Selection of poly(R)-3-hydroxybutyric acid utilising bacteria by enrichment,optimisation and compatibility testing for consortia development

Bacterial strains with poly-3-hydroxybutyrate (PHB) degradation potential were isolated from waste yard soil samples of selected industrial sites in Uttarakhand, India, and two microbial consortia were developed, i.e. Consortium I comprises Pseudomonas sp. strain Rb10, Pseudomonas sp. strain Rb11 and Bacillus sp. strain Rb18, and Consortium II is composed of Lysinibacillus sp. strain Rb1, Pseudomonas sp. strain Rb13 and Pseudomonas sp. strain Rb19. The current study involved enrichment selection via liquid and semi-solid media, followed by isolation and screening of bacterial strains using PHB pellets and films. Furthermore, the identification and characterisation was done by triphasic approach. The utilisation of PHB by the characterised strains was confirmed by Fourier transform infrared spectroscopy and scanning electron microscopy. Moreover, the minimum inhibitory concentration of solubilised PHB was found to be 2.5?mg/mL, which was detected through ‘clear zone assay’. Further, the selection and biocompatibility testing of potential isolates were performed for the formation of bacterial consortia. Thus, the present work would provide direct and standardised protocol for screening and selection of potential microbiomes for biodegradation of polymers by overcoming the negative effect of organic solvents. Moreover, indigenously developed consortia would be evaluated for their in situ biodegradation potential against various bioplastic films.     

北京西山国家森林公园中空气负离子浓度与气象因子的相关性研究

空气负离子(Negative air ions,NAI)是城市空气质量的重要指标之一,揭示城市森林释放NAI的影响机制,有助于充分利用NAI的净化作用及保健作用,并判断空气质量。利用北京西山国家森林公园2017年9月-2018年8月的NAI和气象数据,深入探究不同季节条件下和典型天气下影响空气负离子浓度(NAIC)的气象因素。结果显示,(1)不同季节条件下,NAI与气象因素相关关系不同。当温度在15℃以上时,NAIC与温度呈负相关;在15℃以下时,NAIC与温度呈正相关。多数情况下,NAIC与湿度呈反比,冬季湿度对NAIC负效应影响最明显(r=-0.503,P<0.01)。春秋冬NAIC与太阳辐射、气压均呈显著正相关关系,而夏季空气负离子与二者呈现负相关关系。(2)典型天气下,城市森林NAIC与晴天相比出现不同程度的差异,且与气象因子的相关性也不同。雨天条件下,NAIC日均值为2134ion·cm^-3,比晴天NAIC高4.56%,主要受温度和降雨量的共同影响;雾霾天与冬季晴天相比,晴天昼间NAIC为2075 ion·cm^-3,雾霾天昼间NAIC为1948 ion·cm^-3,主要受太阳辐射量的影响;大风天气下NAIC峰值比微风天气高5.37%,日均值大于微风天气,主要受气压的影响。     

三江源国家公园自然资源资产管理体制改革实践与经验研究

健全全民所有自然资源资产管理体制,是实现自然资源资产合理使用和有效保护、发挥社会主义公有制优势、推动生态文明建设的重要举措.提炼三江源国家公园在自然资源资产管理体制改革过程中的典型实践,梳理其改革经验与启示,为探索建设以国家公园为代表的自然保护地体系内自然资源资产管理积累"青海经验"、做出"青海贡献".     

