An economic evaluation framework for land-use-based conservation policy instruments in a changing climate

Climate change is a key threat to biodiversity. To conserve species under climate change, ecologists and conservation scientists suggest 2 main conservation strategies regarding land use: supporting species’ range shifts to enable it to follow its climatic requirements by creating migration pathways, such as corridors and stepping stones, and conserving climate refugia (i.e., existing habitat areas that are somewhat buffered from climate change). The policy instruments that could be used to implement these conservation strategies have yet to be evaluated comprehensively from an economic perspective. The economic analyses of environmental policy instruments are often based on ecological effectiveness and cost-effectiveness criteria. We adapted these general criteria to evaluate policy instruments for species’ conservation under climate change and applied them to a conceptual analysis of land purchases, offsets, and conservation payments. Depending on whether the strategy supporting species’ range shifts or conserving climate refugia is selected, the evaluation of the policy instruments differed substantially. For example, to ensure ecological effectiveness, habitat persistence over time was especially important for climate refugia and was best achieved by a land-purchase policy instrument. In contrast, for the strategy supporting range shifts to be ecologically effective, a high degree of flexibility in the location of conserved sites was required to ensure that new habitat sites can be created in the species’ new range. Offset programs were best suited for that because the location of conservation sites can be chosen comparatively freely and may also be adapted over time.     

GPRS在污水处理中的应用

介绍了将GPRS应用于污水处理行业中的好处,采用GPRS无线猫以无线的方式传输数据的优势：资费便宜,计费合理,设备投资低,新增和改变网点非常方便,线路稳定,接入速度快,而且永远不会掉线.最好地支持了频繁的或少量突发型的数据业务.     

兽药抗生素对土壤微生物群落的影响

兽药抗生素广泛应用于畜禽养殖业,用于预防、治疗动物疾病及促进动物生长。然而,养殖过程中使用的抗生素不能被动物完全吸收,其中40%～90%以母体或其代谢物的形式排出动物体外并随畜禽粪便进入土壤环境,对土壤微生物群落结构和功能产生影响。在汇总了畜禽粪便和土壤中兽药抗生素的残留特征之后,概述了抗生素对土壤微生物群落结构和功能的影响以及微生物产生的污染诱导群落耐性。重点探讨了抗生素微生物毒性的影响因素和近年来对微生物共耐性方面的研究,并对未来的研究方向及目标提出了建议。     

Efficient species-level monitoring at the landscape scale

Monitoring the population trends of multiple animal species at a landscape scale is prohibitively expensive. However, advances in survey design, statistical methods, and the ability to estimate species presence on the basis of detection-nondetection data have greatly increased the feasibility of species-level monitoring. For example, recent advances in monitoring make use of detection-nondetection data that are relatively inexpensive to acquire, historical survey data, and new techniques in genetic evaluation. The ability to use indirect measures of presence for some species greatly increases monitoring efficiency and reduces survey costs. After adjusting for false absences, the proportion of sample units in a landscape where a species is detected (occupancy) is a logical state variable to monitor. Occupancy monitoring can be based on real-time observation of a species at a survey site or on evidence that the species was at the survey location sometime in the recent past. Temporal and spatial patterns in occupancy data are related to changes in animal abundance and provide insights into the probability of a species' persistence. However, even with the efficiencies gained when occupancy is the monitored state variable, the task of species-level monitoring remains daunting due to the large number of species. We propose that a small number of species be monitored on the basis of specific management objectives, their functional role in an ecosystem, their sensitivity to environmental changes likely to occur in the area, or their conservation importance.     

The performance of state-of-the-art modelling techniques depends on geographical distribution of species

We explored the effects of prevalence, latitudinal range and clumping (spatial autocorrelation) of species distribution patterns on the predictive accuracy of eight state-of-the-art modelling techniques: Generalized Linear Models (GLMs), Generalized Boosting Method (GBM), Generalized Additive Models (GAMs), Classification Tree Analysis (CTA), Artificial Neural Network (ANN), Multivariate Adaptive Regression Splines (MARS), Mixture Discriminant Analysis (MDA) and Random Forest (RF). One hundred species of Lepidoptera, selected from the Distribution Atlas of European Butterflies, and three climate variables were used to determine the bioclimatic envelope for each butterfly species. The data set consisting of 2620 grid squares 30′ × 60′ in size all over Europe was randomly split into the calibration and the evaluation data sets. The performance of different models was assessed using the area under the curve (AUC) of a receiver operating characteristic (ROC) plot. Observed differences in modelling accuracy among species were then related to the geographical attributes of the species using GAM. The modelling performance was negatively related to the latitudinal range and prevalence, whereas the effect of spatial autocorrelation on prediction accuracy depended on the modelling technique. These three geographical attributes accounted for 19–61% of the variation in the modelling accuracy. Predictive accuracy of GAM, GLM and MDA was highly influenced by the three geographical attributes, whereas RF, ANN and GBM were moderately, and MARS and CTA only slightly affected. The contrasting effects of geographical distribution of species on predictive performance of different modelling techniques represent one source of uncertainty in species spatial distribution models. This should be taken into account in biogeographical modelling studies and assessments of climate change impacts.     

