Passive restoration is often quite effective: response to Zahawi et al. (2014)

Although we share many of the ideas expressed by Zahawi et al., we believe that they are more skeptical in some aspects of the value of passive restoration than we are. Their comment is based primarily on experience within tropical habitats with idiosyncratic legal and social circumstances that limit extrapolations to other habitats. Passive restoration is not always slower than active restoration, and restoration goals should not always focus on rapid development of mature vegetation structure and function. Even less mature vegetation may provide important benefits. A meta‐analysis to compare passive and active restoration in a variety of habitats and geographical regions is needed.     

Applied nucleation is a straightforward,cost‐effective forest restoration approach: reply to Ramírez‐Soto et al. (2018)

We agree with Ramírez‐Soto and colleagues that applied nucleation can be an effective approach for tropical forest restoration both in lowland and higher elevation tropical forests. We also contend that it is cheaper than standard plantation‐style plantings and is straightforward to train personnel to implement this approach.     

Overcoming challenges on using native seeds for restoration of megadiverse resource‐poor environments: a reply to Madsen et al.

Madsen et al. (2016) reviewed several major limiting factors to establishment of seedlings in nonforest ecosystems (NFE), and proposed seed enhancement technologies to overcome these restoration barriers. However, biodiverse nutrient‐poor NFE present additional hurdles that preclude landscape‐scale seed‐based restoration and were not mentioned in their review. Here, we discuss issues related to native seed availability and provenance, and shortfalls in knowledge on seed quality testing and dormancy release that severely hamper restoration of degraded nutrient‐impoverished NFE. We present alternatives for overcoming these challenges and highlight the need for investments to find more practical and cost‐effective options for broad‐scale restoration.     

Cost of reproduction in a spring ephemeral species, Adonis ramosa (Ranunculaceae): carbon budget for seed production

BACKGROUND AND AIMS: Spring ephemerals have a specific life-history trait, i.e. shoot growth and sexual reproduction occur simultaneously during a short period from snowmelt to canopy closure in deciduous forests. The aim of this study is to clarify how spring ephemerals invest resources for seed production within a restricted period. METHODS: In order to evaluate the cost of reproduction of a typical spring ephemeral species, Adonis ramosa, an experiment was conducted comprising defoliation treatments (intact, one-third and two-thirds leaf-cutting) and fruit manipulations (control, shading and removal) over two growing seasons. In addition, measurements were made of the movements of carbon assimilated via (13)C tracing. KEY RESULTS: Survival rate was high irrespective of treatments and manipulations. The proportion of flowering plants and plant size decreased as a result of the defoliation treatments over 2 years, but the fruit manipulations did not affect flowering activity or plant size. Seed set and seed number decreased as a result of fruit shading treatment, but the defoliation treatments did not affect current seed production. Individual seed weight also decreased in the second year due to fruit shading. The (13)C tracing experiment revealed that young fruits had photosynthetic ability and current photosynthetic products from leaves were mainly transferred to the below-ground parts, while translocation to fruit was very small even when fruit photosynthesis was restricted by the shading treatment. CONCLUSIONS: Current foliage photosynthetic products are largely stored in the below-ground parts for survival and future growth, and about one-third of the resources for seed production may be attained by fruit photosynthesis. Therefore, the trade-off between current seed production and subsequent growth is weak. The cost of seed production may be buffered by sufficient storage in the below-ground organs, effective photosynthesis under high irradiation and self-assimilation ability of fruits.     

Persistence and recolonisation determine success of bog restoration for aquatic invertebrates: a comment on Mazerolle et al. (2006)

1. Mazerolle et al. (2006) concluded that some aquatic invertebrate species, including bog‐associated species, readily colonise man‐made bog pools. In contrast, in Dutch bog remnants Van Duinen et al. (2003) found that a considerable number of bog‐associated species do not colonise newly created bog pools. 2. The conclusion of Mazerolle et al. (2006) is based on vagile aquatic invertebrates. Here, we question whether their conclusion can be extended to more sedentary species, which were not captured in the Canadian study, but made up an important part of the invertebrate assemblage in the Dutch study. This discrepancy could be caused by sampling artefacts, low colonisation rates of these species or an incomplete restoration of site conditions. 3. In Canada, chances of recolonisation may be higher than in the Netherlands, as natural and near‐natural bogs are more extensive. In the Netherlands, with low chances of recolonisation, persistence of species may be more important. To disentangle the relative importance of persistence and recolonisation, evaluations of the success of restoration projects need to cover the entire invertebrate assemblage, including both vagile and more sedentary species.     

