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Butterfly-plant interactions and body size patterns along an elevational gradient in the Manang region of central Nepal

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Journal of Mountain Science 2020年第5期17卷 1115-1127页

作者： Bimal Raj SHRESTHA binu timsina Zuzana MüNZBERGOVá Tomás DOSTáLEK Prakash GAUDEL Tej *** Maan B.ROKAYA Central Department of Zoology Tribhuvan UniversityKathmandu44600Nepal Department of Institute of Environmental Studies/Botany Faculty of ScienceCharles UniversityBenatska 212801 PragueCzech Republic Department of Biodiversity Research Global Change Research CentreCzech Academy of SciencesBelidla 4a60300 BrnoCzech Republic Institute of Botany The Czech Academy of SciencesZamek 125243 PruhoniceCzech Republic

Butterflies are widely studied due to their key ecosystem *** this reason,they are used in ecosystem assessment,formulating conservation plans and in raising the environmental *** of different factors affecting diversity of butterflies is important for their effective *** this study,we investigated abiotic and biotic factors affecting species richness and community composition of butterflies along an elevational gradient in Manang region,central *** also tested if butterfly species follow the Bergmann’s rule.A total of 57 butterfly species belonging to 39 genera and 8 families were recorded in the study *** of a total of 127 plant species identified in the study region,only 67 plant species were visited by butterflies as nectar *** richness of butterflies increased with increasing *** richness was significantly higher in places with shrubs compared to other places and also in autumn than in *** richness of butterflies also depended on composition of plant species occurring at the *** species composition varied among sampling *** was also determined by habitat type,elevation,sampling time,plant species and interactions of elevation×*** relationship between butterfly size and elevation was in the opposite direction than expected according to the Bergmann’s *** conclusion,protection of butterfly diversity can only be achieved by protecting different habitats across the diverse physiography of the region and different plant species,in particular herbs and *** results do not support the Bergmann’s rule for butterflies along an elevational gradient in our region.

关键词： Lepidoptera Microhabitat Species richness Species composition Bergmann’s rule

A Comparison of Local-and Foreign-funded Hydropower Station Construction in Nepal based on Remote Sensing

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Journal of Resources and Ecology 2022年第6期13卷 1009-1021页

作者： timsina Ritu Raj WU Mingquan NIU Zheng State Key Laboratory of Remote Sensing Science Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

International investors in large infrastructure projects face numerous risks. To explore this issue, this paper compares the development of two hydropower stations in Rasuwa District, Nepal: Upper Trishuli 3A, which is fully funded by a Chinese government bank, and Rasuwagadhi, which is fully funded by local government *** construction of these two plants was compared between 2012 and 2020 using a visual interpretation method to extract data on roads, buildings, dams, and vehicles from 1-m-resolution remote sensing imagery. Two methods were used to compare the environmental impacts of each plant. Landsat 7/8 30-m imagery was used to monitor changes in the normalized difference vegetation index around the Upper Trishuli 3A hydropower station from 2012to 2020 and around the Rasuwagadhi hydropower station from 2014 to 2020. Then, 1-m-resolution imagery was used to observe land-cover differences in these areas and time periods. The results indicate that:(1) despite various challenges, such as geological disasters, the COVID-19 pandemic, and a blockade by the Indian government,there was no difference in construction progress between the two hydropower stations.(2) The Upper Trishuli 3A Hydropower Station was associated with better environmental protection work, as there were continuous declines in vegetation growth near Rasuwagadhi and increased overall vegetation growth near Upper Trishuli 3A.(3) Energy projects funded by the Belt and Road Initiative have benefited developing countries enormously. Finally, local conditions should be thoroughly investigated during the construction of foreign-funded power stations.

