ABSTRACT Mount Diablo State Park exemplifies many other conservation areas where managers balance the dual missions of protecting natural resources while providing public access. Roads and trails that crisscross the park are etched into the geomorphic surface, capturing and redirecting storm runoff, and presenting both a challenge for soil conservation and a consequence of construction and maintenance. We used field mapping, remote sensing, and modeling to assess erosion along the roads and trails in Mount Diablo State Park, which encompasses the headwaters of several urbanized watersheds. The field mapping in 2011 determined that 56% of the assessed roads and trails required either repair or reconstruction to control erosion and that ~67% of the culverts in the park required either repair or replacement. Aerial photography and modeling showed that other erosion (unrelated to roads or trails) preferentially occurred during wet periods, in specific lithologies, and on convergent slopes. Although lithology and climate drive slope-forming geomorphic processes, we found that the road and trail system (1) expanded the stream network with a capillary-like system of rills, (2) catalyzed prolonged erosion, and (3) altered the timing and pattern of sediment yield. In addition to water-driven erosion during wet periods, road and trail surfaces were subject to mechanical and wind erosion during dry periods. Spatially, dry erosion and runoff both conformed with and crossed topographic gradients by following the road and trail network. Road- and trail-induced erosion occurred across a wider range of rock properties and slope geometries than is typical for other erosion. Hence, the roads and trails have expanded the spatial and temporal boundary conditions over which geomorphic processes operate and, due to continual soil disturbance, have accelerated erosion rates. Although road density is a commonly used metric to rank road-related impacts at watershed scales, it misses both spatial variability and the opportunity to identify specific road and trail segments for remediation. We developed a spatially explicit scoring scheme based on actual erosion and the potential for sedimentation of discrete waterbodies. The data were incorporated into the park’s road and trail management plan in 2016.

Abstract Social development and rapid growth in the world's population has followed a remarkable technological development the past hundred years. Revolutions in agriculture and industry, medical innovations and new production technologies, have led to an increased standard of living for a larger part of the Earth's population. Megatrends for future developments are lining up and predictions for the next 40 years are numerous. Most ideas about our future societies imply new and innovative geo-scientific achievements. Towards 2058, we will have virtually surveyed and mapped every corner of the Earth. We will have detailed 3D images of the urbanized areas, and 4D models to assist to make reliable forecasts in a world of increased pressure on the natural resources and changing ecosystems. By 2058 the Green Stone Age is established, and we will use all elements in the periodic system and more rare minerals to support new materials and technological solutions. The major energy supplies will be CO 2 free. The agriculture will be more efficient, distribution and consumption of food will be more rational, and we will harvest from more marine food chains than today. More than 70% of the people on Earth will live in megacities and urban areas. Our cities will become smarter and greener, cars and public transport will be self-driving and autonomous tools using artificial intelligence to automate functions previously performed by humans. Substantial resources will be used to repair damaged ecosystems, and most important, we will use materials and products that have fewer negative consequences for the environment. The 17 UN goals for sustainable development are guidelines into the future, and geological surveys should serve as key instruments in the transformation into smarter and more sustainable societies. We are already on our way providing critical minerals for low carbon energy solutions, marine knowledge for blue growth, plans for green and smarter cities, and advanced digitalization for public services, as shown by examples in this present paper.

Water access, sanitation, and security remain key foci of international aid and development. However, the increasing interconnectedness of hydrologic and social systems can cause water initiatives to have unexpected and cascading effects across geographic scales. This presents new challenges for geoscientists working in water development, as distant and complex socioeconomic and environmental relationships, or “telecouplings,” may significantly influence the outcomes and sustainability of development projects. We explore these emerging concepts through a case study in Ethiopia, which receives over half of its annual budget from foreign development assistance and is currently experiencing rapid population growth and environmental change. Using examples from the literature, we identify water development aid initiatives in rural and urban settings and at local and national scales. We then situate these within the telecoupling framework to reveal underlying social-hydrological relationships. Our results indicate that water development is linking Ethiopia’s hydrology with geographically distant communities and markets and creating new and often unexpected flows of people, material, and capital. These are resulting in cascading impacts and cross-scale feedbacks among urbanization, geopolitics, and the water-food-energy nexus in East Africa. We conclude with a discussion of the strengths, limitations, and potential of the telecoupling framework for geoscientists and development practitioners.

Tehran, the capital of the Islamic Republic of Iran, is a case of unplanned urban development. About 12% of Iranians are Tehran dwellers, and geology plays a major role in their environment. The city is located in northern Iran in the foothills of the Alborz Mountains. Sediments underlying the city are composed of coarse (northern part of Tehran) to very fine (southern part of Tehran) sandstone, siltstone, and mudstone with interbeds of gravels and pebbles in various proportions up to a depth of 1600 m. The early settlers were attracted to the area because there were bountiful springs and kanats (or qanats, an underground channel with vertical access shafts used to transport water from an aquifer under a hill to the surface without the need for pumping). The inharmonious geomorphology has strongly influenced the local climate for Tehran, with northern portions of the city in the humid mountains and southern portions in the desert. As development and expansion of the urban area continue, there will be increasing demand for natural resources and services such as water supply and construction material, land-use changes, increasing pollution, and exposure to geological hazards. In this article, we use surface and subsurface geological data to highlight the geological constraints on sustainable urban growth and management.

We reviewed the current state of waste management practices in Nigeria using examples from different parts of the country. Commonly practiced waste disposal methods in Nigeria, such as burial, open-air burning, and open dumping, were found to be ineffective and detrimental to public health and the environment. It was also shown that waste management cannot be successfully operated as a social service. Rather, the generator of waste must be held responsible. Problems confronting efficient waste management in Nigeria include the proliferation of unplanned settlements, traffic congestion, insecurity, and ignorance. An experimental model being used in Lagos State for the management of wastes may be the solution. Given the rate of population growth, industrialization, and urbanization, forward-looking and effective waste management plans need to be set in motion for the protection of public health. Such plans must involve all stakeholders, including the waste generators, the private sector, the informal sector, and regulatory agencies.