Marcelo Rezende

Bio: Marcelo Rezende is an academic researcher from Food and Agriculture Organization. The author has contributed to research in topics: Population & Tree (data structure). The author has an hindex of 5, co-authored 8 publications receiving 964 citations. Previous affiliations of Marcelo Rezende include Universidade Federal de Minas Gerais & Sapienza University of Rome.

The global tree restoration potential.

Abstract: The restoration of trees remains among the most effective strategies for climate change mitigation. We mapped the global potential tree coverage to show that 4.4 billion hectares of canopy cover could exist under the current climate. Excluding existing trees and agricultural and urban areas, we found that there is room for an extra 0.9 billion hectares of canopy cover, which could store 205 gigatonnes of carbon in areas that would naturally support woodlands and forests. This highlights global tree restoration as our most effective climate change solution to date. However, climate change will alter this potential tree coverage. We estimate that if we cannot deviate from the current trajectory, the global potential canopy cover may shrink by ~223 million hectares by 2050, with the vast majority of losses occurring in the tropics. Our results highlight the opportunity of climate change mitigation through global tree restoration but also the urgent need for action.

The extent of forest in dryland biomes

Abstract: Dryland biomes cover two-fifths of Earth’s land surface, but their forest area is poorly known. Here, we report an estimate of global forest extent in dryland biomes, based on analyzing more than 210,000 0.5-hectare sample plots through a photo-interpretation approach using large databases of satellite imagery at (i) very high spatial resolution and (ii) very high temporal resolution, which are available through the Google Earth platform. We show that in 2015, 1327 million hectares of drylands had more than 10% tree-cover, and 1079 million hectares comprised forest. Our estimate is 40 to 47% higher than previous estimates, corresponding to 467 million hectares of forest that have never been reported before. This increases current estimates of global forest cover by at least 9%.

Collect Earth: Land Use and Land Cover Assessment through Augmented Visual Interpretation

Abstract: Collect Earth is a free and open source software for land monitoring developed by the Food and Agriculture Organization of the United Nations (FAO). Built on Google desktop and cloud computing technologies, Collect Earth facilitates access to multiple freely available archives of satellite imagery, including archives with very high spatial resolution imagery (Google Earth, Bing Maps) and those with very high temporal resolution imagery (e.g., Google Earth Engine, Google Earth Engine Code Editor). Collectively, these archives offer free access to an unparalleled amount of information on current and past land dynamics for any location in the world. Collect Earth draws upon these archives and the synergies of imagery of multiple resolutions to enable an innovative method for land monitoring that we present here: augmented visual interpretation. In this study, we provide a full overview of Collect Earth’s structure and functionality, and we present the methodology used to undertake land monitoring through augmented visual interpretation. To illustrate the application of the tool and its customization potential, an example of land monitoring in Papua New Guinea (PNG) is presented. The PNG example demonstrates that Collect Earth is a comprehensive and user-friendly tool for land monitoring and that it has the potential to be used to assess land use, land use change, natural disasters, sustainable management of scarce resources and ecosystem functioning. By enabling non-remote sensing experts to assess more than 100 sites per day, we believe that Collect Earth can be used to rapidly and sustainably build capacity for land monitoring and to substantively improve our collective understanding of the world’s land use and land cover.

Response to Comments on “The global tree restoration potential”

Abstract: Our study quantified the global tree restoration potential and its associated carbon storage potential under existing climate conditions. We received multiple technical comments, both supporting and disputing our findings. We recognize that several issues raised in these comments are worthy of discussion. We therefore provide a detailed common answer where we show that our original estimations are accurate.

