The progress of interdisciplinarity in invasion science

Interdisciplinarity is needed to gain knowledge of the ecology of invasive species and invaded ecosystems, and of the human dimensions of biological invasions. We combine a quantitative literature review with a qualitative historical narrative to document the progress of interdisciplinarity in invasion science since 1950. Our review shows that 92.4% of interdisciplinary publications (out of 9192) focus on ecological questions, 4.4% on social ones, and 3.2% on social–ecological ones. The emergence of invasion science out of ecology might explain why interdisciplinarity has remained mostly within the natural sciences. Nevertheless, invasion science is attracting social–ecological collaborations to understand ecological challenges, and to develop novel approaches to address new ideas, concepts, and invasion-related questions between scholars and stakeholders. We discuss ways to reframe invasion science as a field centred on interlinked social–ecological dynamics to bring science, governance and society together in a common effort to deal with invasions.     

汞分析仪直接测定土壤中总汞的方法研究

建立了利用RP91C-RA915M汞分析仪直接测定土壤中总汞的方法。该方法直接固体进样,省去了常规方法加酸消解、赶酸、定容等繁琐的前处理步骤;利用标准土壤绘制工作曲线,无需反复稀释标准储备液配制标准溶液,测定了方法检出限、精密度及准确度。结果表明此方法准确、可靠,是一个比较理想的分析方法。本方法的检出限为0.25μg/kg,相对标准偏差为1.98%~4.92%,标准样品测定准确,加标回收率为92.8%~106%。     

典型农耕区黑土和沼泽土团聚体颗粒中重金属的分布特征解析

了解重金属在土壤中的富集特征是其风险评价和土壤修复的基础。分别以黑龙江省典型的农耕黑土和沼泽土为研究对象,采用干筛法获得〉4000、4000～2000、2000～1000、1000～250、250～53和〈53衄16个粒级的土壤团聚体颗粒组。利用等离子质谱（ICP-MS）测定了本土和各级团聚体颗粒中Cr、Cd、As和Pb的含量,并对其颗粒组分布特征及对有机碳的响应进行了解析。研究表明,2种土壤中的重金属Cr、Cd和Pb的富集因子均大于1,而As则存在明显的流失。除了黑土中的As和Pb外,其他重金属随着团聚体粒径的增加而呈现富集减弱的趋势。其中,cr和cd主要趋向分布在粉．黏团聚体（〈53wn）颗粒中;Pb在黑土中易赋存于1000～2000μm大团聚体中,在沼泽土中则富集于53～250μm的微团聚体中;As不但趋向被吸附在53～250μm的微团聚体中,而且在黑土中也容易被吸附在〉l000μm的大团聚体中。金属质量负载计算表明,大粒径颗粒组对土壤中重金属含量的总体贡献较大。土壤中有机碳含量均随着团聚体粒径减小而升高,cr和Cd分布与颗粒有机碳含量正相关,黑土中As的分布与颗粒中有机碳含量负相关而在沼泽土中呈弱正相关,Pb的分布则与有机碳含量均无明显的相关性。     

Electrokinetic removal of chromium and copper from contaminated soils by lactic acid enhancement in the catholyte

The electrokinetic removal of chromium and copper from contaminated soils by adding lactic acid in cathode chamber as an enhancing reagent was evaluated. Two sets of duplicate experiments with chromium contaminated kaolinite and with a silty soil sampled from a supeffund site in Califomia of USA and polluted by Cr and Cu, were carried out in a constant current mode. Changes of soil water content and soil pH before and after the electrokinetic experiments, and variations of voltage drop and electroosmosis flow during the treatments were examined. The results indicated that Cr, spiked as Cr(Ⅵ) in the kaolinite, was accumulated mainly in the anode chamber, and some of Cr and metal hydroxides precipitated in the soil sections in contact with the cathode, which significantly increased electrical energy consumption. Treatment of the soil collected from the site showed accumulation of large amounts of Cr and Cu in the anode chamber while none was detected in the cathode one. The results suggested that the two metals either complexed with the injected lactic acid at the cathode or existed as negatively charged complex, and electromigrated toward the anode under a voltage gradient.     

Heavy metals pollution in poultry and livestock feeds and manures under intensive farming in Jiangsu Province, China

The heavy metals pollution in poultry and livestock feeds and manures under intensive farming in Jiangsu Province was investigated. 97 feed and manure samples were sampled from 31 farming plants in 10 major cities of Jiangsu. 14 metals, including Zn, Cu, Pb, Cd, Cr, Ni, Mo, Mn, Ba, Co, Sr, Ti, As and Hg, were analyzed after samples acid digestion. The results showed that the most feed samples contained high concentration of metals exceeding National Hygienical Standard for Feeds. Meanwhile, it was found that Cu, Zn, Pb, Cd and Cr concentrations in animal manures were also high, for example, Cu concentration in a manure sample reached to as much as 1726.3 mg/kg. Heavy metals loading quantities in soil per year were then calculated when metals contaminated organic fertilizers were applied, and its effects on soil environmental qualitv were further evaluated.     

