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The reproductive biology of a Central American cichlid Neetroplus nematopus in Lake Xiloá ,Nicaragua

Current Zoology 2010年第1期56卷 43-51页

作者： Kenneth R.McKAYE Jeremy HALE Eric P.van den BERGHE world wide fund for nature finland Universidad de Centroamericana Department of Mathematics Science and Technology Ave Maria University Latin American Campus

This study was conducted to provide a five-year database on the breeding seasonality and breeding biology of a Central American cichlid fish Neetroplus nematopus, a biparental substratum-spawning cichlid that cares for its eggs, wrigglers, and fry for up to six weeks. A total of 503 breeding pairs were monitored for breeding success. Breeding pairs of N. nematopus are sexually dimorphic in size, with females averaging 39% of male body mass. Fry emerged from 85% of nesting cavities. After three weeks, only 30% of the broods were present in the nesting cavity; these broods had a 30% survival rate, giving a 9% overall survival rate. Nineteen percent of the successful parents with three-week-old broods adopted foreign fry. A consistent unimodal breeding peak in December was observed for five years. This breeding peak differed dramatically from the bimodal breeding season 20 years found in the 1970s. The effects of extensive grenade fishing practices during the 1980s might have played a substantial role in the observed change. Grenade fishing stopped in 1991, and the number ofN. nematopus pairs increased by 136% from 1990 to 1995. With increased density of breeding fish, the breeding season for this species also expanded. The balance between divergent selection due to competition for breeding sites and stabilizing selection due to predation pressure on offspring is likely to mold the breeding season for N. nematopus and other cichlids of Lake Xilofi. We suggest that brood adoption and synchrony of breeding is a strategy to reduce predation on the parent＇s own young [Current Zoology 56 （1）： 43-51 2010].

关键词： Nicaragua Cichlids Breeding Reproduction Synchrony Seasonality

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The effects of prey depletion on dietary niches of sympatric apex predators in Southeast Asia

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Integrative Zoology 2021年第1期16卷 19-32页

作者： Robert STEINMETZ Naret SEUATURIEN Pairoj INTANAJITJUY Pichet INRUEANG Kittipat PREMPREE world wide fund for nature-Thailand BangkokThailand and 2 Kuiburi National ParkPrachuapkirikhanThailand

Resource depletion exerts opposing pressures on co-occurring consumers to expand diets while limiting overlap with *** foraging theory as a framework,we tested the effects of prey availability on diet spe-cialization and overlap among competing Asian predators:dhole,leopard,and *** used scat analysis from a prey-poor site,combined with a quantitative synthesis of 40 other diet studies,to determine biomass of different prey types consumed by each *** then assessed diet composition in relation to prey density,and compared diet breadth and overlap between prey-poor and prey-rich *** prey rich areas,all three predators specialized on energetically profitable medium and large ungulates(>30 kg),resulting in narrow,overlapping *** predator shifted toward less profitable small-bodied prey(≤30 kg)as preferred ungulates declined,whereas con-sumption of preferred ungulates was unrelated to small prey abundance,as predicted by foraging *** breadths doubled under prey depletion(except leopard),but overlap declined as diets diverged via species-specific traits that facilitated capture of different types of alternative ***’s apex predators adapt similarly to depletion of mutually preferred ungulates by switching to more numerous but less profitable small *** they can also partition a depleted prey base through intrinsic niche differences,thereby avoiding competitive *** find-ings illuminate the stabilizing properties of adaptive foraging and niche differences in ecological communities,and provide insights into the behavior and resilience of Asia’s endangered apex predators in response to prey depletion in the heavily poached forests of this region.

关键词： coexistence dhole leopard niche overlap optimal foraging theory

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Robinia pseudoacacia leaves improve soil physical and chemical properties

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Journal of Arid Land 2010年第4期2卷 266-271页

作者： Babar KHAN Abdukadir Ablimit Rashed MAHMOOD Muhammad QASIM world wide fund for nature Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences COMSATS Institute of Information Technology

The role of the leaves of Robinia pseudoacacia L., which is widely distributed in the arid lands, on improving soil physical and chemical properties was analyzed at various incubation periods. The incubated soils added with 0, 25, 50 and 75 g Robinia pseudoacacia leaves were tested after consecutive incubation intervals of 6, 8 and 10 months and the different soil parameters were measured. The results showed the increases in organic matter (OM), extractable K, cation exchange capacity (CEC), aggregate stability and water holding capacity, but the decreases in pH value and bulk density after 6 months’ incubation. The gradual decrease in change rates of soil properties indicated less microbial population and organic residual mineralization under acidic conditions, which were resulted from fast decomposition of leaves after the first 6 months incubation. The increases in soil organic matter content, extractable K, CEC, aggregate stability and water holding capacity and the decreases in soil pH and bulk density provide favorable conditions for crop’s growth.

