Correction of Soil Acidity in an Organic System of Shadowed Coffee

Through sustainable agriculture it is possible to explore the coffee culture in consortium with native forests in more rugged reliefs, as coffee is a permanent crop in addition to the climatic conditions offered by the swamps that favor its development. Given the above, the present work proposes, based on the acidity results, to quantify the need for correctives in the soil to obtain a better nutritional use offered by agroforestry cultivation of organic coffee in the shade with favorable results to increase productivity and, consequently, the farmer's profit. The research was carried out at the Várzea da Onça farm, in the Yaguara Ecological Complex, located in the municipality of Taquaritinga do Norte, Borborema plateau, in the Agreste Pernambuco mesoregion. Altitude, it is necessary to adopt appropriate management techniques that guarantee production, soil conservation and biodiversity, proposing soil correction to guarantee the ideal nutritional conditions for coffee growth. For this purpose, soil samples were collected in the Top (T), Hillside (E) and Pedimento (P) ranges at depths of 0-20, 20-40 and 40-60 cm when planting shaded coffee and soil samples from Native Forest (MN) preserved and legally protected from the Brejo de Taquaritinga. Active, exchangeable and potential acidity were analyzed, as well as the sum of bases, the potential and effective cation exchange capacity, base saturation and aluminum saturation. The results obtained were subjected to analysis of variance and the means were tested at 5% by the Tukey test. A potential of the system was found with low to very low natural fertility, with a strongly acidic reaction. Thus, adequate soil management and correction techniques are necessary for the crop to absorb all the nutrients made available by the organic matter present on the surface, concluding that all slopes require liming, the slope of Hillside and Mata Nativa they also need plastering for the culture to develop properly.

CHARACTERISTICS OF PHYTOPLANKTON DEVELOPMENT IN MIDDLE CASPIAN IN SUMMER PERIOD

The article highlights the quantitative and qualitative characteristics of phytoplankton organisms in the water area of the Middle Caspian Sea studied by sections: the city of Makhachkala-cape Sagyndyk, the city of Derbent - cape Sandy, Divichi village - Kenderli bay in 2019-2020. The saprobity index and the corresponding saprobity zone of the studied areas have been determined. It has been found that the dominant group was presented by diatoms (43% of the total com-position). The subdominants were dinophytic algae. The basis of the ecological complex of 2019-2020 was made up of representatives of freshwater groups of algae. Only on the section of Divichi village - Kenderli bay there dominated the species of marine origin. Quantitative indicators of phy-toplankton, both in the Middle Caspian as a whole and by sections, in 2020 decreased compared to the previous year. The general part of the biomass was formed by a large diatom Pseudosolenia calcar-avis and representatives of the group of dinophytic algae. The leading role in the abundance figures of the Middle Caspian in 2020 was played by small-cell phytoplankton, mainly from diatoms - Thalassiosira hustedtii, Thalassionema nitzschioides, Aulacoseira granulate, species of the genus Fragilaria. The highest quantitative indicators of 2020 were noted in the section of the city of Makhachkala-cape Sagyndyk in the productive layer of 0-25 m. In 2019-2020, the saprobiological state of the waters of the Middle Caspian was characterized as moderately polluted

Measurement of Coordinated and Coupled Development and Evaluation of Sustainable Development for Marine Economic-Ecological Complex System

The development of marine economy has stimulated the need for marine natural products and services, as well as the demand and utilization intensity of marine resources. As a result, the coastal regions start to discharge more and more pollutants, posing a serious threat to marine ecoenvironment. Because of the interactions between marine economy and marine ecology, it is of practical significance to study the marine economic-ecological complex system (MEECS). However, the relevant studies have several common defects: the incomplete data statistics system, the limited attention on development law or action mechanism, and the lack of long-term quantitative and empirical analysis. To overcome these defects, this paper tries to measure the coordinated and coupled development (CCD) and evaluate the sustainable development of MEECS. Specifically, an ecology-dominated coordinated development model was proposed for the complex system, and a differential equation model was established to describe the dynamic coordinated development of the complex system. Through data envelopment analysis (DEA), the sustainable development of the complex system was evaluated based on its input-output efficiency. Through experiments, the outputs of decision-making units (DMUs) of our model were obtained, and the development of the subsystems in MEECS was evaluated comprehensively to verify the effectiveness of our algorithm.

Structure of waterbird assemblages in fragmented coastal wetlands of Northeastern Algeria

This study was carried out from 2007-2017 at the ecological complex of the Jijel wetlands in the north-east of Algeria. Censuses were conducted during the twelve months of each year to study variation in richness and abundance of waterbird populations for each season. We used distance sampling (point count and transect methods). A total of sixty species (eleven orders and sixteen families) were recorded. The Anatidae and Scolopacidae families were the most numerous with thirteen species. The common coot (Fulica atra), and the Mallard (Anas platyrhynchos) were the most abundant and frequent species each year. About 70 % of the species recorded occur as migrants, passing between the western Palearctic and their winter quarters in North Africa. Phenologically, we found 15 % were breeders, and from the point of view conservation status, 56 % were rare, 40 % were protected by Algerian regulations and 8 % were threatened species listed in the Red List of the International Union for Conservation of Nature (IUCN). Our results of ornithological monitoring in the wetlands in Algeria show that action is needed to address the consequences between birds, human activities, and climate change.

Structure of waterbird assemblages in fragmented coastal wetlands of Northeastern Algeria

This study was carried out from 2007-2017 at the ecological complex of the Jijel wetlands in the north-east of Algeria. Censuses were conducted during the twelve months of each year to study variation in richness and abundance of waterbird populations for each season. We used distance sampling (point count and transect methods). A total of sixty species (eleven orders and sixteen families) were recorded. The Anatidae and Scolopacidae families were the most numerous with thirteen species. The common coot (Fulica atra), and the Mallard (Anas platyrhynchos) were the most abundant and frequent species each year. About 70 % of the species recorded occur as migrants, passing between the western Palearctic and their winter quarters in North Africa. Phenologically, we found 15 % were breeders, and from the point of view conservation status, 56 % were rare, 40 % were protected by Algerian regulations and 8 % were threatened species listed in the Red List of the International Union for Conservation of Nature (IUCN). Our results of ornithological monitoring in the wetlands in Algeria show that action is needed to address the consequences between birds, human activities, and climate change. Data published through GBIF (Doi:10.15470/oud0fp)