An overview of the taxonomic instability of endangered Golden and Zhobi mahseer in Pakistan

In South and South East Asia three genera of fish species i.e. Tor, Neolissochilus and Naziritor are commonly known as Mahseer with at least 47 species. Among these 23 belongs to genus Tor, 22 to Neolissochilus and one to Naziritor i.e. Naziritor zhobensis. Recently another species added to genus Naziritor is Naziritor chelynoides in India. Among Tor species Tor putitora (Hamilton) is the most widely distributed Mahseer in Pakistan and other countries of the Indian subcontinent. However, based alone on morphological characters some authors identify the Pakistani counterparts as Tor macrolepis (Heckel), (a species presumed to be found exclusively in the Indus River system) distinct from Tor putitora (a species found in Ganga Brahmaputra River system). In order to resolve this taxonomic ambiguity, present study carried out meristic and morphometric measurements of Mahseer collected from a total of 11 water bodies of Pakistan. Ratios between the morphometric characters were calculated and statistically analyzed using t-test and correlation coefficient. Two species identified as Tor putitora and Naziritor zhobensis were the sole Mahseer inhabitants of Indus system in Pakistan. Tor putitora occurred at all surveyed sites while Nazirtor zhobensis had a distribution range from river Zhob to tributaries of river Gomal the right bank tributaries of River Indus. The study corroborates that there are no unequivocal morphological synapomorphies in any existing populations of both species. The study further demonstrates that head length, a character frequently used in Mahseer taxonomy, is not a good measure for species identification. Finally the present study establishes that Naziritor zhobensis still exists in the water bodies of Pakistan and that golden Mahseer occurring in Indus riverine system of Pakistan is Tor putitora.

Assessment of anthropogenic-causing-agents act on waterbirds-diversity in the vicinity of Tarbela Dam, Indus River, Pakistan

Birds are among the best bio-indicators, which can guide us to recognize some of the main conservation concerns in ecosystems. Anthropogenic impacts such as deforestation, habitat degradation, modification of landscapes, and decreased quality of habitats are major threats to bird diversity. The present study was designed to detect anthropogenic causative agents that act on waterbird diversity in Tarbella Dam, Indus River, Pakistan. Waterbird censuses were carried out from March 2019 to February 2020 in multiple areas around the dam. A total of 2990 waterbirds representing 63 species were recorded. We detected the highest waterbird richness and diversity at Pehure whereas the highest density was recorded at Kabbal. Human activity impacts seemed to be the main factor determining the waterbird communities as waterbirds were negatively correlated with the greatest anthropogenic impacts. Waterbirds seem to respond rapidly to human disturbance.

Appraisal of hydro-ecology, geomorphology, and sediment behavior during low and high floods in the Lower Indus River Estuary

The riverine ecosystem is beholden by the freshwater; however, morphological changes and sediment load destabilize the natural river system which deteriorates the ecology and geomorphology of the river ecosystem. The Lower Indus River Estuary (LIRE) geomorphological response was synthesized using satellite imagery (1986–2020) and evaluated against the field measurements. The estuary sinuosity index has an increasing trend from 1.84 (1986) to 1.92 (2020) and the estuary water area is increased from 101.41 km2 (1986) to 110.24 km2 (2020). The sediment load investigation at Kotri barrage indicated that the median size of bed material samples during the low-flow period falls between 0.100 and 0.203 mm and the bed material after the high flow has clay and silt (<0.0623 mm) ranging from 17–95% of the total weight of samples. The vegetated land loss on the banks is positively correlated with the peak runoff at Kotri barrage (r2=0.92). The bank erosion was computed with high precision (r2=0.84) based on an improved connection of the coefficient of erodibility and excess shear stress technique. This study will be helpful for policymakers to estimate the ecological health of LIRE, and sediment fluxes play an essential role in the mega-delta system and coastal management.

