安阳市地表水环境质量变化趋势分析及治理对策研究

利用平均综合污染指数和秩相关系数法,对“十二五”至“十三五”期间安阳市地表水环境质量状况进行了综合分析。结果表明：“十二五”至“十三五”期间,安阳市河流各污染因子下降趋势的显著性顺序为：氨氮>总磷>化学需氧量>高锰酸盐指数>生化需氧量,除生化需氧量外,均呈现显著下降趋势;近10年来,安阳市河流Ⅰ～Ⅲ类断面比例呈显著上升趋势,劣Ⅴ类断面比例呈显著下降趋势,“十三五”期间,河流断面水质Ⅰ～Ⅲ类占比增加43.5%,劣Ⅴ类占比下降47.8%,5年间劣Ⅴ类水体呈显著下降趋势,尤其是2020年劣Ⅴ类断面消除,整体水环境质量显著好转,但安阳市地表水污染属于典型的有机型污染。分析了安阳市水环境污染与治理现状,提出了相应的治理对策,为解决安阳市水环境问题提供有力支撑。     

南平市黄脊竹蝗空间分布和发生趋势

为研究南平市黄脊竹蝗空间分布和发生趋势,选取南平市2001—2021年黄脊竹蝗发生面积作为试验数据,采用方差分析、Man-kendall趋势检验和突变分析法进行分析。研究表明:南平市黄脊竹蝗发生的空间分布不均匀,主要分布在南平市的南部和北部,占总面积的89.8%。南平市黄脊竹蝗年均发生面积约1674 hm^(2),总体呈下降趋势,但不显著;延平区、武夷山市和顺昌县发生趋势下降不显著,建阳区和建瓯市发生趋势下降显著,邵武市发生趋势上升不显著,浦城县和松溪县发生趋势上升显著。黄脊竹蝗发生趋势在2007—2008年发生突变,突变前黄脊竹蝗发生总体呈下降趋势,但不显著;突变后黄脊竹蝗发生呈持续下降趋势,2008—2010年下降趋势不显著,2011—2021年呈显著下降趋势。     

新丰江水库水质评价与影响因子分析

根据2020-2022年新丰江水库3个断面监测资料,进行水质评价,利用SPSS20.0分析水位与各化学指标的相关性,并对化学指标做主成分分析,APCS-MLR模型对水库水质的影响因子贡献率进行了分析,结果表明：新丰江水库除总氮外,其余指标均达到《地表水环境质量标准》(GB3838-2002)I类水质标准,水质优良;水库营养状态指数(EI)为30～40,为中营养状态;水库水位与高锰酸盐指数、总磷2个指标呈显著的正相关,与电导率、透明度2个指标呈显著的负相关;水库水质影响因子贡献率呈硝化作用>土壤因子>大气降水>河流补给>未知源的趋势。     

近26年大明湖水质变化趋势及富营养化特征

基于1996～2021年大明湖长时间序列的水质监测数据,选取pH值、溶解氧、氨氮、总磷、总氮、高锰酸盐指数、化学需氧量、生化需氧量等8项指标,通过单因子污染指数法、改进的内梅罗指数法及综合营养状态指数法,分析了大明湖水质的变化趋势、富营养化特征。结果表明：1996～2021年,pH值保持稳定,溶解氧、总氮波动变化,其余指标浓度呈现先下降后保持稳定的趋势;近年来营养水平大致为轻度富营养化状态,还需加大水体富营养化治理力度。     

烟台大沽夹河高锰酸盐指数调查分析

为调查烟台大沽夹河高锰酸盐指数超标原因,提出对策,分析成效。根据新夹河大桥国控水站2021年10月21～26日高锰酸盐指数监测数据、10月24～25日叶绿素a含量测定结果,结合新夹河大桥国控水站上游及周边开展现场勘查情况,分析了高锰酸盐指数超标原因。结果表明：大沽夹河高锰酸盐指数呈8:00～16:00逐渐升高,16:00至次日8:00逐渐降低趋势,pH值偏向碱性,氨氮、总磷、总氮含量呈相对稳定趋势;4个点位水样中叶绿素a含量均处于较高水平。针对引起高锰酸盐指数升高的原因包括秋冬季水生植物大量干枯腐败和藻类植物大量生长,提出了采取综合措施有助于降低高锰酸盐指数,为改善河流水质提供一定依据。     

