Responses of Functional Traits of Macrobenthic Communities to Human Activities in Daya Bay (A Subtropical Semi-Enclosed Bay), China

The biological trait analysis (BTA) is regarded as a promising approach to unravel how ecosystem functions respond to human-induced disturbances. This study considered the four sampling locations associated with different human activities in Daya Bay, that is, the domestic and industrial sewage discharge area (SED), mariculture area (MRC), nuclear power plants thermal discharge area (NTD), and an area with relatively low human disturbance as a reference (REF). Thirty modalities of nine traits were selected in BTA. Our results showed a clear shift in the functional structure of macrobenthic communities between the sampling locations, except for the case between NTD and REF. The trait composition in the communities did not highlight any seasonal patterns. Bioturbation, longevity, tolerance, body size, feeding habit, and environmental position were the key traits to characterize the functional structure of macrobenthic communities and demonstrated predictable responses along the environmental gradients. Water depth, DO, Chl-a, NH4+, and petroleum contaminants in sediments were the main variables influencing the trait composition. In addition, the taxonomic index (H′) and functional diversity index (Rao’s Q) showed clear differences among the sampling locations. Although there were no significant differences between NTD and REF in terms of the trait composition and functional diversity, a potential function loss in NTD still can be detected through the integrated analysis with taxonomic diversity. We suggest that the traits (except for fragility, larval development, and living habits) selected and the diversity indices (H′ and Rao’s Q) could serve as promising indicators of ecological conditions in Daya Bay.

POTENSI AIR TANAH DAN TATA GUNA AIR TANAH UNTUK KEBUTUHAN DOMESTIK DI DATARAN ALUVIAL LIMBOTO-GORONTALO PROVINSI GORONTALO

Dataran Aluvial Limboto-Gorontalo merupakan bagian dari wilayah Cekungan Airtanah Gorontalo di Kabupaten Gorontalo dan merupakan wilayah pusat pertumbuhan penduduk, perekonomian dan pembangunan. Dataran aluvial Limboto-Gorontalo merupakan daerah yang dilalui oleh jalur sesar utama Gorontalo dan keterdapatan danau Limboto di dalamnya. Fenomena tersebut mengindikasikan proses geologis yang rumit dan unik, dan secara tidak langsung berpengaruh terhadap kondisi akuifer dan potensi airtanah wilayah setempat Penelitian ini bertujuan untuk mengkaji kondisi akuifer, potensi airtanah bebas, dan zonasi tata guna airtanah beserta rekomendasinya. Metode penelitian yang digunakan adalah metode survey yaitu dengan melakukan pengamatan dan pengukuran langsung dilapangan. Teknik pengambilan sampel yang digunakan adalah sampel acak sistimatik (systimatic random sampling) untuk pengukuran geolistrik dan pengukuran data hidrogeologi lapangan. Analisis data dilakukan dengan menggunakan pendekatan terintegrasi antara geologi, geomorfologi berbasis PJ dan SIG, serta pendekatan geofisika dan hidrogeologi lapangan. Hasil penelitian menunjukkan bahwa: 1) Secara hidrogeologi, lokasi penelitian merupakan wilayah pelepasan (discharge area) sistem CAT Gorontalo, tipologi sistem akuifer dataran alluvial, dengan jenis akuifer terdiri atas lapisan akuifer tidak tertekan, semi tertekan dan tertekan. Karakteristik litologi bawah permukaan lokasi penelitian umumnya menunjukkan silang siur antara material lempung (aquiklud), lempung pasiran dan pasir lempungan (aquitard), pasir dan krikil (aquifer). Jenis litologi penyusun akuifer tidak tertekan terdiri pasir dengan nilai resistivitas 20-150 ohm-meter. Ketebalan akuifer tidak tertekan khususnya di wilayah bagian Barat Danau Limboto teridentifikasi memiliki ketebalan akuifer yang relatif seragam dengan ketebalan rata-rata 5 meter, sedangkan di wilayah bagian Utara dan Selatan cukup bervariasi yaitu dari ketebalan 1,5 meter hingga ketebalan 27,5 meter, 2). Zona potensi airtanah bebas terdiri atas 4 (empat) kategori yaitu zona potensi tinggi dan sangat tinggi, zona potensi sedang, dan zona potensi rendah tersebar di wilayah bagian Utara dan Selatan lokasi penelitian, 3). Zona penurapan airtanah bebas terdiri atas 4 (empat) zona penurapan yaitu zona penurapan I (kelas tinggi) dengan karakteristik potensi airtanah baik dari segi kuantitas dan kualitas, dapat diturap dan dimanfaatkan tanpa faktor pembatas, zona penurapan II (kelas sedang) memiliki potensi airtanah yang cukup baik dari segi kuantitas dan potensi kualitas yang terbatas secara lokal, dapat diturap dan dimanfaatkan dengan pengawasan, dan zona penurapan III (kelas rendah) merupakan zone dengan kuantitas airtanah rendah, dapat diturap dengan sangat terbatas

