Humid East Research Articles

Arachnid Assemblage Composition Diverge between South- and North-Facing Slopes in a Levantine Microgeographic Site

Local microgeographic sites subdivided by sharp ecological and climatic contrasts are important platforms for measuring biodiversity patterns and inferring the possible effect of climatic and ecological variables on species distributions and habitat use. Here, we report results from 24 months (September 2019–August 2021) of continuous pitfall trapping collection in Lower Nahal Keziv, Western Upper Galilee, Israel (“Evolution Canyon” II (hereafter—EC II)). This site receives an average annual rainfall of 784 mm and contains two slopes that differ markedly by solar radiation and plant formation. The first is the south-facing slope (SFS), which is characterized as a semiarid garrigue and open grassland. The second is the contrasting north-facing slope (NFS), which is characterized by a more humid East Mediterranean forest. The slopes are separated by a narrow valley bottom (VB). Analysis of ca. 1750 arachnid specimens, collected from 70 pitfall traps along the slopes and valley, indicates significantly different arachnid assemblages between the NFS and SFS, likely due to the differences in solar radiation that affect plant-cover percentage, which in turn affects the arachnid assemblage composition. In addition to 98 arachnid taxa collected and identified to species and morphospecies level, this study resulted in the discovery of two species new to science, which are described as part of this publication (100 arachnid species and 11 additional taxa that were not identified to species, a total of 111 taxa). Our study, moreover, contributes new ecological data on the spatial and temporal distribution of arachnids, and therefore attests to the importance of year-round sampling in an understudied region. Overall, our study enables a better understanding of arachnid diversity and their distributions and serves as a reference for future research aimed at testing the effect of climate change and other environmental factors that influence arachnid assemblages in natural habitats.

A Humid East Asia During the Early Pliocene Indicated by Calcite Nodules From the Chinese Loess Plateau

AbstractUnderstanding the monsoonal climate over East Asia during the warm Pliocene, the closest analog of the future warm climate, could better inform us of the regional hydrological responses to global climate change. However, the variations and controlling mechanisms of the regional hydrology during this warm period are not determined due to discrepancies among different proxy‐derived records. Here we apply a multiproxy approach based on the geochemistry of calcite nodules from a Red Clay sequence located on the southern edge of the Chinese Loess Plateau. Both the trace metal/Ca ratios and the carbon and oxygen isotopic compositions of calcite nodules show low values during 5.4–4.1 Ma and increased during 4.1–3.3 Ma, together indicating a humid climate during the early Pliocene, the onset of drying starting at ∼4.1 Ma and further intensification at 3.6 Ma. The timings of these hydrological transitions are consistent with global temperature changes, underlining the crucial role of meridional thermal gradient in shaping the regional hydroclimate over East Asia by modulating the strength and position of the East Asian summer monsoon.

A Half-Century of Yield Growth along the Forty-First Parallel of the Great Plains

<h3>Abstract</h3> We examine a half-century of crop yield growth along an 800-mile transect in the U.S. Great Plains. The main contributors to growth were non-specific technical change +53%, irrigation +26%, fertilizer +13% and chemicals +10%. Environmental changes were small and had a minor impact. The wide range of agroclimatic conditions produced significant sub-regional deviations. Irrigation was important in the more arid and warmer areas of the west, while fertilizer and chemicals were more important in the humid east. Sensitivity to weather has increased in the rainfed regions of the east while it has decreased in irrigated regions of the west.

Characterization of Multi‐Scale Fluvial Suspended Sediment Transport Dynamics Across the United States Using Turbidity and Dynamic Regression

AbstractThis study explores multi‐scale variability in the relationship between turbidity (Tn) and flow (Q) in 162 watersheds across the contiguous United States. Sites are selected where Tn acts as a good surrogate for suspended sediment concentration. We use dynamic linear models (DLMs) to infer time‐varying parameters of Tn‐Q rating curves at each site, and calibrate a hyper‐parameter of the DLM model () to quantify the degree of dynamicity in the rating curve relationship. The DLM can capture dynamics in the Tn‐Q relationship at the resolution of the data (daily in this study), enabling an analysis of the dynamics across time scales. Regional multivariate regressions are used to identify physiographic features that relate to the magnitude of and spectral signatures in the DLM parameters across sites. Results show that watersheds in the Midwest and Pacific Northwest tend to exhibit more variable Tn‐Q relationships, while these relationships are more stable in watersheds in the humid east and Lower Mississippi River basin. Stream network complexity, soil composition, perennial snow coverage, saturation‐excess overland flow, and modifications to the stream network are associated with the dynamicity in the Tn‐Q relationship. DLM parameters exhibit cyclic behavior at sub‐monthly, sub‐annual, and annual time scales at sites across the country, with annual cycling associated with basin features that reflect watershed sediment availability and the erosive power of rivers. Overall, our analysis highlights significant multi‐scale variability in Tn‐Q relationships across the nation, with important implications for how sediment dynamics should be measured and managed at the watershed‐scale.

