Hasil untuk "Land use"

Xiao‐peng Song, M. Hansen, S. Stehman et al.

W. Jetz, D. Wilcove, A. Dobson

Over the past few decades, land-use and climate change have led to substantial range contractions and species extinctions. Even more dramatic changes to global land cover are projected for this century. We used the Millennium Ecosystem Assessment scenarios to evaluate the exposure of all 8,750 land bird species to projected land-cover changes due to climate and land-use change. For this first baseline assessment, we assumed stationary geographic ranges that may overestimate actual losses in geographic range. Even under environmentally benign scenarios, at least 400 species are projected to suffer >50% range reductions by the year 2050 (over 900 by the year 2100). Although expected climate change effects at high latitudes are significant, species most at risk are predominantly narrow-ranged and endemic to the tropics, where projected range contractions are driven by anthropogenic land conversions. Most of these species are currently not recognized as imperiled. The causes, magnitude and geographic patterns of potential range loss vary across socioeconomic scenarios, but all scenarios (even the most environmentally benign ones) result in large declines of many species. Whereas climate change will severely affect biodiversity, in the near future, land-use change in tropical countries may lead to yet greater species loss. A vastly expanded reserve network in the tropics, coupled with more ambitious goals to reduce climate change, will be needed to minimize global extinctions.

D. Foster, F. Swanson, J. Aber et al.

J. Penman, Michael Gytarsky, Taka Hiraishi et al.

R. Houghton

R. Kirwan

R. Kitamura, P. Mokhtarian, L. Laidet

K. K. Goldewijk

R. Pielke, A. Pitman, D. Niyogi et al.

J. Goldstein, G. Caldarone, T. Duarte et al.

Jan Weinzettel, E. Hertwich, G. Peters et al.

Increasing affluence is often postulated as a main driver for the human footprint on biologically productive areas, identified among the main causes of biodiversity loss, but causal relationships are obscured by international trade. Here, we trace the use of land and ocean area through international supply chains to final consumption, modeling agricultural, food, and forestry products on a high level of resolution while also including the land requirements of manufactured goods and services. In 2004, high-income countries required more biologically productive land per capita than low-income countries, but this connection could only be identified when land used to produce internationally traded products was taken into account, because higher-income countries tend to displace a larger fraction of land use. The equivalent land and ocean area footprint of nations increased by a third for each doubling of income, with all variables analyzed on a per capita basis. This increase came largely from imports, which increased proportionally to income. Export depended mostly on the capacity of countries to produce useful biomass, the biocapacity. Our analysis clearly shows that countries with a high biocapacity per capita tend to spare more land for nature. Biocapacity per capita can be increased through more intensive production or by reducing population density. The net displacement of land use from high-income to low-income countries amounted to 6% of the global land demand, even though high-income countries had more land available per capita than low-income countries. In particular, Europe and Japan placed high pressure on ecosystems in lower-income countries.

P. Meyfroidt, E. Lambin, K. Erb et al.

H. Akıncı, A. Y. Özalp, B. Turgut

C. Lauber, Kelly S. Ramirez, Z. Aanderud et al.

R. Cervero

The mobility challenges of the developing world are considerably different than those in wealthier, advanced countries, and so are the challenges of coordinating transportation and land use. Rapid population growth, poverty and income disparities, overcrowded urban cores, poorly designed road networks, spatial mismatches between housing and jobs, deteriorating environmental conditions, and economic losses from extreme traffic by congestion are among the more vexing challenges faced by developing cities that could be assuaged through improved coordination of transportation and urban development. This is underscored by examples reviewed in this paper from South Asia, Southeast Asia, China, India, Africa, and South America. It is concluded that whatever is done to improve transportation and land-use integration must be pro-poor. The cardinal features of integrated and sustainable transport and urbanism everywhere---accessible urban activities and safe, attractive walking and cycling environs---are particularly vital to the welfare and prosperity of urbanites in the world's poorest countries.