大清河流域径流变化趋势分析

采用1956—2016年长系列径流资料,选取大清河流域北支水系、南支水系及大清河下游的水文站、典型断面为研究对象,进行Mann-Kendall趋势检验,分析大清河年径流量的变化趋势。结果显示,白洋淀流域近54年的年降雨M-K统计值为-1.492,呈弱减少趋势。对规划实施前后各水文站年均径流量变化分析结果,海河流域综合规划(1993年)的实施对大清河中下游断面年径流量影响较大。     

紫花槭秋季叶片呈色生理变化研究

为了探寻影响紫花槭叶色变化的主要因素,从而为其园林配置提供理论依据,对紫花槭秋季叶片转色不同时期的叶色参数、色素含量、相关酶活性、碳水化合物和矿质元素含量进行了测定。结果表明:1)紫花槭叶色参数L值先上升后降低,a值呈持续上升趋势,b值呈先上升后下降再上升的趋势;2)紫花槭叶片叶绿素含量呈下降趋势,类胡萝卜素含量呈先下降后上升再下降的趋势,花色素苷含量呈上升趋势;3)苯丙氨酸解氨酶(PAL)、查尔酮异构酶(CHI)、查尔酮还原酶(CHR)活性均呈先升高后降低的趋势;4)碳水化合物中蔗糖含量呈先下降后上升再下降的趋势;5)矿质元素中氮、钾含量的变化趋势相同,均呈下降趋势,磷含量呈先上升后下降的双峰趋势,镁含量呈先上升后下降的趋势,钙含量呈先下降后上升再下降的趋势。对不同色素与其他生理指标的相关性分析结果表明:叶绿素含量与氮、钾均存在极显著的正相关关系,与钙存在显著的正相关关系;类胡萝卜素含量与其他指标的相关性均未达到显著水平;花色素苷的含量与PAL、CHI酶活性和氮、钾含量间均呈极显著负相关,与CHR酶活性及钙、镁含量间均呈显著负相关,而与淀粉、蔗糖含量间均存在正相关,但不显著;色素与磷含量无明显的相关性。     

蓬溪县主要地表水体水质现状及水质改善对策

利用2017～2019年遂宁市蓬溪县芝溪河支流田家坝、涪山坝断面及荷叶溪铧头嘴断面水质监测数据,研究了蓬溪县地表水水质现状及其变化趋势,采用主成分分析法确定了主要污染因子。结果表明:蓬溪县境内的水质状况较差,支流断面水质等级为Ⅲ～Ⅴ类,但随时间的增长水质呈显著改善的状态;芝溪河的田家坝断面和涪山断面水质监测指标和荷叶溪铧头嘴断面的季节变化趋势基本一致,芝溪河的水质污染因子为高锰酸盐指数和总磷,荷叶溪铧头嘴断面的水质达标。针对出现的水质问题,提出了蓬溪县境内主要地表水的保护措施,为蓬溪县水资源保护提供科学依据。     

永定河流域土地利用景观格局变化研究

以永定河流域为研究对象,对1978～2009年间6期遥感图像的土地利用情况进行解译,运用景观格局指标,分析永定河流域景观格局动态变化．结果表明：32年来永定河流域以农、林、草业景观为主,耕地面积有下降趋势,林地面积2000年最低,后缓慢上升,水域面积近10年下降明显．景观破碎化程度呈不断上升的趋势,多样性指数逐步升高,景观类型均匀度总体有下降趋势,景观类型转移概率矩阵表明,林地最为稳定,干旱河道的变化最大．     

