Yazar "Ahmad, Ashfaq" seçeneğine göre listele

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    Evaluating the efficiency of coarser to finer resolution multispectral satellites in mapping paddy rice fields using GEE implementation
    (Nature Portfolio, 2022) Waleed, Mirza; Mubeen, Muhammad; Ahmad, Ashfaq; Habib-ur-Rahman, Muhammad; Amin, Asad; Farid, Hafiz Umar; Hussain, Sajjad
    Timely and accurate estimation of rice-growing areas and forecasting of production can provide crucial information for governments, planners, and decision-makers in formulating policies. While there exists studies focusing on paddy rice mapping, only few have compared multi-scale datasets performance in rice classification. Furthermore, rice mapping of large geographical areas with sufficient accuracy for planning purposes has been a challenge in Pakistan, but recent advancements in Google Earth Engine make it possible to analyze spatial and temporal variations within these areas. The study was carried out over southern Punjab (Pakistan)-a region with 380,400 hectares devoted to rice production in year 2020. Previous studies support the individual capabilities of Sentinel-2, Landsat-8, and Moderate Resolution Imaging Spectroradiometer (MODIS) for paddy rice classification. However, to our knowledge, no study has compared the efficiencies of these three datasets in rice crop classification. Thus, this study primarily focuses on comparing these satellites' data by estimating their potential in rice crop classification using accuracy assessment methods and area estimation. The overall accuracies were found to be 96% for Sentinel-2, 91.7% for Landsat-8, and 82.6% for MODIS. The F1-Scores for derived rice class were 83.8%, 75.5%, and 65.5% for Sentinel-2, Landsat-8, and MODIS, respectively. The rice estimated area corresponded relatively well with the crop statistics report provided by the Department of Agriculture, Punjab, with a mean percentage difference of less than 20% for Sentinel-2 and MODIS and 33% for Landsat-8. The outcomes of this study highlight three points; (a) Rice mapping accuracy improves with increase in spatial resolution, (b) Sentinel-2 efficiently differentiated individual farm level paddy fields while Landsat-8 was not able to do so, and lastly (c) Increase in rice cultivated area was observed using satellite images compared to the government provided statistics.
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    Impact of climate change on agricultural production; Issues, challenges, and opportunities in Asia
    (Frontiers Media Sa, 2022) Habib-ur-Rahman, Muhammad; Ahmad, Ashfaq; Raza, Ahsan; Hasnain, Muhammad Usama; Alharby, Hesham F.; Alzahrani, Yahya M.; Bamagoos, Atif A.
    Agricultural production is under threat due to climate change in food insecure regions, especially in Asian countries. Various climate-driven extremes, i.e., drought, heat waves, erratic and intense rainfall patterns, storms, floods, and emerging insect pests have adversely affected the livelihood of the farmers. Future climatic predictions showed a significant increase in temperature, and erratic rainfall with higher intensity while variability exists in climatic patterns for climate extremes prediction. For mid-century (2040-2069), it is projected that there will be a rise of 2.8 degrees C in maximum temperature and a 2.2 degrees C in minimum temperature in Pakistan. To respond to the adverse effects of climate change scenarios, there is a need to optimize the climate-smart and resilient agricultural practices and technology for sustainable productivity. Therefore, a case study was carried out to quantify climate change effects on rice and wheat crops and to develop adaptation strategies for the rice-wheat cropping system during the mid-century (2040-2069) as these two crops have significant contributions to food production. For the quantification of adverse impacts of climate change in farmer fields, a multidisciplinary approach consisted of five climate models (GCMs), two crop models (DSSAT and APSIM) and an economic model [Trade-off Analysis, Minimum Data Model Approach (TOAMD)] was used in this case study. DSSAT predicted that there would be a yield reduction of 15.2% in rice and 14.1% in wheat and APSIM showed that there would be a yield reduction of 17.2% in rice and 12% in wheat. Adaptation technology, by modification in crop management like sowing time and density, nitrogen, and irrigation application have the potential to enhance the overall productivity and profitability of the rice-wheat cropping system under climate change scenarios. Moreover, this paper reviews current literature regarding adverse climate change impacts on agricultural productivity, associated main issues, challenges, and opportunities for sustainable productivity of agriculture to ensure food security in Asia. Flowing opportunities such as altering sowing time and planting density of crops, crop rotation with legumes, agroforestry, mixed livestock systems, climate resilient plants, livestock and fish breeds, farming of monogastric livestock, early warning systems and decision support systems, carbon sequestration, climate, water, energy, and soil smart technologies, and promotion of biodiversity have the potential to reduce the negative effects of climate change.
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    Managing Greenhouse Gas Emission
    (wiley, 2022) Hussain, Sajjad; Mubeen, Muhammad; Sultana, Syeda Refat; Ahmad, Ashfaq; Fahad, Shah; Nasim, Wajid; Ahmad, Shakeel
    Rice (Oryza sativa) production systems have faced the two opposing challenges all over the world: the need to increase the production to nourish the world’s increasing population and reducing the emissions of greenhouse gases (GHG). Nitrous oxide (N2O), carbon dioxide (CO2), methane (CH4), and chlorofluorocarbons (CFCs) are the most significant GHGs because of their global warming mitigation (GWM) and radiative effects on rice. Rice intensive farming system has been producing extreme pressure on fields of rice for producing more rice for the increasing global population, thus declining rice ecosystem balance and soil fertility situation by fluxes of more N2O, CH4, and CO2 to the environment. Many farmers used fertilizer combination and commercial hormone to rice growing. Nowadays, the integrated management system like modifying tillage practices, improving nitrogen fertilization and irrigation patterns, increasing yield potential, and managing organic and fertilizer inputs are set up based on plant physiological needs. These strategies can also increase the yield of rice as well as have benefits on GWM. Satellite-based estimates provide unique opportunities to improve bottom-up and top-down estimate of GHG emissions, and also provide important observations to support the understanding as well as monitoring of environment and earth’s surface changes due to human activities. The integrated management system, an eco-farming method, gives the best solution than transgenic plants (in which several problems including field tests and stability of the transgenic lines are inevitable). Adapting drainage systems could be a good option for reducing CH4 in rice production system. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2022.
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    World nations priorities on climate change and food security
    (Springer International Publishing, 2021) Ul Din, Muhammad Sami; Mubeen, Muhammad; Hussain, Sajjad; Ahmad, Ashfaq; Hussain, Nazim; Ali, Muhammad Anjum; Sabagh, Ayman El
    The present food system (including production, transportation, processing, packaging, storing, retail, and consumption) is a source of nutrition for the great majority of the world population in addition to supporting the livelihoods of about 200 million people. Food supply per capita has increased by more than 30% since 1961, this is accompanied by more use of nitrogen fertilizers (showing an increase of about 800%) and water resources for irrigation (with an increase of more than 100%). Global food security will continue to be an international concern for the coming 50 years and even beyond. Crop yield has fallen in many areas recently due to decreasing investments in infrastructure and research, as well as due to growing water scarcity. Climate change is a global concern irrespective of borders. The poor nations are highly vulnerable to climate change and are at high risk. Food security is directly dependant on the food chain and the associated food system process. All dimensions of food security could be affected by climate change in complex ways. Approximately, 15 countries are highly vulnerable to food insecurity due to climate change, from Asia and Africa. Most of these nations are not able to cope with or counter the impact of climate change on an urgent basis. However, some countries have developed their national strategies and adaptation plans to alleviate the negative impacts of climate change. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2022.