Land Degradation Assessment with Earth Observation

This Special Issue (SI) on “Land Degradation Assessment with Earth Observation” comprises 17 original research papers with a focus on land degradation in arid, semiarid and dry-subhumid areas (i.e., desertification) in addition to temperate rangelands, grasslands, woodlands and the humid tropics. The studies cover different spatial, spectral and temporal scales and employ a wealth of different optical and radar sensors. Some studies incorporate time-series analysis techniques that assess the general trend of vegetation or the timing and duration of the reduction in biological productivity caused by land degradation. As anticipated from the latest trend in Earth Observation (EO) literature, some studies utilize the cloud-computing infrastructure of Google Earth Engine to cope with the unprecedented volume of data involved in current methodological approaches. This SI clearly demonstrates the ever-increasing relevance of EO technologies when it comes to assessing and monitoring land degradation. With the recently published IPCC Reports informing us of the severe impacts and risks to terrestrial and freshwater ecosystems and the ecosystem services they provide, the EO scientific community has a clear obligation to increase its efforts to address any remaining gaps—some of which have been identified in this SI—and produce highly accurate and relevant land-degradation assessment and monitoring tools

Desertification

IPCC SPECIAL REPORT ON CLIMATE CHANGE AND LAND (SRCCL) Chapter 3: Climate Change and Land: An IPCC special report on climate change, desertification, land degradation, sustainable land management, food security, and greenhouse gas fluxes in terrestrial ecosystem

Advancing Functional Understanding of Primary Production in Drylands: Insights from a Data-Integration Approach

Dryland ecosystems are highly vulnerable and degradation-prone regions, especially under the premises of global change. Since drylands are preponderantly used as rangelands for livestock production, reliable provision of natural resources and basic ecosystem services, such as forage, are indispensable for local livelihoods. Even though climate projections for drylands still exhibit considerable variation and uncertainty across scenarios and regions, there is a general trend that most dryland regions are facing unbeneficial changes. In particular, climatic aridity and variability are projected to increase even above the already high level of today. Simultaneously, population growth will further increase the demand for ecosystem services from drylands, with negative feedbacks on ecosystem functioning. Given the high natural variability in drylands, as well as future projections, the assessment of drylands’ current and future provision of ecosystem services is challenging, yet essential. The most common estimate for a major ecosystem service of dryland ecosystems (i.e. forage) is aboveground net primary production (ANPP). This cumulative dissertation aimed at advancing our understanding of dryland ecosystems’ functioning and ecosystem service provision, taking a global perspective. Particularly, data integration and standardization techniques were used to derive new insights from available data on drylands’ primary production. With this innovative approach, it could be shown that dryland primary production is mainly driven by precipitation and grazing, not only locally but also on a global scale (Chapter 2.1). Another important outcome was that effects of grazing and rainfall are not merely additive, but could mask each other (Chapter 2.1) or interact in complex ways (Chapter 2.3). Similarly, drought severity may influence primary production either linearly or non-linearly, depending on vegetation characteristics (Chapter 2.3). These findings underline the complex dynamics of dryland ecosystems. Besides these general findings, the established methodological toolbox as well as the assembled global database of dryland primary production are among the main merits of this dissertation. The combination of a large global database, the normalization of ANPP and precipitation data (Chapter 2.2), and the collection of additional site- or study-based information allowed the assessment of ecosystem functioning and stability on a global scale, which thus far could only be done on a theoretical or anecdotal basis

The Glacier Complexes of the Mountain Massifs of the North-West of Inner Asia and their Dynamics

The subject of this paper is the glaciation of the mountain massifs Mongun-Taiga, Tavan-Boghd-Ola, Turgeni- Nuru, and Harhira-Nuru. The glaciation is represented mostly by small forms that sometimes form a single complex of domeshaped peaks. According to the authors, the modern glaciated area of the mountain massifs is 21.2 km2 (Tavan-Boghd-Ola), 20.3 km2 (Mongun-Taiga), 42 km2 (Turgeni- Nuru), and 33.1 km2 (Harhira-Nuru). The area of the glaciers has been shrinking since the mid 1960’s. In 1995–2008, the rate of reduction of the glaciers’ area has grown considerably: valley glaciers were rapidly degrading and splitting; accumulation of morainic material in the lower parts of the glaciers accelerated. Small glaciers transformed into snowfields and rock glaciers. There has been also a degradation of the highest parts of the glaciers and the collapse of the glacial complexes with a single zone of accumulation into isolated from each other glaciers. Reduced snow cover area has led to a rise in the firn line and the disintegration of a common accumulation area of the glacial complex. In the of the Mongun-Taiga massif, in 1995– 2008, the firn line rose by 200–300 m. The reduction of the glaciers significantly lagged behind the change in the position of the accumulation area boundary. In the past two years, there has been a significant recovery of the glaciers that could eventually lead to their slower degradation or stabilization of the glaciers in the study area

Integrated Applications of Geo-Information in Environmental Monitoring

This book focuses on fundamental and applied research on geo-information technology, notably optical and radar remote sensing and algorithm improvements, and their applications in environmental monitoring. This Special Issue presents ten high-quality research papers covering up-to-date research in land cover change and desertification analyses, geo-disaster risk and damage evaluation, mining area restoration assessments, the improvement and development of algorithms, and coastal environmental monitoring and object targeting. The purpose of this Special Issue is to promote exchanges, communications and share the research outcomes of scientists worldwide and to bridge the gap between scientific research and its applications for advancing and improving society