Large-scale water development in the United States: TVA and the California State Water Project

ABSTRACT Assessments of large-scale water resources projects in two regions of the United States provide lessons about long-term outcomes. In the humid East, the Tennessee Valley Authority (TVA) serves multiple objectives and is the largest public power enterprise in the nation. In the West, California’s State Water Project serves nearly 27 million people and some 750,000 acres of farmland with extensive infrastructure. Assessing the outcomes of such large-scale projects requires integrated analysis and involves different value propositions. The major lessons are about government actions in river basin and public power systems development and their impacts on agriculture, urban development, and a vulnerable and changing delta ecosystem.

Effects of climate and irrigation on GRACE-based estimates of water storage changes in major US aquifers

Understanding climate and human impacts on water storage is critical for sustainable water-resources management. Here we assessed climate and human drivers of total water storage (TWS) variability from Gravity Recovery and Climate Experiment (GRACE) satellites compared with drought severity and irrigation water use in 14 major aquifers in the United States. Results show that long-term variability in TWS tracked by GRACE satellites is dominated by interannual variability in most of the 14 major US aquifers. Low TWS trends in the humid eastern U.S. are linked to low drought intensity. Although irrigation pumpage in the humid Mississippi Embayment aquifer exceeded that in the semi-arid California Central Valley, a surprising lack of TWS depletion in the Mississippi Embayment aquifer is attributed to extensive streamflow capture. Marked storage depletion in the semi-arid southwestern Central Valley and south-central High Plains totaled ∼90 km3, about three times greater than the capacity of Lake Mead, the largest U.S. reservoir. Depletion in the Central Valley was driven by long-term droughts (⩽5 yr) amplified by switching from mostly surface water to groundwater irrigation. Low or slightly rising TWS trends in the northwestern (Columbia and Snake Basins) US are attributed to dampening drought impacts by mostly surface water irrigation. GRACE satellite data highlight synergies between climate and irrigation, resulting in little impact on TWS in the humid east, amplified TWS depletion in the semi-arid southwest and southcentral US, and dampened TWS deletion in the northwest and north central US Sustainable groundwater management benefits from conjunctive use of surface water and groundwater, inefficient surface water irrigation promoting groundwater recharge, efficient groundwater irrigation minimizing depletion, and increasing managed aquifer recharge. This study has important implications for sustainable water development in many regions globally.

Megasthenes on the Military Livestock of Chandragupta and the Making of the First Indian Empire

AbstractMegasthenes was an eyewitness to the reign of Chandragupta Maurya, maker of the first India-wide empire (from ca. 321 BCE). The army with which he made that empire depended largely upon the supply of men, horses, elephants, and oxen, a sector which may be called military livestock. Megasthenes’ account of this large sector of government expense and the policies under which it operated gives important testimony about the causes of Chandragupta's success, namely the maintenance of a royal monopoly of horses, elephants, and arms, payment of the soldiers in peacetime and war, the demilitarization of the farmers, and the separation of the soldiers from the land. Over the long run of Indian history, from the Mauryan Empire to the present, the environmental roots of the political order lay in the complementary distribution of horse and elephant country, to the dry west and humid east of a line running down the middle of the Subcontinent; that is, respectively, the valleys of the Indus and the Ganga. The dominating power of India has always had its capital in elephant country, the valley of the Ganga, in cities from Pataliputra (Patna) to Kanauj to Delhi, in a position from which to control the eastward flow of horses and the westward flow of elephants to other states.

