Long-term changes in zooplankton and the climate of the North Atlantic   总被引：13，自引：3，他引：10  

Planque  Benjamin; Taylor  Arnold H. 《ICES Journal of Marine Science》1998,55(4):644-654

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Response of macroinvertebrate communities to thermal regime in small Mediterranean streams (southern South America): Implications of global warming     

《Limnologica》2020

The seasonal nature of the stream thermal regime has been recognized as an important factor for the structure of benthic macroinvertebrate communities. In this study, we show the importance of temperature and the potential implications of global warming on the composition of benthic macroinvertebrate communities in Andean watersheds. Here we show that thermal factors (mean temperature and monthly range) partially explain the seasonal variability of macroinvertebrates in Andean streams. Different thermal requirements were observed for macroinvertebrate families. Optimal monthly mean temperatures estimated for Gripopterygidae (Plecoptera), Hydrobiidae (Gastropoda) and Helicophidae (Trichoptera) were lower than 7 °C, while temperatures for Ameletopsidae, Baetidae (Ephemeroptera), Ecnomidae, Limnephilidae, Hydropsychidae, Leptoceridae (Trichoptera), Elmidae (Coleoptera) and Notonemouridae (Plecoptera) were close to 9.5 °C.According to our estimations, future global warming could cause important changes in the macroinvertebrate composition of Andean watersheds. Gripopterygidae, Austroperlidae, Diamphipnoidae (Plecoptera), Hydrobiidae and Helicophidae (Trichoptera) would be the most vulnerable families under the 2090 temperature predictions due to their preference for low temperature.  相似文献   

长江流域清江胡家溪四种蜉蝣优势种的周年生产量及其动态     

江晶  温芳妮  王利肖  邱爽  李晓宇  闫云君 《湖泊科学》2013,25(1):147-155

2006年4月至2007年3月对长江支流清江二级支流———胡家溪的大型底栖动物群落结构和生产量进行为期一周年的调查和研究.结果表明,主要蜉蝣优势种小裳蜉(Leptophlebia sp.)、扁蜉(Electrogena sp.)、四节蜉(Indobaetis sp.)的生活史为一年三代,细蜉(Caenis sp.)为一年两代;小裳蜉的年均密度和年均生物量分别为407 ind./m2、1.00 g/m2;扁蜉为150 ind./m2、0.37 g/m2,四节蜉为232 ind./m2、0.30 g/m2,细蜉为91 ind./m2、0.17 g/m2.采用龄期频率法测算的周年生产量和P/B分别为:小裳蜉为441.42 g/m2(WW),14.3;扁蜉为434.88 g/m2(WW),7.6;四节蜉为747.21 g/m2(WW),15.0;细蜉为40.52 g/m2(WW),7.2.四种蜉蝣生产量的时间重叠比例相似系数较高,均大于0.55,这可能与四种蜉蝣的生境及食物资源较为相似有关.  相似文献   

The effects of land use at different spatial scales on instream features in agricultural streams     

《Limnologica》2017

The conversion of forests into agriculture has been identified as a key process for stream homogenization. However, the effects of this conversion can be scale-dependent. In this context, our aim was to identify the influence of different land uses at different spatial scales (catchment, drainage network and local) on instream features in agricultural streams. We defined six classes of land use: native forest, reforestation, herbaceous and shrubs, pasture, sugarcane and other categories. We obtained 22 variables related to instream, riparian area, stream morphology and water physicochemical characteristics in 86 stream reaches. To identify and isolate the effect of different land uses at different spatial scales on instream features, we performed a partial redundancy analysis (p-RDA). Different land uses and scales influenced instream features and defined two stream groups: (i) homogeneous streams with a higher proportion of sand substrate and instream grasses that were associated with the proportion of herbaceous vegetation at the local scale and with pasture at all scales and (ii) heterogeneous streams with a higher physical habitat integrity associated with the proportion of forest and sugarcane at the local and catchment scales. Land use at the catchment scale affected the physicochemical water properties and stream morphology, whereas stream physical habitat (i.e., substrate, instream cover, marginal vegetation and stream physical habitat condition) was mainly influenced by land use at the local scale (i.e., 150 m radius). Pure catchment, drainage network and local land uses explained 9%, 7% and 4%, respectively, of the total variation of instream features. Thus, to be most effective, stream conservation and restoration efforts should not be limited to only one scale.  相似文献   

Multi-hazard susceptibility mapping based on Convolutional Neural Networks     

《地学前缘(英文版)》2022,13(5):101425

Multi-hazard susceptibility prediction is an important component of disasters risk management plan. An effective multi-hazard risk mitigation strategy includes assessing individual hazards as well as their interactions. However, with the rapid development of artificial intelligence technology, multi-hazard susceptibility prediction techniques based on machine learning has encountered a huge bottleneck. In order to effectively solve this problem, this study proposes a multi-hazard susceptibility mapping framework using the classical deep learning algorithm of Convolutional Neural Networks (CNN). First, we use historical flash flood, debris flow and landslide locations based on Google Earth images, extensive field surveys, topography, hydrology, and environmental data sets to train and validate the proposed CNN method. Next, the proposed CNN method is assessed in comparison to conventional logistic regression and k-nearest neighbor methods using several objective criteria, i.e., coefficient of determination, overall accuracy, mean absolute error and the root mean square error. Experimental results show that the CNN method outperforms the conventional machine learning algorithms in predicting probability of flash floods, debris flows and landslides. Finally, the susceptibility maps of the three hazards based on CNN are combined to create a multi-hazard susceptibility map. It can be observed from the map that 62.43% of the study area are prone to hazards, while 37.57% of the study area are harmless. In hazard-prone areas, 16.14%, 4.94% and 30.66% of the study area are susceptible to flash floods, debris flows and landslides, respectively. In terms of concurrent hazards, 0.28%, 7.11% and 3.13% of the study area are susceptible to the joint occurrence of flash floods and debris flow, debris flow and landslides, and flash floods and landslides, respectively, whereas, 0.18% of the study area is subject to all the three hazards. The results of this study can benefit engineers, disaster managers and local government officials involved in sustainable land management and disaster risk mitigation.  相似文献