The restoration of Lake Apopka in relation to alternative stable states: an alternative view to that of Bachmann et al. (1999)

Bachmann et al. (1999) postulated that wind energy initiated, and has maintained, high turbidity in hypertrophic (mean chlorophyll a = 92 g l^–1) Lake Apopka, Florida (mean depth = 1.6 m; area = 12500 ha). They asserted that the turbid condition was initiated by a hurricane in late 1947 that destroyed submersed plant beds and that high turbidity has since been maintained by wind-driven resuspension of fluid sediments. In their view, there has been sufficient light for re-establishment of submersed plants over about 38% of the lake bottom, but plant growth has been precluded by the fluid character of the sediments. They concluded that the restoration program of the St. Johns River Water Management District, which includes reduction of the phosphorus (P) loading rate, will not restore water clarity or submersed vegetation. An alternative explanation for Lake Apopka's turbid state is that it was initiated, and has been maintained, by excessive P loading that led to algal blooms and elimination of submersed vegetation through light limitation. The transition to the turbid state was contemporaneous with drainage of 7300 ha of the floodplain wetland to create polders for farming, beginning in the early 1940s. Lake P budgets indicate that drainage of the farms caused a seven-fold increase in the P loading rate (0.08 g TP m^–2 yr^–1 to 0.55 g TP m^–2 yr^–1). Paleolimnological analysis of lake sediments also indicates an increase in the P loading rate in mid-century, concomitant with the decline in submersed vegetation and the increase in phytoplankton abundance. After the increase in P loading, wind disturbance may have accelerated the transition to the turbid state; but, before the increase in P loading, wind disturbance was insufficient to elicit the turbid state, as evidenced by the stability of the clear-water state in the face of 14 hurricanes and 41 tropical storms from 1881 to 1946. Measurements of photosynthetically active radiation (PAR) indicate that light limitation has inhibited submersed plant growth except on the shallowest 5% of the lake bottom. Further, the correlation between the diffuse attentuation coefficient (K _PAR) and chlorophyll a (CHLA) indicates that light limitation would be removed over about 82% of the lake bottom with a reduction in CHLA from 92 g l^–1 to 25 g l^–1. Recently, following a 40% reduction in the P loading rate, the mean total P (TP) concentration, mean CHLA, and total suspended solids fell by about 30% while mean Secchi depth increased by more than 20%. Submersed plant beds appeared in areas devoid of macrophytes for nearly 50 years. These improvements, during a period with no change in mean wind speeds measured at Lake Apopka, provide the strongest evidence that the turbid state has been maintained by excessive P loading and that the current restoration program, which combines P load reduction with planting and removal of planktivorous fish, will be effective.     

Theorizing human impacts into ecological restoration is not a slippery slope,but a toehold for reaching social‐ecological resilience: a counter‐response to McDonald et al. (2019)

In their reply, McDonald et al. have misconstrued several crucial points from our article. In this counter‐response, we clarify our concerns with the Standards as a document with global implications. We highlight our concern with framing preindustrial indigenous peoples' impacts as natural and the colonial connotations of such an assumption. We also discuss practical issues that arise from the Standards' conceptualization of natural variation and suggest avenues for developing frameworks that do not rely on a nature‐culture dichotomy or naturalization of indigenous landscapes.     

Open science and meta‐analysis allow for rapid advances in ecology: A response to Menegotto et al. (2019)

Menegotto and colleagues’ (2019) commentary on our paper (Kinlock et al., 2018) does not negate our findings, but by recategorizing and reanalysing a portion of our data set, advances our knowledge of the latitudinal diversity gradients (LDGs) in marine ecosystems, particularly emphasizing different findings for benthic LDGs as a result of the recategorization of the data. Furthermore, we see the contribution by Menegotto et al. (2019) as highlighting the importance of scientific transparency; we believe that this insight into the nature of LDGs in marine systems would have been delayed, if not unobtainable, had we not provided fully transparent methods and complete data in our paper.     

Artificial Seed Production and Cultivation of the Edible Brown Alga, Sargassum Fulvellum (Turner) C. Agardh: Developing a new Species for Seaweed Cultivation in Korea

Sargassum fulvellum is a brown alga recently introduced to the seaweed cultivation industry in Korea. There is current interest in the commercial scale of aquaculture of this species. For the artificial seeding and cultivation of this alga, growth and maturation were investigated from September 2002 to August 2003. Indoor culture experiments for maturation induction were also conducted at temperatures of 5, 10, 15, 20 and 25 ^∘C and irradiances of 20, 50, 80 and 100 μmol photons m⁻² s⁻¹ under 16:8 h (L:D) photoperiod. Within a given culture test range, higher temperature and irradiance levels favoured the maturation of receptacles in S. fulvellum. Using temperature and irradiance control for thalli, artificial seed production of this species could be done one month earlier than thalli matured in nature. Under natural condition, receptacle formation of the plants began in February, and the eggs were released from March to April. For mature thalli of 200 g wet wt., artificial seeding was complete enough for attachment on seed strings of 100 m. Mean production obtained from the artificial seeding technique in situ was 3.0 kg wet wt m⁻¹ of culture rope during the cultivation period.