Environmental factors and human activity as drivers of tree cover and density on the Island of Socotra, Yemen

Abstract: Socotra Island, in the western Indian Ocean, harbors high biodiversity and endemism and makes up the largest part of the Socotra archipelago UNESCO World Heritage site Its climatic, pedological, and geomorphological characteristics, together with the long geological isolation and inaccessibility, led to the flourishing of unique tree diversity, with great cultural and ecological value Lately, trees on Socotra are facing new threats linked to the abandonment of traditional management practices, climate change impacts, and growing human pressure This study assesses the relative influence of environmental factors and human activity as drivers of tree cover and density, which can be used to support land management policies for the conservation of this key local resource Tree cover and density were assessed on a total of 3600 plots of 05 ha each, laid on a regular grid covering the entire area of the island through Collect Earth, a free open source software tool that allows an augmented visual interpretation of high-resolution satellite images A total of 770,000 trees, with an average of 214 trees/ha, were estimated on the island The collected data was validated by ground surveys in 26 plots The relative influence of selected predictors (seven environmental, two anthropic) on tree cover and density was analyzed through logistic and survival regression Tree cover and density were found to be impacted positively by steeper slopes, higher rainfall, and marked precipitation seasonality and negatively by relatively warmer temperatures and a higher sand content in the soil Distance of each plot from the nearest road and settlement was calculated and neither of these anthropic predictors emerged as significant, indicating that the limited number of trees present are not currently as affected by anthropic pressure, but, instead, their presence is mostly limited by the harsh climatic and pedological factors However, as human population and development increase, periods of drought rise, and extreme and random climatic events intensify, these additional stresses on the environment could negatively impact the availability of natural resources in the terrestrial environment Lastly, potential recommendations to the existing conservation policies and Socotra Conservation Zoning Plan are discussed based on the results

United Nations Educational, Scientific and Cultural Organization (UNESCO)

Abstract: On behalf of Mr. Koichiro Matsuura, Director-General of UNESCO, it is my great pleasure to welcome you all to this international scientific conference. Drylands are often considered fragile ecosystems, yet they have a remarkable resilience to stress. They are home to unique and well-adapted plant and animal species that we need to conserve. Some of the world’s greatest cultures and belief systems have originated in drylands. On the other hand, desertification and land degradation in drylands often result in poverty and cause environmental refugees to abandon their homes. These problems can only be addressed in a holistic manner, based on sound scientific research and findings. Solutions to the problems of dryland degradation need to be communicated as widely as possible through education at all levels. These are many reasons why UNESCO – within its mandate of science, education, culture and communication – took the intiative to organize this conference. And we are glad that so many partners have responded to our call. UNESCO considers this conference as its main contribution to the observance of the International Year of Deserts and Desertification in 2006. We have deliberately chosen the title ‘The Future of Drylands’ as we feel it is time to redefine our priorities for science, education and governance in the drylands based on 50 years of scientific research in arid and semi-arid zones. In fact UNESCO has one of the longest traditions, within the UN system, of addressing dryland problems from an interdisciplinary, scientific point of view. In 1955, the ‘International Arid Land Meetings’ were held in Socorro, New Mexico (USA). They were organized by the American Association for the Advancement of Science (AAAS), sponsored by UNESCO and supported by the Rockefeller Foundation. One important output of the International Arid Land Meetings was a book entitled The Future of Drylands, edited by Gilbert F. White and published in

The global tree restoration potential.

Abstract: The restoration of trees remains among the most effective strategies for climate change mitigation. We mapped the global potential tree coverage to show that 4.4 billion hectares of canopy cover could exist under the current climate. Excluding existing trees and agricultural and urban areas, we found that there is room for an extra 0.9 billion hectares of canopy cover, which could store 205 gigatonnes of carbon in areas that would naturally support woodlands and forests. This highlights global tree restoration as our most effective climate change solution to date. However, climate change will alter this potential tree coverage. We estimate that if we cannot deviate from the current trajectory, the global potential canopy cover may shrink by ~223 million hectares by 2050, with the vast majority of losses occurring in the tropics. Our results highlight the opportunity of climate change mitigation through global tree restoration but also the urgent need for action.

