1. Introduction

Indonesian is an island with an approximately 17.508 islands and length of beaches approximately 81.000 km [5]. There are very large biotic and abiotic in coastal resources. Magrove ecosystems are found in intertidal areas where deposition of sediment occurs [11]. The are dominated by trees, shrub, herb, liana, epiphyte, saprophyte and associated organisms occupying environment at the land or sea. The most important coastal natural resources is mangrove forest. The objectives of this research is to reveal the existence of flora around the Banyuputih river, sand beach and magrove ecosystems in Banyuputih district, Situbondo regency. The area of Banyuputih district is 481.670 km² consisting of five villages that have sand beaches, river estuaries. Most of the Banyuputih sub-district is flat land with an altitude of 5–60 m above sea level, flat soil conditions and legosol soil characteristics. Most of the people along the Banyuputih river are inhabited by the Madurese and it can be indicated from their language accent. Diversity in the coastal environment of southern Java consists of mangove forest, coastal forest and coral reef forest [4,6].

The relationship between humans and the utilization of biodiversity (organisms) in the environment they live in is known as ethnobotany activity [4,12]. Local wisdom are human behavior that is passed down from generation to generation through stories or tales that are not written by word of mouth [7,4,12].

Mount Ijen is a volcanic mountain, located between Banyuwangi and Bondowoso districts and has an altitude of 2.386 m above sea level (ASL). The content of sulfur and calcium elements (Sulfur and Calcium) which is brought from the top of Mount Ijen is a problem that can be overcome for health problems of organisms. The people of the coastal area of Situbondo district-Banyuwangi are the environment affected by the disturbance of sulfur elements [13,14]. The research reveals that the diversity of flora is related to the intrusion of Sulfur levels along the Banyuputih river.

2. Materials and Methods

The study was conducted through surveys and direct observations in muara sungai Banyuputih Situbondo-Banyuwangi, in May-October 2020 (Fig. 1). This research methods are collecting the plant materials, drying, mounting, preparation and preservation of plant specimens [1,3,8, 11]. The identification and nomenclature of the listed plants were based on the Flora of Java and Flora Malesiana [3,6]. The methods employed were survey, open-ended interviews, semi-structured and in-depth interviews [4]. Meanwhile, the altitude of the research location was carried out using GPS. In determining the water condition: color and pH of the water in Banyuputih river are using pH paper.

Figure 1. Map of Situbondo Regency (star-study area)

3. Results and Discussion

Banyuputih river environment

Madurese peoples generally engaged in the agricultural sector, rice processing, moor and yards. Therefore, along the Banyuputih river, various cultivated plants are planted such as: tebu (Sacharum officinarum), banana (Musa paradisiaca), mango (Mangifera indica), pete (Parkia speciosa), coconut (Cocos nucifera), cassava (Manihot utilisima), rice (Oryza sativa), corn (Zea mays) etc. (Table 1). The diversity of cultivated plants and wild plants as well as environmental factors such as soil and river flow in the area have an indication that it can reduce the impact of sulfur infiltration, thus contributing to water sources. The smell of sulfur around the Banyuputih neighborhood has decreased compared to the location near Mount Ijen (Wiyono, 2017; personal interview, 2020). Sugarcane cultivation has superior growth with very good sugar content, while irrigation uses Banyuputih river. [2,12] reported local wisdom in customary law is used as the main source in managing river resources.

Table 1. River Banyuputih

Banyuputih river at an altitude of 42 m above sea level (ASL); position S. 07° 45' 06.85"; E. 114° 14' 33.04" has yellow water, pH 4-4-5, slightly sulfuric odor with a pH of 4-4.5 (Fig. 2 A, B). [13] explained that the acidity in Mount Ijen is less than pH 4 which consists of Calcium, SiO2, Aluminum, Fe, SO4 and Potassium [Wiyono, 2017]. The diversity of plants around the Banyuputih river has an influence on the level of sulfur concentration in its groundwater sources. The depth of groundwater (well) is 12-15 m, but at this time the people around the river are starting to utilize PDAM water sources.

Figure 2. A. Banyuputih river, Daendeles road. B. Research locations for sugarcane cultivation (Sacharum officinarum) and C. Mimba trees (Azadirachta indica). Photo, J. Batoro

The existence of a mangrove environment is also needed to absorb nitrogen (N) and phosphorus (P) waste released for intensive shrimp pond activities in the sand beach area, Banyuputih district, Situbondo regency [9,10]. The type of sea pine plant, cemara laut (Casuarina equisetifolia L.) is a type of immigrant originating from the Australian continent which grows very well (Figure 3). Banongan beach area, Situbondo district, has a height of 12 m above sea level (ASL), position S 07° 42' 30.25"; E.114° 13' 24. 84" is now being developed into a local tourism business with natural beauty and sunrise. Banongan beach flora diversity includes mimba trees (Azadirachta indica), kambil (Cocos nucifera) and sea pine (Casuarina equisetifolia L.) etc. (Table 2). The major magrove flora commonly find and the estuary Banyuputih for example api-api (Avicenia spp.), bakau (Rhizopora spp.), kerinyu, telekan (Lantana camara), grass etc. (Table 3). Canavalia maritima endemic to the coatal dunes located, on sandy beaches in the southern region of the the island of Java [5]. This type has not been found, maybe the location is less extensive. [11] reported magrove diversity in Papua New Guinea more than 37 species. In the other hand over 50 plant species found in mangrove vegetation in Thailand [6]. The existence of the diversity of coastal plants and mangroves serves as a barrier to intrusion of sea water, wind and tsunami.

Table 2. Sand beach

Table 3. Mangrove area

Figure 3. Sand beach in river autfall Banyuputih Banongan, Situbondo district. A. Distribution Ipomoe pescaprae, mimba (Azadirachta indica), Cocos nucifera and cemara laut (Casuarina equisetifolia L.)

4. Conclutions

Species diversity was recorded around Banyuputih river, Banyuputih sub-district covering 26 families (60 species), mangroves 11 families (13 species) and Banongan sand beach 8 families (11 species). Sugarcane, tebu (Sacharum officinarum) cultivation has superior growth with very good sugar content, while irrigation uses Banyuputih river. The research reveals that the diversity of flora is related to the intrusion of Sulfur levels along the Banyuputih river. The existence of the diversity of coastal plants and mangroves serves as a barrier to intrusion of sea water, wind and tsunami.

ACKNOKLEDGEMENTS

The author would like to express their gratitude to Deparment Physics and Department Biology FMIPA Brawijaya University financial (Doctoral grant program) supports during our research. The author would like thank to dean LPPM, Dr. Bambang Susilo MP, and also Mr. Arifin, thesis students, Mr. Purnomo (laboratory assistant) and Fauzan photos collection for using specimen during this research.