Spatial and temporal variations of hydrodynamics and sediment dynamics in Indus River Estuary,Pakistan

<p>Field investigations were conducted to study the seasonal variation of hydrodynamics and sediment transport in Indus River Estuary (IRE), Pakistan. The data of water levels, currents, salinity, and suspended sediment concentration (SSC) were collected hourly covering both wet and dry seasons. Tidal amplitudes were higher near the mouth than those at the middle and upper estuary. The ebb phase lasted longer than that of the flood during the wet season. The asymmetric tidal pattern with higher ebb velocity was observed during the wet season. A slight difference in current velocity was found during the dry season. The flood currents were higher at middle estuary than those in wet season. During the wet season, salinity variation within a tidal cycle slightly increased from the upper estuary to the mouth. Salinity was substantially higher during the dry season than the wet season at all three stations, with the absence of the flood-ebb variation, showing a strong saltwater intrusion. The SSC data revealed that the sediments were mainly brought into the estuary by freshwater discharge during the wet season. Sediment re-suspension process persists during the dry season, due to the tidal currents. A stronger saltwater intrusion occurred in the dry season due to weak river discharge. An estuarine turbidity maximum zone was formed near station-2 due to the combined effects of tides, river discharge and saltwater intrusion. Overall, field observations have shown a significant spatial and temporal variation in flood/ebb and wet/dry seasons for hydrodynamics and sediment transport in IRE.</p>

Sindh in Transition: From Mughal Rule to British Annexation, Early Eighteenth Century to 1843

<p>The eighteenth century in India saw the decline of the Mughal empire and the rise of several regional states. From the mid-1700s, however, the consolidation of regional states was checked by British expansion in the subcontinent. This thesis is a case study of one regional state, the state of Sindh in present day Pakistan. It engages in the historiographical debates about the relative importance of political and economic factors in explanations of Mughal decline during the eighteenth century. It also addresses questions about the motives that impelled British annexation, and the processes through which annexation was achieved. The study analyses Sindh’s transition from being a peripheral region in the twilight days of the Mughal empire to its annexation by the British in 1843. It is based on some Persian sources, along with British archival records and a number of eighteenth and nineteenth century travelogues. The thesis begins with a study of the process of state formation in Sindh by the Sufi Kalhora tribe. Although increasingly independent from 1701, the Sindh state continued to pay tribute to the Mughals until 1739, then to Persia until 1747, and then to the Afghan king until 1783, when the Talpur Meers replaced the Kalhoras as Sindh’s ruler. Under both the Kalhoras and the Talpurs, a significant expansion of trade helped sustain the Sindh state and resulted in the emergence of a strong mercantile class. The thesis critically examines the role of the new commercial class and its relationship with Sindh’s rulers. But the political edifice constructed by the Talpurs was weak. The thesis argues that when the rise of French and Russian imperialism in the Middle East made Sindh strategically and commercially important to the British, the political weakness of the Talpur regime facilitated British encroachment in Sindh. The final annexation of Sindh in 1843, following two battles with the Meers, was the result of a number of developments: it was the culmination of a long-drawn-out weakening of the Sindhi polity; it was connected to European rivalries in Central Asia and also to the East India Company’s new appreciation of the commercial importance of Sindhi trade along the Indus river. More broadly, the annexation in 1843 needs to be understood in the context of the interplay of British, French, Russian, Afghan, Sikh and Persian ambitions since the beginning of the nineteenth century.</p>

Sindh in Transition: From Mughal Rule to British Annexation, Early Eighteenth Century to 1843

