粤北山区社会-生态-经济系统恢复力及其协调度

[目的] 对粤北山区5市的社会—生态—经济系统的恢复力进行测度和协调度评价，为欠发达地区的可持续发展提供理论基础。[方法] 以恢复力的视角构建了社会—生态—经济耦合系统的理论框架和评价体系，并建立二元和三元协调度模型。[结果] ①社会—经济—生态系统恢复力总体上升，社会子系统和经济子系统恢复力增速较为缓慢，生态子系统恢复力有所下降；②社会—经济—生态系统恢复力等级空间明显，社会子系统恢复力等级升高，呈现“四周高中间低”的特点，经济系统恢复力呈现出“东高西低”的特征，生态子系统恢复力等级出现了下降的趋势。③生态—经济系统濒临失调，社会—生态系统基本协调，社会—经济系统初级协调；社会—生态—经济系统协调度仍然处于轻度失调阶段。[结论] 粤北地区耦合系统的恢复力有待提高，特别是生态系统恢复力。后期应该注重社会—生态—经济系统的协调和和互动能力。     

基于GIS的湖南省滑坡灾害风险和损失评估

[目的] 评估湖南省滑坡发生的风险和损失等级，丰富湖南省滑坡防治理论及方法，为该地减少滑坡灾害提供科学依据。[方法] 基于GIS技术和层次分析法（AHP）以DEM、遥感、气象、岩性、地震点等数据为支撑，分别从危险性评价和易损性评价两方面对湖南省滑坡风险进行评估。[结果] ①湖南省滑坡风险等级大多处于中低风险等级，少部分为较高风险或高风险等级，中度风险等级最多，占全省面积的31.31%，其余依次为较低、较高、低和高风险等级，其比例分别是24.92%，22.09%，13.88%和7.79%；②从空间格局来看，风险性等级整体呈现出中部、东南高，西南、东北低的空间分布特征；③湖南省滑坡损失等级整体呈现出东高西低，局部不均匀的分布特征。[结论] 湖南省滑坡灾害的管理主要应从预防和整治两方面进行，依据各地区常见滑坡类型，制定有针对性的区域差异化防治预案。     

区域自然灾害的社会脆弱性评估——以河南省为例

脆弱性研究对区域防灾减灾规划和灾害风险管理具有极其重要的作用。以灾害频发的河南省为研究区,以区内各地市为基本评价单元,运用秩次相关分析和PCA法筛选出11个相互独立的影响因子,构建了河南省自然灾害社会脆弱性评估模型。利用AHP法确定各指标的相对权重,采用综合指数法对各评价单元的社会弱性进行了评估,并借助ArcGIS软件对评估结果进行了区划制图研究。结果表明:(1)河南省自然灾害的社会脆弱性呈现出一定的地域分布规律。(2)周口市、商丘市和驻马店市社会脆弱性等级为Ⅲ,属高脆弱区;郑州市、济源市与三门峡市自然灾害的社会脆弱性等级为Ⅰ,属低脆弱区;其他地市评价等级为Ⅱ,属中等脆弱区。(3)全省所处高、中和低社会脆弱性的面积比例分别为22.68%,65.35%和11.97%。     

黄河河南段流域洪灾的社会脆弱性评价

[目的] 分析黄河河南段流域洪灾的社会脆弱性,为河南省沿黄区域的防洪救灾能力建设和风险管理提供科学依据。[方法] 以黄河流域河南段沿岸的7个地级市、1个省（管）市作为评价单元,从敏感性和社会应对水平两个维度选取了16个评价指标,并运用变异系数法确定指标权重,通过构建洪灾社会脆弱性模型,得出各评价单元的敏感性、社会应对水平和社会脆弱性指数。[结果] ①根据敏感性和社会应对水平指数特征,将河南段沿岸分为3种类型：低敏感性—低应对水平（濮阳、三门峡、济源、焦作市）;高敏感性—低应对水平（开封、新乡市）;高敏感性—高应对水平（洛阳、郑州市）;②开封、濮阳市洪灾社会脆弱性等级为Ⅲ;洛阳、郑州市洪灾社会脆弱性等级为Ⅰ;其余区域等级为Ⅱ;③从空间分布上来看,高社会脆弱性区域主要分布于黄河河南段流域的下游地区,中上游区域除洛阳、郑州市外都属于中等脆弱性区,整体处于中低脆弱性水平。[结论] 洪灾社会脆弱性较高的区域主要是由于社会应对水平较低,对防灾减灾能力建设投入不够所造成。     