S. Ong, C. Campbell, P. Denholm et al.

T. Baker, S. Miller

محمدرضا سرتیپی اصفهانی

نطنز یکی از قدیمی‌ترین زیستگاه‌های کویری ایران، شهری با سازمان فضایی مبتنی‌بر باغ‌شهر بوده که به‌دلایل مختلفی ازجمله دورافتادن از آزادراه جدید شرق اصفهان، خشکسالی، تغییرات اقلیمی و توسعة صنعتی غیرمکانمند مبتنی‌بر سود اقتصادی صرف، رونق خود را از دست داده است. این پژوهش قصد دارد با روش مطالعة اسناد کتابخانه‌ای و بهره‌مندی از بازدید میدانی و مصاحبة آزاد با کارشناسان، شهروندان و مدیران شهری، دلیل ناسازگاری توسعه با بستر میزبان آن را بررسی کند. یافتة حاصل نشان می‌دهد در صورتی می‌توان توسعة صنعتی پایدار و متوازن داشت که به تطبیق مقیاسِ توسعة صنعتی با مقیاس پتانسیل‌ها و ظرفیت‌های بستر آن، اعم از ظرفیت‌های کالبدی-مادی بستر و هم ظرفیت اذهان جامعة محلی در پذیرابودن توسعه، به‌عنوان یکی از ارکان اصلی توسعة مکانمند توجه ویژه شود، در غیر این صورت توسعة زیان‌های جبران ناپذیری به بستر خود خواهد زد. آن‌چه در نطنز باعث تخریب باغات و به‌تبع آن سازمان فضایی مبتنی‌بر ساختار باغ‌شهری آن شد.

Hussein A. Kazem, Miqdam T. Chaichan, Ali H.A. Al-Waeli et al.

Integrating the photovoltaic/thermal (PV/T) system in green hydrogen production is an improvement in sustainable energy technologies. In PV/T systems, solar energy is converted into electricity and thermal energy simultaneously using hot water or air together with electricity. This dual use saves a significant amount of energy and officially fights greenhouse gases. Different cooling techniques have been proposed in the literature for improving the overall performance of the PV/T systems; employing different types of agents including nanofluids and phase change materials. Hydrogen is the lightest and most abundant element in the universe and has later turned into a flexible energy carrier for transportation and other industrial applications. Issues, including the processes of Hydrogen manufacturing, preservation as well as some risks act as barriers. This paper provides an analysis of several recent publications on the efficiency of using PV/T technology in the process of green hydrogen production and indicates the potential for its increased efficiency as compared to conventional systems that rely on fossil fuels. Due to the effective integration of solar energy, the PV/T system can play an important role in the reduction of the levelized cost of hydrogen (LCOH) and hence play an important part in reducing the economic calculations of the decarbonized energy system.

Marc Hoyois, Markus Land

We construct a non-$\mathbb{A}^1$-invariant motivic ring spectrum $\mathrm{KO}$ over $\mathrm{Spec}(\mathbb{Z})$, whose associated cohomology theory on qcqs derived schemes is the Grothendieck-Witt theory of classical symmetric forms (as opposed to homotopy symmetric forms). In particular, we show that this theory satisfies Nisnevich descent, smooth blowup excision, a projective bundle formula, and is locally left Kan extended from smooth $\mathbb{Z}$-schemes up to Bass delooping. More generally, our construction produces $\mathrm{KO}$-modules representing localizing invariants of two different families of Poincaré structures on derived schemes, which we call "classical" and "genuine"; the latter Poincaré structures are defined for spectral schemes with involution, but the former only for derived schemes. We then establish basic properties of these motivic spectra. As in $\mathbb{A}^1$-homotopy theory, the fracture square of $\mathrm{KO}$ with respect to the Hopf element recovers the fundamental cartesian square relating GW-theory, L-theory, and K-theory. A new phenomenon when $2$ is not a unit is that $\mathrm{KO}$ is not Bott-periodic, and the left and right Bott periodizations of $\mathrm{KO}$ represent the Grothendieck-Witt theories of homotopy symmetric and homotopy quadratic forms, respectively. We also construct the expected metalinear $\mathrm{E}_\infty$-orientation of $\mathrm{KO}$. Finally, we show that the $\mathbb{A}^1$-localization of $\mathrm{KO}$ recovers the motivic spectrum recently constructed by Calmès, Harpaz, and Nardin.