C - Conservation Actions
After-LIFE: hydraulic work periodic maintenance continues
The maintenance of the hydraulic manufact has been continuing by the Veneto Region, during the After-LIFE period. On April the 15th, after winter, the cleaning of the grid, installed on the upstream wall of the building to protect the two pipes that make the freshwater to flow from the river Sile to the Lagoon, has brought the freshwater flow up to full capacity. Indeed, the cleaning restored the freshwater flows set by the project that are indispensable for the recreation of the typical saline gradient of the lagoon-transition buffer zone, and for the development of the reedbed and its ecosystem services.
Reed and phanerogam transplants were concluded: nature is following its course
Between the end of 2021 and mid-2022, the reed and aquatic phanerogams transplants were completed in the LIFE Lagoon Refresh’s area. This important phase of the project, which started after completion and commissioning of the hydraulic work and which involved previously trained associations of fishermen and hunters from the northern Venice lagoon in the transplantation of more than 2,500 sods of reeds (Phragmites australis) and about 2000 sods of aquatic plants (Zostera noltei, Ruppia cirrhosa and Z. marina). The reedbed transplants aimed at acceleraing and improving restoration of extensive reed-vegetated intertidal surfaces began in summer of 2020. Reed bed took root better in areas close to the freshwater input with more suitable salinity conditions to its growth. However, in places where the rooting of transplanted sods has been still modest, an improvement is expected in the following years (during the After-LIFE of the project) when salinity conditions will be more suitable for the growth of the reeds in the whole transplantation area. The phanerogam transplants, that began in autumn of 2020, have generally taken root, forming more or less extensive patches which are expected to merge together in the following months to form extensive and well-structured meadows. Experiences gained in LIFE SERESTO project showed that it takes about 3 years to have a good development of seagrass meadows, therefore we will expect, in the next few years, a further development of them.
Reed and phanerogams transplants started again: online the new video on stakeholder involvement
On April 2021, the transplant actions of seagrass and reedbeds in the project area of Life Lagoon Refresh started again. First transplants were carried out during summer 2020, but unfortunately with a little delay on timetable due to COVID lockdowns.
First, reed transplants were carried out on June-July, and then they continued until October 2020 with almost 550 clods being transplanted. Seagrass transplants started in autumn 2020, with almost 330 clods of Zostera marina and Z. noltei.
It was exactly on April 2021, when we intensified our activities of transplants to try tocatch up and accelerate the colonization of the reedbeds and seagrasses in the project area. In April, we transplanted more than 550 clods of reeds, whilst from February to April 2021 about 400 clods of phanerogams were planted. Activities will continue throughout the entire year.
Don’t miss to take a look to the brand new video with interviews of fishermen and fish farmers engaged in transplant actions!
After the practical part of the course, the transplant of reeds and phanerogams started!
Due to the state of emergency in response to the coronavirus crisis, both the practical parts of the course for operators involved in the transplant of reeds and phanerogams (the theoretical part was held in July 2019), and the transplants themselves, planned within the Life Lagoon Refresh project, have been delayed.
The field training was completed in May 2020 while in June-July 2020, the transplanting activities finally began. The company in charge of the project transplanted the first 350 clumps of reeds. The fishermen/hunters involved in the project carried out further transplants of 200 clumps in November 2020, for a total amount of 550 clumps of reeds.
Considering the initial flow rate of fresh water (300 l/s), reedbed transplantations have concentrated along the salt marshes edges near the point of fresh water supply and directly affected by this.
The practical course for hunters and fishermen for phanerogam transplants ended in October 2020 and transplants were held in October and November 2020. Two-hundred and seventy three clumps were transplanted, 202 of Z. marina and 71 of Z. noltei, in addition to 550 rhizomes of Z. marina.
The transplants will continue also in the next vegetative season in order to allow a rapid development of the reeds and to accelerate the recolonization of the area by the aquatic plants. The project foresees a simultaneous progressive increase of the fresh water flow up to 1000 l/s. This will produce a larger area with salinity suitable for reed transplant.
The hydraulic and morphological works are finished: the fresh water is flowing into the Lagoon!