关键词： the Belt and Road Initiative remote sensing hydropower station Nepal

尼泊尔能源状况及其对经济、环境影响的遥感监测与分析

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尼泊尔能源状况及其对经济、环境影响的遥感监测与分析

作者： Ritu Raj timsina 中国科学院大学(中国科学院空天信息创新研究院)

学位级别：硕士

在过去二十年中,尼泊尔的能源状况有了很大改善。获得电力的人口比例从2000年的28.9%增加到2019年的94.2%。在2008年“国家电力危机解决行动计划”、“十年水电开发计划(2009)”以及第15个社会导向经济政策制定后,尼泊尔政府改变了能源... 详细信息

在过去二十年中,尼泊尔的能源状况有了很大改善。获得电力的人口比例从2000年的28.9%增加到2019年的94.2%。在2008年“国家电力危机解决行动计划”、“十年水电开发计划(2009)”以及第15个社会导向经济政策制定后,尼泊尔政府改变了能源政策,从而使电力供应取得了巨大进展。发电量从2000年的1632GWh发展到2019年的6173GWh,在这一发展过程中,国内和国际捐助者的贡献不容忽视,以尽量减少尼泊尔的电力危机。2000年以来,通过跨境投资或国内投资建设了87座发电站,大大提高了尼泊尔人民在照明、取暖和烹饪等基础设施方面的基本水平,并将农村电气化列为优先事项。同样,尼泊尔对电力部门发展的跨境投资(据统计,电站数量不到10个),加上尼泊尔和其他国家的共同贡献,电站数量攀升至10个水电项目。虽然国内投资的电厂对国民经济增长的影响更大,发电量为6173MW,但国外投资的电厂一直在逐步增加,发电量为388.8MW,略高于联合投资的335MW。尼泊尔政府的二十年发展计划旨在结束尼泊尔的电力危机,直至2050年。尼泊尔的电气化增长率高于全球平均水平0.8%,然而,大多数人口仍然无法获得现代清洁能源,即居住在农村社区和尼泊尔城市部分地区的水电。此外,本研究通过两个水电站(Upper-Trishuli 3A和Rasuwagadhi水电站)的案例研究,调查了外国直接投资(FDI)的影响。Upper-Trishuli 3A的资助机构是一家中国公司,而尼泊尔公司资助了Rasuwagadhi发电站。尼泊尔的这些跨境电力项目在不同层面进行了比较,包括环境影响、社会经济和市场探索以及土地原型。利用遥感数据对水电站从初始开发阶段到竣工阶段的应用进行比较。通过这种方法获得的结果表明,即使在旱季,尼泊尔电力部门的外国投资也可以同样地提高我们的能源需求,我们可以将环境影响降至最低水平,从而为该地区创造更多的市场和经济扩张。同样,对于Bhojpur municipality的Tyamkemaiyum地区,在植被监测和夜间灯光观测中使用卫星数据。中分辨率成像光谱仪(MODIS)卫星的引入在根据用户需求定制遥感数据集方面发挥了重要作用。生成的MODIS产品用于分类归一化植被指数(NDVI),我们将这些值与谷歌地球引擎代码编辑器中的年度马赛克图像相结合。最后,当全国电力过剩率与Tyamkemaiyum的NDVI值耦合时,我们发现,尽管电力过剩率仅为0.03,但植被水平并未下降。结果表明,即使是早期的森林砍伐和人类居住,也会导致该地区部分地区植被的丧失;近年来,由于太阳能和生物能源等其他形式的能源的使用,植树造林得到了大力发展。当通过夜间照明数据防御气象卫星计划(DMSP)和可见红外成像辐射计套件(VIIRS)衡量社会经济发展时,我们观察到,该地区北部的人类住区和基础设施发展的扩张已大大加强,在这些地区创造更光明的价值,并表明Tyamkemaiyum地区的整体繁荣。同样,通过长期检验、自回归分布滞后(ARDL)模型和累积递推残差和平方和检验的增长百分比测量稳定性,观察了城乡人口能源增长百分比对国内生产总值(GDP)的影响。我们获得的最终结果表明,即使我们仅从农村和城市电气化经济指标的部分参数中考虑增长动态,我们也可以预测这些变量对GDP的影响,并且这些变量支持计算长期均衡,并显示一国经济正增长。因此,我们总结说,尼泊尔的能源状况目前已达到稳定状态,但应减少对外国能源进口的依赖,以实现可持续发展目标。这项研究表明,基础设施发展计划落后的国家和经济脆弱的国家可以从外国直接投资中获得显著的好处。开发可再生能源,即使使用废料也可以在国内生产能源,这应该对能源进口造成障碍,以便各国能够在财政上有实力投资于自己的发电资源。在全球范围内,应迅速开展工作,探索可再生能源,因为我们正在慢慢失去煤炭、石油和天然气等基本能源。

