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Ficus is a multi-purpose pan-tropical genus of woody plants proven to be keystone resources for populations and animals. In Africa, the genus is well-represented, but the lack of summed-up information prevents its valorization and implementation of conservation strategies. This study aims to summarize documented knowledge on the Ficus genus in Africa and propose perspectives for future research focusing on the aforementioned issues. 215 publications published between 1980 and 2023 were obtained from electronic databases and general web searches. They were critically assessed for information on its geographical distribution, diversity, threats and uses. The genus Ficus comprises 116 species in Africa. The highest diversities were found in the tropical zone countries, mainly in Cameroon, Congo, Central Africa Republic, Gabon, and Uganda. Ficus species are used mostly as medicine and food. The most used species in medicine were F. carica, F. exasperata, F. sur, F. sycomorus, and F. thonningii. For food, the most utilized species were F. carica, F. platyphylla, F. sur, F. sycomorus, and F. thonningii. Ficus sycomorus was the most useful species according to the relative importance, respectively followed by F. exasperata, F. sur, F. thonningii, and F. platyphylla. Habitat loss driven by agricultural practices is probably the biggest threat to the genus Ficus in Africa, to which is added unsustainable practices such as overexploitation and cutting of vital organs for medicine. Moreover, 14 African F. species are on the list of threatened species in the red list of IUCN. Despite these threats, no conservation strategy is taken towards the genus Ficus in Africa. It becomes urgent to take conservation measures to ensure the long-term viability of this keystone genus. That would require an integrated and collaborative approach involving both local communities and environmental management authorities. [ABSTRACT FROM AUTHOR]

Many agricultural watersheds rely on the voluntary use of management practices (MPs) to reduce nonpoint source nutrient and sediment loads; however, the water‐quality effects of MPs are uncertain. We interpreted water‐quality responses from as early as 1985 through 2020 in three agricultural Chesapeake Bay watersheds that were prioritized for MP implementation, namely, the Smith Creek (Virginia), Upper Chester River (Maryland), and Conewago Creek (Pennsylvania) watersheds. We synthesized patterns in MPs, climate, land use, and nutrient inputs to better understand factors affecting nutrient and sediment loads. Relations between MPs and expected water‐quality improvements were not consistently identifiable. The number of MPs increased in all watersheds since the early 2010s, but most monitored nutrient and sediment loads did not decrease. Nutrient and sediment loads increased or remained stable in Smith Creek and the Upper Chester River. Sediment loads and some nutrient loads decreased in Conewago Creek. In Smith Creek, a 36‐year time‐series model suggests that changes in manure affected flow‐normalized total nitrogen loads. We hypothesize that increases in nutrient applications may overshadow some expected MP effects. MPs might have stemmed further water‐quality degradation, but improvements in nutrient loads may rely on reducing manure and fertilizer applications. Our results highlight the importance of assessing MP performance with long‐term monitoring‐based studies. [ABSTRACT FROM AUTHOR]

Targeted conservation approaches seek to focus resources on areas where they can deliver the greatest benefits and are recognized as key to reducing nonpoint source nutrients from agricultural landscapes into sensitive receiving waters. Moreover, there is growing recognition of the importance and complementarity of in-field and edge-of-field conservation for reaching nutrient reduction goals. Here we provide a generic prioritization that can help with spatial targeting and applied it across the conterminous US (CONUS). The prioritization begins with identifying areas with high agricultural nutrient surplus, i.e., where the most nitrogen (N) and/or phosphorus (P) inputs are left on the landscape after crop harvest. Subwatersheds with high surplus included 52% and 50% of CONUS subwatersheds for N and P, respectively, and were located predominantly in the Midwest for N, in the South for P, and in California for both N and P. Then we identified the most suitable conservation strategies using a hierarchy of metrics including nutrient use efficiency (proportion of new nutrient inputs removed by crop harvest), tile drainage, existing buffers for agricultural run-off, and wetland restoration potential. In-field nutrient input reduction emerged as a priority because nutrient use efficiency fell below a high but achievable goal of 0.7 (30% of nutrients applied are not utilized) in 45% and 44% of CONUS subwatersheds for N and P, respectively. In many parts of the southern and western US, in-field conservation (i.e., reducing inputs + preventing nutrients from leaving fields) alone was likely the optimal strategy as agriculture was already well-buffered. However, stacking in-field conservation with additional edge-of-field buffering would be important to conservation strategies in 35% and 29% of CONUS subwatersheds for N and P, respectively. Nutrient use efficiencies were often high enough in the Midwest that proposed strategies focused more on preventing nutrients from leaving fields, managing tile effluent, and buffering agricultural fields. Almost all major river basins would benefit from a variety of nutrient reduction conservation strategies, underscoring the potential of targeted approaches to help limit excess nutrients in surface and ground waters. • Overlaying surplus with conservation opportunities provides novel prioritization. • Nutrient use efficiency can guide conservation strategies. • Reducing in-field N and P inputs was the priority in ∼44% of US subwatersheds. • Stacking in-field and edge-of-field conservation in ∼30–35% of US subwatersheds. [ABSTRACT FROM AUTHOR]