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1.
深圳市基本生态控制线划定对生态系统服务价值的影响 总被引:2,自引:0,他引:2
基于深圳市2002、2005和2010年的土地变更调查数据,分析了基本生态控制线划定前后深圳市土地利用面积变化特征,运用基于单位面积价值当量因子的方法对生态系统服务价值进行评估,并采用倍差法研究了基本生态控制线政策对生态系统服务价值的影响。结果表明:2002—2010年深圳市土地利用总体呈现耕地、园地、草地和水域面积减小,建设用地面积增大,林地面积先减小后增大的趋势;该区生态系统服务价值总体减小,但基本生态控制线划定之后总价值减小的速率降低;各土地利用类型中,林地和水域是构成深圳市生态系统服务价值的主要来源,而各项生态系统服务中,水源涵养产生的价值最大;生态系统服务价值低值范围不断扩大,蚕食价值高的地区,尤其以西部沿海、宝安北部、光明新区、龙华北部以及龙岗南部地区价值降低最为明显;基本生态控制线内生态系统服务价值以中、较高为主,价值变化不明显,线外以低、较低为主,且呈现不断降低的趋势;倍差法结果表明基本生态控制线政策对生态系统服务价值的提高存在促进作用,提升幅度约为1.6%。 相似文献
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重金属对海洋桡足类的影响研究进展 总被引:1,自引:0,他引:1
桡足类是海洋浮游动物种群的主要组成部分和重要的初级消费者,重金属污染对其影响可通过食物链传递到其他海洋生物甚至人类。综述了近20 a来重金属对桡足类影响的研究进展,包括重金属对桡足类的毒性和生理效应,重金属在桡足类体内蓄积及桡足类体内重金属的食物链(网)传递。并指出今后的研究重点:桡足类体内致毒重金属的存在形式,重金属食物暴露对桡足类生理生化影响机理,以及重金属对桡足类生活史的影响。 相似文献
4.
胶州湾浮游桡足类时空分布 总被引:4,自引:1,他引:3
根据2003年1月至12月在胶州湾所获得的浮游生物样品,已鉴定浮游桡足类28种,幼虫、幼体6类.分析了该海区浮游桡足类的分布﹑时空变化及其与生态环境因子的关系,同相关历史资料进行了比较,结果表明,浮游桡足类的种类组成单纯,生态属性以暖温带、近岸低盐种类为主.浮游桡足类的丰度分布具明显的月份变化,高峰在7月份,为181.61个/m3,最低在12月份,为23.53个/m3,全年平均为71.42个/m3.浮游桡足类丰度的平面分布不均匀,最大丰度在5号站,为132.62个/m3,最小丰度在8号站,为40.45个/m3,丰度平面分布的变化趋势基本是湾北部海域大于湾南部海域.浮游桡足类丰度的时空分布,主要种类的季节更替,近20a来的变化趋势基本相同,高峰出现时间的差异,是受温度年季变化差异因素的影响.浮游桡足类丰度的时空分布与海水温度和盐度密切相关,与温度的关系更重要于与盐度的关系.并且用胶州湾的调察资料证实了浮游桡足类对浮游植物的依存关系,浮游植物为浮游桡足类的生长、繁衍提供了饵料. 相似文献
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南海北部浮游桡足类对浮游植物的摄食压力 总被引:1,自引:0,他引:1
于2004年2月(冬季)和8月(夏季)在南海北部使用肠道色素法研究了浮游桡足类群落对浮游植物现存量的摄食压力。将底到表垂直拖网(网孔径200μm)获得的桡足类分为中型(>500μm)和小型(200~500μm)两个体长组。冬季:中型桡足类的丰度为103~2343(平均633)ind/m3,肠道色素为0.15~2.71(平均1.31)ng/ind,肠道排空率为0.011(A4)~0.019(C1)min-1,个体摄食率为3.13~58.48(平均28.36)ng/(ind.d),群落摄食率为1902~62369(平均18679)ng/(d.m3),对浮游植物生物量的摄食压力为每天0.25%~6.39%(平均3.04%)。小型桡足类的丰度为418~6250(平均1691)ind/m3,肠道色素为0.18~3.44(平均1.19)ng/ind,肠道排空率为0.012(A4)~0.016(C1)min-1,个体摄食率为3.67~70.04(平均24.34)ng/(ind.d),群落摄食率为1540~158561(平均44227)ng/(d.m3),对浮游植物生物量的摄食压力为每天0.44%~15.70%(平均6.59%)。浮游桡足类群体对浮游植物生物量的摄食压力为每天1.02%~20.10%(平均9.63%)。夏季:中型桡足类的丰度为111~1298(平均621)ind/m3,肠道色素分别为0.22~1.58(平均1.03)ng/ind,肠道排空率为0.017min-1,个体摄食率为5.52~39.92(平均25.95)ng/(ind.d),群落摄食率为4411~26667(平均12878)ng/(d.m3),对浮游植物生物量的摄食压力为每天0.23%~6.52%(平均2.52%)。