Urgent solutions to global climate change are needed. Ambitious tree‐planting initiatives, many already underway, aim to sequester enormous quantities of carbon to partly compensate for anthropogenic ...CO2 emissions, which are a major cause of rising global temperatures. However, tree planting that is poorly planned and executed could actually increase CO2 emissions and have long‐term, deleterious impacts on biodiversity, landscapes and livelihoods. Here, we highlight the main environmental risks of large‐scale tree planting and propose 10 golden rules, based on some of the most recent ecological research, to implement forest ecosystem restoration that maximizes rates of both carbon sequestration and biodiversity recovery while improving livelihoods. These are as follows: (1) Protect existing forest first; (2) Work together (involving all stakeholders); (3) Aim to maximize biodiversity recovery to meet multiple goals; (4) Select appropriate areas for restoration; (5) Use natural regeneration wherever possible; (6) Select species to maximize biodiversity; (7) Use resilient plant material (with appropriate genetic variability and provenance); (8) Plan ahead for infrastructure, capacity and seed supply; (9) Learn by doing (using an adaptive management approach); and (10) Make it pay (ensuring the economic sustainability of the project). We focus on the design of long‐term strategies to tackle the climate and biodiversity crises and support livelihood needs. We emphasize the role of local communities as sources of indigenous knowledge, and the benefits they could derive from successful reforestation that restores ecosystem functioning and delivers a diverse range of forest products and services. While there is no simple and universal recipe for forest restoration, it is crucial to build upon the currently growing public and private interest in this topic, to ensure interventions provide effective, long‐term carbon sinks and maximize benefits for biodiversity and people.
Ten golden rules_graphical Written Summary:We propose ten golden rules for reforestation to optimize carbon sequestration, biodiversity recovery, and livelihood benefits. These are: (1) Protect existing forest first; (2) Work together (involving all stakeholders); (3) Aim to maximize biodiversity recovery to meet multiple goals; (4) Select appropriate areas for restoration; (5) Use natural regeneration wherever possible; (6) Select species to maximize biodiversity; (7) Use resilient plant material (with appropriate genetic variability and provenance); (8) Plan ahead for infrastructure, capacity and seed supply; (9) Learn by doing (using an adaptive management approach); and (10) Make it pay (ensuring the economic sustainability of the project).
Tree-planting is one of the veritable tools for combating urban heat island and improving thermal comfort in the wake of global warming and urbanization. However, trees of different species and ...morphological properties have variable solar attenuation capacity and consequently, thermal comfort regulation potential. Besides, the shadow-cast effect by buildings helps in reducing pedestrian radiant load and consequently improves thermal comfort especially in high-density cities even though ventilation is reduced. Therefore, a holistic and contextual understanding of tree-planting and shadow-casting can help in designing climate-proof cities. In this study, we employed the ENVI-met model to better understand the interaction between these two forms of shading (trees and buildings) on the pedestrians' thermal comfort in Hong Kong and the influence of one over the other. The impact of different urban densities on the thermal comfort improvement potential by eight (8) common tree-species in Hong Kong was specifically studied. Results show that shallow canyons are susceptible to worse thermal condition when compared to their deeper counterparts with similar aspect ratio value. Of all tree configuration parameters, leaf area index, tree height and trunk height are most influential in improving and aggravating daytime and nighttime thermal comfort, respectively. We also found that trees' effectiveness in improving daytime thermal comfort reduces with increasing urban density and vice-versa for nighttime. For the reference of planners and landscape architects, this study recommends tall trees of low canopy density with high trunk in deeper canyons and vice-versa for shallow canyons and open-areas.
•Worsened thermal condition was observed in shallow than deeper canyons of similar aspect ratio value at mid-day.•The impact of shadow and tree shading on daytime and nighttime thermal conditions is determined by different mechanisms.•The efficacy of trees in improving daytime thermal comfort reduces with increasing urban density.•Tall trees of low leaf density and high trunk are proposed for deep canyons and reverse for shallow canyons and open-areas.•Hong Kong's Greening Master Plan can be updated using tree-species selection based on urban density mapping.
Tree planting is not a simple solution Holl, Karen D; Brancalion, Pedro H S
Science (American Association for the Advancement of Science),
2020-May-08, 2020-05-08, 20200508, Volume:
368, Issue:
6491
Journal Article
Peer reviewed
Open access
Tree planting must be carefully planned and implemented to achieve desired outcomes
A plethora of articles suggest that tree planting can overcome a host of environmental problems, including climate ...change, water shortages, and the sixth mass extinction (
1
–
3
). Business leaders and politicians have jumped on the tree-planting bandwagon, and numerous nonprofit organizations and governments worldwide have started initiatives to plant billions or even trillions of trees for a host of social, ecological, and aesthetic reasons. Well-planned tree-planting projects are an important component of global efforts to improve ecological and human well-being. But tree planting becomes problematic when it is promoted as a simple, silver bullet solution and overshadows other actions that have greater potential for addressing the drivers of specific environmental problems, such as taking bold and rapid steps to reduce deforestation and greenhouse gas emissions.
Pro-environmental behaviors (PEBs) may be associated with a personal relationship with nature. We conducted a quasi-experiment with 423 residents who had or had not actively participated in a ...tree-planting scheme and lived in 20 neighborhoods that differ in their greenness level. We tested whether exposure to nature (specified by the amount of vegetation cover in residents’ neighborhoods) and/or past PEB (specified by tree-planting participation) was associated with residents’ PEB and whether key psychological constructs would mediate these relationships. Structural equation mediation models revealed that the level of neighborhood vegetation and involvement in the planting scheme explained 46% of the variance in PEB, with connection to nature, the use of nature for psychological restoration, and environmental attitudes mediating the relationships. Connection to nature was more strongly associated with engagement in PEB than the use of nature for psychological restoration and environmental attitudes.
Increased planting densities have boosted maize yields. Upright plant architecture facilitates dense planting. Here, we cloned
(
) and
, two quantitative trait loci conferring upright plant ...architecture.
is controlled by a two-base sequence polymorphism regulating the expression of a B3-domain transcription factor (
) located 9.5 kilobases downstream.
exhibits differential binding by DRL1 (DROOPING LEAF1), and DRL1 physically interacts with LG1 (LIGULELESS1) and represses LG1 activation of
regulates
(
), which underlies
, altering endogenous brassinosteroid content and leaf angle. The
allele that reduces leaf angle originated from teosinte, the wild ancestor of maize, and has been lost during maize domestication. Introgressing the wild
allele into modern hybrids and editing
enhance high-density maize yields.
Document (table) about planting dates, seeding rates and row spacing for field and forage crops that are sexually propagated. Information for Florida that considers factors as climate and weather ...conditions; fertility, moisture-holding capacity, temperature, and moisture content of the soil; depth to the water table; size and germination of the seed; plant size and growth habit; growing season and water requirements of the crop; and the habits of insects, disease, and other pests.
Summary
High‐density planting is an effective measure for increasing crop yield per unit land area. Leaf angle (LA) is a key trait of plant architecture and a target for genetic improvement of crops. ...Upright leaves allow better light capture in canopy under high‐density planting, thus enhancing photosynthesis efficiency, ventilation and stress resistance, and ultimately higher grain yield. Here, we summarized the latest progress on the cellular and molecular mechanisms regulating LA formation in rice and maize. We suggest several standing out questions for future studies and then propose some promising strategies to manipulate LA for breeding of cereal crops tailored for high‐density planting.
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