1. Introduction

help to mitigate the climate change. This chapter also provides an example of how tropical forests provide supporting services for cultural and economic development of the communi‐

Moving into an example of changes in regulatory services caused by land use change in tropical forests, the chapter by Oliveira et al. focuses on characterizing and analyzing the temporal dynamics of precipitation and evapotranspiration in the Atlantic rainforest of Bra‐ zil in the first decade of 21st century. By using the global remote sensing data and disaggre‐ gate into regional scale, they were able to analyze the changes in the hydrological variables

As an additional example of regulatory services provided by tropical forests, the book closes with a discussion on the role of land use change in the alteration of nutrient cycling by Viera et al. The authors explored nutrient cycling in the Atlantic forest of Brazil from both ecologi‐ cal and environmental aspects. In this chapter, the authors offer a general description about the biome and how different nutrients transferred in the ecosystem, and how land use

All things considered, these five chapters provide a first glimpse of the current research done on tropical forests and land use change processes. They are an introduction to the re‐ search being done around the globe in connection to this topic. We hope the readers from academia, management, conservation, and any other stakeholders will enjoy reading this book and regard it as an initial source of information and study cases on what is the role

The Editors want to finish this preface acknowledging the collaboration and hard work of all the authors. We are also thankful to the Publishing Team of InTech for their continuous sup‐ port and assistance during the creation of this book. Special thanks are due to Mrs. Andrea Koric for inviting us to lead this exciting project and for coordinating the different editorial tasks. Last but not least, we want to acknowledge InTech´s and the authors´ generosity and social commitment by making research from tropical and developing countries available for

**Dr. Juan A. Blanco**

Associate Professor

**Dr. Yueh-Hsin Lo**

Pamplona, Navarra, Spain

Pamplona, Navarra, Spain

**Prof. Dr. Shih-Chieh Chang**

Senior Researcher & Marie Curie Research Fellow

National Dong Hwa University, Hualien, Taiwan

Research Associate & Marie Curie Research Fellow

Dep. Of Environmental Sciences, Public University of Navarre,

Department of Natural Resources and Environmental Studies,

Dep. Of Environmental Sciences, Public University of Navarre,

in this region that can be linked to changes in land use change.

ties living on them.

VIII Preface

change could affect them.

free.

that biodiversity plays in ecosystems.

Large regions of different ecosystems around the world (forests, grasslands, wetlands, farmlands, water bodies) are being managed for different uses, usually implicating the substitution of one ecosystem type for another. This process, known as land use change, is driven by the need to provide food, fiber, water, and shelter to more than seven billion people. Land use change has therefore moved from being a local environmental issue to becoming one of the most important causes of global change [1]. However, such changes in how humans use the land have caused global croplands, pastures, plantations, and urban areas to expand their surfaces in recent decades. In other words, humans are using an increasing share of the planet surface and its resources, accompanied by large increases in energy, water, and fertilizer consumption, along with considerable losses of biodiversity. As a consequence, ecosystems' structures and functions are being increasingly altered, potentially undermining the capacity of ecosystems to sustain food production, maintain freshwater, regulate climate and air quality, ameliorate infectious diseases, and provide a large list of ecosystem services, usually as ignored as important they are [1].

We therefore face the challenge on how to maintain ecosystem services provided by tropical forests, while at the same time tropical regions experience important land use changes. The challenge is made even more complex by the difficulty of providing rules of thumb that can be easily applied across many different types of tropical forests. Differences between regions in forestry and agricultural management, good consumption, trade, culture and of course in ecological structure and function make generalization almost impossible.

Globally, forest cover has been reduced by 7–11 million km<sup>2</sup> over the last 300 years, mainly to make room for agriculture and timber extraction [2, 3]. On the other hand, the increase in technification and market development has led to the expansion of intensively planted forests, first in North America and Europe, but increasingly in South America, Africa, and the Asia-Pacific region, covering now 1.9 million km<sup>2</sup> worldwide [4]. Although impressive, only the 3%

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of the world forest land is covered with productive forest plantations. However, this area expanded by 2 million ha annually in the 1990s and by 2.8 million ha in the 2000s [5].

All forest regions (tropical, subtropical, temperate, sub-boreal, and boreal) are being affected by land use change processes. In particular, tropical forests have suffered from the biggest changes (both positive and negative) of all the forest types although the loss rate is still 3.6 times bigger than the rate of surface gain [6]. These authors estimated that losses in tropical forests area accounted for 32% of total forest loss in the world, with half of those losses being concentrated in South American tropical forests. However, there are big differences among tropical countries in rates of loss and gain of forest area. For example, Brazil has recently shown a decline in annual forest area loss, moving from a high of over 40,000 km<sup>2</sup> year−<sup>1</sup> in 2004 to a low of under 20,000 km<sup>2</sup> year−<sup>1</sup> in 2011. On the other side, for the same period Indonesia has gone from losing 10,000 km2 year−<sup>1</sup> in 2003 to over 20,000 km<sup>2</sup> year−<sup>1</sup> in 2012. In addition, subtropical forests are experiencing important land use change, with many planted forests being usually treated as crops, causing that old-growth natural forests to be relatively rare in these biomes [7]. As a result, although the absolute losses in surface are not as big as in the tropics, subtropical forests have experienced the largest relative changes in forest cover losses and the smallest relative gains [6].