手性氟虫腈对意大利蜜蜂和稻螟赤眼蜂的急性毒性及安全评价

手性农药多以外消旋体形式用于农业生产和卫生害虫防治中。但手性农药对映体通常具有不同的生物活性和毒性,这种现象在农药环境风险评价过程中往往被忽视。本研究以氟虫腈为例,首先用高效液相色谱-手性固定相(HPLC-CSP)技术拆分出氟虫腈的S型和R型2种对映体,分别采用点滴法和药膜法测定了氟虫腈对映体及外消旋体对意大利蜜蜂(Apis mellifera L.)和稻螟赤眼蜂(Trichogramma japonicum Ashmead)的急性毒性。结果显示,S(+)-氟虫腈、R(-)-氟虫腈和外消旋体对意大利蜜蜂的48h-LD50分别为0.00341、0.00396和0.00383μg·蜂-1,对稻螟赤眼蜂的24h-LR50分别为7.56×10-7、8.06×10-7和7.29×10-7mg·cm-2。研究表明,氟虫腈对意大利蜜蜂具有高毒性风险,对稻螟赤眼蜂有极高毒性风险,且氟虫腈对意大利蜜蜂和稻螟赤眼蜂的急性毒性无明显的对映体选择性。因此,使用氟虫腈单一对映体不会降低其对环境生物的毒害风险。     

Forecasting population trend from the scaling pattern of occupancy

Forecasting the temporal trend of a focal species, its range expansion or retraction, provides crucial information regarding population viability. To this end, we require the accumulation of temporal records which is evidently time consuming. Progress in spatial data capturing has enabled rapid and accurate assessment of species distribution across large scales. Therefore, it would be appealing to infer the temporal trends of populations from the spatial structure of their distributions. Based on a combination of models from the fields of range dynamics, occupancy scaling and spatial autocorrelation, here I present a model for forecasting the population trend solely from its spatial distribution. Numerical tests using cellular automata confirm a positive correlation, as inferred from the model, between the temporal change in species range sizes and the exponent of the power-law scaling pattern of occupancy. The model is thus recommended for rapid estimation of species range dynamics from a single snapshot of its current distribution. Further applications in biodiversity conservation could provide a swift risk assessment, especially, for endangered and invasive species.     

Does the self-similar species distribution model lead to unrealistic predictions?

J. Harte et al. demonstrated that the power law form of the species-area relationship may be derived from a bisected, self-similar landscape and a community-level probability rule. Harte's self-similarity model has been widely applied in modeling species distributions. However, R. D. Maddux showed that this self-similarity model generates biologically unrealistic predictions. We resolve the Harte-Maddux debate by demonstrating that the problems identified by Maddux result from an assumption that the probability of occurrence of a species at one scale is independent of its probability of occurrence at the next. We refer to this as a "non-heritage assumption." By altering this assumption to one in which each species in the community has an occupancy status that is partially inherited across scales (a scale-heritage assumption), the predictions of the self-similarity model are neither mathematically inconsistent nor biologically unrealistic. Harte's self-similarity model remains an important framework for modeling species distributions. Our results illustrate the importance of considering patterns of species co-occurrence, and the way in which species occupancy patterns change with scale, when modeling species distributions.     

染料酸性橙Ⅱ生产废水处理工艺

以天津某染化厂的酸性橙Ⅱ废水为研究对象,利用Ｎ₂₃₅-煤油－Ｈ₂ＳＯ₄－ＮａＯＨ的萃取－反萃取体系,通过静态杯皿实验,确定了萃取－反萃取过程的最佳工艺参数,使萃取效率可达９０％ ,出水ＣＯＤ值可降低到３５０ｍ ｇ／Ｌ;酸性橙Ⅱ废水的有机成分总浓缩倍数达２５～４０倍;废水的萃余液经二次萃取法和混凝沉淀法处理后,出水的ＣＯＤ值＜ ２００ｍ ｇ／Ｌ,色度＜ ８０倍,达到天津市工业废水的排放标准     

Electrokinetic remediation of a Cu contaminated red soil by conditioning catholyte pH with different enhancing chemical reagents

The effect of enhancement reagents on the efficiency of electrokinetic remediation of Cu contaminated red soil is evaluated. The enhancement agents were a mix of organic acids, including lactic acid+NaOH, HAc-NaAc and HAc-NaAc+EDTA. The soil was prepared to an initial Cu concentration of 438 mgkg(-1) by incubating the soil with CuSO4 solution in a flooded condition for 1 month. Sequential extraction showed that Cu was partitioned in the soil as follows: 195 mgkg(-1) as water soluble and exchangeable, 71 mgkg(-1) as carbonate bound and 105 mgkg(-1) as Fe and Mn oxides. The results indicate that neutralizing the catholyte pH maintains a lower soil pH compared to that without electrokinetic treatment. The electric currents varied depending upon the conditioning solutions and increased with an increasing applied voltage potential. The electroosmotic flow rate changed significantly when different conditioning enhancing reagents were used. It was observed that lactic acid+NaOH treatments resulted in higher soil electric conductivities than HAc-NaAc and HAc-NaAc+EDTA treatments. Ultimately, enhancement by lactic acid+NaOH resulted in highest removal efficiency (81% Cu removal) from the red soil. The presence of EDTA did not enhance Cu removal efficiencies from the red soil, because EDTA complexed with Cu to form negatively charge complexes, which slowly migrated toward the anode chamber retarding Cu2+ transport towards the cathode.