POTENSI AIR TANAH DAN TATA GUNA AIR TANAH UNTUK KEBUTUHAN DOMESTIK DI DATARAN ALUVIAL LIMBOTO-GORONTALO PROVINSI GORONTALO

Dataran Aluvial Limboto-Gorontalo merupakan bagian dari wilayah Cekungan Airtanah Gorontalo di Kabupaten Gorontalo dan merupakan wilayah pusat pertumbuhan penduduk, perekonomian dan pembangunan. Dataran aluvial Limboto-Gorontalo merupakan daerah yang dilalui oleh jalur sesar utama Gorontalo dan keterdapatan danau Limboto di dalamnya. Fenomena tersebut mengindikasikan proses geologis yang rumit dan unik, dan secara tidak langsung berpengaruh terhadap kondisi akuifer dan potensi airtanah wilayah setempat Penelitian ini bertujuan untuk mengkaji kondisi akuifer, potensi airtanah bebas, dan zonasi tata guna airtanah beserta rekomendasinya. Metode penelitian yang digunakan adalah metode survey yaitu dengan melakukan pengamatan dan pengukuran langsung dilapangan. Teknik pengambilan sampel yang digunakan adalah sampel acak sistimatik (systimatic random sampling) untuk pengukuran geolistrik dan pengukuran data hidrogeologi lapangan. Analisis data dilakukan dengan menggunakan pendekatan terintegrasi antara geologi, geomorfologi berbasis PJ dan SIG, serta pendekatan geofisika dan hidrogeologi lapangan. Hasil penelitian menunjukkan bahwa: 1) Secara hidrogeologi, lokasi penelitian merupakan wilayah pelepasan (discharge area) sistem CAT Gorontalo, tipologi sistem akuifer dataran alluvial, dengan jenis akuifer terdiri atas lapisan akuifer tidak tertekan, semi tertekan dan tertekan. Karakteristik litologi bawah permukaan lokasi penelitian umumnya menunjukkan silang siur antara material lempung (aquiklud), lempung pasiran dan pasir lempungan (aquitard), pasir dan krikil (aquifer). Jenis litologi penyusun akuifer tidak tertekan terdiri pasir dengan nilai resistivitas 20-150 ohm-meter. Ketebalan akuifer tidak tertekan khususnya di wilayah bagian Barat Danau Limboto teridentifikasi memiliki ketebalan akuifer yang relatif seragam dengan ketebalan rata-rata 5 meter, sedangkan di wilayah bagian Utara dan Selatan cukup bervariasi yaitu dari ketebalan 1,5 meter hingga ketebalan 27,5 meter, 2). Zona potensi airtanah bebas terdiri atas 4 (empat) kategori yaitu zona potensi tinggi dan sangat tinggi, zona potensi sedang, dan zona potensi rendah tersebar di wilayah bagian Utara dan Selatan lokasi penelitian, 3). Zona penurapan airtanah bebas terdiri atas 4 (empat) zona penurapan yaitu zona penurapan I (kelas tinggi) dengan karakteristik potensi airtanah baik dari segi kuantitas dan kualitas, dapat diturap dan dimanfaatkan tanpa faktor pembatas, zona penurapan II (kelas sedang) memiliki potensi airtanah yang cukup baik dari segi kuantitas dan potensi kualitas yang terbatas secara lokal, dapat diturap dan dimanfaatkan dengan pengawasan, dan zona penurapan III (kelas rendah) merupakan zone dengan kuantitas airtanah rendah, dapat diturap dengan sangat terbatas.

Aquifer and Pond Relationship Under Potential Influence of Eucalyptus and Sugarcane

A hydraulic interaction between a pond and shallow aquifer in a watershed surrounded by cultivations of sugarcane and eucalyptus trees was evaluated in Brazil. The pond, located in lower topographic levels, was prematurely interpreted as the local shallow aquifer's discharge area, suggesting the groundwater could flow towards the pond. However, water table gradients indicated opposite directions, bringing up questions about the eucalyptus root's potential to access groundwater, consequently lowering the water level and changing the groundwater flow directions. Physicochemical parameters, stable isotopes of δ18O and δ2H, major ions analysis were determined in samples of groundwater and pond water; and geophysical surveys and groundwater level measurements were performed before and after the eucalyptus cutting. The results showed 1) the eucalyptus does not have a significant influence on the groundwater dynamic; 2) the pond behaves as a recharge, not a discharge area; and 3) previously considered as a local flow, the interaction between groundwater and pond is determined by an intermediate flow system, controlled by a near spring, independently of the seasonal variation and land uses.

