# Internet of Things in Marine Environment Monitoring: A Review
## 3 A Review of Existing Marine Environment Monitoring Projects and Systems
\begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline
**Reference** & **Country** & **Sensing Parameters** & **Comm. Protocols** & **Bovy** & **Energy Harvesting** & **Key Features (including Testing and Deployment)** \\ \hline \multicolumn{8}{c}{**Application Area Fish Farm Monitoring**} \\ \hline [PERSON] et al. [63] & Spain & T and pH & ZigBee &? & No & A sub-layer-based power consumption algorithm; tested in a pool \\ \hline [PERSON] et al. [64] & China & Water T, pH value, salinity, DO & GPRS &? & Solar & Multi-hop communication protocol, multiple nodes, and SMT; used in an aquatic experiment have \\ \hline [PERSON] et al. [65] & France & T, depth, salinity, position, cables & GPRS & Vessels & No & Fixed on fishing sparse, self-powered, autonomous- tested in Bay of Discovery \\ \hline [PERSON] et al. [66] & Spain & Sediment depositions & Acoustic & Bovy &? & Ultrasonic sensor; speed through simulations \\ \hline [PERSON] et al. [67] & India & Sea surface T, quality of sea water pH, chlorophyll & WiFi & Fishing vessels & No & A multi-level F2P infrastructure network—OceanNet protocol performance comparison of CoAP, AMOP and MQFT \\ \hline [PERSON] et al. [68] & Spain & Amount of pollution & 7 & Bovy &? & A group-based underwater WSN for monitoring fecal waste and uneven feed, tested on OPNET Model network simulator \\ \hline \multicolumn{8}{c}{**Application Area Wave and current monitoring**} \\ \hline [PERSON] et al. [69] & Philippines & Acceleration, angle & ZigBee, & ZigBee, & Bovy & Solar & Integrated different wave sensors; threshold values generated based on statistics tested in Mariliu Bay \\ \hline [PERSON] et al. [70] & China & Current velocities & 7 &? & No & A temporal evolution model to describe the ocean current process based on the temporal correlation of the current velocity. \\ \hline \multicolumn{8}{c}{Notes: “T”: Temperature; “P”: Pressure; “DO”: Dissolved Oxygen; “COD”: Chemical Oxygen Demand; “No” under Energy Harvesting. Battery power is used; “?”: Related information is not available from the source.} \\ \hline \hline \end{tabular}
\end{table} 
Table 1: _Conf._From this long list of systems, we can see that most of the efforts are related to general ocean sensing and monitoring [34; 35; 36; 37; 38; 39; 40; 41; 42; 43; 44; 45; 46; 47; 48] and water quality monitoring [53; 54; 55; 56; 57; 58; 59; 60; 62]. Some specific efforts have been made for fish farm monitoring [63; 65; 66; 68], coral reef monitoring [61; 62], wave and current monitoring [69], and marine shellfish monitoring [64]. Several projects focus on specific technologies or devices, e.g., buoys [35; 36; 44; 45; 47; 64], energy saving and harvesting [34; 40; 43; 44; 45; 55; 59; 63; 64], routing protocols [46; 64], data transmitting approaches [38; 46; 47], and data analysis [62]. It can also be found that testing places are different among these systems. About half of the developed systems have been tested or deployed in real marine or river environments [34; 35; 37; 39; 40; 41; 42; 43; 44; 45; 55; 56; 57; 60; 61; 65; 69]; a number of them were experimented in lab settings or indoor environments [38; 53; 64; 68]; some were tested in outdoor pools or small ponds/lakes [36; 54; 59; 63]; and several of them were only tested through simulations [38; 66; 68]. It is very interesting to note that most projects, systems, and applications have been developed by research groups in a small number of countries, including China [37; 41; 42; 58; 64], USA [36; 53; 54; 61], Spain [38; 45; 63; 68], UK [46], Indonesia [62], Philippines [69], India [48], Portugal [47], France [65], and Ireland [55; 56]. In these completed systems, most of them occurred on water surfaces [34; 35; 37; 39; 40; 41; 42; 43; 44; 45; 46; 48; 49; 54; 56; 68; 69] and only a few of them were deployed under water [38; 47; 53; 66]. Please note that underwater wireless sensor network is not the focus of this paper and we will briefly discuss this later in the paper.