关键词：尼泊尔外国直接投资遥感水电站 ARDL CUSUM MODIS VIIRS DMSP

Economics of Nitrogen Use in Cereal Systems in South and East Asia

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Journal of Agricultural Science and Technology 2011年第1期5卷 1-13页

作者： X. Y. Li J. timsina J. Dixon Impacts Targeting and Assessment Unit International Maize and Wheat Improvement Center （CIMMTT） apdo postal 6-64106600 Mexico DF Mexieo International Rice Research Institute （IRRl）-Bangladesh Office Banani DOHS 1206 Dhaka Bangladesh Australian Centre for International Agricultural Research （A CIAR） GPO Box 15 71 Canberra ACT 2601 Australia

A literature survey and focused interviews with experienced agronomists and socio-economists from south, east, and southeast Asian countries were conducted to determine physical and economic relationships of cereal yields and N use, using partial factor productivity （PFP） and nitrogen （N） response functions, while considering the impacts of （N） and crop grain prices. The data were drawn from FAOSTAT, World Bank, and survey results from those countries. Rice has the greatest PFP-N （70 kg grain kg^-1 N）, wheat a moderate （57 kg grain kg^-1 N）, and maize the lowest PFP-N （52 kg grain kg^-1 N） at current application levels. At potential optimal N use rates, estimates for PFP-N were 26 kg grain kg^-1 N for maize, 25 kg for rice and 16 kg for wheat. Assuming a constant average PFP-N （30 kg grain kg^-1 N） for these cereals, it is estimated that 13 Mt N would be needed to meet a projected food demand by 2020 assuming no use of other additional inputs. Assuming a 20% increase in nitrogen use efficiency （NUE） to 36 kg grain kgl N, 10.6 Mt would be needed to meet the food demand, implying an annual growth rate in N use of 1.25%. It is concluded that economically optimal N rates are relatively insensitive to changes in prices of N and cereal grain. Key interventions to improve sustainable food security include increasing N fertilizer use, improving NUE, and reducing environmental impacts.

关键词： Nitrogen cereal system crop yield physical optimum economic optimum Asia.

Effect of Biofertilizer on Growth, Productivity, Quality and Economics of Rainfed Organic Ginger （Zingiber officinale Rosc.） Bhaisey cv. in North-Eastern Region of India

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Journal of Agricultural Science and Technology(A) 2013年第2期3卷 83-98页

作者： Nongmaithem Jyotsna Mainak Ghosh Dulal Chandra Ghosh Wahengbam Ingo Meitei Jagadish timsina College of Agriculture Central Agricultural University Imphal Manipur 795001 India Department of Agronomy Bihar Agricultural University Bihar 813210 India Institute of Agriculture Visva-Bharati Sriniketan-731236 West Bengal India IRRI-Bangladesh Office Banani DOHS Dhaka-1206 Bangladesh

Ginger yields in the NorthEastern region of India are low because the extremely poor farmers of the region can not afford to apply any chemical fertilizers and hence apply only the locally-available farmyard manures to ginger fields. Biofertilizers may be a cheap source of fertilizers for ginger cultivation as they can increase nutrient availability and improve rhizome quality and are required in small quantity. An investigation was thus undertaken to study the effect of different biofenilizers on growth, productivity, quality and economics of organic ginger grown under rainfed condition in NorthEastern region of India. Seed treatment with biofertilizers enhanced growth, increased rhizome yield by 19.0% and resulted in 32.4% higher net profit over control. Among the seed treatments, Azotobacter 5.0 kg ha＂l, Azospirillum 3.75 kg hal and Phosphotica 3.75 kg ha-1 were found optimum in improving most of the growth attributes, increasing yield components and yield of rhizome by 5.6%-13.5%. They also improved rhizome quality by increasing specific gravity, oleoresin and dry matter content and by decreasing crude fibre in rhizome. They resulted in higher net return by 4.0%-12.0% as compared to their other levels. Combined use of Azotobacter 5.0 kg hal along with Phosphotica 3.75 kg ha＂l was found to be the best treatment combination which greatly improved growth and yield attributes of ginger and ultimately recorded markedly higher productivity （2.0%-23.5%） over other combinations. This treatment combination improved the quality of the produce and resulted in the highest gross return （$4,905 hal）, net return （$3,525 hal） and return per dollar （3.55） invested in ginger cultivation. It appears that growing organic ginger by treating the seed rhizome with Azotobacter 5.0 kg ha-~ along with Phosphotica 3.75 kg ha-1 can result in good growth and high productivity of improved quality rhizome and ultimately result in maximum net profit and thus can be recommended for the NorthEas

关键词： Biofertilizers growth productivity quality economics ginger (Zingiber officinale Rosc.).

