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81.
Muhammad Sajid Muhammad Ali Khan Wasim Bilal Abdur Rab Zafar Iqbal Sana Irshad khan 《Gesunde Pflanzen》2017,69(3):113-121
Peach fruit is enriched with natural antioxidants but oxidation caused by biotic and abiotic stresses, reduce these antioxidants and consequently effect the quality and yield of the fruit. Therefore, an experiment was conducted to investigate the role of ascorbic acid to sustain the natural antioxidant activity, improve the fruit quality and yield of peach cultivars (Early Grand and Florida King). The peach cultivars, Early Grand and Florida King were tested against four levels of ascorbic acid (200, 400, 600 and 800?ppm) and compared with control as water spray. The foliar application of ascorbic acid significantly influenced anti-oxidant activity and physico-chemical attributes of peach cultivars. However, the foliar application of ascorbic acid @ 800?ppm significantly increased the fruit weight, fruit yield, fruit firmness, total soluble solids, titratable acidity, antioxidant activity of fruit peel, with least percent infected fruits and fruit juice pH as compared to the rest of the treatments. Similarly, significant variation was recorded for peach cultivars regarding anti-oxidant activity and various physico-chemical attributes. The maximum fruit weight, fruit yield, fruit firmness, total soluble solids, titratable acidity and TSS/TA ratio were noted in fruit of cultivar Florida King. On other side the foliar treated fruit of peach cultivar Early Grand had the highest percent infected fruits, fruit juice pH and antioxidant activity of fruit peel. It is concluded from the significant findings of present research that the peach cultivar Florida King performed better in terms of maximum fruit yield, whereas the cultivar Early Grand produced better quality fruits with high anti-oxidant activity when treated with 800?ppm of ascorbic acid as foliar spray. 相似文献
82.
Previous work in the agri-food tradition has framed food auditing as a novelty characteristic of a shift to neoliberal governance in agri-food systems and has tackled the analysis of food “quality” in the same light. This article argues that agri-food scholars’ recent interest in the contested qualities of food needs to be situated alongside a much longer history of contested cultural attributions of trust in food relations. It builds on an earlier discussion suggesting that, although neoliberalism has undoubtedly opened up new spaces for audit activity, older political and social dynamics operating around food audits were established long before the neoliberal historical moment. Breaking new ground (as far as is known) by looking further back than the early history of the organic social movement, it examines intersections of religious food auditing, migrant food culture, and commercial dynamics in food systems. Based on secondary sources, two contrasting case studies are presented to illustrate the flux and complexity for: New World Diaspora migrants to New York City of assuring food was kosher; and more recent Maghrebi migrants to southwest France of assuring food is halal. The article concludes by noting that the neoliberal moment stands not as the unique progenitor of a new style of food authority, but rather as the latest response to a wider rupture in the historically contingent arbitration of new forms of trust in food. 相似文献
83.
Parklands are mixtures of trees and shrubs that farmers select for certain functions. In the Sahel, parklands are cultivated
together with staple food crops, such as millet and sorghum. Parkland trees are sources of foods, including fruits, fats,
oils, leafy vegetables, nuts and condiments that complement food crops in the local diet. Despite their socio-economic and
ecological role, many studies have shown that the parklands are degrading very rapidly. Therefore, there is a need to undertake
restoration actions that are based on a clear understanding of the livelihood context, such as the wealth status of the farmers,
in which these agroecosystems are evolving. Thus, we conducted a wealth survey with rural communities in two different farming
systems of Burkina Faso that are the cereal-based system in the “Plateau Central” and the cotton-based system in the “Boucle
du Mouhoun”. A total of twelve villages were sampled, six villages for each system. The Participatory Analysis of Poverty
and Livelihood Dynamics (PAPoLD) method was used by rural farmers to rank farmer households of their communities according
to their wealth status. The results revealed that 70% of households in the Plateau Central and 56% in the “Boucle du Mouhoun”
managed to escape poverty, and became wealthy. However, 2% of households of the villages in the Plateau Central and 6% in
“Boucle du Mouhoun” fell into poverty in the same period whereas 9 and 12% remained poor in these zones, respectively. The
main causes associated with households getting out of poverty are subsidies for cotton, external revenues from relatives working
in towns and gardening activities. Death of spouse, illness, high number of people in the household and indebtedness are the
main causes that lead into poverty. The implications of these findings in designing appropriate policies and management options
for a sustainable management of agroforestry parklands under different land use systems were finally discussed. 相似文献
84.
85.
Kinh Bac Dang Benjamin Burkhard Felix Müller Van Bao Dang 《Paddy and Water Environment》2018,16(4):767-781
Land use change due to the development of agriculture and community-based tourism has resulted in an increase in natural hazards (e.g. erosion and landslides) that affect sustainability in the Sapa mountainous area in northern Vietnam. Natural hazard regulating ecosystem services have protected the local people from the destruction of their villages, goods and natural resources, especially in the rainy season. However, it is difficult to identify which kinds of anthropogenic constructions support a co-production of regulating services in human-influenced social–ecological systems and in which specific types of land use and land cover the supply of such services takes place, especially in heterogeneous mountainous areas. Therefore, this research attempts to (1) distinguish between the potential and actual use (flow) of natural hazard regulating ecosystem services and (2) understand how soil erosion and landslide regulating ecosystem services can contribute to a sustainable management of different ecosystems, especially in rice fields and forest areas. Two models (InVEST for soil erosion, Analytic Hierarchy Process for landslide analysis) were used to analyze and map the contributions of natural versus anthropogenic components for regulating natural hazards in Sapa. The results show the incoherent distribution of erosion regulating services and low capacities of landslide regulating services in areas that have seriously been affected by human activities, especially forestry and agricultural development. The contribution of rice ecosystems to soil erosion mitigation is higher than in the case of landslides. Nevertheless, one-third of the area of paddy fields in the case study area have “no” capacity to supply natural hazard regulating ecosystem services and should therefore be re-forested. 相似文献
86.