1961—2021年广西沿海地区极端冷暖事件时空变化

为给红树林保护修复和气象保障服务提供科学依据，基于1961—2021年大气环流指数以及北海、防城港和钦州10个国家站逐日最高、最低气温，采用RClimDex模型计算极端气温指数，采用线性趋势分析、MK突变检验和偏相关分析，研究广西沿海地区极端冷暖事件时空变化规律。结果表明，1961—2021年，霜冻日数、持续冷期指数、冷夜日数、冷昼日数和气温日较差显著下降，热带夜数、夏季日数、持续暖期指数、暖夜日数、暖昼日数、日最高气温的最大值、日最低气温的最大值和日最低气温的最小值显著上升，说明广西红树林生态区冷、暖指数都趋于变暖，与全球变暖趋势正响应，且夜间气温的上升幅度大于白天，昼夜温差变小。冷指数突变年为1988—2015年，暖指数突变年为1996—2012年，冷、暖指数突变时间段相差不大。冷夜日数、冷昼日数、暖夜日数、暖昼日数和持续暖期指数空间分布规律一致，都是除防城港市东南部偏低外，其他地方普遍高；其中暖夜日数、暖昼日数和持续暖期指数在北海市北部地区增加趋势较明显，说明冷、暖指数在研究区的空间差异不大，在北海市北部地区变暖现象较明显。西太平洋副热带高压和欧亚纬向环流增强有利于极端气温上升。     

中亚热带钱江流域天然次生林集水区溪流与降水水质比较

对浙江钱江源生态站大气降水和天然次生林生态系统的径流水质指标进行逐月取样测试和对比分析.结果表明:天然次生林集水区水体中溶解氧含量年平均值达到8.10 mg·L-1,是大气降水的1.12倍;总氮含量年平均值达7.68 mg·L-1,是大气降水的4.49倍.大气降水的生化需氧量年平均值达2.10 mg·L-1,是天然次生...     

高原湖泊型湿地生态系统服务价值评估研究

通过将云南玉溪抚仙湖国家湿地公园生态系统服务价值分为供给服务价值、生态调节服务价值、精神文化服务价值3个一级指标,食物生产（A1）、淡水资源（A2）等8个二级指标进行评估体系构建并计算其生态系统服务价值。结果显示：云南玉溪抚仙湖国家湿地公园生态系统服务价值总量为4.17×10^{9997相似文献}   

Simulation of soil water dynamics in a Caragana intermedia woodland in Huangfuchuan watershed

As vegetation coverage increases, soil water content can decrease due to water uptake and evapotranspiration. At a very high level of plant density, poor growth and even mortality can occur due to the decrease of soil water content. Hence, a better understanding of the relationship between soil water content and the density of plants is important to design effective restoration projects. To study these relationships, we developed a soil water dynamic simulation model of a Caragana intermedia woodland under different slope gradient and slope aspect conditions in the Huangfuchuan watershed on the basis of the previous studies and field experiments. The model took into account the major processes that address the relationships of plants and the environment, including soil characteristics, precipitation, infiltration, vegetation transpiration, and soil evaporation. Daily changes in soil water content, transpiration, and evaporation of the Caragana intermedia woodland with different vegetation coverage, slope gradient, and slope aspect were simulated from 1971 to 2000. Based on the model simulations, we determined the functional relationships among soil water content, plant coverage and slope as well as the optimal plant density on flat slopes. We also determined the effects of slope gradient and slope aspect on soil water content. When slope gradient was less than 10°, the optimal plant density was sensitive to slope gradient. In the slope range from 10° to 30°, plant density was not sensitive to slope gradient. Therefore, it is important to consider planting densities on the hillsides with slope gradients less than 10° for reconstructing vegetation. __________ Translated from Acta Phytoecologica Sinica, 2005, 29(6): 910–917 [译自: 植物生态学报]     

哈尼梯田核心区水文要素变化特征分析

选用元阳县新街镇1958~1996年的降雨量和蒸发量数据资料,收集哈尼梯田核心区主要河流的产水模数,运用距平分析等方法对梯田核心区水文要素进行分析计算.结果表明,元阳梯田核心区降雨、蒸发年内分配不均匀,年际变化趋势不显著.降雨主要集中在5~10月,占全年降水量的76.50%以上,蒸发量主要集中在3~8月,占全年蒸发量的62.96%以上,计算得出干旱指数为0.768 9,产水模数为63.94万m3/km2.     