低山丘陵区暴雨洪水特征与洪灾风险评估——以赣江上游为例

[目的]评估赣江上游洪灾风险,为区域减灾及社会经济发展提供参考。[方法]从气候和地形等自然条件出发,结合实测资料分析暴雨洪水时空特征;采用层次分析法确定致灾因子危险性、孕灾环境敏感性、承灾体的易损性和防洪救灾能力4个因子的14个指标的权重,借助GIS平台进行风险因子分析和综合风险评估。[结果]暴雨洪水多集中在3—7月,春夏季暴雨频次占全年的80.4%,洪水频次占95.9%,空间上主要分布在东北大部;致灾因子危险性风险等级东北部高,西部较低;孕灾环境敏感性风险呈带状,总体上中间高四周低;承灾体易损性风险中西,中北部高,四周低;防洪救灾能力西高东低,南高北低,从西南向东北递减;综合风险为中北部、中东部高风险,东南部、西部低风险;各风险等级面积比例存在差异,高风险和较高风险面积占比达37.3%。[结论]研究区暴雨洪水特征兼具丘陵与平原型特征,暴雨和洪水存在较明显的正相关关系;洪灾风险评估结果与赣江上游区实际基本符合,验证了指标体系及评估模型合理性。     

河南省城市化与生态环境耦合协调状态的时空格局

[目的] 探索河南省城市化与生态环境耦合协调状态的空间聚集特征,提出相关的发展建议,为河南省城市可持续发展提供科学的参考。[方法] 通过构建城市化与生态环境评价体系,利用改进的耦合协调度模型,研究2008—2018年河南省城市化与生态环境发展水平及耦合协调度,对河南省17个地级城市耦合协调度进行时空格局分析。[结果] 2008—2018年全省耦合度值都在0.9以上,耦合协调度呈波动上升趋势;多数城市的城市化水平低于生态环境水平,各市城市化与生态环境的耦合协调度等级有基本不协调、基本协调、协调、高级协调;城镇化与生态环境耦合协调存在空间正相关性,有西部和中部耦合协调度高、东南部耦合协调度低的聚类特征。[结论] 河南省整体城镇化进程加快,经济城市化和生态环境压力分别对城市化和生态环境两大系统产生了重要影响。应加强郑州市中心城市的发展,推动河南东南部城市的发展。     

基于层次分析法的豫北地区雨水花园植物综合评价

[目的]研究豫北地区雨水花园植物的筛选,为雨水花园和海绵城市的建设提供理论支撑。[方法]对国家级海绵城市鹤壁市和河南省省级海绵城市安阳市境内的典型雨水花园植物进行研究,采用AHP层次分析法对29种雨水花园植物进行综合评价,从3个准则层和9个指标层构建植物评价体系。[结果]指标层中的抗旱性、抗湿性、绿化美化特性、去污降污能力4个指标对于雨水花园植物的选择具有重要影响。千屈菜、红蓼、东方狼尾草、鸢尾、细叶芒、花叶芒6种植物综合评价等级为1级;再力花、常夏石竹、八宝景天、美人蕉、金鸡菊、马鞭草、大丽花7种植物综合评价等级为4级;香彩雀、紫叶狼尾草、蜀葵等16种植物综合评价等级为2—3级。[结论]综合评价值为1级的植物是豫北地区建设雨水花园的首选植物;综合评价等级为4级的植物是雨水花园慎重选择的植物材料;综合评价等级为2—3级的植物,选择合适的区域如蓄水区、缓冲区、边缘区进行雨水花园植物的种植。     