Vegetation Response to Elevated CO2 Slows Down the Eastward Movement of the 100th Meridian

AbstractThe 100th meridian is a conceptual arid‐humid divide that effectively bisects the continent of the United States into the humid east and arid west. Here, we examine the historical and future shifts of the 100th meridian from atmospheric, hydrologic, and agroecological perspectives. We find that the effective arid‐humid divide regarding vegetation greenness and runoff has been moving toward west with a mean shift of 0.73° (1982–2015) and 2.08° (1961–2010), respectively, suggesting decreased agroecological and hydrologic aridity in the region. For future periods, the agroecological divide shows a persistent westward movement, whereas eastward shifts of the 100th meridian are detected from the atmospheric and hydrologic perspectives. Nevertheless, the eastward movements of the atmospheric and hydrologic divide substantially slow down when the vegetation response to elevated atmospheric CO2 is accounted for. This finding demonstrates that CO2 fertilization on vegetation could largely alleviate the warming‐induced drying tendency around the 100th meridian region.

Phylogeography of the Rufous Vanga and the role of bioclimatic transition zones in promoting speciation within Madagascar

Madagascar is known as a biodiversity hotspot, providing an ideal natural laboratory for investigating the processes of avian diversification. Yet, the phylogeography of Madagascar’s avifauna is still largely unexamined. In this study, we evaluated phylogeographic patterns and species limits within the Rufous Vanga, Schetba rufa, a monotypic genus of forest-dwelling birds endemic to the island. Using an integrative taxonomic approach, we synthesized data from over 4000 ultra-conserved element (UCE) loci, mitochondrial DNA, multivariate morphometrics, and ecological niche modeling to uncover two reciprocally monophyletic, geographically circumscribed, and morphologically distinct clades of Schetba. The two lineages are restricted to eastern and western Madagascar, respectively, with distributions broadly consistent with previously described subspecies. Based on their genetic and morphological distinctiveness, the two subspecies merit recognition as separate species. The bioclimatic transition between the humid east and dry west of Madagascar likely promoted population subdivision and drove speciation in Schetba during the Pleistocene. Our study is the first evidence that an East-West bioclimatic transition zone played a role in the speciation of birds within Madagascar.

Spatial–Temporal Variation of ANPP and Rain-Use Efficiency Along a Precipitation Gradient on Changtang Plateau, Tibet

Aboveground net primary productivity (ANPP) and rain-use efficiency (RUE) are important indicators in assessing the response of ecosystems to climate change. In this paper, the Changtang Plateau in the Tibetan Autonomous Region was selected as the study area to analyze the spatial and temporal changes of ANPP and RUE in grassland communities and their response to climate change. The results showed the following:(1) The spatial pattern of ANPP was closely related to rainfall on the Changtang Plateau. The average ANPP over the past 15 years increased gradually from the arid west to the humid east. A consistent pattern was exhibited in different grassland types and climate zones. (2) The RUE was higher at the east and west edges of the Changtang Plateau, especially in the arid west, but was lower in the center. From the perspective of different climatic zones, the average RUE in the southern Tibetan semiarid climate zone and the Ngari arid climate zone was significantly higher than that in other climate zones. However, the average RUE in different grassland types only varied from 0.07 to 0.09 g·m−2·mm−1. The spatial variation in RUE was more distinct in different climatic zones than in different grassland types. (3) Climate change influenced the interannual variation of ANPP and RUE, but the response of ANPP to rainfall showed a significant lag. The interannual change in RUE was negatively correlated with changes in precipitation. (4) In general, a greater area showed a significant increase rather than a decrease in ANPP on the Changtang Plateau, which meant that the grassland condition is improving. The temporal variation patterns of ANPP and RUE in different climate zones were consistent with the overall patterns on the Changtang Plateau, while the variation was not significant in different grassland types.

Termination of fluvial-alluvial sedimentation in the Xining Basin, NE Tibetan Plateau, and its subsequent geomorphic evolution