Impact of stand density on water status and leaf gas exchange in Quercus ilex

Tree thinning reduces tree-to-tree competition and likely contributes to the improvement of tree water status and productivity in water-limited systems. In this study, we examined the importance of competition for water among Quercus ilex trees in open woodlands by comparing the water consumption and physiological status of trees located along stand density gradients which ranged from 10% (low density; LD) to 100% (high density; HD) of canopy cover. The study was carried out at two sites which differed in mean annual rainfall (506 and 816 L m⁻²; D_site and W_site, respectively). Predawn and midday leaf water potential (ψ_d and ψ_m, respectively) and CO₂ assimilation rate (A) were measured every two weeks from mid May to mid September, in eight trees located along a stand density gradient at each site. Sap flow and soil moisture were measured only at D_site. Sap flow was continuously recorded by sap flowmeters (constant heating method) installed in 12 trees along two stand density gradients. Soil moisture (?) was measured every 20 cm for the first meter and then every 50 cm up to 250 cm. Measurements were conducted in 18 soil profiles, 6 located in HD and 12 in LD (six beneath and six out the canopy). At W_site, differences among stand densities for ψ and A were very small and emerged only at the end of the dry season. At D_site, ψ (both predawn and midday), A, ?, and sap flow density were significantly higher in LD trees than in HD ones. At D_site, some water remained unused in the soil at the end of the dry season beyond the canopy in the LD areas, and trees did not experienced such an acute water deficit (ψ_d > −1 MPa) as the HD trees did (ψ_d < −3 MPa). Summer tree transpiration at the stand level (E_stand) tended to saturate with the increase of canopy cover. E_stand increases by 32% when canopy cover goes from 50% to 100%. Results confirmed that the increase of tree-to-tree competition with stand density was much more significant at dry sites. In these sites, tree thinning is recommended as a way to maintain tree functioning.     

云南省玉溪市抚仙湖湿地公园规划设计探讨

近年来旅游人数的持续增长,对云南玉溪抚仙湖的生态承栽力提出了严峻的挑战,其生物多样性以及水体质量都受到了一定程度的破坏。根据生态系统的空间关系以及格局与过程的关联性和景观规划的实用性这两个方面,参照《城市湿地公园规划设计导则》,并结合提出的规划原则对玉溪抚仙湖湿地公园进行了规划设计,形成了一个以“生态性、独创性、休闲性、经济性”为基本定位的,满足人们荡涤身心、陶冶情操等需求的多功能生态型娱乐场所。     

Application of the drilling resistance method for annual ring characteristics: evaluation of Taiwania (<Emphasis Type="Italic">Taiwania cryptomerioides</Emphasis>) trees grown with different thinning and pruning treatments

 The effects of various thinning and pruning methods on the density profile and annual ring characteristics of Taiwania (Taiwania cryptomerioides Hay.) using the drilling resistance technique were investigated. The results showed that thinning caused wider annual rings than medium thinning or no thinning, and pruning caused narrower annual rings than no pruning. Moreover, the thinning treatment affected annual rings more effectively than the pruning treatment. The average ring density after the thinning treatments showed a trend as follows: no thinning > medium > heavy. This indicates that thinning reduces the average ring density. The average ring density after the pruning treatments showed a trend as follows: medium > no pruning > heavy. However, the differences between thinning and no thinning were not statistically significant. The percentage of latewood in Taiwania after these three thinning and pruning treatments are shown. The results with silvicultural treatments have the order: medium > not treated > heavy, but there are no statistically significant differences among thinning, pruning, and thinning where pruning interactions were observed. Moreover, there were highly significant negative relations between the average ring width and the various ring densities for Taiwania, but the determination coefficients were small. In addition, there was a highly positively significant relation between the latewood percentage and latewood width. Received: November 22, 2001 / Accepted: May 21, 2002 Acknowledgments The authors thank the National Science Council of ROC for financial support through grant NSC-90-2313-B-002-338, and the Taiwan Forestry Research Institute for their contribution (210). Correspondence to:C.-J. Lin     

