Institute of Geography and Agroecology
Applied Geography | Year: 2012

Scientific interpretation of the relationships between agricultural landscape patterns and urbanization is important for ecological planning and management. Ordinary least squares (OLS) regression is the primary statistical method in previous studies. However, this global regression lacks the ability to uncover some local-specific relationships and spatial autocorrelation in model residuals. This study employed geographically weighted regression (GWR) to examine the spatially varying relationships between several urbanization indicators (urbanization intensity index, distance to urban centers and distance to road) and changes in metrics describing agricultural landscape patterns (total area, patch density, perimeter area ratio distribution and aggregation index) at two block scales (5 km and 10 km). Results denoted that GWR was more powerful than OLS in interpreting relationships between agricultural landscape patterns and urbanization, since GWR was characterized by higher adjust R2, lower Akaike Information Criterion values and reduced spatial autocorrelations in model residuals. Character and strength of the relationships identified by GWR varied spatially. In addition, GWR results were scale-dependent and scale effects were particularly significant in three aspects: kernel bandwidth of weight determination, block scale of pattern analysis, and window size of local variance analysis. Homogeneity and heterogeneity in the relationships between agricultural landscape patterns and urbanization were subject to the coupled influences of the three scale effects. We argue that the spatially varying relationships between agricultural landscape patterns and urbanization are not accidental but nearly universal. This study demonstrated that GWR has the potential to provide references for ecological planners and managers to address agricultural landscapes issues at all scales. © 2011 Elsevier Ltd.


Mao R.,CAS Shenyang Institute of Applied Ecology | Mao R.,CAS Changchun Northeast Institute of Geography and Agroecology | Zeng D.-H.,CAS Shenyang Institute of Applied Ecology
Geoderma | Year: 2012

Poplar leaf litter and crop residues (leaves and stems) of two main crops (soybean and maize) collected from semiarid agroforestry systems of Northeast China were used in our microcosm study. The aims were to examine whether non-additive effects (synergistic or antagonistic) between poplar leaf litter and crop residues exist during decomposition and to identify the influence of residue mixing proportion on the incidence of non-additive effects of residue mixture for the same plant residues. We determined residue decomposition rate by measuring mass loss and N release. Synergistic effects between poplar leaf litter and crop residues were more common than additive effects in terms of mass loss and N release. Moreover, the interactive effects between tree leaf litter and crop residues on decomposition varied with the number of component residues and their mixing proportion. Three-residue mixtures produced synergistic effects on mass loss and N release, although two-residue mixtures showed an additive effect in some cases. In addition, as compared with equal proportion, mixing residues with unequal proportion increased the incidence of non-additive effects during decomposition of residue mixture. These findings highlight that residue decomposition dynamics in ecosystems should be assessed on the basis of plant residue mixtures and their mixing proportions, which may help us better understand nutrient dynamics and guide our decisions on nutrient management. © 2011 Elsevier B.V.


Zhou D.W.,CAS Changchun Northeast Institute of Geography and Agroecology
Ying yong sheng tai xue bao = The journal of applied ecology / Zhongguo sheng tai xue xue hui, Zhongguo ke xue yuan Shenyang ying yong sheng tai yan jiu suo zhu ban | Year: 2011

Field survey and site study were conducted to approach the process and causes of salinization-alkalization of Leymus chinensis grassland in Songnen Plain, and to examine the hypothesis of soil disturbance-bareness. In the grassland, surface soil (0-30 cm) had a lower salt content, while deeper soil (> 30 cm) was in adverse. Thereby, the grassland was defined as soil-salted grassland. There was an increasing salt content in surface soil. This process was called as soil salinization-alkalization, and the grassland under the salinization:alkalization was named as alkali-salinized grassland. The leading reason for the surface soil salinization-alkalization was that the surface soil originally with low salt content was disturbed and lost away, subsurface soil rich in salt emerged as new surface soil, and the salt in deeper soil layers accumulated in the new surface soil and other soil layers. Secondary halophyte communities formed on the surface-soil-disturbed new bare land, but the communities had no succession sequence. The degradation process of the grassland was soil degradation first, followed by vegetation degradation, halophyte invasion, and successive evolution from nearly primitive condition.

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