<p>The eighteenth century in India saw the decline of the Mughal empire and the rise of several regional states. From the mid-1700s, however, the consolidation of regional states was checked by British expansion in the subcontinent. This thesis is a case study of one regional state, the state of Sindh in present day Pakistan. It engages in the historiographical debates about the relative importance of political and economic factors in explanations of Mughal decline during the eighteenth century. It also addresses questions about the motives that impelled British annexation, and the processes through which annexation was achieved. The study analyses Sindh’s transition from being a peripheral region in the twilight days of the Mughal empire to its annexation by the British in 1843. It is based on some Persian sources, along with British archival records and a number of eighteenth and nineteenth century travelogues. The thesis begins with a study of the process of state formation in Sindh by the Sufi Kalhora tribe. Although increasingly independent from 1701, the Sindh state continued to pay tribute to the Mughals until 1739, then to Persia until 1747, and then to the Afghan king until 1783, when the Talpur Meers replaced the Kalhoras as Sindh’s ruler. Under both the Kalhoras and the Talpurs, a significant expansion of trade helped sustain the Sindh state and resulted in the emergence of a strong mercantile class. The thesis critically examines the role of the new commercial class and its relationship with Sindh’s rulers. But the political edifice constructed by the Talpurs was weak. The thesis argues that when the rise of French and Russian imperialism in the Middle East made Sindh strategically and commercially important to the British, the political weakness of the Talpur regime facilitated British encroachment in Sindh. The final annexation of Sindh in 1843, following two battles with the Meers, was the result of a number of developments: it was the culmination of a long-drawn-out weakening of the Sindhi polity; it was connected to European rivalries in Central Asia and also to the East India Company’s new appreciation of the commercial importance of Sindhi trade along the Indus river. More broadly, the annexation in 1843 needs to be understood in the context of the interplay of British, French, Russian, Afghan, Sikh and Persian ambitions since the beginning of the nineteenth century.</p>

Seasonal variation of oceanographic processes in Indus river estuary

Field investigations were conducted to study spatial and temporal (seasonal) variations in meteorological, hydrodynamic and hydrological variables in Indus River Estuary. The investigations were undertaken during wet, (moderate fluvial discharge), flood (highest fluvial discharge) and dry (zero fluvial discharge) seasons to obtain surface and near bed data during flood and ebb tides. Tides were semidiurnal, showing an asymmetric pattern with longer ebb tides and shorter flood tides. The hydrodynamic data revealed strong seasonal variation, the ebb velocities were significantly higher than flood current velocities during wet season, whereas a slight difference was found in current velocities during dry season, while the ebb phase lasted longer than flood during wet season; however no significant difference was observed during dry season. On the other hand during flood period the water currents were substantially higher and unidirectional related to the strong river flow. Turbidity values were considerably higher during flood season, than wet and dry seasons along the channel. However hydrological parameters such as temperature and dissolved Oxygen also revealed seasonal and spatial fluctuations, though they were within permissible range. The salinity distribution along the channel was related to the incoming river flow and tidal propagation. Higher salinity values were recorded in dry season, suggested that salinity variation at Estuary was due to salt intrusion from the North Arabian Sea, related to the absent of fluvial discharge form Indus River. Present study revealed substantial changes for hydrology and hydrodynamic conditions of the Indus River Estuary, related to the varying Indus River flow, as well as winds are another important atmospheric force in this region which enhanced the tidal forcing during southwest monsoon.

Hydrological Modeling of the Astore River Basin, Pakistan, by Integrating Snow and Glacier Melt Processes and Climate Scenarios

The upper Indus River basin has large masses of glaciers that supply meltwater in the summer. Water resources from the upper Indus River basin are crucial for human activities and ecosystems in Pakistan, but they are vulnerable to climate change. This study focuses on the impacts of climate change, particularly the effects of receding glaciers on the water resources in a catchment of the upper Indus river basin. This study predicts river flow using a hydrologic model coupled with temperature-index snow and glacier melt models forced by observed climate data. The basin is divided into seven elevation zones so that the melt components and rainfall-runoff were calculated at each elevation zone. Hydrologic modeling revealed that glaciers contributed one-third of the total flow while snowmelt melt contributed about 40%; rainfall contributed to the remaining flow. Some climate scenarios based on CMIP5 and CORDEX were employed to quantify the impacts of climate change on annual river flows. The glacier retreat in the mid and late centuries is also considered based on climate change scenarios. Future river flows, simulated by the hydrologic model, project significant changes in their quantity and timing. In the mid-century, river flows will increase because of higher precipitation and glacier melt. Simulations projected that until 2050, the overall river flows will increase by 11%, and no change in the shape of the hydrograph is expected. However, this increasing trend in river flows will reverse in the late century because glaciers will not have enough mass to sustain the glacier melt flow. The change will result in a 4.5% decrease in flow, and the timing of the monthly peak flow will shift from June to May. This earlier shift in the streamflow will make water management more difficult in the future, requiring inclusive approaches in water resource management.