Effect of Integrated Nutrient Management on Growth and Productivity of Hybrid Rice

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Journal of Agricultural Science and Technology(B) 2015年第5期5卷 297-308页

作者： Spurti Mondal Malavathu Mallikarjun Mainak Ghosh Dulal Chandra Ghosh Jagadish timsina Institute of Agriculture Visva-BharatL Sriniketan-731 236 West Bengal India Department of Agronomy Bihar Agricultural University Sabour Bihar 813 210 India The University of Melbourne 156-292 Grattan St. Parkvile Victoria 3010 Australia

Sustaining rice （Oryza sativa L.） productivity at high level is a great challenge, particularly in areas where rice productivity declines in spite of following recommended nutrient management practices. Nutrient management by integrating organic manures, inorganic fertilizers and biofertilizers may play an important role in improving and sustaining rice productivity. In this study, the authors tried to evaluate the suitable proportion of organic manures and inorganic fertilizers along with biofertilizer to maximize growth and productivity of hybrid rice on sandy-loam lateritic soils of West Bengal, India. The crop having 50% recommended dose of fertilizer （RDF）＋ 50% recommended dose of nitrogen （RDN） through mustard oil cake （MOC） and 75% RDF ＋ 25% RDN through MOC ＋ biofertilizer significantly increased plant height, number of tillers/m2, leaf area index （LAI）, dry matter accumulation （DMA） and crop growth rate （CGR） at initial and vital period of grain growth over those of 25% RDF ＋ 75% RDN through MOC and 100% RDN through MOC. The former two treatments also increased number of panicles/m2 and number of grains/panicle over those of only organic manuring （100% RDN） or only chemical fertilization （100% RDF） or 25% RDF ＋ 75% RDN through MOC. Crop with 75% RDF ＋ 25% RDN through MOC ＋ biofertilizer or 50% RDF ＋ 50% RDN through MOC produced 20.2%-33.8% higher grain yield and 11.0%-33.3% greater straw yield, and paid higher gross and net returns over other treatments. This study suggests growing hybrid rice with 75% RDF ＋ 25% RDN through MOC ＋ biofertilizer or 50% RDF ＋ 50% RDN through MOC for better growth, higher productivity and greater profit.

关键词： Hybrid rice biofertilizer imegrated nutrient management.

Effect of Biofertilizer on Biomass Productivity, Nutrient Balance and Soil Fertility in Rainfed Organic Ginger Production System

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Journal of Agricultural Science and Technology(A) 2013年第1期3卷 10-19页

作者： Nongmaithem Jyotsna Mainak Ghosh Dulal Chandra Ghosh, Wahengbam Ingo Meitei Jagadish timsina College of Agriculture Central Agricultural University Imphal Manipur 795001 India Department of Agronomy Bihar Agricultural University Sabour 813210 Bihar India Institute of Agriculture Visva-Bharati Sriniketan 731236 West Bengal India IRRI-Bangladesh Office Banani DOHS Dhaka 1206 Bangladesh

Farmers of North-Eastern India grow ginger organically and obtain low yield. Biofertilizer may help in increasing yield and maintaining soil fertility. An investigation made with different biofertilizers showed that seed treatment with biofertilizer increased biomass by 18.3%, enhanced N, P and K removal and improved short-term soil fertility status by increasing N and P balance and reducing negative K balance over control plots. Use of high dose （5.0 kg haL） of Azotobacter （a3） and medium dose （3.75 kg hal） of both Azospirillum （b2） and Phosphotica （c2） increased rhizome biomass by 6.8%-12.5% and shoot biomass by 5.6%-14.3% over other levels. They enhanced N, P and K removal by both rhizome and shoot when compared with other levels. The above biofertilizer treatments improved organic carbon and available N and P status of the soil by increasing N and P balance. The result showed overall strong negative K balance; but biofertilizer treatments greatly reduced the negative K balance in soil as compared to the control plots. Seed treatment with high level of Azotobacter along with medium level of Phosphotica （a3c2） produced the highest biomass yield （7.4 t hal）, increased N and P balance and fertility status in spite of hizh N, P and K removal.

