基于多源数据的“安全公正空间”在大通湖流域环境管理中的应用

如何在确保生态系统安全的同时有效地开发和利用资源、保障人类福祉是当前面临的挑战。近年来兴起的“安全公正空间”(Safe and Just Operating Space, SJOS)理论框架为人类可持续发展提供了有效的评估方法, 即充分利用自然资源来提高人类社会福祉的同时确保环境生态安全。研究以长江中下游地区大通湖流域为例, 根据流域内的社会经济数据、环境监测数据和湖泊沉积记录, 从社会基础和环境系统两个方面构建该流域的SJOS框架, 并利用环境库兹涅兹曲线来揭示总体环境变化特征。结果表明: 流域内淡水利用、空气质量、水质均突破环境上限, 处于危险的状态, 此外流域内无贫困和产业创新两个社会基础维度的完成度相对较低。环境库兹涅兹曲线揭示了大通湖流域内社会-生态系统大致分为初始阶段(1950s—1980s)、严重退化阶段(1980s—2000s)和逐步改善(2000s后)三个阶段。研究为维持区域可持续发展提供了重要的参考信息, 同时也为区域SJOS框架的构建提供了一种有效的方法。     

中国生态功能保护区归一化植被指数动态及气候因子驱动

为揭示生态功能保护区归一化植被指数(NDVI)与气候因子相关性, 为今后该区域植被动态监测提供有用的信息, 该研究基于2000-2015年MODIS NDVI数据和逐月格点降水与气温数据, 采用生态功能保护区和像元两种空间尺度, 应用线性倾向分析、偏相关分析、复相关分析等方法研究了46个生态功能保护区NDVI变化及其与气候因子的关系, 在此基础上基于相关系数显著性水平对生态功能保护区NDVI动态进行了气候因子驱动分区。主要结果: (1)生态功能保护区NDVI总体呈增加趋势, 其增率加权平均值为0.045·a^-1。像元分析表明, NDVI显著增加的区域主要分布在中部和东北部。(2)生态功能保护区NDVI与降水的偏相关系数在-0.30-0.72之间, 在32个分区呈正相关关系。NDVI与气温的偏相关性在-0.36-0.92之间, 在39个分区呈正相关关系。像元分析表明, 50.6%的像元NDVI与降水呈显著正偏相关关系, 主要分布在东北及西北地区。64.6%的像元NDVI与气温呈显著正偏相关关系, 主要分布在东北及青藏高原北缘地区。(3)气温-降水强驱动型是主要驱动类型, 占总面积的38.7%; 气温驱动型为次要驱动类型, 占27.3%; 非气候因子驱动型占17.6%。以上结果表明, 生态功能保护区NDVI与气温、降水气候因子改变具有显著相关性, 气候因子驱动的地区共占82.4%。研究气候变暖背景下生态功能保护区NDVI变化及其对气候因子的响应, 对于认识该区植被动态变化规律具有重要作用。     

The dendroclimatic value of oak stable isotopes

Tree-ring stable oxygen and carbon isotope ratios (δ¹⁸O and δ¹³C) are an important archive for climate reconstructions. However, it remains unclear whether the polyvinyl acetate emulsion, often used for the preservation and fixation of wood samples, influences δ¹⁸O and δ¹³C signals. Further uncertainties are associated with the possible effects of geographical origin and cambial age of historical samples. Here, we present annually-resolved and absolutely-dated δ¹⁸O and δ¹³C measurements of 21 living oaks (Quercus robur and Q. petraea) from the Czech Republic. We find that the δ¹⁸O and δ¹³C signals in the extracted alpha-cellulose are not affected by polyvinyl acetate treatment. Covering the entire 20^th century and reaching until 2018 CE, our dataset reveals spatial and temporal coherency within and between the individual δ¹⁸O and δ¹³C chronologies of different oak species, sample locations, and tree ages. Highly significant (p < 0.01) Pearson’s correlation coefficients of the site-specific δ¹³C and δ¹⁸O chronologies range from 0.48–0.77 and 0.36–0.56, respectively. The isotopic inter-series correlations of Q. robur and Q. petraea from the same site are 0.75 and 0.43 for the mean δ¹³C and δ¹⁸O values, respectively. Significant (p < 0.01) correlations of 0.49 and 0.84 are found for δ¹³C and δ¹⁸O, respectively, when all measurements from all sampling locations and tree ages are included. Our study shows that non-pooled oak δ¹⁸O and δ¹³C measurements from both species, different locations, and diverse tree ages can be combined into robust isotopic chronologies for climate reconstructions.     