Changing Deserts

Deserts – vast, empty places where time appears to stand still. The very word conjures images of endless seas of sand, blistering heat and a virtual absence of life. However, deserts encompass a large variety of landscapes and life beyond our stereotypes. As well as magnificent Saharan dunes under blazing sun, the desert concept encompasses the intensely cold winters of the Gobi, the snow-covered expanse of Antarctica and the rock-strewn drylands of Pakistan. Deserts are environments in perpetual flux and home to peoples as diverse as their surroundings, peoples who grapple with a broad spectrum of cultural, political and environmental issues as they wrest livelihoods from marginal lands. The cultures, environments and histories of deserts, while fundamentally entangled, are rarely studied as part of a network. To bring different disciplines together, the 1st Oxford Interdisciplinary Deserts Conference in March 2010 brought together a wide range of researchers from backgrounds as varied as physics, history, archaeology anthropology, geology and geography. This volume draws on the diversity of papers presented to give an overview of current research in deserts and drylands. Readers are invited to explore the wide range of desert environments and peoples and the ever-evolving challenges they face

Patterns of cropland management systems for assessments of global change

Die Landwirtschaft liefert einen Großteil der Nahrungsmittel und Rohstoffe für den menschlichen Verbrauch und wird aufgrund globaler Dynamiken des Bevölkerungswachstums, Änderungen der Ernährungszusammensetzung und Auswirkungen des Klimawandels herausgefordert. Gleichzeitig hat die intensive landwirtschaftliche Produktion oft erhebliche Auswirkungen auf die Leistungen und Funktionen von Ökosystemen. Agrarökosystemmodelle können verwendet werden, um Auswirkungen der Landwirtschaft über verschiedene zeitliche und räumliche Skalen zu quantifizieren. Globale Bewertungen werden jedoch durch die begrenzte Verfügbarkeit von Daten einzelner agronomischer Maßnahmen und dem Wissen über die damit verbundenen biophysikalischen und biogeochemischen Prozesse erschwert. Ziel dieser Doktorarbeit ist es, das Verständnis über Anforderungen an Daten von landwirtschaftlichen Produktionssystemen und deren Anwendungsmethoden in globalen Modellierungsstudien zu erweitern. Darüber hinaus zielt diese Doktorarbeit darauf ab die Arten, räumliche Ausdehnung, Umweltwirkung und Potenziale von unterschiedlichen Bewirtschaftungsmethoden auf globalem Ackerland abzuschätzen. Die Ergebnisse der ersten Studie zeigen, inwiefern die Aggregation von rasterzellenbasiert simulierten Ernteerträgen zu national und globalen Durchschnittserträgen mit vier unterschiedlichen Datenprodukten zu Unsicherheiten von ~10 % führen kann. Der zweite Forschungsartikel präsentiert eine Klassifikation von sechs Bodenbearbeitungssystemen, deren Kartierung und ermittelten Merkmale zur Parametrisierung in globalen Agrarökosystemmodell verwendet werden können. Zuletzt werden mit Hilfe des globalem Modells LPJml5.0- tillage-cc die biophysikalischen Auswirkungen von Zwischenfruchtanbau im Vergleich zu Schwarzbrache auf die Kohlenstoff-, Stickstoff- und Wasserdynamiken abgeschätzt. Die Ergebnisse der Thesis zeigen Potenziale von und Trade-offs zwischen ackerbaulichen Bewirtschaftungsmethoden und deren globaler Modellierung auf.Agricultural production provides a major share of food, feed, fiber, and fuel for anthropogenic usage, and is challenged by projected increasing demand due to dynamics of population growth, changes in dietary compositions, and climate change impacts. At the same time, intensive agricultural production practices have environmental externalities, which negatively affect ecosystems’ services and functions. Agroecosystem models can be used to quantify impacts of cropland use across various temporal and spatial scales, but global assessments are hampered by the limited availability of land management data and of knowledge regarding associated biophysical and biogeochemical processes and functions. The objective of the thesis is to increase the understanding of agricultural management data requirements and implications for their usages in global modeling studies. Further, the thesis aims to identify types, spatial distribution, as well as to estimate impacts, and potentials of cropland management practices to support sustainable development. In the first study, it was assessed in which way the application of different harvested crop area datasets for the national and global aggregation of modeled crop yield outputs from the grid cell to country and global scale, induces average uncertainty of ~10 % to the results. The second study presents a global classification of six soil management systems whereas the derived mapping and characteristics can be used for parameterization across a range of intensity levels in global land use modeling studies. In the third study different cropland management practices were assessed using LPJml5.0-tillage-cc, with a modified code for the representation of cover crops growing as grass on cropland between two consecutive main crop growing seasons. The thesis’ findings reveal potential and trade-offs of land management practices and their impact assessment using global agroecosystem models

Changing Deserts

Deserts – vast, empty places where time appears to stand still. The very word conjures images of endless seas of sand, blistering heat and a virtual absence of life. However, deserts encompass a large variety of landscapes and life beyond our stereotypes. As well as magnificent Saharan dunes under blazing sun, the desert concept encompasses the intensely cold winters of the Gobi, the snow-covered expanse of Antarctica and the rock-strewn drylands of Pakistan. Deserts are environments in perpetual flux and home to peoples as diverse as their surroundings, peoples who grapple with a broad spectrum of cultural, political and environmental issues as they wrest livelihoods from marginal lands. The cultures, environments and histories of deserts, while fundamentally entangled, are rarely studied as part of a network. To bring different disciplines together, the 1st Oxford Interdisciplinary Deserts Conference in March 2010 brought together a wide range of researchers from backgrounds as varied as physics, history, archaeology anthropology, geology and geography. This volume draws on the diversity of papers presented to give an overview of current research in deserts and drylands. Readers are invited to explore the wide range of desert environments and peoples and the ever-evolving challenges they face