关键词： Biofertilizer ginger productivity nutrient balance soil fertility.

Maize-rice cropping systems in Bangladesh： Status and research needs

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Journal of Agricultural Science and Technology 2009年第6期3卷 35-53页

作者： M. Yusuf Ali S. R. Waddington J. timsina D. Hodson J. Dixon On-Farm Research Division Bangladesh Agricultural Research Institute Gazipur 1701 Bangladesh CIMMYT Dhaka 1212 Bangladesh IRRI-Bangladesh Office Dhaka 1212 Bangladesh CIMMYT Apdo Postal 6-641 06600 Mexico DF Mexico

Maize-rice cropping systems are expanding in Bangladesh. Hybrid maize has increasing demand and value, particularly for poultry feed, while rice remains the traditional dominant starch staple food. Bangladesh maize yields （with average farm yields around 5.7 t·ha^-1） are among the highest found in Asia. Cool winter （Rabi） season maize followed by T. Aman （monsoon） rice is the major cropping system; however it is now becoming diversified with many other crops including potato. Financially, hybrid maize is far more profitable than boro （irrigated） rice, wheat, or most other competing winter season Rabi crops. Although maize is relatively problem-free in Bangladesh, some constraints are intensifying with increased concern over input supply and soil-related environmental sustainability. An array of new technologies for sustainable intensive maize production systems is emerging in Bangladesh and some are being promoted and adopted. Continued sustainability of hybrid maize production in Bangladesh depends on optimization of planting time, quality seed of appropriate hybrids, balanced use of nutrient inputs along with soil fertility conservation and other management, for which further research would be high priority.

关键词： maize-rice Bangladesh problems and risks promising technologies research needs

Economic Analysis of Diversified Rotational Cropping Systems in the Lateritic Belt of Lower Gangetic Plain of Eastern India

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Journal of Agricultural Science and Technology(B) 2011年第3期1卷 331-341页

作者： D. Mandal K. Baral D. C. Ghosh J. timsina M. K. Dasgupta Uttar Dinajpur Krishi Vigyan Kendra （Uttar Banga Krishi Viswavidyalaya） Chopra-733216 Uttar Dinajpur West Bengal Palli-Siksha Bhavana Institute of Agriculture Visva-Bharati Sriniketan-731236 Birbhum West Bengal IRRI-Bangladesh Office Dhaka 1206 Bangladesh

Economic analysis of different diversified rotational cropping systems under Farmers＇ package/practices and improved package/practices was conducted in Birbhum district, West Bengal, located in the red and lateritic belt of lower Gangetic plain of eastern lndia. Diversified triple cropping systems （peanut-brinjal＋brinjal, rice-potato-pumpkin, and cucumber-cabbage-basella） required higher cost for cultivation, but also produced higher rice equivalent yield, higher net return and higher return rupee1 invested in both management practices. Considering the resource-ability and risk-bearing capacity, and net return and return rupee^-1 （RPR） invested, these cropping systems can be recommended for resource-rich farmers. Rice-rapeseed-cowpea, rice-wheat-green gram and radish-tomato-amaranthus systems profitable. These cropping systems can be required less inputs for cultivation, were less risky, and economically viable and recommended for resource-poor farmers. Peanut-brinjal ＋ brinjal-okra-chilli ＋ chilli-cucumber-cabbage-basella system was the best among all the 3-year rotational systems in respect to RPR in both management practices. This rotational system will be suitable for resource-rich farmers. Vegetable-based rotational systems （ridge gourd-marigold-okra-black gram-pointed gourd ＋ pointed gourd-radish-tomato-amaranthus） or rice-based rotational system （rice-wheat-green gram-rice-rapeseed-cowpea-rice-potato-pumpkin） also found to be suitable to increase the profitability and system sustainability. These cropping systems can be recommended for all groups of farmers.

关键词： Cropping systems rotational cropping systems productivity economics west Bengal India.