Pervasive human-driven decline of life on Earth points to the need for transformative change

Abstract: The human impact on life on Earth has increased sharply since the 1970s, driven by the demands of a growing population with rising average per capita income. Nature is currently supplying more materials than ever before, but this has come at the high cost of unprecedented global declines in the extent and integrity of ecosystems, distinctness of local ecological communities, abundance and number of wild species, and the number of local domesticated varieties. Such changes reduce vital benefits that people receive from nature and threaten the quality of life of future generations. Both the benefits of an expanding economy and the costs of reducing nature's benefits are unequally distributed. The fabric of life on which we all depend-nature and its contributions to people-is unravelling rapidly. Despite the severity of the threats and lack of enough progress in tackling them to date, opportunities exist to change future trajectories through transformative action. Such action must begin immediately, however, and address the root economic, social, and technological causes of nature's deterioration.

Characteristics, drivers and feedbacks of global greening

Abstract: Vegetation greenness has been increasing globally since at least 1981, when satellite technology enabled large-scale vegetation monitoring. The greening phenomenon, together with warming, sea-level rise and sea-ice decline, represents highly credible evidence of anthropogenic climate change. In this Review, we examine the detection of the greening signal, its causes and its consequences. Greening is pronounced over intensively farmed or afforested areas, such as in China and India, reflecting human activities. However, strong greening also occurs in biomes with low human footprint, such as the Arctic, where global change drivers play a dominant role. Vegetation models suggest that CO2 fertilization is the main driver of greening on the global scale, with other factors being notable at the regional scale. Modelling indicates that greening could mitigate global warming by increasing the carbon sink on land and altering biogeophysical processes, mainly evaporative cooling. Coupling high temporal and fine spatial resolution remote-sensing observations with ground measurements, increasing sampling in the tropics and Arctic, and modelling Earth systems in more detail will further our insights into the greening of Earth. Vegetation on Earth is increasing, potentially leading to a larger terrestrial carbon sink. In this Review, we discuss the occurrence of this global greening phenomenon, its drivers and how it might impact carbon cycling and land-atmosphere heat and water fluxes.

Food and Agriculture Organization (FAO) ホームページの活用法

Abstract: Food and Agriculture Organization (FAO) The Food and Agriculture Organization (FAO), established in 1945, is a UN specialized agency that provides global data and expertise on agri­ culture and nutrition, fisheries, forestry, and other food and agriculture– related issues. FAO is the UN system’s largest autonomous agency, with headquarters in Rome, 78 country offices and 15 regional, sub–regional, and liaison offices, including one located in Washington, D.C. FAO’s highest policy–making body, the biennial General Conference, comprises all 183 FAO member countries plus the European Commission. The General Conference determines FAO policy and approves FAO’s reg­ ular program of work and budget. The 31st Conference, meeting in November 1999, re–elected Director–General Jacques Diouf (Senegal) to a second six–year term through December 2005. Each biennial Confer­ ence elects a 49–member Council that meets semi–annually to make rec­ ommendations to the General Conference on budget and policy issues. The North America region, which comprises the United States and Can­ ada, is allocated two seats on the Council and one seat each on FAO’s Program, Finance, and Constitutional and Legal Matters (CCLM) Com­ mittees. The United States holds the North American seats on the Finance and Joint Staff Pension Committees through December 2003. Canada holds the North American seat on the CCLM and Program Committees through December 2003. The United States participated at the World Food Summit: Five Years Later meeting held at FAO headquarters June 10–13, 2002, to discuss progress towards attaining the 1996 World Food Summit target of reduc­ ing the world’s number of hungry and malnourished by half by 2015. The United States presented new initiatives to improve agriculture productivity as a significant contribution toward meeting that goal. U.S. Secretary of Agriculture Ann Veneman, leading the U.S. delegation, joined other min­ isters and heads of state and government in adopting a Declaration, “The International Alliance Against Hunger,” which reiterated the goals of the 1996 World Food Summit and stated, inter alia, “we are committed to