The Xining Basin in northern China lies topographically in the transitional zone between the Tibetan Plateau and the Loess Plateau, and climatically in the transitional zone between humid East Asia and the arid Asian interior. During the Cenozoic, the basin accumulated a thick, continuous sequence of fluviolacustrine-dominated red beds and subsequent eolian loess. The termination of sediment deposition in the Xining Basin is the key to understanding its subsequent evolution, the development of the modern Yellow River, and the history of dust deposition. Here we present the results of a detailed paleomagnetic study of the upper sedimentary sequence of the Xining Basin below the river terraces, and in addition we review previous studies of river evolution development. Our results indicate that the age of the uppermost part of the continuous sequence of fluviolacustrine-dominated red beds in the Xining Basin ranges from ca. 20Ma to 4.8Ma, suggesting that basin sedimentation ended at the earliest at 4.8Ma, and they also provide an earliest age constraint for the subsequent river terrace development and eolian dust deposition. In addition, these results demonstrate that the termination of sedimentation in the Xining Basin and the nearby Linxia Basin was approximately coeval, suggesting the rapid regional tectonic uplift of the NE Tibetan Plateau and resulting reorganization of the landforms and development of the paleo-Yellow River in the late Pliocene.

Ecosystem services in managing residential landscapes: priorities, value dimensions, and cross-regional patterns

Although ecosystem services have been intensively examined in certain domains (e.g., forests and wetlands), little research has assessed ecosystem services for the most dominant landscape type in urban ecosystems—namely, residential yards. In this paper, we report findings of a cross-site survey of homeowners in six U.S. cities to 1) examine how residents subjectively value various ecosystem services, 2) explore distinctive dimensions of those values, and 3) test the urban homogenization hypothesis. This hypothesis posits that urbanization leads to similarities in the social-ecological dynamics across cities in diverse biomes. By extension, the thesis suggests that residents’ ecosystem service priorities for residential landscapes will be similar regardless of whether residents live in the humid East or the arid West, or the warm South or the cold North. Results underscored that cultural services were of utmost importance, particularly anthropocentric values including aesthetics, low-maintenance, and personal enjoyment. Using factor analyses, distinctive dimensions of residents’ values were found to partially align with the Millennium Ecosystem Assessment’s categories (provisioning, regulating, supporting, and cultural). Finally, residents’ ecosystem service priorities exhibited significant homogenization across regions. In particular, the traditional lawn aesthetic (neat, green, weed-free yards) was similarly important across residents of diverse U.S. cities. Only a few exceptions were found across different environmental and social contexts; for example, cooling effects were more important in the warm South, where residents also valued aesthetics more than those in the North, where low-maintenance yards were a greater priority.

Hydrological changes facilitated early rice farming in the lower Yangtze River Valley in China: A molecular isotope analysis

The prosperity of Neolithic rice agriculture along the Yangtze River Valley (China) under the humid East Asian Monsoon has been well documented. However, the way in which major hydrological changes influenced the expansion of rice farming remains elusive, mainly because detailed climate records associated with critical periods of the development of early rice farming are still lacking. Here we present high-resolution n -alkane carbon (δ 13 C) and hydrogen (δD) isotope data sampled every 5 cm from a 360 cm sedimentary sequence spanning an ∼5 k.y. period at the Tianluoshan archaeological site in China’s eastern coastal region. Combined with micropaleontological records, our dual isotope data reveal a detailed climate change profile between 7.0 and 4.6 ka, showing major hydrological changes that coincided with the early development of rice farming in the lower Yangtze region. Two major evapotranspiration events, indicated by synchronized positive δ 13 C and δD shifts of as much as 5‰ (δ 13 C) and 60‰ (δD), are evident ca. 7.0 ka and 6.4 ka, and coincided with regional sea-level changes. Our new isotope data suggest that these short drought climate conditions superimposed upon local sea-level regressions opened suitable new habitats for expanding rice agriculture in the lower Yangtze Delta when subsequent humid climate regimes returned.

Two Heavy Rainfall Types over the Korean Peninsula in the Humid East Asian Summer Environment: A Satellite Observation Study

Abstract A total of 10 years (2002–11) of Tropical Rainfall Measuring Mission (TRMM) Precipitation Radar (PR) reflectivities, signaling heavy rainfall (&amp;gt;10 mm h−1), were objectively classified by applying the K-means clustering method in order to obtain typical reflectivity profiles associated with heavy rainfall over East Asia. Two types of heavy rainfall emerged as the most important rain processes over East Asia: type 1 (cold type) characterized by high storm height and abundant ice water under convectively unstable conditions, developing mostly over inland China; and type 2 (warm type) associated with a lower storm height and lower ice water content, developing mostly over the ocean. These two types also show sharp contrasts in relation to their seasonal changes and in the diurnal variation of frequency maxima, in addition to other contrasting meteorological parameters. The PR-derived heavy rain events were observed over the Korean peninsula and their spatiotemporal evolution was examined using 10-yr composites of 11-μm brightness temperature from geostationary satellites and Interim ECMWF Re-Analysis (ERA-Interim) data. Cold-type heavy rainfall over Korea is characterized by an eastward moving cloud system with an oval shape while the warm type shows a comparatively wide spatial distribution over an area extending from the southwest to northeast. Overall the warm-type process appears to link the low-level moisture convergence area to the vertically aligned divergence area formed over the jet stream level. This setup continuously pushes air upward under moist-adiabatically near-neutral conditions and thus yields heavy rainfall. As warm-type heavy rainfall persists longer, it is considered to be more responsible for flood events occurring over the Korean peninsula.

