Afforestation is a main tool for preventing desertification and soil erosion in arid and semiarid regions of Iran. Large-scale afforestation, however, has poorly understood consequences for the future ecosystems in the term of ecosystems protection. The objective of the present study is to identify changes in soil properties following different intervals of planting of Ailanthus altissima (tree of heaven) in semiarid afforestation of Iran (Chitgar Forest Park, Tehran). For this purpose, sand, silt and clay ratios, bulk density, soil moisture, pH, electrical conductivity, phosphorus, potassium, magnesium, calcium, sodium, total soil N, and total carbon was measured. Our study highlighted the potential of the invasive trees by A. altissima, to alter soil properties along chronosequence. Almost all soil quality attributes showed a declining trend with stand age. A continuous decline in soil quality indicated that the present land management may not be sustainable. Therefore, an improved management practice is imperative to sustain soil quality and maintain long-term productivity of plantation forests. Thinning activity will be required to reduce the number of trees competing for the same nutrients especially in a older stand to protect forest soils.

Small watershed ecological compensation is an important economic means to solve the contradiction between protecting the ecological environment and developing the economy. Taking the Changtian small watershed in the Xixiu District of Anshun City as an example, this paper uses the ecological service function value method to roughly calculate the ecological service function value of the small watershed ecosystem: the ecological service function value of the Changtian small watershed is 913.586 million yuan, and the total amount of ecological compensation is 11.6245 million yuan, of which the farmland system compensation is 1.3194 million yuan, the forest system compensation is 7.5336 million yuan, and the water system compensation is 256,000 yuan, The compensation for the fruit forest system is 2,515,500 yuan. Based on the value of ecosystem service function, the compensated and non-compensated ecosystem service functions are distinguished, and the equivalent factors that different ecosystems can provide compensated ecosystem functions are expressed, so that the determination of ecological compensation amount is scientific and more accurate, and then provides a basis for the determination of ecological compensation standard of the small watershed.

This paper argues for a novel approach to financing infrastructure needs in Arab countries. It first describes the context of rising public debt in the region, contrasting it with the vast infrastructure needs. It then discusses the challenges in meeting these needs with traditional financing. The paper then makes the case for maximizing finance for development by using public-private partnerships and presents a few successful examples in Arab countries. Finally, the paper explores the way forward and concludes on the need for strong state capacity and integrity to promote the “maximizing finance for development” approach.

Despite Cameroon’s immense sand reserves, several enterprises continue to import standardized sands to investigate the properties of concretes and mortars and to guarantee the durability of built structures. The present work not only falls within the scope of import substitution but also aims to characterize and improve the properties of local sand (Sanaga) and compare them with those of imported standardized sand widely used in laboratories. Sanaga sand was treated with HCl and then characterized in the laboratory. The constituent minerals of Sanaga sand are quartz, albite, biotite, and kaolinite. The silica content (SiO₂) of this untreated sand is 93.48 wt.%. After treatment, it rose 97.5 wt.% for 0.5 M and 97.3 wt.% for 1 M HCl concentration. The sand is clean (ES, 97.67%–98.87%), with fineness moduli of 2.45, 2.48, and 2.63 for untreated sand and sand treated with HCl concentrations of 0.5 and 1 M respectively. The mechanical strengths (39.59–42.4 MPa) obtained on mortars made with untreated Sanaga sand are unsatisfactory compared with those obtained on mortars made with standardized sand and with the expected strengths. The HCl treatment used in this study significantly improved these strengths (41.12–52.36 MPa), resulting in strength deficiencies of less than 10% after 28 curing days compared with expected values. Thus, the treatment of Sanaga sand with a 0.5 M HCl concentration offers better results for use as standardized sand.

The debate on relocating Indonesia's national capital from Jakarta stems from critical issues such as overpopulation, social inequality, environmental degradation, and natural disaster risks. These challenges highlight the need to reassess Jakarta's viability as the nation's administrative center. This study evaluates Indonesia's readiness to address the complexities of relocation by analyzing Jakarta's socio-economic, political, cultural, and geographical conditions. Using a systematic literature review (SLR) with a qualitative approach, the research explores key questions: Do Jakarta's conditions necessitate relocation? What challenges might arise from the move? How prepared is Indonesia to tackle these challenges? The SLR process includes defining questions, sourcing literature from reputable databases, applying inclusion/exclusion criteria, and synthesizing data for analysis. Findings reveal Jakarta's multifaceted challenges, including social disparities, environmental degradation, disaster risks, and governance issues, which emphasize the urgency of considering relocation. However, the study also identifies significant hurdles, such as high costs, logistical complexities, potential social conflicts, and environmental risks at the new capital site. Relocating the capital is a strategic and complex undertaking that requires meticulous planning. Indonesia must weigh Jakarta's current issues, address potential relocation challenges, and ensure readiness for risk mitigation and sustainable development. Comprehensive and thoughtful planning is essential to achieve a successful and balanced transition.