小型桡足类的丰度为756~8804(平均2990)ind/m3,肠道色素含量为0.09~2.92(平均0.87)ng/ind,肠道排空率为0.020min-1,个体摄食率为2.73~87.77(平均26.26)ng/(ind.d),群落摄食率为9309~139817(平均47191)ng/(d.m3),对浮游植物生物量的摄食压力为0.86%~37.79%(平均10.99%)。浮游桡足类群体对浮游植物生物量的摄食压力为1.09%~39.95%(平均13.51%)。数据表明,2月份和8月份桡足类群体对浮游植物现存量的摄食压力较低,桡足类摄食不是南海北部浮游植物死亡的主要原因。 相似文献
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海水实验围隔中桡足类对海洋原甲藻摄食的研究 总被引:7,自引:0,他引:7
现场研究了发生严重海洋原甲藻(Prorocentrummicans)水华后海水实验围隔中桡足类火腿许水蚤(Schmackeriapoplesia)和长腹剑水蚤(Oithonasp.)的摄食强度.结果表明,体长在125mm以上的火腿许水蚤成体及其部分桡足幼体对海洋原甲藻的摄食率平均为12140cels·ind-1·d-1;体长不到125mm的部分火腿许水蚤桡足幼体和长腹剑水蚤成体及其桡足幼体的摄食率仅为1133cels·ind-1·d-1.实验期间围隔中海洋原甲藻的浓度为850~16170cels·ml-1,该藻的种群增长率为-0.002~0.150.当海洋原甲藻细胞处于生长期时,桡足类的摄食不足以抑制该藻种群的增长,因此围隔中桡足类不可能阻止海洋原甲藻水华发生或使水华发生后迅速消退 相似文献
7.
两种桡足类短期热冲击的高起始致死温度值 总被引:1,自引:0,他引:1
于2007年4月研究了亚热带海域近海种桡足类中华哲水蚤(Calanus sinicus Brodsky)和真刺唇角水蚤(Labidocera euchaeta Giesbrecht)在不同驯化温度下热冲击15、30、45 min后的24 h高起始致死温度(upper incipient lethal temperature,24-h UILT50).结果表明:(1)在相同驯化温度下,两种桡足类短期热冲击24-h UILT50随暴露时间的延长而降低;(2)在相同暴露时间下,两种桡足类短期热冲击24-h UILT50随驯化温度的上升均有不同程度的上升,但这种升高的趋势会随驯化温度的上升而变缓,且趋于一固定值后不再上升;(3)中华哲水蚤在暴露时间为15、30、45 min的24 h最高起始致死温度(ultimate upper incipient lethal temperature,24-h UUILT50)分别为31.7、31.0、30.3℃,真刺唇角水蚤在暴露15、30、45 min时的24-h UUILT50分别为36.5、36.0、35.4℃;(4)在相同驯化温度和暴露时间条件下,真刺唇角水蚤对短期热冲击的耐受性显著强于中华哲水蚤. 相似文献
8.
武汉东湖桡足类的生态学演变 总被引:13,自引:2,他引:13
根据1962-1963,1974-1975,1979-1991年在武汉东湖进行的调查资料,考察了过去三十年内在东湖两个代表性采样站桡足类的种类组成及现存量的变化。结果表明:桡足类种类数由60年代的14种减少为90年代的7种,I、Ⅱ站在种类组成的差别趋于消失。统计结果表明,东湖桡足类现存量以80年代初、中期较高。但在水平分布格局上却发生了根本变化,由1987年前的I站现存量高于Ⅱ站,至1987年后Ⅱ站高于I站。本文还就影响东湖桡足类演变的生态因子进行了讨论。 相似文献
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珠江口浮游桡足类的生态研究 总被引:7,自引:0,他引:7
根据2002~2003年珠江口12个航次的调查资料,分析了浮游桡足类种类组成、优势种演替和丰度的时空变化,探讨其影响因素。以表层盐度(S)变化将调查海域划分三个区域:I区(S<25)、Ⅱ区(2530)。结果表明:调查海域共出现桡足类65种,Ⅱ区和Ⅲ区的种类多于I区;桡足类的平均丰度为118ind·m-3,三个区域之间的比较为Ⅱ区(165ind·m-3)>I区(129ind·m-3)>Ⅲ区(62ind·m-3),春、夏季的丰度高于冬季;优势种有明显的时间和区域上的变化。I区9个航次的研究结果表明:I区桡足类种类较少;各月份之间的平均丰度差别大,由河口内往外呈增加趋势。盐度是影响珠江口桡足类种类组成和数量变化的主要因素。 相似文献
11.