Xenia K. Volk Johannes P. Gattringer Annette Otte Sarah Harvolk-Schöning 《Landscape Ecology》2018,33(3):371-387
Context
Methods for measuring restoration success that include functional connectivity between species’ populations are rare in landscape ecology and restoration practices. We developed an approach that analyzes connectivity between populations of target species and their dispersal probabilities to assess restoration success based on easily accessible input data. Applying this method to landscape development scenarios can help optimize restoration planning.Objectives
We developed an assessment for restoration success and restoration planning based on functional connectivity between species’ populations and spatially explicit scenarios. The method was used in a case study to test its applicability.Methods
Based on data on available habitat, species’ occurrence and dispersal ranges, connectivity metrics and dispersal probabilities for target species are calculated using the software Conefor Sensinode. The metrics are calculated for scenarios that reflect possible changes in the landscape to provide a basis for future restoration planning. We applied this approach to floodplain meadows along the Upper Rhine for four plant species and three future scenarios.Results
In the case study, habitats of the target species were poorly connected. Peucedanum officinale and Sanguisorba officinalis were more successful in recolonizing new habitats than Iris spuria and Serratula tinctoria. The scenarios showed that restoration of species-rich grassland was beneficial for dispersal of the target species. As expected in the agriculturally dominated study area, restoration of former arable land significantly increased dispersal probabilities.Conclusions
In the case study, the developed approach was easily applicable and provided reasonable results. Its implementation will be helpful in decision-making for future restoration planning.87.
A number of improved cultivars of food legume crops have been developed and released in the tropics and the sub-tropics. Most
of these cultivars have been developed through conventional breeding approaches based on the development of crop varieties
under optimum soil fertility levels. Nevertheless, it is hardly possible to say that the varietal provisions made by the past
approach have been readily accepted, and properly utilized to boost productivity of food legumes grown by resource-poor farmers.
The approach itself did not fully appreciate the actual circumstances of the resource-poor farmers where marginal production
systems prevail and the poorest farmers could not afford to use cultivars developed under optimum soil fertility level. Therefore,
the limitations and strategic implications of past experiences made to develop crop cultivars need to be analyzed in order
to formulate better strategies and approaches in the future. The main purpose of this article is to review the efforts made,
the technical difficulties associated with the genetic improvement in food legumes as related to plant-nutrient relations,
causes of limited breeding success and thereby draw lessons useful to designing future breeding strategies. The scope of nutrient
deficiency stress and the approaches to breeding for plant-nutrient relations are discussed and the need for refining the
approach and better targeting of the breeding methodologies suggested. 相似文献
88.
In the United States, food banks served an estimated 46 million people in 2015. A combination of government policy reforms and political economic trends contributed to the rising numbers of individuals relying on private food assistance in the US, the United Kingdom and other high-income countries. Although researchers frequently map urban food environments, this project is one of the first to map private food assistance and potential need at the census-tract scale. We utilize Geographic Information Systems, demographic data, and food assistance locations to develop a rapid assessment tool that could support food banks, pantries, soup kitchens, and government agencies that seek to answer the question of whether people with the greatest need have food distribution sites in close proximity. We define access based on distance and then calculate potential food insecurity using either poverty rates or a food insecurity index. We apply these methods in a case study analysis of Santa Clara County, California. Our findings suggest that food assistance distribution locations match the areas of potential need in more than 80% of urban census tracts. However, there are several potentially underserved locations and populations that could benefit from new food assistance operations. The poverty and index-based approaches show significant spatial overlap in mapped areas of high food insecurity and low access. The poverty only approach produces a higher estimate of food insecurity rates, is easier to calculate, and draws attention to the need to address poverty as a root cause of hunger. 相似文献
89.
This article analyses motivations and attitudes of small-scale forest owners in the Czech Republic towards joining associations. The research is a follow-up to a field investigation performed within the National Forest Programme II for 2007–2013 in the Vyso?ina region in 2010. The present research was carried out in the Pilsen region in 2012 and the Central Bohemia region in 2015, applying the same method of investigation as in 2010—a questionnaire survey. The findings are based on the results of all three surveys and supported by the analysis of legal and forestry-related documents concerning financial subsidies for forest owners’ associations. The study has revealed reluctance of small-scale owners to join associations. Their lack of motivation is caused by insufficient funding from the government supporting the administration and management of associations. The reluctance also results from the request for associations to be legal entities, which most applicants do not meet as they are either not registered or are registered under unsuitable legal forms. Between 2011 and 2013, no contributions were paid by the government to associations, and no new small-scale forest owners’ associations were formed. To increase associations, we propose that the government should provide sufficient funding not only for the administration and management of associations but also for the process of establishing associations and initial investments. It is also necessary to make major innovations in legislature regarding the transition of ownerships to more convenient legal forms. 相似文献
90.
Weizhen Wang Linan He Zhuzhu Zhang Wenzhi Li Jia Chen Tingting Chen Youhua Long 《Pest management science》2023,79(7):2493-2502