Reconstructing Taiwan’s land cover changes between 1904 and 2015 from historical maps and satellite images

Abstract

A new reconstruction of changes in Taiwan’s land cover and estimated uncertainty between 1904 and 2015 is presented. The reconstruction is made by integrating geographical information from historical maps and SPOT satellite images, to obtain spatially explicit land cover maps with a resolution of 500 × 500 m and distinguishes six land cover classes: forests, grasslands, agricultural land, inland water, built-up land, and bare soil. The temporal resolution is unbalanced being derived from four historical maps describing the land cover between 1904 and 1994 and five mosaic satellite images describing the land cover between 1995 and 2015. The uncertainty of the historical maps is quantified to show the aggregation error whereas the uncertainty of the satellite images is quantified as classification error. Since 1904, Taiwan, as a developing country, has gone through a not unusual sequence of population growth and subsequent urbanization, a decoupling of the demand for agricultural land from population growth, and a transition from shrinking in forest area to forest expansion. This new land cover reconstruction is expected to contribute to future revisions of global land cover reconstructions as well as to studies of (gross) land cover changes, the carbon budget, regional climate, urban heat islands, and air and water pollution at the national and sub-national level.

A combined approach to establishing the timing and magnitude of anthropogenic nutrient alteration in a mediterranean coastal lake- watershed system

“…Diagenetic processes can also lead to post-burial N isotope enrichment of the sediments. Indeed, 14 N is consumed more rapidly than 15 N by denitrifying bacteria, www.nature.com/scientificreports www.nature.com/scientificreports/ which intensifies under anoxic conditions . Thus, the remaining OM pool will be enriched in 15 N, in turn leading to elevated δ 15 N values 80,81 .…”

“…tipping points) in the Earth system especially during what is now termed the Great Acceleration (which began in www.nature.com/scientificreports www.nature.com/scientificreports/ the 1950s and intensified in the 1970s) 10,11 . In contrast, most dramatic changes in Land Use and Cover Changes (or LUCCs) have occurred in the last few centuries, mainly linked to forestry and agro-pastoral activities [12][13][14] . While most of South America is currently undergoing deforestation and land clearing (e.g., the Amazon Basin), Chile has been undergoing a process of reforestation favored by large government subsidies (Forestal Law Decree of 1974).…”

Pristinity, degradation and landscaping: the three angles of human impact on islands

“…Other individual islands with information useful for PDL representation have been included for comparison. For example, Taiwan (Tw), situated ~200 km off the SE Chinese coast, is in an intermediate position (in the PDL diagram) between Corvo (Azores) and Lobos (Canaries), and the opportunities for conservation and restoration are high, especially in the uplands and highlands, where the natural forests are relatively well preserved [58]. Two islands have been chosen to represent the D corner: the island of Malé (Mé), in the Kaafu atoll of the Maldives archipelago, located ~1000 km south of India, and the island of Manhattan (Mh), which is part of New York City (USA).…”

What Determines Forest Farmers’ Participation in Afforestation Programs? Empirical Evidence from a Population-Based Census Survey

“…Firstly, there is a body of literature that focuses on how household and property characteristics affect participation rates. Nguyen et al [5] and Legesse et al [6] find that land ownership, privatization, and security increase participation rates in Vietnam and Ethiopia's afforestation programs. Similarly, Nielsen et al [7] develop a revealed choice model and show that socio-demographic factors and the property's physical characteristics, such as the total area of oak scrub, can affect participation in a conservation program for this species in Denmark.…”

“…Firstly, we examine the determinants of participating in two afforestation programs on plain and sloped land. The vast majority of studies only consider one policy or intervention [5][6][7][8]. This distinction is significant because afforestation programs on plain and sloped land will vary based on the economic incentives to enroll, the financial support provided to participants, and policy details.…”