Effects of Breccia and Water Contents on the Mechanical Properties of Fault-core-zone Materials: an Experimental Investigation Using Artificial Specimens

Determining the mechanical properties of fault-core-zone materials is challenging because of the low strength of such materials, which affects field sampling, specimen preparation, and laboratory testing. We overcame this problem by preparing and testing mechanical properties of 132 artificial fault-core-zone specimens consisting of mixtures of breccia, sand, clay, and water. The unconfined compressive strength (UCS), elastic modulus (E), and penetration resistance value (PRV) of these fault-core-zone materials were measured, and the effects of breccia content and water content on mechanical properties were assessed. Results show that UCS is inversely proportional to breccia content and water content, and that E is inversely proportional to water content. Furthermore, the inverse relationship of UCS with water content varies with breccia content. UCS is proportional to both PRV and E, and the relationship for each varies with breccia content. High coefficients of determination (R2 = 0.62–0.88) between the parameters suggest that breccia content, water content, and PRV are potentially useful parameters for estimating the mechanical properties of fault core zones.

Kondisi Terkini Presentase Tutupan Terumbu Pada Masa Pandemi Covid-19 di Gili Air, Taman Wisata Perairan Gili Matra, Nusa Tenggara Barat

Gili Matra Aquatic Tourism Park has two conservation targets, namely biological targets and social, cultural and economic targets. Coral reef ecosystems, apart from being a conservation target, are also an attraction for tourists to visit. This research was conducted to determine the condition of the coral reef ecosystem to be used as the basis for the management of conservation areas. The research was conducted by collecting coral reef data either through surveys or secondary data from the results of previous studies. Coral reef survey using the standard Line Intercept Transect method. The survey results show that the condition of coral reefs in the utilization zone is better than the core zone. Live coral cover in the utilization zone reached 71% so it was categorized as good, while in the core zone it only reached 8% so it was categorized as bad. Coral reefs in the core zone are unable to recover even though the number of tourists has decreased during the Covid-19 pandemic. Therefore, the location of the core zone on Gili Air needs to be evaluated further so that the effectiveness of Gili Matra TWP management can be improved. Key words: coral reefs; Gili Matra; Conservation

Ecological risk assessment of potentially invasive alien plant species in Cibodas Biosphere Reserve, West Java, Indonesia

More than 80 potentially invasive plant species have spread throughout the Cibodas Biosphere Reserve, Indonesia. Recently, research has shown that the surrounding community utilizes more than 50% of these species. Although this utilization provides social and economic benefits, it threatens the Cibodas Biosphere Reserve core zone ecologically. Therefore, this study conducted a risk assessment to determine the invasiveness level of utilized plant species. The evaluation was performed using Hawaii and Pacific Weed Risk Assessment (WRA) scheme. The results show that almost all the potentially invasive plant species are high risk, with scores ranging from 10 to 26, except for Fragaria vesca and Mentha arvensis. The highest WRA score was obtained for Lantana camara and followed by Austroeupatorium inulifolium, Cobaea scandens, Mikania cordata, Sonchus asper, Clidemia hirta, Piper aduncum, Sonchus arvensis, Cestrum aurantiacum, Dracaena fragrans, Passiflora ligularis, Podachaenium eminens, Thunbergia coccinea, and Wedelia trilobata. As most of these species were herbaceous plants obtained from cultivated areas, the risk of invasion into the core zone is low. Based on the findings, the recommended management option to control these species is harvesting, accompanied by containment. Through this method, the community can continue to use the species while controlling the population, thereby limiting their spread.

SECTORAL SPECIAL FEATURES OF TERRITORIAL DEVELOPMENT OF PETERSBURG CITY AGGLOMERATION

The article presents the structure of the St. Petersburg city agglomeration at the present stage of its development: agglomeration core, zone of satellites, planning sectors. The problems and trends, sectoral special features of agglomeration development are described. The author describes the parameters of territorial development of the St. Petersburg city agglomeration, the main characteristics of its structural units: the population size, its density, the proportion of urban and rural population.

The Use of Small Format Air Photos for Mapping Land Cover Changes in Gumuk Pasir Parangtritis Core-Zone, 2015-2019

Gumuk Pasir Parangtritis is one of the potentials of the coastal area of ​​Parangtritis village in Yogyakarta, with several important roles for the coastal ecosystem and its surroundings, such as ecology, disaster, tourism, economy, and aquifer reserves. However, behind this important role, the existence of sandbanks is increasingly threatened from year to year because the area of ​​sand cover continues to decline, especially in the core zone. Therefore, regular and effective mapping and monitoring efforts are needed. This study aims to a) conduct land cover mapping using the Geographic Object Based Image Analysis (GEOBIA) method in the 2015-2019 timeframe; b) analyze changes in land cover in the core zone of sandbanks during 2015-2019; and c) evaluate the results of restoration of sand dune core zone in terms of land cover changes that have occurred until 2019. Small format aerial photographs (FUFK) are the data used in this study while the mapping method used is rule-based classification. The land cover of the sand dune core zone in 2015 included buildings, vegetation, sand, roads and ponds, while in 2019 it was in the form of buildings, vegetation, sand, and roads. Based on the classification results in the two years, it can be seen that there are changes in land cover (including area) through the cross-section of the two classification results. Some of the factors include the number of land use changes, the amount of vegetation, and sand mining. Furthermore, this change can be used as a basis for evaluating the success of the restoration efforts of the Gumuk Pasir Parangtritis core zone to date. The results of the evaluation show that the restoration carried out so far has not had much impact so it can be said that it has not been successful, because the area of ​​sand cover has actually decreased a lot (from 528,680 m2 to 344,347 m2), while the land cover in the form of vegetation and buildings has increased in size (from 869,341 m2 to 1,037,879 m2 for vegetation cover and an area of ​​4,674 m2 to 22,953 m2 for buildings).