The Life Lagoon Refresh project has achieved an important goal: the connection between the Sile River and the Venice Lagoon has been completed and from May 20th, 2020 the fresh water is flowing from the Sile into the Lagoon.
After several unforeseen events, which slowed down the construction sites, such as the exceptional weather event of November 2019 and the health pandemic of 2020, both the hydraulic and morphological works were finally completed and the fresh water input from the Sile Rivers to the Lagoon is now active. Fresh water flows by gravity within the inlet work, as a function of the difference in water level between the river and the lagoon, with variations that depend on the tidal regime. The first regulation of the sluice gates allows an average flow rate of 300 l/s. To avoid the sudden dispersion of fresh water, modular biodegradables elements were installed in the lagoon in front of the hydraulic work. The fresh water and the altimetric variability produced by the morphological structures will make the lagoon environment suitable for reedbed growing.
The next steps involve the planting of reeds and aquatic phanerogams, thanks to the involvement of hunters and fishermen, assiduous frequenters of the area, previously trained during the course of July 12th, 2019 . The fresh water flow rate will be gradually increased up to a maximum average value of 1000 l/s and a second front of biodegradable structures, that limits the flow of fresh water, will be placed. Monitoring activities will verify the efficiency of the works and the effects on the animal and plant communities on the project area. The conservation actions of the Life Lagoon Refresh aim to counteract the saline gradient loss, mainly due to the diversion of rivers, and to increase the biodiversity of fishes, birds, animals of mobile bottom and plants.
The official opening is postponed for now, waiting for fewer restrictions on the social distance of the period. In the meantime, we invite you to follow our updates on this website or visit the social media channels of the project.
Morphological and hydraulic interventions in the finishing straight
Despite the exceptional climatic events at the end of 2019, construction activities (Conservation Actions C) are ending.
In October, an update was published on the state of progress of the works, describing the construction works. For the morphological part in the Lagoon, the phase of construction of the first extract had in fact begun with the fixing of rows of wooden poles inside which the bags in degradable coconut fibre were housed. They will limit the dispersion of the fresh water and will be used as a substrate for planting reeds. On the other hand, the construction sites for the hydraulic system were being set up to define the site area and prepare the by-pass of the cycle path for the trucks passage for the construction of the fresh water inlet from the Sile River in the Lagoon.
To date, the interventions of morphological reconstruction of the first extract are almost completed: the biodegradable bags were placed in the Lagoon as designed and shortly the transplantation of reeds will begin.
The construction site for the hydraulic works is also on home stretch: the pipes were placed inside the building in the embankment between the Sile River and the Lagoon and the connection is about to be completed.
This phase is extremely crucial for the project as both concrete Actions will lead to the achievement of one of the most important goals of the project: the recreation of the typical transitional environment between lagoon and land now lost in most of the Venice Lagoon. This internal area of the lagoon, in fact, should be characterized by low salinity, while to date the environmental conditions are much more similar to those found at sea, with consequent loss of biodiversity that characterizes these environments.
Hydraulic works and Morphologic reconstruction started
The Life Lagoon Refresh project comes alive. Construction work has begun on Actions C1 “Hydraulic works” and C2 “Interventions for morphological reconstruction” (Conservation Actions C). The construction of the hydraulic system is being prepared with the definition of the site area and the preparation of the by-pass of bicycle line for the trucks passage. The freshwater intake from the Sile river to the Lagoon will be realized through the construction of an outlet channel on the right embankment of the Sile river, a crossing section with two parallel pipes, and a return channel in the lagoon. For the morphological part in the lagoon, in the shallow bottom in front of the freshwater intake area, the phase of construction of the first extract has begun: it consists of the driving of lines of wooden poles inside which the bags in degradable coconut fibre are housed. These structures will limit the dispersion of the fresh water and will be used as a substrate for planting the reed.The term of these works is expected by the end of 2019. Both these Conservation Actions will lead to the achievement of one of the most important objectives of the project: the recreation of the typical ecotonal environment in the transitional zone between mainland and lagoon now lost in most of the Venice Lagoon.