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Impact of agroforestry intervention on farm income under the subsistence farming system of the middle hills, Nepal 总被引：2，自引：0，他引：2
Practices that minimize the rate of soil degradation, increase crop yields and raise farm income are key to sustaining agricultural productivity in the hills of Nepal. The use of farmland is undergoing rapid changes in response to increasing population pressure, deforestation and subsistence needs. Against this background, this study examined the impact of an agroforestry intervention project on farm income based on a sample of subsistence farm households in Dhadhing district. The project was implemented by Nepal Agroforestry Foundation in 1993/94 to increase fodder production through the promotion of agroforestry. A total of 223 households (82 with project and 141 without project) were interviewed during May–October 1998 to collect information on production and agroforestrys' impact on farm income. The benefit-cost analysis showed that the agricultural system including agroforestry was more profitable than the conventional one. The results also showed that the introduction of mulberry trees for sericulture could further enhance the profitability of an agroforestry-based system. Thus, agroforestry has great potential for enhancing food production and farmers' economic conditions in a sustainable manner through its positive contributions to household income.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
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Managing urban population and environment has been one of the most important challenges recently. This paper attempts to assess the existing practices, people's perception, gaps and ways forward for participatory urban forestry and aims to help promote UF through identifying the current status, future prospects for and peoples’ perception about UF in two cities of Nepal. The study was conducted in Pokhara sub-metropolitan city and Bharatpur municipality of Nepal. Total numbers of plants in the effective green spaces are estimated as 285,500 in Pokhara and 213,250 in Bharatpur, and the number of tree species was 62 and 52 respectively. The religious tree species – Ficus bengalensis and Ficus religiosa are the most common and hazardous in both cities. The urban people have preferred small, less branchy and attractive tree species. However, the choice of existing species is inappropriate and not according to the people's interest. Therefore, urban people are unsatisfied with the existing species and their frequencies. The municipal authorities and other related organizations do not have any specific plan, programs and activities nor is there any public involvement to promote urban forestry. Regular coordination, cooperation and monitoring are required for the involvement of various stakeholders such as municipality, government office, community organizations and urban people. Analysis further shows that people's perception on urban forestry is encouraging as most of them agreed that the urban forests are useful for addressing the challenging urban environment. Adequate institutions and financial resources coupled with effective cooperation and coordination among concerned organizations could ameliorate the urban environment as urban community forestry. 相似文献
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A. Chatterjee N. Cattanach R. Awale R. Thapa 《Communications in Soil Science and Plant Analysis》2016,47(4):527-532
Application of nitrification inhibitor has potential to increase soil nitrogen (N) retention throughout the growing season and finally increase corn (Zea mays L.) yield. During the 2012–2014 growing seasons, on-farm field trials were conducted to determine the effects of nitrapyrin (Instinct) with two N sources, urea and urea ammonium nitrate, at two rates, 85% and 100% of recommended N, and side-dress on grain yield and soil inorganic N availability in the Red River Valley of the North Dakota. Preplant urea N at 100% recorded the greatest yield in 2 out of 3 years. At late sampling, the greatest soil inorganic N was observed with side-dress urea ammonium nitrate at 100% within 0–30 cm (last 2 years). For spring fertilizer N management, addition of nitrapyrin had no effect on yield and inconsistent effect on soil N availability. Our results suggest that fertilizer N management should be evaluated on a local scale and consider annual variability in weather. 相似文献
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Impacts of resource extraction on forest structure and diversity in Bardia National Park,Nepal 总被引：1，自引：0，他引：1