Adaptation of herbaceous plant species in the understorey of <Emphasis Type="Italic">Pinus brutia</Emphasis>

Most of Pinus brutia (Ten.) Holmboe forests are grazed, as silvopastoralism is well adapted in the Mediterranean environment. However, little attention has been paid to the demographic dynamic of the understorey vegetation even though it is strongly affected by the absorbed radiation. The purpose of this study was to examine the adaptation of herbaceous plant species under a Pinus brutia canopy, in Northern Greece. Monocultures of four plant groups (annual and perennial grasses, annual and perennial legumes) were sown in experimental areas of 50%, 70% and 100% light intensity. The density of annual and perennial grasses and perennial legumes were decreased by the shade cast by the Pinus brutia canopy. Population density of the annual legumes was little affected by light intensity: the annual grasses Bromus mollis L. and Lolium rigidum Gaudin; the perennial grasses Dactylis glomerata L. var. palestine, Festuca arundinacea and Agropyron cristatum (L.) Gaertn; the perennial legume Medicago sativa L. var. romana; the annual legumes Medicago lupulina L. and all the tested varieties of Trifolium subterraneum adapted well to the 50% light intensity habitat.     

Na2SO4胁迫对沙枣幼苗生长和光合生理的影响

采用盆栽控制试验,研究了不同浓度(0、60、120和180 mmol·L-1)Na2SO4胁迫对沙枣幼苗生长和光合特性的影响。结果表明:(1)盐胁迫对沙枣幼苗生长具有显著的抑制效应。不同浓度Na2SO4胁迫沙枣的株高、侧枝数、总叶面积、单株叶片数、比叶面积以及各组织(除根)生物量均显著低于对照,且均随盐胁迫浓度的升高呈下降趋势,而根冠比值则由对照的0.153 1显著增加到180 mmol·L-1Na2SO4胁迫幼苗的0.348 7。(2)盐胁迫显著降低了沙枣幼苗的光合能力。随着Na2SO4胁迫的加剧,净光合速率(Pn)、气孔导度(Gs)、胞间CO2浓度(Ci)和蒸腾速率(Tr)均呈下降的趋势,而气孔限制值(Ls)和水分利用效率(WUE)则依次增加,且Pn下降主要受气孔限制;180 mmol·L-1Na2SO4胁迫沙枣幼苗的Pn、Gs、Ci和Tr分别为对照的71.57%、30.85%、67.15%和51.65%,而Ls和WUE则分别为对照的1.91、1.38倍。(3)盐胁迫强度与幼苗株高、总叶面积、单株叶片数、比叶面积、茎生物量、叶生物量、总生物量等生长指标以及Pn、Gs、Ci、Tr等光合参数呈极显著负相关,叶片的光合参数与总叶面积、单株叶片数呈显著或极显著正相关,而叶片的生长指标、光合参数与幼苗的株高生长和生物量累积也呈显著或极显著正相关。     

三江源湿地变化驱动因子定量研究

利用1990、1997、2007年3期TM遥感影像数据,2008年调查的652块地面样地数据,1990-2007年各年气象和社会经济数据以及地形图、湿地分布图、植被分布图数据,通过偏相关分析,确定各类湿地变化的主导驱动因子,建立湿地变化驱动模型.结果表明:河流和河滩湿地变化的主要驱动因子是年均温度、年蒸发量、年均相对湿度和年奶产量;湖泊湿地变化的主要驱动因子是年蒸发量、年均相对湿度、年人口数量和年奶产量;沼泽和全部湿地变化的主要驱动因子是年降水量、年人口数量和年人均收入.驱动模型的判定系数校正值R2分别为0.830 1、0.757 2、0.967 5、0.833 3、0.967 9,经F检验,在95％可靠性水平下整个模型的自变量对随机变量的影响是显著的.