基于韧性理念的城市河流健康评价——以郑州市金水河为例

[目的] 在韧性理念指导下对郑州市金水河健康水平进行评价，为金水河修复与科学管理提供理论依据。 [方法] 以郑州市金水河为例基于压力-状态-响应模型(简称PSR)，构建城市河流健康评价指标体系，采用组合赋权法和物元可拓模型对河流健康水平与发展趋势进行评价与预测。构建城市化-河流健康响应模型，分析城市化对城市河流健康的影响。 [结果] 研究区的河流健康水平呈现明显的空间差异性，河段1，3，6，7，8，11，14的健康等级为健康、亚病态、亚病态、病态、亚健康、亚病态、健康(河段编号从河口向上游依次变大)，其中位于新城区的河段健康水平较老城区高，河段1，3，8，14健康水平有进一步恶化的趋势，而河段6，7，11的健康水平有向好发展的趋势；城市化水平(城市流域不透水面积比，ISC)对于河流健康水平产生显著影响的阈值在50%左右。 [结论] 研究区各河段健康水平在周边城市环境的影响下存在明显的空间差异，城市河流的健康水平与城市化水平密切相关，在对城市河流保护与修复时应加强城市规划的科学性以促进水城共融。     

基于熵权灰色关联法的高寒贫困山区生态脆弱性分析——以青海省海东市为例

[目的]对青海省海东市6个区县的生态脆弱性进行定量研究,为缓解高寒贫困山区贫困状态、提高生态环境保护意识提供参考,为国家深入实施精准扶贫工作提供依据。[方法]选择经济发展状况、社会发展状况和自然生态环境状况3个评价维度构建高寒贫困山区生态脆弱性评价指标体系,运用熵权灰色关联法,对其进行定量分析与评价。[结果]互助县生态脆弱度为0.850 1,属微度脆弱等级,平安区生态脆弱度为0.712 8,属轻度脆弱等级,循化县生态脆弱度为0.557 3,属于中度脆弱等级,乐都、民和及化隆3区县生态脆弱度均小于0.45,属于重度脆弱等级。青海省海东市高寒贫困山区生态脆弱性评价指标的综合关联度从高到低的顺序依次为:互助县平安区循化县化隆县乐都区民和县。[结论]自然生态环境状况和资源禀赋严重制约经济社会发展的同时,对生态脆弱性也有显著的影响。     

河南省植被覆盖度及其景观格局时空变化

[目的]对河南省近10a来植被覆盖度及其景观格局的时空变化及其驱动因素进行分析,为区域经济—社会—环境持续协调发展提供决策参考。[方法]基于2000,2003,2006,2009年MOD13Q1数据集,借助ArcGIS 9.3和Fragstats 3.3软件平台进行定量分析。[结果]10a尺度上,河南省植被覆盖以高覆盖度为主,总体覆盖度呈现先下降后上升的特点,2003年最低,为72.64%;2009年最高,为76.48%;极高植被覆盖度区域主要分布在豫西的林区,最低区域主要分布在城市建成区、大型水库和沿黄河生态涵养带;城市与建成区植被覆盖度呈现波动中下降趋势且其植被覆盖度等级景观格局向恶性方向发展,农田区和自然植被区则与城市建成区变化趋势相反。[结论]降水和气温的变化、快速城镇化以及河南省城镇化、新型工业化、新型农业现代化协调发展战略的实施是导致上述河南省植被覆盖度及其景观格局变化的主要原因。     

Potential of wild species for genetic enhancement of some semi-arid food crops

Discovery and incorporation of genes from wild species provide means to sustain crop improvement, particularly when levels of resistance in the cultigens are low and virulent strains of pests and pathogens overcome the host plant resistance. The extent of utilization and the potential of the wild genepool for genetic enhancement were reviewed in five important food crops viz. sorghum, pearl millet, chickpea, pigeonpea and groundnut grown in the semi-arid tropics. Introgression from compatible wild germplasm in the primary gene pool resulted in transfer of new cytoplasmic male sterility systems in pearl millet and pigeonpea, development of high protein, cleistogamous flower and dwarf pigeonpea lines and foliar disease resistant groundnut cultivars. Utilization of wild species in secondary and tertiary gene pools has been generally limited due to sterility, restricted recombination or cross incompatibility. Nevertheless, these species are extremely important as they contain high levels of resistance to several important biotic and abiotic stresses. Several of them, like those belonging to the Parasorghum section and the rhizomatous Arachis species are sources of multiple resistances and hold great promise to sustain crop productivity.     