The biological oceanography of waters adjacent to Australia's North West Cape (21° 49 S, 114° 14 E) was studied during the austral summers of 1997/98 and 1998/99. We measured egg production rate (EPR) by the small paracalanid copepods that dominated the calanoid community. Bottle incubation experiments were conducted at a shallow (20 m) station in the mouth of Exmouth Gulf, and at a shelf-break station (80 m). In 1997/98, we measured EPR by Paracalanus aculeatus, P. indicus, Acrocalanus gracilis and Bestiolina similis, but in 1998/99, we concentrated on P. indicus. Maximal observed EPRs by Paracalanus and Acrocalanus species were 30 eggs female–1 d–1, but B. similis attained only 17 eggs female–1 d–1. Sporadic measurements of EPR by P. aculeatus minor (maximum 4 eggs female–1 d–1) and Parvocalanus crassirostris ( 9 eggs female–1 d–1) were also made. However, maximal EPRs were seldom achieved and were often less than 10 eggs female–1 d–1. There was no difference between EPR of either P. indicus or B. similis in 1997/98 and 1998/99, despite differences in temperature. Trophic resources severely limit copepod egg production in this area. We suggest that variability and skewness of egg production data derived from individual incubations may be used to judge the degree of food limitation of the population and the variability in feeding success between individuals. The dominance of small copepods and the invariance in their EPR suggest that pulses in physical forcing and subsequent primary production will be severely damped by trophodynamic processes before reaching larval fish. 相似文献
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The ocean is undergoing warming and acidification. Thermal tolerance is affected both by evolutionary adaptation and developmental plasticity. Yet, thermal tolerance in animals adapted to simultaneous warming and acidification is unknown. We experimentally evolved the ubiquitous copepod Acartia tonsa to future combined ocean warming and acidification conditions (OWA approx. 22°C, 2000 µatm CO2) and then compared its thermal tolerance relative to ambient conditions (AM approx. 18°C, 400 µatm CO2). The OWA and AM treatments were reciprocally transplanted after 65 generations to assess effects of developmental conditions on thermal tolerance and potential costs of adaptation. Treatments transplanted from OWA to AM conditions were assessed at the F1 and F9 generations following transplant. Adaptation to warming and acidification, paradoxically, reduces both thermal tolerance and phenotypic plasticity. These costs of adaptation to combined warming and acidification may limit future population resilience. 相似文献
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Upper lethal temperature tolerance was determined for 26–81 mm, age 0 black crappie Pomoxis nigromaculatus of three size classes using both a rapid transfer and slow heating protocol. Rapid transfer protocols determined 24 LT50 values of 33–8, 35–1 and 31–5° C for size classes with mean total lengths of 30–2, 45–6 and 74–9 mm. A predictive model was generated from the slow heating protocols that relates lethal temperature to acclimation temperature, total length, and condition factor (K) as predictors. 相似文献
14.
CLIFFORD RAY JOHNSON 《Zoological Journal of the Linnean Society》1978,64(1):59-62
Macrocyclops albidus were exposed for 24 hours to ABATE®, fenthion, malathion, methyl parathion, and chlorpyrifos at concentrations of 1, 5, 10, 25, and 50 parts per billion (ppb). Exposure to chlorpyrifos resulted in the greatest mortality to M. albidus; concentrations of 25 and 50 ppb caused 100% mortality. The thermal tolerance was lowered significantly by all chemicals at concentrations from 1 to 50 ppb. 相似文献
15.
Plankton and littoral samples were obtained from several ponds and lagoons of different environments in the Mexican state of Tabasco. These systems are located in the Grijalva-Villahermosa or the Usumacinta basins. Twenty-two copepod species were recorded, most of them cyclopoids with neotropical and Caribbean affinities. Physical and chemical data associated with the species, as well as morphometric parameters of the surveyed systems were measured and analyzed. A correlation was found between diversity and parameters related to the productivity and the shoreline development (D
L) of the systems; therefore the littoral heterogeneity could be used to predict the species number in shallow tropical systems. At a regional level, the Tabasco copepod fauna is similar to that known from the Yucatan Peninsula, but different from the faunal associations of central Mexico. Distributional patterns differed slightly between both basins and appear to be correlated with climatic variations. This first survey of the freshwater copepod fauna in the state of Tabasco shows it to be constituted mainly by neotropical forms. 相似文献
16.