Ganxiao Dong: A Hotspot of Cave Biodiversity in Northern Guangxi, China

Located in the core zone of Mulun National Nature Reserve in northern Guangxi, the limestone cave Ganxiao Dong harbours the richest cave fauna currently known in China. In total, 26 species of cave invertebrates have been recognized so far, in spite of limited sampling efforts. Of them, 20 are troglobionts or stygobionts, including one snail, four millipedes, three spiders, one harvestman, three isopods, two springtails, two crickets, one non-glowing sticky worm, and three trechine beetles. Six other species are troglophiles. The most remarkable characteristic of this fauna is its high number of troglomorphic species, especially among millipedes, crickets and beetles.

Structure Partition and Reasonable Width Determination of Waterproof Coal Pillar in Strip Mining

Retaining a waterproof coal pillar is the most effective water conservation method for a roadway close to the gob, and determining a reasonable width of the waterproof coal pillar has been a common problem among mining scholars for a considerably long time. Based on the mining of the 15208 mining face in Xinjing Coal Mine, the structure of waterproof coal pillar is divided into a mine-pressure-influenced plastic zone, an effective waterproof elastic core zone, and a water pressure failure zone. The mine-pressure-influenced plastic zone width is determined by using the limit equilibrium theory, the parabolic strength theory, and the separation variable method. The effective waterproof elastic core zone width is determined by the semi-inverse solution method, and the water pressure failure zone width is determined by considering the infiltration and softening of water. After that, combined with the previous theoretical analysis of engineering examples, the theoretical value of waterproof coal pillar width is obtained. In addition, the physical shape distribution of the waterproof coal pillar is measured by ultrasonic detection technology. The results are consistent with the field measured results. The correctness of the model is verified. Finally, the rationality of the model is verified by comparing with the previous classical models. The research results are applied to the design of the waterproof coal pillar in Xinjing Coal Mine, which could provide a theoretical basis for determining the width of the waterproof coal pillar located close to a gob.

Use of Wild Edible Plants: Can They Meet the Dietary and Nutritional Needs of Indigenous Communities in Central India

Despite significant evidence base on quantifying ecosystem services, the role of biodiversity in supporting such services in diversified landscapes, and how indigenous communities exploit, utilize and manage plant resources in a biocultural regime, remains understudied. This study examines the role of wild edible plants (WEPs) in meeting the food, nutrition and household income of indigenous communities under the biodiversity rich landscape of the Achanakmaar-Amarkantak Biosphere Reserve (AABR—22°15′ to 22°58′ N latitudes and 81°25′ to 82°5′ East longitudes) of Central India. Results revealed remarkable differences among Baiga, Gond, Kol, and Oraon ethnic communities and also location (core, buffer and transition) effect on utilization pattern of wild edibles. A sum total of 172 WEPs comprising 60 vegetables, 70 fruits, seeds and nuts, 23 underground tubers and 19 mushrooms were collected, consumed, and surplus were marketed by the communities. On average, the number of wild edibles collected annually by households were in the following quantities: 40–240 kg leafy vegetables, 125–386 kg flowers, 120–250 kg fruits, 12–125 kg legumes, 24–120 kg tubers, 5–35 kg mushrooms. Among ethnic groups, the Baiga primitive community utilized 70–90% followed by Gonds (58–81%), Kols (52–78%), Oraons (43–79%), and other communities (38–68%) in different zones. WEPs have contributed to 5–24% (Rs 3559- 12,710) of household income, which was highest in the core zone and lowest in the transition zone. It was observed that WEPs were complemented the diets rather than being a substitute for staple foods. They supplied only 3.7–8.3% of energy and 1.1–4.9% protein requirements; however, they significantly supplemented ascorbic acid, thiamine, calcium, and iron by 38.1–73%, 13.7–35.4%, 17.2–29.1%, 2.6–13.5%, respectively. Significantly higher quantities of nutrients were supplemented in the core zone compared to other zones. WEPs were currently underutilized (less intake) especially in buffer and transition zones, complementing the staple foods and partially supplementing the essential macro- and micro-nutrients. However, these have the potential to fulfill the dietary needs and ensure balanced nutrition, if consumed in recommended portions and sizes. The paper discusses policy implications that ensure coherence and coordination of local indigenous communities for conservation and sustainable utilization of WEPs of AABR, Central India.