Water wars are a prospect in coming years as nations struggle with the effects of climate change, growing water demand, and declining resources. The Indus River supplies water to the world's largest contiguous irrigation system generating 90% of the food production in Pakistan as well as 13 gigawatts of hydroelectricity. Because any gap between water supply and demand has major and far-reaching ramifications, an understanding of natural flow variability is vital-especially when only 47 years of instrumental record is available. A network of tree-ring sites from the Upper Indus Basin (UIB) was used to reconstruct river discharge levels covering the period AD 1452-2008. Novel methods tree-ring detrending based on the 'signal free' method and estimation of reconstruction uncertainty based on the 'maximum entropy bootstrap' are used. This 557-year record displays strong inter-decadal fluctuations that could not have been deduced from the short gauged record. Recent discharge levels are high but not statistically unprecedented and are likely to be associated with increased meltwater from unusually heavy prior winter snowfall. A period of prolonged below-average discharge is indicated during AD 1572-1683. This unprecedented low-flow period may have been a time of persistently below-average winter snowfall and provides a warning for future water resource planning. Our reconstruction thus helps fill the hydrological information vacuum for modeling the Hindu Kush-Karakoram-Himalayan region and is useful for planning future development of UIB water resources in an effort to close Pakistan's ''water gap''. Finally, the river discharge reconstruction provides the basis for comparing past, present, and future hydrologic changes, which will be crucial for detection and attribution of hydroclimate change in the Upper Indus Basin.

Our understanding of the full range of natural variability in streamflow, including how modern flow compares to the past, is poorly understood for the Upper Indus Basin because of short instrumental gauge records. To help address this challenge, we use Hierarchical Bayesian Regression with partial pooling to develop six centuries long (1394–2008 CE) streamflow reconstructions at three Upper Indus Basin gauges (Doyian, Gilgit, and Kachora), concurrently demonstrating that Hierarchical Bayesian Regression can be used to reconstruct short records with interspersed missing data. At one gauge (Partab Bridge), with a longer instrumental record (47 years), we develop reconstructions using both Bayesian regression and the more conventionally used principal components regression. The reconstructions produced by principal components regression and Bayesian regression at Partab Bridge are nearly identical and yield comparable reconstruction skill statistics, highlighting that the resulting tree ring reconstruction of streamflow is not dependent on the choice of statistical method. Reconstructions at all four reconstructions indicate that flow levels in the 1990s were higher than mean flow for the past six centuries. While streamflow appears most sensitive to accumulated winter (January–March) precipitation and summer (May–September) temperature, with warm summers contributing to high flow through increased melt of snow and glaciers, shifts in winter precipitation and summer temperatures cannot explain the anomalously high flow during the 1990s. Regardless, the sensitivity of streamflow to summer temperatures suggests that projected warming may increase streamflow in coming decades, though long‐term water risk will additionally depend on changes in snowfall and glacial mass balance.

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This study reports on the multivariate analysis of the vegetation of Hindukush Range in Pakistan, concentrating on the structure and regeneration potential of Monotheca buxifolia and associated tree species. Twenty stands at different locations in the Dir District of the Hindukush Range in Pakistan were chosen for the study. A point centered quarter method for trees and 5 m  5 m size quadrats were used for the sampling of understorey vegetation, including shrubs, seedlings, and saplings, respectively. The underlying group structure in vegetation was exposed by an agglomerative clustering technique, while major trends were disclosed by DCA ordination. Size class structure and regeneration potential of M. buxifolia and associated tree species were also examined, which reflects the future trend of species and, consequently, the forests where they dominate. The relationships between environmental factors and vegetation were investigated.The arboreal vegetation was mostly dominated by broad leaved species including Monotheca buxifolia, Olea ferruginea, Acacia modesta, Punica granatum, Quercus baloot, and Ficus palmata. Among the understorey vegetation, the abundant species were Dodonea viscosa, Justicia adhatoda, Otostegia limbata, Indigofera gerardiana, Plantago lanceolata, Rumex dentatus, Marrubium vulgaris, Fragaria nubicola, Geranium rotundifolium, Daphne oleoides, Solanum nigram, Ajuga bracteosa, Oxalis corniculata seedlings of Monotheca buxifolia, Quercus baloot, and Punica granatum. At the seedling and sapling stage, the maximum number was observed for Monotheca buxifolia (27±5.75 and 38±7.1), followed by Quercus baloot (18±2.2 and 12±1.0) and Olea ferruginea. As far as regeneration status is concerned, 34% species showed good regeneration, 50% species were facing the problem of poor regeneration while, and only 16% species were not regenerating. Five groups of tree vegetation that emerged from Ward's cluster analysis could readily be superimposed on DCA ordination. These groups were associated with particular elevation and, to a lesser extent, with edaphic variables, such as pH and nutrients. Some of the topographic and edaphic variables, such as soil nutrient, showed significant or weak linear relationships with one or more ordination axes. The size class structure of M. buxifolia and associated tree species for individual stands exhibited a few gaps. Relationships between density and basal area were significant, but the density and basal area with altitudinal and slope gradient showed an insignificant relation. Some recommendations are outlined for future research and sustainable management of these forests species.

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