“绿色革命”以来大气CO2浓度升高对C3作物营养品质的影响

自20世纪60年代"绿色革命"以来,育种技术和农耕技术的发展促进了农作物产量的大幅提升,然而作物的营养品质出现下降趋势。在相似的遗传背景下,大气CO_2浓度升高会使单位体积农作物产品的营养元素含量下降,因此"绿色革命"至今,农作物产品的营养元素下降可能受大气CO_2浓度升高影响。通过植物生长箱模拟"绿色革命"初期和目前的大气CO_2浓度水平(310μmol/mol和400μmol/mol),针对主要C_3作物水稻、小麦和大豆,研究"绿色革命"以来大气CO_2浓度升高对其籽粒的C、N、Fe、Zn元素含量的影响,结果表明:CO_2浓度升高对3种作物籽粒的C元素含量几乎没有影响,变化幅度在±1.5%之间;籽粒的N、Fe、Zn元素含量普遍呈现下降趋势,但均未达到显著水平。     

Faculty positions:Center for Agricultural Resources Research,Chinese Academy of Sciences

正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications     

低氮和干旱胁迫对富士和秦冠生长及氮素利用的影响

【目的】以富士（Fuji）、 秦冠（Qinguan）嫁接在平邑甜茶（Malus hupehensis Rehd.）上的当年生盆栽苗为试验材料,采用砂培方法,研究了缺氮胁迫和干旱对富士和秦冠生长情况、 光合参数、 植株各部位氮磷钾含量及氮素利用效率的影响,分析比较了低氮干旱条件下富士和秦冠生长及氮素利用的差异,以期为果树生产高效肥水利用提供理论指导。【方法】试验共设四个处理: 正常氮正常水（ZZ）、 低氮正常水（DZ）、 正常氮干旱（ZG）、 低氮干旱（DG）。氮素和水分均设置两个水平,分别为正常氮（6 mmol/L NO-3-N）、 低氮（0.3 mmol/LNO-3-N）、 正常供水（保持盆中砂子相对含水量为饱和含水量的80%~85%）、 干旱处理（保持盆中砂子相对含水量为饱和含水量的60%~65%）。【结果】富士和秦冠的生物量（茎和叶）、 株高茎粗等生长指标以及光合速率、 气孔导度、 蒸腾速率均为正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）,并且相对应处理下秦冠的以上指标均高于富士;正常供水下,缺氮处理使富士、 秦冠的根冠比比正常氮处理均有所增加,富士提高了2.05%,秦冠提高了22.40%。富士和秦冠的氮、 磷、 钾含量均表现出正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）; 氮、 钾元素含量在植株各部位的分布顺序依次是叶＞根＞茎,磷元素则是根＞叶＞茎;光合氮素利用效率（PNUE）和氮素利用效率表现为秦冠处理之间差异极显著,富士处理之间差异不显著;秦冠的PNUE和NUE明显高于富士,在低氮正常水（DZ）处理下,秦冠氮肥利用率比富士高42.07%,在低氮干旱（DG）处理下高64.14%;低氮胁迫下富士和秦冠的NUE显著提高,并且秦冠提高的幅度高于富士。【结论】施用氮肥能够显著提高富士与秦冠的干物质量,同等水肥条件下,秦冠生长优于富士;水分亏缺会减少叶片对氮的吸收,干旱条件下适度增施氮肥,可提高果树的抗旱能力;低氮干旱胁迫下秦冠的生长指标、 光合指标及氮素利用效率指标均优于富士,表现出较强的抗低氮干旱胁迫的能力。     