关键词： soil physical and chemical properties Robinia pseudoacacia Gilgit-Baltistan

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Analysis of deposition and erosion of Dongting Lake by GIS

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Journal of Geographical Sciences 2001年第4期11卷 22-30页

作者： Gao Jun-feng Zhang Chen Jiang Jia-hu Huang Qun Nanjing Institute of Geography Limnology CAS world wide fund of nature

The sediments of the Dongting Lake come from four channels (one of them was closed in 1959), connected with the Yangtze River, four tributaries (Lishui, Yuanjiang, Zishui and Xiangjiang) and local area, and some of them are transported into the Yangtze River in Chenglingji, which is located at the exit of the Dongting Lake, some of them deposit into drainage system in the lake region and the rest deposit into the lake. The annual mean sediment is 166,555x104 t, of which 80% come from the four channels, 18% from the four tributaries and 2% from local area, whereas 26% of the total sediments are transported into the Yangtze River and 74% deposited into the lake and the lake drainage system. Based on topographic maps of 1974, 1988 and 1998, and the spatial analysis method with geographic information system (GIS), changes in sediment deposition and erosion are studied in this paper. By overlay analysis of 1974 and 1988, 1988 and 1998, erosion and sediments deposition areas are defined. The main conclusions are: (1) sediment rate in the lake is larger than erosion rate from 1974 to 1998. The mean deposition in the lake is 0.43 m; (2) annual sediment deposition is the same between 1974-1988 and 1988-1998, but the annual volume of deposition and erosion of 1988-1998 is bigger than that in 1974-1988; (3) before the completion of the Three Gorges Reservoir, there will be 7.82x108 m3 of sediments deposited in the lake, which would make the lake silted up by 0.33 m; (4) in the lake, the deposition area is found in the north of the east Dongting Lake, the south-west of the south Dongting Lake, and the east of the west Dongting Lake; while the eroded area is in the south of the east Dongting Lake, the middle of the south Dongting Lake, the west of the west Dongting Lake, as well as Xiangjiang and Lishui river flood channels.

关键词： Dongting Lake sediment deposition and erosion spatial distribution GIS

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Range extension of four highland agamid lizards in Shimshal Pamir,Pakistan

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Journal of Arid Land 2012年第1期4卷 77-84页

作者： Babar KHAN Waseem AHMED Abdukadir Ablimit Shamim FAKHRI Hassan ALI Pakistan Wildlife Foundation Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences world wide fund for nature Pakistan Zoological Survey Department

As part of the Sino-Pak trans-boundary cooperation for conservation and sustainable development in Pamir border region, world Wild fund （WWF）-Pakistan conducted a preliminary social, economic and ecological survey in the ShimshaI-Pamir Lakes area in July 2009. The purpose of the study was to explore potentials and opportunities for future collaborative conservation of some species, habitats and high altitude ecosystems in the border region between China and Pakistan. The two-week herpetological study in the Shimshal Pamir area of Khunjerab National Park （KNP） along Pakistan-China border was an integral part of the survey, conducted exclu- sively to document reptilian fauna with a special emphasis on investigating their occurrence, distribution and status in the study area. Field investigations were performed during daytime when it was hot enough and reptiles were active, basking or feeding. A total of 15 specimens belonging to four species of the Agamidae family were captured by striking stones and beating bushes with sticks. Collected specimens were preserved using 10% formalin solution, tagged with field information and stored in Zoological Survey Department, Karachi for future reference. Laboratory investigations were carried out for pholidosic counts and morphometric measurements. A detailed review of relevant literature, habitat characteristics and laboratory investigations revealed the occurrence of Laudakia himalayana, L. pakistanica, L. tuberculata and L. badakhshana at 4,082 m, 4,172 m, 4,005 m and 4,240 m asl, respectively, which are much higher altitudes as compared to the previously reported heights of 3,353 m, 3,200 m, 2,500 m and 2,400 m asl. The terrain offers a variety of ecological barriers, in the form of fast and freezing running waters and massive glaciers with peculiar harsh climatic conditions prevailing for nine months of the year, which restricts species migration and thus increases endemism. Although one of the four species recorded from the