猫儿山自然保护区森林群落垂直格局与主导因素分析

陆地生态系统中海拔高度的变化会导致植物群落的垂直性分布,这是形成植物多样性的一个重要性原因。了解和分析不同区域植物群落的垂直性分布规律和生物多样性形成机制对保护森林生物多样性具有重要意义。本文通过对猫儿山自然保护区不同海拔高度森林植物群落和环境因子的调查,运用双向指示种分析（Two-way Indicator-Species Analysis）和典范对应分析（Canonical Correspondence Analysis）,对不同海拔高度的群落进行划分,对决定植物群落分布的主导环境因子进行分析,结果表明：（1）猫儿自然保护区森林群落可以分为7个群落类型,其代表树种分别是罗浮栲Castanopsis fabri、栲树Castanopsis fargeisii、银木荷Schima argentea、铁椎栲Castanopsis lamontii、南方铁杉Tsuga chinensis、长苞铁杉Tsuga longibracterata、马尾松Pinus massoniana;（2）在中亚热带,海拔对山地植物群落形成起决定性作用;（3）土壤是仅次于海拔的重要环境因子,其中土类和土层厚度对森林群落的影响较大。在中亚热带森林生态保护和恢复过程中,按照不同海拔高度的植物群落特征选择种植合适树种,按照当地土壤条件选择适当的生态保护和恢复措施能加快生态恢复的进程,提高生态保护的效益。     

Hunting, law enforcement, and African primate conservation

Abstract: Primates are regularly hunted for bushmeat in tropical forests, and systematic ecological monitoring can help determine the effect hunting has on these and other hunted species. Monitoring can also be used to inform law enforcement and managers of where hunting is concentrated. We evaluated the effects of law enforcement informed by monitoring data on density and spatial distribution of 8 monkey species in Taï National Park, Côte d’Ivoire. We conducted intensive surveys of monkeys and looked for signs of human activity throughout the park. We also gathered information on the activities of law‐enforcement personnel related to hunting and evaluated the relative effects of hunting, forest cover and proximity to rivers, and conservation effort on primate distribution and density. The effects of hunting on monkeys varied among species. Red colobus monkeys (Procolobus badius) were most affected and Campbell's monkeys (Cercopithecus campbelli) were least affected by hunting. Density of monkeys irrespective of species was up to 100 times higher near a research station and tourism site in the southwestern section of the park, where there is little hunting, than in the southeastern part of the park. The results of our monitoring guided law‐enforcement patrols toward zones with the most hunting activity. Such systematic coordination of ecological monitoring and law enforcement may be applicable at other sites.     

黏胶基活性炭纤维对三氯一氟甲烷的吸附性能

采用动态吸附试验,利用自制的试验装置研究了黏胶基活性炭纤维〔Viscose-Based Activated Carbon Fibre (Viscose-Based ACF)〕对三氯一氟甲烷(CFC-11)气体的吸附效果. 在进口ρ(CFC-11)为0.5～8.0 mg/L,空塔气速为0.2 m/s,气体体积流率为0.72 m3/h的条件下,计算出黏胶基活性炭纤维对CFC-11气体的吸附,容量为0.788 g/g,传质区高度为0.077 2 m,全床层饱和度为65.47%,并作出活性炭纤维(AFC)的穿透曲线. 用Freundlich方程对等温吸附曲线进行拟合显示,进口ρ(CFC-11)在0.5～8.0 mg/L时,Freundlich方程较好地拟合了等温吸附曲线,且便于实际计算.      

Screening and identification of bacterial strain producing (R)-1-phenyl-1,2-Ethanediol by efficient whole-cell catalytic reduction system北大核心CSCD

(R)-1-Phenyl-1,2-ethanediol [(R)-PED] is an important chiral intermediate used to synthesize pharmaceutical intermediates. The production of (R)-PED is of great practical significance. A novel bacterial strain HBU-SI7 isolated from soil samples was screened using a-hydroxyacetophenone (2-HAP) as substrate, which is capable of enantioselective reduction of 2-HAP to (R)-PED. HBU-SI7 was identified as Rhodococcus sp. by bacterial morphological observation and 16S rDNA analysis. The analysis of whole-cell catalytic system showed that the bioconversion of 2-HAP reached 96.2% in the two-phase reaction system (dibutyl phthalate/phosphate buffer = 1/3, V/V) with the substrate concentration of 3.0 g/L, and 99.3% of e.e. for (R)-PED was achieved. A new enantio selective reduction system with the whole cells of Rhodococcus sp. was established for efficient production of (R)-PED, which has potential research and application values. © 2018 Science Press. All rights reserved.     