Collection and preliminary evaluation of native turfgrass accessions in Italy

Despite a raising interest on turfs in Italy, all theavailable varieties of this kind in the Country are of foreign origin, and areoften poorly adapted to the prevailing climatic conditions. This prompted tobegin a collection activity of indigenous turfgrass species, with the ultimategoal of identifying promising materials for future breeding based on localgenetic resources. The collection was carried out in three areas of Italy, viz.the northern Po Plain, the coastal region of Liguria, and the island of Sardiniathat are characterised, respectively, by subcontinental, warm temperate, andtypical Mediterranean climate. Altogether, 141 sites were visited, yielding 226accessions belonging to eight species of potential interest for turfs:Poa pratensis, Poa trivialis,Festuca rubra, Festuca arundinacea,Lolium perenne, Agrostis stolonifera,Agrostis tenuis, and Cynodon dactylon,this last being a warm-season grass. Poa pratensis andCynodon dactylon were mostly collected in northern Italyand Sardinia, respectively, whereas Festuca arundinacea andLolium perenne were rather ubiquitous. The collection sitesranged from 0 to 1040 m asl, but sites over 750 m wereonly visited in the inner part of Sardinia. All the accessions, collected aswhole plants, were transplanted at Lodi, northern Italy, where they are beingevaluated. Their preliminary evaluation for traits of importance for turf use,such as sward colour and overall quality, highlighted the great variation andthe occurrence of interesting accessions in all species. Other characters wererecorded, bearing specific importance in individual species, and in all casespromising accessions were identified. The germplasm of Festucarubra, Festuca arundinacea, and Loliumperenne proved highly infected by endophytic (symbiotic) fungi of thegenus Neotyphodium.     

Pasture Vegetation Elemental Analysis by Laser-Induced Breakdown Spectroscopy

Laser-induced breakdown spectroscopy (LIBS) is a new technique for the analysis of plant material. This study investigates the application of LIBS to pasture-based plant samples. The LIBS measurements were obtained from pelletized pasture samples (100 samples) that had been also analyzed by inductively coupled plasma–optical emission spectroscopy (ICP-OES) following microwave digestion for calibration and comparison purposes. Comparisons for elements sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), boron (B), phosphorus (P), and sulfur (S) showed that LIBS could be used for almost all the standard profile total elements with concentrations down to low mg/kg levels (observed error of Na: 0.024 percent, K: 0.18 percent, Mg: 0.016 percent, Ca: 0.073 percent, P: 0.017 percent, Mn: 31 mg/kg, Fe: 150 mg/kg, Zn: 6.6 mg/kg, and B: 1.1 mg/kg). Elemental analysis at less than mg/kg levels was not possible using LIBS. The elements S and Cu were particularly difficult to analyze with reliability using LIBS at the concentration levels found in the plant samples. Replacing microwave digestion and subsequent ICP analysis with a direct analysis of dried plant samples using LIBS has the potential to improve the productivity and reduce the cost of testing.     

Leaf position and genotype differences for mineral element concentrations in sorghum grown on tropical acid soil 1

Mineral element deficiencies and toxicities are common problems associated with sorghum [Sorghum bicolor (L.) Moench] production on acid soils. To better understand some of the mineral element problems and the analysis of plant tissue of sorghum plants grown on acid soils, four sorghum genotypes were grown on an acid Oxisol at Carimagua, Colombia limed with dolomite at 2 and 6 Mg ha^‐1.

Samples for mineral element analyses were obtained from leaves at different positions on the four genotypes. Concentrations of P and Mg were highest in the flag leaf (Leaf No. 1) and decreased as the position on the plant declined from the top of the plant for plants grown at 2 Mg lime ha^‐1. Similar decreases in P, Mg, K, and Zn concentrations occurred in plants grown with 6 Mg lime ha^‐1. Concentrations of Ca, S, Si, Mn, Fe, Cu, and Al increased as leaf position declined from the flag leaf for plants grown at 2 and 6 Mg lime ha^‐1. The higher lime supply enhanced Ca and reduced Mn and Fe concentrations in leaves. Differences in mineral element concentrations for the four genotypes used were fairly extensive. The elements to show the greatest range among genotypes were Al and Si and the elements to show the least range among genotypes were P, K, and S. Care should be used in collecting leaf samples for plant analysis and genotypic differences for accumulation of mineral elements should be considered in interpretation of results.     