Streetscape Environmentalism: Floods, Social Justice, and Political Power in San Antonio, 1921–1974

Streetscape Environmentalism: Floods, Social Justice, and Political Power in San Antonio, 1921–1974 Char Miller (bio) Click for larger view View full resolution Map of prominent water features of San Antonio’s west side. Map by Charles D. Grear. [End Page 158] You can locate Zarzamora Creek on the map: type in its coordinates on Google Earth—N 29°31, W 98°34—and you will have pinpointed its cartographical location. But that digital representation will tell you little about its environmental significance or its cultural meaning to the city of San Antonio. Often bone-dry, the Zarzamora is an eight-mile dusty channel that falls away from the Hill Country to the northwest of the urban core. The creek first twists and turns in a south-westerly direction, breaks south and east before flowing into a retention pond known as Elmendorf Lake, merging there with Apache Creek. Their combined stream flow then presses into San Pedro Creek a mile or so above its confluence with the San Antonio River. The Zarzamora is thus a small part of the San Antonio’s 4,180 square-mile drainage system. Perhaps the Zarzamora’s frequent dryness and small size are why the Spanish, who gave the creek its name, neglected to demarcate its presence in their eighteenth-century maps of this sprawling watershed, which made arable the river valley where they sited five religious missions, built a civilian community and a presidio, and irrigated innumerable farms and [End Page 159] ranches. For these colonists, like most modern-day San Antonians, Zarzamora Creek left an almost-invisible mark on the South Texas landscape. But the Zarzamora has a habit of becoming quite noticeable when it rains. Then, what appears unimportant and practically indecipherable becomes overwhelming in significance and force. To account for this startling transformation, start with the confluence of meteorology and topography. San Antonio lies just east of the 100th meridian, long identified as the break point between the humid East and arid West. But this meteorological boundary is not as fixed as the meridian appears on a map, and depending on whether the Pacific Ocean is in an El Niño or La Niña cycle, San Antonio oscillates between deluge and drought. The amount of rain that can fall is startling: the prevailing southeasterly breezes pull supersaturated air up from the Gulf of Mexico that rises as it reaches San Antonio and the Hill Country. Should this uplift collide with a wall of high-pressure air or a cold front pushing down from the north, the resultant storms can produce lightning and earthshaking thunder, and can quickly drench and race across parched ground. In late June and early July 2002, for instance, upwards of thirty-five inches fell in seven days, and the two major rivers that cut through the city, the San Antonio and the Medina, registered record heights; tragically, twelve people lost their lives. On October 17–18, 1998, the same scenario had occurred after a cold front slammed into the region’s high humidity, which then was supercharged by “a plume of moist mid- and high-level air . . . streaming across the area from Hurricane Madeline off the west coast of Mexico.” More than twenty inches of rain fell in twenty-four hours, killing eleven.1 The problem was not solely how much precipitation slanted down as where and how it landed. The Hill Country, and the larger Edwards Plateau of which it is a part, serve as an elevated catchment basin; as rainwater hits and cascades down its slopes, it is funneled into channels that over the millennia have been carved into the limestone terrain. From Austin to San Antonio, a series of rivulets, creeks, and streams carry these turbulent floodwaters to the flatlands, where they power into the Little Colorado or San Marcos, Guadalupe or San Antonio Rivers, which carry the churning flow south and east into the Gulf of Mexico. This complex combination of weather patterns, geological structures, and riparian systems, along with the killer surges they regularly produce, has led the National Weather Service to dub south-central Texas “Flash-Flood Alley.”2 Zarzamora Creek has contributed its share to that...

