Sanu Maharjan

The predicted increasing atmospheric carbon dioxide (CO2) level is responsive to altering the future climate, and a small change in the soil carbon may significantly affect the forest carbon cycle and climate system. Soil respiration (SR) and its influencing factors like soil temperature (ST), soil water content (SWC) and surface litter-fall were measured monthly over one year in a sub-tropical Pine (Pinus roxburghii) forest of Bhaktapur district located in central Nepal to determine the SR of the forest and, its variations and sensitivity. The results showed that SR varied to the changes in ST by an exponential significant positive correlation between them. The optimum SR was observed between 10 and 22ºC, and the highest SR were obtained above ST at 20ºC. The temperature sensitivity value of SR (Q10) was estimated at Q10 = 2.13. The significant exponential curve represented the effect of SWC on SR. The higher SR rate was mostly measured between 10 and 25% SWC. The monthly and seaso...

Prevailing climate change is expected due to carbon dioxide emission to the atmosphere through soil respiration and perhaps the alteration in the terrestrial carbon cycle. The measurements to establish the effect and sensitivity of soil temperature, soil water content and plant biomass on soil respiration was performed in the sub-tropical grassland located in Central Nepal. Field measurements of soil respiration was conducted by using the closed-chamber method, and soil temperature, soil water content and plant biomass were monitored in the years 2015 and 2016. The soil respiration showed positive significant exponential function which accounted for 74.6% (R2=0.746, p<0.05) of its variation with the soil temperature. The temperature sensitivity of soil respiration, Q10 value obtained was 2.68. Similarly, soil respiration showed a positive significant exponential function that accounted for 37.2% (R2=0.372, p<0.05) of its variation with the soil water content. Remarkable season...

Monitoring study was carried out through survey in Kathmandu valley (Ramkot -5 Kathmandu district, Katunje -5, Bhaktapur district and Bungmati -25 Lalitpur district). Both qualitative and quantitative research approach was use with an objective to find the insect pests of maize in Kathmandu valley. Survey information was collected from 100 households randomly; 33 households from Kathmandu and Lalitpur districts and 34 households from Bhaktapur district during mid - June 2017 to mid - September 2017 along with maize field survey from respondent’s field. Sets of questionnaires were prepared to acquire the primary information from maize growers through face to face interview method. Secondary data collection was done from gleaning the reports, publications of different organizations, websites and libraries. This survey primarily focused on maize pest diversity in Kathmandu valley and their management practices adopted by the farmers, and secondarily on socio-economic condition of peopl...

Increased human pressure and urbanization has led into the formation of forest islands in the Kathmandu valley. Bhandarkhal forest (area: 6.75 ha), situated in the eastern part of Pashupati area represents a typical such forest Kathmandu. The sandy loam soil in the forest is described as characteristic of lacustrine sediments. The soil was slightly acidic with pH 5.4, and contained organic matter 6.3%, nitrogen 0.29%, phosphorous 821 kg/ha, and potassium 1171 kg/ha. Over 35 species were recorded at the tree stratum (>4m height). The most frequently seen trees at the stratum were Zizyphus incurva , Stralzvaesia nussia , Ilex excelsa and Persea duthiei . At the shrub stratum (1-4m height), the most frequently occurring shrub species were Clredertdron viscosum , Sarcococca coriacea , Xylosma controversum and Murraya exotica . The ground coverage of the forest was above 70% in average except in some few places. The most frequently occurring species at the ground stratum (<1 m heig...

ASSESSMENT OF CARBON STOCK IN GOKARNA FOREST, KATHMANDU, NEPAL Sagar Dhakal*, Sanu Raja Maharjan, Prakash C Aryal *Correspondence: sagardhakal2043@gmail.com 1 Department of Environmental Science, GoldenGate International College, Kathmandu, Nepal Abstract Assessment of carbon stock in urban forest is essential to obtain the carbon sequestration rate and has important role in urban environment with play vital role to conserve biodiversity. This study was conducted in Gokarna protected forest, Kathmandu, to explore the forest carbon stock. A total of 60 circular plots of random sample with size of 250 m were sampled for study. The biomass of standing trees was estimated by using allometric equation of trees, measuring their diameter & height. A total of 844 trees were measured belonging to 52 species. The total tree biomass was found to be 548.92t/ha. The aboveground tree carbon and belowground tree carbon were found 214.99 (t/ha) and 42.99 (t/ha) respectively. On the basis of IVI val...

The growth of urban population in Kathmandu has resulted in increased degradation of its forests and consequently increased recreational pressure on them. Ranibari forest (area 7.6 ha), situated at the north west region of Kathmandu valley represents a typical such forest in Kathmandu. Quantitative study was carried to assess the structural dimensions and analyze community structure of the forest. Samplings were done in 26 large quadrats (size: 25mx25m) for canopy stratum, 52 medium plots (size: 5mx5m) for understory stratum and 130 small plots (size: 1mx1m) for the study of ground vegetation. The forest was floristically rich with a total of 108 species belonging to 58 families and 92 genera. The canopy stratum was predominated by dense clumps of bamboos and tree species of regional flora such as Zizyphus incurva, Stranvaesia nussia, Persea duthiei, Engelhardtia spicata, Celtis australis, and Schima wallichii. The shrub vegetation was relatively poor, dominated by invasive alien La...

ABSTRACT With the increased loss of plant biodiversity, the Ex situ seed conservation has become of strategic importance. International treaties and conventions encourage more developed countries to cooperate in providing financial and other supports for the establishment and maintenance of Ex situ conservation facilities in developing countries. In this regard, the Nepal Academy of Science and Technology (Nepal) and the Ev-K2-CNR (Italy) set up the Himalayan Seed Bank, with the goal of establishing Ex situ seed conservation facility of rare, endemic and endangered plants in Nepal. Here, we discuss the importance of training on seed curation, management and research for the seed bank operators in developing countries. Particular attention is given to the procedures for providing power supply and for optimizing seed longevity in dry storage. Finally, the importance of duplicates in high-standard international seed banks is also discussed.