Short-term variation in the concentration of selected ions within individual tropical rainstorms

Rainwater was collected at the campus of the University of Brunei Darussalam in Bandar Seri Begawan, Brunei Darussalam, using a funnel-in-bottle sampler. Polypropylene bottles were changed at intervals during rainstorm events. The pH and conductivity were determined immediately after collection on aliquots of the sample. Samples were refrigerated at 5°C for subsequent chemical analysis. Analyses for Na, Mg, Ca, Zn and Fe were carried out by means of inductively coupled plasma atomic emission spectroscopy (ICP-AES); Cu and Mn were analysed by graphite furnace atomic absorption spectroscopy (GFAAS); K was analysed using flame atomic emission spectroscopy (FAES); and Cl^–, NO₃ ^– and SO₄ ^2– were analysed by ion chromatography (IC). Concentration versus time profiles are reported for three rainstorm events. All ions exhibited a decrease in concentration during the rainstorm. The first sample contained the highest concentration of ions, consistent with a first-flush effect. The contribution of the initial stages of the shower to the total quantity of ion deposited during the entire rainstorm is quite overwhelming; in many cases 20 to 30% of the mass was deposited in less than 5% of rainstorm duration. On the other hand, the pH and conductivity variation during rainstorms did not exhibit a consistent pattern.     

Leaf litter selection by detritivore and geophagous earthworms

Summary Litterbag experiments with 10 different kinds of leaf litter showed that detritivore (Lumbricus species) and geophagous (Aporrectodea species) earthworms prefer certain litter types over others, since different numbers of worms were found below the litter after 50–52 days of exposure in a pasture. The detritivores preferred Fraxinus, Tilia, and predecomposed Ulmus and Fagus litter to Fagus litter and paper, while geophages preferred Tilia litter to Alnus and Ulmus litter, so that the two groups of earthworms showed different preferences. The detritivores seemed to be more selective than the geophages. The palatability of the litter was examined in relation to the C: N ratio, the lignin concentration and the initial and final polyphenol concentration. The numbers of detritivores were significantly correlated with the C: N ratio and the final polyphenol concentration, so that selection of litter seems to be related to palatability. The numbers of geophages were not significantly correlated with any of the parameters for palatability. The disappearance of litter after 50–52 days appeared to be due to detritivore activity, since the numbers found below the litter were positively and significantly correlated with the litter disappearance. There was no significant correlation with geophage activity. This indicates that detritivores use litter as food, and therefore influence the composition of the litter layer.     

The 5S rRNA gene diversity in the genus <Emphasis Type="Italic">Secale</Emphasis> and determination of its closest haplomes

We analyzed 127 rDNA sequences (5S DNA units) obtained from 23 seed accession samples from more or less 10 taxa in wild and cultivated rye, genus Secale L. The sequences fell into two known groups, here assigned to two unit classes, viz. long R1 and short R1 (designations to reflect on R haplome of rye). The different taxa could not be fully differentiated based on the 5S DNA units. We searched for 5S DNA sequences from known unit classes most closely similar to the long R1 and the short R1. One set with the long R1 unit class contained sequences of the long P1 unit class from Agropyron (P haplome) and from Kengyilia (StYP haplome), long J1 from Thinopyrum (J haplome), whereas the set with the short R1 included the long S1 from Pseudoroegneria (St haplome) and Kengyilia (StYP haplome), the short J1 from Thinopyrum (J haplome) and the short V1 from Dasypyrum (V haplome). Each of the two sets was analyzed separately by maximum likelihood (ML) phylogenetic analysis from which we were able to infer that the 5S DNA units of Secale differentiated in a non-clock fashion and followed the HKY substitution model in the gene tree with the long R1 unit class and the HKY + G in the gene tree with the short R1 unit class. A complementary Bayesian analysis yielded identical tree topologies to the ML ones for each of the two sequence sets. In the tree with the long R1 units the long P1 and long J1 unit classes were closest to the long R1 unit class, whereas in the tree with the short R1 units the long S1 and short J1 unit classes were closest to the short R1 unit class, indicating possibly a close relationship between the St, J and R haplomes.