Restoration and reconstruction of the degraded Tarim River ecosystem is an important challenge. A goal of an ecological water conveyance project is to protect and restore the natural vegetation in the lower reaches of...Restoration and reconstruction of the degraded Tarim River ecosystem is an important challenge. A goal of an ecological water conveyance project is to protect and restore the natural vegetation in the lower reaches of Tadm River by transferring water from Bosten Lake, through the river channel, to the lower reaches. This study describes the changes in groundwater depth during the water transfer and the respondence of riparian vegetation to alterations in groundwater levels. The results indicate that groundwater depth along the Tarim River channel has a significant spatial-temporal component. Groundwater levels closest to the river channel show the most immediate and pronounced changes as a response to water transfer while those further away respond more slowly, although the observed change appears to be longer in duration. With a rise in the groundwater level, natural vegetation responded with higher growth rates, biomass and biodiversity. These favorable changes show that it is feasible to protect and restore the degraded natural vegetation by raising the groundwater depth. Plant communities are likely to reflect the hysteresis phenomenon, requiting higher water levels to initiate and stimulate desired growth than what may be needed to maintain the plant community. Because different species have different ecologies, including different root depths and densities and water needs, their response to increasing water availability will be spatially and temporally heterogenous. The response of vegetation is also influenced by microtopography and watering style. This paper discusses strategies for the protection and restoration of the degraded vegetation in the lower reaches of the Tarim River and provides information to complement ongoing theoretical research into ecological restoration in add or semi-arid ecosystems.展开更多
In a fluid (liquid or gas) at rest, the isobars are horizontal surface. This fluid dynamic balance theorem provides adequate advance to tools and techniques for Water Quality Interpretation. We deal in this paper, wit...In a fluid (liquid or gas) at rest, the isobars are horizontal surface. This fluid dynamic balance theorem provides adequate advance to tools and techniques for Water Quality Interpretation. We deal in this paper, with an effective way of exploiting the familiar communicating containers’ principle. That formally consists on providing water samples from desired depths of rivers, oceans, retention dams, etc. The prevailing limiting factor to achieve this feat is the length of our sampling pipes named Mbane Bathymetric Tube (MBT) designed for this purpose when rivers or retention dams are very deep. Providing drinking water to urban growing populations is a challenge that no government can escape. Therefore, improving the tools and techniques for water quality interpretation is an adequate advance for drinking water managerial techniques because this allows the recovery of contaminated water which abounds on the earth by acquiring appropriate wastewater treatment stations. The aim of the manuscript is to provide a brief theoretical description of our designed sampling equipment to allow everyone who is going to use it to solve in advance problems brought by Archimedes’ pressure force when experiencing the sampling pipes. Archimedes’ pressure force acts mainly when moving the sampling pipes to water lower levels and then opening its protective cover which allows the communication with the supply dam.展开更多
基金Project supported by the National Natural Science Foundation of China (No.30470329,40671036,30600092)"Xibuzhiguang"Project of the Chinese Academy of Sciences (CAS).
文摘Restoration and reconstruction of the degraded Tarim River ecosystem is an important challenge. A goal of an ecological water conveyance project is to protect and restore the natural vegetation in the lower reaches of Tadm River by transferring water from Bosten Lake, through the river channel, to the lower reaches. This study describes the changes in groundwater depth during the water transfer and the respondence of riparian vegetation to alterations in groundwater levels. The results indicate that groundwater depth along the Tarim River channel has a significant spatial-temporal component. Groundwater levels closest to the river channel show the most immediate and pronounced changes as a response to water transfer while those further away respond more slowly, although the observed change appears to be longer in duration. With a rise in the groundwater level, natural vegetation responded with higher growth rates, biomass and biodiversity. These favorable changes show that it is feasible to protect and restore the degraded natural vegetation by raising the groundwater depth. Plant communities are likely to reflect the hysteresis phenomenon, requiting higher water levels to initiate and stimulate desired growth than what may be needed to maintain the plant community. Because different species have different ecologies, including different root depths and densities and water needs, their response to increasing water availability will be spatially and temporally heterogenous. The response of vegetation is also influenced by microtopography and watering style. This paper discusses strategies for the protection and restoration of the degraded vegetation in the lower reaches of the Tarim River and provides information to complement ongoing theoretical research into ecological restoration in add or semi-arid ecosystems.
文摘In a fluid (liquid or gas) at rest, the isobars are horizontal surface. This fluid dynamic balance theorem provides adequate advance to tools and techniques for Water Quality Interpretation. We deal in this paper, with an effective way of exploiting the familiar communicating containers’ principle. That formally consists on providing water samples from desired depths of rivers, oceans, retention dams, etc. The prevailing limiting factor to achieve this feat is the length of our sampling pipes named Mbane Bathymetric Tube (MBT) designed for this purpose when rivers or retention dams are very deep. Providing drinking water to urban growing populations is a challenge that no government can escape. Therefore, improving the tools and techniques for water quality interpretation is an adequate advance for drinking water managerial techniques because this allows the recovery of contaminated water which abounds on the earth by acquiring appropriate wastewater treatment stations. The aim of the manuscript is to provide a brief theoretical description of our designed sampling equipment to allow everyone who is going to use it to solve in advance problems brought by Archimedes’ pressure force when experiencing the sampling pipes. Archimedes’ pressure force acts mainly when moving the sampling pipes to water lower levels and then opening its protective cover which allows the communication with the supply dam.