Effects of Forest Fragmentation and Habitat Degradation on West African Leaf-Litter Frogs

Abstract:  Habitat degradation alters the dynamics and composition of anuran assemblages in tropical forests. The effects of forest fragmentation on the composition of anuran assemblages are so far poorly known. We studied the joint influence of forest fragmentation and degradation on leaf-litter frogs. We specifically asked whether the processes structuring leaf-litter anuran assemblages in fragmented forests are the same as those in continuous forests. We analyzed anuran assemblages with respect to habitat characteristics, including fragmentation and degradation parameters. In comparison with continuous forests, species richness and diversity were lower and assemblage composition was altered in forest fragments. These changes seemed to be mainly caused by habitat degradation rather than forest fragmentation. Availability of aquatic sites for breeding, vegetation structure (including those variables indicating degradation), and leaf-litter cover had the most influence on the presence of single species. The comparatively small impact of fragmentation on anurans might be due to the location of the study area; it still possessed large tracts of continuous forest. These forest blocks may stabilize the regional rainforest climate and thus weaken the effects of fragmentation .     

Allowing macroalgae growth forms to emerge: Use of an agent-based model to understand the growth and spread of macroalgae in Florida coral reefs,with emphasis on Halimeda tuna

The growth patterns of macroalgae in three-dimensional space can provide important information regarding the environments in which they live, and insights into changes that may occur when those environments change due to anthropogenic and/or natural causes. To decipher these patterns and their attendant mechanisms and influencing factors, a spatially explicit model has been developed. The model SPREAD (SPatially-explicit Reef Algae Dynamics), which incorporates the key morphogenetic characteristics of clonality and morphological plasticity, is used to investigate the influences of light, temperature, nutrients and disturbance on the growth and spatial occupancy of dominant macroalgae in the Florida Reef Tract. The model species, Halimeda and Dictyota spp., are modular organisms, with an “individual” being made up of repeating structures. These species can also propagate asexually through clonal fragmentation. These traits lead to potentially indefinite growth and plastic morphology that can respond to environmental conditions in various ways. The growth of an individual is modeled as the iteration of discrete macroalgal modules whose dynamics are affected by the light, temperature, and nutrient regimes. Fragmentation is included as a source of asexual reproduction and/or mortality. Model outputs are the same metrics that are obtained in the field, thus allowing for easy comparison. The performance of SPREAD was tested through sensitivity analysis and comparison with independent field data from four study sites in the Florida Reef Tract. Halimeda tuna was selected for initial model comparisons because the relatively untangled growth form permits detailed characterization in the field. Differences in the growth patterns of H. tuna were observed among these reefs. SPREAD was able to closely reproduce these variations, and indicate the potential importance of light and nutrient variations in producing these patterns.     

旅游对张家界国家森林公园土壤酶及微生物作用强度的影响

为了探明旅游对张家界国家森林公园土壤生物性状的影响,为保护土壤生态平衡,合理开发生态旅游提供理论依据,进行了旅游人为踩踏对土壤酶及微生物作用强度的影响研究。结果表明:背景区土壤的酶活性>缓冲区土壤的酶活性>活动区土壤的酶活性。背景区土壤的氨化作用强度与微生物活度>缓冲区土壤的氨化作用强度与微生物活度>活动区土壤的氨化作用强度与微生物活度,而硝化作用强度的变化则正相反。旅游显著影响了0～5cm土壤的酶活性及微生物作用强度;在5～15cm土壤和15～25cm土壤层中,背景区和缓冲区的酶活性和微生物作用强度差异不显著,而与活动区的差异显著。有机质分解相关的微生物氨化作用强度、纤维素酶活性、木聚糖酶活性、蛋白酶活性的影响主要是由于土壤有机质的投入减少而造成,而硝化作用强度则主要与踩踏引起的土壤板结造成亚硝酸盐的积累有关,踩踏严重,硝化作用强度大。不同土壤层的微生物作用强度及酶活性强弱是:0～5cm土壤>5～15cm土壤>15～25cm土壤。张家界国家森林公园土壤微生物作用强度及酶活性受到了人为踩踏的破坏,生态系统抵御外界干扰的能力也受到了旅游活动的破坏。