关键词： Laudakia himalayana L. pakistanica L. tuberculat L. badakhshana Agarnidae Gilgit-Baltistan Khunjerab National Park Pakistan

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Forest Cover Change Assessment in Conflict-affected Areas of Northwest Pakistan: the Case of Swat and Shangla Districts

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Journal of Mountain Science 2012年第3期9卷 297-306页

作者： Faisal Mueen QAMER Sawaid ABBAS Rashid SALEEM Khurram SHEHZAD Hassan ALI Hammad GILANI world wide fund for nature(WWF)Pakistan LahorePakistan International Centre for Integrated Mountain Development(ICIMOD) KathmanduNepal Asian Institute of Technology BangkokThailand

This study examines the spatial and temporal forest cover changes in Swat and Shangla districts to understand the deforestation pattern in context of the recent security conflict in these districts. We used multi-resolution satellite images to assess the long term deforestation from 2001 to 2009 and also to identify episodic forest cutting areas appeared during the conflict period of Oct. 2007 - Oct. 2008. There are only 58 ha of deforestation identified during the conflict period while 1268 ha of gross annual deforestation were assessed during last eight years. Most of the deforestation patches persist around the administrative boundaries at sub-district levels (tehsils) which can be attributed to ambiguity in unclear jurisdiction between the forest official. The results highlight that the forest cutting appeared in Swat and Shangla during the conflict period is not as significant when compared with the long term deforestation pattern in the area. On the one side the results of the study are supportive to the picture that emerges from international studies which report high rate of deforestation in the country and on the other side it negates any relation between the security situation and the increasing deforestation in the north western Pakistan. The study concludes that deforestation assessments require verification by independent sources of data, such as satellite imagery to improve our understanding of deforestation processes.

关键词： Forest cover change Deforestation Conflict-affected area GIS Pakistan

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Evaluation of state and community/private forests in Punjab, Pakistan using geospatial data and related techniques

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Forest Ecosystems 2015年第2期2卷 155-167页

作者： Naeem Shahzad Urooj Saeed Hammad Gilani Sajid Rashid Ahmad Irfan Ashraf Syed Muhammad Irteza world wide fund for nature (WWF) Institute of Geology University of the Punjab International Centre for Integrated Mountain Development (ICIMOD) Department of Land Surveying and Geo-Informatics Hong Kong Polytechnic University

Background： Forests are fundamental in maintaining water supplies, providing economic goods, mitigating climate change, and maintaining biodiversity, thus providing many of the world＇s poorest with income, food and medicine. Too often, forested lands are treated as ＂wastelands＂ or ＂free＂ and are easily cleared for agricultural and infrastructure expansion. Methods： In this paper, the sustainability of two forest ecosystems （state and community/private owned） was evaluated using SPOT-5 satellite images of 2005 and 2011. This study was conducted in a sub-watershed area covering 468 km2, of which 201 km2 is managed by the state and 267 km2 by community/private ownership in the Murree Galliat region of Punjab Province of Pakistan. A participatory approach was adopted for the delineation and demarcation of forest boundaries. The Geographic Object-Based Image Analysis （GEOBIA） technique was used for identification and mapping of ten Land Cover （LC） features. Results： The results show that between the years 2005 to 2011, a total of 55 km2 （24 km2 in state-owned forest and 31 km2 in community/private forest） was converted from forest to non-forest. The conclusion is that conservation is more effective in state-owned forests than in the community/private forests. Conclusions： These findings may help to mobilize community awareness and identify effective initiatives for improved management of community/private forest land for other regions of Pakistan.

关键词： Forest management SPOT-5 satellite images State and community/private owned forests Murree Galliat Pakistan

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Taxonomy,distribution,and contemporary exposure of terrestrial mammals to floods and human pressure across different areas for biodiversity conservation in China

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Integrative Zoology 2024年第3期19卷 458-467页

作者： Roman SHARNUUD Eric I.AMECA MOE Key Laboratory for Biodiversity Science&Ecological Engineering College of Life SciencesBeijing Normal UniversityBeijingChina Climate Change Specialist Group Species Survival CommissionInternational Union for Conservation of NatureGlandSwitzerland

A significant research focus is placed on identifying animal species and areas at future risk to human-induced alterations of the environment and long-term changes in climatic ***,the extent to which exposure to extreme climatic events and intense human pressure can increase the risk of harmful impacts on species remains poorly *** on terrestrial mammals in China,one of the world’s megadiverse countries,we investigated patterns of contemporary exposure to floods and human pressures and determined their taxonomic representation and distribution across three major area-based conservation schemes,namely,national nature reserves(NNRs),priority areas for biodiversity conservation(PABCs),and key biodiversity areas(KBAs).Among the 440 species assessed with moderate or high exposure to floods,327(∼75%)also qualified as moderate or high in exposure to intense human *** species mainly belong to the orders Chiroptera,Eulipotyphla,and ***,there were 305,311,and 311 species with moderate or high exposure to flood and intense human pressure represented across NNRs,PABCs,and KBAs,*** findings support the prioritization of KBAs for expansion of site-based protection efforts such as NNRs in China,considering threats to species from exposure to adverse effects from both extreme climate and human pressure.