Competition and overlap of Oryzaephilus surinamensis and Plodia interpunctella populations under condition of stored date fruits

Plodia interpunctella and Oryzaephilus surinamensis are found in food storehouses including dates and palm storages. The current study aimed to determine competition and overlap potentials of the two pests of date fruits. Time series models were used to study two species populations and logistic growth model to estimate the effect of density of the species. The results revealed the environmental capacities of O. surinamensis and P. interpunctella were 433 and 1610 (maximum number per 20 g), respectively, and the population growth rates (r) were 1.2 and 1.3, respectively. Ecological balances of the two species were close to each other from the first to the third week. The population of O. surinamensis decreased in the fourth week of the competition. The highest population balance of the two species was in the 14th week. The potential of exploitable ecological niches (e_ij) and the amount of non-exploited ecological niches by any species (z_ij) for O. surinamensis was higher than for P. interpunctella from the 8th week untill the end of sampling period. The overlap of ecological niches in the two species (D) ranged from 0.94 to 1, indicating a complete overlap of temporal activity in the two populations on date palm. The current results of this study can be used by integrated pest management specialists. Information over the effects of species competition on population dynamics and their coexistence can be used to predict population status and to adopt simple pest control methods.     

Determination of material parameters of the two-dimensional Holzapfel–Weizsäcker type model based on uniaxial extension data of arterial walls

Soft tissues are anisotropic materials yet a majority of mechanical property tests have been uniaxial, which often failed to recapitulate the tensile response in other directions. This paper aims to study the feasibility of determining material parameters of anisotropic tissues by uniaxial extension with a minimal loss of anisotropic information. We assumed that by preselecting a certain constitutive model, we could give the constitutive parameters based on uniaxial extension data from orthogonal strip samples. In our study, the Holzapfel–Weizsäcker type strain energy density function (H–W model) was used to determine the material parameters of arterial walls from two fresh donation bodies. The key points we applied were the relationships between strain components in uniaxial tensile tests and the methods of stochastic optimisation. Further numerical experiments were taken. The estimate–effect ratio, defined by the number of data with the precision of estimation less than 0.5% over whole size of data, was calculated to demonstrate the feasibility of our method. The material parameters for Chinese aorta and pulmonary artery were given with the maximum root mean square (RMS) errors 0.042, and the minimal estimate–effect ratio in numerical experiments was 90.79%. Our results suggest that the constitutive parameters of arterial walls can be determined from uniaxial extension data, given the passive mechanical behaviour governed by H–W model. This method may apply to other tissues using different constitutive models.     

Azione della Cinetina sulla Degradazione della Clorofilla in Foglie di Orzo Irradiate

Abstract

The effects of kinetin on chlorophyll breakdown in irradiated barley leaves. — Kinetin is shown to inhibit the breakdown of chlorophyll in isolated barley leaves. Moreover the kinetin is shown to inhibit, even if with lower effect, the chlorophyll breakdown in irradiated barley leaves. This possible correlation of these observations, with kinetin promoted protein synthesis is suggested.     

Optimization of the hydrolysis of lignocellulosic residues by using radial basis functions modeling and particle swarm optimization

The concentrations of glucose and total reducing sugars obtained by chemical hydrolysis of three different lignocellulosic feedstocks were maximized. Two response surface methodologies were applied to model the amount of sugars produced: (1) classical quadratic least-squares fit (QLS), and (2) artificial neural networks based on radial basis functions (RBF). The results obtained by applying RBF were more reliable and better statistical parameters were obtained. Depending on the type of biomass, different results were obtained. Improvements in fit between 35% and 55% were obtained when comparing the coefficients of determination (R²) computed for both QLS and RBF methods. Coupling the obtained RBF models with particle swarm optimization to calculate the global desirability function, allowed to perform multiple response optimization. The predicted optimal conditions were confirmed by carrying out independent experiments.     

The SER primer and climate change

The SER Primer on Ecological Restoration provides a succinct introduction to, and overview of, the rapidly growing field of ecological restoration. The Primer was issued initially in 2002 by the Society for Ecological Restoration (SER) and reissued verbatim 2 years later in a more attractive format ( http://www.ser.org/resources;resources-detail-view/ser-international-primer-on-ecological-restoration ). A SER committee recently began deliberations to update the Primer, and much discussion is underway. As two of the Primer's principal authors, we were invited to share our views on how the Primer can be advantageously revised in the light of any changes or new insights since 2002. In particular, we were asked how the Primer might be modified to reflect the ways that ecological restoration address conservation issues raised by climate change and other rapid environmental shifts and global changes. We also touch on questions relating to the benefits of ecological restoration to human society, as this is an area where the Primer needs sharper focus. We have structured the following in a ‘Frequently Asked Questions’ format to highlight issues raised in the recent literature and to focus attention on other issues that merit consideration in the Primer revision process.