Screening bamboo species for salt tolerance using growth parameters,physiological response and osmolytes accumulation as effective indicators

Bamboos are potential species for reclamation of saline soils and water. In this study, the performances of three bamboo species, namely Dendrocalamus strictus (S1), Dendrocalamus longispathus (S2) and Bambusa bambos (S3), were investigated for salinity stress tolerance. After 14 days of treatment with 100?mM NaCl, reduction in shoot length was 66%, 100%, 77%, root length was 77%, 100%, 57%, number of leaves was 50%, 100%, 73% and fresh weight was 30%, 72%, 14% in S1, S2 and S3 species, respectively. Relative water content (RWC) in S1 and S3 species was 1.26 and 1.07 folds higher in 50?mM NaCl in comparison to control. In S2 species, total chlorophyll, chlorophyll_a and chlorophyll_b degradation were the highest (40.4%, 42.7%, 16.32%, respectively) in comparison to S3 (18.18%, 23%, 16.4%) and S1 (23.5%, 25%, 19.17%) species. In S3 and S1 species, the Chl_a/Chl_b ratio was maintained showing stabilisation of the net photosynthetic rate. Proline played a more important role than glycine betaine for salt tolerance of these bamboo species. On account of vegetative growth, proline accumulation and RWC, it is inferred that S1 and S3 species are salt tolerant while S2 is a sensitive species.

Abbreviations: SL: shoot length; RL: root length; NL: number of leaves; FW: fresh weight; RWC: relative water content; Chl_a: chlorophyll_a; Chl_b: chlorophyll_b; TC: total chlorophyll; GB: glycine betaine     

盐胁迫下八宝景天不同生态型对土壤中Cd积累特征

采用Cd含量为2.22 mg·kg^-1的潮褐土开展盆栽试验,通过外源添加NaCl研究不同生态型八宝景天对Cd和盐分复合胁迫的生长响应以及Cd吸收积累的差异.结果表明,在Cd单一或与盐分复合胁迫下,八宝景天各生态型间地上部生物量和Cd含量均表现出显著差异,盐分胁迫进一步加剧了八宝景天的生长抑制,高盐胁迫下八宝景天各生态型地上部Cd含量总体呈下降趋势,这与盐分引起土壤pH显著升高导致Cd生物有效性降低有关.此外,不同生态型对盐分胁迫表现出的生长和Cd吸收响应有显著差异,LN生态型地上部生物量在各处理下均显著高于其他生态型,且在1% NaCl处理下生物量仍没有显著下降,耐性指数可达0.91.同时,其地上部Cd含量在不同处理下均显著高于其他生态型,其原因为LN生态型在Cd富集和解毒的生理机制方面更具优势,而这些同样是其耐盐性的重要生理机制.综上可知,尽管盐分胁迫减少了八宝景天地上部Cd富集量,但其不同生态型间差异显著,LN生态型在2% NaCl处理下地上部Cd富集量仍可达84.4 μg·plant^-1,且较其他生态型显著提高48.4%~89.3%,因此,LN生态型八宝景天具有应用于修复盐渍化土壤Cd污染的潜力.     

泛比电阻电除尘器伏安特性的理论及实验研究

粉尘比电阻是影响电除尘器收尘效率的一个重要因素,为扩展电除尘器对粉尘比电阻的适应范围,提高对泛比电阻粉尘的收尘效率,提出一种具有辅助电极和交错平板收尘极的新型电除尘器,并对其伏安特性进行了研究。结果表明,泛比电阻电除尘器的收尘场强比普通的线-板式电除尘器高,而且更均匀,辅助电极对电晕电流具有明显的抑制作用。     

燃气爆炸荷载下隧道砌体损伤规律与事故影响范围研究

为降低隧道内燃气爆炸时砖砌体抛射物造成人员伤亡的概率,以中缅油气管道隧道砖砌体为研究对象,建立3种不同类型砖砌体的数值模型,将燃气爆炸荷载简化为三角形荷载,基于LS-DYNA软件,研究燃气爆炸荷载下隧道砖砌体结构的损伤规律与砖砌体抛射物的潜在影响范围.研究结果表明:砖砌体在天然气爆炸荷载作用下,可能会发生整体破坏,产生...