Tropical forests have been extensively disturbed by human beings since long time, and the intensity and extent of disturbance will continue into the future [8]. Land use change in the tropics is caused mainly for agricultural use [9]. Land use change will affect ecosystem services, and climate change makes this a more complicated but emergent problem for human beings [10]. Many land use practices still widely extended in tropical forests (e.g., fuel-wood collection, forest grazing, and road expansion) can degrade forest ecosystem conditions—in terms of productivity, biomass, stand structure, and species composition—even without changing forest area. Changing the way the land is used also paves the way for the introduction of invasive species, including pests and pathogens that can degrade the original forests. Another major change is the alteration of fire regimes, by modifying fuel loads, removing coarse woody debris, increasing the number and frequency of ignition sources, and even modifying the local meteorological conditions [11]. On the other hand, human activity can also improve forest conditions, either by direct forest management or by unintended effects of other processes, such as increased nitrogen deposition, atmospheric concentrations of CO2, and peatland drainage. Such processes have caused the increase in standing biomass of European forests by 40% between 1950 and 1990, while their area remained largely unchanged, accelerating forest growth in the twentieth century [12]. These forests have become a substantial sink of atmospheric carbon [13], although other ecosystem services including those provided by peatlands and biodiversity are likely diminished.

#### 2. Land use change and biodiversity

All kinds of ecosystem services rely on the interplay of the organisms and the abiotic environmental factors of the ecosystems. Therefore, biodiversity of an ecosystem is the key property behind ecosystem services. Globally, the biodiversity is decreasing mainly due to the anthropogenic interferences [14]. Land use change has its first and direct impact on the land surface with the modification or removal of current organisms and thus will change the biodiversity to some extent. In the recent analysis of the intactness of biodiversity, as defined as the proportion of natural biodiversity remaining in local ecosystems, Newbold et al. [15] indicated that the 58% of the planet´s terrestrial ecological boundaries have been crossed. The main cause of this problem is the extensive land use changes that have disconnected natural ecosystems and rounded them up with human-made landscapes.

Land use change from forests worldwide has made ecosystem fragmentation a serious problem. Currently, 70% of the forest cover on Earth is within 1 km from the edge of the forests [16], indicating the loss of connectivity and the vulnerability to further disturbances. In a detailed modeling [17], the spatial patterns of fragmentation in Brazil were shown to have a strong effect on the final extent of influences on ecosystem services like biodiversity. For example, the farmland expansion on the forest edge would have much less impact on biodiversity and carbon storage compared to the farmland increase in the center of a forest. In the case of bird species richness, the fragmentation regime of forests plays a key role. Bregman et al. [18] analyzed the sensitivity to fragmentation of different bird species worldwide and found that the insectivores and large frugivorous are more negatively affected in larger forest fragmentations. This pattern is especially significant in the tropical area.

Barnes et al. [19] demonstrated a 45% reduction in soil invertebrate biodiversity after the conversion of tropical rainforests to oil palm plantations. They further calculated the change in ecosystem energy flux due to this land use change and found a surprisingly lower energy flux in oil palm plantations (51%) relative to what happens in the rainforest. Changes in biodiversity at the functional group level were also evident in a case study in Malaysian Borneo [20]. When comparing the community composition of dung beetles along a land use change gradient from primary forest to logged forest and oil palm plantation, the composition did change substantially. However, significant reduction in functional diversity only happened in the oil palm plantation.

Land use change modifies not just the biodiversity of higher plants and animals, but also that of microorganisms. Paula et al. [21] demonstrated that the change from Amazonian rainforests to pastures would decrease the microbial functional gene richness and diversity. The recovery from the disturbed lands to secondary forests may make the functional gene richness and diversity again similar to that in the primary forests, although not totally alike.

There are many different types of classifying ecosystem services, but a basic classification divides them into three main categories [22]. First, provisioning services are those related to goods generated by the forests that can be directly consumed: timber, food, water, fuel, medicinal plants, etc. Second, regulatory services are those that regulate the conditions in which humans inhabit the land and in which our economic activities take place: climate regulation, flood control, etc. Third, cultural services such as spiritual connection, recreation opportunities, cultural legacy, and sense of belonging are connected to ecosystems.
