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ArticleJournal articleCharacteristics and dynamics of arbuscular mycorrhizal fungal communities along a chronosequence of teak (Tectona grandis) plantations in Mt. Jianfengling, Hainan Island, China
XV World Forestry Congress, 2-6 May 2022
2022Also available in:
No results found.Teak (Tectona grandis L.f.) is one of the most promising timber species in the tropical and subtropical areas in south China. Arbuscular mycorrhizal (AM) fungi play a crucial role in promoting plant growth, enhancing plant stress resistance and sustaining healthy ecosystem. However, little is known about mycorrhizal status in teak plantations. This study aims to characterize the dynamics of AM fungal communities in the rhizosphere of teak plantations at different ages. Fine roots and rhizosphere soils in teak plantations at varying ages (22, 35, 45 and 55 years old), and the adjacent native grassland without teak plantation (CK) were assessed for soil properties, and AM fungal communities using amplicon sequencing technology. With the increase of stand ages, catalase and ammonium nitrogen in the rhizosphere soil were also increased; soil organic carbon, total phosphorous (P), acid phosphatase, available potassium (AK) and available phosphorus (AP) were first increased and then declined at 55-year-old stand. In total, 12 and 9 AM fungal genera were detected in the rhizosphere soil and in teak root samples, respectively. The OTUs data revealed that AM fungi presented in the rhizosphere soil and roots were mostly belonged to Glomus. In the rhizosphere soil, the relative abundance of Glomus was first increased and then declined, while Gigaspora and Scutellospora were declined, although the diversity and richness of AM fungi showed no significant variation with stand ages. In roots, the composition of AM fungal community and its diversity did not change with stand ages, whereas the richness was increased with the stand age. The monte carlo permutation test indicated that AK, nitrate nitrogen and C/P ratio largely explained the shift in the composition of AM fungal community in the rhizosphere soil. The results demonstrated that AM fungal communities in the rhizosphere soil and teak roots shifted across plantation ages. These changes were largely attributed to the age-induced variation in soil properties. Keywords: Tectona grandis; arbuscular mycorrhizal fungi; stand age; soil properties; plantations ID: 3623633 -
ArticleJournal articleDeveloping simultaneously modeling systems for improving the reliability of tree aboveground biomass- carbon and its components estimates for Machilus odoratissimus nees in the central highlands, Viet Nam
XV World Forestry Congress, 2-6 May 2022
2022Also available in:
No results found.Machilus odoratissimus Nees is a multi-purpose species with, high economic value and environmental protection, so this tree species is commonly used in agroforestry models. In plantation management, it demands modeling systems that predict accurately aboveground biomass- carbon and its components. At the same time, the developed models support computing carbon accumulation of forest trees in agroforestry models for the program of reducing emissions from deforestation and forest degradation (REDD). Twenty-two 300 m2 plots were measured within the full range of 1 to 7 ages in the Central Highlands of VietNam. A total of 22 quadratic mean diameter trees were destructively sampled to obtain a dataset of the dry iomass/carbon of the stem (Bst/Cst), bark (Bba/Cba), branches (Bbr/Cbr), leaves (Ble/Cle), and total tree aboveground biomass/carbon (AGB/AGC). We examined the performance of weighted nonlinear models fit by maximum likelihood and weighted nonlinear seemingly unrelated regression (SUR) fit by generalized least squares for predicting tree aboveground biomass- carbon and its components. The simultaneous estimation of AGB/AGC and its components produced a higher reliability than that of the models of tree components and the total developed separately. The selected forms of modeling systems were AGB = Bst + Bba + Bbr + Ble = a1×(D2H)b1 + a2×(D2H)b2 + a3×Db3 + a4×(D2H)b4 and AGC = Cst + Cba+ Cbr + Cle = a1×(D2H)b1 ++2×(D2H)b2 + a3×Db3 + a4×(D2H)b4 (where D is the diameter at breast height and H is the height of the tree). Keywords: Agroforestry, Machilus odoratissimus, seemingly unrelated regression (SUR), tree biomass- carbon ID: 3472953 -
DocumentOther documentStudy on Chinese herders’ preference for grassland ecological compensation and its impact factors — Based on the survey of two counties in Qinghai Province
XV World Forestry Congress, 2-6 May 2022
2022Also available in:
No results found.China's Grassland covers an area of 390 million hectares, accounting for more than 40% of the total land area. It is the largest terrestrial ecosystem in China. After the institutional reform of the State Council, the State Forestry and Grassland Administration (NFGA) became the department in charge of grassland and forest. NFGA began to explore the long-term mechanism for Grassland Ecological Compensation (GEC). Qinghai Province is the main pastoral region in China, and it is also the water source of Yangtze River, Yellow River and Lantsang River (Mekong River), where there are different herders with different Religious Belief and Minority. It is of great significance for the formulation of long-term GEC mechanism and the implementation of precise policies to study the local herders’ preference for GEC and its influencing factors. Based on 340 