Experimental Study on the Lateral Seepage Characteristics in the Tension Saturated Zone

To study the lateral seepage field in the tension saturated zone (TSZ), an experiment with no evaporation and precipitation infiltration was carried out in a self-made seepage tank filled up with fine sand. Based on the data and plots obtained, the lateral seepage field distribution features in the TSZ can be divided into three area for discussion: ascending area, descending area, and the nearly horizontal flow area. In the ascending and descending area, the total water potential gradient diminished from the recharge area to the discharge area and the seepage velocity was faster. In the nearly horizontal flow area, the total water potential gradient was lower and the seepage velocity was slower. The pressure potential gradually decreased horizontally from the recharge area to the discharge area, while in the vertical profile, it gradually decreased from the bottom to the top in the whole seepage area. In the absence of evaporation, the vertical water exchange among the saturated zone, TSZ, and unsaturated zone in nearly horizontal flow area is weak. Contrarily, in the ascending area and descending area, vertical water flows through both the phreatic surface and the upper interface of the TSZ. When there is lateral seepage in the TSZ, the thickness of the TSZ generally increases from the ascending area to the nearly horizontal area and then to the descending area. It should be pointed out that in the nearly horizontal area, the TSZ thickness is approximately equal to the height of the water column. Overall, the lateral seepage in the TSZ can be regarded as a stable siphon process, hence the siphon tube model can be further used to depict this lateral seepage.

EFFECTS OF THE REUSE OF UNTREATED WATER FROM THE AVO’O RIVER (CAMEROON) CONTAMINATED BY FECAL SLUDGE FOR THE GROWTH OF SOLANUM NIGRUM L.

Objective: The main objective of this research was to evaluate the growth parameters and sanitary quality of Solanum nigrum L. irrigated with polluted water from Avo’o river in Nomayos. Methods: Faecal sludge, water from Avo’o River and Solanum nigrum L., were analysed with respect to microbiological and parasitological parameters. Four points (S0: Control site, located in Mbankomo at 3 km away from faecal sludge discharge area; S1: located at 810 m before the faecal sludge discharge area; S2: located at 100 m away from the faecal sludge discharge area; and S3: located at 350 m after the faecal sludge discharge area) were considered for sampling events. For faecal indicator (FC: Faecal coliforms and FS: Faecal Streptococci), the membrane filtration method was used. Helminthes eggs were determined using the method of Bailenger, modified by Rodier. The growth parameters of S. nigrum L., measured in different site mentioned above, were plant height, number, length and width of fresh leaves. Results: High concentration of FC (6857 ± 5180) and FS (2500 ± 1876 CFU/100 ml), as well as helminths eggs (273 ± 186 eggs/L) were obtained in Avo’o water samples. The strong correlations (r=0.9) clearly show that the waters of the Avo’o stream influence the growth of S. nigrum L. Conclusion: Despite the best growth of Solanum Nigrum L. irrigated with water from Avo’o River, high concentration of parasites was obtained on their leaves (43 eggs/100 g) highlight the necessity of a better management of faecal sludge in this city.

The Three Domains of Life Within the Discharge Area of a Shallow Subterranean Estuary at a High Energy Beach

Subterranean estuaries (STEs) play an important role in linking nutrient cycling between marine and terrestrial systems. As being the primary drivers of nutrient cycling, the composition of microbial communities and their adaptation toward both, terrestrial and marine conditions are of special interest. While bacterial communities of STEs have received increasing scientific attention, archaeal and meiofaunal diversity was mostly neglected. Previous studies at the investigated sampling site, the STE of a mesotidal beach at the German North Sea island of Spiekeroog, focused on spatial and seasonal patterns of geochemical and bacterial diversity. By additionally investigating the archaeal and meiofaunal diversity and distribution, we now aimed to fill this gap of knowledge to understand the microbial response to submarine groundwater discharge (SGD). The topography of Spiekeroog beach and associated geochemical gradients in porewater displayed a distinct cross-shore zonation, with seawater infiltration on the upper beach at the high water line (HWL), and saline and brackish porewater exfiltration (SGD) at the ridge-runnel structure and the low water line (LWL) on the lower beach. This led to a higher evenness of prokaryotic communities in lower beach areas impacted by SGD compared to unimpacted areas. Archaea contributed 1–4% to the 16S rRNA gene sequence dataset. Those were dominated by Nitrosopumilaceae, corresponding well to higher concentrations of NH4+ in the discharge area of the STE. The unimpacted sites had elevated abundances of Wosearchaeia, which were also detected previously in impacted areas of an STE at Mobile Bay (Gulf of Mexico). While a large proportion of prokaryotes were present in the entire intertidal area, meiofaunal community compositions were site specific and dominated by nematodes. Nematode communities of the high-water line differed distinctively from the other sites. Overall, our data indicates that the three domains of life display distinctly different adaptations when facing the same conditions within the STE. Therefore, distribution patterns of any domain can only be understood if all of them, together with basic environmental information are investigated in an integrated context.