关键词： conservation floods human pressure mammals taxonomy

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High-resolution photogrammetry to measure physical aperture of two separated rock fracture surfaces

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 2922-2934页

作者： Masoud Torkan Mateusz Janiszewski Lauri Uotinen Alireza Baghbanan Mikael Rinne Department of Civil Engineering Aalto UniversityEspooFinland Department of Mining Engineering Isfahan University of TechnologyIsfahanIran

Photogrammetry,reconstructing three-dimensional(3D)models from overlapping two-dimensional(2D)photos,finds application in rock mechanics and rock engineering to extract geometrical details of reconstructed objects,for example rock *** properties are important for determining the mechanical stability,permeability,strength,and shear behavior of the rock *** can be used to reconstruct detailed 3D models of two separated rock fracture surfaces to characterize fracture roughness and physical aperture,which controls the fluid flow,hydromechanical and shear behavior of the rock *** research aimed to determine the optimal number of scale bars required to produce high-precision 3D models of a fracture surface.A workflow has been developed to define the physical aperture of a fracture using *** blocks of Kuru granite(25 cm×25 cm×10 cm)with an artificially induced fracture,were *** scaling 3D models,321 markers were used as ground control points(GCPs)with predefined distances on each *** the samples were wellmatched in their original positions,the entire block was *** data of the GCPs were extracted from the 3D model of the *** half was surveyed separately and georeferenced by GCPs and merged into the same coordinate *** fracture surfaces were extracted from the 3D models and the vertical distance between the two surfaces was digitally calculated as physical *** assessment of the photogrammetric reconstruction showed a 20-30 mm digital control distance accuracy when compared to known distances defined between *** attain this accuracy,the study found that at least 200 scale bars were ***,photogrammetry was employed to measure changes in aperture under normal *** results obtained from this approach were found to be in good agreement with those obtained using linear variable displacement transducers(LVDTs),with differences ran

关键词： Photogrammetry Physical aperture Rock fracture Predefined distances Markers

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Foraging valor linked with aggression:selection against completely abandoning aggression in the high-elevation ant Tetramorium alpestre?

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Insect Science 2024年第3期31卷 953-970页

作者： Marie-Luise Contala Patrick Krapf Florian M.Steiner Birgit C.Schlick-Steiner Molecular Ecology Group Department of EcologyUniversitat InnsbruckInnsbruckAustria rganismal&Evolutionary Biology Research Programme University of HelsinkiHelsinkiFinland

Aggression has multiple benefits and is often coupled with other behaviors("behavioral syndromes").The level of aggressiveness is influenced by an adaptive benefit-cost ratio suggesting that benefits should outweigh the costs of ***,we assess if several behaviors are coupled in two behaviorally different populations(aggressive,peaceful)of the high-elevation ant Tetramorium *** three weeks,we collected colony fragments and analyzed boldness,exploring,foraging,and risk-taking *** hypothesized that the aggressive population is bolder,more explorative and risk-prone,and forages more food than the peaceful *** test whether(a)the combination of experiments and parameters used yields a good setup,(b)populations differ behaviorally,and(c)populations display behavioral syndromes,we assessed(a)the frequency of repeatable behaviors of each experiment,(b)the behavioral means among populations,and(c)the behavioral repeatability,*** found that(a)boldness and exploring were most repeatable and represent a good experimental setup,(b)the aggressive population was bolder and more explorative and risk-prone than the peaceful population,(c)boldness and exploring behaviors were highly repeatable in both populations,thus corroborating our *** results suggest that boldness,exploring,and risk-taking but not foraging are presumably coupled with aggression and indicate the presence of behavioral syndromes in this *** specific ecological conditions,aggression may be coupled with other behaviors and important for finding *** is probably adaptive in ***,possibly indicating that selection favors aggression at least partially,which may counteract the complete loss of intraspecific aggression.

关键词： adaptive value behavioral syndromes boldness exploration repeatability trade-off

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