Jianliang Yao Junzeng Xue Dengyuan Wang Qinghua Cai Xiangfei Huang Jiankang Liu 《生物学前沿》2008,3(4):525-529
The ecosystem of the Three Gorges in the Yangtze River was changed into an artificial lake (res-ervoir) ecosystem after impoundment in June 2003. We surveyed the seasonal variation and spatial distribution of copepods from April 2004 to January 2005 in order to provide data for clarifying the successional pattern of the ecosystem. From Jiangjin to Maoping, eight copepod species were collected and classified into Calanoida (2), Harpacticoida (1), and Cyclopoida (5). Among them, Mesocyclops pehpeiensis, M. leuckarti and Sinocalanus dorrii had a relatively wide distribution. No distinct dif-ference in species number was found among the sampling sites, but the species composition was different. Species composition, distribution and density of copepods showed significant seasonal variations. In addition, cope-pod density showed an obvious gradient with the distance from the reservoir dam: the nearer to the dam, the denser the copepods. 相似文献
17.
Jianliang Yao Junzeng Xue Dengyuan Wang Qinghua Cai Xiangfei Huang Jiankang Liu 《Frontiers of Biology in China》2008,3(4):525-529
The ecosystem of the Three Gorges in the Yangtze River was changed into an artificial lake (reservoir) ecosystem after impoundment
in June 2003. We surveyed the seasonal variation and spatial distribution of copepods from April 2004 to January 2005 in order
to provide data for clarifying the successional pattern of the ecosystem. From Jiangjin to Maoping, eight copepod species
were collected and classified into Calanoida (2), Harpacticoida (1), and Cyclopoida (5). Among them, Mesocyclops pehpeiensis, M. leuckarti and Sinocalanus dorrii had a relatively wide distribution. No distinct difference in species number was found among the sampling sites, but the
species composition was different. Species composition, distribution and density of copepods showed significant seasonal variations.
In addition, copepod density showed an obvious gradient with the distance from the reservoir dam: the nearer to the dam, the
denser the copepods.
__________
Translated from Biodiversity Science Sinica, 2007, 15(3): 300–305 [译自: 生物多样性] 相似文献
18.
三峡水库初次蓄水后干流库区桡足类的纵向分布与季节变化 总被引:1,自引:0,他引:1
作为大型水利工程, 三峡水库于2003年6月开始蓄水, 蓄水后库区水环境发生了变化。为了了解三峡水库水生态系统的演替规律, 同时为环境保护、渔业资源开发利用以及水环境管理提供理论基础, 我们对三峡水库第一阶段蓄水后桡足类的季节变化和空间分布进行了周年季节性研究。在三峡库区江津至茅坪的10个断面共采集到8种桡足类, 其中哲水蚤目2种、猛水蚤目1种、剑水蚤目5种, 北碚中剑水蚤(Mesocyclops pehpeiensis)、广布中剑水蚤(M. leuckarti)和汤匙华哲水蚤(Sinocalanus dorrii)分布较广。各样点种类数差异不大, 但组成上却有不同。桡足类种类组成、空间分布和密度具有明显的季节变化特征, 此外密度在水库的纵轴上也表现出明显的梯度分布, 越近大坝密度越高。 相似文献
19.
Andrés N. Molina José M. Pulgar Enrico L. Rezende Mauricio J. Carter 《Global Change Biology》2023,29(1):179-188
Global warming is affecting the Antarctic continent in complex ways. Because Antarctic organisms are specialized to living in the cold, they are vulnerable to increasing temperatures, although quantitative analyses of this issue are currently lacking. Here we compiled a total of 184 estimates of heat tolerance belonging to 39 marine species and quantified how survival is affected concomitantly by the intensity and duration of thermal stress. Species exhibit thermal limits displaced toward colder temperatures, with contrasting strategies between arthropods and fish that exhibit low tolerance to acute heat challenges, and brachiopods, echinoderms, and molluscs that tend to be more sensitive to chronic exposure. These differences might be associated with mobility. A dynamic mortality model suggests that Antarctic organisms already encounter temperatures that might be physiologically stressful and indicate that these ecological communities are indeed vulnerable to ongoing rising temperatures. 相似文献
20.
小菜蛾是世界范围内十字花科蔬菜上的重要害虫.临界高温(critical thermal maxi-mum,CTMax)是昆虫耐热性的常用指标.采用动态加热方法,利用自行组装的装置测定了小菜蛾的临界高温,以此作为其耐热性指标,研究发育阶段、饲养温度、世代、性别和热激对小菜蛾耐热性的影响.结果表明:25℃下饲养的小菜蛾4龄幼虫的CTMax均值为50.31℃,显著高于1龄幼虫(43.03℃)、2龄幼虫(46.39℃)、3龄幼虫(49.67℃)以及雌性成虫(45.76℃)和雄性成虫(47.73℃);不同饲养温度(20、25和30℃)下成虫耐热性无显著差异;30℃下饲养1代、3代及6代的不同世代成虫CTMax也无显著变化;所有处理雌雄成虫的CTMax无显著差异;40℃下45 min热激可使5日龄雄成虫的CTMax值从45.51℃增加到46.49℃. 相似文献