Evaluation and calibration of simple methods for daily reference evapotranspiration estimation in humid East China

The current study aims to improve the performance of simple methods for the estimation of daily reference evapotranspiration (ET0) in humid East China, namely Priestley–Taylor 1972 (P-T 1972), Hargreaves–Samani 1985 (H-S 1985) and Turc 1961 (TU 1961). These methods were evaluated and calibrated based on well-watered grass lysimeter experiments. The FAO-56 Penman–Monteith equation (FAO-56 PM) is the best method, and the radiation-based methods (TU 1961 and P-T 1972) perform much better than the temperature-based method (H-S 1985). In the simple methods, the coefficients are calibrated to: 1.34 for P-T 1972; 0.0186, 23.47 and 17.06 for TU 1961; and 0.0027 and 0.449 for H-S 1985. The locally calibrated TU 1961 and P-T 1972 perform much better than the original, with either the observed ET0r or the ET0c obtained by FAO-56 PM as standard. However, local calibration does not significantly improve the performance of the H-S 1985 method. In humid East China, FAO-56 PM is the best method for daily ET0 calculation. TU 1961, especially if locally calibrated, is the optimal choice as a simple substitute for FAO-56 PM when solar radiation is available. Otherwise, serious local calibration is strongly recommended before applying H-S 1985 for daily ET0 estimation.

A novel thermal index improves prediction of vegetation zones: Associating temperature sum with thermal seasonality

Thermal variation plays a crucial role for governing the type and distribution of vegetation, especially in the humid region. This paper aims to provide a modified thermal index, effective warmth index (EWI) which associate temperature sum with thermal seasonality, compared with commonly used other indices for classifying and predicting of vegetation zones through a case study of Taiwan. With these different thermal indices calculated and mapped at a 100-m spatial resolution, the corresponding climate-vegetation classification schemes are applied to predict the vegetation zones. The accuracy of spatial prediction is evaluated with Kappa coefficient, referring to 651 sampling plots of vegetation. The prediction of potential natural vegetation zones using EWI is the best one (Kappa=0.759), compared with other indices. This result suggests that thermal seasonality is effective for improving the prediction of warmth index in explaining the altitudinal zonation and distribution of vegetation in Taiwan, and potentially in humid East Asia.

Biogeography of Old World emballonurine bats (Chiroptera: Emballonuridae) inferred with mitochondrial and nuclear DNA

Extant bats of the genus Emballonura have a trans-Indian Ocean distribution, with two endemic species restricted to Madagascar, and eight species occurring in mainland southeast Asia and islands in the western Pacific Ocean. Ancestral Emballonura may have been more widespread on continental areas, but no fossil identified to this genus is known from the Old World. Emballonura belongs to the subfamily Emballonurinae, which occurs in the New and Old World. Relationships of all Old World genera of this subfamily, including Emballonura and members of the genera Coleura from Africa and western Indian Ocean islands and Mosia nigrescens from the western Pacific region, are previously unresolved. Using 1833bp of nuclear and mitochondrial genes, we reconstructed the phylogenetic history of Old World emballonurine bats. We estimated that these lineages diverged around 30 million years ago into two monophyletic sister groups, one represented by the two taxa of Malagasy Emballonura, Coleura and possibly Mosia, and the other by a radiation of Indo-Pacific Emballonura, hence, rendering the genus Emballonura paraphyletic. The fossil record combined with these phylogenetic relationships suggest at least one long-distance dispersal event across the Indian Ocean, presumably of African origin, giving rise to all Indo-Pacific Emballonura species (and possibly Mosia). Cladogenesis of the extant Malagasy taxa took place during the Quaternary giving rise to two vicariant species, E. atrata in the humid east and E. tiavato in the dry west.

Grain-size characteristics and climate variability in TMS5e sequence of Tumen section in southern Tengger Desert, northwestern China

