**Foreword**

Chapter 5 **Water Cycle Process Research: Experiments and**

Lihu Yang, Xianfang Song and Yunfeng Qiao

Chapter 7 **Relation between Infiltration Rate, Cover Materials and**

**Ishikawa Prefecture, Japan 165**

**Areas (South China): A Review 185**

**in Artificially Fractured Rock 197**

**Runoff and Soil Erosion 217**

Chapter 6 **Experimental Study on the Mechanisms of Soil Water-Solute-Heat Transport and Nutrient Loss Control 127** Quanjiu Wang, Beibei Zhou, Lijun Su and Yuyang Shan

Chapter 8 **Field-Controlled Hydrological Experiments in Red Soil-Covered**

Sanyuan Jiang, Qiande Zhu and Seifeddine Jomaa

Chapter 10 **Experimental Variant Slope Soil Tank for Measurements of**

Lihu Yang, Simin Qu, Yifan Wang and Xianfang Song

Chapter 11 **Practice on the Watershed Hydrological Experimental System**

Chapter 12 **Practice on the Watershed Hydrological Experimental System**

**System Complexity: 2. Practice and Test 253**

**System Complexity: 1. Theoretical Study 227**

Xue-Gang Li, Peng Zhuo and Na Yang

Zhuo, Na Yang, Jia-Ju Lu and Wei-Zu Gu

**Reconciling Deterministic and Stochastic Subjects Based on the**

**Reconciling Deterministic and Stochastic Subjects Based on the**

Jiu-Fu Liu, Ai-Min Liao, Niu Wang, Jin Lin, Hong-Wei Liu, Wen-Zhong Wang, Tao Ma, Zhao Cai, Min-Han Liao, Xue-Gang Li, Peng

Wei-Zu Gu, Jiu-Fu Liu, Ai-Min Liao, Niu Wang, Jia-Ju Lu, Jin Lin, Hong-Wei Liu, Wen-Zhong Wang, Tao Ma, Zhao Cai, Min-Han Liao,

Chapter 9 **Fluid Flow, Mass, and Heat Transport Laboratory Experiments**

**Hydraulic Conductivity of Forest Soils in Japanese Cedar and Hiba Arborvitae Plantation Forests under Artificial Rainfall in**

**Observations 107**

**VI** Contents

Yoshitaka Komatsu

Nicola Pastore

Controlled experiments in hydrology are rare. The best ones have helped redefine the field: John Hewlett's trough hillslope experiment at Coweeta in the late 1950s and early 1960s that changed how we conceptualize hillslope drainage, Alan Rodhe's Gardsjon roof experiment in Sweden in the 1980s that helped inform new understanding of hillslope storage and release and its control on concentration-discharge relations, and the Biosphere-2 LEO hillslope led by Peter Troch in the past decade that is opening up new and fundamental understanding of coevolution of hillslope climate, vegetation, and solute weathering. Of course, these experiments allow boundary conditions to be constrained and defined (something rare in field experiments in natural systems) and allow one to study events outside the narrow range of conditions one might be able to "see" in a typical field experiment. As models flourish and usurp much basic field work, controlled experiments and artificial soil blocks, hillslopes, and mini-catchments are increasingly needed to discover new process behaviors and responses and to quantify model performance.

It is against this backdrop that the very useful *Hydrology of Artificial and Controlled Experiments* comes along. Its editors, Jiu-Fu Liu and Wei-Zu Gu from the National Hydraulic Research Institute in Nanjing, are the forefront of such study in China—both linked to the Chuzhou Hydrological Laboratory and the famous Hydrohill experimental hillslope—the single greatest public work efforts in artificial hillslope hydrology. I served on the Biosphere-2 "LEO planning committee" in the years before its construction and can say that many-a-planning-discussion was influenced by what had been done at Hydrohill in the decades prior.

Liu and Gu have done an outstanding job of assembling an impressive list of authors and studies from around the world—from lysimeter studies in Japan to mine cover sites in Germany and laboratory slopes and runoff plots in China along with chapters on LEO and Hydrohill. The book *Hydrology of Artificial and Controlled Experiments* is a comprehensive overview of studies of artificial and controlled experiments today and a useful benchmark for students and practitioners alike.

> *Jeffrey J. McDonnell* Global Institute for Water Security University of Saskatchewan, Saskatoon, Canada

Preface

The river basin, watershed, or catchment is central to many of the concepts in hydrology [1], and scientific hydrology was found in two basin studies in the Seine river basin during the end of the seventeenth century as suggested by UNESCO/WMO/IAHS [2]. However, basin studies developed slowly until the end of the nineteenth century when public demands ac‐ celerated. Since the early twentieth century, a multitude of basin studies have appeared, in‐ cluding the Wagon Wheel Gap experiment of the USA begun in 1910 in two forested basins, the Valdai Branch of the State Hydrological Institute (for field experimental investigations) of the former USSR in 1933, Coweeta Hydrologic Laboratory of the USA set up since 1934, Harz Mountains experiment of Germany begun in 1948, Alrance experiment of France start‐ ed in 1950, Bluebrook Runoff Experiment of China established in 1953, and so on. This can be regarded as the first stage of hydrological experimentation. A period of rapid worldwide development resulted from the representative and experimental basin (EB) program provid‐ ed by the first International Hydrology Decade (UNESCO/IHD) since 1965, with an estimat‐ ed 3000 basin studies conducted over the world during the decade. It can be regarded as the second stage of development. Since this flourishes it has been going on for more than five decades up to now, what faced in the present is a changing nature of great transition with anthropogenic perturbation, replumbing of the hydrologic cycle, and natural climate oscilla‐ tions. In 2006, a paper coauthored by 12 scientists resulted from a CUAHSI vision workshop pointed out that "Yet, most field experiments and observations in watershed science to date, remain largely descriptive. Many of these field studies have not set out to seek fundamental truth or understanding (nor test any formal theory or hypothesis per se)" and "We should instead focus on the development of systematic measurement programs that are specifically targeted to the generation of tests of new theories" [3]. We have to thus aim at the substan‐ tial progress in hydrologic science toward "a new unified hydrologic theory" as Sivapalan has suggested [4]. May we believe that the third stage of the transition of hydrological ex‐

periments of reforming is irresistible, perhaps it has begun already.

measures to manipulate a part of the nature for what we want her to expose.

Werner Heisenberg had warned that "what we observe is not nature herself, but nature ex‐ posed to our method of questioning." Perhaps, there is a misunderstanding in hydrological experiments to place hopes on natural watershed for trying to lift her veil of complexities. In fact even in small scale most natural watershed will keep doggedly her own character of complexity with some degree of organization, it follows that the manipulation experiments very likely can play their unique role to making some changes for it. "Nothing ventured, nothing gained," the venture for watershed experimentation may be using some kind of

Actually, since John Hewlett's trough hillslope experiment at Coweeta in the late 1950s, a lot of development has been achieved including controlled slope, artificial catchment, and even
