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Water is an important key to understand Maya society, especially water availability within a context of climatic changes. Increasing drought would have pushed the Maya water systems into collapse. This paper studies the Maya water systems from an action‐oriented perspective, in order to understand what challenges the Maya had to overcome when dealing with water. The systems found at Tikal serve as main example, allowing comparisons with other Maya sites. In this analysis, hydraulic‐ and agent‐based elements are combined in a model to investigate the performance of the water system within extreme weather conditions and changing human agency. The results suggest that the Tikal water system was able to cope with most of the extreme situations. Furthermore, model results allow proposing that the Maya did not anticipate on short‐term changes in external conditions. Generally, in Tikal surpluses of water may have been as important as shortages of water. The extensive system of drains and canals present at Tikal may have been built to move water from the center of the city rather than to supply water to lower situated reservoirs during the dry season. Such a water‐removal system could be less centrally orientated and organized than is often argued. This could also mean that organizational structures of water systems of different city centers (Tikal, Calakmul, and Caracol) were more similar than usually assumed. This article is categorized under: Human Water > Water as Imagined and Represented Engineering Water > Planning Water Science of Water > Water Quality [ABSTRACT FROM AUTHOR]

Securing sustainable livelihood conditions and reducing the risk of outmigration in savanna ecosystems hosted in the tropical semiarid regions is of fundamental importance for the future of humanity in general. Although precipitation in tropical drylands, or savannas, is generally more significant than one might expect, these regions are subject to considerable rainfall variability which causes frequent periods of water deficiency. This paper addresses the twin problems of “drought and desertification” from a water perspective, focusing on the soil moisture (green water) and plant water uptake deficiencies. It makes a clear distinction between long-term climate change, meteorological drought, and agricultural droughts and dry spells caused by rainfall variability and land degradation. It then formulates recommendations to better cope with and to build resilience to droughts and dry spells. Coping with desertification requires a new conceptual framework based on green-blue water resources to identify hydrological opportunities in a sea of constraints. This paper proposes an integrated land/water approach to desertification where ecosystem management supports agricultural development to build social-ecological resilience to droughts and dry spells. This approach is based on the premise that to combat desertification, focus should shift from reducing trends of land degradation in agricultural systems to water resource management in savannas and to landscape-wide ecosystem management. [ABSTRACT FROM AUTHOR]

A response to the commentary on the article "No harvest was reaped: demographic and climatic factors in the decline of the Neo-Assyrian Empire" is presented. The authors note that the premise of their original paper and its purpose has been misread and misjudged. They also stresses that the larger point of their article has been missed out where the proxy records indicate a shift towards drier conditions.

Global climate change is the major and most urgent global environmental issue. Australia is already experiencing climate change as evidenced by higher temperatures and more frequent and severe droughts. These impacts are compounded by increasing land use pressures on natural resources and native ecosystems. This paper provides a synthesis of the interactions, feedbacks and risks of natural climate variability, climate change and land use/land cover change (LUCC) impacting on the Australian continent and how they vary regionally. We review evidence of climate change and underlying processes resulting from interactions between global warming caused by increased concentration of atmospheric greenhouse gases and modification of the land surface. The consequences of ignoring the effect of LUCC on current and future droughts in Australia could have catastrophic consequences for the nation's environment, economy and communities. We highlight the need for more integrated, long-term and adaptive policies and regional natural resource management strategies that restore the beneficial feedbacks between native vegetation cover and local-regional climate, to help ameliorate the impact of global warming. [ABSTRACT FROM AUTHOR]