questionnaires from Qilian County and Menyuan County in Qinghai Province, this study selects three compensation methods, fund compensation (FC), policy compensation (PC) and substantial compensation (SC), as dependent variables, and takes demographic characteristics, family characteristics, grassland characteristics, policy cognition and other factors as independent variables. Disordered Multiple Logistic Regression Analysis was used in this study. The results show that 69.71% of respondents prefer FC, 20.29% prefer PC, and 10% prefer MC. The impact of some independent variable involved county, demographic characteristics, Family characteristics, grassland characteristics on herders’ preference for GEC means is significant. It is found that policy cognition has no significant to the preference. Therefore, the study believes that FC is still the main compensation method for a period of time, but it should be more diversified and detailed for different groups and their demands in the sustainable compensation mechanism and policy design. Keywords: Agriculture, Governance, Policies, Research ID: 3486732
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Book (stand-alone)Technical bookThe future of food and agriculture - Trends and challenges 2017
Also available in:
No results found.What will be needed to realize the vision of a world free from hunger and malnutrition? After shedding light on the nature of the challenges that agriculture and food systems are facing now and throughout the 21st century, the study provides insights into what is at stake and what needs to be done. “Business as usual” is not an option. Major transformations in agricultural systems, rural economies, and natural resources management are necessary. The present study was undertaken for the quadrennial review of FAO’s strategic framework and for the preparation of the Organization Medium-Term plan 2018-2021. -
BookletCorporate general interestEmissions due to agriculture
Global, regional and country trends 2000–2018
2021Also available in:
No results found.The FAOSTAT emissions database is composed of several data domains covering the categories of the IPCC Agriculture, Forestry and Other Land Use (AFOLU) sector of the national GHG inventory. Energy use in agriculture is additionally included as relevant to emissions from agriculture as an economic production sector under the ISIC A statistical classification, though recognizing that, in terms of IPCC, they are instead part of the Energy sector of the national GHG inventory. FAO emissions estimates are available over the period 1961–2018 for agriculture production processes from crop and livestock activities. Land use emissions and removals are generally available only for the period 1990–2019. This analytical brief focuses on overall trends over the period 2000–2018. -
Book (series)FlagshipThe State of Food Security and Nutrition in the World 2021
Transforming food systems for food security, improved nutrition and affordable healthy diets for all
2021In recent years, several major drivers have put the world off track to ending world hunger and malnutrition in all its forms by 2030. The challenges have grown with the COVID-19 pandemic and related containment measures. This report presents the first global assessment of food insecurity and malnutrition for 2020 and offers some indication of what hunger might look like by 2030 in a scenario further complicated by the enduring effects of the COVID-19 pandemic. It also includes new estimates of the cost and affordability of healthy diets, which provide an important link between the food security and nutrition indicators and the analysis of their trends. Altogether, the report highlights the need for a deeper reflection on how to better address the global food security and nutrition situation.To understand how hunger and malnutrition have reached these critical levels, this report draws on the analyses of the past four editions, which have produced a vast, evidence-based body of knowledge of the major drivers behind the recent changes in food security and nutrition. These drivers, which are increasing in frequency and intensity, include conflicts, climate variability and extremes, and economic slowdowns and downturns – all exacerbated by the underlying causes of poverty and very high and persistent levels of inequality. In addition, millions of people around the world suffer from food insecurity and different forms of malnutrition because they cannot afford the cost of healthy diets. From a synthesized understanding of this knowledge, updates and additional analyses are generated to create a holistic view of the combined effects of these drivers, both on each other and on food systems, and how they negatively affect food security and nutrition around the world.In turn, the evidence informs an in-depth look at how to move from silo solutions to integrated food systems solutions. In this regard, the report proposes transformative pathways that specifically address the challenges posed by the major drivers, also highlighting the types of policy and investment portfolios required to transform food systems for food security, improved nutrition, and affordable healthy diets for all. The report observes that, while the pandemic has caused major setbacks, there is much to be learned from the vulnerabilities and inequalities it has laid bare. If taken to heart, these new insights and wisdom can help get the world back on track towards the goal of ending hunger, food insecurity, and malnutrition in all its forms.