Repeated biomass harvesting for human livelihood needs can cause significant changes in forest structure, composition and diversity. Such impacts have often been associated with the distance to villages and their size, but the effects of individual villages in relation to their characteristics have been little studied. Focussing on the issues around communities’ impacts on the forest, this research aimed to understand how resource extraction by two Buffer Zone villages in Nepal's Bardia National Park affects forest structure and diversity. Tree density, basal area, diameter at breast height (DBH), species richness, two diversity indices and disturbance indices were recorded in 108 plots in 12 transects, from March till May 2005, within the park along the village boundaries, where resource extraction occurs, and in the core park area which is isolated from human disturbance. Forest subject to resource extraction had a lower density of trees, smaller DBH and lower species richness and diversity. Forest disturbance declined with distance from the villages but the two villages differed widely in their impact on the forest. Resource use was more intensive in Shivapur village and percentage of trees lopped, average lopping intensity and numbers of dung piles were statistically significant. This was mainly due to the lack of access to Buffer Zone community Forest for Shivapur households. Interviews with villagers suggested that there have been changes in species availability compared to 5 years ago. Households also underestimated the impact of their resource extraction, which may prevent them from changing their behaviour to benefit conservation. It is clear that understanding rural communities’ needs, their framing of resource extraction and utilisation, and dependence on forest resources will be very helpful for long term conservation measures. 相似文献
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Mohammad Wali Salari Patrick Obia Ongom Rima Thapa Henry T. Nguyen Tri D. Vuong Katy Martin Rainey 《Plant Breeding》2021,140(1):110-122
The meal value of Soybean for monogastric animals is determined partly by sucrose, raffinose and stachyose. Of these, sucrose is desirable, while raffinose and stachyose are indigestible, causing flatulence and abdominal discomfort. The objective of this study was to identify quantitative trait loci (QTL) controlling seed sucrose, raffinose, and stachyose in a set of 140 SoyNAM (Nested Association Mapping) recombinant inbred lines (RILs), developed from the cross between lines IA3023 and LD02‐4485. A total of 3,038 SNP markers from the Illumina SoyNAM BeadChip SNP were used to map the QTLs for sucrose and the RFOs, raffinose, and stachyose. Significant genotypic differences (p < .001) among RILs were observed for sucrose, raffinose and stachyose contents across years. A 3038 Illumina SoyNAM BeadChip SNPs identified three QTLs for sucrose, one on chromosome 1, explaining 10% variance and two on chromosome 3 each explaining 22%. Raffinose QTL was detected on chromosome 6, explaining 6% variance. The mapped QTLs were novel and spanned regions harbouring candidate genes with roles in plant growth including seed development. 相似文献
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Amidst the growing concern about agricultural underdevelopment in developing countries, this study addresses the causes and trends of land fragmentation. It analyses the impact of land fragmentation on input use efficiency, crop yield and production efficiency, especially with reference to a mountain district in Nepal. Necessary information was obtained from discussions with groups and individual land users and a questionnaire survey covering 184 households representing different degrees of land fragmentation. The analyses focused on two staple crops, namely, maize and paddy. The analysis revealed an increasing trend in the number of land parcels and a decreasing trend in the size of land parcels, primarily due to the heredity tradition of equal division of land among the inheritors. Other factors such as land purchase have also contributed to land fragmentation. Yield analysis revealed that small parcels are more productive than large parcels, because of higher applications of inputs. Consistent with this, small parcels also appeared to have a higher production efficiency than large parcels—considering both benefit and cost of purchased inputs—indicating a positive impact of land fragmentation on farmers' income. However, an analysis considering also the cost of inputs produced on the farm revealed an opposite trend, that is, on large land parcels, production is more efficient than on small parcels. In view of the need to also recover the cost of the inputs produced on‐farm, it is concluded that land fragmentation—leading to small plots—has a negative impact on production efficiency, thereby constraining agricultural development. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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Background : Since recently, the traditional rice–wheat rotation systems in Nepal are subject to drastic changes. Progressing urbanisation and shifting consumer preferences drive a replacement of wheat by high‐value vegetables during the cold dry season, particularly in the peri‐urban fringes, while emerging water shortages prevent permanent soil flooding during the monsoon season, leading to partial substitution of lowland rice by less water‐consuming upland crops. Associated changes in soil aeration status affect soil nutrient availability while particularly vegetables enhance the demand for the critically limiting micronutrients boron (B) and zinc (Zn). Aim : In both rice‐ (anaerobic) and maize‐based (aerobic) systems we assessed the differential response of traditional winter wheat in comparison to cauliflower and tomato to applied B and Zn fertilizers. Methods : Experiments were conducted (1) in a pot trial with two contrasting soil types (Acrisol vs. Fluvisol) and (2) in field validation trials at two contrasting sites (representing lowland vs. mid‐hills) in Nepal. Results : The on‐going shift from flooded rice to aerobic maize during the wet season negatively affected dry matter accumulation and grain yield of the dry season wheat, but not of cauliflower and tomato. While Zn application tended to increase wheat yields under field conditions, B application induced no significant effect, irrespective of the soil or production site. However, low to moderate applications of B (2.0–4.4 kg ha?1) and Zn (3.3–4.4 kg ha?1) nearly doubled biomass accumulation and nutrient uptake of vegetables and increased the economic yields of cauliflower and tomato between 8 and > 100%. These responses were generally more pronounced in the Fluvisol than the Acrisol. While overall yields of wheat and temperate vegetables were higher in the cool mid‐hills the relative yield responses to applied B were more pronounced in the lowland than the mid‐hill sites. On average, the partial factor productivities of applied fertilizer were low to moderate in wheat, with 1 and 8 € increase in net revenue per € of investment in B and Zn, respectively. In the vegetables, this partial factor productivity increased to about 4 € €?1 investment with Zn, and reached about 43 € €?1 investment in B, irrespective of the production site. Conclusions : While the application of Zn fertilizers can moderately improve the performance of traditional rice–wheat rotations, B and to a lesser extent Zn application become essential and highly profitable when shifting towards vegetable cropping. The demand for B and Zn fertilizers is foreseen to dramatically increase with progressing urbanisation and the associated shifts in production systems of Nepal. 相似文献
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We studied variations in water relations and drought response in five Himalayan tree species (Schima wallichii (DC.) Korth. (chilaune) and Castanopsis indica (Roxb.) Miq. (dhale katus) at an elevation of 1400 m, Quercus lanata Smith (banjh) and Rhododendron arboreum Smith (lali gurans) at 2020 m, and Quercus semecarpifolia Smith (khasru) at 2130 m) at Phulchowki Hill, Kathmandu, Nepal. Soil water potential at 15 (Psi(s15)) and 30 cm (Psi(s30)) depths, tree water potential at predawn (Psi(pd)) and midday (Psi(md)), and leaf conductance during the morning (g(wAM)) and afternoon (g(wPM)) were observed from December 1998 to April 2001, except during the monsoon months. There was significant variation among sites, species and months in Psi(pd), Psi(md), g(wAM) and g(wPM), and among months for all species for Psi(s15). Mean Psi(pd) and Psi(md) were lowest in Q. semecarpifolia (-0.40 and -1.18 MPa, respectively) and highest in S. wallichii (-0.20 and -0.63 MPa, respectively). The minimum Psi value for all species (-0.70 to -1.79 MPa) was observed in March 1999, after 4 months of unusually low rainfall. Some patterns of Psi(pd) were related to phenology and leaf damage. During leafing, Psi(pd) often increased. Mean g(wAM) and g(wPM) were highest in Q. semecarpifolia (172 and 190 mmol m(-2) s(-1), respectively) and lowest in C. indica (78 and 74 mmol m(-2) s(-1), respectively). Soil water potential (Psi) at 15 cm depth correlated with plant Psi in all species, but rarely with g(wAM) and not with g(wPM). Plant Psi declined with increasing elevation, whereas g(w) increased. As Psi(pd) declined, so did maximal g(w), but overall, g(w) was correlated with Psi(pd) only for R. arboreum. Schima wallichii maintained high Psi, with low stomatal conductance, as did Castanopsis indica, except that C. indica had low Psi during dry months. Rhododendron arboreum maintained high Psi(pd) and g(w), despite low soil Psi. Quercus lanata had low g(w) and low Psi(pd) in some months, but showed no correlation between tree Psi and g(w). Quercus semecarpifolia, which grows at the highest elevation, had low soil and plant Psi and high g(w). 相似文献
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