The TMS5e sequence from the Tumen section, at the southern edge of Tengger Desert in the northwestern China, is synchronous with Marine Isotope Stage 5e (MIS5e). It consists of 16 layers of aeolian dune sands, 11 layers of lacustrine loess-like facies, and 5 layers of lacustrine facies. The results of grain-size analysis shows that the palaeo-mobile dune sands, palaeo-fixed to semi-fixed dune sands and loess-like sandy loams are mainly composed of sands, ranging from 70% to 96%; their silt contents ranged from 4% to 20%, and their clay contents ranged from 1% to 5%; the climate under which the aeolian dune sands were deposited is similar to that under which modern mobile dune sands form, which is caused by the dominance of the cold, dry East Asian winter monsoon. In contrast, the lacustrine loess-like facies and lacustrine facies had a lower sand contents than those of the three aeolian dune sands, but have higher silt and clay contents, most of their sand content ranged from 30% to 60%, their silt contents ranged from 35% to 55%, and their clay contents ranged from 6% to 20%. The lacustrine loess-like facies and lacustrine facies formed under the influence of the warm, humid East Asian summer monsoon based on their similarity with modern sediments. The grain-size indicator Mz (mean grain diameter) and the SC/D value in the TMS5e sequence indicate climatic instability at the southern edge of the Tengger Desert during MIS5e, with at least 14 fluctuations between a warm, humid climate and a cold, dry climate, divided into five stages: TMS5e5 (139 kyr to 129.3 kyr B.P.), TMS5e4 (129.3 kyr to 124 kyr B.P.), TMS5e3 (124 kyr to 119.5 kyr B.P.), TMS5e2 (119.5 kyr to 116.5 kyr B.P.), and TMS5e1 (116.5 kyr to 113.7 kyr B.P.). These correspond roughly to MIS5e5, MIS5e4, MIS5e3, MIS5e2, and MIS5e1, respectively, in the GRIP ice core data.

Tushaar Shah: Taming the Anarchy: Groundwater Governance in South Asia

South Asian groundwater seems a narrow subject ill suited to an exploration of the socio-ecology of natural resource development and exploitation. Yet Tushaar Shah’s new book Taming the Anarchy takes a historical perspective on water resources and agrarian production in an intriguing treatment of irrigation governance that has implications beyond South Asia or just groundwater. Shah’s synthesis of irrigation technology as the means of agrarian livelihood, with social and political organization framing the evolving modes of production, offers new insights of interest to a broad Human Ecology readership. Mounting pressure on resources, collusion among farmers and officials, agencies working at cross-purposes: allout battle characterizes groundwater “anarchy” in South Asia. The contemporary era—from roughly the 1960s—is the latest phase in the long history of South Asian irrigation. This latest era is marked by an explosion in number, geographical extent, and importance to overall irrigation of private groundwater wells. Shah’s extensive review of studies and statistics from India and Pakistan, and to a lesser degree from Nepal, Sri Lanka, and Bangladesh, constitute the supporting empirics. The state—ever a step behind the unfolding reality on the ground—ineffectively manages or even fully comprehends the groundwater revolution in South Asia. The implications Taming the Anarchy has for future decision-making center on the elusive dynamic between policy and anarchy. Yet Shah only partially resolves this tension, leaving important questions open for further enquiry. The typology of groundwater institutions (pp. 155ff) is normative but not ultimately reductionist to the South Asian context. Specific insights are drawn from broader international experience, including China, the United States, Mexico, Australia, Spain, the Middle East, and SubSaharan Africa. Missing entirely is a review of Soviet-era irrigation that informed the command-and-control model of public administration in India during the Green Revolution’s privately financed groundwater explosion. Shah posits that the forms groundwater governance takes are produced by the interaction of users at multiple institutional scales with the physical resources they use or vie for. This analytical approach holds broad descriptive value but ineffectively accounts for the transformation among institutional forms. Innovation and evolution—what the final chapter’s “thriving in anarchy” are all about—remain inadequately explained, partly by Shah’s own admission. The first of eight chapters, “The Hydraulic Past: Irrigation and State Formation” historically contextualizes the “era of atomistic irrigation” (p. 29), specifically in the Mughal and British colonial periods. A particularly helpful section relates the modern irrigation experience in South Asia to colonial and postcolonial experiments in irrigation from other regions: West Asia and North Africa, humid East and Southeast Asia, and Africa. Shah engages theoretically with Foucault and Wittfogel, among others, to understand the differential efficacy of “constructive imperialism” across time and space, as well as to broach the relation of hydraulic interventions to state formation. Data on irrigation types, area, and users reveal the increasingly important role of groundwater relative to surface water in the irrigation economies of South Asia. C. Scott (*) Udall Center for Studies in Public Policy and School of Geography & Development, University of Arizona, Tucson, AZ, USA e-mail: cascott@email.arizona.edu