A review on salinity adaptation mechanism and characteristics of Populus euphratica, a boon for arid ecosystems

2016 ◽  
Vol 36 (6) ◽  
pp. 497-503 ◽  
Author(s):  
Vishnu D. Rajput ◽  
Tatiana Minkina ◽  
Chen Yaning ◽  
Svetlana Sushkova ◽  
Victor A. Chapligin ◽  
...  
2019 ◽  
Vol 11 (23) ◽  
pp. 2856 ◽  
Author(s):  
Tao Du ◽  
Li Wang ◽  
Guofu Yuan ◽  
Xiaomin Sun ◽  
Shusen Wang

Accurate estimates of evapotranspiration (ET) in arid ecosystems are important for sustainable water resource management due to competing water demands between human and ecological environments. Several empirical remotely sensed ET models have been constructed and their potential for regional scale ET estimation in arid ecosystems has been demonstrated. Generally, these models were built using combined measured ET and corresponding remotely sensed and meteorological data from diverse sites. However, there are usually different vegetation types or mixed vegetation types in these sites, and little information is available on the estimation uncertainty of these models induced by combining different vegetation types from diverse sites. In this study, we employed the most popular one of these models and recalibrated it using datasets from two typical vegetation types (shrub Tamarix ramosissima and arbor Populus euphratica) in arid ecosystems of northwestern China. The recalibration was performed in the following two ways: using combined datasets from the two vegetation types, and using a single dataset from specific vegetation type. By comparing the performance of the two methods in ET estimation for Tamarix ramosissima and Populus euphratica, we investigated and compared the accuracy of ET estimation at the site scale and the difference in annual ET estimation at the regional scale. The results showed that the estimation accuracy of daily, monthly, and yearly ET was improved by distinguishing the vegetation types. The method based on the combined vegetation types had a great influence on the estimation accuracy of annual ET, which overestimated annual ET about 9.19% for Tamarix ramosissima and underestimated annual ET about 11.50% for Populus euphratica. Furthermore, substantial difference in annual ET estimation at regional scale was found between the two methods. The higher the vegetation coverage, the greater the difference in annual ET. Our results provide valuable information on evaluating the estimation accuracy of regional scale ET using empirical remotely sensed ET models for arid ecosystems.


2015 ◽  
Vol 56 (7) ◽  
pp. 779-791 ◽  
Author(s):  
Prem Lal Kashyap ◽  
Anuradha Rai ◽  
Ruchi Singh ◽  
Hillol Chakdar ◽  
Sudheer Kumar ◽  
...  

2018 ◽  
Vol 57 (3) ◽  
pp. 307-321 ◽  
Author(s):  
Manzoor Hussain Memon ◽  
Naveed Aamir ◽  
Nadeem Ahmed

Climate change has now become a reality that has intensified the sufferings of people living in arid ecosystems. Decrease in rainfall, rise in temperature and increase in the frequency of extreme events are some of the changes observed in the semi-arid desert of district Tharparkar. For thousands of years, people of Tharparkar are coping with drought and aridity of the land by using indigenous knowledge. However, global changes in the climatic pattern and deterioration of social and economic conditions have pushed the inhabitants of this arid region into extreme vulnerable situation. This paper investigates the link between climate-induced natural disasters, particularly drought, from the perspective of changing climate patterns which have resulted in food insecurity and water scarcity. The paper analyses the rainfall pattern in the last 38 years—dividing it into two periods i.e. from 1975-1994 and 1995-2014. The findings of the paper have challenged the prevailing notions about aridity and rainfall patterns in Tharparkar district. The research found that there is an increase in average annual precipitation in the district with erratic patterns. Thus, the nature of drought in the district has changed from its historic pattern of less or no rainfall to more but erratic rainfall that is more threatening to livelihoods of the people that in turn have multiplier effect on water and food insecurity. In particularly, women are more vulnerable in the absence of social security and lack of basic necessities for their survival amidst drought. For instance, traditionally the burden of managing water resources falls on women, which leads to an increased work load during the time of drought and also water scarcity. JEL Classification: Q54, Q56, Q25, I30 Keywords: Climate, Environment and Development, Drought, Water, Poverty


Author(s):  
Gus Mills ◽  
Margaret Mills

This book demonstrates how cheetahs are adapted to arid savannahs like the southern Kalahari, and makes comparisons with other areas, especially the Serengeti. Topics dealt with are: demography and genetic status; feeding ecology, i.e. methods used for studying diet, diets of different demographic groups, individual diet specializations of females, prey selection, the impact of cheetah predation on prey populations, activity regimes and distances travelled per day, hunting behaviour, foraging success and energetics; interspecific competition; spatial ecology; reproductive success and the mating system; and conservation. The major findings show that cheetahs are well adapted to arid ecosystems and are water independent. Cheetah density in the study area was stable at 0.7/100 km2 and the population was genetically diverse. Important prey were steenbok and springbok for females with cubs, gemsbok, and adult ostrich for coalition males, and steenbok, springhares, and hares for single animals. Cheetahs had a density-dependent regulatory effect on steenbok and springbok populations. Females with large cubs had the highest overall food intake. Cheetahs, especially males, were often active at night, and competition with other large carnivores, both by exploitation and interference, was slight. Although predation on small cubs was severe, cub survival to adolescence was six times higher than in the Serengeti. There was no difference in reproductive success between single and coalition males. The conservation priority for cheetahs should be to maintain protected areas over a spectrum of landscapes to allow ecological processes, of which the cheetah is an integral part, to proceed unhindered.


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